ETH Price: $2,534.51 (-1.77%)

Transaction Decoder

Block:
16632251 at Feb-15-2023 06:06:59 AM +UTC
Transaction Fee:
0.005438888578718112 ETH $13.78
Gas Used:
202,484 Gas / 26.860831368 Gwei

Emitted Events:

82 Seaport.OrderFulfilled( orderHash=56BC975C0D28CE4BB9B5A410AB46697AECB01B0C45113AD73F5F165C17A514EB, offerer=0xea5b58dd4b816c127fce00df8351cc8956c207c8, zone=0x0000000000d80cfcb8dfcd8b2c4fd9c813482938, recipient=[Sender] 0x45c9c9eb867fa5cdf0da5de196ee5d0092de7cb6, offer=, consideration= )
83 ERC721DropProxy.0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925( 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925, 0x000000000000000000000000ea5b58dd4b816c127fce00df8351cc8956c207c8, 0x0000000000000000000000000000000000000000000000000000000000000000, 0x0000000000000000000000000000000000000000000000000000000000006f28 )
84 ERC721DropProxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x000000000000000000000000ea5b58dd4b816c127fce00df8351cc8956c207c8, 0x00000000000000000000000045c9c9eb867fa5cdf0da5de196ee5d0092de7cb6, 0x0000000000000000000000000000000000000000000000000000000000006f28 )

Account State Difference:

  Address   Before After State Difference Code
0x00000000...169EdE581
(Seaport 1.1)
0x03C19A84...eb43C8077
(Matchbook: Deployer)
2.850808392105062439 Eth2.850811392105062439 Eth0.000003
0x45C9c9eB...092De7cB6
0.012879938994640129 Eth
Nonce: 192
0.006841050415922017 Eth
Nonce: 193
0.006038888578718112
5.49169526249104514 Eth5.49199898849104514 Eth0.000303726
0xd1466d7A...9fE910611
0xea5B58dd...956C207c8 0.159296907915617566 Eth0.159893907915617566 Eth0.000597

Execution Trace

ETH 0.0006 Seaport.fulfillBasicOrder( parameters=[{name:considerationToken, type:address, order:1, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}, {name:considerationIdentifier, type:uint256, order:2, indexed:false, value:0, valueString:0}, {name:considerationAmount, type:uint256, order:3, indexed:false, value:597000000000000, valueString:597000000000000}, {name:offerer, type:address, order:4, indexed:false, value:0xea5B58dd4b816C127FCE00dF8351cC8956C207c8, valueString:0xea5B58dd4b816C127FCE00dF8351cC8956C207c8}, {name:zone, type:address, order:5, indexed:false, value:0x0000000000D80CfCB8DFCD8B2c4fD9c813482938, valueString:0x0000000000D80CfCB8DFCD8B2c4fD9c813482938}, {name:offerToken, type:address, order:6, indexed:false, value:0xd1466d7A2e13A47677608F68093c5eA9fE910611, valueString:0xd1466d7A2e13A47677608F68093c5eA9fE910611}, {name:offerIdentifier, type:uint256, order:7, indexed:false, value:28456, valueString:28456}, {name:offerAmount, type:uint256, order:8, indexed:false, value:1, valueString:1}, {name:basicOrderType, type:uint8, order:9, indexed:false, value:2, valueString:2}, {name:startTime, type:uint256, order:10, indexed:false, value:1676415873, valueString:1676415873}, {name:endTime, type:uint256, order:11, indexed:false, value:1677020673, valueString:1677020673}, {name:zoneHash, type:bytes32, order:12, indexed:false, value:3100000000000000000000000000000000000000000000000000000000000000, valueString:3100000000000000000000000000000000000000000000000000000000000000}, {name:salt, type:uint256, order:13, indexed:false, value:4155434184400049735, valueString:4155434184400049735}, {name:offererConduitKey, type:bytes32, order:14, indexed:false, value:0000007B02230091A7ED01230072F7006A004D60A8D4E71D599B8104250F0000, valueString:0000007B02230091A7ED01230072F7006A004D60A8D4E71D599B8104250F0000}, {name:fulfillerConduitKey, type:bytes32, order:15, indexed:false, value:0000000000000000000000000000000000000000000000000000000000000000, valueString:0000000000000000000000000000000000000000000000000000000000000000}, {name:totalOriginalAdditionalRecipients, type:uint256, order:16, indexed:false, value:1, valueString:1}, {name:additionalRecipients, type:tuple[], order:17, indexed:false}, {name:signature, type:bytes, order:18, indexed:false, value:0x7D9A1AC18927FCB41F8E5720019CE34605552DAA557AC18C18A3BFD465B22D452CDC41FDEBDBC31CF0813375F6AE1C91B910B34E162D843D1671DC8F3BA97BBD, valueString:0x7D9A1AC18927FCB41F8E5720019CE34605552DAA557AC18C18A3BFD465B22D452CDC41FDEBDBC31CF0813375F6AE1C91B910B34E162D843D1671DC8F3BA97BBD}] ) => ( fulfilled=True )
  • 0x0000000000d80cfcb8dfcd8b2c4fd9c813482938.0e1d31dc( )
  • Null: 0x000...001.43ef8bdc( )
  • Conduit.execute( transfers= ) => ( transfers= )
    • ERC721DropProxy.23b872dd( )
      • ERC721Drop.transferFrom( from=0xea5B58dd4b816C127FCE00dF8351cC8956C207c8, to=0x45C9c9eB867Fa5CdF0DA5dE196Ee5d0092De7cB6, tokenId=28456 )
        • OperatorFilterRegistry.isOperatorAllowed( registrant=0xd1466d7A2e13A47677608F68093c5eA9fE910611, operator=0x1E0049783F008A0085193E00003D00cd54003c71 ) => ( True )
        • ETH 0.000003 Matchbook: Deployer.CALL( )
        • ETH 0.000597 0xea5b58dd4b816c127fce00df8351cc8956c207c8.CALL( )
          fulfillBasicOrder[Consideration (ln:9074)]
          File 1 of 5: Seaport
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { Consideration } from "./lib/Consideration.sol";
          /**
           * @title Seaport
           * @custom:version 1.1
           * @author 0age (0age.eth)
           * @custom:coauthor d1ll0n (d1ll0n.eth)
           * @custom:coauthor transmissions11 (t11s.eth)
           * @custom:contributor Kartik (slokh.eth)
           * @custom:contributor LeFevre (lefevre.eth)
           * @custom:contributor Joseph Schiarizzi (CupOJoseph.eth)
           * @custom:contributor Aspyn Palatnick (stuckinaboot.eth)
           * @custom:contributor James Wenzel (emo.eth)
           * @custom:contributor Stephan Min (stephanm.eth)
           * @custom:contributor Ryan Ghods (ralxz.eth)
           * @custom:contributor hack3r-0m (hack3r-0m.eth)
           * @custom:contributor Diego Estevez (antidiego.eth)
           * @custom:contributor Chomtana (chomtana.eth)
           * @custom:contributor Saw-mon and Natalie (sawmonandnatalie.eth)
           * @custom:contributor 0xBeans (0xBeans.eth)
           * @custom:contributor 0x4non (punkdev.eth)
           * @custom:contributor Laurence E. Day (norsefire.eth)
           * @custom:contributor vectorized.eth (vectorized.eth)
           * @custom:contributor karmacoma (karmacoma.eth)
           * @custom:contributor horsefacts (horsefacts.eth)
           * @custom:contributor UncarvedBlock (uncarvedblock.eth)
           * @custom:contributor Zoraiz Mahmood (zorz.eth)
           * @custom:contributor William Poulin (wpoulin.eth)
           * @custom:contributor Rajiv Patel-O'Connor (rajivpoc.eth)
           * @custom:contributor tserg (tserg.eth)
           * @custom:contributor cygaar (cygaar.eth)
           * @custom:contributor Meta0xNull (meta0xnull.eth)
           * @custom:contributor gpersoon (gpersoon.eth)
           * @custom:contributor Matt Solomon (msolomon.eth)
           * @custom:contributor Weikang Song (weikangs.eth)
           * @custom:contributor zer0dot (zer0dot.eth)
           * @custom:contributor Mudit Gupta (mudit.eth)
           * @custom:contributor leonardoalt (leoalt.eth)
           * @custom:contributor cmichel (cmichel.eth)
           * @custom:contributor PraneshASP (pranesh.eth)
           * @custom:contributor JasperAlexander (jasperalexander.eth)
           * @custom:contributor Ellahi (ellahi.eth)
           * @custom:contributor zaz (1zaz1.eth)
           * @custom:contributor berndartmueller (berndartmueller.eth)
           * @custom:contributor dmfxyz (dmfxyz.eth)
           * @custom:contributor daltoncoder (dontkillrobots.eth)
           * @custom:contributor 0xf4ce (0xf4ce.eth)
           * @custom:contributor phaze (phaze.eth)
           * @custom:contributor hrkrshnn (hrkrshnn.eth)
           * @custom:contributor axic (axic.eth)
           * @custom:contributor leastwood (leastwood.eth)
           * @custom:contributor 0xsanson (sanson.eth)
           * @custom:contributor blockdev (blockd3v.eth)
           * @custom:contributor fiveoutofnine (fiveoutofnine.eth)
           * @custom:contributor shuklaayush (shuklaayush.eth)
           * @custom:contributor 0xPatissier
           * @custom:contributor pcaversaccio
           * @custom:contributor David Eiber
           * @custom:contributor csanuragjain
           * @custom:contributor sach1r0
           * @custom:contributor twojoy0
           * @custom:contributor ori_dabush
           * @custom:contributor Daniel Gelfand
           * @custom:contributor okkothejawa
           * @custom:contributor FlameHorizon
           * @custom:contributor vdrg
           * @custom:contributor dmitriia
           * @custom:contributor bokeh-eth
           * @custom:contributor asutorufos
           * @custom:contributor rfart(rfa)
           * @custom:contributor Riley Holterhus
           * @custom:contributor big-tech-sux
           * @notice Seaport is a generalized ETH/ERC20/ERC721/ERC1155 marketplace. It
           *         minimizes external calls to the greatest extent possible and provides
           *         lightweight methods for common routes as well as more flexible
           *         methods for composing advanced orders or groups of orders. Each order
           *         contains an arbitrary number of items that may be spent (the "offer")
           *         along with an arbitrary number of items that must be received back by
           *         the indicated recipients (the "consideration").
           */
          contract Seaport is Consideration {
              /**
               * @notice Derive and set hashes, reference chainId, and associated domain
               *         separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) Consideration(conduitController) {}
              /**
               * @dev Internal pure function to retrieve and return the name of this
               *      contract.
               *
               * @return The name of this contract.
               */
              function _name() internal pure override returns (string memory) {
                  // Return the name of the contract.
                  assembly {
                      mstore(0x20, 0x20)
                      mstore(0x47, 0x07536561706f7274)
                      return(0x20, 0x60)
                  }
              }
              /**
               * @dev Internal pure function to retrieve the name of this contract as a
               *      string that will be used to derive the name hash in the constructor.
               *
               * @return The name of this contract as a string.
               */
              function _nameString() internal pure override returns (string memory) {
                  // Return the name of the contract.
                  return "Seaport";
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // prettier-ignore
          import {
              BasicOrderParameters,
              OrderComponents,
              Fulfillment,
              FulfillmentComponent,
              Execution,
              Order,
              AdvancedOrder,
              OrderStatus,
              CriteriaResolver
          } from "../lib/ConsiderationStructs.sol";
          /**
           * @title SeaportInterface
           * @author 0age
           * @custom:version 1.1
           * @notice Seaport is a generalized ETH/ERC20/ERC721/ERC1155 marketplace. It
           *         minimizes external calls to the greatest extent possible and provides
           *         lightweight methods for common routes as well as more flexible
           *         methods for composing advanced orders.
           *
           * @dev SeaportInterface contains all external function interfaces for Seaport.
           */
          interface SeaportInterface {
              /**
               * @notice Fulfill an order offering an ERC721 token by supplying Ether (or
               *         the native token for the given chain) as consideration for the
               *         order. An arbitrary number of "additional recipients" may also be
               *         supplied which will each receive native tokens from the fulfiller
               *         as consideration.
               *
               * @param parameters Additional information on the fulfilled order. Note
               *                   that the offerer must first approve this contract (or
               *                   their preferred conduit if indicated by the order) for
               *                   their offered ERC721 token to be transferred.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillBasicOrder(BasicOrderParameters calldata parameters)
                  external
                  payable
                  returns (bool fulfilled);
              /**
               * @notice Fulfill an order with an arbitrary number of items for offer and
               *         consideration. Note that this function does not support
               *         criteria-based orders or partial filling of orders (though
               *         filling the remainder of a partially-filled order is supported).
               *
               * @param order               The order to fulfill. Note that both the
               *                            offerer and the fulfiller must first approve
               *                            this contract (or the corresponding conduit if
               *                            indicated) to transfer any relevant tokens on
               *                            their behalf and that contracts must implement
               *                            `onERC1155Received` to receive ERC1155 tokens
               *                            as consideration.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used, with direct approvals set on
               *                            Seaport.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillOrder(Order calldata order, bytes32 fulfillerConduitKey)
                  external
                  payable
                  returns (bool fulfilled);
              /**
               * @notice Fill an order, fully or partially, with an arbitrary number of
               *         items for offer and consideration alongside criteria resolvers
               *         containing specific token identifiers and associated proofs.
               *
               * @param advancedOrder       The order to fulfill along with the fraction
               *                            of the order to attempt to fill. Note that
               *                            both the offerer and the fulfiller must first
               *                            approve this contract (or their preferred
               *                            conduit if indicated by the order) to transfer
               *                            any relevant tokens on their behalf and that
               *                            contracts must implement `onERC1155Received`
               *                            to receive ERC1155 tokens as consideration.
               *                            Also note that all offer and consideration
               *                            components must have no remainder after
               *                            multiplication of the respective amount with
               *                            the supplied fraction for the partial fill to
               *                            be considered valid.
               * @param criteriaResolvers   An array where each element contains a
               *                            reference to a specific offer or
               *                            consideration, a token identifier, and a proof
               *                            that the supplied token identifier is
               *                            contained in the merkle root held by the item
               *                            in question's criteria element. Note that an
               *                            empty criteria indicates that any
               *                            (transferable) token identifier on the token
               *                            in question is valid and that no associated
               *                            proof needs to be supplied.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used, with direct approvals set on
               *                            Seaport.
               * @param recipient           The intended recipient for all received items,
               *                            with `address(0)` indicating that the caller
               *                            should receive the items.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillAdvancedOrder(
                  AdvancedOrder calldata advancedOrder,
                  CriteriaResolver[] calldata criteriaResolvers,
                  bytes32 fulfillerConduitKey,
                  address recipient
              ) external payable returns (bool fulfilled);
              /**
               * @notice Attempt to fill a group of orders, each with an arbitrary number
               *         of items for offer and consideration. Any order that is not
               *         currently active, has already been fully filled, or has been
               *         cancelled will be omitted. Remaining offer and consideration
               *         items will then be aggregated where possible as indicated by the
               *         supplied offer and consideration component arrays and aggregated
               *         items will be transferred to the fulfiller or to each intended
               *         recipient, respectively. Note that a failing item transfer or an
               *         issue with order formatting will cause the entire batch to fail.
               *         Note that this function does not support criteria-based orders or
               *         partial filling of orders (though filling the remainder of a
               *         partially-filled order is supported).
               *
               * @param orders                    The orders to fulfill. Note that both
               *                                  the offerer and the fulfiller must first
               *                                  approve this contract (or the
               *                                  corresponding conduit if indicated) to
               *                                  transfer any relevant tokens on their
               *                                  behalf and that contracts must implement
               *                                  `onERC1155Received` to receive ERC1155
               *                                  tokens as consideration.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used, with
               *                                  direct approvals set on this contract.
               * @param maximumFulfilled          The maximum number of orders to fulfill.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function fulfillAvailableOrders(
                  Order[] calldata orders,
                  FulfillmentComponent[][] calldata offerFulfillments,
                  FulfillmentComponent[][] calldata considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  uint256 maximumFulfilled
              )
                  external
                  payable
                  returns (bool[] memory availableOrders, Execution[] memory executions);
              /**
               * @notice Attempt to fill a group of orders, fully or partially, with an
               *         arbitrary number of items for offer and consideration per order
               *         alongside criteria resolvers containing specific token
               *         identifiers and associated proofs. Any order that is not
               *         currently active, has already been fully filled, or has been
               *         cancelled will be omitted. Remaining offer and consideration
               *         items will then be aggregated where possible as indicated by the
               *         supplied offer and consideration component arrays and aggregated
               *         items will be transferred to the fulfiller or to each intended
               *         recipient, respectively. Note that a failing item transfer or an
               *         issue with order formatting will cause the entire batch to fail.
               *
               * @param advancedOrders            The orders to fulfill along with the
               *                                  fraction of those orders to attempt to
               *                                  fill. Note that both the offerer and the
               *                                  fulfiller must first approve this
               *                                  contract (or their preferred conduit if
               *                                  indicated by the order) to transfer any
               *                                  relevant tokens on their behalf and that
               *                                  contracts must implement
               *                                  `onERC1155Received` to enable receipt of
               *                                  ERC1155 tokens as consideration. Also
               *                                  note that all offer and consideration
               *                                  components must have no remainder after
               *                                  multiplication of the respective amount
               *                                  with the supplied fraction for an
               *                                  order's partial fill amount to be
               *                                  considered valid.
               * @param criteriaResolvers         An array where each element contains a
               *                                  reference to a specific offer or
               *                                  consideration, a token identifier, and a
               *                                  proof that the supplied token identifier
               *                                  is contained in the merkle root held by
               *                                  the item in question's criteria element.
               *                                  Note that an empty criteria indicates
               *                                  that any (transferable) token
               *                                  identifier on the token in question is
               *                                  valid and that no associated proof needs
               *                                  to be supplied.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used, with
               *                                  direct approvals set on this contract.
               * @param recipient                 The intended recipient for all received
               *                                  items, with `address(0)` indicating that
               *                                  the caller should receive the items.
               * @param maximumFulfilled          The maximum number of orders to fulfill.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function fulfillAvailableAdvancedOrders(
                  AdvancedOrder[] calldata advancedOrders,
                  CriteriaResolver[] calldata criteriaResolvers,
                  FulfillmentComponent[][] calldata offerFulfillments,
                  FulfillmentComponent[][] calldata considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  address recipient,
                  uint256 maximumFulfilled
              )
                  external
                  payable
                  returns (bool[] memory availableOrders, Execution[] memory executions);
              /**
               * @notice Match an arbitrary number of orders, each with an arbitrary
               *         number of items for offer and consideration along with as set of
               *         fulfillments allocating offer components to consideration
               *         components. Note that this function does not support
               *         criteria-based or partial filling of orders (though filling the
               *         remainder of a partially-filled order is supported).
               *
               * @param orders       The orders to match. Note that both the offerer and
               *                     fulfiller on each order must first approve this
               *                     contract (or their conduit if indicated by the order)
               *                     to transfer any relevant tokens on their behalf and
               *                     each consideration recipient must implement
               *                     `onERC1155Received` to enable ERC1155 token receipt.
               * @param fulfillments An array of elements allocating offer components to
               *                     consideration components. Note that each
               *                     consideration component must be fully met for the
               *                     match operation to be valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function matchOrders(
                  Order[] calldata orders,
                  Fulfillment[] calldata fulfillments
              ) external payable returns (Execution[] memory executions);
              /**
               * @notice Match an arbitrary number of full or partial orders, each with an
               *         arbitrary number of items for offer and consideration, supplying
               *         criteria resolvers containing specific token identifiers and
               *         associated proofs as well as fulfillments allocating offer
               *         components to consideration components.
               *
               * @param orders            The advanced orders to match. Note that both the
               *                          offerer and fulfiller on each order must first
               *                          approve this contract (or a preferred conduit if
               *                          indicated by the order) to transfer any relevant
               *                          tokens on their behalf and each consideration
               *                          recipient must implement `onERC1155Received` in
               *                          order to receive ERC1155 tokens. Also note that
               *                          the offer and consideration components for each
               *                          order must have no remainder after multiplying
               *                          the respective amount with the supplied fraction
               *                          in order for the group of partial fills to be
               *                          considered valid.
               * @param criteriaResolvers An array where each element contains a reference
               *                          to a specific order as well as that order's
               *                          offer or consideration, a token identifier, and
               *                          a proof that the supplied token identifier is
               *                          contained in the order's merkle root. Note that
               *                          an empty root indicates that any (transferable)
               *                          token identifier is valid and that no associated
               *                          proof needs to be supplied.
               * @param fulfillments      An array of elements allocating offer components
               *                          to consideration components. Note that each
               *                          consideration component must be fully met in
               *                          order for the match operation to be valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function matchAdvancedOrders(
                  AdvancedOrder[] calldata orders,
                  CriteriaResolver[] calldata criteriaResolvers,
                  Fulfillment[] calldata fulfillments
              ) external payable returns (Execution[] memory executions);
              /**
               * @notice Cancel an arbitrary number of orders. Note that only the offerer
               *         or the zone of a given order may cancel it. Callers should ensure
               *         that the intended order was cancelled by calling `getOrderStatus`
               *         and confirming that `isCancelled` returns `true`.
               *
               * @param orders The orders to cancel.
               *
               * @return cancelled A boolean indicating whether the supplied orders have
               *                   been successfully cancelled.
               */
              function cancel(OrderComponents[] calldata orders)
                  external
                  returns (bool cancelled);
              /**
               * @notice Validate an arbitrary number of orders, thereby registering their
               *         signatures as valid and allowing the fulfiller to skip signature
               *         verification on fulfillment. Note that validated orders may still
               *         be unfulfillable due to invalid item amounts or other factors;
               *         callers should determine whether validated orders are fulfillable
               *         by simulating the fulfillment call prior to execution. Also note
               *         that anyone can validate a signed order, but only the offerer can
               *         validate an order without supplying a signature.
               *
               * @param orders The orders to validate.
               *
               * @return validated A boolean indicating whether the supplied orders have
               *                   been successfully validated.
               */
              function validate(Order[] calldata orders)
                  external
                  returns (bool validated);
              /**
               * @notice Cancel all orders from a given offerer with a given zone in bulk
               *         by incrementing a counter. Note that only the offerer may
               *         increment the counter.
               *
               * @return newCounter The new counter.
               */
              function incrementCounter() external returns (uint256 newCounter);
              /**
               * @notice Retrieve the order hash for a given order.
               *
               * @param order The components of the order.
               *
               * @return orderHash The order hash.
               */
              function getOrderHash(OrderComponents calldata order)
                  external
                  view
                  returns (bytes32 orderHash);
              /**
               * @notice Retrieve the status of a given order by hash, including whether
               *         the order has been cancelled or validated and the fraction of the
               *         order that has been filled.
               *
               * @param orderHash The order hash in question.
               *
               * @return isValidated A boolean indicating whether the order in question
               *                     has been validated (i.e. previously approved or
               *                     partially filled).
               * @return isCancelled A boolean indicating whether the order in question
               *                     has been cancelled.
               * @return totalFilled The total portion of the order that has been filled
               *                     (i.e. the "numerator").
               * @return totalSize   The total size of the order that is either filled or
               *                     unfilled (i.e. the "denominator").
               */
              function getOrderStatus(bytes32 orderHash)
                  external
                  view
                  returns (
                      bool isValidated,
                      bool isCancelled,
                      uint256 totalFilled,
                      uint256 totalSize
                  );
              /**
               * @notice Retrieve the current counter for a given offerer.
               *
               * @param offerer The offerer in question.
               *
               * @return counter The current counter.
               */
              function getCounter(address offerer)
                  external
                  view
                  returns (uint256 counter);
              /**
               * @notice Retrieve configuration information for this contract.
               *
               * @return version           The contract version.
               * @return domainSeparator   The domain separator for this contract.
               * @return conduitController The conduit Controller set for this contract.
               */
              function information()
                  external
                  view
                  returns (
                      string memory version,
                      bytes32 domainSeparator,
                      address conduitController
                  );
              /**
               * @notice Retrieve the name of this contract.
               *
               * @return contractName The name of this contract.
               */
              function name() external view returns (string memory contractName);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import "./TransferHelperStructs.sol";
          import { TokenTransferrer } from "../lib/TokenTransferrer.sol";
          import { ConduitInterface } from "../interfaces/ConduitInterface.sol";
          // prettier-ignore
          import {
              ConduitControllerInterface
          } from "../interfaces/ConduitControllerInterface.sol";
          import { Conduit } from "../conduit/Conduit.sol";
          import { ConduitTransfer } from "../conduit/lib/ConduitStructs.sol";
          // prettier-ignore
          import {
              TransferHelperInterface
          } from "../interfaces/TransferHelperInterface.sol";
          /**
           * @title TransferHelper
           * @author stuckinaboot, stephankmin
           * @notice TransferHelper is a utility contract for transferring
           *         ERC20/ERC721/ERC1155 items in bulk to a specific recipient.
           */
          contract TransferHelper is TransferHelperInterface, TokenTransferrer {
              // Allow for interaction with the conduit controller.
              ConduitControllerInterface internal immutable _CONDUIT_CONTROLLER;
              // Cache the conduit creation hash used by the conduit controller.
              bytes32 internal immutable _CONDUIT_CREATION_CODE_HASH;
              /**
               * @dev Set the supplied conduit controller and retrieve its
               *      conduit creation code hash.
               *
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) {
                  // Get the conduit creation code hash from the supplied conduit
                  // controller and set it as an immutable.
                  ConduitControllerInterface controller = ConduitControllerInterface(
                      conduitController
                  );
                  (_CONDUIT_CREATION_CODE_HASH, ) = controller.getConduitCodeHashes();
                  // Set the supplied conduit controller as an immutable.
                  _CONDUIT_CONTROLLER = controller;
              }
              /**
               * @notice Transfer multiple items to a single recipient.
               *
               * @param items      The items to transfer.
               * @param recipient  The address the items should be transferred to.
               * @param conduitKey The key of the conduit through which the bulk transfer
               *                   should occur.
               *
               * @return magicValue A value indicating that the transfers were successful.
               */
              function bulkTransfer(
                  TransferHelperItem[] calldata items,
                  address recipient,
                  bytes32 conduitKey
              ) external override returns (bytes4 magicValue) {
                  // Retrieve total number of transfers and place on stack.
                  uint256 totalTransfers = items.length;
                  // If no conduitKey is given, use TokenTransferrer to perform transfers.
                  if (conduitKey == bytes32(0)) {
                      // Skip overflow checks: all for loops are indexed starting at zero.
                      unchecked {
                          // Iterate over each transfer.
                          for (uint256 i = 0; i < totalTransfers; ++i) {
                              // Retrieve the transfer in question.
                              TransferHelperItem calldata item = items[i];
                              // Perform a transfer based on the transfer's item type.
                              // Revert if item being transferred is a native token.
                              if (item.itemType == ConduitItemType.NATIVE) {
                                  revert InvalidItemType();
                              } else if (item.itemType == ConduitItemType.ERC20) {
                                  _performERC20Transfer(
                                      item.token,
                                      msg.sender,
                                      recipient,
                                      item.amount
                                  );
                              } else if (item.itemType == ConduitItemType.ERC721) {
                                  _performERC721Transfer(
                                      item.token,
                                      msg.sender,
                                      recipient,
                                      item.identifier
                                  );
                              } else {
                                  _performERC1155Transfer(
                                      item.token,
                                      msg.sender,
                                      recipient,
                                      item.identifier,
                                      item.amount
                                  );
                              }
                          }
                      }
                  }
                  // Otherwise, a conduitKey was provided.
                  else {
                      // Derive the conduit address from the deployer, conduit key
                      // and creation code hash.
                      address conduit = address(
                          uint160(
                              uint256(
                                  keccak256(
                                      abi.encodePacked(
                                          bytes1(0xff),
                                          address(_CONDUIT_CONTROLLER),
                                          conduitKey,
                                          _CONDUIT_CREATION_CODE_HASH
                                      )
                                  )
                              )
                          )
                      );
                      // Declare a new array to populate with each token transfer.
                      ConduitTransfer[] memory conduitTransfers = new ConduitTransfer[](
                          totalTransfers
                      );
                      // Skip overflow checks: all for loops are indexed starting at zero.
                      unchecked {
                          // Iterate over each transfer.
                          for (uint256 i = 0; i < totalTransfers; ++i) {
                              // Retrieve the transfer in question.
                              TransferHelperItem calldata item = items[i];
                              // Create a ConduitTransfer corresponding to each
                              // TransferHelperItem.
                              conduitTransfers[i] = ConduitTransfer(
                                  item.itemType,
                                  item.token,
                                  msg.sender,
                                  recipient,
                                  item.identifier,
                                  item.amount
                              );
                          }
                      }
                      // Call the conduit and execute bulk transfers.
                      ConduitInterface(conduit).execute(conduitTransfers);
                  }
                  // Return a magic value indicating that the transfers were performed.
                  magicValue = this.bulkTransfer.selector;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { ConduitItemType } from "../conduit/lib/ConduitEnums.sol";
          struct TransferHelperItem {
              ConduitItemType itemType;
              address token;
              uint256 identifier;
              uint256 amount;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import "./TokenTransferrerConstants.sol";
          // prettier-ignore
          import {
              TokenTransferrerErrors
          } from "../interfaces/TokenTransferrerErrors.sol";
          import { ConduitBatch1155Transfer } from "../conduit/lib/ConduitStructs.sol";
          /**
           * @title TokenTransferrer
           * @author 0age
           * @custom:coauthor d1ll0n
           * @custom:coauthor transmissions11
           * @notice TokenTransferrer is a library for performing optimized ERC20, ERC721,
           *         ERC1155, and batch ERC1155 transfers, used by both Seaport as well as
           *         by conduits deployed by the ConduitController. Use great caution when
           *         considering these functions for use in other codebases, as there are
           *         significant side effects and edge cases that need to be thoroughly
           *         understood and carefully addressed.
           */
          contract TokenTransferrer is TokenTransferrerErrors {
              /**
               * @dev Internal function to transfer ERC20 tokens from a given originator
               *      to a given recipient. Sufficient approvals must be set on the
               *      contract performing the transfer.
               *
               * @param token      The ERC20 token to transfer.
               * @param from       The originator of the transfer.
               * @param to         The recipient of the transfer.
               * @param amount     The amount to transfer.
               */
              function _performERC20Transfer(
                  address token,
                  address from,
                  address to,
                  uint256 amount
              ) internal {
                  // Utilize assembly to perform an optimized ERC20 token transfer.
                  assembly {
                      // The free memory pointer memory slot will be used when populating
                      // call data for the transfer; read the value and restore it later.
                      let memPointer := mload(FreeMemoryPointerSlot)
                      // Write call data into memory, starting with function selector.
                      mstore(ERC20_transferFrom_sig_ptr, ERC20_transferFrom_signature)
                      mstore(ERC20_transferFrom_from_ptr, from)
                      mstore(ERC20_transferFrom_to_ptr, to)
                      mstore(ERC20_transferFrom_amount_ptr, amount)
                      // Make call & copy up to 32 bytes of return data to scratch space.
                      // Scratch space does not need to be cleared ahead of time, as the
                      // subsequent check will ensure that either at least a full word of
                      // return data is received (in which case it will be overwritten) or
                      // that no data is received (in which case scratch space will be
                      // ignored) on a successful call to the given token.
                      let callStatus := call(
                          gas(),
                          token,
                          0,
                          ERC20_transferFrom_sig_ptr,
                          ERC20_transferFrom_length,
                          0,
                          OneWord
                      )
                      // Determine whether transfer was successful using status & result.
                      let success := and(
                          // Set success to whether the call reverted, if not check it
                          // either returned exactly 1 (can't just be non-zero data), or
                          // had no return data.
                          or(
                              and(eq(mload(0), 1), gt(returndatasize(), 31)),
                              iszero(returndatasize())
                          ),
                          callStatus
                      )
                      // Handle cases where either the transfer failed or no data was
                      // returned. Group these, as most transfers will succeed with data.
                      // Equivalent to `or(iszero(success), iszero(returndatasize()))`
                      // but after it's inverted for JUMPI this expression is cheaper.
                      if iszero(and(success, iszero(iszero(returndatasize())))) {
                          // If the token has no code or the transfer failed: Equivalent
                          // to `or(iszero(success), iszero(extcodesize(token)))` but
                          // after it's inverted for JUMPI this expression is cheaper.
                          if iszero(and(iszero(iszero(extcodesize(token))), success)) {
                              // If the transfer failed:
                              if iszero(success) {
                                  // If it was due to a revert:
                                  if iszero(callStatus) {
                                      // If it returned a message, bubble it up as long as
                                      // sufficient gas remains to do so:
                                      if returndatasize() {
                                          // Ensure that sufficient gas is available to
                                          // copy returndata while expanding memory where
                                          // necessary. Start by computing the word size
                                          // of returndata and allocated memory. Round up
                                          // to the nearest full word.
                                          let returnDataWords := div(
                                              add(returndatasize(), AlmostOneWord),
                                              OneWord
                                          )
                                          // Note: use the free memory pointer in place of
                                          // msize() to work around a Yul warning that
                                          // prevents accessing msize directly when the IR
                                          // pipeline is activated.
                                          let msizeWords := div(memPointer, OneWord)
                                          // Next, compute the cost of the returndatacopy.
                                          let cost := mul(CostPerWord, returnDataWords)
                                          // Then, compute cost of new memory allocation.
                                          if gt(returnDataWords, msizeWords) {
                                              cost := add(
                                                  cost,
                                                  add(
                                                      mul(
                                                          sub(
                                                              returnDataWords,
                                                              msizeWords
                                                          ),
                                                          CostPerWord
                                                      ),
                                                      div(
                                                          sub(
                                                              mul(
                                                                  returnDataWords,
                                                                  returnDataWords
                                                              ),
                                                              mul(msizeWords, msizeWords)
                                                          ),
                                                          MemoryExpansionCoefficient
                                                      )
                                                  )
                                              )
                                          }
                                          // Finally, add a small constant and compare to
                                          // gas remaining; bubble up the revert data if
                                          // enough gas is still available.
                                          if lt(add(cost, ExtraGasBuffer), gas()) {
                                              // Copy returndata to memory; overwrite
                                              // existing memory.
                                              returndatacopy(0, 0, returndatasize())
                                              // Revert, specifying memory region with
                                              // copied returndata.
                                              revert(0, returndatasize())
                                          }
                                      }
                                      // Otherwise revert with a generic error message.
                                      mstore(
                                          TokenTransferGenericFailure_error_sig_ptr,
                                          TokenTransferGenericFailure_error_signature
                                      )
                                      mstore(
                                          TokenTransferGenericFailure_error_token_ptr,
                                          token
                                      )
                                      mstore(
                                          TokenTransferGenericFailure_error_from_ptr,
                                          from
                                      )
                                      mstore(TokenTransferGenericFailure_error_to_ptr, to)
                                      mstore(TokenTransferGenericFailure_error_id_ptr, 0)
                                      mstore(
                                          TokenTransferGenericFailure_error_amount_ptr,
                                          amount
                                      )
                                      revert(
                                          TokenTransferGenericFailure_error_sig_ptr,
                                          TokenTransferGenericFailure_error_length
                                      )
                                  }
                                  // Otherwise revert with a message about the token
                                  // returning false or non-compliant return values.
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_sig_ptr,
                                      BadReturnValueFromERC20OnTransfer_error_signature
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_token_ptr,
                                      token
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_from_ptr,
                                      from
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_to_ptr,
                                      to
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_amount_ptr,
                                      amount
                                  )
                                  revert(
                                      BadReturnValueFromERC20OnTransfer_error_sig_ptr,
                                      BadReturnValueFromERC20OnTransfer_error_length
                                  )
                              }
                              // Otherwise, revert with error about token not having code:
                              mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                              mstore(NoContract_error_token_ptr, token)
                              revert(NoContract_error_sig_ptr, NoContract_error_length)
                          }
                          // Otherwise, the token just returned no data despite the call
                          // having succeeded; no need to optimize for this as it's not
                          // technically ERC20 compliant.
                      }
                      // Restore the original free memory pointer.
                      mstore(FreeMemoryPointerSlot, memPointer)
                      // Restore the zero slot to zero.
                      mstore(ZeroSlot, 0)
                  }
              }
              /**
               * @dev Internal function to transfer an ERC721 token from a given
               *      originator to a given recipient. Sufficient approvals must be set on
               *      the contract performing the transfer. Note that this function does
               *      not check whether the receiver can accept the ERC721 token (i.e. it
               *      does not use `safeTransferFrom`).
               *
               * @param token      The ERC721 token to transfer.
               * @param from       The originator of the transfer.
               * @param to         The recipient of the transfer.
               * @param identifier The tokenId to transfer.
               */
              function _performERC721Transfer(
                  address token,
                  address from,
                  address to,
                  uint256 identifier
              ) internal {
                  // Utilize assembly to perform an optimized ERC721 token transfer.
                  assembly {
                      // If the token has no code, revert.
                      if iszero(extcodesize(token)) {
                          mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                          mstore(NoContract_error_token_ptr, token)
                          revert(NoContract_error_sig_ptr, NoContract_error_length)
                      }
                      // The free memory pointer memory slot will be used when populating
                      // call data for the transfer; read the value and restore it later.
                      let memPointer := mload(FreeMemoryPointerSlot)
                      // Write call data to memory starting with function selector.
                      mstore(ERC721_transferFrom_sig_ptr, ERC721_transferFrom_signature)
                      mstore(ERC721_transferFrom_from_ptr, from)
                      mstore(ERC721_transferFrom_to_ptr, to)
                      mstore(ERC721_transferFrom_id_ptr, identifier)
                      // Perform the call, ignoring return data.
                      let success := call(
                          gas(),
                          token,
                          0,
                          ERC721_transferFrom_sig_ptr,
                          ERC721_transferFrom_length,
                          0,
                          0
                      )
                      // If the transfer reverted:
                      if iszero(success) {
                          // If it returned a message, bubble it up as long as sufficient
                          // gas remains to do so:
                          if returndatasize() {
                              // Ensure that sufficient gas is available to copy
                              // returndata while expanding memory where necessary. Start
                              // by computing word size of returndata & allocated memory.
                              // Round up to the nearest full word.
                              let returnDataWords := div(
                                  add(returndatasize(), AlmostOneWord),
                                  OneWord
                              )
                              // Note: use the free memory pointer in place of msize() to
                              // work around a Yul warning that prevents accessing msize
                              // directly when the IR pipeline is activated.
                              let msizeWords := div(memPointer, OneWord)
                              // Next, compute the cost of the returndatacopy.
                              let cost := mul(CostPerWord, returnDataWords)
                              // Then, compute cost of new memory allocation.
                              if gt(returnDataWords, msizeWords) {
                                  cost := add(
                                      cost,
                                      add(
                                          mul(
                                              sub(returnDataWords, msizeWords),
                                              CostPerWord
                                          ),
                                          div(
                                              sub(
                                                  mul(returnDataWords, returnDataWords),
                                                  mul(msizeWords, msizeWords)
                                              ),
                                              MemoryExpansionCoefficient
                                          )
                                      )
                                  )
                              }
                              // Finally, add a small constant and compare to gas
                              // remaining; bubble up the revert data if enough gas is
                              // still available.
                              if lt(add(cost, ExtraGasBuffer), gas()) {
                                  // Copy returndata to memory; overwrite existing memory.
                                  returndatacopy(0, 0, returndatasize())
                                  // Revert, giving memory region with copied returndata.
                                  revert(0, returndatasize())
                              }
                          }
                          // Otherwise revert with a generic error message.
                          mstore(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_signature
                          )
                          mstore(TokenTransferGenericFailure_error_token_ptr, token)
                          mstore(TokenTransferGenericFailure_error_from_ptr, from)
                          mstore(TokenTransferGenericFailure_error_to_ptr, to)
                          mstore(TokenTransferGenericFailure_error_id_ptr, identifier)
                          mstore(TokenTransferGenericFailure_error_amount_ptr, 1)
                          revert(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_length
                          )
                      }
                      // Restore the original free memory pointer.
                      mstore(FreeMemoryPointerSlot, memPointer)
                      // Restore the zero slot to zero.
                      mstore(ZeroSlot, 0)
                  }
              }
              /**
               * @dev Internal function to transfer ERC1155 tokens from a given
               *      originator to a given recipient. Sufficient approvals must be set on
               *      the contract performing the transfer and contract recipients must
               *      implement the ERC1155TokenReceiver interface to indicate that they
               *      are willing to accept the transfer.
               *
               * @param token      The ERC1155 token to transfer.
               * @param from       The originator of the transfer.
               * @param to         The recipient of the transfer.
               * @param identifier The id to transfer.
               * @param amount     The amount to transfer.
               */
              function _performERC1155Transfer(
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount
              ) internal {
                  // Utilize assembly to perform an optimized ERC1155 token transfer.
                  assembly {
                      // If the token has no code, revert.
                      if iszero(extcodesize(token)) {
                          mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                          mstore(NoContract_error_token_ptr, token)
                          revert(NoContract_error_sig_ptr, NoContract_error_length)
                      }
                      // The following memory slots will be used when populating call data
                      // for the transfer; read the values and restore them later.
                      let memPointer := mload(FreeMemoryPointerSlot)
                      let slot0x80 := mload(Slot0x80)
                      let slot0xA0 := mload(Slot0xA0)
                      let slot0xC0 := mload(Slot0xC0)
                      // Write call data into memory, beginning with function selector.
                      mstore(
                          ERC1155_safeTransferFrom_sig_ptr,
                          ERC1155_safeTransferFrom_signature
                      )
                      mstore(ERC1155_safeTransferFrom_from_ptr, from)
                      mstore(ERC1155_safeTransferFrom_to_ptr, to)
                      mstore(ERC1155_safeTransferFrom_id_ptr, identifier)
                      mstore(ERC1155_safeTransferFrom_amount_ptr, amount)
                      mstore(
                          ERC1155_safeTransferFrom_data_offset_ptr,
                          ERC1155_safeTransferFrom_data_length_offset
                      )
                      mstore(ERC1155_safeTransferFrom_data_length_ptr, 0)
                      // Perform the call, ignoring return data.
                      let success := call(
                          gas(),
                          token,
                          0,
                          ERC1155_safeTransferFrom_sig_ptr,
                          ERC1155_safeTransferFrom_length,
                          0,
                          0
                      )
                      // If the transfer reverted:
                      if iszero(success) {
                          // If it returned a message, bubble it up as long as sufficient
                          // gas remains to do so:
                          if returndatasize() {
                              // Ensure that sufficient gas is available to copy
                              // returndata while expanding memory where necessary. Start
                              // by computing word size of returndata & allocated memory.
                              // Round up to the nearest full word.
                              let returnDataWords := div(
                                  add(returndatasize(), AlmostOneWord),
                                  OneWord
                              )
                              // Note: use the free memory pointer in place of msize() to
                              // work around a Yul warning that prevents accessing msize
                              // directly when the IR pipeline is activated.
                              let msizeWords := div(memPointer, OneWord)
                              // Next, compute the cost of the returndatacopy.
                              let cost := mul(CostPerWord, returnDataWords)
                              // Then, compute cost of new memory allocation.
                              if gt(returnDataWords, msizeWords) {
                                  cost := add(
                                      cost,
                                      add(
                                          mul(
                                              sub(returnDataWords, msizeWords),
                                              CostPerWord
                                          ),
                                          div(
                                              sub(
                                                  mul(returnDataWords, returnDataWords),
                                                  mul(msizeWords, msizeWords)
                                              ),
                                              MemoryExpansionCoefficient
                                          )
                                      )
                                  )
                              }
                              // Finally, add a small constant and compare to gas
                              // remaining; bubble up the revert data if enough gas is
                              // still available.
                              if lt(add(cost, ExtraGasBuffer), gas()) {
                                  // Copy returndata to memory; overwrite existing memory.
                                  returndatacopy(0, 0, returndatasize())
                                  // Revert, giving memory region with copied returndata.
                                  revert(0, returndatasize())
                              }
                          }
                          // Otherwise revert with a generic error message.
                          mstore(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_signature
                          )
                          mstore(TokenTransferGenericFailure_error_token_ptr, token)
                          mstore(TokenTransferGenericFailure_error_from_ptr, from)
                          mstore(TokenTransferGenericFailure_error_to_ptr, to)
                          mstore(TokenTransferGenericFailure_error_id_ptr, identifier)
                          mstore(TokenTransferGenericFailure_error_amount_ptr, amount)
                          revert(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_length
                          )
                      }
                      mstore(Slot0x80, slot0x80) // Restore slot 0x80.
                      mstore(Slot0xA0, slot0xA0) // Restore slot 0xA0.
                      mstore(Slot0xC0, slot0xC0) // Restore slot 0xC0.
                      // Restore the original free memory pointer.
                      mstore(FreeMemoryPointerSlot, memPointer)
                      // Restore the zero slot to zero.
                      mstore(ZeroSlot, 0)
                  }
              }
              /**
               * @dev Internal function to transfer ERC1155 tokens from a given
               *      originator to a given recipient. Sufficient approvals must be set on
               *      the contract performing the transfer and contract recipients must
               *      implement the ERC1155TokenReceiver interface to indicate that they
               *      are willing to accept the transfer. NOTE: this function is not
               *      memory-safe; it will overwrite existing memory, restore the free
               *      memory pointer to the default value, and overwrite the zero slot.
               *      This function should only be called once memory is no longer
               *      required and when uninitialized arrays are not utilized, and memory
               *      should be considered fully corrupted (aside from the existence of a
               *      default-value free memory pointer) after calling this function.
               *
               * @param batchTransfers The group of 1155 batch transfers to perform.
               */
              function _performERC1155BatchTransfers(
                  ConduitBatch1155Transfer[] calldata batchTransfers
              ) internal {
                  // Utilize assembly to perform optimized batch 1155 transfers.
                  assembly {
                      let len := batchTransfers.length
                      // Pointer to first head in the array, which is offset to the struct
                      // at each index. This gets incremented after each loop to avoid
                      // multiplying by 32 to get the offset for each element.
                      let nextElementHeadPtr := batchTransfers.offset
                      // Pointer to beginning of the head of the array. This is the
                      // reference position each offset references. It's held static to
                      // let each loop calculate the data position for an element.
                      let arrayHeadPtr := nextElementHeadPtr
                      // Write the function selector, which will be reused for each call:
                      // safeBatchTransferFrom(address,address,uint256[],uint256[],bytes)
                      mstore(
                          ConduitBatch1155Transfer_from_offset,
                          ERC1155_safeBatchTransferFrom_signature
                      )
                      // Iterate over each batch transfer.
                      for {
                          let i := 0
                      } lt(i, len) {
                          i := add(i, 1)
                      } {
                          // Read the offset to the beginning of the element and add
                          // it to pointer to the beginning of the array head to get
                          // the absolute position of the element in calldata.
                          let elementPtr := add(
                              arrayHeadPtr,
                              calldataload(nextElementHeadPtr)
                          )
                          // Retrieve the token from calldata.
                          let token := calldataload(elementPtr)
                          // If the token has no code, revert.
                          if iszero(extcodesize(token)) {
                              mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                              mstore(NoContract_error_token_ptr, token)
                              revert(NoContract_error_sig_ptr, NoContract_error_length)
                          }
                          // Get the total number of supplied ids.
                          let idsLength := calldataload(
                              add(elementPtr, ConduitBatch1155Transfer_ids_length_offset)
                          )
                          // Determine the expected offset for the amounts array.
                          let expectedAmountsOffset := add(
                              ConduitBatch1155Transfer_amounts_length_baseOffset,
                              mul(idsLength, OneWord)
                          )
                          // Validate struct encoding.
                          let invalidEncoding := iszero(
                              and(
                                  // ids.length == amounts.length
                                  eq(
                                      idsLength,
                                      calldataload(add(elementPtr, expectedAmountsOffset))
                                  ),
                                  and(
                                      // ids_offset == 0xa0
                                      eq(
                                          calldataload(
                                              add(
                                                  elementPtr,
                                                  ConduitBatch1155Transfer_ids_head_offset
                                              )
                                          ),
                                          ConduitBatch1155Transfer_ids_length_offset
                                      ),
                                      // amounts_offset == 0xc0 + ids.length*32
                                      eq(
                                          calldataload(
                                              add(
                                                  elementPtr,
                                                  ConduitBatchTransfer_amounts_head_offset
                                              )
                                          ),
                                          expectedAmountsOffset
                                      )
                                  )
                              )
                          )
                          // Revert with an error if the encoding is not valid.
                          if invalidEncoding {
                              mstore(
                                  Invalid1155BatchTransferEncoding_ptr,
                                  Invalid1155BatchTransferEncoding_selector
                              )
                              revert(
                                  Invalid1155BatchTransferEncoding_ptr,
                                  Invalid1155BatchTransferEncoding_length
                              )
                          }
                          // Update the offset position for the next loop
                          nextElementHeadPtr := add(nextElementHeadPtr, OneWord)
                          // Copy the first section of calldata (before dynamic values).
                          calldatacopy(
                              BatchTransfer1155Params_ptr,
                              add(elementPtr, ConduitBatch1155Transfer_from_offset),
                              ConduitBatch1155Transfer_usable_head_size
                          )
                          // Determine size of calldata required for ids and amounts. Note
                          // that the size includes both lengths as well as the data.
                          let idsAndAmountsSize := add(TwoWords, mul(idsLength, TwoWords))
                          // Update the offset for the data array in memory.
                          mstore(
                              BatchTransfer1155Params_data_head_ptr,
                              add(
                                  BatchTransfer1155Params_ids_length_offset,
                                  idsAndAmountsSize
                              )
                          )
                          // Set the length of the data array in memory to zero.
                          mstore(
                              add(
                                  BatchTransfer1155Params_data_length_basePtr,
                                  idsAndAmountsSize
                              ),
                              0
                          )
                          // Determine the total calldata size for the call to transfer.
                          let transferDataSize := add(
                              BatchTransfer1155Params_calldata_baseSize,
                              idsAndAmountsSize
                          )
                          // Copy second section of calldata (including dynamic values).
                          calldatacopy(
                              BatchTransfer1155Params_ids_length_ptr,
                              add(elementPtr, ConduitBatch1155Transfer_ids_length_offset),
                              idsAndAmountsSize
                          )
                          // Perform the call to transfer 1155 tokens.
                          let success := call(
                              gas(),
                              token,
                              0,
                              ConduitBatch1155Transfer_from_offset, // Data portion start.
                              transferDataSize, // Location of the length of callData.
                              0,
                              0
                          )
                          // If the transfer reverted:
                          if iszero(success) {
                              // If it returned a message, bubble it up as long as
                              // sufficient gas remains to do so:
                              if returndatasize() {
                                  // Ensure that sufficient gas is available to copy
                                  // returndata while expanding memory where necessary.
                                  // Start by computing word size of returndata and
                                  // allocated memory. Round up to the nearest full word.
                                  let returnDataWords := div(
                                      add(returndatasize(), AlmostOneWord),
                                      OneWord
                                  )
                                  // Note: use transferDataSize in place of msize() to
                                  // work around a Yul warning that prevents accessing
                                  // msize directly when the IR pipeline is activated.
                                  // The free memory pointer is not used here because
                                  // this function does almost all memory management
                                  // manually and does not update it, and transferDataSize
                                  // should be the largest memory value used (unless a
                                  // previous batch was larger).
                                  let msizeWords := div(transferDataSize, OneWord)
                                  // Next, compute the cost of the returndatacopy.
                                  let cost := mul(CostPerWord, returnDataWords)
                                  // Then, compute cost of new memory allocation.
                                  if gt(returnDataWords, msizeWords) {
                                      cost := add(
                                          cost,
                                          add(
                                              mul(
                                                  sub(returnDataWords, msizeWords),
                                                  CostPerWord
                                              ),
                                              div(
                                                  sub(
                                                      mul(
                                                          returnDataWords,
                                                          returnDataWords
                                                      ),
                                                      mul(msizeWords, msizeWords)
                                                  ),
                                                  MemoryExpansionCoefficient
                                              )
                                          )
                                      )
                                  }
                                  // Finally, add a small constant and compare to gas
                                  // remaining; bubble up the revert data if enough gas is
                                  // still available.
                                  if lt(add(cost, ExtraGasBuffer), gas()) {
                                      // Copy returndata to memory; overwrite existing.
                                      returndatacopy(0, 0, returndatasize())
                                      // Revert with memory region containing returndata.
                                      revert(0, returndatasize())
                                  }
                              }
                              // Set the error signature.
                              mstore(
                                  0,
                                  ERC1155BatchTransferGenericFailure_error_signature
                              )
                              // Write the token.
                              mstore(ERC1155BatchTransferGenericFailure_token_ptr, token)
                              // Increase the offset to ids by 32.
                              mstore(
                                  BatchTransfer1155Params_ids_head_ptr,
                                  ERC1155BatchTransferGenericFailure_ids_offset
                              )
                              // Increase the offset to amounts by 32.
                              mstore(
                                  BatchTransfer1155Params_amounts_head_ptr,
                                  add(
                                      OneWord,
                                      mload(BatchTransfer1155Params_amounts_head_ptr)
                                  )
                              )
                              // Return modified region. The total size stays the same as
                              // `token` uses the same number of bytes as `data.length`.
                              revert(0, transferDataSize)
                          }
                      }
                      // Reset the free memory pointer to the default value; memory must
                      // be assumed to be dirtied and not reused from this point forward.
                      // Also note that the zero slot is not reset to zero, meaning empty
                      // arrays cannot be safely created or utilized until it is restored.
                      mstore(FreeMemoryPointerSlot, DefaultFreeMemoryPointer)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // prettier-ignore
          import {
              ConduitTransfer,
              ConduitBatch1155Transfer
          } from "../conduit/lib/ConduitStructs.sol";
          /**
           * @title ConduitInterface
           * @author 0age
           * @notice ConduitInterface contains all external function interfaces, events,
           *         and errors for conduit contracts.
           */
          interface ConduitInterface {
              /**
               * @dev Revert with an error when attempting to execute transfers using a
               *      caller that does not have an open channel.
               */
              error ChannelClosed(address channel);
              /**
               * @dev Revert with an error when attempting to update a channel to the
               *      current status of that channel.
               */
              error ChannelStatusAlreadySet(address channel, bool isOpen);
              /**
               * @dev Revert with an error when attempting to execute a transfer for an
               *      item that does not have an ERC20/721/1155 item type.
               */
              error InvalidItemType();
              /**
               * @dev Revert with an error when attempting to update the status of a
               *      channel from a caller that is not the conduit controller.
               */
              error InvalidController();
              /**
               * @dev Emit an event whenever a channel is opened or closed.
               *
               * @param channel The channel that has been updated.
               * @param open    A boolean indicating whether the conduit is open or not.
               */
              event ChannelUpdated(address indexed channel, bool open);
              /**
               * @notice Execute a sequence of ERC20/721/1155 transfers. Only a caller
               *         with an open channel can call this function.
               *
               * @param transfers The ERC20/721/1155 transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function execute(ConduitTransfer[] calldata transfers)
                  external
                  returns (bytes4 magicValue);
              /**
               * @notice Execute a sequence of batch 1155 transfers. Only a caller with an
               *         open channel can call this function.
               *
               * @param batch1155Transfers The 1155 batch transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function executeBatch1155(
                  ConduitBatch1155Transfer[] calldata batch1155Transfers
              ) external returns (bytes4 magicValue);
              /**
               * @notice Execute a sequence of transfers, both single and batch 1155. Only
               *         a caller with an open channel can call this function.
               *
               * @param standardTransfers  The ERC20/721/1155 transfers to perform.
               * @param batch1155Transfers The 1155 batch transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function executeWithBatch1155(
                  ConduitTransfer[] calldata standardTransfers,
                  ConduitBatch1155Transfer[] calldata batch1155Transfers
              ) external returns (bytes4 magicValue);
              /**
               * @notice Open or close a given channel. Only callable by the controller.
               *
               * @param channel The channel to open or close.
               * @param isOpen  The status of the channel (either open or closed).
               */
              function updateChannel(address channel, bool isOpen) external;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title ConduitControllerInterface
           * @author 0age
           * @notice ConduitControllerInterface contains all external function interfaces,
           *         structs, events, and errors for the conduit controller.
           */
          interface ConduitControllerInterface {
              /**
               * @dev Track the conduit key, current owner, new potential owner, and open
               *      channels for each deployed conduit.
               */
              struct ConduitProperties {
                  bytes32 key;
                  address owner;
                  address potentialOwner;
                  address[] channels;
                  mapping(address => uint256) channelIndexesPlusOne;
              }
              /**
               * @dev Emit an event whenever a new conduit is created.
               *
               * @param conduit    The newly created conduit.
               * @param conduitKey The conduit key used to create the new conduit.
               */
              event NewConduit(address conduit, bytes32 conduitKey);
              /**
               * @dev Emit an event whenever conduit ownership is transferred.
               *
               * @param conduit       The conduit for which ownership has been
               *                      transferred.
               * @param previousOwner The previous owner of the conduit.
               * @param newOwner      The new owner of the conduit.
               */
              event OwnershipTransferred(
                  address indexed conduit,
                  address indexed previousOwner,
                  address indexed newOwner
              );
              /**
               * @dev Emit an event whenever a conduit owner registers a new potential
               *      owner for that conduit.
               *
               * @param newPotentialOwner The new potential owner of the conduit.
               */
              event PotentialOwnerUpdated(address indexed newPotentialOwner);
              /**
               * @dev Revert with an error when attempting to create a new conduit using a
               *      conduit key where the first twenty bytes of the key do not match the
               *      address of the caller.
               */
              error InvalidCreator();
              /**
               * @dev Revert with an error when attempting to create a new conduit when no
               *      initial owner address is supplied.
               */
              error InvalidInitialOwner();
              /**
               * @dev Revert with an error when attempting to set a new potential owner
               *      that is already set.
               */
              error NewPotentialOwnerAlreadySet(
                  address conduit,
                  address newPotentialOwner
              );
              /**
               * @dev Revert with an error when attempting to cancel ownership transfer
               *      when no new potential owner is currently set.
               */
              error NoPotentialOwnerCurrentlySet(address conduit);
              /**
               * @dev Revert with an error when attempting to interact with a conduit that
               *      does not yet exist.
               */
              error NoConduit();
              /**
               * @dev Revert with an error when attempting to create a conduit that
               *      already exists.
               */
              error ConduitAlreadyExists(address conduit);
              /**
               * @dev Revert with an error when attempting to update channels or transfer
               *      ownership of a conduit when the caller is not the owner of the
               *      conduit in question.
               */
              error CallerIsNotOwner(address conduit);
              /**
               * @dev Revert with an error when attempting to register a new potential
               *      owner and supplying the null address.
               */
              error NewPotentialOwnerIsZeroAddress(address conduit);
              /**
               * @dev Revert with an error when attempting to claim ownership of a conduit
               *      with a caller that is not the current potential owner for the
               *      conduit in question.
               */
              error CallerIsNotNewPotentialOwner(address conduit);
              /**
               * @dev Revert with an error when attempting to retrieve a channel using an
               *      index that is out of range.
               */
              error ChannelOutOfRange(address conduit);
              /**
               * @notice Deploy a new conduit using a supplied conduit key and assigning
               *         an initial owner for the deployed conduit. Note that the first
               *         twenty bytes of the supplied conduit key must match the caller
               *         and that a new conduit cannot be created if one has already been
               *         deployed using the same conduit key.
               *
               * @param conduitKey   The conduit key used to deploy the conduit. Note that
               *                     the first twenty bytes of the conduit key must match
               *                     the caller of this contract.
               * @param initialOwner The initial owner to set for the new conduit.
               *
               * @return conduit The address of the newly deployed conduit.
               */
              function createConduit(bytes32 conduitKey, address initialOwner)
                  external
                  returns (address conduit);
              /**
               * @notice Open or close a channel on a given conduit, thereby allowing the
               *         specified account to execute transfers against that conduit.
               *         Extreme care must be taken when updating channels, as malicious
               *         or vulnerable channels can transfer any ERC20, ERC721 and ERC1155
               *         tokens where the token holder has granted the conduit approval.
               *         Only the owner of the conduit in question may call this function.
               *
               * @param conduit The conduit for which to open or close the channel.
               * @param channel The channel to open or close on the conduit.
               * @param isOpen  A boolean indicating whether to open or close the channel.
               */
              function updateChannel(
                  address conduit,
                  address channel,
                  bool isOpen
              ) external;
              /**
               * @notice Initiate conduit ownership transfer by assigning a new potential
               *         owner for the given conduit. Once set, the new potential owner
               *         may call `acceptOwnership` to claim ownership of the conduit.
               *         Only the owner of the conduit in question may call this function.
               *
               * @param conduit The conduit for which to initiate ownership transfer.
               * @param newPotentialOwner The new potential owner of the conduit.
               */
              function transferOwnership(address conduit, address newPotentialOwner)
                  external;
              /**
               * @notice Clear the currently set potential owner, if any, from a conduit.
               *         Only the owner of the conduit in question may call this function.
               *
               * @param conduit The conduit for which to cancel ownership transfer.
               */
              function cancelOwnershipTransfer(address conduit) external;
              /**
               * @notice Accept ownership of a supplied conduit. Only accounts that the
               *         current owner has set as the new potential owner may call this
               *         function.
               *
               * @param conduit The conduit for which to accept ownership.
               */
              function acceptOwnership(address conduit) external;
              /**
               * @notice Retrieve the current owner of a deployed conduit.
               *
               * @param conduit The conduit for which to retrieve the associated owner.
               *
               * @return owner The owner of the supplied conduit.
               */
              function ownerOf(address conduit) external view returns (address owner);
              /**
               * @notice Retrieve the conduit key for a deployed conduit via reverse
               *         lookup.
               *
               * @param conduit The conduit for which to retrieve the associated conduit
               *                key.
               *
               * @return conduitKey The conduit key used to deploy the supplied conduit.
               */
              function getKey(address conduit) external view returns (bytes32 conduitKey);
              /**
               * @notice Derive the conduit associated with a given conduit key and
               *         determine whether that conduit exists (i.e. whether it has been
               *         deployed).
               *
               * @param conduitKey The conduit key used to derive the conduit.
               *
               * @return conduit The derived address of the conduit.
               * @return exists  A boolean indicating whether the derived conduit has been
               *                 deployed or not.
               */
              function getConduit(bytes32 conduitKey)
                  external
                  view
                  returns (address conduit, bool exists);
              /**
               * @notice Retrieve the potential owner, if any, for a given conduit. The
               *         current owner may set a new potential owner via
               *         `transferOwnership` and that owner may then accept ownership of
               *         the conduit in question via `acceptOwnership`.
               *
               * @param conduit The conduit for which to retrieve the potential owner.
               *
               * @return potentialOwner The potential owner, if any, for the conduit.
               */
              function getPotentialOwner(address conduit)
                  external
                  view
                  returns (address potentialOwner);
              /**
               * @notice Retrieve the status (either open or closed) of a given channel on
               *         a conduit.
               *
               * @param conduit The conduit for which to retrieve the channel status.
               * @param channel The channel for which to retrieve the status.
               *
               * @return isOpen The status of the channel on the given conduit.
               */
              function getChannelStatus(address conduit, address channel)
                  external
                  view
                  returns (bool isOpen);
              /**
               * @notice Retrieve the total number of open channels for a given conduit.
               *
               * @param conduit The conduit for which to retrieve the total channel count.
               *
               * @return totalChannels The total number of open channels for the conduit.
               */
              function getTotalChannels(address conduit)
                  external
                  view
                  returns (uint256 totalChannels);
              /**
               * @notice Retrieve an open channel at a specific index for a given conduit.
               *         Note that the index of a channel can change as a result of other
               *         channels being closed on the conduit.
               *
               * @param conduit      The conduit for which to retrieve the open channel.
               * @param channelIndex The index of the channel in question.
               *
               * @return channel The open channel, if any, at the specified channel index.
               */
              function getChannel(address conduit, uint256 channelIndex)
                  external
                  view
                  returns (address channel);
              /**
               * @notice Retrieve all open channels for a given conduit. Note that calling
               *         this function for a conduit with many channels will revert with
               *         an out-of-gas error.
               *
               * @param conduit The conduit for which to retrieve open channels.
               *
               * @return channels An array of open channels on the given conduit.
               */
              function getChannels(address conduit)
                  external
                  view
                  returns (address[] memory channels);
              /**
               * @dev Retrieve the conduit creation code and runtime code hashes.
               */
              function getConduitCodeHashes()
                  external
                  view
                  returns (bytes32 creationCodeHash, bytes32 runtimeCodeHash);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { ConduitInterface } from "../interfaces/ConduitInterface.sol";
          import { ConduitItemType } from "./lib/ConduitEnums.sol";
          import { TokenTransferrer } from "../lib/TokenTransferrer.sol";
          // prettier-ignore
          import {
              ConduitTransfer,
              ConduitBatch1155Transfer
          } from "./lib/ConduitStructs.sol";
          import "./lib/ConduitConstants.sol";
          /**
           * @title Conduit
           * @author 0age
           * @notice This contract serves as an originator for "proxied" transfers. Each
           *         conduit is deployed and controlled by a "conduit controller" that can
           *         add and remove "channels" or contracts that can instruct the conduit
           *         to transfer approved ERC20/721/1155 tokens. *IMPORTANT NOTE: each
           *         conduit has an owner that can arbitrarily add or remove channels, and
           *         a malicious or negligent owner can add a channel that allows for any
           *         approved ERC20/721/1155 tokens to be taken immediately — be extremely
           *         cautious with what conduits you give token approvals to!*
           */
          contract Conduit is ConduitInterface, TokenTransferrer {
              // Set deployer as an immutable controller that can update channel statuses.
              address private immutable _controller;
              // Track the status of each channel.
              mapping(address => bool) private _channels;
              /**
               * @notice Ensure that the caller is currently registered as an open channel
               *         on the conduit.
               */
              modifier onlyOpenChannel() {
                  // Utilize assembly to access channel storage mapping directly.
                  assembly {
                      // Write the caller to scratch space.
                      mstore(ChannelKey_channel_ptr, caller())
                      // Write the storage slot for _channels to scratch space.
                      mstore(ChannelKey_slot_ptr, _channels.slot)
                      // Derive the position in storage of _channels[msg.sender]
                      // and check if the stored value is zero.
                      if iszero(
                          sload(keccak256(ChannelKey_channel_ptr, ChannelKey_length))
                      ) {
                          // The caller is not an open channel; revert with
                          // ChannelClosed(caller). First, set error signature in memory.
                          mstore(ChannelClosed_error_ptr, ChannelClosed_error_signature)
                          // Next, set the caller as the argument.
                          mstore(ChannelClosed_channel_ptr, caller())
                          // Finally, revert, returning full custom error with argument.
                          revert(ChannelClosed_error_ptr, ChannelClosed_error_length)
                      }
                  }
                  // Continue with function execution.
                  _;
              }
              /**
               * @notice In the constructor, set the deployer as the controller.
               */
              constructor() {
                  // Set the deployer as the controller.
                  _controller = msg.sender;
              }
              /**
               * @notice Execute a sequence of ERC20/721/1155 transfers. Only a caller
               *         with an open channel can call this function. Note that channels
               *         are expected to implement reentrancy protection if desired, and
               *         that cross-channel reentrancy may be possible if the conduit has
               *         multiple open channels at once. Also note that channels are
               *         expected to implement checks against transferring any zero-amount
               *         items if that constraint is desired.
               *
               * @param transfers The ERC20/721/1155 transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function execute(ConduitTransfer[] calldata transfers)
                  external
                  override
                  onlyOpenChannel
                  returns (bytes4 magicValue)
              {
                  // Retrieve the total number of transfers and place on the stack.
                  uint256 totalStandardTransfers = transfers.length;
                  // Iterate over each transfer.
                  for (uint256 i = 0; i < totalStandardTransfers; ) {
                      // Retrieve the transfer in question and perform the transfer.
                      _transfer(transfers[i]);
                      // Skip overflow check as for loop is indexed starting at zero.
                      unchecked {
                          ++i;
                      }
                  }
                  // Return a magic value indicating that the transfers were performed.
                  magicValue = this.execute.selector;
              }
              /**
               * @notice Execute a sequence of batch 1155 item transfers. Only a caller
               *         with an open channel can call this function. Note that channels
               *         are expected to implement reentrancy protection if desired, and
               *         that cross-channel reentrancy may be possible if the conduit has
               *         multiple open channels at once. Also note that channels are
               *         expected to implement checks against transferring any zero-amount
               *         items if that constraint is desired.
               *
               * @param batchTransfers The 1155 batch item transfers to perform.
               *
               * @return magicValue A magic value indicating that the item transfers were
               *                    performed successfully.
               */
              function executeBatch1155(
                  ConduitBatch1155Transfer[] calldata batchTransfers
              ) external override onlyOpenChannel returns (bytes4 magicValue) {
                  // Perform 1155 batch transfers. Note that memory should be considered
                  // entirely corrupted from this point forward.
                  _performERC1155BatchTransfers(batchTransfers);
                  // Return a magic value indicating that the transfers were performed.
                  magicValue = this.executeBatch1155.selector;
              }
              /**
               * @notice Execute a sequence of transfers, both single ERC20/721/1155 item
               *         transfers as well as batch 1155 item transfers. Only a caller
               *         with an open channel can call this function. Note that channels
               *         are expected to implement reentrancy protection if desired, and
               *         that cross-channel reentrancy may be possible if the conduit has
               *         multiple open channels at once. Also note that channels are
               *         expected to implement checks against transferring any zero-amount
               *         items if that constraint is desired.
               *
               * @param standardTransfers The ERC20/721/1155 item transfers to perform.
               * @param batchTransfers    The 1155 batch item transfers to perform.
               *
               * @return magicValue A magic value indicating that the item transfers were
               *                    performed successfully.
               */
              function executeWithBatch1155(
                  ConduitTransfer[] calldata standardTransfers,
                  ConduitBatch1155Transfer[] calldata batchTransfers
              ) external override onlyOpenChannel returns (bytes4 magicValue) {
                  // Retrieve the total number of transfers and place on the stack.
                  uint256 totalStandardTransfers = standardTransfers.length;
                  // Iterate over each standard transfer.
                  for (uint256 i = 0; i < totalStandardTransfers; ) {
                      // Retrieve the transfer in question and perform the transfer.
                      _transfer(standardTransfers[i]);
                      // Skip overflow check as for loop is indexed starting at zero.
                      unchecked {
                          ++i;
                      }
                  }
                  // Perform 1155 batch transfers. Note that memory should be considered
                  // entirely corrupted from this point forward aside from the free memory
                  // pointer having the default value.
                  _performERC1155BatchTransfers(batchTransfers);
                  // Return a magic value indicating that the transfers were performed.
                  magicValue = this.executeWithBatch1155.selector;
              }
              /**
               * @notice Open or close a given channel. Only callable by the controller.
               *
               * @param channel The channel to open or close.
               * @param isOpen  The status of the channel (either open or closed).
               */
              function updateChannel(address channel, bool isOpen) external override {
                  // Ensure that the caller is the controller of this contract.
                  if (msg.sender != _controller) {
                      revert InvalidController();
                  }
                  // Ensure that the channel does not already have the indicated status.
                  if (_channels[channel] == isOpen) {
                      revert ChannelStatusAlreadySet(channel, isOpen);
                  }
                  // Update the status of the channel.
                  _channels[channel] = isOpen;
                  // Emit a corresponding event.
                  emit ChannelUpdated(channel, isOpen);
              }
              /**
               * @dev Internal function to transfer a given ERC20/721/1155 item. Note that
               *      channels are expected to implement checks against transferring any
               *      zero-amount items if that constraint is desired.
               *
               * @param item The ERC20/721/1155 item to transfer.
               */
              function _transfer(ConduitTransfer calldata item) internal {
                  // Determine the transfer method based on the respective item type.
                  if (item.itemType == ConduitItemType.ERC20) {
                      // Transfer ERC20 token. Note that item.identifier is ignored and
                      // therefore ERC20 transfer items are potentially malleable — this
                      // check should be performed by the calling channel if a constraint
                      // on item malleability is desired.
                      _performERC20Transfer(item.token, item.from, item.to, item.amount);
                  } else if (item.itemType == ConduitItemType.ERC721) {
                      // Ensure that exactly one 721 item is being transferred.
                      if (item.amount != 1) {
                          revert InvalidERC721TransferAmount();
                      }
                      // Transfer ERC721 token.
                      _performERC721Transfer(
                          item.token,
                          item.from,
                          item.to,
                          item.identifier
                      );
                  } else if (item.itemType == ConduitItemType.ERC1155) {
                      // Transfer ERC1155 token.
                      _performERC1155Transfer(
                          item.token,
                          item.from,
                          item.to,
                          item.identifier,
                          item.amount
                      );
                  } else {
                      // Throw with an error.
                      revert InvalidItemType();
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { ConduitItemType } from "./ConduitEnums.sol";
          struct ConduitTransfer {
              ConduitItemType itemType;
              address token;
              address from;
              address to;
              uint256 identifier;
              uint256 amount;
          }
          struct ConduitBatch1155Transfer {
              address token;
              address from;
              address to;
              uint256[] ids;
              uint256[] amounts;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { TransferHelperItem } from "../helpers/TransferHelperStructs.sol";
          interface TransferHelperInterface {
              /**
               * @dev Revert with an error when attempting to execute transfers with a
               *      NATIVE itemType.
               */
              error InvalidItemType();
              /**
               * @notice Transfer multiple items to a single recipient.
               *
               * @param items The items to transfer.
               * @param recipient  The address the items should be transferred to.
               * @param conduitKey  The key of the conduit performing the bulk transfer.
               */
              function bulkTransfer(
                  TransferHelperItem[] calldata items,
                  address recipient,
                  bytes32 conduitKey
              ) external returns (bytes4);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          enum ConduitItemType {
              NATIVE, // unused
              ERC20,
              ERC721,
              ERC1155
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /*
           * -------------------------- Disambiguation & Other Notes ---------------------
           *    - The term "head" is used as it is in the documentation for ABI encoding,
           *      but only in reference to dynamic types, i.e. it always refers to the
           *      offset or pointer to the body of a dynamic type. In calldata, the head
           *      is always an offset (relative to the parent object), while in memory,
           *      the head is always the pointer to the body. More information found here:
           *      https://docs.soliditylang.org/en/v0.8.14/abi-spec.html#argument-encoding
           *        - Note that the length of an array is separate from and precedes the
           *          head of the array.
           *
           *    - The term "body" is used in place of the term "head" used in the ABI
           *      documentation. It refers to the start of the data for a dynamic type,
           *      e.g. the first word of a struct or the first word of the first element
           *      in an array.
           *
           *    - The term "pointer" is used to describe the absolute position of a value
           *      and never an offset relative to another value.
           *        - The suffix "_ptr" refers to a memory pointer.
           *        - The suffix "_cdPtr" refers to a calldata pointer.
           *
           *    - The term "offset" is used to describe the position of a value relative
           *      to some parent value. For example, OrderParameters_conduit_offset is the
           *      offset to the "conduit" value in the OrderParameters struct relative to
           *      the start of the body.
           *        - Note: Offsets are used to derive pointers.
           *
           *    - Some structs have pointers defined for all of their fields in this file.
           *      Lines which are commented out are fields that are not used in the
           *      codebase but have been left in for readability.
           */
          uint256 constant AlmostOneWord = 0x1f;
          uint256 constant OneWord = 0x20;
          uint256 constant TwoWords = 0x40;
          uint256 constant ThreeWords = 0x60;
          uint256 constant FreeMemoryPointerSlot = 0x40;
          uint256 constant ZeroSlot = 0x60;
          uint256 constant DefaultFreeMemoryPointer = 0x80;
          uint256 constant Slot0x80 = 0x80;
          uint256 constant Slot0xA0 = 0xa0;
          uint256 constant Slot0xC0 = 0xc0;
          // abi.encodeWithSignature("transferFrom(address,address,uint256)")
          uint256 constant ERC20_transferFrom_signature = (
              0x23b872dd00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC20_transferFrom_sig_ptr = 0x0;
          uint256 constant ERC20_transferFrom_from_ptr = 0x04;
          uint256 constant ERC20_transferFrom_to_ptr = 0x24;
          uint256 constant ERC20_transferFrom_amount_ptr = 0x44;
          uint256 constant ERC20_transferFrom_length = 0x64; // 4 + 32 * 3 == 100
          // abi.encodeWithSignature(
          //     "safeTransferFrom(address,address,uint256,uint256,bytes)"
          // )
          uint256 constant ERC1155_safeTransferFrom_signature = (
              0xf242432a00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC1155_safeTransferFrom_sig_ptr = 0x0;
          uint256 constant ERC1155_safeTransferFrom_from_ptr = 0x04;
          uint256 constant ERC1155_safeTransferFrom_to_ptr = 0x24;
          uint256 constant ERC1155_safeTransferFrom_id_ptr = 0x44;
          uint256 constant ERC1155_safeTransferFrom_amount_ptr = 0x64;
          uint256 constant ERC1155_safeTransferFrom_data_offset_ptr = 0x84;
          uint256 constant ERC1155_safeTransferFrom_data_length_ptr = 0xa4;
          uint256 constant ERC1155_safeTransferFrom_length = 0xc4; // 4 + 32 * 6 == 196
          uint256 constant ERC1155_safeTransferFrom_data_length_offset = 0xa0;
          // abi.encodeWithSignature(
          //     "safeBatchTransferFrom(address,address,uint256[],uint256[],bytes)"
          // )
          uint256 constant ERC1155_safeBatchTransferFrom_signature = (
              0x2eb2c2d600000000000000000000000000000000000000000000000000000000
          );
          bytes4 constant ERC1155_safeBatchTransferFrom_selector = bytes4(
              bytes32(ERC1155_safeBatchTransferFrom_signature)
          );
          uint256 constant ERC721_transferFrom_signature = ERC20_transferFrom_signature;
          uint256 constant ERC721_transferFrom_sig_ptr = 0x0;
          uint256 constant ERC721_transferFrom_from_ptr = 0x04;
          uint256 constant ERC721_transferFrom_to_ptr = 0x24;
          uint256 constant ERC721_transferFrom_id_ptr = 0x44;
          uint256 constant ERC721_transferFrom_length = 0x64; // 4 + 32 * 3 == 100
          // abi.encodeWithSignature("NoContract(address)")
          uint256 constant NoContract_error_signature = (
              0x5f15d67200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant NoContract_error_sig_ptr = 0x0;
          uint256 constant NoContract_error_token_ptr = 0x4;
          uint256 constant NoContract_error_length = 0x24; // 4 + 32 == 36
          // abi.encodeWithSignature(
          //     "TokenTransferGenericFailure(address,address,address,uint256,uint256)"
          // )
          uint256 constant TokenTransferGenericFailure_error_signature = (
              0xf486bc8700000000000000000000000000000000000000000000000000000000
          );
          uint256 constant TokenTransferGenericFailure_error_sig_ptr = 0x0;
          uint256 constant TokenTransferGenericFailure_error_token_ptr = 0x4;
          uint256 constant TokenTransferGenericFailure_error_from_ptr = 0x24;
          uint256 constant TokenTransferGenericFailure_error_to_ptr = 0x44;
          uint256 constant TokenTransferGenericFailure_error_id_ptr = 0x64;
          uint256 constant TokenTransferGenericFailure_error_amount_ptr = 0x84;
          // 4 + 32 * 5 == 164
          uint256 constant TokenTransferGenericFailure_error_length = 0xa4;
          // abi.encodeWithSignature(
          //     "BadReturnValueFromERC20OnTransfer(address,address,address,uint256)"
          // )
          uint256 constant BadReturnValueFromERC20OnTransfer_error_signature = (
              0x9889192300000000000000000000000000000000000000000000000000000000
          );
          uint256 constant BadReturnValueFromERC20OnTransfer_error_sig_ptr = 0x0;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_token_ptr = 0x4;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_from_ptr = 0x24;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_to_ptr = 0x44;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_amount_ptr = 0x64;
          // 4 + 32 * 4 == 132
          uint256 constant BadReturnValueFromERC20OnTransfer_error_length = 0x84;
          uint256 constant ExtraGasBuffer = 0x20;
          uint256 constant CostPerWord = 3;
          uint256 constant MemoryExpansionCoefficient = 0x200;
          // Values are offset by 32 bytes in order to write the token to the beginning
          // in the event of a revert
          uint256 constant BatchTransfer1155Params_ptr = 0x24;
          uint256 constant BatchTransfer1155Params_ids_head_ptr = 0x64;
          uint256 constant BatchTransfer1155Params_amounts_head_ptr = 0x84;
          uint256 constant BatchTransfer1155Params_data_head_ptr = 0xa4;
          uint256 constant BatchTransfer1155Params_data_length_basePtr = 0xc4;
          uint256 constant BatchTransfer1155Params_calldata_baseSize = 0xc4;
          uint256 constant BatchTransfer1155Params_ids_length_ptr = 0xc4;
          uint256 constant BatchTransfer1155Params_ids_length_offset = 0xa0;
          uint256 constant BatchTransfer1155Params_amounts_length_baseOffset = 0xc0;
          uint256 constant BatchTransfer1155Params_data_length_baseOffset = 0xe0;
          uint256 constant ConduitBatch1155Transfer_usable_head_size = 0x80;
          uint256 constant ConduitBatch1155Transfer_from_offset = 0x20;
          uint256 constant ConduitBatch1155Transfer_ids_head_offset = 0x60;
          uint256 constant ConduitBatch1155Transfer_amounts_head_offset = 0x80;
          uint256 constant ConduitBatch1155Transfer_ids_length_offset = 0xa0;
          uint256 constant ConduitBatch1155Transfer_amounts_length_baseOffset = 0xc0;
          uint256 constant ConduitBatch1155Transfer_calldata_baseSize = 0xc0;
          // Note: abbreviated version of above constant to adhere to line length limit.
          uint256 constant ConduitBatchTransfer_amounts_head_offset = 0x80;
          uint256 constant Invalid1155BatchTransferEncoding_ptr = 0x00;
          uint256 constant Invalid1155BatchTransferEncoding_length = 0x04;
          uint256 constant Invalid1155BatchTransferEncoding_selector = (
              0xeba2084c00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC1155BatchTransferGenericFailure_error_signature = (
              0xafc445e200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC1155BatchTransferGenericFailure_token_ptr = 0x04;
          uint256 constant ERC1155BatchTransferGenericFailure_ids_offset = 0xc0;
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title TokenTransferrerErrors
           */
          interface TokenTransferrerErrors {
              /**
               * @dev Revert with an error when an ERC721 transfer with amount other than
               *      one is attempted.
               */
              error InvalidERC721TransferAmount();
              /**
               * @dev Revert with an error when attempting to fulfill an order where an
               *      item has an amount of zero.
               */
              error MissingItemAmount();
              /**
               * @dev Revert with an error when attempting to fulfill an order where an
               *      item has unused parameters. This includes both the token and the
               *      identifier parameters for native transfers as well as the identifier
               *      parameter for ERC20 transfers. Note that the conduit does not
               *      perform this check, leaving it up to the calling channel to enforce
               *      when desired.
               */
              error UnusedItemParameters();
              /**
               * @dev Revert with an error when an ERC20, ERC721, or ERC1155 token
               *      transfer reverts.
               *
               * @param token      The token for which the transfer was attempted.
               * @param from       The source of the attempted transfer.
               * @param to         The recipient of the attempted transfer.
               * @param identifier The identifier for the attempted transfer.
               * @param amount     The amount for the attempted transfer.
               */
              error TokenTransferGenericFailure(
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount
              );
              /**
               * @dev Revert with an error when a batch ERC1155 token transfer reverts.
               *
               * @param token       The token for which the transfer was attempted.
               * @param from        The source of the attempted transfer.
               * @param to          The recipient of the attempted transfer.
               * @param identifiers The identifiers for the attempted transfer.
               * @param amounts     The amounts for the attempted transfer.
               */
              error ERC1155BatchTransferGenericFailure(
                  address token,
                  address from,
                  address to,
                  uint256[] identifiers,
                  uint256[] amounts
              );
              /**
               * @dev Revert with an error when an ERC20 token transfer returns a falsey
               *      value.
               *
               * @param token      The token for which the ERC20 transfer was attempted.
               * @param from       The source of the attempted ERC20 transfer.
               * @param to         The recipient of the attempted ERC20 transfer.
               * @param amount     The amount for the attempted ERC20 transfer.
               */
              error BadReturnValueFromERC20OnTransfer(
                  address token,
                  address from,
                  address to,
                  uint256 amount
              );
              /**
               * @dev Revert with an error when an account being called as an assumed
               *      contract does not have code and returns no data.
               *
               * @param account The account that should contain code.
               */
              error NoContract(address account);
              /**
               * @dev Revert with an error when attempting to execute an 1155 batch
               *      transfer using calldata not produced by default ABI encoding or with
               *      different lengths for ids and amounts arrays.
               */
              error Invalid1155BatchTransferEncoding();
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // error ChannelClosed(address channel)
          uint256 constant ChannelClosed_error_signature = (
              0x93daadf200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ChannelClosed_error_ptr = 0x00;
          uint256 constant ChannelClosed_channel_ptr = 0x4;
          uint256 constant ChannelClosed_error_length = 0x24;
          // For the mapping:
          // mapping(address => bool) channels
          // The position in storage for a particular account is:
          // keccak256(abi.encode(account, channels.slot))
          uint256 constant ChannelKey_channel_ptr = 0x00;
          uint256 constant ChannelKey_slot_ptr = 0x20;
          uint256 constant ChannelKey_length = 0x40;
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { ConduitInterface } from "../interfaces/ConduitInterface.sol";
          import { ConduitItemType } from "../conduit/lib/ConduitEnums.sol";
          import { ItemType } from "./ConsiderationEnums.sol";
          import { ReceivedItem } from "./ConsiderationStructs.sol";
          import { Verifiers } from "./Verifiers.sol";
          import { TokenTransferrer } from "./TokenTransferrer.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title Executor
           * @author 0age
           * @notice Executor contains functions related to processing executions (i.e.
           *         transferring items, either directly or via conduits).
           */
          contract Executor is Verifiers, TokenTransferrer {
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) Verifiers(conduitController) {}
              /**
               * @dev Internal function to transfer a given item, either directly or via
               *      a corresponding conduit.
               *
               * @param item        The item to transfer, including an amount and a
               *                    recipient.
               * @param from        The account supplying the item.
               * @param conduitKey  A bytes32 value indicating what corresponding conduit,
               *                    if any, to source token approvals from. The zero hash
               *                    signifies that no conduit should be used, with direct
               *                    approvals set on this contract.
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               */
              function _transfer(
                  ReceivedItem memory item,
                  address from,
                  bytes32 conduitKey,
                  bytes memory accumulator
              ) internal {
                  // If the item type indicates Ether or a native token...
                  if (item.itemType == ItemType.NATIVE) {
                      // Ensure neither the token nor the identifier parameters are set.
                      if ((uint160(item.token) | item.identifier) != 0) {
                          revert UnusedItemParameters();
                      }
                      // transfer the native tokens to the recipient.
                      _transferEth(item.recipient, item.amount);
                  } else if (item.itemType == ItemType.ERC20) {
                      // Ensure that no identifier is supplied.
                      if (item.identifier != 0) {
                          revert UnusedItemParameters();
                      }
                      // Transfer ERC20 tokens from the source to the recipient.
                      _transferERC20(
                          item.token,
                          from,
                          item.recipient,
                          item.amount,
                          conduitKey,
                          accumulator
                      );
                  } else if (item.itemType == ItemType.ERC721) {
                      // Transfer ERC721 token from the source to the recipient.
                      _transferERC721(
                          item.token,
                          from,
                          item.recipient,
                          item.identifier,
                          item.amount,
                          conduitKey,
                          accumulator
                      );
                  } else {
                      // Transfer ERC1155 token from the source to the recipient.
                      _transferERC1155(
                          item.token,
                          from,
                          item.recipient,
                          item.identifier,
                          item.amount,
                          conduitKey,
                          accumulator
                      );
                  }
              }
              /**
               * @dev Internal function to transfer an individual ERC721 or ERC1155 item
               *      from a given originator to a given recipient. The accumulator will
               *      be bypassed, meaning that this function should be utilized in cases
               *      where multiple item transfers can be accumulated into a single
               *      conduit call. Sufficient approvals must be set, either on the
               *      respective conduit or on this contract itself.
               *
               * @param itemType   The type of item to transfer, either ERC721 or ERC1155.
               * @param token      The token to transfer.
               * @param from       The originator of the transfer.
               * @param to         The recipient of the transfer.
               * @param identifier The tokenId to transfer.
               * @param amount     The amount to transfer.
               * @param conduitKey A bytes32 value indicating what corresponding conduit,
               *                   if any, to source token approvals from. The zero hash
               *                   signifies that no conduit should be used, with direct
               *                   approvals set on this contract.
               */
              function _transferIndividual721Or1155Item(
                  ItemType itemType,
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount,
                  bytes32 conduitKey
              ) internal {
                  // Determine if the transfer is to be performed via a conduit.
                  if (conduitKey != bytes32(0)) {
                      // Use free memory pointer as calldata offset for the conduit call.
                      uint256 callDataOffset;
                      // Utilize assembly to place each argument in free memory.
                      assembly {
                          // Retrieve the free memory pointer and use it as the offset.
                          callDataOffset := mload(FreeMemoryPointerSlot)
                          // Write ConduitInterface.execute.selector to memory.
                          mstore(callDataOffset, Conduit_execute_signature)
                          // Write the offset to the ConduitTransfer array in memory.
                          mstore(
                              add(
                                  callDataOffset,
                                  Conduit_execute_ConduitTransfer_offset_ptr
                              ),
                              Conduit_execute_ConduitTransfer_ptr
                          )
                          // Write the length of the ConduitTransfer array to memory.
                          mstore(
                              add(
                                  callDataOffset,
                                  Conduit_execute_ConduitTransfer_length_ptr
                              ),
                              Conduit_execute_ConduitTransfer_length
                          )
                          // Write the item type to memory.
                          mstore(
                              add(callDataOffset, Conduit_execute_transferItemType_ptr),
                              itemType
                          )
                          // Write the token to memory.
                          mstore(
                              add(callDataOffset, Conduit_execute_transferToken_ptr),
                              token
                          )
                          // Write the transfer source to memory.
                          mstore(
                              add(callDataOffset, Conduit_execute_transferFrom_ptr),
                              from
                          )
                          // Write the transfer recipient to memory.
                          mstore(add(callDataOffset, Conduit_execute_transferTo_ptr), to)
                          // Write the token identifier to memory.
                          mstore(
                              add(callDataOffset, Conduit_execute_transferIdentifier_ptr),
                              identifier
                          )
                          // Write the transfer amount to memory.
                          mstore(
                              add(callDataOffset, Conduit_execute_transferAmount_ptr),
                              amount
                          )
                      }
                      // Perform the call to the conduit.
                      _callConduitUsingOffsets(
                          conduitKey,
                          callDataOffset,
                          OneConduitExecute_size
                      );
                  } else {
                      // Otherwise, determine whether it is an ERC721 or ERC1155 item.
                      if (itemType == ItemType.ERC721) {
                          // Ensure that exactly one 721 item is being transferred.
                          if (amount != 1) {
                              revert InvalidERC721TransferAmount();
                          }
                          // Perform transfer via the token contract directly.
                          _performERC721Transfer(token, from, to, identifier);
                      } else {
                          // Perform transfer via the token contract directly.
                          _performERC1155Transfer(token, from, to, identifier, amount);
                      }
                  }
              }
              /**
               * @dev Internal function to transfer Ether or other native tokens to a
               *      given recipient.
               *
               * @param to     The recipient of the transfer.
               * @param amount The amount to transfer.
               */
              function _transferEth(address payable to, uint256 amount) internal {
                  // Ensure that the supplied amount is non-zero.
                  _assertNonZeroAmount(amount);
                  // Declare a variable indicating whether the call was successful or not.
                  bool success;
                  assembly {
                      // Transfer the ETH and store if it succeeded or not.
                      success := call(gas(), to, amount, 0, 0, 0, 0)
                  }
                  // If the call fails...
                  if (!success) {
                      // Revert and pass the revert reason along if one was returned.
                      _revertWithReasonIfOneIsReturned();
                      // Otherwise, revert with a generic error message.
                      revert EtherTransferGenericFailure(to, amount);
                  }
              }
              /**
               * @dev Internal function to transfer ERC20 tokens from a given originator
               *      to a given recipient using a given conduit if applicable. Sufficient
               *      approvals must be set on this contract or on a respective conduit.
               *
               * @param token       The ERC20 token to transfer.
               * @param from        The originator of the transfer.
               * @param to          The recipient of the transfer.
               * @param amount      The amount to transfer.
               * @param conduitKey  A bytes32 value indicating what corresponding conduit,
               *                    if any, to source token approvals from. The zero hash
               *                    signifies that no conduit should be used, with direct
               *                    approvals set on this contract.
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               */
              function _transferERC20(
                  address token,
                  address from,
                  address to,
                  uint256 amount,
                  bytes32 conduitKey,
                  bytes memory accumulator
              ) internal {
                  // Ensure that the supplied amount is non-zero.
                  _assertNonZeroAmount(amount);
                  // Trigger accumulated transfers if the conduits differ.
                  _triggerIfArmedAndNotAccumulatable(accumulator, conduitKey);
                  // If no conduit has been specified...
                  if (conduitKey == bytes32(0)) {
                      // Perform the token transfer directly.
                      _performERC20Transfer(token, from, to, amount);
                  } else {
                      // Insert the call to the conduit into the accumulator.
                      _insert(
                          conduitKey,
                          accumulator,
                          ConduitItemType.ERC20,
                          token,
                          from,
                          to,
                          uint256(0),
                          amount
                      );
                  }
              }
              /**
               * @dev Internal function to transfer a single ERC721 token from a given
               *      originator to a given recipient. Sufficient approvals must be set,
               *      either on the respective conduit or on this contract itself.
               *
               * @param token       The ERC721 token to transfer.
               * @param from        The originator of the transfer.
               * @param to          The recipient of the transfer.
               * @param identifier  The tokenId to transfer (must be 1 for ERC721).
               * @param amount      The amount to transfer.
               * @param conduitKey  A bytes32 value indicating what corresponding conduit,
               *                    if any, to source token approvals from. The zero hash
               *                    signifies that no conduit should be used, with direct
               *                    approvals set on this contract.
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               */
              function _transferERC721(
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount,
                  bytes32 conduitKey,
                  bytes memory accumulator
              ) internal {
                  // Trigger accumulated transfers if the conduits differ.
                  _triggerIfArmedAndNotAccumulatable(accumulator, conduitKey);
                  // If no conduit has been specified...
                  if (conduitKey == bytes32(0)) {
                      // Ensure that exactly one 721 item is being transferred.
                      if (amount != 1) {
                          revert InvalidERC721TransferAmount();
                      }
                      // Perform transfer via the token contract directly.
                      _performERC721Transfer(token, from, to, identifier);
                  } else {
                      // Insert the call to the conduit into the accumulator.
                      _insert(
                          conduitKey,
                          accumulator,
                          ConduitItemType.ERC721,
                          token,
                          from,
                          to,
                          identifier,
                          amount
                      );
                  }
              }
              /**
               * @dev Internal function to transfer ERC1155 tokens from a given originator
               *      to a given recipient. Sufficient approvals must be set, either on
               *      the respective conduit or on this contract itself.
               *
               * @param token       The ERC1155 token to transfer.
               * @param from        The originator of the transfer.
               * @param to          The recipient of the transfer.
               * @param identifier  The id to transfer.
               * @param amount      The amount to transfer.
               * @param conduitKey  A bytes32 value indicating what corresponding conduit,
               *                    if any, to source token approvals from. The zero hash
               *                    signifies that no conduit should be used, with direct
               *                    approvals set on this contract.
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               */
              function _transferERC1155(
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount,
                  bytes32 conduitKey,
                  bytes memory accumulator
              ) internal {
                  // Ensure that the supplied amount is non-zero.
                  _assertNonZeroAmount(amount);
                  // Trigger accumulated transfers if the conduits differ.
                  _triggerIfArmedAndNotAccumulatable(accumulator, conduitKey);
                  // If no conduit has been specified...
                  if (conduitKey == bytes32(0)) {
                      // Perform transfer via the token contract directly.
                      _performERC1155Transfer(token, from, to, identifier, amount);
                  } else {
                      // Insert the call to the conduit into the accumulator.
                      _insert(
                          conduitKey,
                          accumulator,
                          ConduitItemType.ERC1155,
                          token,
                          from,
                          to,
                          identifier,
                          amount
                      );
                  }
              }
              /**
               * @dev Internal function to trigger a call to the conduit currently held by
               *      the accumulator if the accumulator contains item transfers (i.e. it
               *      is "armed") and the supplied conduit key does not match the key held
               *      by the accumulator.
               *
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               * @param conduitKey  A bytes32 value indicating what corresponding conduit,
               *                    if any, to source token approvals from. The zero hash
               *                    signifies that no conduit should be used, with direct
               *                    approvals set on this contract.
               */
              function _triggerIfArmedAndNotAccumulatable(
                  bytes memory accumulator,
                  bytes32 conduitKey
              ) internal {
                  // Retrieve the current conduit key from the accumulator.
                  bytes32 accumulatorConduitKey = _getAccumulatorConduitKey(accumulator);
                  // Perform conduit call if the set key does not match the supplied key.
                  if (accumulatorConduitKey != conduitKey) {
                      _triggerIfArmed(accumulator);
                  }
              }
              /**
               * @dev Internal function to trigger a call to the conduit currently held by
               *      the accumulator if the accumulator contains item transfers (i.e. it
               *      is "armed").
               *
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               */
              function _triggerIfArmed(bytes memory accumulator) internal {
                  // Exit if the accumulator is not "armed".
                  if (accumulator.length != AccumulatorArmed) {
                      return;
                  }
                  // Retrieve the current conduit key from the accumulator.
                  bytes32 accumulatorConduitKey = _getAccumulatorConduitKey(accumulator);
                  // Perform conduit call.
                  _trigger(accumulatorConduitKey, accumulator);
              }
              /**
               * @dev Internal function to trigger a call to the conduit corresponding to
               *      a given conduit key, supplying all accumulated item transfers. The
               *      accumulator will be "disarmed" and reset in the process.
               *
               * @param conduitKey  A bytes32 value indicating what corresponding conduit,
               *                    if any, to source token approvals from. The zero hash
               *                    signifies that no conduit should be used, with direct
               *                    approvals set on this contract.
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               */
              function _trigger(bytes32 conduitKey, bytes memory accumulator) internal {
                  // Declare variables for offset in memory & size of calldata to conduit.
                  uint256 callDataOffset;
                  uint256 callDataSize;
                  // Call the conduit with all the accumulated transfers.
                  assembly {
                      // Call begins at third word; the first is length or "armed" status,
                      // and the second is the current conduit key.
                      callDataOffset := add(accumulator, TwoWords)
                      // 68 + items * 192
                      callDataSize := add(
                          Accumulator_array_offset_ptr,
                          mul(
                              mload(add(accumulator, Accumulator_array_length_ptr)),
                              Conduit_transferItem_size
                          )
                      )
                  }
                  // Call conduit derived from conduit key & supply accumulated transfers.
                  _callConduitUsingOffsets(conduitKey, callDataOffset, callDataSize);
                  // Reset accumulator length to signal that it is now "disarmed".
                  assembly {
                      mstore(accumulator, AccumulatorDisarmed)
                  }
              }
              /**
               * @dev Internal function to perform a call to the conduit corresponding to
               *      a given conduit key based on the offset and size of the calldata in
               *      question in memory.
               *
               * @param conduitKey     A bytes32 value indicating what corresponding
               *                       conduit, if any, to source token approvals from.
               *                       The zero hash signifies that no conduit should be
               *                       used, with direct approvals set on this contract.
               * @param callDataOffset The memory pointer where calldata is contained.
               * @param callDataSize   The size of calldata in memory.
               */
              function _callConduitUsingOffsets(
                  bytes32 conduitKey,
                  uint256 callDataOffset,
                  uint256 callDataSize
              ) internal {
                  // Derive the address of the conduit using the conduit key.
                  address conduit = _deriveConduit(conduitKey);
                  bool success;
                  bytes4 result;
                  // call the conduit.
                  assembly {
                      // Ensure first word of scratch space is empty.
                      mstore(0, 0)
                      // Perform call, placing first word of return data in scratch space.
                      success := call(
                          gas(),
                          conduit,
                          0,
                          callDataOffset,
                          callDataSize,
                          0,
                          OneWord
                      )
                      // Take value from scratch space and place it on the stack.
                      result := mload(0)
                  }
                  // If the call failed...
                  if (!success) {
                      // Pass along whatever revert reason was given by the conduit.
                      _revertWithReasonIfOneIsReturned();
                      // Otherwise, revert with a generic error.
                      revert InvalidCallToConduit(conduit);
                  }
                  // Ensure result was extracted and matches EIP-1271 magic value.
                  if (result != ConduitInterface.execute.selector) {
                      revert InvalidConduit(conduitKey, conduit);
                  }
              }
              /**
               * @dev Internal pure function to retrieve the current conduit key set for
               *      the accumulator.
               *
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               *
               * @return accumulatorConduitKey The conduit key currently set for the
               *                               accumulator.
               */
              function _getAccumulatorConduitKey(bytes memory accumulator)
                  internal
                  pure
                  returns (bytes32 accumulatorConduitKey)
              {
                  // Retrieve the current conduit key from the accumulator.
                  assembly {
                      accumulatorConduitKey := mload(
                          add(accumulator, Accumulator_conduitKey_ptr)
                      )
                  }
              }
              /**
               * @dev Internal pure function to place an item transfer into an accumulator
               *      that collects a series of transfers to execute against a given
               *      conduit in a single call.
               *
               * @param conduitKey  A bytes32 value indicating what corresponding conduit,
               *                    if any, to source token approvals from. The zero hash
               *                    signifies that no conduit should be used, with direct
               *                    approvals set on this contract.
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               * @param itemType    The type of the item to transfer.
               * @param token       The token to transfer.
               * @param from        The originator of the transfer.
               * @param to          The recipient of the transfer.
               * @param identifier  The tokenId to transfer.
               * @param amount      The amount to transfer.
               */
              function _insert(
                  bytes32 conduitKey,
                  bytes memory accumulator,
                  ConduitItemType itemType,
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount
              ) internal pure {
                  uint256 elements;
                  // "Arm" and prime accumulator if it's not already armed. The sentinel
                  // value is held in the length of the accumulator array.
                  if (accumulator.length == AccumulatorDisarmed) {
                      elements = 1;
                      bytes4 selector = ConduitInterface.execute.selector;
                      assembly {
                          mstore(accumulator, AccumulatorArmed) // "arm" the accumulator.
                          mstore(add(accumulator, Accumulator_conduitKey_ptr), conduitKey)
                          mstore(add(accumulator, Accumulator_selector_ptr), selector)
                          mstore(
                              add(accumulator, Accumulator_array_offset_ptr),
                              Accumulator_array_offset
                          )
                          mstore(add(accumulator, Accumulator_array_length_ptr), elements)
                      }
                  } else {
                      // Otherwise, increase the number of elements by one.
                      assembly {
                          elements := add(
                              mload(add(accumulator, Accumulator_array_length_ptr)),
                              1
                          )
                          mstore(add(accumulator, Accumulator_array_length_ptr), elements)
                      }
                  }
                  // Insert the item.
                  assembly {
                      let itemPointer := sub(
                          add(accumulator, mul(elements, Conduit_transferItem_size)),
                          Accumulator_itemSizeOffsetDifference
                      )
                      mstore(itemPointer, itemType)
                      mstore(add(itemPointer, Conduit_transferItem_token_ptr), token)
                      mstore(add(itemPointer, Conduit_transferItem_from_ptr), from)
                      mstore(add(itemPointer, Conduit_transferItem_to_ptr), to)
                      mstore(
                          add(itemPointer, Conduit_transferItem_identifier_ptr),
                          identifier
                      )
                      mstore(add(itemPointer, Conduit_transferItem_amount_ptr), amount)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // prettier-ignore
          enum OrderType {
              // 0: no partial fills, anyone can execute
              FULL_OPEN,
              // 1: partial fills supported, anyone can execute
              PARTIAL_OPEN,
              // 2: no partial fills, only offerer or zone can execute
              FULL_RESTRICTED,
              // 3: partial fills supported, only offerer or zone can execute
              PARTIAL_RESTRICTED
          }
          // prettier-ignore
          enum BasicOrderType {
              // 0: no partial fills, anyone can execute
              ETH_TO_ERC721_FULL_OPEN,
              // 1: partial fills supported, anyone can execute
              ETH_TO_ERC721_PARTIAL_OPEN,
              // 2: no partial fills, only offerer or zone can execute
              ETH_TO_ERC721_FULL_RESTRICTED,
              // 3: partial fills supported, only offerer or zone can execute
              ETH_TO_ERC721_PARTIAL_RESTRICTED,
              // 4: no partial fills, anyone can execute
              ETH_TO_ERC1155_FULL_OPEN,
              // 5: partial fills supported, anyone can execute
              ETH_TO_ERC1155_PARTIAL_OPEN,
              // 6: no partial fills, only offerer or zone can execute
              ETH_TO_ERC1155_FULL_RESTRICTED,
              // 7: partial fills supported, only offerer or zone can execute
              ETH_TO_ERC1155_PARTIAL_RESTRICTED,
              // 8: no partial fills, anyone can execute
              ERC20_TO_ERC721_FULL_OPEN,
              // 9: partial fills supported, anyone can execute
              ERC20_TO_ERC721_PARTIAL_OPEN,
              // 10: no partial fills, only offerer or zone can execute
              ERC20_TO_ERC721_FULL_RESTRICTED,
              // 11: partial fills supported, only offerer or zone can execute
              ERC20_TO_ERC721_PARTIAL_RESTRICTED,
              // 12: no partial fills, anyone can execute
              ERC20_TO_ERC1155_FULL_OPEN,
              // 13: partial fills supported, anyone can execute
              ERC20_TO_ERC1155_PARTIAL_OPEN,
              // 14: no partial fills, only offerer or zone can execute
              ERC20_TO_ERC1155_FULL_RESTRICTED,
              // 15: partial fills supported, only offerer or zone can execute
              ERC20_TO_ERC1155_PARTIAL_RESTRICTED,
              // 16: no partial fills, anyone can execute
              ERC721_TO_ERC20_FULL_OPEN,
              // 17: partial fills supported, anyone can execute
              ERC721_TO_ERC20_PARTIAL_OPEN,
              // 18: no partial fills, only offerer or zone can execute
              ERC721_TO_ERC20_FULL_RESTRICTED,
              // 19: partial fills supported, only offerer or zone can execute
              ERC721_TO_ERC20_PARTIAL_RESTRICTED,
              // 20: no partial fills, anyone can execute
              ERC1155_TO_ERC20_FULL_OPEN,
              // 21: partial fills supported, anyone can execute
              ERC1155_TO_ERC20_PARTIAL_OPEN,
              // 22: no partial fills, only offerer or zone can execute
              ERC1155_TO_ERC20_FULL_RESTRICTED,
              // 23: partial fills supported, only offerer or zone can execute
              ERC1155_TO_ERC20_PARTIAL_RESTRICTED
          }
          // prettier-ignore
          enum BasicOrderRouteType {
              // 0: provide Ether (or other native token) to receive offered ERC721 item.
              ETH_TO_ERC721,
              // 1: provide Ether (or other native token) to receive offered ERC1155 item.
              ETH_TO_ERC1155,
              // 2: provide ERC20 item to receive offered ERC721 item.
              ERC20_TO_ERC721,
              // 3: provide ERC20 item to receive offered ERC1155 item.
              ERC20_TO_ERC1155,
              // 4: provide ERC721 item to receive offered ERC20 item.
              ERC721_TO_ERC20,
              // 5: provide ERC1155 item to receive offered ERC20 item.
              ERC1155_TO_ERC20
          }
          // prettier-ignore
          enum ItemType {
              // 0: ETH on mainnet, MATIC on polygon, etc.
              NATIVE,
              // 1: ERC20 items (ERC777 and ERC20 analogues could also technically work)
              ERC20,
              // 2: ERC721 items
              ERC721,
              // 3: ERC1155 items
              ERC1155,
              // 4: ERC721 items where a number of tokenIds are supported
              ERC721_WITH_CRITERIA,
              // 5: ERC1155 items where a number of ids are supported
              ERC1155_WITH_CRITERIA
          }
          // prettier-ignore
          enum Side {
              // 0: Items that can be spent
              OFFER,
              // 1: Items that must be received
              CONSIDERATION
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // prettier-ignore
          import {
              OrderType,
              BasicOrderType,
              ItemType,
              Side
          } from "./ConsiderationEnums.sol";
          /**
           * @dev An order contains eleven components: an offerer, a zone (or account that
           *      can cancel the order or restrict who can fulfill the order depending on
           *      the type), the order type (specifying partial fill support as well as
           *      restricted order status), the start and end time, a hash that will be
           *      provided to the zone when validating restricted orders, a salt, a key
           *      corresponding to a given conduit, a counter, and an arbitrary number of
           *      offer items that can be spent along with consideration items that must
           *      be received by their respective recipient.
           */
          struct OrderComponents {
              address offerer;
              address zone;
              OfferItem[] offer;
              ConsiderationItem[] consideration;
              OrderType orderType;
              uint256 startTime;
              uint256 endTime;
              bytes32 zoneHash;
              uint256 salt;
              bytes32 conduitKey;
              uint256 counter;
          }
          /**
           * @dev An offer item has five components: an item type (ETH or other native
           *      tokens, ERC20, ERC721, and ERC1155, as well as criteria-based ERC721 and
           *      ERC1155), a token address, a dual-purpose "identifierOrCriteria"
           *      component that will either represent a tokenId or a merkle root
           *      depending on the item type, and a start and end amount that support
           *      increasing or decreasing amounts over the duration of the respective
           *      order.
           */
          struct OfferItem {
              ItemType itemType;
              address token;
              uint256 identifierOrCriteria;
              uint256 startAmount;
              uint256 endAmount;
          }
          /**
           * @dev A consideration item has the same five components as an offer item and
           *      an additional sixth component designating the required recipient of the
           *      item.
           */
          struct ConsiderationItem {
              ItemType itemType;
              address token;
              uint256 identifierOrCriteria;
              uint256 startAmount;
              uint256 endAmount;
              address payable recipient;
          }
          /**
           * @dev A spent item is translated from a utilized offer item and has four
           *      components: an item type (ETH or other native tokens, ERC20, ERC721, and
           *      ERC1155), a token address, a tokenId, and an amount.
           */
          struct SpentItem {
              ItemType itemType;
              address token;
              uint256 identifier;
              uint256 amount;
          }
          /**
           * @dev A received item is translated from a utilized consideration item and has
           *      the same four components as a spent item, as well as an additional fifth
           *      component designating the required recipient of the item.
           */
          struct ReceivedItem {
              ItemType itemType;
              address token;
              uint256 identifier;
              uint256 amount;
              address payable recipient;
          }
          /**
           * @dev For basic orders involving ETH / native / ERC20 <=> ERC721 / ERC1155
           *      matching, a group of six functions may be called that only requires a
           *      subset of the usual order arguments. Note the use of a "basicOrderType"
           *      enum; this represents both the usual order type as well as the "route"
           *      of the basic order (a simple derivation function for the basic order
           *      type is `basicOrderType = orderType + (4 * basicOrderRoute)`.)
           */
          struct BasicOrderParameters {
              // calldata offset
              address considerationToken; // 0x24
              uint256 considerationIdentifier; // 0x44
              uint256 considerationAmount; // 0x64
              address payable offerer; // 0x84
              address zone; // 0xa4
              address offerToken; // 0xc4
              uint256 offerIdentifier; // 0xe4
              uint256 offerAmount; // 0x104
              BasicOrderType basicOrderType; // 0x124
              uint256 startTime; // 0x144
              uint256 endTime; // 0x164
              bytes32 zoneHash; // 0x184
              uint256 salt; // 0x1a4
              bytes32 offererConduitKey; // 0x1c4
              bytes32 fulfillerConduitKey; // 0x1e4
              uint256 totalOriginalAdditionalRecipients; // 0x204
              AdditionalRecipient[] additionalRecipients; // 0x224
              bytes signature; // 0x244
              // Total length, excluding dynamic array data: 0x264 (580)
          }
          /**
           * @dev Basic orders can supply any number of additional recipients, with the
           *      implied assumption that they are supplied from the offered ETH (or other
           *      native token) or ERC20 token for the order.
           */
          struct AdditionalRecipient {
              uint256 amount;
              address payable recipient;
          }
          /**
           * @dev The full set of order components, with the exception of the counter,
           *      must be supplied when fulfilling more sophisticated orders or groups of
           *      orders. The total number of original consideration items must also be
           *      supplied, as the caller may specify additional consideration items.
           */
          struct OrderParameters {
              address offerer; // 0x00
              address zone; // 0x20
              OfferItem[] offer; // 0x40
              ConsiderationItem[] consideration; // 0x60
              OrderType orderType; // 0x80
              uint256 startTime; // 0xa0
              uint256 endTime; // 0xc0
              bytes32 zoneHash; // 0xe0
              uint256 salt; // 0x100
              bytes32 conduitKey; // 0x120
              uint256 totalOriginalConsiderationItems; // 0x140
              // offer.length                          // 0x160
          }
          /**
           * @dev Orders require a signature in addition to the other order parameters.
           */
          struct Order {
              OrderParameters parameters;
              bytes signature;
          }
          /**
           * @dev Advanced orders include a numerator (i.e. a fraction to attempt to fill)
           *      and a denominator (the total size of the order) in addition to the
           *      signature and other order parameters. It also supports an optional field
           *      for supplying extra data; this data will be included in a staticcall to
           *      `isValidOrderIncludingExtraData` on the zone for the order if the order
           *      type is restricted and the offerer or zone are not the caller.
           */
          struct AdvancedOrder {
              OrderParameters parameters;
              uint120 numerator;
              uint120 denominator;
              bytes signature;
              bytes extraData;
          }
          /**
           * @dev Orders can be validated (either explicitly via `validate`, or as a
           *      consequence of a full or partial fill), specifically cancelled (they can
           *      also be cancelled in bulk via incrementing a per-zone counter), and
           *      partially or fully filled (with the fraction filled represented by a
           *      numerator and denominator).
           */
          struct OrderStatus {
              bool isValidated;
              bool isCancelled;
              uint120 numerator;
              uint120 denominator;
          }
          /**
           * @dev A criteria resolver specifies an order, side (offer vs. consideration),
           *      and item index. It then provides a chosen identifier (i.e. tokenId)
           *      alongside a merkle proof demonstrating the identifier meets the required
           *      criteria.
           */
          struct CriteriaResolver {
              uint256 orderIndex;
              Side side;
              uint256 index;
              uint256 identifier;
              bytes32[] criteriaProof;
          }
          /**
           * @dev A fulfillment is applied to a group of orders. It decrements a series of
           *      offer and consideration items, then generates a single execution
           *      element. A given fulfillment can be applied to as many offer and
           *      consideration items as desired, but must contain at least one offer and
           *      at least one consideration that match. The fulfillment must also remain
           *      consistent on all key parameters across all offer items (same offerer,
           *      token, type, tokenId, and conduit preference) as well as across all
           *      consideration items (token, type, tokenId, and recipient).
           */
          struct Fulfillment {
              FulfillmentComponent[] offerComponents;
              FulfillmentComponent[] considerationComponents;
          }
          /**
           * @dev Each fulfillment component contains one index referencing a specific
           *      order and another referencing a specific offer or consideration item.
           */
          struct FulfillmentComponent {
              uint256 orderIndex;
              uint256 itemIndex;
          }
          /**
           * @dev An execution is triggered once all consideration items have been zeroed
           *      out. It sends the item in question from the offerer to the item's
           *      recipient, optionally sourcing approvals from either this contract
           *      directly or from the offerer's chosen conduit if one is specified. An
           *      execution is not provided as an argument, but rather is derived via
           *      orders, criteria resolvers, and fulfillments (where the total number of
           *      executions will be less than or equal to the total number of indicated
           *      fulfillments) and returned as part of `matchOrders`.
           */
          struct Execution {
              ReceivedItem item;
              address offerer;
              bytes32 conduitKey;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { OrderStatus } from "./ConsiderationStructs.sol";
          import { Assertions } from "./Assertions.sol";
          import { SignatureVerification } from "./SignatureVerification.sol";
          /**
           * @title Verifiers
           * @author 0age
           * @notice Verifiers contains functions for performing verifications.
           */
          contract Verifiers is Assertions, SignatureVerification {
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) Assertions(conduitController) {}
              /**
               * @dev Internal view function to ensure that the current time falls within
               *      an order's valid timespan.
               *
               * @param startTime       The time at which the order becomes active.
               * @param endTime         The time at which the order becomes inactive.
               * @param revertOnInvalid A boolean indicating whether to revert if the
               *                        order is not active.
               *
               * @return valid A boolean indicating whether the order is active.
               */
              function _verifyTime(
                  uint256 startTime,
                  uint256 endTime,
                  bool revertOnInvalid
              ) internal view returns (bool valid) {
                  // Revert if order's timespan hasn't started yet or has already ended.
                  if (startTime > block.timestamp || endTime <= block.timestamp) {
                      // Only revert if revertOnInvalid has been supplied as true.
                      if (revertOnInvalid) {
                          revert InvalidTime();
                      }
                      // Return false as the order is invalid.
                      return false;
                  }
                  // Return true as the order time is valid.
                  valid = true;
              }
              /**
               * @dev Internal view function to verify the signature of an order. An
               *      ERC-1271 fallback will be attempted if either the signature length
               *      is not 32 or 33 bytes or if the recovered signer does not match the
               *      supplied offerer. Note that in cases where a 32 or 33 byte signature
               *      is supplied, only standard ECDSA signatures that recover to a
               *      non-zero address are supported.
               *
               * @param offerer   The offerer for the order.
               * @param orderHash The order hash.
               * @param signature A signature from the offerer indicating that the order
               *                  has been approved.
               */
              function _verifySignature(
                  address offerer,
                  bytes32 orderHash,
                  bytes memory signature
              ) internal view {
                  // Skip signature verification if the offerer is the caller.
                  if (offerer == msg.sender) {
                      return;
                  }
                  // Derive EIP-712 digest using the domain separator and the order hash.
                  bytes32 digest = _deriveEIP712Digest(_domainSeparator(), orderHash);
                  // Ensure that the signature for the digest is valid for the offerer.
                  _assertValidSignature(offerer, digest, signature);
              }
              /**
               * @dev Internal view function to validate that a given order is fillable
               *      and not cancelled based on the order status.
               *
               * @param orderHash       The order hash.
               * @param orderStatus     The status of the order, including whether it has
               *                        been cancelled and the fraction filled.
               * @param onlyAllowUnused A boolean flag indicating whether partial fills
               *                        are supported by the calling function.
               * @param revertOnInvalid A boolean indicating whether to revert if the
               *                        order has been cancelled or filled beyond the
               *                        allowable amount.
               *
               * @return valid A boolean indicating whether the order is valid.
               */
              function _verifyOrderStatus(
                  bytes32 orderHash,
                  OrderStatus storage orderStatus,
                  bool onlyAllowUnused,
                  bool revertOnInvalid
              ) internal view returns (bool valid) {
                  // Ensure that the order has not been cancelled.
                  if (orderStatus.isCancelled) {
                      // Only revert if revertOnInvalid has been supplied as true.
                      if (revertOnInvalid) {
                          revert OrderIsCancelled(orderHash);
                      }
                      // Return false as the order status is invalid.
                      return false;
                  }
                  // Read order status numerator from storage and place on stack.
                  uint256 orderStatusNumerator = orderStatus.numerator;
                  // If the order is not entirely unused...
                  if (orderStatusNumerator != 0) {
                      // ensure the order has not been partially filled when not allowed.
                      if (onlyAllowUnused) {
                          // Always revert on partial fills when onlyAllowUnused is true.
                          revert OrderPartiallyFilled(orderHash);
                      }
                      // Otherwise, ensure that order has not been entirely filled.
                      else if (orderStatusNumerator >= orderStatus.denominator) {
                          // Only revert if revertOnInvalid has been supplied as true.
                          if (revertOnInvalid) {
                              revert OrderAlreadyFilled(orderHash);
                          }
                          // Return false as the order status is invalid.
                          return false;
                      }
                  }
                  // Return true as the order status is valid.
                  valid = true;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /*
           * -------------------------- Disambiguation & Other Notes ---------------------
           *    - The term "head" is used as it is in the documentation for ABI encoding,
           *      but only in reference to dynamic types, i.e. it always refers to the
           *      offset or pointer to the body of a dynamic type. In calldata, the head
           *      is always an offset (relative to the parent object), while in memory,
           *      the head is always the pointer to the body. More information found here:
           *      https://docs.soliditylang.org/en/v0.8.14/abi-spec.html#argument-encoding
           *        - Note that the length of an array is separate from and precedes the
           *          head of the array.
           *
           *    - The term "body" is used in place of the term "head" used in the ABI
           *      documentation. It refers to the start of the data for a dynamic type,
           *      e.g. the first word of a struct or the first word of the first element
           *      in an array.
           *
           *    - The term "pointer" is used to describe the absolute position of a value
           *      and never an offset relative to another value.
           *        - The suffix "_ptr" refers to a memory pointer.
           *        - The suffix "_cdPtr" refers to a calldata pointer.
           *
           *    - The term "offset" is used to describe the position of a value relative
           *      to some parent value. For example, OrderParameters_conduit_offset is the
           *      offset to the "conduit" value in the OrderParameters struct relative to
           *      the start of the body.
           *        - Note: Offsets are used to derive pointers.
           *
           *    - Some structs have pointers defined for all of their fields in this file.
           *      Lines which are commented out are fields that are not used in the
           *      codebase but have been left in for readability.
           */
          // Declare constants for name, version, and reentrancy sentinel values.
          // Name is right padded, so it touches the length which is left padded. This
          // enables writing both values at once. Length goes at byte 95 in memory, and
          // name fills bytes 96-109, so both values can be written left-padded to 77.
          uint256 constant NameLengthPtr = 77;
          uint256 constant NameWithLength = 0x0d436F6E73696465726174696F6E;
          uint256 constant Version = 0x312e31;
          uint256 constant Version_length = 3;
          uint256 constant Version_shift = 0xe8;
          uint256 constant _NOT_ENTERED = 1;
          uint256 constant _ENTERED = 2;
          // Common Offsets
          // Offsets for identically positioned fields shared by:
          // OfferItem, ConsiderationItem, SpentItem, ReceivedItem
          uint256 constant Common_token_offset = 0x20;
          uint256 constant Common_identifier_offset = 0x40;
          uint256 constant Common_amount_offset = 0x60;
          uint256 constant ReceivedItem_size = 0xa0;
          uint256 constant ReceivedItem_amount_offset = 0x60;
          uint256 constant ReceivedItem_recipient_offset = 0x80;
          uint256 constant ReceivedItem_CommonParams_size = 0x60;
          uint256 constant ConsiderationItem_recipient_offset = 0xa0;
          // Store the same constant in an abbreviated format for a line length fix.
          uint256 constant ConsiderItem_recipient_offset = 0xa0;
          uint256 constant Execution_offerer_offset = 0x20;
          uint256 constant Execution_conduit_offset = 0x40;
          uint256 constant InvalidFulfillmentComponentData_error_signature = (
              0x7fda727900000000000000000000000000000000000000000000000000000000
          );
          uint256 constant InvalidFulfillmentComponentData_error_len = 0x04;
          uint256 constant Panic_error_signature = (
              0x4e487b7100000000000000000000000000000000000000000000000000000000
          );
          uint256 constant Panic_error_offset = 0x04;
          uint256 constant Panic_error_length = 0x24;
          uint256 constant Panic_arithmetic = 0x11;
          uint256 constant MissingItemAmount_error_signature = (
              0x91b3e51400000000000000000000000000000000000000000000000000000000
          );
          uint256 constant MissingItemAmount_error_len = 0x04;
          uint256 constant OrderParameters_offer_head_offset = 0x40;
          uint256 constant OrderParameters_consideration_head_offset = 0x60;
          uint256 constant OrderParameters_conduit_offset = 0x120;
          uint256 constant OrderParameters_counter_offset = 0x140;
          uint256 constant Fulfillment_itemIndex_offset = 0x20;
          uint256 constant AdvancedOrder_numerator_offset = 0x20;
          uint256 constant AlmostOneWord = 0x1f;
          uint256 constant OneWord = 0x20;
          uint256 constant TwoWords = 0x40;
          uint256 constant ThreeWords = 0x60;
          uint256 constant FourWords = 0x80;
          uint256 constant FiveWords = 0xa0;
          uint256 constant FreeMemoryPointerSlot = 0x40;
          uint256 constant ZeroSlot = 0x60;
          uint256 constant DefaultFreeMemoryPointer = 0x80;
          uint256 constant Slot0x80 = 0x80;
          uint256 constant Slot0xA0 = 0xa0;
          uint256 constant BasicOrder_endAmount_cdPtr = 0x104;
          uint256 constant BasicOrder_common_params_size = 0xa0;
          uint256 constant BasicOrder_considerationHashesArray_ptr = 0x160;
          uint256 constant EIP712_Order_size = 0x180;
          uint256 constant EIP712_OfferItem_size = 0xc0;
          uint256 constant EIP712_ConsiderationItem_size = 0xe0;
          uint256 constant AdditionalRecipients_size = 0x40;
          uint256 constant EIP712_DomainSeparator_offset = 0x02;
          uint256 constant EIP712_OrderHash_offset = 0x22;
          uint256 constant EIP712_DigestPayload_size = 0x42;
          uint256 constant receivedItemsHash_ptr = 0x60;
          /*
           *  Memory layout in _prepareBasicFulfillmentFromCalldata of
           *  data for OrderFulfilled
           *
           *   event OrderFulfilled(
           *     bytes32 orderHash,
           *     address indexed offerer,
           *     address indexed zone,
           *     address fulfiller,
           *     SpentItem[] offer,
           *       > (itemType, token, id, amount)
           *     ReceivedItem[] consideration
           *       > (itemType, token, id, amount, recipient)
           *   )
           *
           *  - 0x00: orderHash
           *  - 0x20: fulfiller
           *  - 0x40: offer offset (0x80)
           *  - 0x60: consideration offset (0x120)
           *  - 0x80: offer.length (1)
           *  - 0xa0: offerItemType
           *  - 0xc0: offerToken
           *  - 0xe0: offerIdentifier
           *  - 0x100: offerAmount
           *  - 0x120: consideration.length (1 + additionalRecipients.length)
           *  - 0x140: considerationItemType
           *  - 0x160: considerationToken
           *  - 0x180: considerationIdentifier
           *  - 0x1a0: considerationAmount
           *  - 0x1c0: considerationRecipient
           *  - ...
           */
          // Minimum length of the OrderFulfilled event data.
          // Must be added to the size of the ReceivedItem array for additionalRecipients
          // (0xa0 * additionalRecipients.length) to calculate full size of the buffer.
          uint256 constant OrderFulfilled_baseSize = 0x1e0;
          uint256 constant OrderFulfilled_selector = (
              0x9d9af8e38d66c62e2c12f0225249fd9d721c54b83f48d9352c97c6cacdcb6f31
          );
          // Minimum offset in memory to OrderFulfilled event data.
          // Must be added to the size of the EIP712 hash array for additionalRecipients
          // (32 * additionalRecipients.length) to calculate the pointer to event data.
          uint256 constant OrderFulfilled_baseOffset = 0x180;
          uint256 constant OrderFulfilled_consideration_length_baseOffset = 0x2a0;
          uint256 constant OrderFulfilled_offer_length_baseOffset = 0x200;
          // uint256 constant OrderFulfilled_orderHash_offset = 0x00;
          uint256 constant OrderFulfilled_fulfiller_offset = 0x20;
          uint256 constant OrderFulfilled_offer_head_offset = 0x40;
          uint256 constant OrderFulfilled_offer_body_offset = 0x80;
          uint256 constant OrderFulfilled_consideration_head_offset = 0x60;
          uint256 constant OrderFulfilled_consideration_body_offset = 0x120;
          // BasicOrderParameters
          uint256 constant BasicOrder_parameters_cdPtr = 0x04;
          uint256 constant BasicOrder_considerationToken_cdPtr = 0x24;
          // uint256 constant BasicOrder_considerationIdentifier_cdPtr = 0x44;
          uint256 constant BasicOrder_considerationAmount_cdPtr = 0x64;
          uint256 constant BasicOrder_offerer_cdPtr = 0x84;
          uint256 constant BasicOrder_zone_cdPtr = 0xa4;
          uint256 constant BasicOrder_offerToken_cdPtr = 0xc4;
          // uint256 constant BasicOrder_offerIdentifier_cdPtr = 0xe4;
          uint256 constant BasicOrder_offerAmount_cdPtr = 0x104;
          uint256 constant BasicOrder_basicOrderType_cdPtr = 0x124;
          uint256 constant BasicOrder_startTime_cdPtr = 0x144;
          // uint256 constant BasicOrder_endTime_cdPtr = 0x164;
          // uint256 constant BasicOrder_zoneHash_cdPtr = 0x184;
          // uint256 constant BasicOrder_salt_cdPtr = 0x1a4;
          uint256 constant BasicOrder_offererConduit_cdPtr = 0x1c4;
          uint256 constant BasicOrder_fulfillerConduit_cdPtr = 0x1e4;
          uint256 constant BasicOrder_totalOriginalAdditionalRecipients_cdPtr = 0x204;
          uint256 constant BasicOrder_additionalRecipients_head_cdPtr = 0x224;
          uint256 constant BasicOrder_signature_cdPtr = 0x244;
          uint256 constant BasicOrder_additionalRecipients_length_cdPtr = 0x264;
          uint256 constant BasicOrder_additionalRecipients_data_cdPtr = 0x284;
          uint256 constant BasicOrder_parameters_ptr = 0x20;
          uint256 constant BasicOrder_basicOrderType_range = 0x18; // 24 values
          /*
           *  Memory layout in _prepareBasicFulfillmentFromCalldata of
           *  EIP712 data for ConsiderationItem
           *   - 0x80: ConsiderationItem EIP-712 typehash (constant)
           *   - 0xa0: itemType
           *   - 0xc0: token
           *   - 0xe0: identifier
           *   - 0x100: startAmount
           *   - 0x120: endAmount
           *   - 0x140: recipient
           */
          uint256 constant BasicOrder_considerationItem_typeHash_ptr = 0x80; // memoryPtr
          uint256 constant BasicOrder_considerationItem_itemType_ptr = 0xa0;
          uint256 constant BasicOrder_considerationItem_token_ptr = 0xc0;
          uint256 constant BasicOrder_considerationItem_identifier_ptr = 0xe0;
          uint256 constant BasicOrder_considerationItem_startAmount_ptr = 0x100;
          uint256 constant BasicOrder_considerationItem_endAmount_ptr = 0x120;
          // uint256 constant BasicOrder_considerationItem_recipient_ptr = 0x140;
          /*
           *  Memory layout in _prepareBasicFulfillmentFromCalldata of
           *  EIP712 data for OfferItem
           *   - 0x80:  OfferItem EIP-712 typehash (constant)
           *   - 0xa0:  itemType
           *   - 0xc0:  token
           *   - 0xe0:  identifier (reused for offeredItemsHash)
           *   - 0x100: startAmount
           *   - 0x120: endAmount
           */
          uint256 constant BasicOrder_offerItem_typeHash_ptr = DefaultFreeMemoryPointer;
          uint256 constant BasicOrder_offerItem_itemType_ptr = 0xa0;
          uint256 constant BasicOrder_offerItem_token_ptr = 0xc0;
          // uint256 constant BasicOrder_offerItem_identifier_ptr = 0xe0;
          // uint256 constant BasicOrder_offerItem_startAmount_ptr = 0x100;
          uint256 constant BasicOrder_offerItem_endAmount_ptr = 0x120;
          /*
           *  Memory layout in _prepareBasicFulfillmentFromCalldata of
           *  EIP712 data for Order
           *   - 0x80:   Order EIP-712 typehash (constant)
           *   - 0xa0:   orderParameters.offerer
           *   - 0xc0:   orderParameters.zone
           *   - 0xe0:   keccak256(abi.encodePacked(offerHashes))
           *   - 0x100:  keccak256(abi.encodePacked(considerationHashes))
           *   - 0x120:  orderType
           *   - 0x140:  startTime
           *   - 0x160:  endTime
           *   - 0x180:  zoneHash
           *   - 0x1a0:  salt
           *   - 0x1c0:  conduit
           *   - 0x1e0:  _counters[orderParameters.offerer] (from storage)
           */
          uint256 constant BasicOrder_order_typeHash_ptr = 0x80;
          uint256 constant BasicOrder_order_offerer_ptr = 0xa0;
          // uint256 constant BasicOrder_order_zone_ptr = 0xc0;
          uint256 constant BasicOrder_order_offerHashes_ptr = 0xe0;
          uint256 constant BasicOrder_order_considerationHashes_ptr = 0x100;
          uint256 constant BasicOrder_order_orderType_ptr = 0x120;
          uint256 constant BasicOrder_order_startTime_ptr = 0x140;
          // uint256 constant BasicOrder_order_endTime_ptr = 0x160;
          // uint256 constant BasicOrder_order_zoneHash_ptr = 0x180;
          // uint256 constant BasicOrder_order_salt_ptr = 0x1a0;
          // uint256 constant BasicOrder_order_conduitKey_ptr = 0x1c0;
          uint256 constant BasicOrder_order_counter_ptr = 0x1e0;
          uint256 constant BasicOrder_additionalRecipients_head_ptr = 0x240;
          uint256 constant BasicOrder_signature_ptr = 0x260;
          // Signature-related
          bytes32 constant EIP2098_allButHighestBitMask = (
              0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
          );
          bytes32 constant ECDSA_twentySeventhAndTwentyEighthBytesSet = (
              0x0000000000000000000000000000000000000000000000000000000101000000
          );
          uint256 constant ECDSA_MaxLength = 65;
          uint256 constant ECDSA_signature_s_offset = 0x40;
          uint256 constant ECDSA_signature_v_offset = 0x60;
          bytes32 constant EIP1271_isValidSignature_selector = (
              0x1626ba7e00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant EIP1271_isValidSignature_signatureHead_negativeOffset = 0x20;
          uint256 constant EIP1271_isValidSignature_digest_negativeOffset = 0x40;
          uint256 constant EIP1271_isValidSignature_selector_negativeOffset = 0x44;
          uint256 constant EIP1271_isValidSignature_calldata_baseLength = 0x64;
          uint256 constant EIP1271_isValidSignature_signature_head_offset = 0x40;
          // abi.encodeWithSignature("NoContract(address)")
          uint256 constant NoContract_error_signature = (
              0x5f15d67200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant NoContract_error_sig_ptr = 0x0;
          uint256 constant NoContract_error_token_ptr = 0x4;
          uint256 constant NoContract_error_length = 0x24; // 4 + 32 == 36
          uint256 constant EIP_712_PREFIX = (
              0x1901000000000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ExtraGasBuffer = 0x20;
          uint256 constant CostPerWord = 3;
          uint256 constant MemoryExpansionCoefficient = 0x200; // 512
          uint256 constant Create2AddressDerivation_ptr = 0x0b;
          uint256 constant Create2AddressDerivation_length = 0x55;
          uint256 constant MaskOverByteTwelve = (
              0x0000000000000000000000ff0000000000000000000000000000000000000000
          );
          uint256 constant MaskOverLastTwentyBytes = (
              0x000000000000000000000000ffffffffffffffffffffffffffffffffffffffff
          );
          uint256 constant MaskOverFirstFourBytes = (
              0xffffffff00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant Conduit_execute_signature = (
              0x4ce34aa200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant MaxUint8 = 0xff;
          uint256 constant MaxUint120 = 0xffffffffffffffffffffffffffffff;
          uint256 constant Conduit_execute_ConduitTransfer_ptr = 0x20;
          uint256 constant Conduit_execute_ConduitTransfer_length = 0x01;
          uint256 constant Conduit_execute_ConduitTransfer_offset_ptr = 0x04;
          uint256 constant Conduit_execute_ConduitTransfer_length_ptr = 0x24;
          uint256 constant Conduit_execute_transferItemType_ptr = 0x44;
          uint256 constant Conduit_execute_transferToken_ptr = 0x64;
          uint256 constant Conduit_execute_transferFrom_ptr = 0x84;
          uint256 constant Conduit_execute_transferTo_ptr = 0xa4;
          uint256 constant Conduit_execute_transferIdentifier_ptr = 0xc4;
          uint256 constant Conduit_execute_transferAmount_ptr = 0xe4;
          uint256 constant OneConduitExecute_size = 0x104;
          // Sentinel value to indicate that the conduit accumulator is not armed.
          uint256 constant AccumulatorDisarmed = 0x20;
          uint256 constant AccumulatorArmed = 0x40;
          uint256 constant Accumulator_conduitKey_ptr = 0x20;
          uint256 constant Accumulator_selector_ptr = 0x40;
          uint256 constant Accumulator_array_offset_ptr = 0x44;
          uint256 constant Accumulator_array_length_ptr = 0x64;
          uint256 constant Accumulator_itemSizeOffsetDifference = 0x3c;
          uint256 constant Accumulator_array_offset = 0x20;
          uint256 constant Conduit_transferItem_size = 0xc0;
          uint256 constant Conduit_transferItem_token_ptr = 0x20;
          uint256 constant Conduit_transferItem_from_ptr = 0x40;
          uint256 constant Conduit_transferItem_to_ptr = 0x60;
          uint256 constant Conduit_transferItem_identifier_ptr = 0x80;
          uint256 constant Conduit_transferItem_amount_ptr = 0xa0;
          // Declare constant for errors related to amount derivation.
          // error InexactFraction() @ AmountDerivationErrors.sol
          uint256 constant InexactFraction_error_signature = (
              0xc63cf08900000000000000000000000000000000000000000000000000000000
          );
          uint256 constant InexactFraction_error_len = 0x04;
          // Declare constant for errors related to signature verification.
          uint256 constant Ecrecover_precompile = 1;
          uint256 constant Ecrecover_args_size = 0x80;
          uint256 constant Signature_lower_v = 27;
          // error BadSignatureV(uint8) @ SignatureVerificationErrors.sol
          uint256 constant BadSignatureV_error_signature = (
              0x1f003d0a00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant BadSignatureV_error_offset = 0x04;
          uint256 constant BadSignatureV_error_length = 0x24;
          // error InvalidSigner() @ SignatureVerificationErrors.sol
          uint256 constant InvalidSigner_error_signature = (
              0x815e1d6400000000000000000000000000000000000000000000000000000000
          );
          uint256 constant InvalidSigner_error_length = 0x04;
          // error InvalidSignature() @ SignatureVerificationErrors.sol
          uint256 constant InvalidSignature_error_signature = (
              0x8baa579f00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant InvalidSignature_error_length = 0x04;
          // error BadContractSignature() @ SignatureVerificationErrors.sol
          uint256 constant BadContractSignature_error_signature = (
              0x4f7fb80d00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant BadContractSignature_error_length = 0x04;
          uint256 constant NumBitsAfterSelector = 0xe0;
          // 69 is the lowest modulus for which the remainder
          // of every selector other than the two match functions
          // is greater than those of the match functions.
          uint256 constant NonMatchSelector_MagicModulus = 69;
          // Of the two match function selectors, the highest
          // remainder modulo 69 is 29.
          uint256 constant NonMatchSelector_MagicRemainder = 0x1d;
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { OrderParameters } from "./ConsiderationStructs.sol";
          import { GettersAndDerivers } from "./GettersAndDerivers.sol";
          // prettier-ignore
          import {
              TokenTransferrerErrors
          } from "../interfaces/TokenTransferrerErrors.sol";
          import { CounterManager } from "./CounterManager.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title Assertions
           * @author 0age
           * @notice Assertions contains logic for making various assertions that do not
           *         fit neatly within a dedicated semantic scope.
           */
          contract Assertions is
              GettersAndDerivers,
              CounterManager,
              TokenTransferrerErrors
          {
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController)
                  GettersAndDerivers(conduitController)
              {}
              /**
               * @dev Internal view function to ensure that the supplied consideration
               *      array length on a given set of order parameters is not less than the
               *      original consideration array length for that order and to retrieve
               *      the current counter for a given order's offerer and zone and use it
               *      to derive the order hash.
               *
               * @param orderParameters The parameters of the order to hash.
               *
               * @return The hash.
               */
              function _assertConsiderationLengthAndGetOrderHash(
                  OrderParameters memory orderParameters
              ) internal view returns (bytes32) {
                  // Ensure supplied consideration array length is not less than original.
                  _assertConsiderationLengthIsNotLessThanOriginalConsiderationLength(
                      orderParameters.consideration.length,
                      orderParameters.totalOriginalConsiderationItems
                  );
                  // Derive and return order hash using current counter for the offerer.
                  return
                      _deriveOrderHash(
                          orderParameters,
                          _getCounter(orderParameters.offerer)
                      );
              }
              /**
               * @dev Internal pure function to ensure that the supplied consideration
               *      array length for an order to be fulfilled is not less than the
               *      original consideration array length for that order.
               *
               * @param suppliedConsiderationItemTotal The number of consideration items
               *                                       supplied when fulfilling the order.
               * @param originalConsiderationItemTotal The number of consideration items
               *                                       supplied on initial order creation.
               */
              function _assertConsiderationLengthIsNotLessThanOriginalConsiderationLength(
                  uint256 suppliedConsiderationItemTotal,
                  uint256 originalConsiderationItemTotal
              ) internal pure {
                  // Ensure supplied consideration array length is not less than original.
                  if (suppliedConsiderationItemTotal < originalConsiderationItemTotal) {
                      revert MissingOriginalConsiderationItems();
                  }
              }
              /**
               * @dev Internal pure function to ensure that a given item amount is not
               *      zero.
               *
               * @param amount The amount to check.
               */
              function _assertNonZeroAmount(uint256 amount) internal pure {
                  // Revert if the supplied amount is equal to zero.
                  if (amount == 0) {
                      revert MissingItemAmount();
                  }
              }
              /**
               * @dev Internal pure function to validate calldata offsets for dynamic
               *      types in BasicOrderParameters and other parameters. This ensures
               *      that functions using the calldata object normally will be using the
               *      same data as the assembly functions and that values that are bound
               *      to a given range are within that range. Note that no parameters are
               *      supplied as all basic order functions use the same calldata
               *      encoding.
               */
              function _assertValidBasicOrderParameters() internal pure {
                  // Declare a boolean designating basic order parameter offset validity.
                  bool validOffsets;
                  // Utilize assembly in order to read offset data directly from calldata.
                  assembly {
                      /*
                       * Checks:
                       * 1. Order parameters struct offset == 0x20
                       * 2. Additional recipients arr offset == 0x240
                       * 3. Signature offset == 0x260 + (recipients.length * 0x40)
                       * 4. BasicOrderType between 0 and 23 (i.e. < 24)
                       */
                      validOffsets := and(
                          // Order parameters at calldata 0x04 must have offset of 0x20.
                          eq(
                              calldataload(BasicOrder_parameters_cdPtr),
                              BasicOrder_parameters_ptr
                          ),
                          // Additional recipients at cd 0x224 must have offset of 0x240.
                          eq(
                              calldataload(BasicOrder_additionalRecipients_head_cdPtr),
                              BasicOrder_additionalRecipients_head_ptr
                          )
                      )
                      validOffsets := and(
                          validOffsets,
                          eq(
                              // Load signature offset from calldata 0x244.
                              calldataload(BasicOrder_signature_cdPtr),
                              // Derive expected offset as start of recipients + len * 64.
                              add(
                                  BasicOrder_signature_ptr,
                                  mul(
                                      // Additional recipients length at calldata 0x264.
                                      calldataload(
                                          BasicOrder_additionalRecipients_length_cdPtr
                                      ),
                                      // Each additional recipient has a length of 0x40.
                                      AdditionalRecipients_size
                                  )
                              )
                          )
                      )
                      validOffsets := and(
                          validOffsets,
                          lt(
                              // BasicOrderType parameter at calldata offset 0x124.
                              calldataload(BasicOrder_basicOrderType_cdPtr),
                              // Value should be less than 24.
                              BasicOrder_basicOrderType_range
                          )
                      )
                  }
                  // Revert with an error if basic order parameter offsets are invalid.
                  if (!validOffsets) {
                      revert InvalidBasicOrderParameterEncoding();
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { EIP1271Interface } from "../interfaces/EIP1271Interface.sol";
          // prettier-ignore
          import {
              SignatureVerificationErrors
          } from "../interfaces/SignatureVerificationErrors.sol";
          import { LowLevelHelpers } from "./LowLevelHelpers.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title SignatureVerification
           * @author 0age
           * @notice SignatureVerification contains logic for verifying signatures.
           */
          contract SignatureVerification is SignatureVerificationErrors, LowLevelHelpers {
              /**
               * @dev Internal view function to verify the signature of an order. An
               *      ERC-1271 fallback will be attempted if either the signature length
               *      is not 64 or 65 bytes or if the recovered signer does not match the
               *      supplied signer.
               *
               * @param signer    The signer for the order.
               * @param digest    The digest to verify the signature against.
               * @param signature A signature from the signer indicating that the order
               *                  has been approved.
               */
              function _assertValidSignature(
                  address signer,
                  bytes32 digest,
                  bytes memory signature
              ) internal view {
                  // Declare value for ecrecover equality or 1271 call success status.
                  bool success;
                  // Utilize assembly to perform optimized signature verification check.
                  assembly {
                      // Ensure that first word of scratch space is empty.
                      mstore(0, 0)
                      // Declare value for v signature parameter.
                      let v
                      // Get the length of the signature.
                      let signatureLength := mload(signature)
                      // Get the pointer to the value preceding the signature length.
                      // This will be used for temporary memory overrides - either the
                      // signature head for isValidSignature or the digest for ecrecover.
                      let wordBeforeSignaturePtr := sub(signature, OneWord)
                      // Cache the current value behind the signature to restore it later.
                      let cachedWordBeforeSignature := mload(wordBeforeSignaturePtr)
                      // Declare lenDiff + recoveredSigner scope to manage stack pressure.
                      {
                          // Take the difference between the max ECDSA signature length
                          // and the actual signature length. Overflow desired for any
                          // values > 65. If the diff is not 0 or 1, it is not a valid
                          // ECDSA signature - move on to EIP1271 check.
                          let lenDiff := sub(ECDSA_MaxLength, signatureLength)
                          // Declare variable for recovered signer.
                          let recoveredSigner
                          // If diff is 0 or 1, it may be an ECDSA signature.
                          // Try to recover signer.
                          if iszero(gt(lenDiff, 1)) {
                              // Read the signature `s` value.
                              let originalSignatureS := mload(
                                  add(signature, ECDSA_signature_s_offset)
                              )
                              // Read the first byte of the word after `s`. If the
                              // signature is 65 bytes, this will be the real `v` value.
                              // If not, it will need to be modified - doing it this way
                              // saves an extra condition.
                              v := byte(
                                  0,
                                  mload(add(signature, ECDSA_signature_v_offset))
                              )
                              // If lenDiff is 1, parse 64-byte signature as ECDSA.
                              if lenDiff {
                                  // Extract yParity from highest bit of vs and add 27 to
                                  // get v.
                                  v := add(
                                      shr(MaxUint8, originalSignatureS),
                                      Signature_lower_v
                                  )
                                  // Extract canonical s from vs, all but the highest bit.
                                  // Temporarily overwrite the original `s` value in the
                                  // signature.
                                  mstore(
                                      add(signature, ECDSA_signature_s_offset),
                                      and(
                                          originalSignatureS,
                                          EIP2098_allButHighestBitMask
                                      )
                                  )
                              }
                              // Temporarily overwrite the signature length with `v` to
                              // conform to the expected input for ecrecover.
                              mstore(signature, v)
                              // Temporarily overwrite the word before the length with
                              // `digest` to conform to the expected input for ecrecover.
                              mstore(wordBeforeSignaturePtr, digest)
                              // Attempt to recover the signer for the given signature. Do
                              // not check the call status as ecrecover will return a null
                              // address if the signature is invalid.
                              pop(
                                  staticcall(
                                      gas(),
                                      Ecrecover_precompile, // Call ecrecover precompile.
                                      wordBeforeSignaturePtr, // Use data memory location.
                                      Ecrecover_args_size, // Size of digest, v, r, and s.
                                      0, // Write result to scratch space.
                                      OneWord // Provide size of returned result.
                                  )
                              )
                              // Restore cached word before signature.
                              mstore(wordBeforeSignaturePtr, cachedWordBeforeSignature)
                              // Restore cached signature length.
                              mstore(signature, signatureLength)
                              // Restore cached signature `s` value.
                              mstore(
                                  add(signature, ECDSA_signature_s_offset),
                                  originalSignatureS
                              )
                              // Read the recovered signer from the buffer given as return
                              // space for ecrecover.
                              recoveredSigner := mload(0)
                          }
                          // Set success to true if the signature provided was a valid
                          // ECDSA signature and the signer is not the null address. Use
                          // gt instead of direct as success is used outside of assembly.
                          success := and(eq(signer, recoveredSigner), gt(signer, 0))
                      }
                      // If the signature was not verified with ecrecover, try EIP1271.
                      if iszero(success) {
                          // Temporarily overwrite the word before the signature length
                          // and use it as the head of the signature input to
                          // `isValidSignature`, which has a value of 64.
                          mstore(
                              wordBeforeSignaturePtr,
                              EIP1271_isValidSignature_signature_head_offset
                          )
                          // Get pointer to use for the selector of `isValidSignature`.
                          let selectorPtr := sub(
                              signature,
                              EIP1271_isValidSignature_selector_negativeOffset
                          )
                          // Cache the value currently stored at the selector pointer.
                          let cachedWordOverwrittenBySelector := mload(selectorPtr)
                          // Get pointer to use for `digest` input to `isValidSignature`.
                          let digestPtr := sub(
                              signature,
                              EIP1271_isValidSignature_digest_negativeOffset
                          )
                          // Cache the value currently stored at the digest pointer.
                          let cachedWordOverwrittenByDigest := mload(digestPtr)
                          // Write the selector first, since it overlaps the digest.
                          mstore(selectorPtr, EIP1271_isValidSignature_selector)
                          // Next, write the digest.
                          mstore(digestPtr, digest)
                          // Call signer with `isValidSignature` to validate signature.
                          success := staticcall(
                              gas(),
                              signer,
                              selectorPtr,
                              add(
                                  signatureLength,
                                  EIP1271_isValidSignature_calldata_baseLength
                              ),
                              0,
                              OneWord
                          )
                          // Determine if the signature is valid on successful calls.
                          if success {
                              // If first word of scratch space does not contain EIP-1271
                              // signature selector, revert.
                              if iszero(eq(mload(0), EIP1271_isValidSignature_selector)) {
                                  // Revert with bad 1271 signature if signer has code.
                                  if extcodesize(signer) {
                                      // Bad contract signature.
                                      mstore(0, BadContractSignature_error_signature)
                                      revert(0, BadContractSignature_error_length)
                                  }
                                  // Check if signature length was invalid.
                                  if gt(sub(ECDSA_MaxLength, signatureLength), 1) {
                                      // Revert with generic invalid signature error.
                                      mstore(0, InvalidSignature_error_signature)
                                      revert(0, InvalidSignature_error_length)
                                  }
                                  // Check if v was invalid.
                                  if iszero(
                                      byte(v, ECDSA_twentySeventhAndTwentyEighthBytesSet)
                                  ) {
                                      // Revert with invalid v value.
                                      mstore(0, BadSignatureV_error_signature)
                                      mstore(BadSignatureV_error_offset, v)
                                      revert(0, BadSignatureV_error_length)
                                  }
                                  // Revert with generic invalid signer error message.
                                  mstore(0, InvalidSigner_error_signature)
                                  revert(0, InvalidSigner_error_length)
                              }
                          }
                          // Restore the cached values overwritten by selector, digest and
                          // signature head.
                          mstore(wordBeforeSignaturePtr, cachedWordBeforeSignature)
                          mstore(selectorPtr, cachedWordOverwrittenBySelector)
                          mstore(digestPtr, cachedWordOverwrittenByDigest)
                      }
                  }
                  // If the call failed...
                  if (!success) {
                      // Revert and pass reason along if one was returned.
                      _revertWithReasonIfOneIsReturned();
                      // Otherwise, revert with error indicating bad contract signature.
                      assembly {
                          mstore(0, BadContractSignature_error_signature)
                          revert(0, BadContractSignature_error_length)
                      }
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { OrderParameters } from "./ConsiderationStructs.sol";
          import { ConsiderationBase } from "./ConsiderationBase.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title GettersAndDerivers
           * @author 0age
           * @notice ConsiderationInternal contains pure and internal view functions
           *         related to getting or deriving various values.
           */
          contract GettersAndDerivers is ConsiderationBase {
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController)
                  ConsiderationBase(conduitController)
              {}
              /**
               * @dev Internal view function to derive the order hash for a given order.
               *      Note that only the original consideration items are included in the
               *      order hash, as additional consideration items may be supplied by the
               *      caller.
               *
               * @param orderParameters The parameters of the order to hash.
               * @param counter           The counter of the order to hash.
               *
               * @return orderHash The hash.
               */
              function _deriveOrderHash(
                  OrderParameters memory orderParameters,
                  uint256 counter
              ) internal view returns (bytes32 orderHash) {
                  // Get length of original consideration array and place it on the stack.
                  uint256 originalConsiderationLength = (
                      orderParameters.totalOriginalConsiderationItems
                  );
                  /*
                   * Memory layout for an array of structs (dynamic or not) is similar
                   * to ABI encoding of dynamic types, with a head segment followed by
                   * a data segment. The main difference is that the head of an element
                   * is a memory pointer rather than an offset.
                   */
                  // Declare a variable for the derived hash of the offer array.
                  bytes32 offerHash;
                  // Read offer item EIP-712 typehash from runtime code & place on stack.
                  bytes32 typeHash = _OFFER_ITEM_TYPEHASH;
                  // Utilize assembly so that memory regions can be reused across hashes.
                  assembly {
                      // Retrieve the free memory pointer and place on the stack.
                      let hashArrPtr := mload(FreeMemoryPointerSlot)
                      // Get the pointer to the offers array.
                      let offerArrPtr := mload(
                          add(orderParameters, OrderParameters_offer_head_offset)
                      )
                      // Load the length.
                      let offerLength := mload(offerArrPtr)
                      // Set the pointer to the first offer's head.
                      offerArrPtr := add(offerArrPtr, OneWord)
                      // Iterate over the offer items.
                      // prettier-ignore
                      for { let i := 0 } lt(i, offerLength) {
                          i := add(i, 1)
                      } {
                          // Read the pointer to the offer data and subtract one word
                          // to get typeHash pointer.
                          let ptr := sub(mload(offerArrPtr), OneWord)
                          // Read the current value before the offer data.
                          let value := mload(ptr)
                          // Write the type hash to the previous word.
                          mstore(ptr, typeHash)
                          // Take the EIP712 hash and store it in the hash array.
                          mstore(hashArrPtr, keccak256(ptr, EIP712_OfferItem_size))
                          // Restore the previous word.
                          mstore(ptr, value)
                          // Increment the array pointers by one word.
                          offerArrPtr := add(offerArrPtr, OneWord)
                          hashArrPtr := add(hashArrPtr, OneWord)
                      }
                      // Derive the offer hash using the hashes of each item.
                      offerHash := keccak256(
                          mload(FreeMemoryPointerSlot),
                          mul(offerLength, OneWord)
                      )
                  }
                  // Declare a variable for the derived hash of the consideration array.
                  bytes32 considerationHash;
                  // Read consideration item typehash from runtime code & place on stack.
                  typeHash = _CONSIDERATION_ITEM_TYPEHASH;
                  // Utilize assembly so that memory regions can be reused across hashes.
                  assembly {
                      // Retrieve the free memory pointer and place on the stack.
                      let hashArrPtr := mload(FreeMemoryPointerSlot)
                      // Get the pointer to the consideration array.
                      let considerationArrPtr := add(
                          mload(
                              add(
                                  orderParameters,
                                  OrderParameters_consideration_head_offset
                              )
                          ),
                          OneWord
                      )
                      // Iterate over the consideration items (not including tips).
                      // prettier-ignore
                      for { let i := 0 } lt(i, originalConsiderationLength) {
                          i := add(i, 1)
                      } {
                          // Read the pointer to the consideration data and subtract one
                          // word to get typeHash pointer.
                          let ptr := sub(mload(considerationArrPtr), OneWord)
                          // Read the current value before the consideration data.
                          let value := mload(ptr)
                          // Write the type hash to the previous word.
                          mstore(ptr, typeHash)
                          // Take the EIP712 hash and store it in the hash array.
                          mstore(
                              hashArrPtr,
                              keccak256(ptr, EIP712_ConsiderationItem_size)
                          )
                          // Restore the previous word.
                          mstore(ptr, value)
                          // Increment the array pointers by one word.
                          considerationArrPtr := add(considerationArrPtr, OneWord)
                          hashArrPtr := add(hashArrPtr, OneWord)
                      }
                      // Derive the consideration hash using the hashes of each item.
                      considerationHash := keccak256(
                          mload(FreeMemoryPointerSlot),
                          mul(originalConsiderationLength, OneWord)
                      )
                  }
                  // Read order item EIP-712 typehash from runtime code & place on stack.
                  typeHash = _ORDER_TYPEHASH;
                  // Utilize assembly to access derived hashes & other arguments directly.
                  assembly {
                      // Retrieve pointer to the region located just behind parameters.
                      let typeHashPtr := sub(orderParameters, OneWord)
                      // Store the value at that pointer location to restore later.
                      let previousValue := mload(typeHashPtr)
                      // Store the order item EIP-712 typehash at the typehash location.
                      mstore(typeHashPtr, typeHash)
                      // Retrieve the pointer for the offer array head.
                      let offerHeadPtr := add(
                          orderParameters,
                          OrderParameters_offer_head_offset
                      )
                      // Retrieve the data pointer referenced by the offer head.
                      let offerDataPtr := mload(offerHeadPtr)
                      // Store the offer hash at the retrieved memory location.
                      mstore(offerHeadPtr, offerHash)
                      // Retrieve the pointer for the consideration array head.
                      let considerationHeadPtr := add(
                          orderParameters,
                          OrderParameters_consideration_head_offset
                      )
                      // Retrieve the data pointer referenced by the consideration head.
                      let considerationDataPtr := mload(considerationHeadPtr)
                      // Store the consideration hash at the retrieved memory location.
                      mstore(considerationHeadPtr, considerationHash)
                      // Retrieve the pointer for the counter.
                      let counterPtr := add(
                          orderParameters,
                          OrderParameters_counter_offset
                      )
                      // Store the counter at the retrieved memory location.
                      mstore(counterPtr, counter)
                      // Derive the order hash using the full range of order parameters.
                      orderHash := keccak256(typeHashPtr, EIP712_Order_size)
                      // Restore the value previously held at typehash pointer location.
                      mstore(typeHashPtr, previousValue)
                      // Restore offer data pointer at the offer head pointer location.
                      mstore(offerHeadPtr, offerDataPtr)
                      // Restore consideration data pointer at the consideration head ptr.
                      mstore(considerationHeadPtr, considerationDataPtr)
                      // Restore consideration item length at the counter pointer.
                      mstore(counterPtr, originalConsiderationLength)
                  }
              }
              /**
               * @dev Internal view function to derive the address of a given conduit
               *      using a corresponding conduit key.
               *
               * @param conduitKey A bytes32 value indicating what corresponding conduit,
               *                   if any, to source token approvals from. This value is
               *                   the "salt" parameter supplied by the deployer (i.e. the
               *                   conduit controller) when deploying the given conduit.
               *
               * @return conduit The address of the conduit associated with the given
               *                 conduit key.
               */
              function _deriveConduit(bytes32 conduitKey)
                  internal
                  view
                  returns (address conduit)
              {
                  // Read conduit controller address from runtime and place on the stack.
                  address conduitController = address(_CONDUIT_CONTROLLER);
                  // Read conduit creation code hash from runtime and place on the stack.
                  bytes32 conduitCreationCodeHash = _CONDUIT_CREATION_CODE_HASH;
                  // Leverage scratch space to perform an efficient hash.
                  assembly {
                      // Retrieve the free memory pointer; it will be replaced afterwards.
                      let freeMemoryPointer := mload(FreeMemoryPointerSlot)
                      // Place the control character and the conduit controller in scratch
                      // space; note that eleven bytes at the beginning are left unused.
                      mstore(0, or(MaskOverByteTwelve, conduitController))
                      // Place the conduit key in the next region of scratch space.
                      mstore(OneWord, conduitKey)
                      // Place conduit creation code hash in free memory pointer location.
                      mstore(TwoWords, conduitCreationCodeHash)
                      // Derive conduit by hashing and applying a mask over last 20 bytes.
                      conduit := and(
                          // Hash the relevant region.
                          keccak256(
                              // The region starts at memory pointer 11.
                              Create2AddressDerivation_ptr,
                              // The region is 85 bytes long (1 + 20 + 32 + 32).
                              Create2AddressDerivation_length
                          ),
                          // The address equals the last twenty bytes of the hash.
                          MaskOverLastTwentyBytes
                      )
                      // Restore the free memory pointer.
                      mstore(FreeMemoryPointerSlot, freeMemoryPointer)
                  }
              }
              /**
               * @dev Internal view function to get the EIP-712 domain separator. If the
               *      chainId matches the chainId set on deployment, the cached domain
               *      separator will be returned; otherwise, it will be derived from
               *      scratch.
               *
               * @return The domain separator.
               */
              function _domainSeparator() internal view returns (bytes32) {
                  // prettier-ignore
                  return block.chainid == _CHAIN_ID
                      ? _DOMAIN_SEPARATOR
                      : _deriveDomainSeparator();
              }
              /**
               * @dev Internal view function to retrieve configuration information for
               *      this contract.
               *
               * @return version           The contract version.
               * @return domainSeparator   The domain separator for this contract.
               * @return conduitController The conduit Controller set for this contract.
               */
              function _information()
                  internal
                  view
                  returns (
                      string memory version,
                      bytes32 domainSeparator,
                      address conduitController
                  )
              {
                  // Derive the domain separator.
                  domainSeparator = _domainSeparator();
                  // Declare variable as immutables cannot be accessed within assembly.
                  conduitController = address(_CONDUIT_CONTROLLER);
                  // Allocate a string with the intended length.
                  version = new string(Version_length);
                  // Set the version as data on the newly allocated string.
                  assembly {
                      mstore(add(version, OneWord), shl(Version_shift, Version))
                  }
              }
              /**
               * @dev Internal pure function to efficiently derive an digest to sign for
               *      an order in accordance with EIP-712.
               *
               * @param domainSeparator The domain separator.
               * @param orderHash       The order hash.
               *
               * @return value The hash.
               */
              function _deriveEIP712Digest(bytes32 domainSeparator, bytes32 orderHash)
                  internal
                  pure
                  returns (bytes32 value)
              {
                  // Leverage scratch space to perform an efficient hash.
                  assembly {
                      // Place the EIP-712 prefix at the start of scratch space.
                      mstore(0, EIP_712_PREFIX)
                      // Place the domain separator in the next region of scratch space.
                      mstore(EIP712_DomainSeparator_offset, domainSeparator)
                      // Place the order hash in scratch space, spilling into the first
                      // two bytes of the free memory pointer — this should never be set
                      // as memory cannot be expanded to that size, and will be zeroed out
                      // after the hash is performed.
                      mstore(EIP712_OrderHash_offset, orderHash)
                      // Hash the relevant region (65 bytes).
                      value := keccak256(0, EIP712_DigestPayload_size)
                      // Clear out the dirtied bits in the memory pointer.
                      mstore(EIP712_OrderHash_offset, 0)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          // prettier-ignore
          import {
              ConsiderationEventsAndErrors
          } from "../interfaces/ConsiderationEventsAndErrors.sol";
          import { ReentrancyGuard } from "./ReentrancyGuard.sol";
          /**
           * @title CounterManager
           * @author 0age
           * @notice CounterManager contains a storage mapping and related functionality
           *         for retrieving and incrementing a per-offerer counter.
           */
          contract CounterManager is ConsiderationEventsAndErrors, ReentrancyGuard {
              // Only orders signed using an offerer's current counter are fulfillable.
              mapping(address => uint256) private _counters;
              /**
               * @dev Internal function to cancel all orders from a given offerer with a
               *      given zone in bulk by incrementing a counter. Note that only the
               *      offerer may increment the counter.
               *
               * @return newCounter The new counter.
               */
              function _incrementCounter() internal returns (uint256 newCounter) {
                  // Ensure that the reentrancy guard is not currently set.
                  _assertNonReentrant();
                  // Skip overflow check as counter cannot be incremented that far.
                  unchecked {
                      // Increment current counter for the supplied offerer.
                      newCounter = ++_counters[msg.sender];
                  }
                  // Emit an event containing the new counter.
                  emit CounterIncremented(newCounter, msg.sender);
              }
              /**
               * @dev Internal view function to retrieve the current counter for a given
               *      offerer.
               *
               * @param offerer The offerer in question.
               *
               * @return currentCounter The current counter.
               */
              function _getCounter(address offerer)
                  internal
                  view
                  returns (uint256 currentCounter)
              {
                  // Return the counter for the supplied offerer.
                  currentCounter = _counters[offerer];
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          // prettier-ignore
          import {
              ConduitControllerInterface
          } from "../interfaces/ConduitControllerInterface.sol";
          // prettier-ignore
          import {
              ConsiderationEventsAndErrors
          } from "../interfaces/ConsiderationEventsAndErrors.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title ConsiderationBase
           * @author 0age
           * @notice ConsiderationBase contains immutable constants and constructor logic.
           */
          contract ConsiderationBase is ConsiderationEventsAndErrors {
              // Precompute hashes, original chainId, and domain separator on deployment.
              bytes32 internal immutable _NAME_HASH;
              bytes32 internal immutable _VERSION_HASH;
              bytes32 internal immutable _EIP_712_DOMAIN_TYPEHASH;
              bytes32 internal immutable _OFFER_ITEM_TYPEHASH;
              bytes32 internal immutable _CONSIDERATION_ITEM_TYPEHASH;
              bytes32 internal immutable _ORDER_TYPEHASH;
              uint256 internal immutable _CHAIN_ID;
              bytes32 internal immutable _DOMAIN_SEPARATOR;
              // Allow for interaction with the conduit controller.
              ConduitControllerInterface internal immutable _CONDUIT_CONTROLLER;
              // Cache the conduit creation code hash used by the conduit controller.
              bytes32 internal immutable _CONDUIT_CREATION_CODE_HASH;
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) {
                  // Derive name and version hashes alongside required EIP-712 typehashes.
                  (
                      _NAME_HASH,
                      _VERSION_HASH,
                      _EIP_712_DOMAIN_TYPEHASH,
                      _OFFER_ITEM_TYPEHASH,
                      _CONSIDERATION_ITEM_TYPEHASH,
                      _ORDER_TYPEHASH
                  ) = _deriveTypehashes();
                  // Store the current chainId and derive the current domain separator.
                  _CHAIN_ID = block.chainid;
                  _DOMAIN_SEPARATOR = _deriveDomainSeparator();
                  // Set the supplied conduit controller.
                  _CONDUIT_CONTROLLER = ConduitControllerInterface(conduitController);
                  // Retrieve the conduit creation code hash from the supplied controller.
                  (_CONDUIT_CREATION_CODE_HASH, ) = (
                      _CONDUIT_CONTROLLER.getConduitCodeHashes()
                  );
              }
              /**
               * @dev Internal view function to derive the EIP-712 domain separator.
               *
               * @return The derived domain separator.
               */
              function _deriveDomainSeparator() internal view returns (bytes32) {
                  // prettier-ignore
                  return keccak256(
                      abi.encode(
                          _EIP_712_DOMAIN_TYPEHASH,
                          _NAME_HASH,
                          _VERSION_HASH,
                          block.chainid,
                          address(this)
                      )
                  );
              }
              /**
               * @dev Internal pure function to retrieve the default name of this
               *      contract and return.
               *
               * @return The name of this contract.
               */
              function _name() internal pure virtual returns (string memory) {
                  // Return the name of the contract.
                  assembly {
                      // First element is the offset for the returned string. Offset the
                      // value in memory by one word so that the free memory pointer will
                      // be overwritten by the next write.
                      mstore(OneWord, OneWord)
                      // Name is right padded, so it touches the length which is left
                      // padded. This enables writing both values at once. The free memory
                      // pointer will be overwritten in the process.
                      mstore(NameLengthPtr, NameWithLength)
                      // Standard ABI encoding pads returned data to the nearest word. Use
                      // the already empty zero slot memory region for this purpose and
                      // return the final name string, offset by the original single word.
                      return(OneWord, ThreeWords)
                  }
              }
              /**
               * @dev Internal pure function to retrieve the default name of this contract
               *      as a string that can be used internally.
               *
               * @return The name of this contract.
               */
              function _nameString() internal pure virtual returns (string memory) {
                  // Return the name of the contract.
                  return "Consideration";
              }
              /**
               * @dev Internal pure function to derive required EIP-712 typehashes and
               *      other hashes during contract creation.
               *
               * @return nameHash                  The hash of the name of the contract.
               * @return versionHash               The hash of the version string of the
               *                                   contract.
               * @return eip712DomainTypehash      The primary EIP-712 domain typehash.
               * @return offerItemTypehash         The EIP-712 typehash for OfferItem
               *                                   types.
               * @return considerationItemTypehash The EIP-712 typehash for
               *                                   ConsiderationItem types.
               * @return orderTypehash             The EIP-712 typehash for Order types.
               */
              function _deriveTypehashes()
                  internal
                  pure
                  returns (
                      bytes32 nameHash,
                      bytes32 versionHash,
                      bytes32 eip712DomainTypehash,
                      bytes32 offerItemTypehash,
                      bytes32 considerationItemTypehash,
                      bytes32 orderTypehash
                  )
              {
                  // Derive hash of the name of the contract.
                  nameHash = keccak256(bytes(_nameString()));
                  // Derive hash of the version string of the contract.
                  versionHash = keccak256(bytes("1.1"));
                  // Construct the OfferItem type string.
                  // prettier-ignore
                  bytes memory offerItemTypeString = abi.encodePacked(
                      "OfferItem(",
                          "uint8 itemType,",
                          "address token,",
                          "uint256 identifierOrCriteria,",
                          "uint256 startAmount,",
                          "uint256 endAmount",
                      ")"
                  );
                  // Construct the ConsiderationItem type string.
                  // prettier-ignore
                  bytes memory considerationItemTypeString = abi.encodePacked(
                      "ConsiderationItem(",
                          "uint8 itemType,",
                          "address token,",
                          "uint256 identifierOrCriteria,",
                          "uint256 startAmount,",
                          "uint256 endAmount,",
                          "address recipient",
                      ")"
                  );
                  // Construct the OrderComponents type string, not including the above.
                  // prettier-ignore
                  bytes memory orderComponentsPartialTypeString = abi.encodePacked(
                      "OrderComponents(",
                          "address offerer,",
                          "address zone,",
                          "OfferItem[] offer,",
                          "ConsiderationItem[] consideration,",
                          "uint8 orderType,",
                          "uint256 startTime,",
                          "uint256 endTime,",
                          "bytes32 zoneHash,",
                          "uint256 salt,",
                          "bytes32 conduitKey,",
                          "uint256 counter",
                      ")"
                  );
                  // Construct the primary EIP-712 domain type string.
                  // prettier-ignore
                  eip712DomainTypehash = keccak256(
                      abi.encodePacked(
                          "EIP712Domain(",
                              "string name,",
                              "string version,",
                              "uint256 chainId,",
                              "address verifyingContract",
                          ")"
                      )
                  );
                  // Derive the OfferItem type hash using the corresponding type string.
                  offerItemTypehash = keccak256(offerItemTypeString);
                  // Derive ConsiderationItem type hash using corresponding type string.
                  considerationItemTypehash = keccak256(considerationItemTypeString);
                  // Derive OrderItem type hash via combination of relevant type strings.
                  orderTypehash = keccak256(
                      abi.encodePacked(
                          orderComponentsPartialTypeString,
                          considerationItemTypeString,
                          offerItemTypeString
                      )
                  );
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { SpentItem, ReceivedItem } from "../lib/ConsiderationStructs.sol";
          /**
           * @title ConsiderationEventsAndErrors
           * @author 0age
           * @notice ConsiderationEventsAndErrors contains all events and errors.
           */
          interface ConsiderationEventsAndErrors {
              /**
               * @dev Emit an event whenever an order is successfully fulfilled.
               *
               * @param orderHash     The hash of the fulfilled order.
               * @param offerer       The offerer of the fulfilled order.
               * @param zone          The zone of the fulfilled order.
               * @param recipient     The recipient of each spent item on the fulfilled
               *                      order, or the null address if there is no specific
               *                      fulfiller (i.e. the order is part of a group of
               *                      orders). Defaults to the caller unless explicitly
               *                      specified otherwise by the fulfiller.
               * @param offer         The offer items spent as part of the order.
               * @param consideration The consideration items received as part of the
               *                      order along with the recipients of each item.
               */
              event OrderFulfilled(
                  bytes32 orderHash,
                  address indexed offerer,
                  address indexed zone,
                  address recipient,
                  SpentItem[] offer,
                  ReceivedItem[] consideration
              );
              /**
               * @dev Emit an event whenever an order is successfully cancelled.
               *
               * @param orderHash The hash of the cancelled order.
               * @param offerer   The offerer of the cancelled order.
               * @param zone      The zone of the cancelled order.
               */
              event OrderCancelled(
                  bytes32 orderHash,
                  address indexed offerer,
                  address indexed zone
              );
              /**
               * @dev Emit an event whenever an order is explicitly validated. Note that
               *      this event will not be emitted on partial fills even though they do
               *      validate the order as part of partial fulfillment.
               *
               * @param orderHash The hash of the validated order.
               * @param offerer   The offerer of the validated order.
               * @param zone      The zone of the validated order.
               */
              event OrderValidated(
                  bytes32 orderHash,
                  address indexed offerer,
                  address indexed zone
              );
              /**
               * @dev Emit an event whenever a counter for a given offerer is incremented.
               *
               * @param newCounter The new counter for the offerer.
               * @param offerer  The offerer in question.
               */
              event CounterIncremented(uint256 newCounter, address indexed offerer);
              /**
               * @dev Revert with an error when attempting to fill an order that has
               *      already been fully filled.
               *
               * @param orderHash The order hash on which a fill was attempted.
               */
              error OrderAlreadyFilled(bytes32 orderHash);
              /**
               * @dev Revert with an error when attempting to fill an order outside the
               *      specified start time and end time.
               */
              error InvalidTime();
              /**
               * @dev Revert with an error when attempting to fill an order referencing an
               *      invalid conduit (i.e. one that has not been deployed).
               */
              error InvalidConduit(bytes32 conduitKey, address conduit);
              /**
               * @dev Revert with an error when an order is supplied for fulfillment with
               *      a consideration array that is shorter than the original array.
               */
              error MissingOriginalConsiderationItems();
              /**
               * @dev Revert with an error when a call to a conduit fails with revert data
               *      that is too expensive to return.
               */
              error InvalidCallToConduit(address conduit);
              /**
               * @dev Revert with an error if a consideration amount has not been fully
               *      zeroed out after applying all fulfillments.
               *
               * @param orderIndex         The index of the order with the consideration
               *                           item with a shortfall.
               * @param considerationIndex The index of the consideration item on the
               *                           order.
               * @param shortfallAmount    The unfulfilled consideration amount.
               */
              error ConsiderationNotMet(
                  uint256 orderIndex,
                  uint256 considerationIndex,
                  uint256 shortfallAmount
              );
              /**
               * @dev Revert with an error when insufficient ether is supplied as part of
               *      msg.value when fulfilling orders.
               */
              error InsufficientEtherSupplied();
              /**
               * @dev Revert with an error when an ether transfer reverts.
               */
              error EtherTransferGenericFailure(address account, uint256 amount);
              /**
               * @dev Revert with an error when a partial fill is attempted on an order
               *      that does not specify partial fill support in its order type.
               */
              error PartialFillsNotEnabledForOrder();
              /**
               * @dev Revert with an error when attempting to fill an order that has been
               *      cancelled.
               *
               * @param orderHash The hash of the cancelled order.
               */
              error OrderIsCancelled(bytes32 orderHash);
              /**
               * @dev Revert with an error when attempting to fill a basic order that has
               *      been partially filled.
               *
               * @param orderHash The hash of the partially used order.
               */
              error OrderPartiallyFilled(bytes32 orderHash);
              /**
               * @dev Revert with an error when attempting to cancel an order as a caller
               *      other than the indicated offerer or zone.
               */
              error InvalidCanceller();
              /**
               * @dev Revert with an error when supplying a fraction with a value of zero
               *      for the numerator or denominator, or one where the numerator exceeds
               *      the denominator.
               */
              error BadFraction();
              /**
               * @dev Revert with an error when a caller attempts to supply callvalue to a
               *      non-payable basic order route or does not supply any callvalue to a
               *      payable basic order route.
               */
              error InvalidMsgValue(uint256 value);
              /**
               * @dev Revert with an error when attempting to fill a basic order using
               *      calldata not produced by default ABI encoding.
               */
              error InvalidBasicOrderParameterEncoding();
              /**
               * @dev Revert with an error when attempting to fulfill any number of
               *      available orders when none are fulfillable.
               */
              error NoSpecifiedOrdersAvailable();
              /**
               * @dev Revert with an error when attempting to fulfill an order with an
               *      offer for ETH outside of matching orders.
               */
              error InvalidNativeOfferItem();
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { ReentrancyErrors } from "../interfaces/ReentrancyErrors.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title ReentrancyGuard
           * @author 0age
           * @notice ReentrancyGuard contains a storage variable and related functionality
           *         for protecting against reentrancy.
           */
          contract ReentrancyGuard is ReentrancyErrors {
              // Prevent reentrant calls on protected functions.
              uint256 private _reentrancyGuard;
              /**
               * @dev Initialize the reentrancy guard during deployment.
               */
              constructor() {
                  // Initialize the reentrancy guard in a cleared state.
                  _reentrancyGuard = _NOT_ENTERED;
              }
              /**
               * @dev Internal function to ensure that the sentinel value for the
               *      reentrancy guard is not currently set and, if not, to set the
               *      sentinel value for the reentrancy guard.
               */
              function _setReentrancyGuard() internal {
                  // Ensure that the reentrancy guard is not already set.
                  _assertNonReentrant();
                  // Set the reentrancy guard.
                  _reentrancyGuard = _ENTERED;
              }
              /**
               * @dev Internal function to unset the reentrancy guard sentinel value.
               */
              function _clearReentrancyGuard() internal {
                  // Clear the reentrancy guard.
                  _reentrancyGuard = _NOT_ENTERED;
              }
              /**
               * @dev Internal view function to ensure that the sentinel value for the
                      reentrancy guard is not currently set.
               */
              function _assertNonReentrant() internal view {
                  // Ensure that the reentrancy guard is not currently set.
                  if (_reentrancyGuard != _NOT_ENTERED) {
                      revert NoReentrantCalls();
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title ReentrancyErrors
           * @author 0age
           * @notice ReentrancyErrors contains errors related to reentrancy.
           */
          interface ReentrancyErrors {
              /**
               * @dev Revert with an error when a caller attempts to reenter a protected
               *      function.
               */
              error NoReentrantCalls();
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          interface EIP1271Interface {
              function isValidSignature(bytes32 digest, bytes calldata signature)
                  external
                  view
                  returns (bytes4);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title SignatureVerificationErrors
           * @author 0age
           * @notice SignatureVerificationErrors contains all errors related to signature
           *         verification.
           */
          interface SignatureVerificationErrors {
              /**
               * @dev Revert with an error when a signature that does not contain a v
               *      value of 27 or 28 has been supplied.
               *
               * @param v The invalid v value.
               */
              error BadSignatureV(uint8 v);
              /**
               * @dev Revert with an error when the signer recovered by the supplied
               *      signature does not match the offerer or an allowed EIP-1271 signer
               *      as specified by the offerer in the event they are a contract.
               */
              error InvalidSigner();
              /**
               * @dev Revert with an error when a signer cannot be recovered from the
               *      supplied signature.
               */
              error InvalidSignature();
              /**
               * @dev Revert with an error when an EIP-1271 call to an account fails.
               */
              error BadContractSignature();
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import "./ConsiderationConstants.sol";
          /**
           * @title LowLevelHelpers
           * @author 0age
           * @notice LowLevelHelpers contains logic for performing various low-level
           *         operations.
           */
          contract LowLevelHelpers {
              /**
               * @dev Internal view function to staticcall an arbitrary target with given
               *      calldata. Note that no data is written to memory and no contract
               *      size check is performed.
               *
               * @param target   The account to staticcall.
               * @param callData The calldata to supply when staticcalling the target.
               *
               * @return success The status of the staticcall to the target.
               */
              function _staticcall(address target, bytes memory callData)
                  internal
                  view
                  returns (bool success)
              {
                  assembly {
                      // Perform the staticcall.
                      success := staticcall(
                          gas(),
                          target,
                          add(callData, OneWord),
                          mload(callData),
                          0,
                          0
                      )
                  }
              }
              /**
               * @dev Internal view function to revert and pass along the revert reason if
               *      data was returned by the last call and that the size of that data
               *      does not exceed the currently allocated memory size.
               */
              function _revertWithReasonIfOneIsReturned() internal view {
                  assembly {
                      // If it returned a message, bubble it up as long as sufficient gas
                      // remains to do so:
                      if returndatasize() {
                          // Ensure that sufficient gas is available to copy returndata
                          // while expanding memory where necessary. Start by computing
                          // the word size of returndata and allocated memory.
                          let returnDataWords := div(
                              add(returndatasize(), AlmostOneWord),
                              OneWord
                          )
                          // Note: use the free memory pointer in place of msize() to work
                          // around a Yul warning that prevents accessing msize directly
                          // when the IR pipeline is activated.
                          let msizeWords := div(mload(FreeMemoryPointerSlot), OneWord)
                          // Next, compute the cost of the returndatacopy.
                          let cost := mul(CostPerWord, returnDataWords)
                          // Then, compute cost of new memory allocation.
                          if gt(returnDataWords, msizeWords) {
                              cost := add(
                                  cost,
                                  add(
                                      mul(sub(returnDataWords, msizeWords), CostPerWord),
                                      div(
                                          sub(
                                              mul(returnDataWords, returnDataWords),
                                              mul(msizeWords, msizeWords)
                                          ),
                                          MemoryExpansionCoefficient
                                      )
                                  )
                              )
                          }
                          // Finally, add a small constant and compare to gas remaining;
                          // bubble up the revert data if enough gas is still available.
                          if lt(add(cost, ExtraGasBuffer), gas()) {
                              // Copy returndata to memory; overwrite existing memory.
                              returndatacopy(0, 0, returndatasize())
                              // Revert, specifying memory region with copied returndata.
                              revert(0, returndatasize())
                          }
                      }
                  }
              }
              /**
               * @dev Internal pure function to determine if the first word of returndata
               *      matches an expected magic value.
               *
               * @param expected The expected magic value.
               *
               * @return A boolean indicating whether the expected value matches the one
               *         located in the first word of returndata.
               */
              function _doesNotMatchMagic(bytes4 expected) internal pure returns (bool) {
                  // Declare a variable for the value held by the return data buffer.
                  bytes4 result;
                  // Utilize assembly in order to read directly from returndata buffer.
                  assembly {
                      // Only put result on stack if return data is exactly one word.
                      if eq(returndatasize(), OneWord) {
                          // Copy the word directly from return data into scratch space.
                          returndatacopy(0, 0, OneWord)
                          // Take value from scratch space and place it on the stack.
                          result := mload(0)
                      }
                  }
                  // Return a boolean indicating whether expected and located value match.
                  return result != expected;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { ItemType, Side } from "./ConsiderationEnums.sol";
          // prettier-ignore
          import {
              OfferItem,
              ConsiderationItem,
              ReceivedItem,
              OrderParameters,
              AdvancedOrder,
              Execution,
              FulfillmentComponent
          } from "./ConsiderationStructs.sol";
          import "./ConsiderationConstants.sol";
          // prettier-ignore
          import {
              FulfillmentApplicationErrors
          } from "../interfaces/FulfillmentApplicationErrors.sol";
          /**
           * @title FulfillmentApplier
           * @author 0age
           * @notice FulfillmentApplier contains logic related to applying fulfillments,
           *         both as part of order matching (where offer items are matched to
           *         consideration items) as well as fulfilling available orders (where
           *         order items and consideration items are independently aggregated).
           */
          contract FulfillmentApplier is FulfillmentApplicationErrors {
              /**
               * @dev Internal pure function to match offer items to consideration items
               *      on a group of orders via a supplied fulfillment.
               *
               * @param advancedOrders          The orders to match.
               * @param offerComponents         An array designating offer components to
               *                                match to consideration components.
               * @param considerationComponents An array designating consideration
               *                                components to match to offer components.
               *                                Note that each consideration amount must
               *                                be zero in order for the match operation
               *                                to be valid.
               *
               * @return execution The transfer performed as a result of the fulfillment.
               */
              function _applyFulfillment(
                  AdvancedOrder[] memory advancedOrders,
                  FulfillmentComponent[] calldata offerComponents,
                  FulfillmentComponent[] calldata considerationComponents
              ) internal pure returns (Execution memory execution) {
                  // Ensure 1+ of both offer and consideration components are supplied.
                  if (
                      offerComponents.length == 0 || considerationComponents.length == 0
                  ) {
                      revert OfferAndConsiderationRequiredOnFulfillment();
                  }
                  // Declare a new Execution struct.
                  Execution memory considerationExecution;
                  // Validate & aggregate consideration items to new Execution object.
                  _aggregateValidFulfillmentConsiderationItems(
                      advancedOrders,
                      considerationComponents,
                      considerationExecution
                  );
                  // Retrieve the consideration item from the execution struct.
                  ReceivedItem memory considerationItem = considerationExecution.item;
                  // Recipient does not need to be specified because it will always be set
                  // to that of the consideration.
                  // Validate & aggregate offer items to Execution object.
                  _aggregateValidFulfillmentOfferItems(
                      advancedOrders,
                      offerComponents,
                      execution
                  );
                  // Ensure offer and consideration share types, tokens and identifiers.
                  if (
                      execution.item.itemType != considerationItem.itemType ||
                      execution.item.token != considerationItem.token ||
                      execution.item.identifier != considerationItem.identifier
                  ) {
                      revert MismatchedFulfillmentOfferAndConsiderationComponents();
                  }
                  // If total consideration amount exceeds the offer amount...
                  if (considerationItem.amount > execution.item.amount) {
                      // Retrieve the first consideration component from the fulfillment.
                      FulfillmentComponent memory targetComponent = (
                          considerationComponents[0]
                      );
                      // Skip underflow check as the conditional being true implies that
                      // considerationItem.amount > execution.item.amount.
                      unchecked {
                          // Add excess consideration item amount to original order array.
                          advancedOrders[targetComponent.orderIndex]
                              .parameters
                              .consideration[targetComponent.itemIndex]
                              .startAmount = (considerationItem.amount -
                              execution.item.amount);
                      }
                      // Reduce total consideration amount to equal the offer amount.
                      considerationItem.amount = execution.item.amount;
                  } else {
                      // Retrieve the first offer component from the fulfillment.
                      FulfillmentComponent memory targetComponent = offerComponents[0];
                      // Skip underflow check as the conditional being false implies that
                      // execution.item.amount >= considerationItem.amount.
                      unchecked {
                          // Add excess offer item amount to the original array of orders.
                          advancedOrders[targetComponent.orderIndex]
                              .parameters
                              .offer[targetComponent.itemIndex]
                              .startAmount = (execution.item.amount -
                              considerationItem.amount);
                      }
                      // Reduce total offer amount to equal the consideration amount.
                      execution.item.amount = considerationItem.amount;
                  }
                  // Reuse consideration recipient.
                  execution.item.recipient = considerationItem.recipient;
                  // Return the final execution that will be triggered for relevant items.
                  return execution; // Execution(considerationItem, offerer, conduitKey);
              }
              /**
               * @dev Internal view function to aggregate offer or consideration items
               *      from a group of orders into a single execution via a supplied array
               *      of fulfillment components. Items that are not available to aggregate
               *      will not be included in the aggregated execution.
               *
               * @param advancedOrders        The orders to aggregate.
               * @param side                  The side (i.e. offer or consideration).
               * @param fulfillmentComponents An array designating item components to
               *                              aggregate if part of an available order.
               * @param fulfillerConduitKey   A bytes32 value indicating what conduit, if
               *                              any, to source the fulfiller's token
               *                              approvals from. The zero hash signifies that
               *                              no conduit should be used, with approvals
               *                              set directly on this contract.
               * @param recipient             The intended recipient for all received
               *                              items.
               *
               * @return execution The transfer performed as a result of the fulfillment.
               */
              function _aggregateAvailable(
                  AdvancedOrder[] memory advancedOrders,
                  Side side,
                  FulfillmentComponent[] memory fulfillmentComponents,
                  bytes32 fulfillerConduitKey,
                  address recipient
              ) internal view returns (Execution memory execution) {
                  // Skip overflow / underflow checks; conditions checked or unreachable.
                  unchecked {
                      // Retrieve fulfillment components array length and place on stack.
                      // Ensure at least one fulfillment component has been supplied.
                      if (fulfillmentComponents.length == 0) {
                          revert MissingFulfillmentComponentOnAggregation(side);
                      }
                      // If the fulfillment components are offer components...
                      if (side == Side.OFFER) {
                          // Set the supplied recipient on the execution item.
                          execution.item.recipient = payable(recipient);
                          // Return execution for aggregated items provided by offerer.
                          _aggregateValidFulfillmentOfferItems(
                              advancedOrders,
                              fulfillmentComponents,
                              execution
                          );
                      } else {
                          // Otherwise, fulfillment components are consideration
                          // components. Return execution for aggregated items provided by
                          // the fulfiller.
                          _aggregateValidFulfillmentConsiderationItems(
                              advancedOrders,
                              fulfillmentComponents,
                              execution
                          );
                          // Set the caller as the offerer on the execution.
                          execution.offerer = msg.sender;
                          // Set fulfiller conduit key as the conduit key on execution.
                          execution.conduitKey = fulfillerConduitKey;
                      }
                      // Set the offerer and recipient to null address if execution
                      // amount is zero. This will cause the execution item to be skipped.
                      if (execution.item.amount == 0) {
                          execution.offerer = address(0);
                          execution.item.recipient = payable(0);
                      }
                  }
              }
              /**
               * @dev Internal pure function to aggregate a group of offer items using
               *      supplied directives on which component items are candidates for
               *      aggregation, skipping items on orders that are not available.
               *
               * @param advancedOrders  The orders to aggregate offer items from.
               * @param offerComponents An array of FulfillmentComponent structs
               *                        indicating the order index and item index of each
               *                        candidate offer item for aggregation.
               * @param execution       The execution to apply the aggregation to.
               */
              function _aggregateValidFulfillmentOfferItems(
                  AdvancedOrder[] memory advancedOrders,
                  FulfillmentComponent[] memory offerComponents,
                  Execution memory execution
              ) internal pure {
                  assembly {
                      // Declare function for reverts on invalid fulfillment data.
                      function throwInvalidFulfillmentComponentData() {
                          // Store the InvalidFulfillmentComponentData error signature.
                          mstore(0, InvalidFulfillmentComponentData_error_signature)
                          // Return, supplying InvalidFulfillmentComponentData signature.
                          revert(0, InvalidFulfillmentComponentData_error_len)
                      }
                      // Declare function for reverts due to arithmetic overflows.
                      function throwOverflow() {
                          // Store the Panic error signature.
                          mstore(0, Panic_error_signature)
                          // Store the arithmetic (0x11) panic code as initial argument.
                          mstore(Panic_error_offset, Panic_arithmetic)
                          // Return, supplying Panic signature and arithmetic code.
                          revert(0, Panic_error_length)
                      }
                      // Get position in offerComponents head.
                      let fulfillmentHeadPtr := add(offerComponents, OneWord)
                      // Retrieve the order index using the fulfillment pointer.
                      let orderIndex := mload(mload(fulfillmentHeadPtr))
                      // Ensure that the order index is not out of range.
                      if iszero(lt(orderIndex, mload(advancedOrders))) {
                          throwInvalidFulfillmentComponentData()
                      }
                      // Read advancedOrders[orderIndex] pointer from its array head.
                      let orderPtr := mload(
                          // Calculate head position of advancedOrders[orderIndex].
                          add(add(advancedOrders, OneWord), mul(orderIndex, OneWord))
                      )
                      // Read the pointer to OrderParameters from the AdvancedOrder.
                      let paramsPtr := mload(orderPtr)
                      // Load the offer array pointer.
                      let offerArrPtr := mload(
                          add(paramsPtr, OrderParameters_offer_head_offset)
                      )
                      // Retrieve item index using an offset of the fulfillment pointer.
                      let itemIndex := mload(
                          add(mload(fulfillmentHeadPtr), Fulfillment_itemIndex_offset)
                      )
                      // Only continue if the fulfillment is not invalid.
                      if iszero(lt(itemIndex, mload(offerArrPtr))) {
                          throwInvalidFulfillmentComponentData()
                      }
                      // Retrieve consideration item pointer using the item index.
                      let offerItemPtr := mload(
                          add(
                              // Get pointer to beginning of receivedItem.
                              add(offerArrPtr, OneWord),
                              // Calculate offset to pointer for desired order.
                              mul(itemIndex, OneWord)
                          )
                      )
                      // Declare a variable for the final aggregated item amount.
                      let amount := 0
                      // Create variable to track errors encountered with amount.
                      let errorBuffer := 0
                      // Only add offer amount to execution amount on a nonzero numerator.
                      if mload(add(orderPtr, AdvancedOrder_numerator_offset)) {
                          // Retrieve amount pointer using consideration item pointer.
                          let amountPtr := add(offerItemPtr, Common_amount_offset)
                          // Set the amount.
                          amount := mload(amountPtr)
                          // Zero out amount on item to indicate it is credited.
                          mstore(amountPtr, 0)
                          // Buffer indicating whether issues were found.
                          errorBuffer := iszero(amount)
                      }
                      // Retrieve the received item pointer.
                      let receivedItemPtr := mload(execution)
                      // Set the item type on the received item.
                      mstore(receivedItemPtr, mload(offerItemPtr))
                      // Set the token on the received item.
                      mstore(
                          add(receivedItemPtr, Common_token_offset),
                          mload(add(offerItemPtr, Common_token_offset))
                      )
                      // Set the identifier on the received item.
                      mstore(
                          add(receivedItemPtr, Common_identifier_offset),
                          mload(add(offerItemPtr, Common_identifier_offset))
                      )
                      // Set the offerer on returned execution using order pointer.
                      mstore(add(execution, Execution_offerer_offset), mload(paramsPtr))
                      // Set conduitKey on returned execution via offset of order pointer.
                      mstore(
                          add(execution, Execution_conduit_offset),
                          mload(add(paramsPtr, OrderParameters_conduit_offset))
                      )
                      // Calculate the hash of (itemType, token, identifier).
                      let dataHash := keccak256(
                          receivedItemPtr,
                          ReceivedItem_CommonParams_size
                      )
                      // Get position one word past last element in head of array.
                      let endPtr := add(
                          offerComponents,
                          mul(mload(offerComponents), OneWord)
                      )
                      // Iterate over remaining offer components.
                      // prettier-ignore
                      for {} lt(fulfillmentHeadPtr,  endPtr) {} {
                          // Increment the pointer to the fulfillment head by one word.
                          fulfillmentHeadPtr := add(fulfillmentHeadPtr, OneWord)
                          // Get the order index using the fulfillment pointer.
                          orderIndex := mload(mload(fulfillmentHeadPtr))
                          // Ensure the order index is in range.
                          if iszero(lt(orderIndex, mload(advancedOrders))) {
                            throwInvalidFulfillmentComponentData()
                          }
                          // Get pointer to AdvancedOrder element.
                          orderPtr := mload(
                              add(
                                  add(advancedOrders, OneWord),
                                  mul(orderIndex, OneWord)
                              )
                          )
                          // Only continue if numerator is not zero.
                          if iszero(mload(
                              add(orderPtr, AdvancedOrder_numerator_offset)
                          )) {
                            continue
                          }
                          // Read the pointer to OrderParameters from the AdvancedOrder.
                          paramsPtr := mload(orderPtr)
                          // Load offer array pointer.
                          offerArrPtr := mload(
                              add(
                                  paramsPtr,
                                  OrderParameters_offer_head_offset
                              )
                          )
                          // Get the item index using the fulfillment pointer.
                          itemIndex := mload(add(mload(fulfillmentHeadPtr), OneWord))
                          // Throw if itemIndex is out of the range of array.
                          if iszero(
                              lt(itemIndex, mload(offerArrPtr))
                          ) {
                              throwInvalidFulfillmentComponentData()
                          }
                          // Retrieve offer item pointer using index.
                          offerItemPtr := mload(
                              add(
                                  // Get pointer to beginning of receivedItem.
                                  add(offerArrPtr, OneWord),
                                  // Use offset to pointer for desired order.
                                  mul(itemIndex, OneWord)
                              )
                          )
                          // Retrieve amount pointer using offer item pointer.
                          let amountPtr := add(
                                offerItemPtr,
                                Common_amount_offset
                          )
                          // Add offer amount to execution amount.
                          let newAmount := add(amount, mload(amountPtr))
                          // Update error buffer: 1 = zero amount, 2 = overflow, 3 = both.
                          errorBuffer := or(
                            errorBuffer,
                            or(
                              shl(1, lt(newAmount, amount)),
                              iszero(mload(amountPtr))
                            )
                          )
                          // Update the amount to the new, summed amount.
                          amount := newAmount
                          // Zero out amount on original item to indicate it is credited.
                          mstore(amountPtr, 0)
                          // Ensure the indicated item matches original item.
                          if iszero(
                              and(
                                  and(
                                    // The offerer must match on both items.
                                    eq(
                                        mload(paramsPtr),
                                        mload(
                                            add(execution, Execution_offerer_offset)
                                        )
                                    ),
                                    // The conduit key must match on both items.
                                    eq(
                                        mload(
                                            add(
                                                paramsPtr,
                                                OrderParameters_conduit_offset
                                            )
                                        ),
                                        mload(
                                            add(
                                                execution,
                                                Execution_conduit_offset
                                            )
                                        )
                                    )
                                  ),
                                  // The itemType, token, and identifier must match.
                                  eq(
                                      dataHash,
                                      keccak256(
                                          offerItemPtr,
                                          ReceivedItem_CommonParams_size
                                      )
                                  )
                              )
                          ) {
                              // Throw if any of the requirements are not met.
                              throwInvalidFulfillmentComponentData()
                          }
                      }
                      // Write final amount to execution.
                      mstore(add(mload(execution), Common_amount_offset), amount)
                      // Determine whether the error buffer contains a nonzero error code.
                      if errorBuffer {
                          // If errorBuffer is 1, an item had an amount of zero.
                          if eq(errorBuffer, 1) {
                              // Store the MissingItemAmount error signature.
                              mstore(0, MissingItemAmount_error_signature)
                              // Return, supplying MissingItemAmount signature.
                              revert(0, MissingItemAmount_error_len)
                          }
                          // If errorBuffer is not 1 or 0, the sum overflowed.
                          // Panic!
                          throwOverflow()
                      }
                  }
              }
              /**
               * @dev Internal pure function to aggregate a group of consideration items
               *      using supplied directives on which component items are candidates
               *      for aggregation, skipping items on orders that are not available.
               *
               * @param advancedOrders          The orders to aggregate consideration
               *                                items from.
               * @param considerationComponents An array of FulfillmentComponent structs
               *                                indicating the order index and item index
               *                                of each candidate consideration item for
               *                                aggregation.
               * @param execution       The execution to apply the aggregation to.
               */
              function _aggregateValidFulfillmentConsiderationItems(
                  AdvancedOrder[] memory advancedOrders,
                  FulfillmentComponent[] memory considerationComponents,
                  Execution memory execution
              ) internal pure {
                  // Utilize assembly in order to efficiently aggregate the items.
                  assembly {
                      // Declare function for reverts on invalid fulfillment data.
                      function throwInvalidFulfillmentComponentData() {
                          // Store the InvalidFulfillmentComponentData error signature.
                          mstore(0, InvalidFulfillmentComponentData_error_signature)
                          // Return, supplying InvalidFulfillmentComponentData signature.
                          revert(0, InvalidFulfillmentComponentData_error_len)
                      }
                      // Declare function for reverts due to arithmetic overflows.
                      function throwOverflow() {
                          // Store the Panic error signature.
                          mstore(0, Panic_error_signature)
                          // Store the arithmetic (0x11) panic code as initial argument.
                          mstore(Panic_error_offset, Panic_arithmetic)
                          // Return, supplying Panic signature and arithmetic code.
                          revert(0, Panic_error_length)
                      }
                      // Get position in considerationComponents head.
                      let fulfillmentHeadPtr := add(considerationComponents, OneWord)
                      // Retrieve the order index using the fulfillment pointer.
                      let orderIndex := mload(mload(fulfillmentHeadPtr))
                      // Ensure that the order index is not out of range.
                      if iszero(lt(orderIndex, mload(advancedOrders))) {
                          throwInvalidFulfillmentComponentData()
                      }
                      // Read advancedOrders[orderIndex] pointer from its array head.
                      let orderPtr := mload(
                          // Calculate head position of advancedOrders[orderIndex].
                          add(add(advancedOrders, OneWord), mul(orderIndex, OneWord))
                      )
                      // Load consideration array pointer.
                      let considerationArrPtr := mload(
                          add(
                              // Read pointer to OrderParameters from the AdvancedOrder.
                              mload(orderPtr),
                              OrderParameters_consideration_head_offset
                          )
                      )
                      // Retrieve item index using an offset of the fulfillment pointer.
                      let itemIndex := mload(
                          add(mload(fulfillmentHeadPtr), Fulfillment_itemIndex_offset)
                      )
                      // Ensure that the order index is not out of range.
                      if iszero(lt(itemIndex, mload(considerationArrPtr))) {
                          throwInvalidFulfillmentComponentData()
                      }
                      // Retrieve consideration item pointer using the item index.
                      let considerationItemPtr := mload(
                          add(
                              // Get pointer to beginning of receivedItem.
                              add(considerationArrPtr, OneWord),
                              // Calculate offset to pointer for desired order.
                              mul(itemIndex, OneWord)
                          )
                      )
                      // Declare a variable for the final aggregated item amount.
                      let amount := 0
                      // Create variable to track errors encountered with amount.
                      let errorBuffer := 0
                      // Only add consideration amount to execution amount if numerator is
                      // greater than zero.
                      if mload(add(orderPtr, AdvancedOrder_numerator_offset)) {
                          // Retrieve amount pointer using consideration item pointer.
                          let amountPtr := add(considerationItemPtr, Common_amount_offset)
                          // Set the amount.
                          amount := mload(amountPtr)
                          // Set error bit if amount is zero.
                          errorBuffer := iszero(amount)
                          // Zero out amount on item to indicate it is credited.
                          mstore(amountPtr, 0)
                      }
                      // Retrieve ReceivedItem pointer from Execution.
                      let receivedItem := mload(execution)
                      // Set the item type on the received item.
                      mstore(receivedItem, mload(considerationItemPtr))
                      // Set the token on the received item.
                      mstore(
                          add(receivedItem, Common_token_offset),
                          mload(add(considerationItemPtr, Common_token_offset))
                      )
                      // Set the identifier on the received item.
                      mstore(
                          add(receivedItem, Common_identifier_offset),
                          mload(add(considerationItemPtr, Common_identifier_offset))
                      )
                      // Set the recipient on the received item.
                      mstore(
                          add(receivedItem, ReceivedItem_recipient_offset),
                          mload(
                              add(
                                  considerationItemPtr,
                                  ConsiderationItem_recipient_offset
                              )
                          )
                      )
                      // Calculate the hash of (itemType, token, identifier).
                      let dataHash := keccak256(
                          receivedItem,
                          ReceivedItem_CommonParams_size
                      )
                      // Get position one word past last element in head of array.
                      let endPtr := add(
                          considerationComponents,
                          mul(mload(considerationComponents), OneWord)
                      )
                      // Iterate over remaining offer components.
                      // prettier-ignore
                      for {} lt(fulfillmentHeadPtr,  endPtr) {} {
                          // Increment position in considerationComponents head.
                          fulfillmentHeadPtr := add(fulfillmentHeadPtr, OneWord)
                          // Get the order index using the fulfillment pointer.
                          orderIndex := mload(mload(fulfillmentHeadPtr))
                          // Ensure the order index is in range.
                          if iszero(lt(orderIndex, mload(advancedOrders))) {
                            throwInvalidFulfillmentComponentData()
                          }
                          // Get pointer to AdvancedOrder element.
                          orderPtr := mload(
                              add(
                                  add(advancedOrders, OneWord),
                                  mul(orderIndex, OneWord)
                              )
                          )
                          // Only continue if numerator is not zero.
                          if iszero(
                              mload(add(orderPtr, AdvancedOrder_numerator_offset))
                          ) {
                            continue
                          }
                          // Load consideration array pointer from OrderParameters.
                          considerationArrPtr := mload(
                              add(
                                  // Get pointer to OrderParameters from AdvancedOrder.
                                  mload(orderPtr),
                                  OrderParameters_consideration_head_offset
                              )
                          )
                          // Get the item index using the fulfillment pointer.
                          itemIndex := mload(add(mload(fulfillmentHeadPtr), OneWord))
                          // Check if itemIndex is within the range of array.
                          if iszero(lt(itemIndex, mload(considerationArrPtr))) {
                              throwInvalidFulfillmentComponentData()
                          }
                          // Retrieve consideration item pointer using index.
                          considerationItemPtr := mload(
                              add(
                                  // Get pointer to beginning of receivedItem.
                                  add(considerationArrPtr, OneWord),
                                  // Use offset to pointer for desired order.
                                  mul(itemIndex, OneWord)
                              )
                          )
                          // Retrieve amount pointer using consideration item pointer.
                          let amountPtr := add(
                                considerationItemPtr,
                                Common_amount_offset
                          )
                          // Add offer amount to execution amount.
                          let newAmount := add(amount, mload(amountPtr))
                          // Update error buffer: 1 = zero amount, 2 = overflow, 3 = both.
                          errorBuffer := or(
                            errorBuffer,
                            or(
                              shl(1, lt(newAmount, amount)),
                              iszero(mload(amountPtr))
                            )
                          )
                          // Update the amount to the new, summed amount.
                          amount := newAmount
                          // Zero out amount on original item to indicate it is credited.
                          mstore(amountPtr, 0)
                          // Ensure the indicated item matches original item.
                          if iszero(
                              and(
                                  // Item recipients must match.
                                  eq(
                                      mload(
                                          add(
                                              considerationItemPtr,
                                              ConsiderItem_recipient_offset
                                          )
                                      ),
                                      mload(
                                          add(
                                              receivedItem,
                                              ReceivedItem_recipient_offset
                                          )
                                      )
                                  ),
                                  // The itemType, token, identifier must match.
                                  eq(
                                    dataHash,
                                    keccak256(
                                      considerationItemPtr,
                                      ReceivedItem_CommonParams_size
                                    )
                                  )
                              )
                          ) {
                              // Throw if any of the requirements are not met.
                              throwInvalidFulfillmentComponentData()
                          }
                      }
                      // Write final amount to execution.
                      mstore(add(receivedItem, Common_amount_offset), amount)
                      // Determine whether the error buffer contains a nonzero error code.
                      if errorBuffer {
                          // If errorBuffer is 1, an item had an amount of zero.
                          if eq(errorBuffer, 1) {
                              // Store the MissingItemAmount error signature.
                              mstore(0, MissingItemAmount_error_signature)
                              // Return, supplying MissingItemAmount signature.
                              revert(0, MissingItemAmount_error_len)
                          }
                          // If errorBuffer is not 1 or 0, the sum overflowed.
                          // Panic!
                          throwOverflow()
                      }
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { Side } from "../lib/ConsiderationEnums.sol";
          /**
           * @title FulfillmentApplicationErrors
           * @author 0age
           * @notice FulfillmentApplicationErrors contains errors related to fulfillment
           *         application and aggregation.
           */
          interface FulfillmentApplicationErrors {
              /**
               * @dev Revert with an error when a fulfillment is provided that does not
               *      declare at least one component as part of a call to fulfill
               *      available orders.
               */
              error MissingFulfillmentComponentOnAggregation(Side side);
              /**
               * @dev Revert with an error when a fulfillment is provided that does not
               *      declare at least one offer component and at least one consideration
               *      component.
               */
              error OfferAndConsiderationRequiredOnFulfillment();
              /**
               * @dev Revert with an error when the initial offer item named by a
               *      fulfillment component does not match the type, token, identifier,
               *      or conduit preference of the initial consideration item.
               */
              error MismatchedFulfillmentOfferAndConsiderationComponents();
              /**
               * @dev Revert with an error when an order or item index are out of range
               *      or a fulfillment component does not match the type, token,
               *      identifier, or conduit preference of the initial consideration item.
               */
              error InvalidFulfillmentComponentData();
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { ItemType, Side } from "./ConsiderationEnums.sol";
          // prettier-ignore
          import {
              OfferItem,
              ConsiderationItem,
              OrderParameters,
              AdvancedOrder,
              CriteriaResolver
          } from "./ConsiderationStructs.sol";
          import "./ConsiderationConstants.sol";
          // prettier-ignore
          import {
              CriteriaResolutionErrors
          } from "../interfaces/CriteriaResolutionErrors.sol";
          /**
           * @title CriteriaResolution
           * @author 0age
           * @notice CriteriaResolution contains a collection of pure functions related to
           *         resolving criteria-based items.
           */
          contract CriteriaResolution is CriteriaResolutionErrors {
              /**
               * @dev Internal pure function to apply criteria resolvers containing
               *      specific token identifiers and associated proofs to order items.
               *
               * @param advancedOrders     The orders to apply criteria resolvers to.
               * @param criteriaResolvers  An array where each element contains a
               *                           reference to a specific order as well as that
               *                           order's offer or consideration, a token
               *                           identifier, and a proof that the supplied token
               *                           identifier is contained in the order's merkle
               *                           root. Note that a root of zero indicates that
               *                           any transferable token identifier is valid and
               *                           that no proof needs to be supplied.
               */
              function _applyCriteriaResolvers(
                  AdvancedOrder[] memory advancedOrders,
                  CriteriaResolver[] memory criteriaResolvers
              ) internal pure {
                  // Skip overflow checks as all for loops are indexed starting at zero.
                  unchecked {
                      // Retrieve length of criteria resolvers array and place on stack.
                      uint256 totalCriteriaResolvers = criteriaResolvers.length;
                      // Retrieve length of orders array and place on stack.
                      uint256 totalAdvancedOrders = advancedOrders.length;
                      // Iterate over each criteria resolver.
                      for (uint256 i = 0; i < totalCriteriaResolvers; ++i) {
                          // Retrieve the criteria resolver.
                          CriteriaResolver memory criteriaResolver = (
                              criteriaResolvers[i]
                          );
                          // Read the order index from memory and place it on the stack.
                          uint256 orderIndex = criteriaResolver.orderIndex;
                          // Ensure that the order index is in range.
                          if (orderIndex >= totalAdvancedOrders) {
                              revert OrderCriteriaResolverOutOfRange();
                          }
                          // Skip criteria resolution for order if not fulfilled.
                          if (advancedOrders[orderIndex].numerator == 0) {
                              continue;
                          }
                          // Retrieve the parameters for the order.
                          OrderParameters memory orderParameters = (
                              advancedOrders[orderIndex].parameters
                          );
                          // Read component index from memory and place it on the stack.
                          uint256 componentIndex = criteriaResolver.index;
                          // Declare values for item's type and criteria.
                          ItemType itemType;
                          uint256 identifierOrCriteria;
                          // If the criteria resolver refers to an offer item...
                          if (criteriaResolver.side == Side.OFFER) {
                              // Retrieve the offer.
                              OfferItem[] memory offer = orderParameters.offer;
                              // Ensure that the component index is in range.
                              if (componentIndex >= offer.length) {
                                  revert OfferCriteriaResolverOutOfRange();
                              }
                              // Retrieve relevant item using the component index.
                              OfferItem memory offerItem = offer[componentIndex];
                              // Read item type and criteria from memory & place on stack.
                              itemType = offerItem.itemType;
                              identifierOrCriteria = offerItem.identifierOrCriteria;
                              // Optimistically update item type to remove criteria usage.
                              // Use assembly to operate on ItemType enum as a number.
                              ItemType newItemType;
                              assembly {
                                  // Item type 4 becomes 2 and item type 5 becomes 3.
                                  newItemType := sub(3, eq(itemType, 4))
                              }
                              offerItem.itemType = newItemType;
                              // Optimistically update identifier w/ supplied identifier.
                              offerItem.identifierOrCriteria = criteriaResolver
                                  .identifier;
                          } else {
                              // Otherwise, the resolver refers to a consideration item.
                              ConsiderationItem[] memory consideration = (
                                  orderParameters.consideration
                              );
                              // Ensure that the component index is in range.
                              if (componentIndex >= consideration.length) {
                                  revert ConsiderationCriteriaResolverOutOfRange();
                              }
                              // Retrieve relevant item using order and component index.
                              ConsiderationItem memory considerationItem = (
                                  consideration[componentIndex]
                              );
                              // Read item type and criteria from memory & place on stack.
                              itemType = considerationItem.itemType;
                              identifierOrCriteria = (
                                  considerationItem.identifierOrCriteria
                              );
                              // Optimistically update item type to remove criteria usage.
                              // Use assembly to operate on ItemType enum as a number.
                              ItemType newItemType;
                              assembly {
                                  // Item type 4 becomes 2 and item type 5 becomes 3.
                                  newItemType := sub(3, eq(itemType, 4))
                              }
                              considerationItem.itemType = newItemType;
                              // Optimistically update identifier w/ supplied identifier.
                              considerationItem.identifierOrCriteria = (
                                  criteriaResolver.identifier
                              );
                          }
                          // Ensure the specified item type indicates criteria usage.
                          if (!_isItemWithCriteria(itemType)) {
                              revert CriteriaNotEnabledForItem();
                          }
                          // If criteria is not 0 (i.e. a collection-wide offer)...
                          if (identifierOrCriteria != uint256(0)) {
                              // Verify identifier inclusion in criteria root using proof.
                              _verifyProof(
                                  criteriaResolver.identifier,
                                  identifierOrCriteria,
                                  criteriaResolver.criteriaProof
                              );
                          }
                      }
                      // Iterate over each advanced order.
                      for (uint256 i = 0; i < totalAdvancedOrders; ++i) {
                          // Retrieve the advanced order.
                          AdvancedOrder memory advancedOrder = advancedOrders[i];
                          // Skip criteria resolution for order if not fulfilled.
                          if (advancedOrder.numerator == 0) {
                              continue;
                          }
                          // Retrieve the parameters for the order.
                          OrderParameters memory orderParameters = (
                              advancedOrder.parameters
                          );
                          // Read consideration length from memory and place on stack.
                          uint256 totalItems = orderParameters.consideration.length;
                          // Iterate over each consideration item on the order.
                          for (uint256 j = 0; j < totalItems; ++j) {
                              // Ensure item type no longer indicates criteria usage.
                              if (
                                  _isItemWithCriteria(
                                      orderParameters.consideration[j].itemType
                                  )
                              ) {
                                  revert UnresolvedConsiderationCriteria();
                              }
                          }
                          // Read offer length from memory and place on stack.
                          totalItems = orderParameters.offer.length;
                          // Iterate over each offer item on the order.
                          for (uint256 j = 0; j < totalItems; ++j) {
                              // Ensure item type no longer indicates criteria usage.
                              if (
                                  _isItemWithCriteria(orderParameters.offer[j].itemType)
                              ) {
                                  revert UnresolvedOfferCriteria();
                              }
                          }
                      }
                  }
              }
              /**
               * @dev Internal pure function to check whether a given item type represents
               *      a criteria-based ERC721 or ERC1155 item (e.g. an item that can be
               *      resolved to one of a number of different identifiers at the time of
               *      order fulfillment).
               *
               * @param itemType The item type in question.
               *
               * @return withCriteria A boolean indicating that the item type in question
               *                      represents a criteria-based item.
               */
              function _isItemWithCriteria(ItemType itemType)
                  internal
                  pure
                  returns (bool withCriteria)
              {
                  // ERC721WithCriteria is ItemType 4. ERC1155WithCriteria is ItemType 5.
                  assembly {
                      withCriteria := gt(itemType, 3)
                  }
              }
              /**
               * @dev Internal pure function to ensure that a given element is contained
               *      in a merkle root via a supplied proof.
               *
               * @param leaf  The element for which to prove inclusion.
               * @param root  The merkle root that inclusion will be proved against.
               * @param proof The merkle proof.
               */
              function _verifyProof(
                  uint256 leaf,
                  uint256 root,
                  bytes32[] memory proof
              ) internal pure {
                  // Declare a variable that will be used to determine proof validity.
                  bool isValid;
                  // Utilize assembly to efficiently verify the proof against the root.
                  assembly {
                      // Store the leaf at the beginning of scratch space.
                      mstore(0, leaf)
                      // Derive the hash of the leaf to use as the initial proof element.
                      let computedHash := keccak256(0, OneWord)
                      // Based on: https://github.com/Rari-Capital/solmate/blob/v7/src/utils/MerkleProof.sol
                      // Get memory start location of the first element in proof array.
                      let data := add(proof, OneWord)
                      // Iterate over each proof element to compute the root hash.
                      for {
                          // Left shift by 5 is equivalent to multiplying by 0x20.
                          let end := add(data, shl(5, mload(proof)))
                      } lt(data, end) {
                          // Increment by one word at a time.
                          data := add(data, OneWord)
                      } {
                          // Get the proof element.
                          let loadedData := mload(data)
                          // Sort proof elements and place them in scratch space.
                          // Slot of `computedHash` in scratch space.
                          // If the condition is true: 0x20, otherwise: 0x00.
                          let scratch := shl(5, gt(computedHash, loadedData))
                          // Store elements to hash contiguously in scratch space. Scratch
                          // space is 64 bytes (0x00 - 0x3f) & both elements are 32 bytes.
                          mstore(scratch, computedHash)
                          mstore(xor(scratch, OneWord), loadedData)
                          // Derive the updated hash.
                          computedHash := keccak256(0, TwoWords)
                      }
                      // Compare the final hash to the supplied root.
                      isValid := eq(computedHash, root)
                  }
                  // Revert if computed hash does not equal supplied root.
                  if (!isValid) {
                      revert InvalidProof();
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title CriteriaResolutionErrors
           * @author 0age
           * @notice CriteriaResolutionErrors contains all errors related to criteria
           *         resolution.
           */
          interface CriteriaResolutionErrors {
              /**
               * @dev Revert with an error when providing a criteria resolver that refers
               *      to an order that has not been supplied.
               */
              error OrderCriteriaResolverOutOfRange();
              /**
               * @dev Revert with an error if an offer item still has unresolved criteria
               *      after applying all criteria resolvers.
               */
              error UnresolvedOfferCriteria();
              /**
               * @dev Revert with an error if a consideration item still has unresolved
               *      criteria after applying all criteria resolvers.
               */
              error UnresolvedConsiderationCriteria();
              /**
               * @dev Revert with an error when providing a criteria resolver that refers
               *      to an order with an offer item that has not been supplied.
               */
              error OfferCriteriaResolverOutOfRange();
              /**
               * @dev Revert with an error when providing a criteria resolver that refers
               *      to an order with a consideration item that has not been supplied.
               */
              error ConsiderationCriteriaResolverOutOfRange();
              /**
               * @dev Revert with an error when providing a criteria resolver that refers
               *      to an order with an item that does not expect a criteria to be
               *      resolved.
               */
              error CriteriaNotEnabledForItem();
              /**
               * @dev Revert with an error when providing a criteria resolver that
               *      contains an invalid proof with respect to the given item and
               *      chosen identifier.
               */
              error InvalidProof();
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { ZoneInterface } from "../interfaces/ZoneInterface.sol";
          // prettier-ignore
          import {
              AdvancedOrder,
              CriteriaResolver
          } from "../lib/ConsiderationStructs.sol";
          contract TestZone is ZoneInterface {
              function isValidOrder(
                  bytes32 orderHash,
                  address caller,
                  address offerer,
                  bytes32 zoneHash
              ) external pure override returns (bytes4 validOrderMagicValue) {
                  orderHash;
                  caller;
                  offerer;
                  if (zoneHash == bytes32(uint256(1))) {
                      revert("Revert on zone hash 1");
                  } else if (zoneHash == bytes32(uint256(2))) {
                      assembly {
                          revert(0, 0)
                      }
                  }
                  validOrderMagicValue = zoneHash != bytes32(uint256(3))
                      ? ZoneInterface.isValidOrder.selector
                      : bytes4(0xffffffff);
              }
              function isValidOrderIncludingExtraData(
                  bytes32 orderHash,
                  address caller,
                  AdvancedOrder calldata order,
                  bytes32[] calldata priorOrderHashes,
                  CriteriaResolver[] calldata criteriaResolvers
              ) external pure override returns (bytes4 validOrderMagicValue) {
                  orderHash;
                  caller;
                  order;
                  priorOrderHashes;
                  criteriaResolvers;
                  if (order.extraData.length == 4) {
                      revert("Revert on extraData length 4");
                  } else if (order.extraData.length == 5) {
                      assembly {
                          revert(0, 0)
                      }
                  }
                  validOrderMagicValue = order.parameters.zoneHash != bytes32(uint256(3))
                      ? ZoneInterface.isValidOrder.selector
                      : bytes4(0xffffffff);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // prettier-ignore
          import {
              AdvancedOrder,
              CriteriaResolver
          } from "../lib/ConsiderationStructs.sol";
          interface ZoneInterface {
              // Called by Consideration whenever extraData is not provided by the caller.
              function isValidOrder(
                  bytes32 orderHash,
                  address caller,
                  address offerer,
                  bytes32 zoneHash
              ) external view returns (bytes4 validOrderMagicValue);
              // Called by Consideration whenever any extraData is provided by the caller.
              function isValidOrderIncludingExtraData(
                  bytes32 orderHash,
                  address caller,
                  AdvancedOrder calldata order,
                  bytes32[] calldata priorOrderHashes,
                  CriteriaResolver[] calldata criteriaResolvers
              ) external view returns (bytes4 validOrderMagicValue);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { ZoneInterface } from "../interfaces/ZoneInterface.sol";
          import { OrderType } from "./ConsiderationEnums.sol";
          // prettier-ignore
          import { AdvancedOrder, CriteriaResolver } from "./ConsiderationStructs.sol";
          import "./ConsiderationConstants.sol";
          // prettier-ignore
          import {
              ZoneInteractionErrors
          } from "../interfaces/ZoneInteractionErrors.sol";
          import { LowLevelHelpers } from "./LowLevelHelpers.sol";
          /**
           * @title ZoneInteraction
           * @author 0age
           * @notice ZoneInteraction contains logic related to interacting with zones.
           */
          contract ZoneInteraction is ZoneInteractionErrors, LowLevelHelpers {
              /**
               * @dev Internal view function to determine if an order has a restricted
               *      order type and, if so, to ensure that either the offerer or the zone
               *      are the fulfiller or that a staticcall to `isValidOrder` on the zone
               *      returns a magic value indicating that the order is currently valid.
               *
               * @param orderHash The hash of the order.
               * @param zoneHash  The hash to provide upon calling the zone.
               * @param orderType The type of the order.
               * @param offerer   The offerer in question.
               * @param zone      The zone in question.
               */
              function _assertRestrictedBasicOrderValidity(
                  bytes32 orderHash,
                  bytes32 zoneHash,
                  OrderType orderType,
                  address offerer,
                  address zone
              ) internal view {
                  // Order type 2-3 require zone or offerer be caller or zone to approve.
                  if (
                      uint256(orderType) > 1 &&
                      msg.sender != zone &&
                      msg.sender != offerer
                  ) {
                      // Perform minimal staticcall to the zone.
                      _callIsValidOrder(zone, orderHash, offerer, zoneHash);
                  }
              }
              function _callIsValidOrder(
                  address zone,
                  bytes32 orderHash,
                  address offerer,
                  bytes32 zoneHash
              ) internal view {
                  // Perform minimal staticcall to the zone.
                  bool success = _staticcall(
                      zone,
                      abi.encodeWithSelector(
                          ZoneInterface.isValidOrder.selector,
                          orderHash,
                          msg.sender,
                          offerer,
                          zoneHash
                      )
                  );
                  // Ensure call was successful and returned the correct magic value.
                  _assertIsValidOrderStaticcallSuccess(success, orderHash);
              }
              /**
               * @dev Internal view function to determine whether an order is a restricted
               *      order and, if so, to ensure that it was either submitted by the
               *      offerer or the zone for the order, or that the zone returns the
               *      expected magic value upon performing a staticcall to `isValidOrder`
               *      or `isValidOrderIncludingExtraData` depending on whether the order
               *      fulfillment specifies extra data or criteria resolvers.
               *
               * @param advancedOrder     The advanced order in question.
               * @param criteriaResolvers An array where each element contains a reference
               *                          to a specific offer or consideration, a token
               *                          identifier, and a proof that the supplied token
               *                          identifier is contained in the order's merkle
               *                          root. Note that a criteria of zero indicates
               *                          that any (transferable) token identifier is
               *                          valid and that no proof needs to be supplied.
               * @param priorOrderHashes  The order hashes of each order supplied prior to
               *                          the current order as part of a "match" variety
               *                          of order fulfillment (e.g. this array will be
               *                          empty for single or "fulfill available").
               * @param orderHash         The hash of the order.
               * @param zoneHash          The hash to provide upon calling the zone.
               * @param orderType         The type of the order.
               * @param offerer           The offerer in question.
               * @param zone              The zone in question.
               */
              function _assertRestrictedAdvancedOrderValidity(
                  AdvancedOrder memory advancedOrder,
                  CriteriaResolver[] memory criteriaResolvers,
                  bytes32[] memory priorOrderHashes,
                  bytes32 orderHash,
                  bytes32 zoneHash,
                  OrderType orderType,
                  address offerer,
                  address zone
              ) internal view {
                  // Order type 2-3 require zone or offerer be caller or zone to approve.
                  if (
                      uint256(orderType) > 1 &&
                      msg.sender != zone &&
                      msg.sender != offerer
                  ) {
                      // If no extraData or criteria resolvers are supplied...
                      if (
                          advancedOrder.extraData.length == 0 &&
                          criteriaResolvers.length == 0
                      ) {
                          // Perform minimal staticcall to the zone.
                          _callIsValidOrder(zone, orderHash, offerer, zoneHash);
                      } else {
                          // Otherwise, extra data or criteria resolvers were supplied; in
                          // that event, perform a more verbose staticcall to the zone.
                          bool success = _staticcall(
                              zone,
                              abi.encodeWithSelector(
                                  ZoneInterface.isValidOrderIncludingExtraData.selector,
                                  orderHash,
                                  msg.sender,
                                  advancedOrder,
                                  priorOrderHashes,
                                  criteriaResolvers
                              )
                          );
                          // Ensure call was successful and returned correct magic value.
                          _assertIsValidOrderStaticcallSuccess(success, orderHash);
                      }
                  }
              }
              /**
               * @dev Internal view function to ensure that a staticcall to `isValidOrder`
               *      or `isValidOrderIncludingExtraData` as part of validating a
               *      restricted order that was not submitted by the named offerer or zone
               *      was successful and returned the required magic value.
               *
               * @param success   A boolean indicating the status of the staticcall.
               * @param orderHash The order hash of the order in question.
               */
              function _assertIsValidOrderStaticcallSuccess(
                  bool success,
                  bytes32 orderHash
              ) internal view {
                  // If the call failed...
                  if (!success) {
                      // Revert and pass reason along if one was returned.
                      _revertWithReasonIfOneIsReturned();
                      // Otherwise, revert with a generic error message.
                      revert InvalidRestrictedOrder(orderHash);
                  }
                  // Ensure result was extracted and matches isValidOrder magic value.
                  if (_doesNotMatchMagic(ZoneInterface.isValidOrder.selector)) {
                      revert InvalidRestrictedOrder(orderHash);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title ZoneInteractionErrors
           * @author 0age
           * @notice ZoneInteractionErrors contains errors related to zone interaction.
           */
          interface ZoneInteractionErrors {
              /**
               * @dev Revert with an error when attempting to fill an order that specifies
               *      a restricted submitter as its order type when not submitted by
               *      either the offerer or the order's zone or approved as valid by the
               *      zone in question via a staticcall to `isValidOrder`.
               *
               * @param orderHash The order hash for the invalid restricted order.
               */
              error InvalidRestrictedOrder(bytes32 orderHash);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { ConduitInterface } from "../interfaces/ConduitInterface.sol";
          // prettier-ignore
          import {
              OrderType,
              ItemType,
              BasicOrderRouteType
          } from "./ConsiderationEnums.sol";
          // prettier-ignore
          import {
              AdditionalRecipient,
              BasicOrderParameters,
              OfferItem,
              ConsiderationItem,
              SpentItem,
              ReceivedItem
          } from "./ConsiderationStructs.sol";
          import { OrderValidator } from "./OrderValidator.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title BasicOrderFulfiller
           * @author 0age
           * @notice BasicOrderFulfiller contains functionality for fulfilling "basic"
           *         orders with minimal overhead. See documentation for details on what
           *         qualifies as a basic order.
           */
          contract BasicOrderFulfiller is OrderValidator {
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) OrderValidator(conduitController) {}
              /**
               * @dev Internal function to fulfill an order offering an ERC20, ERC721, or
               *      ERC1155 item by supplying Ether (or other native tokens), ERC20
               *      tokens, an ERC721 item, or an ERC1155 item as consideration. Six
               *      permutations are supported: Native token to ERC721, Native token to
               *      ERC1155, ERC20 to ERC721, ERC20 to ERC1155, ERC721 to ERC20, and
               *      ERC1155 to ERC20 (with native tokens supplied as msg.value). For an
               *      order to be eligible for fulfillment via this method, it must
               *      contain a single offer item (though that item may have a greater
               *      amount if the item is not an ERC721). An arbitrary number of
               *      "additional recipients" may also be supplied which will each receive
               *      native tokens or ERC20 items from the fulfiller as consideration.
               *      Refer to the documentation for a more comprehensive summary of how
               *      to utilize this method and what orders are compatible with it.
               *
               * @param parameters Additional information on the fulfilled order. Note
               *                   that the offerer and the fulfiller must first approve
               *                   this contract (or their chosen conduit if indicated)
               *                   before any tokens can be transferred. Also note that
               *                   contract recipients of ERC1155 consideration items must
               *                   implement `onERC1155Received` in order to receive those
               *                   items.
               *
               * @return A boolean indicating whether the order has been fulfilled.
               */
              function _validateAndFulfillBasicOrder(
                  BasicOrderParameters calldata parameters
              ) internal returns (bool) {
                  // Declare enums for order type & route to extract from basicOrderType.
                  BasicOrderRouteType route;
                  OrderType orderType;
                  // Declare additional recipient item type to derive from the route type.
                  ItemType additionalRecipientsItemType;
                  // Utilize assembly to extract the order type and the basic order route.
                  assembly {
                      // Read basicOrderType from calldata.
                      let basicOrderType := calldataload(BasicOrder_basicOrderType_cdPtr)
                      // Mask all but 2 least-significant bits to derive the order type.
                      orderType := and(basicOrderType, 3)
                      // Divide basicOrderType by four to derive the route.
                      route := shr(2, basicOrderType)
                      // If route > 1 additionalRecipient items are ERC20 (1) else Eth (0)
                      additionalRecipientsItemType := gt(route, 1)
                  }
                  {
                      // Declare temporary variable for enforcing payable status.
                      bool correctPayableStatus;
                      // Utilize assembly to compare the route to the callvalue.
                      assembly {
                          // route 0 and 1 are payable, otherwise route is not payable.
                          correctPayableStatus := eq(
                              additionalRecipientsItemType,
                              iszero(callvalue())
                          )
                      }
                      // Revert if msg.value has not been supplied as part of payable
                      // routes or has been supplied as part of non-payable routes.
                      if (!correctPayableStatus) {
                          revert InvalidMsgValue(msg.value);
                      }
                  }
                  // Declare more arguments that will be derived from route and calldata.
                  address additionalRecipientsToken;
                  ItemType offeredItemType;
                  bool offerTypeIsAdditionalRecipientsType;
                  // Declare scope for received item type to manage stack pressure.
                  {
                      ItemType receivedItemType;
                      // Utilize assembly to retrieve function arguments and cast types.
                      assembly {
                          // Check if offered item type == additional recipient item type.
                          offerTypeIsAdditionalRecipientsType := gt(route, 3)
                          // If route > 3 additionalRecipientsToken is at 0xc4 else 0x24.
                          additionalRecipientsToken := calldataload(
                              add(
                                  BasicOrder_considerationToken_cdPtr,
                                  mul(
                                      offerTypeIsAdditionalRecipientsType,
                                      BasicOrder_common_params_size
                                  )
                              )
                          )
                          // If route > 2, receivedItemType is route - 2. If route is 2,
                          // the receivedItemType is ERC20 (1). Otherwise, it is Eth (0).
                          receivedItemType := add(
                              mul(sub(route, 2), gt(route, 2)),
                              eq(route, 2)
                          )
                          // If route > 3, offeredItemType is ERC20 (1). Route is 2 or 3,
                          // offeredItemType = route. Route is 0 or 1, it is route + 2.
                          offeredItemType := sub(
                              add(route, mul(iszero(additionalRecipientsItemType), 2)),
                              mul(
                                  offerTypeIsAdditionalRecipientsType,
                                  add(receivedItemType, 1)
                              )
                          )
                      }
                      // Derive & validate order using parameters and update order status.
                      _prepareBasicFulfillmentFromCalldata(
                          parameters,
                          orderType,
                          receivedItemType,
                          additionalRecipientsItemType,
                          additionalRecipientsToken,
                          offeredItemType
                      );
                  }
                  // Declare conduitKey argument used by transfer functions.
                  bytes32 conduitKey;
                  // Utilize assembly to derive conduit (if relevant) based on route.
                  assembly {
                      // use offerer conduit for routes 0-3, fulfiller conduit otherwise.
                      conduitKey := calldataload(
                          add(
                              BasicOrder_offererConduit_cdPtr,
                              mul(offerTypeIsAdditionalRecipientsType, OneWord)
                          )
                      )
                  }
                  // Transfer tokens based on the route.
                  if (additionalRecipientsItemType == ItemType.NATIVE) {
                      // Ensure neither the token nor the identifier parameters are set.
                      if (
                          (uint160(parameters.considerationToken) |
                              parameters.considerationIdentifier) != 0
                      ) {
                          revert UnusedItemParameters();
                      }
                      // Transfer the ERC721 or ERC1155 item, bypassing the accumulator.
                      _transferIndividual721Or1155Item(
                          offeredItemType,
                          parameters.offerToken,
                          parameters.offerer,
                          msg.sender,
                          parameters.offerIdentifier,
                          parameters.offerAmount,
                          conduitKey
                      );
                      // Transfer native to recipients, return excess to caller & wrap up.
                      _transferEthAndFinalize(
                          parameters.considerationAmount,
                          parameters.offerer,
                          parameters.additionalRecipients
                      );
                  } else {
                      // Initialize an accumulator array. From this point forward, no new
                      // memory regions can be safely allocated until the accumulator is
                      // no longer being utilized, as the accumulator operates in an
                      // open-ended fashion from this memory pointer; existing memory may
                      // still be accessed and modified, however.
                      bytes memory accumulator = new bytes(AccumulatorDisarmed);
                      // Choose transfer method for ERC721 or ERC1155 item based on route.
                      if (route == BasicOrderRouteType.ERC20_TO_ERC721) {
                          // Transfer ERC721 to caller using offerer's conduit preference.
                          _transferERC721(
                              parameters.offerToken,
                              parameters.offerer,
                              msg.sender,
                              parameters.offerIdentifier,
                              parameters.offerAmount,
                              conduitKey,
                              accumulator
                          );
                      } else if (route == BasicOrderRouteType.ERC20_TO_ERC1155) {
                          // Transfer ERC1155 to caller with offerer's conduit preference.
                          _transferERC1155(
                              parameters.offerToken,
                              parameters.offerer,
                              msg.sender,
                              parameters.offerIdentifier,
                              parameters.offerAmount,
                              conduitKey,
                              accumulator
                          );
                      } else if (route == BasicOrderRouteType.ERC721_TO_ERC20) {
                          // Transfer ERC721 to offerer using caller's conduit preference.
                          _transferERC721(
                              parameters.considerationToken,
                              msg.sender,
                              parameters.offerer,
                              parameters.considerationIdentifier,
                              parameters.considerationAmount,
                              conduitKey,
                              accumulator
                          );
                      } else {
                          // route == BasicOrderRouteType.ERC1155_TO_ERC20
                          // Transfer ERC1155 to offerer with caller's conduit preference.
                          _transferERC1155(
                              parameters.considerationToken,
                              msg.sender,
                              parameters.offerer,
                              parameters.considerationIdentifier,
                              parameters.considerationAmount,
                              conduitKey,
                              accumulator
                          );
                      }
                      // Transfer ERC20 tokens to all recipients and wrap up.
                      _transferERC20AndFinalize(
                          parameters.offerer,
                          parameters,
                          offerTypeIsAdditionalRecipientsType,
                          accumulator
                      );
                      // Trigger any remaining accumulated transfers via call to conduit.
                      _triggerIfArmed(accumulator);
                  }
                  // Clear the reentrancy guard.
                  _clearReentrancyGuard();
                  return true;
              }
              /**
               * @dev Internal function to prepare fulfillment of a basic order with
               *      manual calldata and memory access. This calculates the order hash,
               *      emits an OrderFulfilled event, and asserts basic order validity.
               *      Note that calldata offsets must be validated as this function
               *      accesses constant calldata pointers for dynamic types that match
               *      default ABI encoding, but valid ABI encoding can use arbitrary
               *      offsets. Checking that the offsets were produced by default encoding
               *      will ensure that other functions using Solidity's calldata accessors
               *      (which calculate pointers from the stored offsets) are reading the
               *      same data as the order hash is derived from. Also note that This
               *      function accesses memory directly. It does not clear the expanded
               *      memory regions used, nor does it update the free memory pointer, so
               *      other direct memory access must not assume that unused memory is
               *      empty.
               *
               * @param parameters                   The parameters of the basic order.
               * @param orderType                    The order type.
               * @param receivedItemType             The item type of the initial
               *                                     consideration item on the order.
               * @param additionalRecipientsItemType The item type of any additional
               *                                     consideration item on the order.
               * @param additionalRecipientsToken    The ERC20 token contract address (if
               *                                     applicable) for any additional
               *                                     consideration item on the order.
               * @param offeredItemType              The item type of the offered item on
               *                                     the order.
               */
              function _prepareBasicFulfillmentFromCalldata(
                  BasicOrderParameters calldata parameters,
                  OrderType orderType,
                  ItemType receivedItemType,
                  ItemType additionalRecipientsItemType,
                  address additionalRecipientsToken,
                  ItemType offeredItemType
              ) internal {
                  // Ensure this function cannot be triggered during a reentrant call.
                  _setReentrancyGuard();
                  // Ensure current timestamp falls between order start time and end time.
                  _verifyTime(parameters.startTime, parameters.endTime, true);
                  // Verify that calldata offsets for all dynamic types were produced by
                  // default encoding. This ensures that the constants we use for calldata
                  // pointers to dynamic types are the same as those calculated by
                  // Solidity using their offsets. Also verify that the basic order type
                  // is within range.
                  _assertValidBasicOrderParameters();
                  // Ensure supplied consideration array length is not less than original.
                  _assertConsiderationLengthIsNotLessThanOriginalConsiderationLength(
                      parameters.additionalRecipients.length,
                      parameters.totalOriginalAdditionalRecipients
                  );
                  // Declare stack element for the order hash.
                  bytes32 orderHash;
                  {
                      /**
                       * First, handle consideration items. Memory Layout:
                       *  0x60: final hash of the array of consideration item hashes
                       *  0x80-0x160: reused space for EIP712 hashing of each item
                       *   - 0x80: ConsiderationItem EIP-712 typehash (constant)
                       *   - 0xa0: itemType
                       *   - 0xc0: token
                       *   - 0xe0: identifier
                       *   - 0x100: startAmount
                       *   - 0x120: endAmount
                       *   - 0x140: recipient
                       *  0x160-END_ARR: array of consideration item hashes
                       *   - 0x160: primary consideration item EIP712 hash
                       *   - 0x180-END_ARR: additional recipient item EIP712 hashes
                       *  END_ARR: beginning of data for OrderFulfilled event
                       *   - END_ARR + 0x120: length of ReceivedItem array
                       *   - END_ARR + 0x140: beginning of data for first ReceivedItem
                       * (Note: END_ARR = 0x180 + RECIPIENTS_LENGTH * 0x20)
                       */
                      // Load consideration item typehash from runtime and place on stack.
                      bytes32 typeHash = _CONSIDERATION_ITEM_TYPEHASH;
                      // Utilize assembly to enable reuse of memory regions and use
                      // constant pointers when possible.
                      assembly {
                          /*
                           * 1. Calculate the EIP712 ConsiderationItem hash for the
                           * primary consideration item of the basic order.
                           */
                          // Write ConsiderationItem type hash and item type to memory.
                          mstore(BasicOrder_considerationItem_typeHash_ptr, typeHash)
                          mstore(
                              BasicOrder_considerationItem_itemType_ptr,
                              receivedItemType
                          )
                          // Copy calldata region with (token, identifier, amount) from
                          // BasicOrderParameters to ConsiderationItem. The
                          // considerationAmount is written to startAmount and endAmount
                          // as basic orders do not have dynamic amounts.
                          calldatacopy(
                              BasicOrder_considerationItem_token_ptr,
                              BasicOrder_considerationToken_cdPtr,
                              ThreeWords
                          )
                          // Copy calldata region with considerationAmount and offerer
                          // from BasicOrderParameters to endAmount and recipient in
                          // ConsiderationItem.
                          calldatacopy(
                              BasicOrder_considerationItem_endAmount_ptr,
                              BasicOrder_considerationAmount_cdPtr,
                              TwoWords
                          )
                          // Calculate EIP712 ConsiderationItem hash and store it in the
                          // array of EIP712 consideration hashes.
                          mstore(
                              BasicOrder_considerationHashesArray_ptr,
                              keccak256(
                                  BasicOrder_considerationItem_typeHash_ptr,
                                  EIP712_ConsiderationItem_size
                              )
                          )
                          /*
                           * 2. Write a ReceivedItem struct for the primary consideration
                           * item to the consideration array in OrderFulfilled.
                           */
                          // Get the length of the additional recipients array.
                          let totalAdditionalRecipients := calldataload(
                              BasicOrder_additionalRecipients_length_cdPtr
                          )
                          // Calculate pointer to length of OrderFulfilled consideration
                          // array.
                          let eventConsiderationArrPtr := add(
                              OrderFulfilled_consideration_length_baseOffset,
                              mul(totalAdditionalRecipients, OneWord)
                          )
                          // Set the length of the consideration array to the number of
                          // additional recipients, plus one for the primary consideration
                          // item.
                          mstore(
                              eventConsiderationArrPtr,
                              add(
                                  calldataload(
                                      BasicOrder_additionalRecipients_length_cdPtr
                                  ),
                                  1
                              )
                          )
                          // Overwrite the consideration array pointer so it points to the
                          // body of the first element
                          eventConsiderationArrPtr := add(
                              eventConsiderationArrPtr,
                              OneWord
                          )
                          // Set itemType at start of the ReceivedItem memory region.
                          mstore(eventConsiderationArrPtr, receivedItemType)
                          // Copy calldata region (token, identifier, amount & recipient)
                          // from BasicOrderParameters to ReceivedItem memory.
                          calldatacopy(
                              add(eventConsiderationArrPtr, Common_token_offset),
                              BasicOrder_considerationToken_cdPtr,
                              FourWords
                          )
                          /*
                           * 3. Calculate EIP712 ConsiderationItem hashes for original
                           * additional recipients and add a ReceivedItem for each to the
                           * consideration array in the OrderFulfilled event. The original
                           * additional recipients are all the considerations signed by
                           * the offerer aside from the primary consideration of the
                           * order. Uses memory region from 0x80-0x160 as a buffer for
                           * calculating EIP712 ConsiderationItem hashes.
                           */
                          // Put pointer to consideration hashes array on the stack.
                          // This will be updated as each additional recipient is hashed
                          let
                              considerationHashesPtr
                          := BasicOrder_considerationHashesArray_ptr
                          // Write item type, token, & identifier for additional recipient
                          // to memory region for hashing EIP712 ConsiderationItem; these
                          // values will be reused for each recipient.
                          mstore(
                              BasicOrder_considerationItem_itemType_ptr,
                              additionalRecipientsItemType
                          )
                          mstore(
                              BasicOrder_considerationItem_token_ptr,
                              additionalRecipientsToken
                          )
                          mstore(BasicOrder_considerationItem_identifier_ptr, 0)
                          // Read length of the additionalRecipients array from calldata
                          // and iterate.
                          totalAdditionalRecipients := calldataload(
                              BasicOrder_totalOriginalAdditionalRecipients_cdPtr
                          )
                          let i := 0
                          // prettier-ignore
                          for {} lt(i, totalAdditionalRecipients) {
                              i := add(i, 1)
                          } {
                              /*
                               * Calculate EIP712 ConsiderationItem hash for recipient.
                               */
                              // Retrieve calldata pointer for additional recipient.
                              let additionalRecipientCdPtr := add(
                                  BasicOrder_additionalRecipients_data_cdPtr,
                                  mul(AdditionalRecipients_size, i)
                              )
                              // Copy startAmount from calldata to the ConsiderationItem
                              // struct.
                              calldatacopy(
                                  BasicOrder_considerationItem_startAmount_ptr,
                                  additionalRecipientCdPtr,
                                  OneWord
                              )
                              // Copy endAmount and recipient from calldata to the
                              // ConsiderationItem struct.
                              calldatacopy(
                                  BasicOrder_considerationItem_endAmount_ptr,
                                  additionalRecipientCdPtr,
                                  AdditionalRecipients_size
                              )
                              // Add 1 word to the pointer as part of each loop to reduce
                              // operations needed to get local offset into the array.
                              considerationHashesPtr := add(
                                  considerationHashesPtr,
                                  OneWord
                              )
                              // Calculate EIP712 ConsiderationItem hash and store it in
                              // the array of consideration hashes.
                              mstore(
                                  considerationHashesPtr,
                                  keccak256(
                                      BasicOrder_considerationItem_typeHash_ptr,
                                      EIP712_ConsiderationItem_size
                                  )
                              )
                              /*
                               * Write ReceivedItem to OrderFulfilled data.
                               */
                              // At this point, eventConsiderationArrPtr points to the
                              // beginning of the ReceivedItem struct of the previous
                              // element in the array. Increase it by the size of the
                              // struct to arrive at the pointer for the current element.
                              eventConsiderationArrPtr := add(
                                  eventConsiderationArrPtr,
                                  ReceivedItem_size
                              )
                              // Write itemType to the ReceivedItem struct.
                              mstore(
                                  eventConsiderationArrPtr,
                                  additionalRecipientsItemType
                              )
                              // Write token to the next word of the ReceivedItem struct.
                              mstore(
                                  add(eventConsiderationArrPtr, OneWord),
                                  additionalRecipientsToken
                              )
                              // Copy endAmount & recipient words to ReceivedItem struct.
                              calldatacopy(
                                  add(
                                      eventConsiderationArrPtr,
                                      ReceivedItem_amount_offset
                                  ),
                                  additionalRecipientCdPtr,
                                  TwoWords
                              )
                          }
                          /*
                           * 4. Hash packed array of ConsiderationItem EIP712 hashes:
                           *   `keccak256(abi.encodePacked(receivedItemHashes))`
                           * Note that it is set at 0x60 — all other memory begins at
                           * 0x80. 0x60 is the "zero slot" and will be restored at the end
                           * of the assembly section and before required by the compiler.
                           */
                          mstore(
                              receivedItemsHash_ptr,
                              keccak256(
                                  BasicOrder_considerationHashesArray_ptr,
                                  mul(add(totalAdditionalRecipients, 1), OneWord)
                              )
                          )
                          /*
                           * 5. Add a ReceivedItem for each tip to the consideration array
                           * in the OrderFulfilled event. The tips are all the
                           * consideration items that were not signed by the offerer and
                           * were provided by the fulfiller.
                           */
                          // Overwrite length to length of the additionalRecipients array.
                          totalAdditionalRecipients := calldataload(
                              BasicOrder_additionalRecipients_length_cdPtr
                          )
                          // prettier-ignore
                          for {} lt(i, totalAdditionalRecipients) {
                              i := add(i, 1)
                          } {
                              // Retrieve calldata pointer for additional recipient.
                              let additionalRecipientCdPtr := add(
                                  BasicOrder_additionalRecipients_data_cdPtr,
                                  mul(AdditionalRecipients_size, i)
                              )
                              // At this point, eventConsiderationArrPtr points to the
                              // beginning of the ReceivedItem struct of the previous
                              // element in the array. Increase it by the size of the
                              // struct to arrive at the pointer for the current element.
                              eventConsiderationArrPtr := add(
                                  eventConsiderationArrPtr,
                                  ReceivedItem_size
                              )
                              // Write itemType to the ReceivedItem struct.
                              mstore(
                                  eventConsiderationArrPtr,
                                  additionalRecipientsItemType
                              )
                              // Write token to the next word of the ReceivedItem struct.
                              mstore(
                                  add(eventConsiderationArrPtr, OneWord),
                                  additionalRecipientsToken
                              )
                              // Copy endAmount & recipient words to ReceivedItem struct.
                              calldatacopy(
                                  add(
                                      eventConsiderationArrPtr,
                                      ReceivedItem_amount_offset
                                  ),
                                  additionalRecipientCdPtr,
                                  TwoWords
                              )
                          }
                      }
                  }
                  {
                      /**
                       * Next, handle offered items. Memory Layout:
                       *  EIP712 data for OfferItem
                       *   - 0x80:  OfferItem EIP-712 typehash (constant)
                       *   - 0xa0:  itemType
                       *   - 0xc0:  token
                       *   - 0xe0:  identifier (reused for offeredItemsHash)
                       *   - 0x100: startAmount
                       *   - 0x120: endAmount
                       */
                      // Place offer item typehash on the stack.
                      bytes32 typeHash = _OFFER_ITEM_TYPEHASH;
                      // Utilize assembly to enable reuse of memory regions when possible.
                      assembly {
                          /*
                           * 1. Calculate OfferItem EIP712 hash
                           */
                          // Write the OfferItem typeHash to memory.
                          mstore(BasicOrder_offerItem_typeHash_ptr, typeHash)
                          // Write the OfferItem item type to memory.
                          mstore(BasicOrder_offerItem_itemType_ptr, offeredItemType)
                          // Copy calldata region with (offerToken, offerIdentifier,
                          // offerAmount) from OrderParameters to (token, identifier,
                          // startAmount) in OfferItem struct. The offerAmount is written
                          // to startAmount and endAmount as basic orders do not have
                          // dynamic amounts.
                          calldatacopy(
                              BasicOrder_offerItem_token_ptr,
                              BasicOrder_offerToken_cdPtr,
                              ThreeWords
                          )
                          // Copy offerAmount from calldata to endAmount in OfferItem
                          // struct.
                          calldatacopy(
                              BasicOrder_offerItem_endAmount_ptr,
                              BasicOrder_offerAmount_cdPtr,
                              OneWord
                          )
                          // Compute EIP712 OfferItem hash, write result to scratch space:
                          //   `keccak256(abi.encode(offeredItem))`
                          mstore(
                              0,
                              keccak256(
                                  BasicOrder_offerItem_typeHash_ptr,
                                  EIP712_OfferItem_size
                              )
                          )
                          /*
                           * 2. Calculate hash of array of EIP712 hashes and write the
                           * result to the corresponding OfferItem struct:
                           *   `keccak256(abi.encodePacked(offerItemHashes))`
                           */
                          mstore(BasicOrder_order_offerHashes_ptr, keccak256(0, OneWord))
                          /*
                           * 3. Write SpentItem to offer array in OrderFulfilled event.
                           */
                          let eventConsiderationArrPtr := add(
                              OrderFulfilled_offer_length_baseOffset,
                              mul(
                                  calldataload(
                                      BasicOrder_additionalRecipients_length_cdPtr
                                  ),
                                  OneWord
                              )
                          )
                          // Set a length of 1 for the offer array.
                          mstore(eventConsiderationArrPtr, 1)
                          // Write itemType to the SpentItem struct.
                          mstore(add(eventConsiderationArrPtr, OneWord), offeredItemType)
                          // Copy calldata region with (offerToken, offerIdentifier,
                          // offerAmount) from OrderParameters to (token, identifier,
                          // amount) in SpentItem struct.
                          calldatacopy(
                              add(eventConsiderationArrPtr, AdditionalRecipients_size),
                              BasicOrder_offerToken_cdPtr,
                              ThreeWords
                          )
                      }
                  }
                  {
                      /**
                       * Once consideration items and offer items have been handled,
                       * derive the final order hash. Memory Layout:
                       *  0x80-0x1c0: EIP712 data for order
                       *   - 0x80:   Order EIP-712 typehash (constant)
                       *   - 0xa0:   orderParameters.offerer
                       *   - 0xc0:   orderParameters.zone
                       *   - 0xe0:   keccak256(abi.encodePacked(offerHashes))
                       *   - 0x100:  keccak256(abi.encodePacked(considerationHashes))
                       *   - 0x120:  orderParameters.basicOrderType (% 4 = orderType)
                       *   - 0x140:  orderParameters.startTime
                       *   - 0x160:  orderParameters.endTime
                       *   - 0x180:  orderParameters.zoneHash
                       *   - 0x1a0:  orderParameters.salt
                       *   - 0x1c0:  orderParameters.conduitKey
                       *   - 0x1e0:  _counters[orderParameters.offerer] (from storage)
                       */
                      // Read the offerer from calldata and place on the stack.
                      address offerer;
                      assembly {
                          offerer := calldataload(BasicOrder_offerer_cdPtr)
                      }
                      // Read offerer's current counter from storage and place on stack.
                      uint256 counter = _getCounter(offerer);
                      // Load order typehash from runtime code and place on stack.
                      bytes32 typeHash = _ORDER_TYPEHASH;
                      assembly {
                          // Set the OrderItem typeHash in memory.
                          mstore(BasicOrder_order_typeHash_ptr, typeHash)
                          // Copy offerer and zone from OrderParameters in calldata to the
                          // Order struct.
                          calldatacopy(
                              BasicOrder_order_offerer_ptr,
                              BasicOrder_offerer_cdPtr,
                              TwoWords
                          )
                          // Copy receivedItemsHash from zero slot to the Order struct.
                          mstore(
                              BasicOrder_order_considerationHashes_ptr,
                              mload(receivedItemsHash_ptr)
                          )
                          // Write the supplied orderType to the Order struct.
                          mstore(BasicOrder_order_orderType_ptr, orderType)
                          // Copy startTime, endTime, zoneHash, salt & conduit from
                          // calldata to the Order struct.
                          calldatacopy(
                              BasicOrder_order_startTime_ptr,
                              BasicOrder_startTime_cdPtr,
                              FiveWords
                          )
                          // Write offerer's counter, retrieved from storage, to struct.
                          mstore(BasicOrder_order_counter_ptr, counter)
                          // Compute the EIP712 Order hash.
                          orderHash := keccak256(
                              BasicOrder_order_typeHash_ptr,
                              EIP712_Order_size
                          )
                      }
                  }
                  assembly {
                      /**
                       * After the order hash has been derived, emit OrderFulfilled event:
                       *   event OrderFulfilled(
                       *     bytes32 orderHash,
                       *     address indexed offerer,
                       *     address indexed zone,
                       *     address fulfiller,
                       *     SpentItem[] offer,
                       *       > (itemType, token, id, amount)
                       *     ReceivedItem[] consideration
                       *       > (itemType, token, id, amount, recipient)
                       *   )
                       * topic0 - OrderFulfilled event signature
                       * topic1 - offerer
                       * topic2 - zone
                       * data:
                       *  - 0x00: orderHash
                       *  - 0x20: fulfiller
                       *  - 0x40: offer arr ptr (0x80)
                       *  - 0x60: consideration arr ptr (0x120)
                       *  - 0x80: offer arr len (1)
                       *  - 0xa0: offer.itemType
                       *  - 0xc0: offer.token
                       *  - 0xe0: offer.identifier
                       *  - 0x100: offer.amount
                       *  - 0x120: 1 + recipients.length
                       *  - 0x140: recipient 0
                       */
                      // Derive pointer to start of OrderFulfilled event data
                      let eventDataPtr := add(
                          OrderFulfilled_baseOffset,
                          mul(
                              calldataload(BasicOrder_additionalRecipients_length_cdPtr),
                              OneWord
                          )
                      )
                      // Write the order hash to the head of the event's data region.
                      mstore(eventDataPtr, orderHash)
                      // Write the fulfiller (i.e. the caller) next for receiver argument.
                      mstore(add(eventDataPtr, OrderFulfilled_fulfiller_offset), caller())
                      // Write the SpentItem and ReceivedItem array offsets (constants).
                      mstore(
                          // SpentItem array offset
                          add(eventDataPtr, OrderFulfilled_offer_head_offset),
                          OrderFulfilled_offer_body_offset
                      )
                      mstore(
                          // ReceivedItem array offset
                          add(eventDataPtr, OrderFulfilled_consideration_head_offset),
                          OrderFulfilled_consideration_body_offset
                      )
                      // Derive total data size including SpentItem and ReceivedItem data.
                      // SpentItem portion is already included in the baseSize constant,
                      // as there can only be one element in the array.
                      let dataSize := add(
                          OrderFulfilled_baseSize,
                          mul(
                              calldataload(BasicOrder_additionalRecipients_length_cdPtr),
                              ReceivedItem_size
                          )
                      )
                      // Emit OrderFulfilled log with three topics (the event signature
                      // as well as the two indexed arguments, the offerer and the zone).
                      log3(
                          // Supply the pointer for event data in memory.
                          eventDataPtr,
                          // Supply the size of event data in memory.
                          dataSize,
                          // Supply the OrderFulfilled event signature.
                          OrderFulfilled_selector,
                          // Supply the first topic (the offerer).
                          calldataload(BasicOrder_offerer_cdPtr),
                          // Supply the second topic (the zone).
                          calldataload(BasicOrder_zone_cdPtr)
                      )
                      // Restore the zero slot.
                      mstore(ZeroSlot, 0)
                  }
                  // Determine whether order is restricted and, if so, that it is valid.
                  _assertRestrictedBasicOrderValidity(
                      orderHash,
                      parameters.zoneHash,
                      orderType,
                      parameters.offerer,
                      parameters.zone
                  );
                  // Verify and update the status of the derived order.
                  _validateBasicOrderAndUpdateStatus(
                      orderHash,
                      parameters.offerer,
                      parameters.signature
                  );
              }
              /**
               * @dev Internal function to transfer Ether (or other native tokens) to a
               *      given recipient as part of basic order fulfillment. Note that
               *      conduits are not utilized for native tokens as the transferred
               *      amount must be provided as msg.value.
               *
               * @param amount               The amount to transfer.
               * @param to                   The recipient of the native token transfer.
               * @param additionalRecipients The additional recipients of the order.
               */
              function _transferEthAndFinalize(
                  uint256 amount,
                  address payable to,
                  AdditionalRecipient[] calldata additionalRecipients
              ) internal {
                  // Put ether value supplied by the caller on the stack.
                  uint256 etherRemaining = msg.value;
                  // Retrieve total number of additional recipients and place on stack.
                  uint256 totalAdditionalRecipients = additionalRecipients.length;
                  // Skip overflow check as for loop is indexed starting at zero.
                  unchecked {
                      // Iterate over each additional recipient.
                      for (uint256 i = 0; i < totalAdditionalRecipients; ++i) {
                          // Retrieve the additional recipient.
                          AdditionalRecipient calldata additionalRecipient = (
                              additionalRecipients[i]
                          );
                          // Read ether amount to transfer to recipient & place on stack.
                          uint256 additionalRecipientAmount = additionalRecipient.amount;
                          // Ensure that sufficient Ether is available.
                          if (additionalRecipientAmount > etherRemaining) {
                              revert InsufficientEtherSupplied();
                          }
                          // Transfer Ether to the additional recipient.
                          _transferEth(
                              additionalRecipient.recipient,
                              additionalRecipientAmount
                          );
                          // Reduce ether value available. Skip underflow check as
                          // subtracted value is confirmed above as less than remaining.
                          etherRemaining -= additionalRecipientAmount;
                      }
                  }
                  // Ensure that sufficient Ether is still available.
                  if (amount > etherRemaining) {
                      revert InsufficientEtherSupplied();
                  }
                  // Transfer Ether to the offerer.
                  _transferEth(to, amount);
                  // If any Ether remains after transfers, return it to the caller.
                  if (etherRemaining > amount) {
                      // Skip underflow check as etherRemaining > amount.
                      unchecked {
                          // Transfer remaining Ether to the caller.
                          _transferEth(payable(msg.sender), etherRemaining - amount);
                      }
                  }
              }
              /**
               * @dev Internal function to transfer ERC20 tokens to a given recipient as
               *      part of basic order fulfillment.
               *
               * @param offerer     The offerer of the fulfiller order.
               * @param parameters  The basic order parameters.
               * @param fromOfferer A boolean indicating whether to decrement amount from
               *                    the offered amount.
               * @param accumulator An open-ended array that collects transfers to execute
               *                    against a given conduit in a single call.
               */
              function _transferERC20AndFinalize(
                  address offerer,
                  BasicOrderParameters calldata parameters,
                  bool fromOfferer,
                  bytes memory accumulator
              ) internal {
                  // Declare from and to variables determined by fromOfferer value.
                  address from;
                  address to;
                  // Declare token and amount variables determined by fromOfferer value.
                  address token;
                  uint256 amount;
                  // Declare and check identifier variable within an isolated scope.
                  {
                      // Declare identifier variable determined by fromOfferer value.
                      uint256 identifier;
                      // Set ERC20 token transfer variables based on fromOfferer boolean.
                      if (fromOfferer) {
                          // Use offerer as from value and msg.sender as to value.
                          from = offerer;
                          to = msg.sender;
                          // Use offer token and related values if token is from offerer.
                          token = parameters.offerToken;
                          identifier = parameters.offerIdentifier;
                          amount = parameters.offerAmount;
                      } else {
                          // Use msg.sender as from value and offerer as to value.
                          from = msg.sender;
                          to = offerer;
                          // Otherwise, use consideration token and related values.
                          token = parameters.considerationToken;
                          identifier = parameters.considerationIdentifier;
                          amount = parameters.considerationAmount;
                      }
                      // Ensure that no identifier is supplied.
                      if (identifier != 0) {
                          revert UnusedItemParameters();
                      }
                  }
                  // Determine the appropriate conduit to utilize.
                  bytes32 conduitKey;
                  // Utilize assembly to derive conduit (if relevant) based on route.
                  assembly {
                      // Use offerer conduit if fromOfferer, fulfiller conduit otherwise.
                      conduitKey := calldataload(
                          sub(
                              BasicOrder_fulfillerConduit_cdPtr,
                              mul(fromOfferer, OneWord)
                          )
                      )
                  }
                  // Retrieve total number of additional recipients and place on stack.
                  uint256 totalAdditionalRecipients = (
                      parameters.additionalRecipients.length
                  );
                  // Iterate over each additional recipient.
                  for (uint256 i = 0; i < totalAdditionalRecipients; ) {
                      // Retrieve the additional recipient.
                      AdditionalRecipient calldata additionalRecipient = (
                          parameters.additionalRecipients[i]
                      );
                      uint256 additionalRecipientAmount = additionalRecipient.amount;
                      // Decrement the amount to transfer to fulfiller if indicated.
                      if (fromOfferer) {
                          amount -= additionalRecipientAmount;
                      }
                      // Transfer ERC20 tokens to additional recipient given approval.
                      _transferERC20(
                          token,
                          from,
                          additionalRecipient.recipient,
                          additionalRecipientAmount,
                          conduitKey,
                          accumulator
                      );
                      // Skip overflow check as for loop is indexed starting at zero.
                      unchecked {
                          ++i;
                      }
                  }
                  // Transfer ERC20 token amount (from account must have proper approval).
                  _transferERC20(token, from, to, amount, conduitKey, accumulator);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { OrderType } from "./ConsiderationEnums.sol";
          // prettier-ignore
          import {
              OrderParameters,
              Order,
              AdvancedOrder,
              OrderComponents,
              OrderStatus,
              CriteriaResolver
          } from "./ConsiderationStructs.sol";
          import "./ConsiderationConstants.sol";
          import { Executor } from "./Executor.sol";
          import { ZoneInteraction } from "./ZoneInteraction.sol";
          /**
           * @title OrderValidator
           * @author 0age
           * @notice OrderValidator contains functionality related to validating orders
           *         and updating their status.
           */
          contract OrderValidator is Executor, ZoneInteraction {
              // Track status of each order (validated, cancelled, and fraction filled).
              mapping(bytes32 => OrderStatus) private _orderStatus;
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) Executor(conduitController) {}
              /**
               * @dev Internal function to verify and update the status of a basic order.
               *
               * @param orderHash The hash of the order.
               * @param offerer   The offerer of the order.
               * @param signature A signature from the offerer indicating that the order
               *                  has been approved.
               */
              function _validateBasicOrderAndUpdateStatus(
                  bytes32 orderHash,
                  address offerer,
                  bytes memory signature
              ) internal {
                  // Retrieve the order status for the given order hash.
                  OrderStatus storage orderStatus = _orderStatus[orderHash];
                  // Ensure order is fillable and is not cancelled.
                  _verifyOrderStatus(
                      orderHash,
                      orderStatus,
                      true, // Only allow unused orders when fulfilling basic orders.
                      true // Signifies to revert if the order is invalid.
                  );
                  // If the order is not already validated, verify the supplied signature.
                  if (!orderStatus.isValidated) {
                      _verifySignature(offerer, orderHash, signature);
                  }
                  // Update order status as fully filled, packing struct values.
                  orderStatus.isValidated = true;
                  orderStatus.isCancelled = false;
                  orderStatus.numerator = 1;
                  orderStatus.denominator = 1;
              }
              /**
               * @dev Internal function to validate an order, determine what portion to
               *      fill, and update its status. The desired fill amount is supplied as
               *      a fraction, as is the returned amount to fill.
               *
               * @param advancedOrder     The order to fulfill as well as the fraction to
               *                          fill. Note that all offer and consideration
               *                          amounts must divide with no remainder in order
               *                          for a partial fill to be valid.
               * @param criteriaResolvers An array where each element contains a reference
               *                          to a specific offer or consideration, a token
               *                          identifier, and a proof that the supplied token
               *                          identifier is contained in the order's merkle
               *                          root. Note that a criteria of zero indicates
               *                          that any (transferable) token identifier is
               *                          valid and that no proof needs to be supplied.
               * @param revertOnInvalid   A boolean indicating whether to revert if the
               *                          order is invalid due to the time or status.
               * @param priorOrderHashes  The order hashes of each order supplied prior to
               *                          the current order as part of a "match" variety
               *                          of order fulfillment (e.g. this array will be
               *                          empty for single or "fulfill available").
               *
               * @return orderHash      The order hash.
               * @return newNumerator   A value indicating the portion of the order that
               *                        will be filled.
               * @return newDenominator A value indicating the total size of the order.
               */
              function _validateOrderAndUpdateStatus(
                  AdvancedOrder memory advancedOrder,
                  CriteriaResolver[] memory criteriaResolvers,
                  bool revertOnInvalid,
                  bytes32[] memory priorOrderHashes
              )
                  internal
                  returns (
                      bytes32 orderHash,
                      uint256 newNumerator,
                      uint256 newDenominator
                  )
              {
                  // Retrieve the parameters for the order.
                  OrderParameters memory orderParameters = advancedOrder.parameters;
                  // Ensure current timestamp falls between order start time and end time.
                  if (
                      !_verifyTime(
                          orderParameters.startTime,
                          orderParameters.endTime,
                          revertOnInvalid
                      )
                  ) {
                      // Assuming an invalid time and no revert, return zeroed out values.
                      return (bytes32(0), 0, 0);
                  }
                  // Read numerator and denominator from memory and place on the stack.
                  uint256 numerator = uint256(advancedOrder.numerator);
                  uint256 denominator = uint256(advancedOrder.denominator);
                  // Ensure that the supplied numerator and denominator are valid.
                  if (numerator > denominator || numerator == 0) {
                      revert BadFraction();
                  }
                  // If attempting partial fill (n < d) check order type & ensure support.
                  if (
                      numerator < denominator &&
                      _doesNotSupportPartialFills(orderParameters.orderType)
                  ) {
                      // Revert if partial fill was attempted on an unsupported order.
                      revert PartialFillsNotEnabledForOrder();
                  }
                  // Retrieve current counter & use it w/ parameters to derive order hash.
                  orderHash = _assertConsiderationLengthAndGetOrderHash(orderParameters);
                  // Ensure restricted orders have a valid submitter or pass a zone check.
                  _assertRestrictedAdvancedOrderValidity(
                      advancedOrder,
                      criteriaResolvers,
                      priorOrderHashes,
                      orderHash,
                      orderParameters.zoneHash,
                      orderParameters.orderType,
                      orderParameters.offerer,
                      orderParameters.zone
                  );
                  // Retrieve the order status using the derived order hash.
                  OrderStatus storage orderStatus = _orderStatus[orderHash];
                  // Ensure order is fillable and is not cancelled.
                  if (
                      !_verifyOrderStatus(
                          orderHash,
                          orderStatus,
                          false, // Allow partially used orders to be filled.
                          revertOnInvalid
                      )
                  ) {
                      // Assuming an invalid order status and no revert, return zero fill.
                      return (orderHash, 0, 0);
                  }
                  // If the order is not already validated, verify the supplied signature.
                  if (!orderStatus.isValidated) {
                      _verifySignature(
                          orderParameters.offerer,
                          orderHash,
                          advancedOrder.signature
                      );
                  }
                  // Read filled amount as numerator and denominator and put on the stack.
                  uint256 filledNumerator = orderStatus.numerator;
                  uint256 filledDenominator = orderStatus.denominator;
                  // If order (orderStatus) currently has a non-zero denominator it is
                  // partially filled.
                  if (filledDenominator != 0) {
                      // If denominator of 1 supplied, fill all remaining amount on order.
                      if (denominator == 1) {
                          // Scale numerator & denominator to match current denominator.
                          numerator = filledDenominator;
                          denominator = filledDenominator;
                      }
                      // Otherwise, if supplied denominator differs from current one...
                      else if (filledDenominator != denominator) {
                          // scale current numerator by the supplied denominator, then...
                          filledNumerator *= denominator;
                          // the supplied numerator & denominator by current denominator.
                          numerator *= filledDenominator;
                          denominator *= filledDenominator;
                      }
                      // Once adjusted, if current+supplied numerator exceeds denominator:
                      if (filledNumerator + numerator > denominator) {
                          // Skip underflow check: denominator >= orderStatus.numerator
                          unchecked {
                              // Reduce current numerator so it + supplied = denominator.
                              numerator = denominator - filledNumerator;
                          }
                      }
                      // Increment the filled numerator by the new numerator.
                      filledNumerator += numerator;
                      // Use assembly to ensure fractional amounts are below max uint120.
                      assembly {
                          // Check filledNumerator and denominator for uint120 overflow.
                          if or(
                              gt(filledNumerator, MaxUint120),
                              gt(denominator, MaxUint120)
                          ) {
                              // Derive greatest common divisor using euclidean algorithm.
                              function gcd(_a, _b) -> out {
                                  for {
                                  } _b {
                                  } {
                                      let _c := _b
                                      _b := mod(_a, _c)
                                      _a := _c
                                  }
                                  out := _a
                              }
                              let scaleDown := gcd(
                                  numerator,
                                  gcd(filledNumerator, denominator)
                              )
                              // Ensure that the divisor is at least one.
                              let safeScaleDown := add(scaleDown, iszero(scaleDown))
                              // Scale all fractional values down by gcd.
                              numerator := div(numerator, safeScaleDown)
                              filledNumerator := div(filledNumerator, safeScaleDown)
                              denominator := div(denominator, safeScaleDown)
                              // Perform the overflow check a second time.
                              if or(
                                  gt(filledNumerator, MaxUint120),
                                  gt(denominator, MaxUint120)
                              ) {
                                  // Store the Panic error signature.
                                  mstore(0, Panic_error_signature)
                                  // Set arithmetic (0x11) panic code as initial argument.
                                  mstore(Panic_error_offset, Panic_arithmetic)
                                  // Return, supplying Panic signature & arithmetic code.
                                  revert(0, Panic_error_length)
                              }
                          }
                      }
                      // Skip overflow check: checked above unless numerator is reduced.
                      unchecked {
                          // Update order status and fill amount, packing struct values.
                          orderStatus.isValidated = true;
                          orderStatus.isCancelled = false;
                          orderStatus.numerator = uint120(filledNumerator);
                          orderStatus.denominator = uint120(denominator);
                      }
                  } else {
                      // Update order status and fill amount, packing struct values.
                      orderStatus.isValidated = true;
                      orderStatus.isCancelled = false;
                      orderStatus.numerator = uint120(numerator);
                      orderStatus.denominator = uint120(denominator);
                  }
                  // Return order hash, a modified numerator, and a modified denominator.
                  return (orderHash, numerator, denominator);
              }
              /**
               * @dev Internal function to cancel an arbitrary number of orders. Note that
               *      only the offerer or the zone of a given order may cancel it. Callers
               *      should ensure that the intended order was cancelled by calling
               *      `getOrderStatus` and confirming that `isCancelled` returns `true`.
               *
               * @param orders The orders to cancel.
               *
               * @return cancelled A boolean indicating whether the supplied orders were
               *                   successfully cancelled.
               */
              function _cancel(OrderComponents[] calldata orders)
                  internal
                  returns (bool cancelled)
              {
                  // Ensure that the reentrancy guard is not currently set.
                  _assertNonReentrant();
                  // Declare variables outside of the loop.
                  OrderStatus storage orderStatus;
                  address offerer;
                  address zone;
                  // Skip overflow check as for loop is indexed starting at zero.
                  unchecked {
                      // Read length of the orders array from memory and place on stack.
                      uint256 totalOrders = orders.length;
                      // Iterate over each order.
                      for (uint256 i = 0; i < totalOrders; ) {
                          // Retrieve the order.
                          OrderComponents calldata order = orders[i];
                          offerer = order.offerer;
                          zone = order.zone;
                          // Ensure caller is either offerer or zone of the order.
                          if (msg.sender != offerer && msg.sender != zone) {
                              revert InvalidCanceller();
                          }
                          // Derive order hash using the order parameters and the counter.
                          bytes32 orderHash = _deriveOrderHash(
                              OrderParameters(
                                  offerer,
                                  zone,
                                  order.offer,
                                  order.consideration,
                                  order.orderType,
                                  order.startTime,
                                  order.endTime,
                                  order.zoneHash,
                                  order.salt,
                                  order.conduitKey,
                                  order.consideration.length
                              ),
                              order.counter
                          );
                          // Retrieve the order status using the derived order hash.
                          orderStatus = _orderStatus[orderHash];
                          // Update the order status as not valid and cancelled.
                          orderStatus.isValidated = false;
                          orderStatus.isCancelled = true;
                          // Emit an event signifying that the order has been cancelled.
                          emit OrderCancelled(orderHash, offerer, zone);
                          // Increment counter inside body of loop for gas efficiency.
                          ++i;
                      }
                  }
                  // Return a boolean indicating that orders were successfully cancelled.
                  cancelled = true;
              }
              /**
               * @dev Internal function to validate an arbitrary number of orders, thereby
               *      registering their signatures as valid and allowing the fulfiller to
               *      skip signature verification on fulfillment. Note that validated
               *      orders may still be unfulfillable due to invalid item amounts or
               *      other factors; callers should determine whether validated orders are
               *      fulfillable by simulating the fulfillment call prior to execution.
               *      Also note that anyone can validate a signed order, but only the
               *      offerer can validate an order without supplying a signature.
               *
               * @param orders The orders to validate.
               *
               * @return validated A boolean indicating whether the supplied orders were
               *                   successfully validated.
               */
              function _validate(Order[] calldata orders)
                  internal
                  returns (bool validated)
              {
                  // Ensure that the reentrancy guard is not currently set.
                  _assertNonReentrant();
                  // Declare variables outside of the loop.
                  OrderStatus storage orderStatus;
                  bytes32 orderHash;
                  address offerer;
                  // Skip overflow check as for loop is indexed starting at zero.
                  unchecked {
                      // Read length of the orders array from memory and place on stack.
                      uint256 totalOrders = orders.length;
                      // Iterate over each order.
                      for (uint256 i = 0; i < totalOrders; ) {
                          // Retrieve the order.
                          Order calldata order = orders[i];
                          // Retrieve the order parameters.
                          OrderParameters calldata orderParameters = order.parameters;
                          // Move offerer from memory to the stack.
                          offerer = orderParameters.offerer;
                          // Get current counter & use it w/ params to derive order hash.
                          orderHash = _assertConsiderationLengthAndGetOrderHash(
                              orderParameters
                          );
                          // Retrieve the order status using the derived order hash.
                          orderStatus = _orderStatus[orderHash];
                          // Ensure order is fillable and retrieve the filled amount.
                          _verifyOrderStatus(
                              orderHash,
                              orderStatus,
                              false, // Signifies that partially filled orders are valid.
                              true // Signifies to revert if the order is invalid.
                          );
                          // If the order has not already been validated...
                          if (!orderStatus.isValidated) {
                              // Verify the supplied signature.
                              _verifySignature(offerer, orderHash, order.signature);
                              // Update order status to mark the order as valid.
                              orderStatus.isValidated = true;
                              // Emit an event signifying the order has been validated.
                              emit OrderValidated(
                                  orderHash,
                                  offerer,
                                  orderParameters.zone
                              );
                          }
                          // Increment counter inside body of the loop for gas efficiency.
                          ++i;
                      }
                  }
                  // Return a boolean indicating that orders were successfully validated.
                  validated = true;
              }
              /**
               * @dev Internal view function to retrieve the status of a given order by
               *      hash, including whether the order has been cancelled or validated
               *      and the fraction of the order that has been filled.
               *
               * @param orderHash The order hash in question.
               *
               * @return isValidated A boolean indicating whether the order in question
               *                     has been validated (i.e. previously approved or
               *                     partially filled).
               * @return isCancelled A boolean indicating whether the order in question
               *                     has been cancelled.
               * @return totalFilled The total portion of the order that has been filled
               *                     (i.e. the "numerator").
               * @return totalSize   The total size of the order that is either filled or
               *                     unfilled (i.e. the "denominator").
               */
              function _getOrderStatus(bytes32 orderHash)
                  internal
                  view
                  returns (
                      bool isValidated,
                      bool isCancelled,
                      uint256 totalFilled,
                      uint256 totalSize
                  )
              {
                  // Retrieve the order status using the order hash.
                  OrderStatus storage orderStatus = _orderStatus[orderHash];
                  // Return the fields on the order status.
                  return (
                      orderStatus.isValidated,
                      orderStatus.isCancelled,
                      orderStatus.numerator,
                      orderStatus.denominator
                  );
              }
              /**
               * @dev Internal pure function to check whether a given order type indicates
               *      that partial fills are not supported (e.g. only "full fills" are
               *      allowed for the order in question).
               *
               * @param orderType The order type in question.
               *
               * @return isFullOrder A boolean indicating whether the order type only
               *                     supports full fills.
               */
              function _doesNotSupportPartialFills(OrderType orderType)
                  internal
                  pure
                  returns (bool isFullOrder)
              {
                  // The "full" order types are even, while "partial" order types are odd.
                  // Bitwise and by 1 is equivalent to modulo by 2, but 2 gas cheaper.
                  assembly {
                      // Equivalent to `uint256(orderType) & 1 == 0`.
                      isFullOrder := iszero(and(orderType, 1))
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { ItemType } from "./ConsiderationEnums.sol";
          // prettier-ignore
          import {
              OfferItem,
              ConsiderationItem,
              SpentItem,
              ReceivedItem,
              OrderParameters,
              Order,
              AdvancedOrder,
              CriteriaResolver
          } from "./ConsiderationStructs.sol";
          import { BasicOrderFulfiller } from "./BasicOrderFulfiller.sol";
          import { CriteriaResolution } from "./CriteriaResolution.sol";
          import { AmountDeriver } from "./AmountDeriver.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title OrderFulfiller
           * @author 0age
           * @notice OrderFulfiller contains logic related to order fulfillment where a
           *         single order is being fulfilled and where basic order fulfillment is
           *         not available as an option.
           */
          contract OrderFulfiller is
              BasicOrderFulfiller,
              CriteriaResolution,
              AmountDeriver
          {
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController)
                  BasicOrderFulfiller(conduitController)
              {}
              /**
               * @dev Internal function to validate an order and update its status, adjust
               *      prices based on current time, apply criteria resolvers, determine
               *      what portion to fill, and transfer relevant tokens.
               *
               * @param advancedOrder       The order to fulfill as well as the fraction
               *                            to fill. Note that all offer and consideration
               *                            components must divide with no remainder for
               *                            the partial fill to be valid.
               * @param criteriaResolvers   An array where each element contains a
               *                            reference to a specific offer or
               *                            consideration, a token identifier, and a proof
               *                            that the supplied token identifier is
               *                            contained in the order's merkle root. Note
               *                            that a criteria of zero indicates that any
               *                            (transferable) token identifier is valid and
               *                            that no proof needs to be supplied.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used, with direct approvals set on
               *                            Consideration.
               * @param recipient           The intended recipient for all received items.
               *
               * @return A boolean indicating whether the order has been fulfilled.
               */
              function _validateAndFulfillAdvancedOrder(
                  AdvancedOrder memory advancedOrder,
                  CriteriaResolver[] memory criteriaResolvers,
                  bytes32 fulfillerConduitKey,
                  address recipient
              ) internal returns (bool) {
                  // Ensure this function cannot be triggered during a reentrant call.
                  _setReentrancyGuard();
                  // Declare empty bytes32 array (unused, will remain empty).
                  bytes32[] memory priorOrderHashes;
                  // Validate order, update status, and determine fraction to fill.
                  (
                      bytes32 orderHash,
                      uint256 fillNumerator,
                      uint256 fillDenominator
                  ) = _validateOrderAndUpdateStatus(
                          advancedOrder,
                          criteriaResolvers,
                          true,
                          priorOrderHashes
                      );
                  // Create an array with length 1 containing the order.
                  AdvancedOrder[] memory advancedOrders = new AdvancedOrder[](1);
                  // Populate the order as the first and only element of the new array.
                  advancedOrders[0] = advancedOrder;
                  // Apply criteria resolvers using generated orders and details arrays.
                  _applyCriteriaResolvers(advancedOrders, criteriaResolvers);
                  // Retrieve the order parameters after applying criteria resolvers.
                  OrderParameters memory orderParameters = advancedOrders[0].parameters;
                  // Perform each item transfer with the appropriate fractional amount.
                  _applyFractionsAndTransferEach(
                      orderParameters,
                      fillNumerator,
                      fillDenominator,
                      fulfillerConduitKey,
                      recipient
                  );
                  // Emit an event signifying that the order has been fulfilled.
                  _emitOrderFulfilledEvent(
                      orderHash,
                      orderParameters.offerer,
                      orderParameters.zone,
                      recipient,
                      orderParameters.offer,
                      orderParameters.consideration
                  );
                  // Clear the reentrancy guard.
                  _clearReentrancyGuard();
                  return true;
              }
              /**
               * @dev Internal function to transfer each item contained in a given single
               *      order fulfillment after applying a respective fraction to the amount
               *      being transferred.
               *
               * @param orderParameters     The parameters for the fulfilled order.
               * @param numerator           A value indicating the portion of the order
               *                            that should be filled.
               * @param denominator         A value indicating the total order size.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used, with direct approvals set on
               *                            Consideration.
               * @param recipient           The intended recipient for all received items.
               */
              function _applyFractionsAndTransferEach(
                  OrderParameters memory orderParameters,
                  uint256 numerator,
                  uint256 denominator,
                  bytes32 fulfillerConduitKey,
                  address recipient
              ) internal {
                  // Read start time & end time from order parameters and place on stack.
                  uint256 startTime = orderParameters.startTime;
                  uint256 endTime = orderParameters.endTime;
                  // Initialize an accumulator array. From this point forward, no new
                  // memory regions can be safely allocated until the accumulator is no
                  // longer being utilized, as the accumulator operates in an open-ended
                  // fashion from this memory pointer; existing memory may still be
                  // accessed and modified, however.
                  bytes memory accumulator = new bytes(AccumulatorDisarmed);
                  // As of solidity 0.6.0, inline assembly cannot directly access function
                  // definitions, but can still access locally scoped function variables.
                  // This means that in order to recast the type of a function, we need to
                  // create a local variable to reference the internal function definition
                  // (using the same type) and a local variable with the desired type,
                  // and then cast the original function pointer to the desired type.
                  /**
                   * Repurpose existing OfferItem memory regions on the offer array for
                   * the order by overriding the _transfer function pointer to accept a
                   * modified OfferItem argument in place of the usual ReceivedItem:
                   *
                   *   ========= OfferItem ==========   ====== ReceivedItem ======
                   *   ItemType itemType; ------------> ItemType itemType;
                   *   address token; ----------------> address token;
                   *   uint256 identifierOrCriteria; -> uint256 identifier;
                   *   uint256 startAmount; ----------> uint256 amount;
                   *   uint256 endAmount; ------------> address recipient;
                   */
                  // Declare a nested scope to minimize stack depth.
                  unchecked {
                      // Declare a virtual function pointer taking an OfferItem argument.
                      function(OfferItem memory, address, bytes32, bytes memory)
                          internal _transferOfferItem;
                      {
                          // Assign _transfer function to a new function pointer (it takes
                          // a ReceivedItem as its initial argument)
                          function(ReceivedItem memory, address, bytes32, bytes memory)
                              internal _transferReceivedItem = _transfer;
                          // Utilize assembly to override the virtual function pointer.
                          assembly {
                              // Cast initial ReceivedItem type to an OfferItem type.
                              _transferOfferItem := _transferReceivedItem
                          }
                      }
                      // Read offer array length from memory and place on stack.
                      uint256 totalOfferItems = orderParameters.offer.length;
                      // Iterate over each offer on the order.
                      // Skip overflow check as for loop is indexed starting at zero.
                      for (uint256 i = 0; i < totalOfferItems; ++i) {
                          // Retrieve the offer item.
                          OfferItem memory offerItem = orderParameters.offer[i];
                          // Offer items for the native token can not be received
                          // outside of a match order function.
                          if (offerItem.itemType == ItemType.NATIVE) {
                              revert InvalidNativeOfferItem();
                          }
                          // Declare an additional nested scope to minimize stack depth.
                          {
                              // Apply fill fraction to get offer item amount to transfer.
                              uint256 amount = _applyFraction(
                                  offerItem.startAmount,
                                  offerItem.endAmount,
                                  numerator,
                                  denominator,
                                  startTime,
                                  endTime,
                                  false
                              );
                              // Utilize assembly to set overloaded offerItem arguments.
                              assembly {
                                  // Write new fractional amount to startAmount as amount.
                                  mstore(
                                      add(offerItem, ReceivedItem_amount_offset),
                                      amount
                                  )
                                  // Write recipient to endAmount.
                                  mstore(
                                      add(offerItem, ReceivedItem_recipient_offset),
                                      recipient
                                  )
                              }
                          }
                          // Transfer the item from the offerer to the recipient.
                          _transferOfferItem(
                              offerItem,
                              orderParameters.offerer,
                              orderParameters.conduitKey,
                              accumulator
                          );
                      }
                  }
                  // Put ether value supplied by the caller on the stack.
                  uint256 etherRemaining = msg.value;
                  /**
                   * Repurpose existing ConsiderationItem memory regions on the
                   * consideration array for the order by overriding the _transfer
                   * function pointer to accept a modified ConsiderationItem argument in
                   * place of the usual ReceivedItem:
                   *
                   *   ====== ConsiderationItem =====   ====== ReceivedItem ======
                   *   ItemType itemType; ------------> ItemType itemType;
                   *   address token; ----------------> address token;
                   *   uint256 identifierOrCriteria;--> uint256 identifier;
                   *   uint256 startAmount; ----------> uint256 amount;
                   *   uint256 endAmount;        /----> address recipient;
                   *   address recipient; ------/
                   */
                  // Declare a nested scope to minimize stack depth.
                  unchecked {
                      // Declare virtual function pointer with ConsiderationItem argument.
                      function(ConsiderationItem memory, address, bytes32, bytes memory)
                          internal _transferConsiderationItem;
                      {
                          // Reassign _transfer function to a new function pointer (it
                          // takes a ReceivedItem as its initial argument).
                          function(ReceivedItem memory, address, bytes32, bytes memory)
                              internal _transferReceivedItem = _transfer;
                          // Utilize assembly to override the virtual function pointer.
                          assembly {
                              // Cast ReceivedItem type to ConsiderationItem type.
                              _transferConsiderationItem := _transferReceivedItem
                          }
                      }
                      // Read consideration array length from memory and place on stack.
                      uint256 totalConsiderationItems = orderParameters
                          .consideration
                          .length;
                      // Iterate over each consideration item on the order.
                      // Skip overflow check as for loop is indexed starting at zero.
                      for (uint256 i = 0; i < totalConsiderationItems; ++i) {
                          // Retrieve the consideration item.
                          ConsiderationItem memory considerationItem = (
                              orderParameters.consideration[i]
                          );
                          // Apply fraction & derive considerationItem amount to transfer.
                          uint256 amount = _applyFraction(
                              considerationItem.startAmount,
                              considerationItem.endAmount,
                              numerator,
                              denominator,
                              startTime,
                              endTime,
                              true
                          );
                          // Use assembly to set overloaded considerationItem arguments.
                          assembly {
                              // Write derived fractional amount to startAmount as amount.
                              mstore(
                                  add(considerationItem, ReceivedItem_amount_offset),
                                  amount
                              )
                              // Write original recipient to endAmount as recipient.
                              mstore(
                                  add(considerationItem, ReceivedItem_recipient_offset),
                                  mload(
                                      add(
                                          considerationItem,
                                          ConsiderationItem_recipient_offset
                                      )
                                  )
                              )
                          }
                          // Reduce available value if offer spent ETH or a native token.
                          if (considerationItem.itemType == ItemType.NATIVE) {
                              // Ensure that sufficient native tokens are still available.
                              if (amount > etherRemaining) {
                                  revert InsufficientEtherSupplied();
                              }
                              // Skip underflow check as a comparison has just been made.
                              etherRemaining -= amount;
                          }
                          // Transfer item from caller to recipient specified by the item.
                          _transferConsiderationItem(
                              considerationItem,
                              msg.sender,
                              fulfillerConduitKey,
                              accumulator
                          );
                      }
                  }
                  // Trigger any remaining accumulated transfers via call to the conduit.
                  _triggerIfArmed(accumulator);
                  // If any ether remains after fulfillments...
                  if (etherRemaining != 0) {
                      // return it to the caller.
                      _transferEth(payable(msg.sender), etherRemaining);
                  }
              }
              /**
               * @dev Internal function to emit an OrderFulfilled event. OfferItems are
               *      translated into SpentItems and ConsiderationItems are translated
               *      into ReceivedItems.
               *
               * @param orderHash     The order hash.
               * @param offerer       The offerer for the order.
               * @param zone          The zone for the order.
               * @param fulfiller     The fulfiller of the order, or the null address if
               *                      the order was fulfilled via order matching.
               * @param offer         The offer items for the order.
               * @param consideration The consideration items for the order.
               */
              function _emitOrderFulfilledEvent(
                  bytes32 orderHash,
                  address offerer,
                  address zone,
                  address fulfiller,
                  OfferItem[] memory offer,
                  ConsiderationItem[] memory consideration
              ) internal {
                  // Cast already-modified offer memory region as spent items.
                  SpentItem[] memory spentItems;
                  assembly {
                      spentItems := offer
                  }
                  // Cast already-modified consideration memory region as received items.
                  ReceivedItem[] memory receivedItems;
                  assembly {
                      receivedItems := consideration
                  }
                  // Emit an event signifying that the order has been fulfilled.
                  emit OrderFulfilled(
                      orderHash,
                      offerer,
                      zone,
                      fulfiller,
                      spentItems,
                      receivedItems
                  );
              }
              /**
               * @dev Internal pure function to convert an order to an advanced order with
               *      numerator and denominator of 1 and empty extraData.
               *
               * @param order The order to convert.
               *
               * @return advancedOrder The new advanced order.
               */
              function _convertOrderToAdvanced(Order calldata order)
                  internal
                  pure
                  returns (AdvancedOrder memory advancedOrder)
              {
                  // Convert to partial order (1/1 or full fill) and return new value.
                  advancedOrder = AdvancedOrder(
                      order.parameters,
                      1,
                      1,
                      order.signature,
                      ""
                  );
              }
              /**
               * @dev Internal pure function to convert an array of orders to an array of
               *      advanced orders with numerator and denominator of 1.
               *
               * @param orders The orders to convert.
               *
               * @return advancedOrders The new array of partial orders.
               */
              function _convertOrdersToAdvanced(Order[] calldata orders)
                  internal
                  pure
                  returns (AdvancedOrder[] memory advancedOrders)
              {
                  // Read the number of orders from calldata and place on the stack.
                  uint256 totalOrders = orders.length;
                  // Allocate new empty array for each partial order in memory.
                  advancedOrders = new AdvancedOrder[](totalOrders);
                  // Skip overflow check as the index for the loop starts at zero.
                  unchecked {
                      // Iterate over the given orders.
                      for (uint256 i = 0; i < totalOrders; ++i) {
                          // Convert to partial order (1/1 or full fill) and update array.
                          advancedOrders[i] = _convertOrderToAdvanced(orders[i]);
                      }
                  }
                  // Return the array of advanced orders.
                  return advancedOrders;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          // prettier-ignore
          import {
              AmountDerivationErrors
          } from "../interfaces/AmountDerivationErrors.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title AmountDeriver
           * @author 0age
           * @notice AmountDeriver contains view and pure functions related to deriving
           *         item amounts based on partial fill quantity and on linear
           *         interpolation based on current time when the start amount and end
           *         amount differ.
           */
          contract AmountDeriver is AmountDerivationErrors {
              /**
               * @dev Internal view function to derive the current amount of a given item
               *      based on the current price, the starting price, and the ending
               *      price. If the start and end prices differ, the current price will be
               *      interpolated on a linear basis. Note that this function expects that
               *      the startTime parameter of orderParameters is not greater than the
               *      current block timestamp and that the endTime parameter is greater
               *      than the current block timestamp. If this condition is not upheld,
               *      duration / elapsed / remaining variables will underflow.
               *
               * @param startAmount The starting amount of the item.
               * @param endAmount   The ending amount of the item.
               * @param startTime   The starting time of the order.
               * @param endTime     The end time of the order.
               * @param roundUp     A boolean indicating whether the resultant amount
               *                    should be rounded up or down.
               *
               * @return amount The current amount.
               */
              function _locateCurrentAmount(
                  uint256 startAmount,
                  uint256 endAmount,
                  uint256 startTime,
                  uint256 endTime,
                  bool roundUp
              ) internal view returns (uint256 amount) {
                  // Only modify end amount if it doesn't already equal start amount.
                  if (startAmount != endAmount) {
                      // Declare variables to derive in the subsequent unchecked scope.
                      uint256 duration;
                      uint256 elapsed;
                      uint256 remaining;
                      // Skip underflow checks as startTime <= block.timestamp < endTime.
                      unchecked {
                          // Derive the duration for the order and place it on the stack.
                          duration = endTime - startTime;
                          // Derive time elapsed since the order started & place on stack.
                          elapsed = block.timestamp - startTime;
                          // Derive time remaining until order expires and place on stack.
                          remaining = duration - elapsed;
                      }
                      // Aggregate new amounts weighted by time with rounding factor.
                      uint256 totalBeforeDivision = ((startAmount * remaining) +
                          (endAmount * elapsed));
                      // Use assembly to combine operations and skip divide-by-zero check.
                      assembly {
                          // Multiply by iszero(iszero(totalBeforeDivision)) to ensure
                          // amount is set to zero if totalBeforeDivision is zero,
                          // as intermediate overflow can occur if it is zero.
                          amount := mul(
                              iszero(iszero(totalBeforeDivision)),
                              // Subtract 1 from the numerator and add 1 to the result if
                              // roundUp is true to get the proper rounding direction.
                              // Division is performed with no zero check as duration
                              // cannot be zero as long as startTime < endTime.
                              add(
                                  div(sub(totalBeforeDivision, roundUp), duration),
                                  roundUp
                              )
                          )
                      }
                      // Return the current amount.
                      return amount;
                  }
                  // Return the original amount as startAmount == endAmount.
                  return endAmount;
              }
              /**
               * @dev Internal pure function to return a fraction of a given value and to
               *      ensure the resultant value does not have any fractional component.
               *      Note that this function assumes that zero will never be supplied as
               *      the denominator parameter; invalid / undefined behavior will result
               *      should a denominator of zero be provided.
               *
               * @param numerator   A value indicating the portion of the order that
               *                    should be filled.
               * @param denominator A value indicating the total size of the order. Note
               *                    that this value cannot be equal to zero.
               * @param value       The value for which to compute the fraction.
               *
               * @return newValue The value after applying the fraction.
               */
              function _getFraction(
                  uint256 numerator,
                  uint256 denominator,
                  uint256 value
              ) internal pure returns (uint256 newValue) {
                  // Return value early in cases where the fraction resolves to 1.
                  if (numerator == denominator) {
                      return value;
                  }
                  // Ensure fraction can be applied to the value with no remainder. Note
                  // that the denominator cannot be zero.
                  assembly {
                      // Ensure new value contains no remainder via mulmod operator.
                      // Credit to @hrkrshnn + @axic for proposing this optimal solution.
                      if mulmod(value, numerator, denominator) {
                          mstore(0, InexactFraction_error_signature)
                          revert(0, InexactFraction_error_len)
                      }
                  }
                  // Multiply the numerator by the value and ensure no overflow occurs.
                  uint256 valueTimesNumerator = value * numerator;
                  // Divide and check for remainder. Note that denominator cannot be zero.
                  assembly {
                      // Perform division without zero check.
                      newValue := div(valueTimesNumerator, denominator)
                  }
              }
              /**
               * @dev Internal view function to apply a fraction to a consideration
               * or offer item.
               *
               * @param startAmount     The starting amount of the item.
               * @param endAmount       The ending amount of the item.
               * @param numerator       A value indicating the portion of the order that
               *                        should be filled.
               * @param denominator     A value indicating the total size of the order.
               * @param startTime       The starting time of the order.
               * @param endTime         The end time of the order.
               * @param roundUp         A boolean indicating whether the resultant
               *                        amount should be rounded up or down.
               *
               * @return amount The received item to transfer with the final amount.
               */
              function _applyFraction(
                  uint256 startAmount,
                  uint256 endAmount,
                  uint256 numerator,
                  uint256 denominator,
                  uint256 startTime,
                  uint256 endTime,
                  bool roundUp
              ) internal view returns (uint256 amount) {
                  // If start amount equals end amount, apply fraction to end amount.
                  if (startAmount == endAmount) {
                      // Apply fraction to end amount.
                      amount = _getFraction(numerator, denominator, endAmount);
                  } else {
                      // Otherwise, apply fraction to both and interpolated final amount.
                      amount = _locateCurrentAmount(
                          _getFraction(numerator, denominator, startAmount),
                          _getFraction(numerator, denominator, endAmount),
                          startTime,
                          endTime,
                          roundUp
                      );
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title AmountDerivationErrors
           * @author 0age
           * @notice AmountDerivationErrors contains errors related to amount derivation.
           */
          interface AmountDerivationErrors {
              /**
               * @dev Revert with an error when attempting to apply a fraction as part of
               *      a partial fill that does not divide the target amount cleanly.
               */
              error InexactFraction();
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          import { Side, ItemType } from "./ConsiderationEnums.sol";
          // prettier-ignore
          import {
              OfferItem,
              ConsiderationItem,
              ReceivedItem,
              OrderParameters,
              Fulfillment,
              FulfillmentComponent,
              Execution,
              Order,
              AdvancedOrder,
              CriteriaResolver
          } from "./ConsiderationStructs.sol";
          import { OrderFulfiller } from "./OrderFulfiller.sol";
          import { FulfillmentApplier } from "./FulfillmentApplier.sol";
          import "./ConsiderationConstants.sol";
          /**
           * @title OrderCombiner
           * @author 0age
           * @notice OrderCombiner contains logic for fulfilling combinations of orders,
           *         either by matching offer items to consideration items or by
           *         fulfilling orders where available.
           */
          contract OrderCombiner is OrderFulfiller, FulfillmentApplier {
              /**
               * @dev Derive and set hashes, reference chainId, and associated domain
               *      separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) OrderFulfiller(conduitController) {}
              /**
               * @notice Internal function to attempt to fill a group of orders, fully or
               *         partially, with an arbitrary number of items for offer and
               *         consideration per order alongside criteria resolvers containing
               *         specific token identifiers and associated proofs. Any order that
               *         is not currently active, has already been fully filled, or has
               *         been cancelled will be omitted. Remaining offer and consideration
               *         items will then be aggregated where possible as indicated by the
               *         supplied offer and consideration component arrays and aggregated
               *         items will be transferred to the fulfiller or to each intended
               *         recipient, respectively. Note that a failing item transfer or an
               *         issue with order formatting will cause the entire batch to fail.
               *
               * @param advancedOrders            The orders to fulfill along with the
               *                                  fraction of those orders to attempt to
               *                                  fill. Note that both the offerer and the
               *                                  fulfiller must first approve this
               *                                  contract (or a conduit if indicated by
               *                                  the order) to transfer any relevant
               *                                  tokens on their behalf and that
               *                                  contracts must implement
               *                                  `onERC1155Received` in order to receive
               *                                  ERC1155 tokens as consideration. Also
               *                                  note that all offer and consideration
               *                                  components must have no remainder after
               *                                  multiplication of the respective amount
               *                                  with the supplied fraction for an
               *                                  order's partial fill amount to be
               *                                  considered valid.
               * @param criteriaResolvers         An array where each element contains a
               *                                  reference to a specific offer or
               *                                  consideration, a token identifier, and a
               *                                  proof that the supplied token identifier
               *                                  is contained in the merkle root held by
               *                                  the item in question's criteria element.
               *                                  Note that an empty criteria indicates
               *                                  that any (transferable) token
               *                                  identifier on the token in question is
               *                                  valid and that no associated proof needs
               *                                  to be supplied.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used (and
               *                                  direct approvals set on Consideration).
               * @param recipient                 The intended recipient for all received
               *                                  items.
               * @param maximumFulfilled          The maximum number of orders to fulfill.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function _fulfillAvailableAdvancedOrders(
                  AdvancedOrder[] memory advancedOrders,
                  CriteriaResolver[] memory criteriaResolvers,
                  FulfillmentComponent[][] calldata offerFulfillments,
                  FulfillmentComponent[][] calldata considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  address recipient,
                  uint256 maximumFulfilled
              )
                  internal
                  returns (bool[] memory availableOrders, Execution[] memory executions)
              {
                  // Validate orders, apply amounts, & determine if they utilize conduits.
                  _validateOrdersAndPrepareToFulfill(
                      advancedOrders,
                      criteriaResolvers,
                      false, // Signifies that invalid orders should NOT revert.
                      maximumFulfilled,
                      recipient
                  );
                  // Aggregate used offer and consideration items and execute transfers.
                  (availableOrders, executions) = _executeAvailableFulfillments(
                      advancedOrders,
                      offerFulfillments,
                      considerationFulfillments,
                      fulfillerConduitKey,
                      recipient
                  );
                  // Return order fulfillment details and executions.
                  return (availableOrders, executions);
              }
              /**
               * @dev Internal function to validate a group of orders, update their
               *      statuses, reduce amounts by their previously filled fractions, apply
               *      criteria resolvers, and emit OrderFulfilled events.
               *
               * @param advancedOrders    The advanced orders to validate and reduce by
               *                          their previously filled amounts.
               * @param criteriaResolvers An array where each element contains a reference
               *                          to a specific order as well as that order's
               *                          offer or consideration, a token identifier, and
               *                          a proof that the supplied token identifier is
               *                          contained in the order's merkle root. Note that
               *                          a root of zero indicates that any transferable
               *                          token identifier is valid and that no proof
               *                          needs to be supplied.
               * @param revertOnInvalid   A boolean indicating whether to revert on any
               *                          order being invalid; setting this to false will
               *                          instead cause the invalid order to be skipped.
               * @param maximumFulfilled  The maximum number of orders to fulfill.
               * @param recipient         The intended recipient for all received items.
               */
              function _validateOrdersAndPrepareToFulfill(
                  AdvancedOrder[] memory advancedOrders,
                  CriteriaResolver[] memory criteriaResolvers,
                  bool revertOnInvalid,
                  uint256 maximumFulfilled,
                  address recipient
              ) internal {
                  // Ensure this function cannot be triggered during a reentrant call.
                  _setReentrancyGuard();
                  // Read length of orders array and place on the stack.
                  uint256 totalOrders = advancedOrders.length;
                  // Track the order hash for each order being fulfilled.
                  bytes32[] memory orderHashes = new bytes32[](totalOrders);
                  // Override orderHashes length to zero after memory has been allocated.
                  assembly {
                      mstore(orderHashes, 0)
                  }
                  // Declare an error buffer indicating status of any native offer items.
                  // {00} == 0 => In a match function, no native offer items: allow.
                  // {01} == 1 => In a match function, some native offer items: allow.
                  // {10} == 2 => Not in a match function, no native offer items: allow.
                  // {11} == 3 => Not in a match function, some native offer items: THROW.
                  uint256 invalidNativeOfferItemErrorBuffer;
                  // Use assembly to set the value for the second bit of the error buffer.
                  assembly {
                      // Use the second bit of the error buffer to indicate whether the
                      // current function is not matchAdvancedOrders or matchOrders.
                      invalidNativeOfferItemErrorBuffer := shl(
                          1,
                          gt(
                              // Take the remainder of the selector modulo a magic value.
                              mod(
                                  shr(NumBitsAfterSelector, calldataload(0)),
                                  NonMatchSelector_MagicModulus
                              ),
                              // Check if remainder is higher than the greatest remainder
                              // of the two match selectors modulo the magic value.
                              NonMatchSelector_MagicRemainder
                          )
                      )
                  }
                  // Skip overflow checks as all for loops are indexed starting at zero.
                  unchecked {
                      // Iterate over each order.
                      for (uint256 i = 0; i < totalOrders; ++i) {
                          // Retrieve the current order.
                          AdvancedOrder memory advancedOrder = advancedOrders[i];
                          // Determine if max number orders have already been fulfilled.
                          if (maximumFulfilled == 0) {
                              // Mark fill fraction as zero as the order will not be used.
                              advancedOrder.numerator = 0;
                              // Update the length of the orderHashes array.
                              assembly {
                                  mstore(orderHashes, add(i, 1))
                              }
                              // Continue iterating through the remaining orders.
                              continue;
                          }
                          // Validate it, update status, and determine fraction to fill.
                          (
                              bytes32 orderHash,
                              uint256 numerator,
                              uint256 denominator
                          ) = _validateOrderAndUpdateStatus(
                                  advancedOrder,
                                  criteriaResolvers,
                                  revertOnInvalid,
                                  orderHashes
                              );
                          // Update the length of the orderHashes array.
                          assembly {
                              mstore(orderHashes, add(i, 1))
                          }
                          // Do not track hash or adjust prices if order is not fulfilled.
                          if (numerator == 0) {
                              // Mark fill fraction as zero if the order is not fulfilled.
                              advancedOrder.numerator = 0;
                              // Continue iterating through the remaining orders.
                              continue;
                          }
                          // Otherwise, track the order hash in question.
                          orderHashes[i] = orderHash;
                          // Decrement the number of fulfilled orders.
                          // Skip underflow check as the condition before
                          // implies that maximumFulfilled > 0.
                          maximumFulfilled--;
                          // Place the start time for the order on the stack.
                          uint256 startTime = advancedOrder.parameters.startTime;
                          // Place the end time for the order on the stack.
                          uint256 endTime = advancedOrder.parameters.endTime;
                          // Retrieve array of offer items for the order in question.
                          OfferItem[] memory offer = advancedOrder.parameters.offer;
                          // Read length of offer array and place on the stack.
                          uint256 totalOfferItems = offer.length;
                          // Iterate over each offer item on the order.
                          for (uint256 j = 0; j < totalOfferItems; ++j) {
                              // Retrieve the offer item.
                              OfferItem memory offerItem = offer[j];
                              assembly {
                                  // If the offer item is for the native token, set the
                                  // first bit of the error buffer to true.
                                  invalidNativeOfferItemErrorBuffer := or(
                                      invalidNativeOfferItemErrorBuffer,
                                      iszero(mload(offerItem))
                                  )
                              }
                              // Apply order fill fraction to offer item end amount.
                              uint256 endAmount = _getFraction(
                                  numerator,
                                  denominator,
                                  offerItem.endAmount
                              );
                              // Reuse same fraction if start and end amounts are equal.
                              if (offerItem.startAmount == offerItem.endAmount) {
                                  // Apply derived amount to both start and end amount.
                                  offerItem.startAmount = endAmount;
                              } else {
                                  // Apply order fill fraction to offer item start amount.
                                  offerItem.startAmount = _getFraction(
                                      numerator,
                                      denominator,
                                      offerItem.startAmount
                                  );
                              }
                              // Update end amount in memory to match the derived amount.
                              offerItem.endAmount = endAmount;
                              // Adjust offer amount using current time; round down.
                              offerItem.startAmount = _locateCurrentAmount(
                                  offerItem.startAmount,
                                  offerItem.endAmount,
                                  startTime,
                                  endTime,
                                  false // round down
                              );
                          }
                          // Retrieve array of consideration items for order in question.
                          ConsiderationItem[] memory consideration = (
                              advancedOrder.parameters.consideration
                          );
                          // Read length of consideration array and place on the stack.
                          uint256 totalConsiderationItems = consideration.length;
                          // Iterate over each consideration item on the order.
                          for (uint256 j = 0; j < totalConsiderationItems; ++j) {
                              // Retrieve the consideration item.
                              ConsiderationItem memory considerationItem = (
                                  consideration[j]
                              );
                              // Apply fraction to consideration item end amount.
                              uint256 endAmount = _getFraction(
                                  numerator,
                                  denominator,
                                  considerationItem.endAmount
                              );
                              // Reuse same fraction if start and end amounts are equal.
                              if (
                                  considerationItem.startAmount ==
                                  considerationItem.endAmount
                              ) {
                                  // Apply derived amount to both start and end amount.
                                  considerationItem.startAmount = endAmount;
                              } else {
                                  // Apply fraction to consideration item start amount.
                                  considerationItem.startAmount = _getFraction(
                                      numerator,
                                      denominator,
                                      considerationItem.startAmount
                                  );
                              }
                              // Update end amount in memory to match the derived amount.
                              considerationItem.endAmount = endAmount;
                              // Adjust consideration amount using current time; round up.
                              considerationItem.startAmount = (
                                  _locateCurrentAmount(
                                      considerationItem.startAmount,
                                      considerationItem.endAmount,
                                      startTime,
                                      endTime,
                                      true // round up
                                  )
                              );
                              // Utilize assembly to manually "shift" the recipient value.
                              assembly {
                                  // Write recipient to endAmount, as endAmount is not
                                  // used from this point on and can be repurposed to fit
                                  // the layout of a ReceivedItem.
                                  mstore(
                                      add(
                                          considerationItem,
                                          ReceivedItem_recipient_offset // old endAmount
                                      ),
                                      mload(
                                          add(
                                              considerationItem,
                                              ConsiderationItem_recipient_offset
                                          )
                                      )
                                  )
                              }
                          }
                      }
                  }
                  // If the first bit is set, a native offer item was encountered. If the
                  // second bit is set in the error buffer, the current function is not
                  // matchOrders or matchAdvancedOrders. If the value is three, both the
                  // first and second bits were set; in that case, revert with an error.
                  if (invalidNativeOfferItemErrorBuffer == 3) {
                      revert InvalidNativeOfferItem();
                  }
                  // Apply criteria resolvers to each order as applicable.
                  _applyCriteriaResolvers(advancedOrders, criteriaResolvers);
                  // Emit an event for each order signifying that it has been fulfilled.
                  // Skip overflow checks as all for loops are indexed starting at zero.
                  unchecked {
                      // Iterate over each order.
                      for (uint256 i = 0; i < totalOrders; ++i) {
                          // Do not emit an event if no order hash is present.
                          if (orderHashes[i] == bytes32(0)) {
                              continue;
                          }
                          // Retrieve parameters for the order in question.
                          OrderParameters memory orderParameters = (
                              advancedOrders[i].parameters
                          );
                          // Emit an OrderFulfilled event.
                          _emitOrderFulfilledEvent(
                              orderHashes[i],
                              orderParameters.offerer,
                              orderParameters.zone,
                              recipient,
                              orderParameters.offer,
                              orderParameters.consideration
                          );
                      }
                  }
              }
              /**
               * @dev Internal function to fulfill a group of validated orders, fully or
               *      partially, with an arbitrary number of items for offer and
               *      consideration per order and to execute transfers. Any order that is
               *      not currently active, has already been fully filled, or has been
               *      cancelled will be omitted. Remaining offer and consideration items
               *      will then be aggregated where possible as indicated by the supplied
               *      offer and consideration component arrays and aggregated items will
               *      be transferred to the fulfiller or to each intended recipient,
               *      respectively. Note that a failing item transfer or an issue with
               *      order formatting will cause the entire batch to fail.
               *
               * @param advancedOrders            The orders to fulfill along with the
               *                                  fraction of those orders to attempt to
               *                                  fill. Note that both the offerer and the
               *                                  fulfiller must first approve this
               *                                  contract (or the conduit if indicated by
               *                                  the order) to transfer any relevant
               *                                  tokens on their behalf and that
               *                                  contracts must implement
               *                                  `onERC1155Received` in order to receive
               *                                  ERC1155 tokens as consideration. Also
               *                                  note that all offer and consideration
               *                                  components must have no remainder after
               *                                  multiplication of the respective amount
               *                                  with the supplied fraction for an
               *                                  order's partial fill amount to be
               *                                  considered valid.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used, with
               *                                  direct approvals set on Consideration.
               * @param recipient                 The intended recipient for all received
               *                                  items.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function _executeAvailableFulfillments(
                  AdvancedOrder[] memory advancedOrders,
                  FulfillmentComponent[][] memory offerFulfillments,
                  FulfillmentComponent[][] memory considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  address recipient
              )
                  internal
                  returns (bool[] memory availableOrders, Execution[] memory executions)
              {
                  // Retrieve length of offer fulfillments array and place on the stack.
                  uint256 totalOfferFulfillments = offerFulfillments.length;
                  // Retrieve length of consideration fulfillments array & place on stack.
                  uint256 totalConsiderationFulfillments = (
                      considerationFulfillments.length
                  );
                  // Allocate an execution for each offer and consideration fulfillment.
                  executions = new Execution[](
                      totalOfferFulfillments + totalConsiderationFulfillments
                  );
                  // Skip overflow checks as all for loops are indexed starting at zero.
                  unchecked {
                      // Track number of filtered executions.
                      uint256 totalFilteredExecutions = 0;
                      // Iterate over each offer fulfillment.
                      for (uint256 i = 0; i < totalOfferFulfillments; ++i) {
                          /// Retrieve the offer fulfillment components in question.
                          FulfillmentComponent[] memory components = (
                              offerFulfillments[i]
                          );
                          // Derive aggregated execution corresponding with fulfillment.
                          Execution memory execution = _aggregateAvailable(
                              advancedOrders,
                              Side.OFFER,
                              components,
                              fulfillerConduitKey,
                              recipient
                          );
                          // If offerer and recipient on the execution are the same...
                          if (execution.item.recipient == execution.offerer) {
                              // Increment total filtered executions.
                              ++totalFilteredExecutions;
                          } else {
                              // Otherwise, assign the execution to the executions array.
                              executions[i - totalFilteredExecutions] = execution;
                          }
                      }
                      // Iterate over each consideration fulfillment.
                      for (uint256 i = 0; i < totalConsiderationFulfillments; ++i) {
                          /// Retrieve consideration fulfillment components in question.
                          FulfillmentComponent[] memory components = (
                              considerationFulfillments[i]
                          );
                          // Derive aggregated execution corresponding with fulfillment.
                          Execution memory execution = _aggregateAvailable(
                              advancedOrders,
                              Side.CONSIDERATION,
                              components,
                              fulfillerConduitKey,
                              address(0) // unused
                          );
                          // If offerer and recipient on the execution are the same...
                          if (execution.item.recipient == execution.offerer) {
                              // Increment total filtered executions.
                              ++totalFilteredExecutions;
                          } else {
                              // Otherwise, assign the execution to the executions array.
                              executions[
                                  i + totalOfferFulfillments - totalFilteredExecutions
                              ] = execution;
                          }
                      }
                      // If some number of executions have been filtered...
                      if (totalFilteredExecutions != 0) {
                          // reduce the total length of the executions array.
                          assembly {
                              mstore(
                                  executions,
                                  sub(mload(executions), totalFilteredExecutions)
                              )
                          }
                      }
                  }
                  // Revert if no orders are available.
                  if (executions.length == 0) {
                      revert NoSpecifiedOrdersAvailable();
                  }
                  // Perform final checks and return.
                  availableOrders = _performFinalChecksAndExecuteOrders(
                      advancedOrders,
                      executions
                  );
                  return (availableOrders, executions);
              }
              /**
               * @dev Internal function to perform a final check that each consideration
               *      item for an arbitrary number of fulfilled orders has been met and to
               *      trigger associated executions, transferring the respective items.
               *
               * @param advancedOrders     The orders to check and perform executions for.
               * @param executions         An array of elements indicating the sequence of
               *                           transfers to perform when fulfilling the given
               *                           orders.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               */
              function _performFinalChecksAndExecuteOrders(
                  AdvancedOrder[] memory advancedOrders,
                  Execution[] memory executions
              ) internal returns (bool[] memory availableOrders) {
                  // Retrieve the length of the advanced orders array and place on stack.
                  uint256 totalOrders = advancedOrders.length;
                  // Initialize array for tracking available orders.
                  availableOrders = new bool[](totalOrders);
                  // Skip overflow checks as all for loops are indexed starting at zero.
                  unchecked {
                      // Iterate over orders to ensure all considerations are met.
                      for (uint256 i = 0; i < totalOrders; ++i) {
                          // Retrieve the order in question.
                          AdvancedOrder memory advancedOrder = advancedOrders[i];
                          // Skip consideration item checks for order if not fulfilled.
                          if (advancedOrder.numerator == 0) {
                              // Note: orders do not need to be marked as unavailable as a
                              // new memory region has been allocated. Review carefully if
                              // altering compiler version or managing memory manually.
                              continue;
                          }
                          // Mark the order as available.
                          availableOrders[i] = true;
                          // Retrieve consideration items to ensure they are fulfilled.
                          ConsiderationItem[] memory consideration = (
                              advancedOrder.parameters.consideration
                          );
                          // Read length of consideration array and place on the stack.
                          uint256 totalConsiderationItems = consideration.length;
                          // Iterate over each consideration item to ensure it is met.
                          for (uint256 j = 0; j < totalConsiderationItems; ++j) {
                              // Retrieve remaining amount on the consideration item.
                              uint256 unmetAmount = consideration[j].startAmount;
                              // Revert if the remaining amount is not zero.
                              if (unmetAmount != 0) {
                                  revert ConsiderationNotMet(i, j, unmetAmount);
                              }
                          }
                      }
                  }
                  // Put ether value supplied by the caller on the stack.
                  uint256 etherRemaining = msg.value;
                  // Initialize an accumulator array. From this point forward, no new
                  // memory regions can be safely allocated until the accumulator is no
                  // longer being utilized, as the accumulator operates in an open-ended
                  // fashion from this memory pointer; existing memory may still be
                  // accessed and modified, however.
                  bytes memory accumulator = new bytes(AccumulatorDisarmed);
                  // Retrieve the length of the executions array and place on stack.
                  uint256 totalExecutions = executions.length;
                  // Iterate over each execution.
                  for (uint256 i = 0; i < totalExecutions; ) {
                      // Retrieve the execution and the associated received item.
                      Execution memory execution = executions[i];
                      ReceivedItem memory item = execution.item;
                      // If execution transfers native tokens, reduce value available.
                      if (item.itemType == ItemType.NATIVE) {
                          // Ensure that sufficient native tokens are still available.
                          if (item.amount > etherRemaining) {
                              revert InsufficientEtherSupplied();
                          }
                          // Skip underflow check as amount is less than ether remaining.
                          unchecked {
                              etherRemaining -= item.amount;
                          }
                      }
                      // Transfer the item specified by the execution.
                      _transfer(
                          item,
                          execution.offerer,
                          execution.conduitKey,
                          accumulator
                      );
                      // Skip overflow check as for loop is indexed starting at zero.
                      unchecked {
                          ++i;
                      }
                  }
                  // Trigger any remaining accumulated transfers via call to the conduit.
                  _triggerIfArmed(accumulator);
                  // If any ether remains after fulfillments, return it to the caller.
                  if (etherRemaining != 0) {
                      _transferEth(payable(msg.sender), etherRemaining);
                  }
                  // Clear the reentrancy guard.
                  _clearReentrancyGuard();
                  // Return the array containing available orders.
                  return (availableOrders);
              }
              /**
               * @dev Internal function to match an arbitrary number of full or partial
               *      orders, each with an arbitrary number of items for offer and
               *      consideration, supplying criteria resolvers containing specific
               *      token identifiers and associated proofs as well as fulfillments
               *      allocating offer components to consideration components.
               *
               * @param advancedOrders    The advanced orders to match. Note that both the
               *                          offerer and fulfiller on each order must first
               *                          approve this contract (or their conduit if
               *                          indicated by the order) to transfer any relevant
               *                          tokens on their behalf and each consideration
               *                          recipient must implement `onERC1155Received` in
               *                          order to receive ERC1155 tokens. Also note that
               *                          the offer and consideration components for each
               *                          order must have no remainder after multiplying
               *                          the respective amount with the supplied fraction
               *                          in order for the group of partial fills to be
               *                          considered valid.
               * @param criteriaResolvers An array where each element contains a reference
               *                          to a specific order as well as that order's
               *                          offer or consideration, a token identifier, and
               *                          a proof that the supplied token identifier is
               *                          contained in the order's merkle root. Note that
               *                          an empty root indicates that any (transferable)
               *                          token identifier is valid and that no associated
               *                          proof needs to be supplied.
               * @param fulfillments      An array of elements allocating offer components
               *                          to consideration components. Note that each
               *                          consideration component must be fully met in
               *                          order for the match operation to be valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function _matchAdvancedOrders(
                  AdvancedOrder[] memory advancedOrders,
                  CriteriaResolver[] memory criteriaResolvers,
                  Fulfillment[] calldata fulfillments
              ) internal returns (Execution[] memory executions) {
                  // Validate orders, update order status, and determine item amounts.
                  _validateOrdersAndPrepareToFulfill(
                      advancedOrders,
                      criteriaResolvers,
                      true, // Signifies that invalid orders should revert.
                      advancedOrders.length,
                      address(0) // OrderFulfilled event has no recipient when matching.
                  );
                  // Fulfill the orders using the supplied fulfillments.
                  return _fulfillAdvancedOrders(advancedOrders, fulfillments);
              }
              /**
               * @dev Internal function to fulfill an arbitrary number of orders, either
               *      full or partial, after validating, adjusting amounts, and applying
               *      criteria resolvers.
               *
               * @param advancedOrders     The orders to match, including a fraction to
               *                           attempt to fill for each order.
               * @param fulfillments       An array of elements allocating offer
               *                           components to consideration components. Note
               *                           that the final amount of each consideration
               *                           component must be zero for a match operation to
               *                           be considered valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function _fulfillAdvancedOrders(
                  AdvancedOrder[] memory advancedOrders,
                  Fulfillment[] calldata fulfillments
              ) internal returns (Execution[] memory executions) {
                  // Retrieve fulfillments array length and place on the stack.
                  uint256 totalFulfillments = fulfillments.length;
                  // Allocate executions by fulfillment and apply them to each execution.
                  executions = new Execution[](totalFulfillments);
                  // Skip overflow checks as all for loops are indexed starting at zero.
                  unchecked {
                      // Track number of filtered executions.
                      uint256 totalFilteredExecutions = 0;
                      // Iterate over each fulfillment.
                      for (uint256 i = 0; i < totalFulfillments; ++i) {
                          /// Retrieve the fulfillment in question.
                          Fulfillment calldata fulfillment = fulfillments[i];
                          // Derive the execution corresponding with the fulfillment.
                          Execution memory execution = _applyFulfillment(
                              advancedOrders,
                              fulfillment.offerComponents,
                              fulfillment.considerationComponents
                          );
                          // If offerer and recipient on the execution are the same...
                          if (execution.item.recipient == execution.offerer) {
                              // Increment total filtered executions.
                              ++totalFilteredExecutions;
                          } else {
                              // Otherwise, assign the execution to the executions array.
                              executions[i - totalFilteredExecutions] = execution;
                          }
                      }
                      // If some number of executions have been filtered...
                      if (totalFilteredExecutions != 0) {
                          // reduce the total length of the executions array.
                          assembly {
                              mstore(
                                  executions,
                                  sub(mload(executions), totalFilteredExecutions)
                              )
                          }
                      }
                  }
                  // Perform final checks and execute orders.
                  _performFinalChecksAndExecuteOrders(advancedOrders, executions);
                  // Return the executions array.
                  return (executions);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.13;
          // prettier-ignore
          import {
              ConsiderationInterface
          } from "../interfaces/ConsiderationInterface.sol";
          // prettier-ignore
          import {
              OrderComponents,
              BasicOrderParameters,
              OrderParameters,
              Order,
              AdvancedOrder,
              OrderStatus,
              CriteriaResolver,
              Fulfillment,
              FulfillmentComponent,
              Execution
          } from "./ConsiderationStructs.sol";
          import { OrderCombiner } from "./OrderCombiner.sol";
          /**
           * @title Consideration
           * @author 0age
           * @custom:coauthor d1ll0n
           * @custom:coauthor transmissions11
           * @custom:version 1.1
           * @notice Consideration is a generalized ETH/ERC20/ERC721/ERC1155 marketplace.
           *         It minimizes external calls to the greatest extent possible and
           *         provides lightweight methods for common routes as well as more
           *         flexible methods for composing advanced orders or groups of orders.
           *         Each order contains an arbitrary number of items that may be spent
           *         (the "offer") along with an arbitrary number of items that must be
           *         received back by the indicated recipients (the "consideration").
           */
          contract Consideration is ConsiderationInterface, OrderCombiner {
              /**
               * @notice Derive and set hashes, reference chainId, and associated domain
               *         separator during deployment.
               *
               * @param conduitController A contract that deploys conduits, or proxies
               *                          that may optionally be used to transfer approved
               *                          ERC20/721/1155 tokens.
               */
              constructor(address conduitController) OrderCombiner(conduitController) {}
              /**
               * @notice Fulfill an order offering an ERC20, ERC721, or ERC1155 item by
               *         supplying Ether (or other native tokens), ERC20 tokens, an ERC721
               *         item, or an ERC1155 item as consideration. Six permutations are
               *         supported: Native token to ERC721, Native token to ERC1155, ERC20
               *         to ERC721, ERC20 to ERC1155, ERC721 to ERC20, and ERC1155 to
               *         ERC20 (with native tokens supplied as msg.value). For an order to
               *         be eligible for fulfillment via this method, it must contain a
               *         single offer item (though that item may have a greater amount if
               *         the item is not an ERC721). An arbitrary number of "additional
               *         recipients" may also be supplied which will each receive native
               *         tokens or ERC20 items from the fulfiller as consideration. Refer
               *         to the documentation for a more comprehensive summary of how to
               *         utilize this method and what orders are compatible with it.
               *
               * @param parameters Additional information on the fulfilled order. Note
               *                   that the offerer and the fulfiller must first approve
               *                   this contract (or their chosen conduit if indicated)
               *                   before any tokens can be transferred. Also note that
               *                   contract recipients of ERC1155 consideration items must
               *                   implement `onERC1155Received` in order to receive those
               *                   items.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillBasicOrder(BasicOrderParameters calldata parameters)
                  external
                  payable
                  override
                  returns (bool fulfilled)
              {
                  // Validate and fulfill the basic order.
                  fulfilled = _validateAndFulfillBasicOrder(parameters);
              }
              /**
               * @notice Fulfill an order with an arbitrary number of items for offer and
               *         consideration. Note that this function does not support
               *         criteria-based orders or partial filling of orders (though
               *         filling the remainder of a partially-filled order is supported).
               *
               * @param order               The order to fulfill. Note that both the
               *                            offerer and the fulfiller must first approve
               *                            this contract (or the corresponding conduit if
               *                            indicated) to transfer any relevant tokens on
               *                            their behalf and that contracts must implement
               *                            `onERC1155Received` to receive ERC1155 tokens
               *                            as consideration.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used (and direct approvals set on
               *                            Consideration).
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillOrder(Order calldata order, bytes32 fulfillerConduitKey)
                  external
                  payable
                  override
                  returns (bool fulfilled)
              {
                  // Convert order to "advanced" order, then validate and fulfill it.
                  fulfilled = _validateAndFulfillAdvancedOrder(
                      _convertOrderToAdvanced(order),
                      new CriteriaResolver[](0), // No criteria resolvers supplied.
                      fulfillerConduitKey,
                      msg.sender
                  );
              }
              /**
               * @notice Fill an order, fully or partially, with an arbitrary number of
               *         items for offer and consideration alongside criteria resolvers
               *         containing specific token identifiers and associated proofs.
               *
               * @param advancedOrder       The order to fulfill along with the fraction
               *                            of the order to attempt to fill. Note that
               *                            both the offerer and the fulfiller must first
               *                            approve this contract (or their conduit if
               *                            indicated by the order) to transfer any
               *                            relevant tokens on their behalf and that
               *                            contracts must implement `onERC1155Received`
               *                            to receive ERC1155 tokens as consideration.
               *                            Also note that all offer and consideration
               *                            components must have no remainder after
               *                            multiplication of the respective amount with
               *                            the supplied fraction for the partial fill to
               *                            be considered valid.
               * @param criteriaResolvers   An array where each element contains a
               *                            reference to a specific offer or
               *                            consideration, a token identifier, and a proof
               *                            that the supplied token identifier is
               *                            contained in the merkle root held by the item
               *                            in question's criteria element. Note that an
               *                            empty criteria indicates that any
               *                            (transferable) token identifier on the token
               *                            in question is valid and that no associated
               *                            proof needs to be supplied.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used (and direct approvals set on
               *                            Consideration).
               * @param recipient           The intended recipient for all received items,
               *                            with `address(0)` indicating that the caller
               *                            should receive the items.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillAdvancedOrder(
                  AdvancedOrder calldata advancedOrder,
                  CriteriaResolver[] calldata criteriaResolvers,
                  bytes32 fulfillerConduitKey,
                  address recipient
              ) external payable override returns (bool fulfilled) {
                  // Validate and fulfill the order.
                  fulfilled = _validateAndFulfillAdvancedOrder(
                      advancedOrder,
                      criteriaResolvers,
                      fulfillerConduitKey,
                      recipient == address(0) ? msg.sender : recipient
                  );
              }
              /**
               * @notice Attempt to fill a group of orders, each with an arbitrary number
               *         of items for offer and consideration. Any order that is not
               *         currently active, has already been fully filled, or has been
               *         cancelled will be omitted. Remaining offer and consideration
               *         items will then be aggregated where possible as indicated by the
               *         supplied offer and consideration component arrays and aggregated
               *         items will be transferred to the fulfiller or to each intended
               *         recipient, respectively. Note that a failing item transfer or an
               *         issue with order formatting will cause the entire batch to fail.
               *         Note that this function does not support criteria-based orders or
               *         partial filling of orders (though filling the remainder of a
               *         partially-filled order is supported).
               *
               * @param orders                    The orders to fulfill. Note that both
               *                                  the offerer and the fulfiller must first
               *                                  approve this contract (or the
               *                                  corresponding conduit if indicated) to
               *                                  transfer any relevant tokens on their
               *                                  behalf and that contracts must implement
               *                                  `onERC1155Received` to receive ERC1155
               *                                  tokens as consideration.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used (and
               *                                  direct approvals set on Consideration).
               * @param maximumFulfilled          The maximum number of orders to fulfill.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function fulfillAvailableOrders(
                  Order[] calldata orders,
                  FulfillmentComponent[][] calldata offerFulfillments,
                  FulfillmentComponent[][] calldata considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  uint256 maximumFulfilled
              )
                  external
                  payable
                  override
                  returns (bool[] memory availableOrders, Execution[] memory executions)
              {
                  // Convert orders to "advanced" orders and fulfill all available orders.
                  return
                      _fulfillAvailableAdvancedOrders(
                          _convertOrdersToAdvanced(orders), // Convert to advanced orders.
                          new CriteriaResolver[](0), // No criteria resolvers supplied.
                          offerFulfillments,
                          considerationFulfillments,
                          fulfillerConduitKey,
                          msg.sender,
                          maximumFulfilled
                      );
              }
              /**
               * @notice Attempt to fill a group of orders, fully or partially, with an
               *         arbitrary number of items for offer and consideration per order
               *         alongside criteria resolvers containing specific token
               *         identifiers and associated proofs. Any order that is not
               *         currently active, has already been fully filled, or has been
               *         cancelled will be omitted. Remaining offer and consideration
               *         items will then be aggregated where possible as indicated by the
               *         supplied offer and consideration component arrays and aggregated
               *         items will be transferred to the fulfiller or to each intended
               *         recipient, respectively. Note that a failing item transfer or an
               *         issue with order formatting will cause the entire batch to fail.
               *
               * @param advancedOrders            The orders to fulfill along with the
               *                                  fraction of those orders to attempt to
               *                                  fill. Note that both the offerer and the
               *                                  fulfiller must first approve this
               *                                  contract (or their conduit if indicated
               *                                  by the order) to transfer any relevant
               *                                  tokens on their behalf and that
               *                                  contracts must implement
               *                                  `onERC1155Received` in order to receive
               *                                  ERC1155 tokens as consideration. Also
               *                                  note that all offer and consideration
               *                                  components must have no remainder after
               *                                  multiplication of the respective amount
               *                                  with the supplied fraction for an
               *                                  order's partial fill amount to be
               *                                  considered valid.
               * @param criteriaResolvers         An array where each element contains a
               *                                  reference to a specific offer or
               *                                  consideration, a token identifier, and a
               *                                  proof that the supplied token identifier
               *                                  is contained in the merkle root held by
               *                                  the item in question's criteria element.
               *                                  Note that an empty criteria indicates
               *                                  that any (transferable) token
               *                                  identifier on the token in question is
               *                                  valid and that no associated proof needs
               *                                  to be supplied.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used (and
               *                                  direct approvals set on Consideration).
               * @param recipient                 The intended recipient for all received
               *                                  items, with `address(0)` indicating that
               *                                  the caller should receive the items.
               * @param maximumFulfilled          The maximum number of orders to fulfill.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function fulfillAvailableAdvancedOrders(
                  AdvancedOrder[] memory advancedOrders,
                  CriteriaResolver[] calldata criteriaResolvers,
                  FulfillmentComponent[][] calldata offerFulfillments,
                  FulfillmentComponent[][] calldata considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  address recipient,
                  uint256 maximumFulfilled
              )
                  external
                  payable
                  override
                  returns (bool[] memory availableOrders, Execution[] memory executions)
              {
                  // Fulfill all available orders.
                  return
                      _fulfillAvailableAdvancedOrders(
                          advancedOrders,
                          criteriaResolvers,
                          offerFulfillments,
                          considerationFulfillments,
                          fulfillerConduitKey,
                          recipient == address(0) ? msg.sender : recipient,
                          maximumFulfilled
                      );
              }
              /**
               * @notice Match an arbitrary number of orders, each with an arbitrary
               *         number of items for offer and consideration along with a set of
               *         fulfillments allocating offer components to consideration
               *         components. Note that this function does not support
               *         criteria-based or partial filling of orders (though filling the
               *         remainder of a partially-filled order is supported).
               *
               * @param orders            The orders to match. Note that both the offerer
               *                          and fulfiller on each order must first approve
               *                          this contract (or their conduit if indicated by
               *                          the order) to transfer any relevant tokens on
               *                          their behalf and each consideration recipient
               *                          must implement `onERC1155Received` in order to
               *                          receive ERC1155 tokens.
               * @param fulfillments      An array of elements allocating offer components
               *                          to consideration components. Note that each
               *                          consideration component must be fully met in
               *                          order for the match operation to be valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function matchOrders(
                  Order[] calldata orders,
                  Fulfillment[] calldata fulfillments
              ) external payable override returns (Execution[] memory executions) {
                  // Convert to advanced, validate, and match orders using fulfillments.
                  return
                      _matchAdvancedOrders(
                          _convertOrdersToAdvanced(orders),
                          new CriteriaResolver[](0), // No criteria resolvers supplied.
                          fulfillments
                      );
              }
              /**
               * @notice Match an arbitrary number of full or partial orders, each with an
               *         arbitrary number of items for offer and consideration, supplying
               *         criteria resolvers containing specific token identifiers and
               *         associated proofs as well as fulfillments allocating offer
               *         components to consideration components.
               *
               * @param advancedOrders    The advanced orders to match. Note that both the
               *                          offerer and fulfiller on each order must first
               *                          approve this contract (or their conduit if
               *                          indicated by the order) to transfer any relevant
               *                          tokens on their behalf and each consideration
               *                          recipient must implement `onERC1155Received` in
               *                          order to receive ERC1155 tokens. Also note that
               *                          the offer and consideration components for each
               *                          order must have no remainder after multiplying
               *                          the respective amount with the supplied fraction
               *                          in order for the group of partial fills to be
               *                          considered valid.
               * @param criteriaResolvers An array where each element contains a reference
               *                          to a specific order as well as that order's
               *                          offer or consideration, a token identifier, and
               *                          a proof that the supplied token identifier is
               *                          contained in the order's merkle root. Note that
               *                          an empty root indicates that any (transferable)
               *                          token identifier is valid and that no associated
               *                          proof needs to be supplied.
               * @param fulfillments      An array of elements allocating offer components
               *                          to consideration components. Note that each
               *                          consideration component must be fully met in
               *                          order for the match operation to be valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function matchAdvancedOrders(
                  AdvancedOrder[] memory advancedOrders,
                  CriteriaResolver[] calldata criteriaResolvers,
                  Fulfillment[] calldata fulfillments
              ) external payable override returns (Execution[] memory executions) {
                  // Validate and match the advanced orders using supplied fulfillments.
                  return
                      _matchAdvancedOrders(
                          advancedOrders,
                          criteriaResolvers,
                          fulfillments
                      );
              }
              /**
               * @notice Cancel an arbitrary number of orders. Note that only the offerer
               *         or the zone of a given order may cancel it. Callers should ensure
               *         that the intended order was cancelled by calling `getOrderStatus`
               *         and confirming that `isCancelled` returns `true`.
               *
               * @param orders The orders to cancel.
               *
               * @return cancelled A boolean indicating whether the supplied orders have
               *                   been successfully cancelled.
               */
              function cancel(OrderComponents[] calldata orders)
                  external
                  override
                  returns (bool cancelled)
              {
                  // Cancel the orders.
                  cancelled = _cancel(orders);
              }
              /**
               * @notice Validate an arbitrary number of orders, thereby registering their
               *         signatures as valid and allowing the fulfiller to skip signature
               *         verification on fulfillment. Note that validated orders may still
               *         be unfulfillable due to invalid item amounts or other factors;
               *         callers should determine whether validated orders are fulfillable
               *         by simulating the fulfillment call prior to execution. Also note
               *         that anyone can validate a signed order, but only the offerer can
               *         validate an order without supplying a signature.
               *
               * @param orders The orders to validate.
               *
               * @return validated A boolean indicating whether the supplied orders have
               *                   been successfully validated.
               */
              function validate(Order[] calldata orders)
                  external
                  override
                  returns (bool validated)
              {
                  // Validate the orders.
                  validated = _validate(orders);
              }
              /**
               * @notice Cancel all orders from a given offerer with a given zone in bulk
               *         by incrementing a counter. Note that only the offerer may
               *         increment the counter.
               *
               * @return newCounter The new counter.
               */
              function incrementCounter() external override returns (uint256 newCounter) {
                  // Increment current counter for the supplied offerer.
                  newCounter = _incrementCounter();
              }
              /**
               * @notice Retrieve the order hash for a given order.
               *
               * @param order The components of the order.
               *
               * @return orderHash The order hash.
               */
              function getOrderHash(OrderComponents calldata order)
                  external
                  view
                  override
                  returns (bytes32 orderHash)
              {
                  // Derive order hash by supplying order parameters along with counter.
                  orderHash = _deriveOrderHash(
                      OrderParameters(
                          order.offerer,
                          order.zone,
                          order.offer,
                          order.consideration,
                          order.orderType,
                          order.startTime,
                          order.endTime,
                          order.zoneHash,
                          order.salt,
                          order.conduitKey,
                          order.consideration.length
                      ),
                      order.counter
                  );
              }
              /**
               * @notice Retrieve the status of a given order by hash, including whether
               *         the order has been cancelled or validated and the fraction of the
               *         order that has been filled.
               *
               * @param orderHash The order hash in question.
               *
               * @return isValidated A boolean indicating whether the order in question
               *                     has been validated (i.e. previously approved or
               *                     partially filled).
               * @return isCancelled A boolean indicating whether the order in question
               *                     has been cancelled.
               * @return totalFilled The total portion of the order that has been filled
               *                     (i.e. the "numerator").
               * @return totalSize   The total size of the order that is either filled or
               *                     unfilled (i.e. the "denominator").
               */
              function getOrderStatus(bytes32 orderHash)
                  external
                  view
                  override
                  returns (
                      bool isValidated,
                      bool isCancelled,
                      uint256 totalFilled,
                      uint256 totalSize
                  )
              {
                  // Retrieve the order status using the order hash.
                  return _getOrderStatus(orderHash);
              }
              /**
               * @notice Retrieve the current counter for a given offerer.
               *
               * @param offerer The offerer in question.
               *
               * @return counter The current counter.
               */
              function getCounter(address offerer)
                  external
                  view
                  override
                  returns (uint256 counter)
              {
                  // Return the counter for the supplied offerer.
                  counter = _getCounter(offerer);
              }
              /**
               * @notice Retrieve configuration information for this contract.
               *
               * @return version           The contract version.
               * @return domainSeparator   The domain separator for this contract.
               * @return conduitController The conduit Controller set for this contract.
               */
              function information()
                  external
                  view
                  override
                  returns (
                      string memory version,
                      bytes32 domainSeparator,
                      address conduitController
                  )
              {
                  // Return the information for this contract.
                  return _information();
              }
              /**
               * @notice Retrieve the name of this contract.
               *
               * @return contractName The name of this contract.
               */
              function name()
                  external
                  pure
                  override
                  returns (string memory contractName)
              {
                  // Return the name of the contract.
                  contractName = _name();
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // prettier-ignore
          import {
              BasicOrderParameters,
              OrderComponents,
              Fulfillment,
              FulfillmentComponent,
              Execution,
              Order,
              AdvancedOrder,
              OrderStatus,
              CriteriaResolver
          } from "../lib/ConsiderationStructs.sol";
          /**
           * @title ConsiderationInterface
           * @author 0age
           * @custom:version 1.1
           * @notice Consideration is a generalized ETH/ERC20/ERC721/ERC1155 marketplace.
           *         It minimizes external calls to the greatest extent possible and
           *         provides lightweight methods for common routes as well as more
           *         flexible methods for composing advanced orders.
           *
           * @dev ConsiderationInterface contains all external function interfaces for
           *      Consideration.
           */
          interface ConsiderationInterface {
              /**
               * @notice Fulfill an order offering an ERC721 token by supplying Ether (or
               *         the native token for the given chain) as consideration for the
               *         order. An arbitrary number of "additional recipients" may also be
               *         supplied which will each receive native tokens from the fulfiller
               *         as consideration.
               *
               * @param parameters Additional information on the fulfilled order. Note
               *                   that the offerer must first approve this contract (or
               *                   their preferred conduit if indicated by the order) for
               *                   their offered ERC721 token to be transferred.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillBasicOrder(BasicOrderParameters calldata parameters)
                  external
                  payable
                  returns (bool fulfilled);
              /**
               * @notice Fulfill an order with an arbitrary number of items for offer and
               *         consideration. Note that this function does not support
               *         criteria-based orders or partial filling of orders (though
               *         filling the remainder of a partially-filled order is supported).
               *
               * @param order               The order to fulfill. Note that both the
               *                            offerer and the fulfiller must first approve
               *                            this contract (or the corresponding conduit if
               *                            indicated) to transfer any relevant tokens on
               *                            their behalf and that contracts must implement
               *                            `onERC1155Received` to receive ERC1155 tokens
               *                            as consideration.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used, with direct approvals set on
               *                            Consideration.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillOrder(Order calldata order, bytes32 fulfillerConduitKey)
                  external
                  payable
                  returns (bool fulfilled);
              /**
               * @notice Fill an order, fully or partially, with an arbitrary number of
               *         items for offer and consideration alongside criteria resolvers
               *         containing specific token identifiers and associated proofs.
               *
               * @param advancedOrder       The order to fulfill along with the fraction
               *                            of the order to attempt to fill. Note that
               *                            both the offerer and the fulfiller must first
               *                            approve this contract (or their preferred
               *                            conduit if indicated by the order) to transfer
               *                            any relevant tokens on their behalf and that
               *                            contracts must implement `onERC1155Received`
               *                            to receive ERC1155 tokens as consideration.
               *                            Also note that all offer and consideration
               *                            components must have no remainder after
               *                            multiplication of the respective amount with
               *                            the supplied fraction for the partial fill to
               *                            be considered valid.
               * @param criteriaResolvers   An array where each element contains a
               *                            reference to a specific offer or
               *                            consideration, a token identifier, and a proof
               *                            that the supplied token identifier is
               *                            contained in the merkle root held by the item
               *                            in question's criteria element. Note that an
               *                            empty criteria indicates that any
               *                            (transferable) token identifier on the token
               *                            in question is valid and that no associated
               *                            proof needs to be supplied.
               * @param fulfillerConduitKey A bytes32 value indicating what conduit, if
               *                            any, to source the fulfiller's token approvals
               *                            from. The zero hash signifies that no conduit
               *                            should be used, with direct approvals set on
               *                            Consideration.
               * @param recipient           The intended recipient for all received items,
               *                            with `address(0)` indicating that the caller
               *                            should receive the items.
               *
               * @return fulfilled A boolean indicating whether the order has been
               *                   successfully fulfilled.
               */
              function fulfillAdvancedOrder(
                  AdvancedOrder calldata advancedOrder,
                  CriteriaResolver[] calldata criteriaResolvers,
                  bytes32 fulfillerConduitKey,
                  address recipient
              ) external payable returns (bool fulfilled);
              /**
               * @notice Attempt to fill a group of orders, each with an arbitrary number
               *         of items for offer and consideration. Any order that is not
               *         currently active, has already been fully filled, or has been
               *         cancelled will be omitted. Remaining offer and consideration
               *         items will then be aggregated where possible as indicated by the
               *         supplied offer and consideration component arrays and aggregated
               *         items will be transferred to the fulfiller or to each intended
               *         recipient, respectively. Note that a failing item transfer or an
               *         issue with order formatting will cause the entire batch to fail.
               *         Note that this function does not support criteria-based orders or
               *         partial filling of orders (though filling the remainder of a
               *         partially-filled order is supported).
               *
               * @param orders                    The orders to fulfill. Note that both
               *                                  the offerer and the fulfiller must first
               *                                  approve this contract (or the
               *                                  corresponding conduit if indicated) to
               *                                  transfer any relevant tokens on their
               *                                  behalf and that contracts must implement
               *                                  `onERC1155Received` to receive ERC1155
               *                                  tokens as consideration.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used, with
               *                                  direct approvals set on this contract.
               * @param maximumFulfilled          The maximum number of orders to fulfill.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function fulfillAvailableOrders(
                  Order[] calldata orders,
                  FulfillmentComponent[][] calldata offerFulfillments,
                  FulfillmentComponent[][] calldata considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  uint256 maximumFulfilled
              )
                  external
                  payable
                  returns (bool[] memory availableOrders, Execution[] memory executions);
              /**
               * @notice Attempt to fill a group of orders, fully or partially, with an
               *         arbitrary number of items for offer and consideration per order
               *         alongside criteria resolvers containing specific token
               *         identifiers and associated proofs. Any order that is not
               *         currently active, has already been fully filled, or has been
               *         cancelled will be omitted. Remaining offer and consideration
               *         items will then be aggregated where possible as indicated by the
               *         supplied offer and consideration component arrays and aggregated
               *         items will be transferred to the fulfiller or to each intended
               *         recipient, respectively. Note that a failing item transfer or an
               *         issue with order formatting will cause the entire batch to fail.
               *
               * @param advancedOrders            The orders to fulfill along with the
               *                                  fraction of those orders to attempt to
               *                                  fill. Note that both the offerer and the
               *                                  fulfiller must first approve this
               *                                  contract (or their preferred conduit if
               *                                  indicated by the order) to transfer any
               *                                  relevant tokens on their behalf and that
               *                                  contracts must implement
               *                                  `onERC1155Received` to enable receipt of
               *                                  ERC1155 tokens as consideration. Also
               *                                  note that all offer and consideration
               *                                  components must have no remainder after
               *                                  multiplication of the respective amount
               *                                  with the supplied fraction for an
               *                                  order's partial fill amount to be
               *                                  considered valid.
               * @param criteriaResolvers         An array where each element contains a
               *                                  reference to a specific offer or
               *                                  consideration, a token identifier, and a
               *                                  proof that the supplied token identifier
               *                                  is contained in the merkle root held by
               *                                  the item in question's criteria element.
               *                                  Note that an empty criteria indicates
               *                                  that any (transferable) token
               *                                  identifier on the token in question is
               *                                  valid and that no associated proof needs
               *                                  to be supplied.
               * @param offerFulfillments         An array of FulfillmentComponent arrays
               *                                  indicating which offer items to attempt
               *                                  to aggregate when preparing executions.
               * @param considerationFulfillments An array of FulfillmentComponent arrays
               *                                  indicating which consideration items to
               *                                  attempt to aggregate when preparing
               *                                  executions.
               * @param fulfillerConduitKey       A bytes32 value indicating what conduit,
               *                                  if any, to source the fulfiller's token
               *                                  approvals from. The zero hash signifies
               *                                  that no conduit should be used, with
               *                                  direct approvals set on this contract.
               * @param recipient                 The intended recipient for all received
               *                                  items, with `address(0)` indicating that
               *                                  the caller should receive the items.
               * @param maximumFulfilled          The maximum number of orders to fulfill.
               *
               * @return availableOrders An array of booleans indicating if each order
               *                         with an index corresponding to the index of the
               *                         returned boolean was fulfillable or not.
               * @return executions      An array of elements indicating the sequence of
               *                         transfers performed as part of matching the given
               *                         orders.
               */
              function fulfillAvailableAdvancedOrders(
                  AdvancedOrder[] calldata advancedOrders,
                  CriteriaResolver[] calldata criteriaResolvers,
                  FulfillmentComponent[][] calldata offerFulfillments,
                  FulfillmentComponent[][] calldata considerationFulfillments,
                  bytes32 fulfillerConduitKey,
                  address recipient,
                  uint256 maximumFulfilled
              )
                  external
                  payable
                  returns (bool[] memory availableOrders, Execution[] memory executions);
              /**
               * @notice Match an arbitrary number of orders, each with an arbitrary
               *         number of items for offer and consideration along with as set of
               *         fulfillments allocating offer components to consideration
               *         components. Note that this function does not support
               *         criteria-based or partial filling of orders (though filling the
               *         remainder of a partially-filled order is supported).
               *
               * @param orders       The orders to match. Note that both the offerer and
               *                     fulfiller on each order must first approve this
               *                     contract (or their conduit if indicated by the order)
               *                     to transfer any relevant tokens on their behalf and
               *                     each consideration recipient must implement
               *                     `onERC1155Received` to enable ERC1155 token receipt.
               * @param fulfillments An array of elements allocating offer components to
               *                     consideration components. Note that each
               *                     consideration component must be fully met for the
               *                     match operation to be valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function matchOrders(
                  Order[] calldata orders,
                  Fulfillment[] calldata fulfillments
              ) external payable returns (Execution[] memory executions);
              /**
               * @notice Match an arbitrary number of full or partial orders, each with an
               *         arbitrary number of items for offer and consideration, supplying
               *         criteria resolvers containing specific token identifiers and
               *         associated proofs as well as fulfillments allocating offer
               *         components to consideration components.
               *
               * @param orders            The advanced orders to match. Note that both the
               *                          offerer and fulfiller on each order must first
               *                          approve this contract (or a preferred conduit if
               *                          indicated by the order) to transfer any relevant
               *                          tokens on their behalf and each consideration
               *                          recipient must implement `onERC1155Received` in
               *                          order to receive ERC1155 tokens. Also note that
               *                          the offer and consideration components for each
               *                          order must have no remainder after multiplying
               *                          the respective amount with the supplied fraction
               *                          in order for the group of partial fills to be
               *                          considered valid.
               * @param criteriaResolvers An array where each element contains a reference
               *                          to a specific order as well as that order's
               *                          offer or consideration, a token identifier, and
               *                          a proof that the supplied token identifier is
               *                          contained in the order's merkle root. Note that
               *                          an empty root indicates that any (transferable)
               *                          token identifier is valid and that no associated
               *                          proof needs to be supplied.
               * @param fulfillments      An array of elements allocating offer components
               *                          to consideration components. Note that each
               *                          consideration component must be fully met in
               *                          order for the match operation to be valid.
               *
               * @return executions An array of elements indicating the sequence of
               *                    transfers performed as part of matching the given
               *                    orders.
               */
              function matchAdvancedOrders(
                  AdvancedOrder[] calldata orders,
                  CriteriaResolver[] calldata criteriaResolvers,
                  Fulfillment[] calldata fulfillments
              ) external payable returns (Execution[] memory executions);
              /**
               * @notice Cancel an arbitrary number of orders. Note that only the offerer
               *         or the zone of a given order may cancel it. Callers should ensure
               *         that the intended order was cancelled by calling `getOrderStatus`
               *         and confirming that `isCancelled` returns `true`.
               *
               * @param orders The orders to cancel.
               *
               * @return cancelled A boolean indicating whether the supplied orders have
               *                   been successfully cancelled.
               */
              function cancel(OrderComponents[] calldata orders)
                  external
                  returns (bool cancelled);
              /**
               * @notice Validate an arbitrary number of orders, thereby registering their
               *         signatures as valid and allowing the fulfiller to skip signature
               *         verification on fulfillment. Note that validated orders may still
               *         be unfulfillable due to invalid item amounts or other factors;
               *         callers should determine whether validated orders are fulfillable
               *         by simulating the fulfillment call prior to execution. Also note
               *         that anyone can validate a signed order, but only the offerer can
               *         validate an order without supplying a signature.
               *
               * @param orders The orders to validate.
               *
               * @return validated A boolean indicating whether the supplied orders have
               *                   been successfully validated.
               */
              function validate(Order[] calldata orders)
                  external
                  returns (bool validated);
              /**
               * @notice Cancel all orders from a given offerer with a given zone in bulk
               *         by incrementing a counter. Note that only the offerer may
               *         increment the counter.
               *
               * @return newCounter The new counter.
               */
              function incrementCounter() external returns (uint256 newCounter);
              /**
               * @notice Retrieve the order hash for a given order.
               *
               * @param order The components of the order.
               *
               * @return orderHash The order hash.
               */
              function getOrderHash(OrderComponents calldata order)
                  external
                  view
                  returns (bytes32 orderHash);
              /**
               * @notice Retrieve the status of a given order by hash, including whether
               *         the order has been cancelled or validated and the fraction of the
               *         order that has been filled.
               *
               * @param orderHash The order hash in question.
               *
               * @return isValidated A boolean indicating whether the order in question
               *                     has been validated (i.e. previously approved or
               *                     partially filled).
               * @return isCancelled A boolean indicating whether the order in question
               *                     has been cancelled.
               * @return totalFilled The total portion of the order that has been filled
               *                     (i.e. the "numerator").
               * @return totalSize   The total size of the order that is either filled or
               *                     unfilled (i.e. the "denominator").
               */
              function getOrderStatus(bytes32 orderHash)
                  external
                  view
                  returns (
                      bool isValidated,
                      bool isCancelled,
                      uint256 totalFilled,
                      uint256 totalSize
                  );
              /**
               * @notice Retrieve the current counter for a given offerer.
               *
               * @param offerer The offerer in question.
               *
               * @return counter The current counter.
               */
              function getCounter(address offerer)
                  external
                  view
                  returns (uint256 counter);
              /**
               * @notice Retrieve configuration information for this contract.
               *
               * @return version           The contract version.
               * @return domainSeparator   The domain separator for this contract.
               * @return conduitController The conduit Controller set for this contract.
               */
              function information()
                  external
                  view
                  returns (
                      string memory version,
                      bytes32 domainSeparator,
                      address conduitController
                  );
              /**
               * @notice Retrieve the name of this contract.
               *
               * @return contractName The name of this contract.
               */
              function name() external view returns (string memory contractName);
          }
          

          File 2 of 5: ERC721DropProxy
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          
          // OpenZeppelin Contracts v4.4.1 (proxy/ERC1967/ERC1967Proxy.sol)
          
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/Proxy.sol)
          
          /**
           * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
           * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
           * be specified by overriding the virtual {_implementation} function.
           *
           * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
           * different contract through the {_delegate} function.
           *
           * The success and return data of the delegated call will be returned back to the caller of the proxy.
           */
          abstract contract Proxy {
              /**
               * @dev Delegates the current call to `implementation`.
               *
               * This function does not return to its internal call site, it will return directly to the external caller.
               */
              function _delegate(address implementation) internal virtual {
                  assembly {
                      // Copy msg.data. We take full control of memory in this inline assembly
                      // block because it will not return to Solidity code. We overwrite the
                      // Solidity scratch pad at memory position 0.
                      calldatacopy(0, 0, calldatasize())
          
                      // Call the implementation.
                      // out and outsize are 0 because we don't know the size yet.
                      let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
          
                      // Copy the returned data.
                      returndatacopy(0, 0, returndatasize())
          
                      switch result
                      // delegatecall returns 0 on error.
                      case 0 {
                          revert(0, returndatasize())
                      }
                      default {
                          return(0, returndatasize())
                      }
                  }
              }
          
              /**
               * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
               * and {_fallback} should delegate.
               */
              function _implementation() internal view virtual returns (address);
          
              /**
               * @dev Delegates the current call to the address returned by `_implementation()`.
               *
               * This function does not return to its internal call site, it will return directly to the external caller.
               */
              function _fallback() internal virtual {
                  _beforeFallback();
                  _delegate(_implementation());
              }
          
              /**
               * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
               * function in the contract matches the call data.
               */
              fallback() external payable virtual {
                  _fallback();
              }
          
              /**
               * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
               * is empty.
               */
              receive() external payable virtual {
                  _fallback();
              }
          
              /**
               * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
               * call, or as part of the Solidity `fallback` or `receive` functions.
               *
               * If overriden should call `super._beforeFallback()`.
               */
              function _beforeFallback() internal virtual {}
          }
          
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
          
          // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
          
          /**
           * @dev This is the interface that {BeaconProxy} expects of its beacon.
           */
          interface IBeacon {
              /**
               * @dev Must return an address that can be used as a delegate call target.
               *
               * {BeaconProxy} will check that this address is a contract.
               */
              function implementation() external view returns (address);
          }
          
          // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
          
          /**
           * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
           * proxy whose upgrades are fully controlled by the current implementation.
           */
          interface IERC1822Proxiable {
              /**
               * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
               * address.
               *
               * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
               * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
               * function revert if invoked through a proxy.
               */
              function proxiableUUID() external view returns (bytes32);
          }
          
          // OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)
          
          /**
           * @dev Collection of functions related to the address type
           */
          library Address {
              /**
               * @dev Returns true if `account` is a contract.
               *
               * [IMPORTANT]
               * ====
               * It is unsafe to assume that an address for which this function returns
               * false is an externally-owned account (EOA) and not a contract.
               *
               * Among others, `isContract` will return false for the following
               * types of addresses:
               *
               *  - an externally-owned account
               *  - a contract in construction
               *  - an address where a contract will be created
               *  - an address where a contract lived, but was destroyed
               * ====
               *
               * [IMPORTANT]
               * ====
               * You shouldn't rely on `isContract` to protect against flash loan attacks!
               *
               * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
               * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
               * constructor.
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize/address.code.length, which returns 0
                  // for contracts in construction, since the code is only stored at the end
                  // of the constructor execution.
          
                  return account.code.length > 0;
              }
          
              /**
               * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
               * `recipient`, forwarding all available gas and reverting on errors.
               *
               * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
               * of certain opcodes, possibly making contracts go over the 2300 gas limit
               * imposed by `transfer`, making them unable to receive funds via
               * `transfer`. {sendValue} removes this limitation.
               *
               * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
               *
               * IMPORTANT: because control is transferred to `recipient`, care must be
               * taken to not create reentrancy vulnerabilities. Consider using
               * {ReentrancyGuard} or the
               * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
               */
              function sendValue(address payable recipient, uint256 amount) internal {
                  require(address(this).balance >= amount, "Address: insufficient balance");
          
                  (bool success, ) = recipient.call{value: amount}("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
          
              /**
               * @dev Performs a Solidity function call using a low level `call`. A
               * plain `call` is an unsafe replacement for a function call: use this
               * function instead.
               *
               * If `target` reverts with a revert reason, it is bubbled up by this
               * function (like regular Solidity function calls).
               *
               * Returns the raw returned data. To convert to the expected return value,
               * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
               *
               * Requirements:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionCall(target, data, "Address: low-level call failed");
              }
          
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
          
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
          
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  require(isContract(target), "Address: call to non-contract");
          
                  (bool success, bytes memory returndata) = target.call{value: value}(data);
                  return verifyCallResult(success, returndata, errorMessage);
              }
          
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
          
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  require(isContract(target), "Address: static call to non-contract");
          
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return verifyCallResult(success, returndata, errorMessage);
              }
          
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionDelegateCall(target, data, "Address: low-level delegate call failed");
              }
          
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  require(isContract(target), "Address: delegate call to non-contract");
          
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return verifyCallResult(success, returndata, errorMessage);
              }
          
              /**
               * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
               * revert reason using the provided one.
               *
               * _Available since v4.3._
               */
              function verifyCallResult(
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal pure returns (bytes memory) {
                  if (success) {
                      return returndata;
                  } else {
                      // Look for revert reason and bubble it up if present
                      if (returndata.length > 0) {
                          // The easiest way to bubble the revert reason is using memory via assembly
          
                          assembly {
                              let returndata_size := mload(returndata)
                              revert(add(32, returndata), returndata_size)
                          }
                      } else {
                          revert(errorMessage);
                      }
                  }
              }
          }
          
          // OpenZeppelin Contracts v4.4.1 (utils/StorageSlot.sol)
          
          /**
           * @dev Library for reading and writing primitive types to specific storage slots.
           *
           * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
           * This library helps with reading and writing to such slots without the need for inline assembly.
           *
           * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
           *
           * Example usage to set ERC1967 implementation slot:
           * ```
           * contract ERC1967 {
           *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
           *
           *     function _getImplementation() internal view returns (address) {
           *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
           *     }
           *
           *     function _setImplementation(address newImplementation) internal {
           *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
           *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
           *     }
           * }
           * ```
           *
           * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
           */
          library StorageSlot {
              struct AddressSlot {
                  address value;
              }
          
              struct BooleanSlot {
                  bool value;
              }
          
              struct Bytes32Slot {
                  bytes32 value;
              }
          
              struct Uint256Slot {
                  uint256 value;
              }
          
              /**
               * @dev Returns an `AddressSlot` with member `value` located at `slot`.
               */
              function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
          
              /**
               * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
               */
              function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
          
              /**
               * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
               */
              function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
          
              /**
               * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
               */
              function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
          }
          
          /**
           * @dev This abstract contract provides getters and event emitting update functions for
           * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
           *
           * _Available since v4.1._
           *
           * @custom:oz-upgrades-unsafe-allow delegatecall
           */
          abstract contract ERC1967Upgrade {
              // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
              bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
          
              /**
               * @dev Storage slot with the address of the current implementation.
               * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
          
              /**
               * @dev Emitted when the implementation is upgraded.
               */
              event Upgraded(address indexed implementation);
          
              /**
               * @dev Returns the current implementation address.
               */
              function _getImplementation() internal view returns (address) {
                  return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
              }
          
              /**
               * @dev Stores a new address in the EIP1967 implementation slot.
               */
              function _setImplementation(address newImplementation) private {
                  require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                  StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
              }
          
              /**
               * @dev Perform implementation upgrade
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeTo(address newImplementation) internal {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
              }
          
              /**
               * @dev Perform implementation upgrade with additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCall(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _upgradeTo(newImplementation);
                  if (data.length > 0 || forceCall) {
                      Address.functionDelegateCall(newImplementation, data);
                  }
              }
          
              /**
               * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCallUUPS(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  // Upgrades from old implementations will perform a rollback test. This test requires the new
                  // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                  // this special case will break upgrade paths from old UUPS implementation to new ones.
                  if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
                      _setImplementation(newImplementation);
                  } else {
                      try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                          require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                      } catch {
                          revert("ERC1967Upgrade: new implementation is not UUPS");
                      }
                      _upgradeToAndCall(newImplementation, data, forceCall);
                  }
              }
          
              /**
               * @dev Storage slot with the admin of the contract.
               * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
          
              /**
               * @dev Emitted when the admin account has changed.
               */
              event AdminChanged(address previousAdmin, address newAdmin);
          
              /**
               * @dev Returns the current admin.
               */
              function _getAdmin() internal view returns (address) {
                  return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
              }
          
              /**
               * @dev Stores a new address in the EIP1967 admin slot.
               */
              function _setAdmin(address newAdmin) private {
                  require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                  StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
              }
          
              /**
               * @dev Changes the admin of the proxy.
               *
               * Emits an {AdminChanged} event.
               */
              function _changeAdmin(address newAdmin) internal {
                  emit AdminChanged(_getAdmin(), newAdmin);
                  _setAdmin(newAdmin);
              }
          
              /**
               * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
               * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
               */
              bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
          
              /**
               * @dev Emitted when the beacon is upgraded.
               */
              event BeaconUpgraded(address indexed beacon);
          
              /**
               * @dev Returns the current beacon.
               */
              function _getBeacon() internal view returns (address) {
                  return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
              }
          
              /**
               * @dev Stores a new beacon in the EIP1967 beacon slot.
               */
              function _setBeacon(address newBeacon) private {
                  require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                  require(
                      Address.isContract(IBeacon(newBeacon).implementation()),
                      "ERC1967: beacon implementation is not a contract"
                  );
                  StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
              }
          
              /**
               * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
               * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
               *
               * Emits a {BeaconUpgraded} event.
               */
              function _upgradeBeaconToAndCall(
                  address newBeacon,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _setBeacon(newBeacon);
                  emit BeaconUpgraded(newBeacon);
                  if (data.length > 0 || forceCall) {
                      Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
                  }
              }
          }
          
          /**
           * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
           * implementation address that can be changed. This address is stored in storage in the location specified by
           * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
           * implementation behind the proxy.
           */
          contract ERC1967Proxy is Proxy, ERC1967Upgrade {
              /**
               * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
               *
               * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
               * function call, and allows initializating the storage of the proxy like a Solidity constructor.
               */
              constructor(address _logic, bytes memory _data) payable {
                  assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                  _upgradeToAndCall(_logic, _data, false);
              }
          
              /**
               * @dev Returns the current implementation address.
               */
              function _implementation() internal view virtual override returns (address impl) {
                  return ERC1967Upgrade._getImplementation();
              }
          }
          
          /// @dev Zora NFT Creator Proxy Access Contract
          contract ERC721DropProxy is ERC1967Proxy {
              constructor(address _logic, bytes memory _data)
                  payable
                  ERC1967Proxy(_logic, _data)
              {}
          }

          File 3 of 5: Conduit
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { ConduitInterface } from "../interfaces/ConduitInterface.sol";
          import { ConduitItemType } from "./lib/ConduitEnums.sol";
          import { TokenTransferrer } from "../lib/TokenTransferrer.sol";
          // prettier-ignore
          import {
              ConduitTransfer,
              ConduitBatch1155Transfer
          } from "./lib/ConduitStructs.sol";
          import "./lib/ConduitConstants.sol";
          /**
           * @title Conduit
           * @author 0age
           * @notice This contract serves as an originator for "proxied" transfers. Each
           *         conduit is deployed and controlled by a "conduit controller" that can
           *         add and remove "channels" or contracts that can instruct the conduit
           *         to transfer approved ERC20/721/1155 tokens. *IMPORTANT NOTE: each
           *         conduit has an owner that can arbitrarily add or remove channels, and
           *         a malicious or negligent owner can add a channel that allows for any
           *         approved ERC20/721/1155 tokens to be taken immediately — be extremely
           *         cautious with what conduits you give token approvals to!*
           */
          contract Conduit is ConduitInterface, TokenTransferrer {
              // Set deployer as an immutable controller that can update channel statuses.
              address private immutable _controller;
              // Track the status of each channel.
              mapping(address => bool) private _channels;
              /**
               * @notice Ensure that the caller is currently registered as an open channel
               *         on the conduit.
               */
              modifier onlyOpenChannel() {
                  // Utilize assembly to access channel storage mapping directly.
                  assembly {
                      // Write the caller to scratch space.
                      mstore(ChannelKey_channel_ptr, caller())
                      // Write the storage slot for _channels to scratch space.
                      mstore(ChannelKey_slot_ptr, _channels.slot)
                      // Derive the position in storage of _channels[msg.sender]
                      // and check if the stored value is zero.
                      if iszero(
                          sload(keccak256(ChannelKey_channel_ptr, ChannelKey_length))
                      ) {
                          // The caller is not an open channel; revert with
                          // ChannelClosed(caller). First, set error signature in memory.
                          mstore(ChannelClosed_error_ptr, ChannelClosed_error_signature)
                          // Next, set the caller as the argument.
                          mstore(ChannelClosed_channel_ptr, caller())
                          // Finally, revert, returning full custom error with argument.
                          revert(ChannelClosed_error_ptr, ChannelClosed_error_length)
                      }
                  }
                  // Continue with function execution.
                  _;
              }
              /**
               * @notice In the constructor, set the deployer as the controller.
               */
              constructor() {
                  // Set the deployer as the controller.
                  _controller = msg.sender;
              }
              /**
               * @notice Execute a sequence of ERC20/721/1155 transfers. Only a caller
               *         with an open channel can call this function. Note that channels
               *         are expected to implement reentrancy protection if desired, and
               *         that cross-channel reentrancy may be possible if the conduit has
               *         multiple open channels at once. Also note that channels are
               *         expected to implement checks against transferring any zero-amount
               *         items if that constraint is desired.
               *
               * @param transfers The ERC20/721/1155 transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function execute(ConduitTransfer[] calldata transfers)
                  external
                  override
                  onlyOpenChannel
                  returns (bytes4 magicValue)
              {
                  // Retrieve the total number of transfers and place on the stack.
                  uint256 totalStandardTransfers = transfers.length;
                  // Iterate over each transfer.
                  for (uint256 i = 0; i < totalStandardTransfers; ) {
                      // Retrieve the transfer in question and perform the transfer.
                      _transfer(transfers[i]);
                      // Skip overflow check as for loop is indexed starting at zero.
                      unchecked {
                          ++i;
                      }
                  }
                  // Return a magic value indicating that the transfers were performed.
                  magicValue = this.execute.selector;
              }
              /**
               * @notice Execute a sequence of batch 1155 item transfers. Only a caller
               *         with an open channel can call this function. Note that channels
               *         are expected to implement reentrancy protection if desired, and
               *         that cross-channel reentrancy may be possible if the conduit has
               *         multiple open channels at once. Also note that channels are
               *         expected to implement checks against transferring any zero-amount
               *         items if that constraint is desired.
               *
               * @param batchTransfers The 1155 batch item transfers to perform.
               *
               * @return magicValue A magic value indicating that the item transfers were
               *                    performed successfully.
               */
              function executeBatch1155(
                  ConduitBatch1155Transfer[] calldata batchTransfers
              ) external override onlyOpenChannel returns (bytes4 magicValue) {
                  // Perform 1155 batch transfers. Note that memory should be considered
                  // entirely corrupted from this point forward.
                  _performERC1155BatchTransfers(batchTransfers);
                  // Return a magic value indicating that the transfers were performed.
                  magicValue = this.executeBatch1155.selector;
              }
              /**
               * @notice Execute a sequence of transfers, both single ERC20/721/1155 item
               *         transfers as well as batch 1155 item transfers. Only a caller
               *         with an open channel can call this function. Note that channels
               *         are expected to implement reentrancy protection if desired, and
               *         that cross-channel reentrancy may be possible if the conduit has
               *         multiple open channels at once. Also note that channels are
               *         expected to implement checks against transferring any zero-amount
               *         items if that constraint is desired.
               *
               * @param standardTransfers The ERC20/721/1155 item transfers to perform.
               * @param batchTransfers    The 1155 batch item transfers to perform.
               *
               * @return magicValue A magic value indicating that the item transfers were
               *                    performed successfully.
               */
              function executeWithBatch1155(
                  ConduitTransfer[] calldata standardTransfers,
                  ConduitBatch1155Transfer[] calldata batchTransfers
              ) external override onlyOpenChannel returns (bytes4 magicValue) {
                  // Retrieve the total number of transfers and place on the stack.
                  uint256 totalStandardTransfers = standardTransfers.length;
                  // Iterate over each standard transfer.
                  for (uint256 i = 0; i < totalStandardTransfers; ) {
                      // Retrieve the transfer in question and perform the transfer.
                      _transfer(standardTransfers[i]);
                      // Skip overflow check as for loop is indexed starting at zero.
                      unchecked {
                          ++i;
                      }
                  }
                  // Perform 1155 batch transfers. Note that memory should be considered
                  // entirely corrupted from this point forward aside from the free memory
                  // pointer having the default value.
                  _performERC1155BatchTransfers(batchTransfers);
                  // Return a magic value indicating that the transfers were performed.
                  magicValue = this.executeWithBatch1155.selector;
              }
              /**
               * @notice Open or close a given channel. Only callable by the controller.
               *
               * @param channel The channel to open or close.
               * @param isOpen  The status of the channel (either open or closed).
               */
              function updateChannel(address channel, bool isOpen) external override {
                  // Ensure that the caller is the controller of this contract.
                  if (msg.sender != _controller) {
                      revert InvalidController();
                  }
                  // Ensure that the channel does not already have the indicated status.
                  if (_channels[channel] == isOpen) {
                      revert ChannelStatusAlreadySet(channel, isOpen);
                  }
                  // Update the status of the channel.
                  _channels[channel] = isOpen;
                  // Emit a corresponding event.
                  emit ChannelUpdated(channel, isOpen);
              }
              /**
               * @dev Internal function to transfer a given ERC20/721/1155 item. Note that
               *      channels are expected to implement checks against transferring any
               *      zero-amount items if that constraint is desired.
               *
               * @param item The ERC20/721/1155 item to transfer.
               */
              function _transfer(ConduitTransfer calldata item) internal {
                  // Determine the transfer method based on the respective item type.
                  if (item.itemType == ConduitItemType.ERC20) {
                      // Transfer ERC20 token. Note that item.identifier is ignored and
                      // therefore ERC20 transfer items are potentially malleable — this
                      // check should be performed by the calling channel if a constraint
                      // on item malleability is desired.
                      _performERC20Transfer(item.token, item.from, item.to, item.amount);
                  } else if (item.itemType == ConduitItemType.ERC721) {
                      // Ensure that exactly one 721 item is being transferred.
                      if (item.amount != 1) {
                          revert InvalidERC721TransferAmount();
                      }
                      // Transfer ERC721 token.
                      _performERC721Transfer(
                          item.token,
                          item.from,
                          item.to,
                          item.identifier
                      );
                  } else if (item.itemType == ConduitItemType.ERC1155) {
                      // Transfer ERC1155 token.
                      _performERC1155Transfer(
                          item.token,
                          item.from,
                          item.to,
                          item.identifier,
                          item.amount
                      );
                  } else {
                      // Throw with an error.
                      revert InvalidItemType();
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // prettier-ignore
          import {
              ConduitTransfer,
              ConduitBatch1155Transfer
          } from "../conduit/lib/ConduitStructs.sol";
          /**
           * @title ConduitInterface
           * @author 0age
           * @notice ConduitInterface contains all external function interfaces, events,
           *         and errors for conduit contracts.
           */
          interface ConduitInterface {
              /**
               * @dev Revert with an error when attempting to execute transfers using a
               *      caller that does not have an open channel.
               */
              error ChannelClosed(address channel);
              /**
               * @dev Revert with an error when attempting to update a channel to the
               *      current status of that channel.
               */
              error ChannelStatusAlreadySet(address channel, bool isOpen);
              /**
               * @dev Revert with an error when attempting to execute a transfer for an
               *      item that does not have an ERC20/721/1155 item type.
               */
              error InvalidItemType();
              /**
               * @dev Revert with an error when attempting to update the status of a
               *      channel from a caller that is not the conduit controller.
               */
              error InvalidController();
              /**
               * @dev Emit an event whenever a channel is opened or closed.
               *
               * @param channel The channel that has been updated.
               * @param open    A boolean indicating whether the conduit is open or not.
               */
              event ChannelUpdated(address indexed channel, bool open);
              /**
               * @notice Execute a sequence of ERC20/721/1155 transfers. Only a caller
               *         with an open channel can call this function.
               *
               * @param transfers The ERC20/721/1155 transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function execute(ConduitTransfer[] calldata transfers)
                  external
                  returns (bytes4 magicValue);
              /**
               * @notice Execute a sequence of batch 1155 transfers. Only a caller with an
               *         open channel can call this function.
               *
               * @param batch1155Transfers The 1155 batch transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function executeBatch1155(
                  ConduitBatch1155Transfer[] calldata batch1155Transfers
              ) external returns (bytes4 magicValue);
              /**
               * @notice Execute a sequence of transfers, both single and batch 1155. Only
               *         a caller with an open channel can call this function.
               *
               * @param standardTransfers  The ERC20/721/1155 transfers to perform.
               * @param batch1155Transfers The 1155 batch transfers to perform.
               *
               * @return magicValue A magic value indicating that the transfers were
               *                    performed successfully.
               */
              function executeWithBatch1155(
                  ConduitTransfer[] calldata standardTransfers,
                  ConduitBatch1155Transfer[] calldata batch1155Transfers
              ) external returns (bytes4 magicValue);
              /**
               * @notice Open or close a given channel. Only callable by the controller.
               *
               * @param channel The channel to open or close.
               * @param isOpen  The status of the channel (either open or closed).
               */
              function updateChannel(address channel, bool isOpen) external;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          enum ConduitItemType {
              NATIVE, // unused
              ERC20,
              ERC721,
              ERC1155
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import "./TokenTransferrerConstants.sol";
          // prettier-ignore
          import {
              TokenTransferrerErrors
          } from "../interfaces/TokenTransferrerErrors.sol";
          import { ConduitBatch1155Transfer } from "../conduit/lib/ConduitStructs.sol";
          /**
           * @title TokenTransferrer
           * @author 0age
           * @custom:coauthor d1ll0n
           * @custom:coauthor transmissions11
           * @notice TokenTransferrer is a library for performing optimized ERC20, ERC721,
           *         ERC1155, and batch ERC1155 transfers, used by both Seaport as well as
           *         by conduits deployed by the ConduitController. Use great caution when
           *         considering these functions for use in other codebases, as there are
           *         significant side effects and edge cases that need to be thoroughly
           *         understood and carefully addressed.
           */
          contract TokenTransferrer is TokenTransferrerErrors {
              /**
               * @dev Internal function to transfer ERC20 tokens from a given originator
               *      to a given recipient. Sufficient approvals must be set on the
               *      contract performing the transfer.
               *
               * @param token      The ERC20 token to transfer.
               * @param from       The originator of the transfer.
               * @param to         The recipient of the transfer.
               * @param amount     The amount to transfer.
               */
              function _performERC20Transfer(
                  address token,
                  address from,
                  address to,
                  uint256 amount
              ) internal {
                  // Utilize assembly to perform an optimized ERC20 token transfer.
                  assembly {
                      // The free memory pointer memory slot will be used when populating
                      // call data for the transfer; read the value and restore it later.
                      let memPointer := mload(FreeMemoryPointerSlot)
                      // Write call data into memory, starting with function selector.
                      mstore(ERC20_transferFrom_sig_ptr, ERC20_transferFrom_signature)
                      mstore(ERC20_transferFrom_from_ptr, from)
                      mstore(ERC20_transferFrom_to_ptr, to)
                      mstore(ERC20_transferFrom_amount_ptr, amount)
                      // Make call & copy up to 32 bytes of return data to scratch space.
                      // Scratch space does not need to be cleared ahead of time, as the
                      // subsequent check will ensure that either at least a full word of
                      // return data is received (in which case it will be overwritten) or
                      // that no data is received (in which case scratch space will be
                      // ignored) on a successful call to the given token.
                      let callStatus := call(
                          gas(),
                          token,
                          0,
                          ERC20_transferFrom_sig_ptr,
                          ERC20_transferFrom_length,
                          0,
                          OneWord
                      )
                      // Determine whether transfer was successful using status & result.
                      let success := and(
                          // Set success to whether the call reverted, if not check it
                          // either returned exactly 1 (can't just be non-zero data), or
                          // had no return data.
                          or(
                              and(eq(mload(0), 1), gt(returndatasize(), 31)),
                              iszero(returndatasize())
                          ),
                          callStatus
                      )
                      // Handle cases where either the transfer failed or no data was
                      // returned. Group these, as most transfers will succeed with data.
                      // Equivalent to `or(iszero(success), iszero(returndatasize()))`
                      // but after it's inverted for JUMPI this expression is cheaper.
                      if iszero(and(success, iszero(iszero(returndatasize())))) {
                          // If the token has no code or the transfer failed: Equivalent
                          // to `or(iszero(success), iszero(extcodesize(token)))` but
                          // after it's inverted for JUMPI this expression is cheaper.
                          if iszero(and(iszero(iszero(extcodesize(token))), success)) {
                              // If the transfer failed:
                              if iszero(success) {
                                  // If it was due to a revert:
                                  if iszero(callStatus) {
                                      // If it returned a message, bubble it up as long as
                                      // sufficient gas remains to do so:
                                      if returndatasize() {
                                          // Ensure that sufficient gas is available to
                                          // copy returndata while expanding memory where
                                          // necessary. Start by computing the word size
                                          // of returndata and allocated memory. Round up
                                          // to the nearest full word.
                                          let returnDataWords := div(
                                              add(returndatasize(), AlmostOneWord),
                                              OneWord
                                          )
                                          // Note: use the free memory pointer in place of
                                          // msize() to work around a Yul warning that
                                          // prevents accessing msize directly when the IR
                                          // pipeline is activated.
                                          let msizeWords := div(memPointer, OneWord)
                                          // Next, compute the cost of the returndatacopy.
                                          let cost := mul(CostPerWord, returnDataWords)
                                          // Then, compute cost of new memory allocation.
                                          if gt(returnDataWords, msizeWords) {
                                              cost := add(
                                                  cost,
                                                  add(
                                                      mul(
                                                          sub(
                                                              returnDataWords,
                                                              msizeWords
                                                          ),
                                                          CostPerWord
                                                      ),
                                                      div(
                                                          sub(
                                                              mul(
                                                                  returnDataWords,
                                                                  returnDataWords
                                                              ),
                                                              mul(msizeWords, msizeWords)
                                                          ),
                                                          MemoryExpansionCoefficient
                                                      )
                                                  )
                                              )
                                          }
                                          // Finally, add a small constant and compare to
                                          // gas remaining; bubble up the revert data if
                                          // enough gas is still available.
                                          if lt(add(cost, ExtraGasBuffer), gas()) {
                                              // Copy returndata to memory; overwrite
                                              // existing memory.
                                              returndatacopy(0, 0, returndatasize())
                                              // Revert, specifying memory region with
                                              // copied returndata.
                                              revert(0, returndatasize())
                                          }
                                      }
                                      // Otherwise revert with a generic error message.
                                      mstore(
                                          TokenTransferGenericFailure_error_sig_ptr,
                                          TokenTransferGenericFailure_error_signature
                                      )
                                      mstore(
                                          TokenTransferGenericFailure_error_token_ptr,
                                          token
                                      )
                                      mstore(
                                          TokenTransferGenericFailure_error_from_ptr,
                                          from
                                      )
                                      mstore(TokenTransferGenericFailure_error_to_ptr, to)
                                      mstore(TokenTransferGenericFailure_error_id_ptr, 0)
                                      mstore(
                                          TokenTransferGenericFailure_error_amount_ptr,
                                          amount
                                      )
                                      revert(
                                          TokenTransferGenericFailure_error_sig_ptr,
                                          TokenTransferGenericFailure_error_length
                                      )
                                  }
                                  // Otherwise revert with a message about the token
                                  // returning false or non-compliant return values.
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_sig_ptr,
                                      BadReturnValueFromERC20OnTransfer_error_signature
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_token_ptr,
                                      token
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_from_ptr,
                                      from
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_to_ptr,
                                      to
                                  )
                                  mstore(
                                      BadReturnValueFromERC20OnTransfer_error_amount_ptr,
                                      amount
                                  )
                                  revert(
                                      BadReturnValueFromERC20OnTransfer_error_sig_ptr,
                                      BadReturnValueFromERC20OnTransfer_error_length
                                  )
                              }
                              // Otherwise, revert with error about token not having code:
                              mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                              mstore(NoContract_error_token_ptr, token)
                              revert(NoContract_error_sig_ptr, NoContract_error_length)
                          }
                          // Otherwise, the token just returned no data despite the call
                          // having succeeded; no need to optimize for this as it's not
                          // technically ERC20 compliant.
                      }
                      // Restore the original free memory pointer.
                      mstore(FreeMemoryPointerSlot, memPointer)
                      // Restore the zero slot to zero.
                      mstore(ZeroSlot, 0)
                  }
              }
              /**
               * @dev Internal function to transfer an ERC721 token from a given
               *      originator to a given recipient. Sufficient approvals must be set on
               *      the contract performing the transfer. Note that this function does
               *      not check whether the receiver can accept the ERC721 token (i.e. it
               *      does not use `safeTransferFrom`).
               *
               * @param token      The ERC721 token to transfer.
               * @param from       The originator of the transfer.
               * @param to         The recipient of the transfer.
               * @param identifier The tokenId to transfer.
               */
              function _performERC721Transfer(
                  address token,
                  address from,
                  address to,
                  uint256 identifier
              ) internal {
                  // Utilize assembly to perform an optimized ERC721 token transfer.
                  assembly {
                      // If the token has no code, revert.
                      if iszero(extcodesize(token)) {
                          mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                          mstore(NoContract_error_token_ptr, token)
                          revert(NoContract_error_sig_ptr, NoContract_error_length)
                      }
                      // The free memory pointer memory slot will be used when populating
                      // call data for the transfer; read the value and restore it later.
                      let memPointer := mload(FreeMemoryPointerSlot)
                      // Write call data to memory starting with function selector.
                      mstore(ERC721_transferFrom_sig_ptr, ERC721_transferFrom_signature)
                      mstore(ERC721_transferFrom_from_ptr, from)
                      mstore(ERC721_transferFrom_to_ptr, to)
                      mstore(ERC721_transferFrom_id_ptr, identifier)
                      // Perform the call, ignoring return data.
                      let success := call(
                          gas(),
                          token,
                          0,
                          ERC721_transferFrom_sig_ptr,
                          ERC721_transferFrom_length,
                          0,
                          0
                      )
                      // If the transfer reverted:
                      if iszero(success) {
                          // If it returned a message, bubble it up as long as sufficient
                          // gas remains to do so:
                          if returndatasize() {
                              // Ensure that sufficient gas is available to copy
                              // returndata while expanding memory where necessary. Start
                              // by computing word size of returndata & allocated memory.
                              // Round up to the nearest full word.
                              let returnDataWords := div(
                                  add(returndatasize(), AlmostOneWord),
                                  OneWord
                              )
                              // Note: use the free memory pointer in place of msize() to
                              // work around a Yul warning that prevents accessing msize
                              // directly when the IR pipeline is activated.
                              let msizeWords := div(memPointer, OneWord)
                              // Next, compute the cost of the returndatacopy.
                              let cost := mul(CostPerWord, returnDataWords)
                              // Then, compute cost of new memory allocation.
                              if gt(returnDataWords, msizeWords) {
                                  cost := add(
                                      cost,
                                      add(
                                          mul(
                                              sub(returnDataWords, msizeWords),
                                              CostPerWord
                                          ),
                                          div(
                                              sub(
                                                  mul(returnDataWords, returnDataWords),
                                                  mul(msizeWords, msizeWords)
                                              ),
                                              MemoryExpansionCoefficient
                                          )
                                      )
                                  )
                              }
                              // Finally, add a small constant and compare to gas
                              // remaining; bubble up the revert data if enough gas is
                              // still available.
                              if lt(add(cost, ExtraGasBuffer), gas()) {
                                  // Copy returndata to memory; overwrite existing memory.
                                  returndatacopy(0, 0, returndatasize())
                                  // Revert, giving memory region with copied returndata.
                                  revert(0, returndatasize())
                              }
                          }
                          // Otherwise revert with a generic error message.
                          mstore(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_signature
                          )
                          mstore(TokenTransferGenericFailure_error_token_ptr, token)
                          mstore(TokenTransferGenericFailure_error_from_ptr, from)
                          mstore(TokenTransferGenericFailure_error_to_ptr, to)
                          mstore(TokenTransferGenericFailure_error_id_ptr, identifier)
                          mstore(TokenTransferGenericFailure_error_amount_ptr, 1)
                          revert(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_length
                          )
                      }
                      // Restore the original free memory pointer.
                      mstore(FreeMemoryPointerSlot, memPointer)
                      // Restore the zero slot to zero.
                      mstore(ZeroSlot, 0)
                  }
              }
              /**
               * @dev Internal function to transfer ERC1155 tokens from a given
               *      originator to a given recipient. Sufficient approvals must be set on
               *      the contract performing the transfer and contract recipients must
               *      implement the ERC1155TokenReceiver interface to indicate that they
               *      are willing to accept the transfer.
               *
               * @param token      The ERC1155 token to transfer.
               * @param from       The originator of the transfer.
               * @param to         The recipient of the transfer.
               * @param identifier The id to transfer.
               * @param amount     The amount to transfer.
               */
              function _performERC1155Transfer(
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount
              ) internal {
                  // Utilize assembly to perform an optimized ERC1155 token transfer.
                  assembly {
                      // If the token has no code, revert.
                      if iszero(extcodesize(token)) {
                          mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                          mstore(NoContract_error_token_ptr, token)
                          revert(NoContract_error_sig_ptr, NoContract_error_length)
                      }
                      // The following memory slots will be used when populating call data
                      // for the transfer; read the values and restore them later.
                      let memPointer := mload(FreeMemoryPointerSlot)
                      let slot0x80 := mload(Slot0x80)
                      let slot0xA0 := mload(Slot0xA0)
                      let slot0xC0 := mload(Slot0xC0)
                      // Write call data into memory, beginning with function selector.
                      mstore(
                          ERC1155_safeTransferFrom_sig_ptr,
                          ERC1155_safeTransferFrom_signature
                      )
                      mstore(ERC1155_safeTransferFrom_from_ptr, from)
                      mstore(ERC1155_safeTransferFrom_to_ptr, to)
                      mstore(ERC1155_safeTransferFrom_id_ptr, identifier)
                      mstore(ERC1155_safeTransferFrom_amount_ptr, amount)
                      mstore(
                          ERC1155_safeTransferFrom_data_offset_ptr,
                          ERC1155_safeTransferFrom_data_length_offset
                      )
                      mstore(ERC1155_safeTransferFrom_data_length_ptr, 0)
                      // Perform the call, ignoring return data.
                      let success := call(
                          gas(),
                          token,
                          0,
                          ERC1155_safeTransferFrom_sig_ptr,
                          ERC1155_safeTransferFrom_length,
                          0,
                          0
                      )
                      // If the transfer reverted:
                      if iszero(success) {
                          // If it returned a message, bubble it up as long as sufficient
                          // gas remains to do so:
                          if returndatasize() {
                              // Ensure that sufficient gas is available to copy
                              // returndata while expanding memory where necessary. Start
                              // by computing word size of returndata & allocated memory.
                              // Round up to the nearest full word.
                              let returnDataWords := div(
                                  add(returndatasize(), AlmostOneWord),
                                  OneWord
                              )
                              // Note: use the free memory pointer in place of msize() to
                              // work around a Yul warning that prevents accessing msize
                              // directly when the IR pipeline is activated.
                              let msizeWords := div(memPointer, OneWord)
                              // Next, compute the cost of the returndatacopy.
                              let cost := mul(CostPerWord, returnDataWords)
                              // Then, compute cost of new memory allocation.
                              if gt(returnDataWords, msizeWords) {
                                  cost := add(
                                      cost,
                                      add(
                                          mul(
                                              sub(returnDataWords, msizeWords),
                                              CostPerWord
                                          ),
                                          div(
                                              sub(
                                                  mul(returnDataWords, returnDataWords),
                                                  mul(msizeWords, msizeWords)
                                              ),
                                              MemoryExpansionCoefficient
                                          )
                                      )
                                  )
                              }
                              // Finally, add a small constant and compare to gas
                              // remaining; bubble up the revert data if enough gas is
                              // still available.
                              if lt(add(cost, ExtraGasBuffer), gas()) {
                                  // Copy returndata to memory; overwrite existing memory.
                                  returndatacopy(0, 0, returndatasize())
                                  // Revert, giving memory region with copied returndata.
                                  revert(0, returndatasize())
                              }
                          }
                          // Otherwise revert with a generic error message.
                          mstore(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_signature
                          )
                          mstore(TokenTransferGenericFailure_error_token_ptr, token)
                          mstore(TokenTransferGenericFailure_error_from_ptr, from)
                          mstore(TokenTransferGenericFailure_error_to_ptr, to)
                          mstore(TokenTransferGenericFailure_error_id_ptr, identifier)
                          mstore(TokenTransferGenericFailure_error_amount_ptr, amount)
                          revert(
                              TokenTransferGenericFailure_error_sig_ptr,
                              TokenTransferGenericFailure_error_length
                          )
                      }
                      mstore(Slot0x80, slot0x80) // Restore slot 0x80.
                      mstore(Slot0xA0, slot0xA0) // Restore slot 0xA0.
                      mstore(Slot0xC0, slot0xC0) // Restore slot 0xC0.
                      // Restore the original free memory pointer.
                      mstore(FreeMemoryPointerSlot, memPointer)
                      // Restore the zero slot to zero.
                      mstore(ZeroSlot, 0)
                  }
              }
              /**
               * @dev Internal function to transfer ERC1155 tokens from a given
               *      originator to a given recipient. Sufficient approvals must be set on
               *      the contract performing the transfer and contract recipients must
               *      implement the ERC1155TokenReceiver interface to indicate that they
               *      are willing to accept the transfer. NOTE: this function is not
               *      memory-safe; it will overwrite existing memory, restore the free
               *      memory pointer to the default value, and overwrite the zero slot.
               *      This function should only be called once memory is no longer
               *      required and when uninitialized arrays are not utilized, and memory
               *      should be considered fully corrupted (aside from the existence of a
               *      default-value free memory pointer) after calling this function.
               *
               * @param batchTransfers The group of 1155 batch transfers to perform.
               */
              function _performERC1155BatchTransfers(
                  ConduitBatch1155Transfer[] calldata batchTransfers
              ) internal {
                  // Utilize assembly to perform optimized batch 1155 transfers.
                  assembly {
                      let len := batchTransfers.length
                      // Pointer to first head in the array, which is offset to the struct
                      // at each index. This gets incremented after each loop to avoid
                      // multiplying by 32 to get the offset for each element.
                      let nextElementHeadPtr := batchTransfers.offset
                      // Pointer to beginning of the head of the array. This is the
                      // reference position each offset references. It's held static to
                      // let each loop calculate the data position for an element.
                      let arrayHeadPtr := nextElementHeadPtr
                      // Write the function selector, which will be reused for each call:
                      // safeBatchTransferFrom(address,address,uint256[],uint256[],bytes)
                      mstore(
                          ConduitBatch1155Transfer_from_offset,
                          ERC1155_safeBatchTransferFrom_signature
                      )
                      // Iterate over each batch transfer.
                      for {
                          let i := 0
                      } lt(i, len) {
                          i := add(i, 1)
                      } {
                          // Read the offset to the beginning of the element and add
                          // it to pointer to the beginning of the array head to get
                          // the absolute position of the element in calldata.
                          let elementPtr := add(
                              arrayHeadPtr,
                              calldataload(nextElementHeadPtr)
                          )
                          // Retrieve the token from calldata.
                          let token := calldataload(elementPtr)
                          // If the token has no code, revert.
                          if iszero(extcodesize(token)) {
                              mstore(NoContract_error_sig_ptr, NoContract_error_signature)
                              mstore(NoContract_error_token_ptr, token)
                              revert(NoContract_error_sig_ptr, NoContract_error_length)
                          }
                          // Get the total number of supplied ids.
                          let idsLength := calldataload(
                              add(elementPtr, ConduitBatch1155Transfer_ids_length_offset)
                          )
                          // Determine the expected offset for the amounts array.
                          let expectedAmountsOffset := add(
                              ConduitBatch1155Transfer_amounts_length_baseOffset,
                              mul(idsLength, OneWord)
                          )
                          // Validate struct encoding.
                          let invalidEncoding := iszero(
                              and(
                                  // ids.length == amounts.length
                                  eq(
                                      idsLength,
                                      calldataload(add(elementPtr, expectedAmountsOffset))
                                  ),
                                  and(
                                      // ids_offset == 0xa0
                                      eq(
                                          calldataload(
                                              add(
                                                  elementPtr,
                                                  ConduitBatch1155Transfer_ids_head_offset
                                              )
                                          ),
                                          ConduitBatch1155Transfer_ids_length_offset
                                      ),
                                      // amounts_offset == 0xc0 + ids.length*32
                                      eq(
                                          calldataload(
                                              add(
                                                  elementPtr,
                                                  ConduitBatchTransfer_amounts_head_offset
                                              )
                                          ),
                                          expectedAmountsOffset
                                      )
                                  )
                              )
                          )
                          // Revert with an error if the encoding is not valid.
                          if invalidEncoding {
                              mstore(
                                  Invalid1155BatchTransferEncoding_ptr,
                                  Invalid1155BatchTransferEncoding_selector
                              )
                              revert(
                                  Invalid1155BatchTransferEncoding_ptr,
                                  Invalid1155BatchTransferEncoding_length
                              )
                          }
                          // Update the offset position for the next loop
                          nextElementHeadPtr := add(nextElementHeadPtr, OneWord)
                          // Copy the first section of calldata (before dynamic values).
                          calldatacopy(
                              BatchTransfer1155Params_ptr,
                              add(elementPtr, ConduitBatch1155Transfer_from_offset),
                              ConduitBatch1155Transfer_usable_head_size
                          )
                          // Determine size of calldata required for ids and amounts. Note
                          // that the size includes both lengths as well as the data.
                          let idsAndAmountsSize := add(TwoWords, mul(idsLength, TwoWords))
                          // Update the offset for the data array in memory.
                          mstore(
                              BatchTransfer1155Params_data_head_ptr,
                              add(
                                  BatchTransfer1155Params_ids_length_offset,
                                  idsAndAmountsSize
                              )
                          )
                          // Set the length of the data array in memory to zero.
                          mstore(
                              add(
                                  BatchTransfer1155Params_data_length_basePtr,
                                  idsAndAmountsSize
                              ),
                              0
                          )
                          // Determine the total calldata size for the call to transfer.
                          let transferDataSize := add(
                              BatchTransfer1155Params_calldata_baseSize,
                              idsAndAmountsSize
                          )
                          // Copy second section of calldata (including dynamic values).
                          calldatacopy(
                              BatchTransfer1155Params_ids_length_ptr,
                              add(elementPtr, ConduitBatch1155Transfer_ids_length_offset),
                              idsAndAmountsSize
                          )
                          // Perform the call to transfer 1155 tokens.
                          let success := call(
                              gas(),
                              token,
                              0,
                              ConduitBatch1155Transfer_from_offset, // Data portion start.
                              transferDataSize, // Location of the length of callData.
                              0,
                              0
                          )
                          // If the transfer reverted:
                          if iszero(success) {
                              // If it returned a message, bubble it up as long as
                              // sufficient gas remains to do so:
                              if returndatasize() {
                                  // Ensure that sufficient gas is available to copy
                                  // returndata while expanding memory where necessary.
                                  // Start by computing word size of returndata and
                                  // allocated memory. Round up to the nearest full word.
                                  let returnDataWords := div(
                                      add(returndatasize(), AlmostOneWord),
                                      OneWord
                                  )
                                  // Note: use transferDataSize in place of msize() to
                                  // work around a Yul warning that prevents accessing
                                  // msize directly when the IR pipeline is activated.
                                  // The free memory pointer is not used here because
                                  // this function does almost all memory management
                                  // manually and does not update it, and transferDataSize
                                  // should be the largest memory value used (unless a
                                  // previous batch was larger).
                                  let msizeWords := div(transferDataSize, OneWord)
                                  // Next, compute the cost of the returndatacopy.
                                  let cost := mul(CostPerWord, returnDataWords)
                                  // Then, compute cost of new memory allocation.
                                  if gt(returnDataWords, msizeWords) {
                                      cost := add(
                                          cost,
                                          add(
                                              mul(
                                                  sub(returnDataWords, msizeWords),
                                                  CostPerWord
                                              ),
                                              div(
                                                  sub(
                                                      mul(
                                                          returnDataWords,
                                                          returnDataWords
                                                      ),
                                                      mul(msizeWords, msizeWords)
                                                  ),
                                                  MemoryExpansionCoefficient
                                              )
                                          )
                                      )
                                  }
                                  // Finally, add a small constant and compare to gas
                                  // remaining; bubble up the revert data if enough gas is
                                  // still available.
                                  if lt(add(cost, ExtraGasBuffer), gas()) {
                                      // Copy returndata to memory; overwrite existing.
                                      returndatacopy(0, 0, returndatasize())
                                      // Revert with memory region containing returndata.
                                      revert(0, returndatasize())
                                  }
                              }
                              // Set the error signature.
                              mstore(
                                  0,
                                  ERC1155BatchTransferGenericFailure_error_signature
                              )
                              // Write the token.
                              mstore(ERC1155BatchTransferGenericFailure_token_ptr, token)
                              // Increase the offset to ids by 32.
                              mstore(
                                  BatchTransfer1155Params_ids_head_ptr,
                                  ERC1155BatchTransferGenericFailure_ids_offset
                              )
                              // Increase the offset to amounts by 32.
                              mstore(
                                  BatchTransfer1155Params_amounts_head_ptr,
                                  add(
                                      OneWord,
                                      mload(BatchTransfer1155Params_amounts_head_ptr)
                                  )
                              )
                              // Return modified region. The total size stays the same as
                              // `token` uses the same number of bytes as `data.length`.
                              revert(0, transferDataSize)
                          }
                      }
                      // Reset the free memory pointer to the default value; memory must
                      // be assumed to be dirtied and not reused from this point forward.
                      // Also note that the zero slot is not reset to zero, meaning empty
                      // arrays cannot be safely created or utilized until it is restored.
                      mstore(FreeMemoryPointerSlot, DefaultFreeMemoryPointer)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          import { ConduitItemType } from "./ConduitEnums.sol";
          struct ConduitTransfer {
              ConduitItemType itemType;
              address token;
              address from;
              address to;
              uint256 identifier;
              uint256 amount;
          }
          struct ConduitBatch1155Transfer {
              address token;
              address from;
              address to;
              uint256[] ids;
              uint256[] amounts;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          // error ChannelClosed(address channel)
          uint256 constant ChannelClosed_error_signature = (
              0x93daadf200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ChannelClosed_error_ptr = 0x00;
          uint256 constant ChannelClosed_channel_ptr = 0x4;
          uint256 constant ChannelClosed_error_length = 0x24;
          // For the mapping:
          // mapping(address => bool) channels
          // The position in storage for a particular account is:
          // keccak256(abi.encode(account, channels.slot))
          uint256 constant ChannelKey_channel_ptr = 0x00;
          uint256 constant ChannelKey_slot_ptr = 0x20;
          uint256 constant ChannelKey_length = 0x40;
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /*
           * -------------------------- Disambiguation & Other Notes ---------------------
           *    - The term "head" is used as it is in the documentation for ABI encoding,
           *      but only in reference to dynamic types, i.e. it always refers to the
           *      offset or pointer to the body of a dynamic type. In calldata, the head
           *      is always an offset (relative to the parent object), while in memory,
           *      the head is always the pointer to the body. More information found here:
           *      https://docs.soliditylang.org/en/v0.8.14/abi-spec.html#argument-encoding
           *        - Note that the length of an array is separate from and precedes the
           *          head of the array.
           *
           *    - The term "body" is used in place of the term "head" used in the ABI
           *      documentation. It refers to the start of the data for a dynamic type,
           *      e.g. the first word of a struct or the first word of the first element
           *      in an array.
           *
           *    - The term "pointer" is used to describe the absolute position of a value
           *      and never an offset relative to another value.
           *        - The suffix "_ptr" refers to a memory pointer.
           *        - The suffix "_cdPtr" refers to a calldata pointer.
           *
           *    - The term "offset" is used to describe the position of a value relative
           *      to some parent value. For example, OrderParameters_conduit_offset is the
           *      offset to the "conduit" value in the OrderParameters struct relative to
           *      the start of the body.
           *        - Note: Offsets are used to derive pointers.
           *
           *    - Some structs have pointers defined for all of their fields in this file.
           *      Lines which are commented out are fields that are not used in the
           *      codebase but have been left in for readability.
           */
          uint256 constant AlmostOneWord = 0x1f;
          uint256 constant OneWord = 0x20;
          uint256 constant TwoWords = 0x40;
          uint256 constant ThreeWords = 0x60;
          uint256 constant FreeMemoryPointerSlot = 0x40;
          uint256 constant ZeroSlot = 0x60;
          uint256 constant DefaultFreeMemoryPointer = 0x80;
          uint256 constant Slot0x80 = 0x80;
          uint256 constant Slot0xA0 = 0xa0;
          uint256 constant Slot0xC0 = 0xc0;
          // abi.encodeWithSignature("transferFrom(address,address,uint256)")
          uint256 constant ERC20_transferFrom_signature = (
              0x23b872dd00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC20_transferFrom_sig_ptr = 0x0;
          uint256 constant ERC20_transferFrom_from_ptr = 0x04;
          uint256 constant ERC20_transferFrom_to_ptr = 0x24;
          uint256 constant ERC20_transferFrom_amount_ptr = 0x44;
          uint256 constant ERC20_transferFrom_length = 0x64; // 4 + 32 * 3 == 100
          // abi.encodeWithSignature(
          //     "safeTransferFrom(address,address,uint256,uint256,bytes)"
          // )
          uint256 constant ERC1155_safeTransferFrom_signature = (
              0xf242432a00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC1155_safeTransferFrom_sig_ptr = 0x0;
          uint256 constant ERC1155_safeTransferFrom_from_ptr = 0x04;
          uint256 constant ERC1155_safeTransferFrom_to_ptr = 0x24;
          uint256 constant ERC1155_safeTransferFrom_id_ptr = 0x44;
          uint256 constant ERC1155_safeTransferFrom_amount_ptr = 0x64;
          uint256 constant ERC1155_safeTransferFrom_data_offset_ptr = 0x84;
          uint256 constant ERC1155_safeTransferFrom_data_length_ptr = 0xa4;
          uint256 constant ERC1155_safeTransferFrom_length = 0xc4; // 4 + 32 * 6 == 196
          uint256 constant ERC1155_safeTransferFrom_data_length_offset = 0xa0;
          // abi.encodeWithSignature(
          //     "safeBatchTransferFrom(address,address,uint256[],uint256[],bytes)"
          // )
          uint256 constant ERC1155_safeBatchTransferFrom_signature = (
              0x2eb2c2d600000000000000000000000000000000000000000000000000000000
          );
          bytes4 constant ERC1155_safeBatchTransferFrom_selector = bytes4(
              bytes32(ERC1155_safeBatchTransferFrom_signature)
          );
          uint256 constant ERC721_transferFrom_signature = ERC20_transferFrom_signature;
          uint256 constant ERC721_transferFrom_sig_ptr = 0x0;
          uint256 constant ERC721_transferFrom_from_ptr = 0x04;
          uint256 constant ERC721_transferFrom_to_ptr = 0x24;
          uint256 constant ERC721_transferFrom_id_ptr = 0x44;
          uint256 constant ERC721_transferFrom_length = 0x64; // 4 + 32 * 3 == 100
          // abi.encodeWithSignature("NoContract(address)")
          uint256 constant NoContract_error_signature = (
              0x5f15d67200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant NoContract_error_sig_ptr = 0x0;
          uint256 constant NoContract_error_token_ptr = 0x4;
          uint256 constant NoContract_error_length = 0x24; // 4 + 32 == 36
          // abi.encodeWithSignature(
          //     "TokenTransferGenericFailure(address,address,address,uint256,uint256)"
          // )
          uint256 constant TokenTransferGenericFailure_error_signature = (
              0xf486bc8700000000000000000000000000000000000000000000000000000000
          );
          uint256 constant TokenTransferGenericFailure_error_sig_ptr = 0x0;
          uint256 constant TokenTransferGenericFailure_error_token_ptr = 0x4;
          uint256 constant TokenTransferGenericFailure_error_from_ptr = 0x24;
          uint256 constant TokenTransferGenericFailure_error_to_ptr = 0x44;
          uint256 constant TokenTransferGenericFailure_error_id_ptr = 0x64;
          uint256 constant TokenTransferGenericFailure_error_amount_ptr = 0x84;
          // 4 + 32 * 5 == 164
          uint256 constant TokenTransferGenericFailure_error_length = 0xa4;
          // abi.encodeWithSignature(
          //     "BadReturnValueFromERC20OnTransfer(address,address,address,uint256)"
          // )
          uint256 constant BadReturnValueFromERC20OnTransfer_error_signature = (
              0x9889192300000000000000000000000000000000000000000000000000000000
          );
          uint256 constant BadReturnValueFromERC20OnTransfer_error_sig_ptr = 0x0;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_token_ptr = 0x4;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_from_ptr = 0x24;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_to_ptr = 0x44;
          uint256 constant BadReturnValueFromERC20OnTransfer_error_amount_ptr = 0x64;
          // 4 + 32 * 4 == 132
          uint256 constant BadReturnValueFromERC20OnTransfer_error_length = 0x84;
          uint256 constant ExtraGasBuffer = 0x20;
          uint256 constant CostPerWord = 3;
          uint256 constant MemoryExpansionCoefficient = 0x200;
          // Values are offset by 32 bytes in order to write the token to the beginning
          // in the event of a revert
          uint256 constant BatchTransfer1155Params_ptr = 0x24;
          uint256 constant BatchTransfer1155Params_ids_head_ptr = 0x64;
          uint256 constant BatchTransfer1155Params_amounts_head_ptr = 0x84;
          uint256 constant BatchTransfer1155Params_data_head_ptr = 0xa4;
          uint256 constant BatchTransfer1155Params_data_length_basePtr = 0xc4;
          uint256 constant BatchTransfer1155Params_calldata_baseSize = 0xc4;
          uint256 constant BatchTransfer1155Params_ids_length_ptr = 0xc4;
          uint256 constant BatchTransfer1155Params_ids_length_offset = 0xa0;
          uint256 constant BatchTransfer1155Params_amounts_length_baseOffset = 0xc0;
          uint256 constant BatchTransfer1155Params_data_length_baseOffset = 0xe0;
          uint256 constant ConduitBatch1155Transfer_usable_head_size = 0x80;
          uint256 constant ConduitBatch1155Transfer_from_offset = 0x20;
          uint256 constant ConduitBatch1155Transfer_ids_head_offset = 0x60;
          uint256 constant ConduitBatch1155Transfer_amounts_head_offset = 0x80;
          uint256 constant ConduitBatch1155Transfer_ids_length_offset = 0xa0;
          uint256 constant ConduitBatch1155Transfer_amounts_length_baseOffset = 0xc0;
          uint256 constant ConduitBatch1155Transfer_calldata_baseSize = 0xc0;
          // Note: abbreviated version of above constant to adhere to line length limit.
          uint256 constant ConduitBatchTransfer_amounts_head_offset = 0x80;
          uint256 constant Invalid1155BatchTransferEncoding_ptr = 0x00;
          uint256 constant Invalid1155BatchTransferEncoding_length = 0x04;
          uint256 constant Invalid1155BatchTransferEncoding_selector = (
              0xeba2084c00000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC1155BatchTransferGenericFailure_error_signature = (
              0xafc445e200000000000000000000000000000000000000000000000000000000
          );
          uint256 constant ERC1155BatchTransferGenericFailure_token_ptr = 0x04;
          uint256 constant ERC1155BatchTransferGenericFailure_ids_offset = 0xc0;
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.7;
          /**
           * @title TokenTransferrerErrors
           */
          interface TokenTransferrerErrors {
              /**
               * @dev Revert with an error when an ERC721 transfer with amount other than
               *      one is attempted.
               */
              error InvalidERC721TransferAmount();
              /**
               * @dev Revert with an error when attempting to fulfill an order where an
               *      item has an amount of zero.
               */
              error MissingItemAmount();
              /**
               * @dev Revert with an error when attempting to fulfill an order where an
               *      item has unused parameters. This includes both the token and the
               *      identifier parameters for native transfers as well as the identifier
               *      parameter for ERC20 transfers. Note that the conduit does not
               *      perform this check, leaving it up to the calling channel to enforce
               *      when desired.
               */
              error UnusedItemParameters();
              /**
               * @dev Revert with an error when an ERC20, ERC721, or ERC1155 token
               *      transfer reverts.
               *
               * @param token      The token for which the transfer was attempted.
               * @param from       The source of the attempted transfer.
               * @param to         The recipient of the attempted transfer.
               * @param identifier The identifier for the attempted transfer.
               * @param amount     The amount for the attempted transfer.
               */
              error TokenTransferGenericFailure(
                  address token,
                  address from,
                  address to,
                  uint256 identifier,
                  uint256 amount
              );
              /**
               * @dev Revert with an error when a batch ERC1155 token transfer reverts.
               *
               * @param token       The token for which the transfer was attempted.
               * @param from        The source of the attempted transfer.
               * @param to          The recipient of the attempted transfer.
               * @param identifiers The identifiers for the attempted transfer.
               * @param amounts     The amounts for the attempted transfer.
               */
              error ERC1155BatchTransferGenericFailure(
                  address token,
                  address from,
                  address to,
                  uint256[] identifiers,
                  uint256[] amounts
              );
              /**
               * @dev Revert with an error when an ERC20 token transfer returns a falsey
               *      value.
               *
               * @param token      The token for which the ERC20 transfer was attempted.
               * @param from       The source of the attempted ERC20 transfer.
               * @param to         The recipient of the attempted ERC20 transfer.
               * @param amount     The amount for the attempted ERC20 transfer.
               */
              error BadReturnValueFromERC20OnTransfer(
                  address token,
                  address from,
                  address to,
                  uint256 amount
              );
              /**
               * @dev Revert with an error when an account being called as an assumed
               *      contract does not have code and returns no data.
               *
               * @param account The account that should contain code.
               */
              error NoContract(address account);
              /**
               * @dev Revert with an error when attempting to execute an 1155 batch
               *      transfer using calldata not produced by default ABI encoding or with
               *      different lengths for ids and amounts arrays.
               */
              error Invalid1155BatchTransferEncoding();
          }
          

          File 4 of 5: ERC721Drop
          // SPDX-License-Identifier: MIT
          // Creator: Chiru Labs
          pragma solidity ^0.8.4;
          import "./IERC721AUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/token/ERC721/IERC721ReceiverUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/utils/ContextUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/utils/StringsUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/utils/introspection/ERC165Upgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
          /**
           * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
           * the Metadata extension. Built to optimize for lower gas during batch mints.
           *
           * Assumes serials are sequentially minted starting at _startTokenId() (defaults to 0, e.g. 0, 1, 2, 3..).
           *
           * Assumes that an owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
           *
           * Assumes that the maximum token id cannot exceed 2**256 - 1 (max value of uint256).
           */
          contract ERC721AUpgradeable is Initializable, ContextUpgradeable, ERC165Upgradeable, IERC721AUpgradeable {
              using AddressUpgradeable for address;
              using StringsUpgradeable for uint256;
              // The tokenId of the next token to be minted.
              uint256 internal _currentIndex;
              // The number of tokens burned.
              uint256 internal _burnCounter;
              // Token name
              string private _name;
              // Token symbol
              string private _symbol;
              // Mapping from token ID to ownership details
              // An empty struct value does not necessarily mean the token is unowned. See _ownershipOf implementation for details.
              mapping(uint256 => TokenOwnership) internal _ownerships;
              // Mapping owner address to address data
              mapping(address => AddressData) private _addressData;
              // Mapping from token ID to approved address
              mapping(uint256 => address) private _tokenApprovals;
              // Mapping from owner to operator approvals
              mapping(address => mapping(address => bool)) private _operatorApprovals;
              function __ERC721A_init(string memory name_, string memory symbol_) internal onlyInitializing {
                  __ERC721A_init_unchained(name_, symbol_);
              }
              function __ERC721A_init_unchained(string memory name_, string memory symbol_) internal onlyInitializing {
                  _name = name_;
                  _symbol = symbol_;
                  _currentIndex = _startTokenId();
              }
              /**
               * To change the starting tokenId, please override this function.
               */
              function _startTokenId() internal view virtual returns (uint256) {
                  return 0;
              }
              /**
               * @dev Burned tokens are calculated here, use _totalMinted() if you want to count just minted tokens.
               */
              function totalSupply() public view override returns (uint256) {
                  // Counter underflow is impossible as _burnCounter cannot be incremented
                  // more than _currentIndex - _startTokenId() times
                  unchecked {
                      return _currentIndex - _burnCounter - _startTokenId();
                  }
              }
              /**
               * Returns the total amount of tokens minted in the contract.
               */
              function _totalMinted() internal view returns (uint256) {
                  // Counter underflow is impossible as _currentIndex does not decrement,
                  // and it is initialized to _startTokenId()
                  unchecked {
                      return _currentIndex - _startTokenId();
                  }
              }
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165Upgradeable, IERC165Upgradeable) returns (bool) {
                  return
                      interfaceId == type(IERC721Upgradeable).interfaceId ||
                      interfaceId == type(IERC721MetadataUpgradeable).interfaceId ||
                      super.supportsInterface(interfaceId);
              }
              /**
               * @dev See {IERC721-balanceOf}.
               */
              function balanceOf(address owner) public view override returns (uint256) {
                  if (owner == address(0)) revert BalanceQueryForZeroAddress();
                  return uint256(_addressData[owner].balance);
              }
              /**
               * Returns the number of tokens minted by `owner`.
               */
              function _numberMinted(address owner) internal view returns (uint256) {
                  return uint256(_addressData[owner].numberMinted);
              }
              /**
               * Returns the number of tokens burned by or on behalf of `owner`.
               */
              function _numberBurned(address owner) internal view returns (uint256) {
                  return uint256(_addressData[owner].numberBurned);
              }
              /**
               * Returns the auxillary data for `owner`. (e.g. number of whitelist mint slots used).
               */
              function _getAux(address owner) internal view returns (uint64) {
                  return _addressData[owner].aux;
              }
              /**
               * Sets the auxillary data for `owner`. (e.g. number of whitelist mint slots used).
               * If there are multiple variables, please pack them into a uint64.
               */
              function _setAux(address owner, uint64 aux) internal {
                  _addressData[owner].aux = aux;
              }
              /**
               * Gas spent here starts off proportional to the maximum mint batch size.
               * It gradually moves to O(1) as tokens get transferred around in the collection over time.
               */
              function _ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory) {
                  uint256 curr = tokenId;
                  unchecked {
                      if (_startTokenId() <= curr && curr < _currentIndex) {
                          TokenOwnership memory ownership = _ownerships[curr];
                          if (!ownership.burned) {
                              if (ownership.addr != address(0)) {
                                  return ownership;
                              }
                              // Invariant:
                              // There will always be an ownership that has an address and is not burned
                              // before an ownership that does not have an address and is not burned.
                              // Hence, curr will not underflow.
                              while (true) {
                                  curr--;
                                  ownership = _ownerships[curr];
                                  if (ownership.addr != address(0)) {
                                      return ownership;
                                  }
                              }
                          }
                      }
                  }
                  revert OwnerQueryForNonexistentToken();
              }
              /**
               * @dev See {IERC721-ownerOf}.
               */
              function ownerOf(uint256 tokenId) public view override returns (address) {
                  return _ownershipOf(tokenId).addr;
              }
              /**
               * @dev See {IERC721Metadata-name}.
               */
              function name() public view virtual override returns (string memory) {
                  return _name;
              }
              /**
               * @dev See {IERC721Metadata-symbol}.
               */
              function symbol() public view virtual override returns (string memory) {
                  return _symbol;
              }
              /**
               * @dev See {IERC721Metadata-tokenURI}.
               */
              function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
                  if (!_exists(tokenId)) revert URIQueryForNonexistentToken();
                  string memory baseURI = _baseURI();
                  return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : '';
              }
              /**
               * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
               * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
               * by default, can be overriden in child contracts.
               */
              function _baseURI() internal view virtual returns (string memory) {
                  return '';
              }
              /**
               * @dev See {IERC721-approve}.
               */
              function approve(address to, uint256 tokenId) public override {
                  address owner = ERC721AUpgradeable.ownerOf(tokenId);
                  if (to == owner) revert ApprovalToCurrentOwner();
                  if (_msgSender() != owner && !isApprovedForAll(owner, _msgSender())) {
                      revert ApprovalCallerNotOwnerNorApproved();
                  }
                  _approve(to, tokenId, owner);
              }
              /**
               * @dev See {IERC721-getApproved}.
               */
              function getApproved(uint256 tokenId) public view override returns (address) {
                  if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();
                  return _tokenApprovals[tokenId];
              }
              /**
               * @dev See {IERC721-setApprovalForAll}.
               */
              function setApprovalForAll(address operator, bool approved) public virtual override {
                  if (operator == _msgSender()) revert ApproveToCaller();
                  _operatorApprovals[_msgSender()][operator] = approved;
                  emit ApprovalForAll(_msgSender(), operator, approved);
              }
              /**
               * @dev See {IERC721-isApprovedForAll}.
               */
              function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
                  return _operatorApprovals[owner][operator];
              }
              /**
               * @dev See {IERC721-transferFrom}.
               */
              function transferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) public virtual override {
                  _transfer(from, to, tokenId);
              }
              /**
               * @dev See {IERC721-safeTransferFrom}.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) public virtual override {
                  safeTransferFrom(from, to, tokenId, '');
              }
              /**
               * @dev See {IERC721-safeTransferFrom}.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId,
                  bytes memory _data
              ) public virtual override {
                  _transfer(from, to, tokenId);
                  if (to.isContract() && !_checkContractOnERC721Received(from, to, tokenId, _data)) {
                      revert TransferToNonERC721ReceiverImplementer();
                  }
              }
              /**
               * @dev Returns whether `tokenId` exists.
               *
               * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
               *
               * Tokens start existing when they are minted (`_mint`),
               */
              function _exists(uint256 tokenId) internal view returns (bool) {
                  return _startTokenId() <= tokenId && tokenId < _currentIndex && !_ownerships[tokenId].burned;
              }
              /**
               * @dev Equivalent to `_safeMint(to, quantity, '')`.
               */
              function _safeMint(address to, uint256 quantity) internal {
                  _safeMint(to, quantity, '');
              }
              /**
               * @dev Safely mints `quantity` tokens and transfers them to `to`.
               *
               * Requirements:
               *
               * - If `to` refers to a smart contract, it must implement
               *   {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
               * - `quantity` must be greater than 0.
               *
               * Emits a {Transfer} event.
               */
              function _safeMint(
                  address to,
                  uint256 quantity,
                  bytes memory _data
              ) internal {
                  uint256 startTokenId = _currentIndex;
                  if (to == address(0)) revert MintToZeroAddress();
                  if (quantity == 0) revert MintZeroQuantity();
                  _beforeTokenTransfers(address(0), to, startTokenId, quantity);
                  // Overflows are incredibly unrealistic.
                  // balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1
                  // updatedIndex overflows if _currentIndex + quantity > 1.2e77 (2**256) - 1
                  unchecked {
                      _addressData[to].balance += uint64(quantity);
                      _addressData[to].numberMinted += uint64(quantity);
                      _ownerships[startTokenId].addr = to;
                      _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);
                      uint256 updatedIndex = startTokenId;
                      uint256 end = updatedIndex + quantity;
                      if (to.isContract()) {
                          do {
                              emit Transfer(address(0), to, updatedIndex);
                              if (!_checkContractOnERC721Received(address(0), to, updatedIndex++, _data)) {
                                  revert TransferToNonERC721ReceiverImplementer();
                              }
                          } while (updatedIndex != end);
                          // Reentrancy protection
                          if (_currentIndex != startTokenId) revert();
                      } else {
                          do {
                              emit Transfer(address(0), to, updatedIndex++);
                          } while (updatedIndex != end);
                      }
                      _currentIndex = updatedIndex;
                  }
                  _afterTokenTransfers(address(0), to, startTokenId, quantity);
              }
              /**
               * @dev Mints `quantity` tokens and transfers them to `to`.
               *
               * Requirements:
               *
               * - `to` cannot be the zero address.
               * - `quantity` must be greater than 0.
               *
               * Emits a {Transfer} event.
               */
              function _mint(address to, uint256 quantity) internal {
                  uint256 startTokenId = _currentIndex;
                  if (to == address(0)) revert MintToZeroAddress();
                  if (quantity == 0) revert MintZeroQuantity();
                  _beforeTokenTransfers(address(0), to, startTokenId, quantity);
                  // Overflows are incredibly unrealistic.
                  // balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1
                  // updatedIndex overflows if _currentIndex + quantity > 1.2e77 (2**256) - 1
                  unchecked {
                      _addressData[to].balance += uint64(quantity);
                      _addressData[to].numberMinted += uint64(quantity);
                      _ownerships[startTokenId].addr = to;
                      _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);
                      uint256 updatedIndex = startTokenId;
                      uint256 end = updatedIndex + quantity;
                      do {
                          emit Transfer(address(0), to, updatedIndex++);
                      } while (updatedIndex != end);
                      _currentIndex = updatedIndex;
                  }
                  _afterTokenTransfers(address(0), to, startTokenId, quantity);
              }
              /**
               * @dev Transfers `tokenId` from `from` to `to`.
               *
               * Requirements:
               *
               * - `to` cannot be the zero address.
               * - `tokenId` token must be owned by `from`.
               *
               * Emits a {Transfer} event.
               */
              function _transfer(
                  address from,
                  address to,
                  uint256 tokenId
              ) private {
                  TokenOwnership memory prevOwnership = _ownershipOf(tokenId);
                  if (prevOwnership.addr != from) revert TransferFromIncorrectOwner();
                  bool isApprovedOrOwner = (_msgSender() == from ||
                      isApprovedForAll(from, _msgSender()) ||
                      getApproved(tokenId) == _msgSender());
                  if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
                  if (to == address(0)) revert TransferToZeroAddress();
                  _beforeTokenTransfers(from, to, tokenId, 1);
                  // Clear approvals from the previous owner
                  _approve(address(0), tokenId, from);
                  // Underflow of the sender's balance is impossible because we check for
                  // ownership above and the recipient's balance can't realistically overflow.
                  // Counter overflow is incredibly unrealistic as tokenId would have to be 2**256.
                  unchecked {
                      _addressData[from].balance -= 1;
                      _addressData[to].balance += 1;
                      TokenOwnership storage currSlot = _ownerships[tokenId];
                      currSlot.addr = to;
                      currSlot.startTimestamp = uint64(block.timestamp);
                      // If the ownership slot of tokenId+1 is not explicitly set, that means the transfer initiator owns it.
                      // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
                      uint256 nextTokenId = tokenId + 1;
                      TokenOwnership storage nextSlot = _ownerships[nextTokenId];
                      if (nextSlot.addr == address(0)) {
                          // This will suffice for checking _exists(nextTokenId),
                          // as a burned slot cannot contain the zero address.
                          if (nextTokenId != _currentIndex) {
                              nextSlot.addr = from;
                              nextSlot.startTimestamp = prevOwnership.startTimestamp;
                          }
                      }
                  }
                  emit Transfer(from, to, tokenId);
                  _afterTokenTransfers(from, to, tokenId, 1);
              }
              /**
               * @dev Equivalent to `_burn(tokenId, false)`.
               */
              function _burn(uint256 tokenId) internal virtual {
                  _burn(tokenId, false);
              }
              /**
               * @dev Destroys `tokenId`.
               * The approval is cleared when the token is burned.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               *
               * Emits a {Transfer} event.
               */
              function _burn(uint256 tokenId, bool approvalCheck) internal virtual {
                  TokenOwnership memory prevOwnership = _ownershipOf(tokenId);
                  address from = prevOwnership.addr;
                  if (approvalCheck) {
                      bool isApprovedOrOwner = (_msgSender() == from ||
                          isApprovedForAll(from, _msgSender()) ||
                          getApproved(tokenId) == _msgSender());
                      if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
                  }
                  _beforeTokenTransfers(from, address(0), tokenId, 1);
                  // Clear approvals from the previous owner
                  _approve(address(0), tokenId, from);
                  // Underflow of the sender's balance is impossible because we check for
                  // ownership above and the recipient's balance can't realistically overflow.
                  // Counter overflow is incredibly unrealistic as tokenId would have to be 2**256.
                  unchecked {
                      AddressData storage addressData = _addressData[from];
                      addressData.balance -= 1;
                      addressData.numberBurned += 1;
                      // Keep track of who burned the token, and the timestamp of burning.
                      TokenOwnership storage currSlot = _ownerships[tokenId];
                      currSlot.addr = from;
                      currSlot.startTimestamp = uint64(block.timestamp);
                      currSlot.burned = true;
                      // If the ownership slot of tokenId+1 is not explicitly set, that means the burn initiator owns it.
                      // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
                      uint256 nextTokenId = tokenId + 1;
                      TokenOwnership storage nextSlot = _ownerships[nextTokenId];
                      if (nextSlot.addr == address(0)) {
                          // This will suffice for checking _exists(nextTokenId),
                          // as a burned slot cannot contain the zero address.
                          if (nextTokenId != _currentIndex) {
                              nextSlot.addr = from;
                              nextSlot.startTimestamp = prevOwnership.startTimestamp;
                          }
                      }
                  }
                  emit Transfer(from, address(0), tokenId);
                  _afterTokenTransfers(from, address(0), tokenId, 1);
                  // Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.
                  unchecked {
                      _burnCounter++;
                  }
              }
              /**
               * @dev Approve `to` to operate on `tokenId`
               *
               * Emits a {Approval} event.
               */
              function _approve(
                  address to,
                  uint256 tokenId,
                  address owner
              ) private {
                  _tokenApprovals[tokenId] = to;
                  emit Approval(owner, to, tokenId);
              }
              /**
               * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target contract.
               *
               * @param from address representing the previous owner of the given token ID
               * @param to target address that will receive the tokens
               * @param tokenId uint256 ID of the token to be transferred
               * @param _data bytes optional data to send along with the call
               * @return bool whether the call correctly returned the expected magic value
               */
              function _checkContractOnERC721Received(
                  address from,
                  address to,
                  uint256 tokenId,
                  bytes memory _data
              ) private returns (bool) {
                  try IERC721ReceiverUpgradeable(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
                      return retval == IERC721ReceiverUpgradeable(to).onERC721Received.selector;
                  } catch (bytes memory reason) {
                      if (reason.length == 0) {
                          revert TransferToNonERC721ReceiverImplementer();
                      } else {
                          assembly {
                              revert(add(32, reason), mload(reason))
                          }
                      }
                  }
              }
              /**
               * @dev Hook that is called before a set of serially-ordered token ids are about to be transferred. This includes minting.
               * And also called before burning one token.
               *
               * startTokenId - the first token id to be transferred
               * quantity - the amount to be transferred
               *
               * Calling conditions:
               *
               * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
               * transferred to `to`.
               * - When `from` is zero, `tokenId` will be minted for `to`.
               * - When `to` is zero, `tokenId` will be burned by `from`.
               * - `from` and `to` are never both zero.
               */
              function _beforeTokenTransfers(
                  address from,
                  address to,
                  uint256 startTokenId,
                  uint256 quantity
              ) internal virtual {}
              /**
               * @dev Hook that is called after a set of serially-ordered token ids have been transferred. This includes
               * minting.
               * And also called after one token has been burned.
               *
               * startTokenId - the first token id to be transferred
               * quantity - the amount to be transferred
               *
               * Calling conditions:
               *
               * - When `from` and `to` are both non-zero, `from`'s `tokenId` has been
               * transferred to `to`.
               * - When `from` is zero, `tokenId` has been minted for `to`.
               * - When `to` is zero, `tokenId` has been burned by `from`.
               * - `from` and `to` are never both zero.
               */
              function _afterTokenTransfers(
                  address from,
                  address to,
                  uint256 startTokenId,
                  uint256 quantity
              ) internal virtual {}
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[42] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // Creator: Chiru Labs
          pragma solidity ^0.8.4;
          import "@openzeppelin/contracts-upgradeable/token/ERC721/IERC721Upgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/token/ERC721/extensions/IERC721MetadataUpgradeable.sol";
          /**
           * @dev Interface of an ERC721A compliant contract.
           */
          interface IERC721AUpgradeable is IERC721Upgradeable, IERC721MetadataUpgradeable {
              /**
               * The caller must own the token or be an approved operator.
               */
              error ApprovalCallerNotOwnerNorApproved();
              /**
               * The token does not exist.
               */
              error ApprovalQueryForNonexistentToken();
              /**
               * The caller cannot approve to their own address.
               */
              error ApproveToCaller();
              /**
               * The caller cannot approve to the current owner.
               */
              error ApprovalToCurrentOwner();
              /**
               * Cannot query the balance for the zero address.
               */
              error BalanceQueryForZeroAddress();
              /**
               * Cannot mint to the zero address.
               */
              error MintToZeroAddress();
              /**
               * The quantity of tokens minted must be more than zero.
               */
              error MintZeroQuantity();
              /**
               * The token does not exist.
               */
              error OwnerQueryForNonexistentToken();
              /**
               * The caller must own the token or be an approved operator.
               */
              error TransferCallerNotOwnerNorApproved();
              /**
               * The token must be owned by `from`.
               */
              error TransferFromIncorrectOwner();
              /**
               * Cannot safely transfer to a contract that does not implement the ERC721Receiver interface.
               */
              error TransferToNonERC721ReceiverImplementer();
              /**
               * Cannot transfer to the zero address.
               */
              error TransferToZeroAddress();
              /**
               * The token does not exist.
               */
              error URIQueryForNonexistentToken();
              // Compiler will pack this into a single 256bit word.
              struct TokenOwnership {
                  // The address of the owner.
                  address addr;
                  // Keeps track of the start time of ownership with minimal overhead for tokenomics.
                  uint64 startTimestamp;
                  // Whether the token has been burned.
                  bool burned;
              }
              // Compiler will pack this into a single 256bit word.
              struct AddressData {
                  // Realistically, 2**64-1 is more than enough.
                  uint64 balance;
                  // Keeps track of mint count with minimal overhead for tokenomics.
                  uint64 numberMinted;
                  // Keeps track of burn count with minimal overhead for tokenomics.
                  uint64 numberBurned;
                  // For miscellaneous variable(s) pertaining to the address
                  // (e.g. number of whitelist mint slots used).
                  // If there are multiple variables, please pack them into a uint64.
                  uint64 aux;
              }
              /**
               * @dev Returns the total amount of tokens stored by the contract.
               * @dev Burned tokens are calculated here, use _totalMinted() if you want to count just minted tokens.
               */
              function totalSupply() external view returns (uint256);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (access/AccessControl.sol)
          pragma solidity ^0.8.0;
          import "./IAccessControlUpgradeable.sol";
          import "../utils/ContextUpgradeable.sol";
          import "../utils/StringsUpgradeable.sol";
          import "../utils/introspection/ERC165Upgradeable.sol";
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Contract module that allows children to implement role-based access
           * control mechanisms. This is a lightweight version that doesn't allow enumerating role
           * members except through off-chain means by accessing the contract event logs. Some
           * applications may benefit from on-chain enumerability, for those cases see
           * {AccessControlEnumerable}.
           *
           * Roles are referred to by their `bytes32` identifier. These should be exposed
           * in the external API and be unique. The best way to achieve this is by
           * using `public constant` hash digests:
           *
           * ```
           * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
           * ```
           *
           * Roles can be used to represent a set of permissions. To restrict access to a
           * function call, use {hasRole}:
           *
           * ```
           * function foo() public {
           *     require(hasRole(MY_ROLE, msg.sender));
           *     ...
           * }
           * ```
           *
           * Roles can be granted and revoked dynamically via the {grantRole} and
           * {revokeRole} functions. Each role has an associated admin role, and only
           * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
           *
           * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
           * that only accounts with this role will be able to grant or revoke other
           * roles. More complex role relationships can be created by using
           * {_setRoleAdmin}.
           *
           * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
           * grant and revoke this role. Extra precautions should be taken to secure
           * accounts that have been granted it.
           */
          abstract contract AccessControlUpgradeable is Initializable, ContextUpgradeable, IAccessControlUpgradeable, ERC165Upgradeable {
              function __AccessControl_init() internal onlyInitializing {
              }
              function __AccessControl_init_unchained() internal onlyInitializing {
              }
              struct RoleData {
                  mapping(address => bool) members;
                  bytes32 adminRole;
              }
              mapping(bytes32 => RoleData) private _roles;
              bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
              /**
               * @dev Modifier that checks that an account has a specific role. Reverts
               * with a standardized message including the required role.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               *
               * _Available since v4.1._
               */
              modifier onlyRole(bytes32 role) {
                  _checkRole(role);
                  _;
              }
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IAccessControlUpgradeable).interfaceId || super.supportsInterface(interfaceId);
              }
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
                  return _roles[role].members[account];
              }
              /**
               * @dev Revert with a standard message if `_msgSender()` is missing `role`.
               * Overriding this function changes the behavior of the {onlyRole} modifier.
               *
               * Format of the revert message is described in {_checkRole}.
               *
               * _Available since v4.6._
               */
              function _checkRole(bytes32 role) internal view virtual {
                  _checkRole(role, _msgSender());
              }
              /**
               * @dev Revert with a standard message if `account` is missing `role`.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               */
              function _checkRole(bytes32 role, address account) internal view virtual {
                  if (!hasRole(role, account)) {
                      revert(
                          string(
                              abi.encodePacked(
                                  "AccessControl: account ",
                                  StringsUpgradeable.toHexString(uint160(account), 20),
                                  " is missing role ",
                                  StringsUpgradeable.toHexString(uint256(role), 32)
                              )
                          )
                      );
                  }
              }
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
                  return _roles[role].adminRole;
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _grantRole(role, account);
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _revokeRole(role, account);
              }
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been revoked `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               */
              function renounceRole(bytes32 role, address account) public virtual override {
                  require(account == _msgSender(), "AccessControl: can only renounce roles for self");
                  _revokeRole(role, account);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event. Note that unlike {grantRole}, this function doesn't perform any
               * checks on the calling account.
               *
               * [WARNING]
               * ====
               * This function should only be called from the constructor when setting
               * up the initial roles for the system.
               *
               * Using this function in any other way is effectively circumventing the admin
               * system imposed by {AccessControl}.
               * ====
               *
               * NOTE: This function is deprecated in favor of {_grantRole}.
               */
              function _setupRole(bytes32 role, address account) internal virtual {
                  _grantRole(role, account);
              }
              /**
               * @dev Sets `adminRole` as ``role``'s admin role.
               *
               * Emits a {RoleAdminChanged} event.
               */
              function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
                  bytes32 previousAdminRole = getRoleAdmin(role);
                  _roles[role].adminRole = adminRole;
                  emit RoleAdminChanged(role, previousAdminRole, adminRole);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * Internal function without access restriction.
               */
              function _grantRole(bytes32 role, address account) internal virtual {
                  if (!hasRole(role, account)) {
                      _roles[role].members[account] = true;
                      emit RoleGranted(role, account, _msgSender());
                  }
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * Internal function without access restriction.
               */
              function _revokeRole(bytes32 role, address account) internal virtual {
                  if (hasRole(role, account)) {
                      _roles[role].members[account] = false;
                      emit RoleRevoked(role, account, _msgSender());
                  }
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[49] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev External interface of AccessControl declared to support ERC165 detection.
           */
          interface IAccessControlUpgradeable {
              /**
               * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
               *
               * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
               * {RoleAdminChanged} not being emitted signaling this.
               *
               * _Available since v3.1._
               */
              event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
              /**
               * @dev Emitted when `account` is granted `role`.
               *
               * `sender` is the account that originated the contract call, an admin role
               * bearer except when using {AccessControl-_setupRole}.
               */
              event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Emitted when `account` is revoked `role`.
               *
               * `sender` is the account that originated the contract call:
               *   - if using `revokeRole`, it is the admin role bearer
               *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
               */
              event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) external view returns (bool);
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {AccessControl-_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) external view returns (bytes32);
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function grantRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function revokeRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been granted `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               */
              function renounceRole(bytes32 role, address account) external;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/IERC2981.sol)
          pragma solidity ^0.8.0;
          import "../utils/introspection/IERC165Upgradeable.sol";
          /**
           * @dev Interface for the NFT Royalty Standard.
           *
           * A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal
           * support for royalty payments across all NFT marketplaces and ecosystem participants.
           *
           * _Available since v4.5._
           */
          interface IERC2981Upgradeable is IERC165Upgradeable {
              /**
               * @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of
               * exchange. The royalty amount is denominated and should be payed in that same unit of exchange.
               */
              function royaltyInfo(uint256 tokenId, uint256 salePrice)
                  external
                  view
                  returns (address receiver, uint256 royaltyAmount);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
           * proxy whose upgrades are fully controlled by the current implementation.
           */
          interface IERC1822ProxiableUpgradeable {
              /**
               * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
               * address.
               *
               * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
               * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
               * function revert if invoked through a proxy.
               */
              function proxiableUUID() external view returns (bytes32);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
          pragma solidity ^0.8.2;
          import "../beacon/IBeaconUpgradeable.sol";
          import "../../interfaces/draft-IERC1822Upgradeable.sol";
          import "../../utils/AddressUpgradeable.sol";
          import "../../utils/StorageSlotUpgradeable.sol";
          import "../utils/Initializable.sol";
          /**
           * @dev This abstract contract provides getters and event emitting update functions for
           * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
           *
           * _Available since v4.1._
           *
           * @custom:oz-upgrades-unsafe-allow delegatecall
           */
          abstract contract ERC1967UpgradeUpgradeable is Initializable {
              function __ERC1967Upgrade_init() internal onlyInitializing {
              }
              function __ERC1967Upgrade_init_unchained() internal onlyInitializing {
              }
              // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
              bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
              /**
               * @dev Storage slot with the address of the current implementation.
               * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
              /**
               * @dev Emitted when the implementation is upgraded.
               */
              event Upgraded(address indexed implementation);
              /**
               * @dev Returns the current implementation address.
               */
              function _getImplementation() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 implementation slot.
               */
              function _setImplementation(address newImplementation) private {
                  require(AddressUpgradeable.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                  StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
              }
              /**
               * @dev Perform implementation upgrade
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeTo(address newImplementation) internal {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
              }
              /**
               * @dev Perform implementation upgrade with additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCall(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _upgradeTo(newImplementation);
                  if (data.length > 0 || forceCall) {
                      _functionDelegateCall(newImplementation, data);
                  }
              }
              /**
               * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCallUUPS(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  // Upgrades from old implementations will perform a rollback test. This test requires the new
                  // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                  // this special case will break upgrade paths from old UUPS implementation to new ones.
                  if (StorageSlotUpgradeable.getBooleanSlot(_ROLLBACK_SLOT).value) {
                      _setImplementation(newImplementation);
                  } else {
                      try IERC1822ProxiableUpgradeable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                          require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                      } catch {
                          revert("ERC1967Upgrade: new implementation is not UUPS");
                      }
                      _upgradeToAndCall(newImplementation, data, forceCall);
                  }
              }
              /**
               * @dev Storage slot with the admin of the contract.
               * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
              /**
               * @dev Emitted when the admin account has changed.
               */
              event AdminChanged(address previousAdmin, address newAdmin);
              /**
               * @dev Returns the current admin.
               */
              function _getAdmin() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 admin slot.
               */
              function _setAdmin(address newAdmin) private {
                  require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                  StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
              }
              /**
               * @dev Changes the admin of the proxy.
               *
               * Emits an {AdminChanged} event.
               */
              function _changeAdmin(address newAdmin) internal {
                  emit AdminChanged(_getAdmin(), newAdmin);
                  _setAdmin(newAdmin);
              }
              /**
               * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
               * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
               */
              bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
              /**
               * @dev Emitted when the beacon is upgraded.
               */
              event BeaconUpgraded(address indexed beacon);
              /**
               * @dev Returns the current beacon.
               */
              function _getBeacon() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value;
              }
              /**
               * @dev Stores a new beacon in the EIP1967 beacon slot.
               */
              function _setBeacon(address newBeacon) private {
                  require(AddressUpgradeable.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                  require(
                      AddressUpgradeable.isContract(IBeaconUpgradeable(newBeacon).implementation()),
                      "ERC1967: beacon implementation is not a contract"
                  );
                  StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value = newBeacon;
              }
              /**
               * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
               * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
               *
               * Emits a {BeaconUpgraded} event.
               */
              function _upgradeBeaconToAndCall(
                  address newBeacon,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _setBeacon(newBeacon);
                  emit BeaconUpgraded(newBeacon);
                  if (data.length > 0 || forceCall) {
                      _functionDelegateCall(IBeaconUpgradeable(newBeacon).implementation(), data);
                  }
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
                  require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev This is the interface that {BeaconProxy} expects of its beacon.
           */
          interface IBeaconUpgradeable {
              /**
               * @dev Must return an address that can be used as a delegate call target.
               *
               * {BeaconProxy} will check that this address is a contract.
               */
              function implementation() external view returns (address);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/utils/Initializable.sol)
          pragma solidity ^0.8.0;
          import "../../utils/AddressUpgradeable.sol";
          /**
           * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
           * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
           * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
           * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
           *
           * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
           * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
           *
           * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
           * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
           *
           * [CAUTION]
           * ====
           * Avoid leaving a contract uninitialized.
           *
           * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
           * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
           * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
           *
           * [.hljs-theme-light.nopadding]
           * ```
           * /// @custom:oz-upgrades-unsafe-allow constructor
           * constructor() initializer {}
           * ```
           * ====
           */
          abstract contract Initializable {
              /**
               * @dev Indicates that the contract has been initialized.
               */
              bool private _initialized;
              /**
               * @dev Indicates that the contract is in the process of being initialized.
               */
              bool private _initializing;
              /**
               * @dev Modifier to protect an initializer function from being invoked twice.
               */
              modifier initializer() {
                  // If the contract is initializing we ignore whether _initialized is set in order to support multiple
                  // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
                  // contract may have been reentered.
                  require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");
                  bool isTopLevelCall = !_initializing;
                  if (isTopLevelCall) {
                      _initializing = true;
                      _initialized = true;
                  }
                  _;
                  if (isTopLevelCall) {
                      _initializing = false;
                  }
              }
              /**
               * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
               * {initializer} modifier, directly or indirectly.
               */
              modifier onlyInitializing() {
                  require(_initializing, "Initializable: contract is not initializing");
                  _;
              }
              function _isConstructor() private view returns (bool) {
                  return !AddressUpgradeable.isContract(address(this));
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/utils/UUPSUpgradeable.sol)
          pragma solidity ^0.8.0;
          import "../../interfaces/draft-IERC1822Upgradeable.sol";
          import "../ERC1967/ERC1967UpgradeUpgradeable.sol";
          import "./Initializable.sol";
          /**
           * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
           * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
           *
           * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
           * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
           * `UUPSUpgradeable` with a custom implementation of upgrades.
           *
           * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
           *
           * _Available since v4.1._
           */
          abstract contract UUPSUpgradeable is Initializable, IERC1822ProxiableUpgradeable, ERC1967UpgradeUpgradeable {
              function __UUPSUpgradeable_init() internal onlyInitializing {
              }
              function __UUPSUpgradeable_init_unchained() internal onlyInitializing {
              }
              /// @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
              address private immutable __self = address(this);
              /**
               * @dev Check that the execution is being performed through a delegatecall call and that the execution context is
               * a proxy contract with an implementation (as defined in ERC1967) pointing to self. This should only be the case
               * for UUPS and transparent proxies that are using the current contract as their implementation. Execution of a
               * function through ERC1167 minimal proxies (clones) would not normally pass this test, but is not guaranteed to
               * fail.
               */
              modifier onlyProxy() {
                  require(address(this) != __self, "Function must be called through delegatecall");
                  require(_getImplementation() == __self, "Function must be called through active proxy");
                  _;
              }
              /**
               * @dev Check that the execution is not being performed through a delegate call. This allows a function to be
               * callable on the implementing contract but not through proxies.
               */
              modifier notDelegated() {
                  require(address(this) == __self, "UUPSUpgradeable: must not be called through delegatecall");
                  _;
              }
              /**
               * @dev Implementation of the ERC1822 {proxiableUUID} function. This returns the storage slot used by the
               * implementation. It is used to validate that the this implementation remains valid after an upgrade.
               *
               * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
               * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
               * function revert if invoked through a proxy. This is guaranteed by the `notDelegated` modifier.
               */
              function proxiableUUID() external view virtual override notDelegated returns (bytes32) {
                  return _IMPLEMENTATION_SLOT;
              }
              /**
               * @dev Upgrade the implementation of the proxy to `newImplementation`.
               *
               * Calls {_authorizeUpgrade}.
               *
               * Emits an {Upgraded} event.
               */
              function upgradeTo(address newImplementation) external virtual onlyProxy {
                  _authorizeUpgrade(newImplementation);
                  _upgradeToAndCallUUPS(newImplementation, new bytes(0), false);
              }
              /**
               * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
               * encoded in `data`.
               *
               * Calls {_authorizeUpgrade}.
               *
               * Emits an {Upgraded} event.
               */
              function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual onlyProxy {
                  _authorizeUpgrade(newImplementation);
                  _upgradeToAndCallUUPS(newImplementation, data, true);
              }
              /**
               * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
               * {upgradeTo} and {upgradeToAndCall}.
               *
               * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
               *
               * ```solidity
               * function _authorizeUpgrade(address) internal override onlyOwner {}
               * ```
               */
              function _authorizeUpgrade(address newImplementation) internal virtual;
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
          pragma solidity ^0.8.0;
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Contract module that helps prevent reentrant calls to a function.
           *
           * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
           * available, which can be applied to functions to make sure there are no nested
           * (reentrant) calls to them.
           *
           * Note that because there is a single `nonReentrant` guard, functions marked as
           * `nonReentrant` may not call one another. This can be worked around by making
           * those functions `private`, and then adding `external` `nonReentrant` entry
           * points to them.
           *
           * TIP: If you would like to learn more about reentrancy and alternative ways
           * to protect against it, check out our blog post
           * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
           */
          abstract contract ReentrancyGuardUpgradeable is Initializable {
              // Booleans are more expensive than uint256 or any type that takes up a full
              // word because each write operation emits an extra SLOAD to first read the
              // slot's contents, replace the bits taken up by the boolean, and then write
              // back. This is the compiler's defense against contract upgrades and
              // pointer aliasing, and it cannot be disabled.
              // The values being non-zero value makes deployment a bit more expensive,
              // but in exchange the refund on every call to nonReentrant will be lower in
              // amount. Since refunds are capped to a percentage of the total
              // transaction's gas, it is best to keep them low in cases like this one, to
              // increase the likelihood of the full refund coming into effect.
              uint256 private constant _NOT_ENTERED = 1;
              uint256 private constant _ENTERED = 2;
              uint256 private _status;
              function __ReentrancyGuard_init() internal onlyInitializing {
                  __ReentrancyGuard_init_unchained();
              }
              function __ReentrancyGuard_init_unchained() internal onlyInitializing {
                  _status = _NOT_ENTERED;
              }
              /**
               * @dev Prevents a contract from calling itself, directly or indirectly.
               * Calling a `nonReentrant` function from another `nonReentrant`
               * function is not supported. It is possible to prevent this from happening
               * by making the `nonReentrant` function external, and making it call a
               * `private` function that does the actual work.
               */
              modifier nonReentrant() {
                  // On the first call to nonReentrant, _notEntered will be true
                  require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                  // Any calls to nonReentrant after this point will fail
                  _status = _ENTERED;
                  _;
                  // By storing the original value once again, a refund is triggered (see
                  // https://eips.ethereum.org/EIPS/eip-2200)
                  _status = _NOT_ENTERED;
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[49] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)
          pragma solidity ^0.8.0;
          /**
           * @title ERC721 token receiver interface
           * @dev Interface for any contract that wants to support safeTransfers
           * from ERC721 asset contracts.
           */
          interface IERC721ReceiverUpgradeable {
              /**
               * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
               * by `operator` from `from`, this function is called.
               *
               * It must return its Solidity selector to confirm the token transfer.
               * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
               *
               * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
               */
              function onERC721Received(
                  address operator,
                  address from,
                  uint256 tokenId,
                  bytes calldata data
              ) external returns (bytes4);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)
          pragma solidity ^0.8.0;
          import "../../utils/introspection/IERC165Upgradeable.sol";
          /**
           * @dev Required interface of an ERC721 compliant contract.
           */
          interface IERC721Upgradeable is IERC165Upgradeable {
              /**
               * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
               */
              event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
              /**
               * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
               */
              event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
              /**
               * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
               */
              event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
              /**
               * @dev Returns the number of tokens in ``owner``'s account.
               */
              function balanceOf(address owner) external view returns (uint256 balance);
              /**
               * @dev Returns the owner of the `tokenId` token.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               */
              function ownerOf(uint256 tokenId) external view returns (address owner);
              /**
               * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
               * are aware of the ERC721 protocol to prevent tokens from being forever locked.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `tokenId` token must exist and be owned by `from`.
               * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
               * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
               *
               * Emits a {Transfer} event.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) external;
              /**
               * @dev Transfers `tokenId` token from `from` to `to`.
               *
               * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `tokenId` token must be owned by `from`.
               * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
               *
               * Emits a {Transfer} event.
               */
              function transferFrom(
                  address from,
                  address to,
                  uint256 tokenId
              ) external;
              /**
               * @dev Gives permission to `to` to transfer `tokenId` token to another account.
               * The approval is cleared when the token is transferred.
               *
               * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
               *
               * Requirements:
               *
               * - The caller must own the token or be an approved operator.
               * - `tokenId` must exist.
               *
               * Emits an {Approval} event.
               */
              function approve(address to, uint256 tokenId) external;
              /**
               * @dev Returns the account approved for `tokenId` token.
               *
               * Requirements:
               *
               * - `tokenId` must exist.
               */
              function getApproved(uint256 tokenId) external view returns (address operator);
              /**
               * @dev Approve or remove `operator` as an operator for the caller.
               * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
               *
               * Requirements:
               *
               * - The `operator` cannot be the caller.
               *
               * Emits an {ApprovalForAll} event.
               */
              function setApprovalForAll(address operator, bool _approved) external;
              /**
               * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
               *
               * See {setApprovalForAll}
               */
              function isApprovedForAll(address owner, address operator) external view returns (bool);
              /**
               * @dev Safely transfers `tokenId` token from `from` to `to`.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `tokenId` token must exist and be owned by `from`.
               * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
               * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
               *
               * Emits a {Transfer} event.
               */
              function safeTransferFrom(
                  address from,
                  address to,
                  uint256 tokenId,
                  bytes calldata data
              ) external;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)
          pragma solidity ^0.8.0;
          import "../IERC721Upgradeable.sol";
          /**
           * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
           * @dev See https://eips.ethereum.org/EIPS/eip-721
           */
          interface IERC721MetadataUpgradeable is IERC721Upgradeable {
              /**
               * @dev Returns the token collection name.
               */
              function name() external view returns (string memory);
              /**
               * @dev Returns the token collection symbol.
               */
              function symbol() external view returns (string memory);
              /**
               * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
               */
              function tokenURI(uint256 tokenId) external view returns (string memory);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)
          pragma solidity ^0.8.1;
          /**
           * @dev Collection of functions related to the address type
           */
          library AddressUpgradeable {
              /**
               * @dev Returns true if `account` is a contract.
               *
               * [IMPORTANT]
               * ====
               * It is unsafe to assume that an address for which this function returns
               * false is an externally-owned account (EOA) and not a contract.
               *
               * Among others, `isContract` will return false for the following
               * types of addresses:
               *
               *  - an externally-owned account
               *  - a contract in construction
               *  - an address where a contract will be created
               *  - an address where a contract lived, but was destroyed
               * ====
               *
               * [IMPORTANT]
               * ====
               * You shouldn't rely on `isContract` to protect against flash loan attacks!
               *
               * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
               * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
               * constructor.
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize/address.code.length, which returns 0
                  // for contracts in construction, since the code is only stored at the end
                  // of the constructor execution.
                  return account.code.length > 0;
              }
              /**
               * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
               * `recipient`, forwarding all available gas and reverting on errors.
               *
               * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
               * of certain opcodes, possibly making contracts go over the 2300 gas limit
               * imposed by `transfer`, making them unable to receive funds via
               * `transfer`. {sendValue} removes this limitation.
               *
               * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
               *
               * IMPORTANT: because control is transferred to `recipient`, care must be
               * taken to not create reentrancy vulnerabilities. Consider using
               * {ReentrancyGuard} or the
               * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
               */
              function sendValue(address payable recipient, uint256 amount) internal {
                  require(address(this).balance >= amount, "Address: insufficient balance");
                  (bool success, ) = recipient.call{value: amount}("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
              /**
               * @dev Performs a Solidity function call using a low level `call`. A
               * plain `call` is an unsafe replacement for a function call: use this
               * function instead.
               *
               * If `target` reverts with a revert reason, it is bubbled up by this
               * function (like regular Solidity function calls).
               *
               * Returns the raw returned data. To convert to the expected return value,
               * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
               *
               * Requirements:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionCall(target, data, "Address: low-level call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  require(isContract(target), "Address: call to non-contract");
                  (bool success, bytes memory returndata) = target.call{value: value}(data);
                  return verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  require(isContract(target), "Address: static call to non-contract");
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
               * revert reason using the provided one.
               *
               * _Available since v4.3._
               */
              function verifyCallResult(
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal pure returns (bytes memory) {
                  if (success) {
                      return returndata;
                  } else {
                      // Look for revert reason and bubble it up if present
                      if (returndata.length > 0) {
                          // The easiest way to bubble the revert reason is using memory via assembly
                          assembly {
                              let returndata_size := mload(returndata)
                              revert(add(32, returndata), returndata_size)
                          }
                      } else {
                          revert(errorMessage);
                      }
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
          pragma solidity ^0.8.0;
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract ContextUpgradeable is Initializable {
              function __Context_init() internal onlyInitializing {
              }
              function __Context_init_unchained() internal onlyInitializing {
              }
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/StorageSlot.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Library for reading and writing primitive types to specific storage slots.
           *
           * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
           * This library helps with reading and writing to such slots without the need for inline assembly.
           *
           * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
           *
           * Example usage to set ERC1967 implementation slot:
           * ```
           * contract ERC1967 {
           *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
           *
           *     function _getImplementation() internal view returns (address) {
           *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
           *     }
           *
           *     function _setImplementation(address newImplementation) internal {
           *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
           *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
           *     }
           * }
           * ```
           *
           * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
           */
          library StorageSlotUpgradeable {
              struct AddressSlot {
                  address value;
              }
              struct BooleanSlot {
                  bool value;
              }
              struct Bytes32Slot {
                  bytes32 value;
              }
              struct Uint256Slot {
                  uint256 value;
              }
              /**
               * @dev Returns an `AddressSlot` with member `value` located at `slot`.
               */
              function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
               */
              function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
               */
              function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
               */
              function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev String operations.
           */
          library StringsUpgradeable {
              bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
              /**
               * @dev Converts a `uint256` to its ASCII `string` decimal representation.
               */
              function toString(uint256 value) internal pure returns (string memory) {
                  // Inspired by OraclizeAPI's implementation - MIT licence
                  // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                  if (value == 0) {
                      return "0";
                  }
                  uint256 temp = value;
                  uint256 digits;
                  while (temp != 0) {
                      digits++;
                      temp /= 10;
                  }
                  bytes memory buffer = new bytes(digits);
                  while (value != 0) {
                      digits -= 1;
                      buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                      value /= 10;
                  }
                  return string(buffer);
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
               */
              function toHexString(uint256 value) internal pure returns (string memory) {
                  if (value == 0) {
                      return "0x00";
                  }
                  uint256 temp = value;
                  uint256 length = 0;
                  while (temp != 0) {
                      length++;
                      temp >>= 8;
                  }
                  return toHexString(value, length);
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
               */
              function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                  bytes memory buffer = new bytes(2 * length + 2);
                  buffer[0] = "0";
                  buffer[1] = "x";
                  for (uint256 i = 2 * length + 1; i > 1; --i) {
                      buffer[i] = _HEX_SYMBOLS[value & 0xf];
                      value >>= 4;
                  }
                  require(value == 0, "Strings: hex length insufficient");
                  return string(buffer);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/MerkleProof.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev These functions deal with verification of Merkle Trees proofs.
           *
           * The proofs can be generated using the JavaScript library
           * https://github.com/miguelmota/merkletreejs[merkletreejs].
           * Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
           *
           * See `test/utils/cryptography/MerkleProof.test.js` for some examples.
           *
           * WARNING: You should avoid using leaf values that are 64 bytes long prior to
           * hashing, or use a hash function other than keccak256 for hashing leaves.
           * This is because the concatenation of a sorted pair of internal nodes in
           * the merkle tree could be reinterpreted as a leaf value.
           */
          library MerkleProofUpgradeable {
              /**
               * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
               * defined by `root`. For this, a `proof` must be provided, containing
               * sibling hashes on the branch from the leaf to the root of the tree. Each
               * pair of leaves and each pair of pre-images are assumed to be sorted.
               */
              function verify(
                  bytes32[] memory proof,
                  bytes32 root,
                  bytes32 leaf
              ) internal pure returns (bool) {
                  return processProof(proof, leaf) == root;
              }
              /**
               * @dev Returns the rebuilt hash obtained by traversing a Merkle tree up
               * from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
               * hash matches the root of the tree. When processing the proof, the pairs
               * of leafs & pre-images are assumed to be sorted.
               *
               * _Available since v4.4._
               */
              function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {
                  bytes32 computedHash = leaf;
                  for (uint256 i = 0; i < proof.length; i++) {
                      bytes32 proofElement = proof[i];
                      if (computedHash <= proofElement) {
                          // Hash(current computed hash + current element of the proof)
                          computedHash = _efficientHash(computedHash, proofElement);
                      } else {
                          // Hash(current element of the proof + current computed hash)
                          computedHash = _efficientHash(proofElement, computedHash);
                      }
                  }
                  return computedHash;
              }
              function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {
                  assembly {
                      mstore(0x00, a)
                      mstore(0x20, b)
                      value := keccak256(0x00, 0x40)
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
          pragma solidity ^0.8.0;
          import "./IERC165Upgradeable.sol";
          import "../../proxy/utils/Initializable.sol";
          /**
           * @dev Implementation of the {IERC165} interface.
           *
           * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
           * for the additional interface id that will be supported. For example:
           *
           * ```solidity
           * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
           *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
           * }
           * ```
           *
           * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
           */
          abstract contract ERC165Upgradeable is Initializable, IERC165Upgradeable {
              function __ERC165_init() internal onlyInitializing {
              }
              function __ERC165_init_unchained() internal onlyInitializing {
              }
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IERC165Upgradeable).interfaceId;
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC165 standard, as defined in the
           * https://eips.ethereum.org/EIPS/eip-165[EIP].
           *
           * Implementers can declare support of contract interfaces, which can then be
           * queried by others ({ERC165Checker}).
           *
           * For an implementation, see {ERC165}.
           */
          interface IERC165Upgradeable {
              /**
               * @dev Returns true if this contract implements the interface defined by
               * `interfaceId`. See the corresponding
               * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
               * to learn more about how these ids are created.
               *
               * This function call must use less than 30 000 gas.
               */
              function supportsInterface(bytes4 interfaceId) external view returns (bool);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          /**
           ________   _____   ____    ______      ____
          /\\_____  \\ /\\  __`\\/\\  _`\\ /\\  _  \\    /\\  _`\\
          \\/____//'/'\\ \\ \\/\\ \\ \\ \\L\\ \\ \\ \\L\\ \\   \\ \\ \\/\\ \\  _ __   ___   _____     ____
               //'/'  \\ \\ \\ \\ \\ \\ ,  /\\ \\  __ \\   \\ \\ \\ \\ \\/\\`'__\\/ __`\\/\\ '__`\\  /',__\\
              //'/'___ \\ \\ \\_\\ \\ \\ \\\\ \\\\ \\ \\/\\ \\   \\ \\ \\_\\ \\ \\ \\//\\ \\L\\ \\ \\ \\L\\ \\/\\__, `\\
              /\\_______\\\\ \\_____\\ \\_\\ \\_\\ \\_\\ \\_\\   \\ \\____/\\ \\_\\\\ \\____/\\ \\ ,__/\\/\\____/
              \\/_______/ \\/_____/\\/_/\\/ /\\/_/\\/_/    \\/___/  \\/_/ \\/___/  \\ \\ \\/  \\/___/
                                                                           \\ \\_\\
                                                                            \\/_/
           */
          import {ERC721AUpgradeable} from "erc721a-upgradeable/ERC721AUpgradeable.sol";
          import {IERC721AUpgradeable} from "erc721a-upgradeable/IERC721AUpgradeable.sol";
          import {IERC2981Upgradeable, IERC165Upgradeable} from "@openzeppelin/contracts-upgradeable/interfaces/IERC2981Upgradeable.sol";
          import {AccessControlUpgradeable} from "@openzeppelin/contracts-upgradeable/access/AccessControlUpgradeable.sol";
          import {ReentrancyGuardUpgradeable} from "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
          import {MerkleProofUpgradeable} from "@openzeppelin/contracts-upgradeable/utils/cryptography/MerkleProofUpgradeable.sol";
          import {UUPSUpgradeable} from "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
          import {IZoraFeeManager} from "./interfaces/IZoraFeeManager.sol";
          import {IMetadataRenderer} from "./interfaces/IMetadataRenderer.sol";
          import {IOperatorFilterRegistry} from "./interfaces/IOperatorFilterRegistry.sol";
          import {IERC721Drop} from "./interfaces/IERC721Drop.sol";
          import {IOwnable} from "./interfaces/IOwnable.sol";
          import {IFactoryUpgradeGate} from "./interfaces/IFactoryUpgradeGate.sol";
          import {OwnableSkeleton} from "./utils/OwnableSkeleton.sol";
          import {FundsReceiver} from "./utils/FundsReceiver.sol";
          import {Version} from "./utils/Version.sol";
          import {ERC721DropStorageV1} from "./storage/ERC721DropStorageV1.sol";
          /**
           * @notice ZORA NFT Base contract for Drops and Editions
           *
           * @dev For drops: assumes 1. linear mint order, 2. max number of mints needs to be less than max_uint64
           *       (if you have more than 18 quintillion linear mints you should probably not be using this contract)
           * @author [email protected]
           *
           */
          contract ERC721Drop is
              ERC721AUpgradeable,
              UUPSUpgradeable,
              IERC2981Upgradeable,
              ReentrancyGuardUpgradeable,
              AccessControlUpgradeable,
              IERC721Drop,
              OwnableSkeleton,
              FundsReceiver,
              Version(9),
              ERC721DropStorageV1
          {
              /// @dev This is the max mint batch size for the optimized ERC721A mint contract
              uint256 internal immutable MAX_MINT_BATCH_SIZE = 8;
              /// @dev Gas limit to send funds
              uint256 internal immutable FUNDS_SEND_GAS_LIMIT = 210_000;
              /// @notice Access control roles
              bytes32 public immutable MINTER_ROLE = keccak256("MINTER");
              bytes32 public immutable SALES_MANAGER_ROLE = keccak256("SALES_MANAGER");
              /// @dev ZORA V3 transfer helper address for auto-approval
              address internal immutable zoraERC721TransferHelper;
              /// @dev Factory upgrade gate
              IFactoryUpgradeGate internal immutable factoryUpgradeGate;
              /// @dev Zora Fee Manager address
              IZoraFeeManager public immutable zoraFeeManager;
              /// @notice Max royalty BPS
              uint16 constant MAX_ROYALTY_BPS = 50_00;
              address immutable marketFilterDAOAddress;
              IOperatorFilterRegistry immutable operatorFilterRegistry =
                  IOperatorFilterRegistry(0x000000000000AAeB6D7670E522A718067333cd4E);
              /// @notice Only allow for users with admin access
              modifier onlyAdmin() {
                  if (!hasRole(DEFAULT_ADMIN_ROLE, _msgSender())) {
                      revert Access_OnlyAdmin();
                  }
                  _;
              }
              /// @notice Only a given role has access or admin
              /// @param role role to check for alongside the admin role
              modifier onlyRoleOrAdmin(bytes32 role) {
                  if (
                      !hasRole(DEFAULT_ADMIN_ROLE, _msgSender()) &&
                      !hasRole(role, _msgSender())
                  ) {
                      revert Access_MissingRoleOrAdmin(role);
                  }
                  _;
              }
              /// @notice Allows user to mint tokens at a quantity
              modifier canMintTokens(uint256 quantity) {
                  if (quantity + _totalMinted() > config.editionSize) {
                      revert Mint_SoldOut();
                  }
                  _;
              }
              function _presaleActive() internal view returns (bool) {
                  return
                      salesConfig.presaleStart <= block.timestamp &&
                      salesConfig.presaleEnd > block.timestamp;
              }
              function _publicSaleActive() internal view returns (bool) {
                  return
                      salesConfig.publicSaleStart <= block.timestamp &&
                      salesConfig.publicSaleEnd > block.timestamp;
              }
              /// @notice Presale active
              modifier onlyPresaleActive() {
                  if (!_presaleActive()) {
                      revert Presale_Inactive();
                  }
                  _;
              }
              /// @notice Public sale active
              modifier onlyPublicSaleActive() {
                  if (!_publicSaleActive()) {
                      revert Sale_Inactive();
                  }
                  _;
              }
              /// @notice Getter for last minted token ID (gets next token id and subtracts 1)
              function _lastMintedTokenId() internal view returns (uint256) {
                  return _currentIndex - 1;
              }
              /// @notice Start token ID for minting (1-100 vs 0-99)
              function _startTokenId() internal pure override returns (uint256) {
                  return 1;
              }
              /// @notice Global constructor – these variables will not change with further proxy deploys
              /// @dev Marked as an initializer to prevent storage being used of base implementation. Can only be init'd by a proxy.
              /// @param _zoraFeeManager Zora Fee Manager
              /// @param _zoraERC721TransferHelper Transfer helper
              constructor(
                  IZoraFeeManager _zoraFeeManager,
                  address _zoraERC721TransferHelper,
                  IFactoryUpgradeGate _factoryUpgradeGate,
                  address _marketFilterDAOAddress
              ) initializer {
                  zoraFeeManager = _zoraFeeManager;
                  zoraERC721TransferHelper = _zoraERC721TransferHelper;
                  factoryUpgradeGate = _factoryUpgradeGate;
                  marketFilterDAOAddress = _marketFilterDAOAddress;
              }
              ///  @dev Create a new drop contract
              ///  @param _contractName Contract name
              ///  @param _contractSymbol Contract symbol
              ///  @param _initialOwner User that owns and can mint the edition, gets royalty and sales payouts and can update the base url if needed.
              ///  @param _fundsRecipient Wallet/user that receives funds from sale
              ///  @param _editionSize Number of editions that can be minted in total. If 0, unlimited editions can be minted.
              ///  @param _royaltyBPS BPS of the royalty set on the contract. Can be 0 for no royalty.
              ///  @param _salesConfig New sales config to set upon init
              ///  @param _metadataRenderer Renderer contract to use
              ///  @param _metadataRendererInit Renderer data initial contract
              function initialize(
                  string memory _contractName,
                  string memory _contractSymbol,
                  address _initialOwner,
                  address payable _fundsRecipient,
                  uint64 _editionSize,
                  uint16 _royaltyBPS,
                  SalesConfiguration memory _salesConfig,
                  IMetadataRenderer _metadataRenderer,
                  bytes memory _metadataRendererInit
              ) public initializer {
                  // Setup ERC721A
                  __ERC721A_init(_contractName, _contractSymbol);
                  // Setup access control
                  __AccessControl_init();
                  // Setup re-entracy guard
                  __ReentrancyGuard_init();
                  // Setup the owner role
                  _setupRole(DEFAULT_ADMIN_ROLE, _initialOwner);
                  // Set ownership to original sender of contract call
                  _setOwner(_initialOwner);
                  if (config.royaltyBPS > MAX_ROYALTY_BPS) {
                      revert Setup_RoyaltyPercentageTooHigh(MAX_ROYALTY_BPS);
                  }
                  // Update salesConfig
                  salesConfig = _salesConfig;
                  // Setup config variables
                  config.editionSize = _editionSize;
                  config.metadataRenderer = _metadataRenderer;
                  config.royaltyBPS = _royaltyBPS;
                  config.fundsRecipient = _fundsRecipient;
                  _metadataRenderer.initializeWithData(_metadataRendererInit);
              }
              /// @dev Getter for admin role associated with the contract to handle metadata
              /// @return boolean if address is admin
              function isAdmin(address user) external view returns (bool) {
                  return hasRole(DEFAULT_ADMIN_ROLE, user);
              }
              /// @notice Connects this contract to the factory upgrade gate
              /// @param newImplementation proposed new upgrade implementation
              /// @dev Only can be called by admin
              function _authorizeUpgrade(address newImplementation)
                  internal
                  override
                  onlyAdmin
              {
                  if (
                      !factoryUpgradeGate.isValidUpgradePath({
                          _newImpl: newImplementation,
                          _currentImpl: _getImplementation()
                      })
                  ) {
                      revert Admin_InvalidUpgradeAddress(newImplementation);
                  }
              }
              //        ,-.
              //        `-'
              //        /|\\
              //         |             ,----------.
              //        / \\            |ERC721Drop|
              //      Caller           `----+-----'
              //        |       burn()      |
              //        | ------------------>
              //        |                   |
              //        |                   |----.
              //        |                   |    | burn token
              //        |                   |<---'
              //      Caller           ,----+-----.
              //        ,-.            |ERC721Drop|
              //        `-'            `----------'
              //        /|\\
              //         |
              //        / \\
              /// @param tokenId Token ID to burn
              /// @notice User burn function for token id
              function burn(uint256 tokenId) public {
                  _burn(tokenId, true);
              }
              /// @dev Get royalty information for token
              /// @param _salePrice Sale price for the token
              function royaltyInfo(uint256, uint256 _salePrice)
                  external
                  view
                  override
                  returns (address receiver, uint256 royaltyAmount)
              {
                  if (config.fundsRecipient == address(0)) {
                      return (config.fundsRecipient, 0);
                  }
                  return (
                      config.fundsRecipient,
                      (_salePrice * config.royaltyBPS) / 10_000
                  );
              }
              /// @notice Sale details
              /// @return IERC721Drop.SaleDetails sale information details
              function saleDetails()
                  external
                  view
                  returns (IERC721Drop.SaleDetails memory)
              {
                  return
                      IERC721Drop.SaleDetails({
                          publicSaleActive: _publicSaleActive(),
                          presaleActive: _presaleActive(),
                          publicSalePrice: salesConfig.publicSalePrice,
                          publicSaleStart: salesConfig.publicSaleStart,
                          publicSaleEnd: salesConfig.publicSaleEnd,
                          presaleStart: salesConfig.presaleStart,
                          presaleEnd: salesConfig.presaleEnd,
                          presaleMerkleRoot: salesConfig.presaleMerkleRoot,
                          totalMinted: _totalMinted(),
                          maxSupply: config.editionSize,
                          maxSalePurchasePerAddress: salesConfig.maxSalePurchasePerAddress
                      });
              }
              /// @dev Number of NFTs the user has minted per address
              /// @param minter to get counts for
              function mintedPerAddress(address minter)
                  external
                  view
                  override
                  returns (IERC721Drop.AddressMintDetails memory)
              {
                  return
                      IERC721Drop.AddressMintDetails({
                          presaleMints: presaleMintsByAddress[minter],
                          publicMints: _numberMinted(minter) -
                              presaleMintsByAddress[minter],
                          totalMints: _numberMinted(minter)
                      });
              }
              /// @dev Setup auto-approval for Zora v3 access to sell NFT
              ///      Still requires approval for module
              /// @param nftOwner owner of the nft
              /// @param operator operator wishing to transfer/burn/etc the NFTs
              function isApprovedForAll(address nftOwner, address operator)
                  public
                  view
                  override(ERC721AUpgradeable)
                  returns (bool)
              {
                  if (operator == zoraERC721TransferHelper) {
                      return true;
                  }
                  return super.isApprovedForAll(nftOwner, operator);
              }
              /// @dev Gets the zora fee for amount of withdraw
              /// @param amount amount of funds to get fee for
              function zoraFeeForAmount(uint256 amount)
                  public
                  returns (address payable, uint256)
              {
                  (address payable recipient, uint256 bps) = zoraFeeManager
                      .getZORAWithdrawFeesBPS(address(this));
                  return (recipient, (amount * bps) / 10_000);
              }
              /**
               *** ---------------------------------- ***
               ***                                    ***
               ***     PUBLIC MINTING FUNCTIONS       ***
               ***                                    ***
               *** ---------------------------------- ***
               ***/
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                       ,----------.
              //                       / \\                      |ERC721Drop|
              //                     Caller                     `----+-----'
              //                       |          purchase()         |
              //                       | ---------------------------->
              //                       |                             |
              //                       |                             |
              //          ___________________________________________________________
              //          ! ALT  /  drop has no tokens left for caller to mint?      !
              //          !_____/      |                             |               !
              //          !            |    revert Mint_SoldOut()    |               !
              //          !            | <----------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                             |
              //                       |                             |
              //          ___________________________________________________________
              //          ! ALT  /  public sale isn't active?        |               !
              //          !_____/      |                             |               !
              //          !            |    revert Sale_Inactive()   |               !
              //          !            | <----------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                             |
              //                       |                             |
              //          ___________________________________________________________
              //          ! ALT  /  inadequate funds sent?           |               !
              //          !_____/      |                             |               !
              //          !            | revert Purchase_WrongPrice()|               !
              //          !            | <----------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                             |
              //                       |                             |----.
              //                       |                             |    | mint tokens
              //                       |                             |<---'
              //                       |                             |
              //                       |                             |----.
              //                       |                             |    | emit IERC721Drop.Sale()
              //                       |                             |<---'
              //                       |                             |
              //                       | return first minted token ID|
              //                       | <----------------------------
              //                     Caller                     ,----+-----.
              //                       ,-.                      |ERC721Drop|
              //                       `-'                      `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /**
                @dev This allows the user to purchase a edition edition
                     at the given price in the contract.
               */
              function purchase(uint256 quantity)
                  external
                  payable
                  nonReentrant
                  canMintTokens(quantity)
                  onlyPublicSaleActive
                  returns (uint256)
              {
                  uint256 salePrice = salesConfig.publicSalePrice;
                  if (msg.value != salePrice * quantity) {
                      revert Purchase_WrongPrice(salePrice * quantity);
                  }
                  // If max purchase per address == 0 there is no limit.
                  // Any other number, the per address mint limit is that.
                  if (
                      salesConfig.maxSalePurchasePerAddress != 0 &&
                      _numberMinted(_msgSender()) +
                          quantity -
                          presaleMintsByAddress[_msgSender()] >
                      salesConfig.maxSalePurchasePerAddress
                  ) {
                      revert Purchase_TooManyForAddress();
                  }
                  _mintNFTs(_msgSender(), quantity);
                  uint256 firstMintedTokenId = _lastMintedTokenId() - quantity;
                  emit IERC721Drop.Sale({
                      to: _msgSender(),
                      quantity: quantity,
                      pricePerToken: salePrice,
                      firstPurchasedTokenId: firstMintedTokenId
                  });
                  return firstMintedTokenId;
              }
              /// @notice Function to mint NFTs
              /// @dev (important: Does not enforce max supply limit, enforce that limit earlier)
              /// @dev This batches in size of 8 as per recommended by ERC721A creators
              /// @param to address to mint NFTs to
              /// @param quantity number of NFTs to mint
              function _mintNFTs(address to, uint256 quantity) internal {
                  do {
                      uint256 toMint = quantity > MAX_MINT_BATCH_SIZE
                          ? MAX_MINT_BATCH_SIZE
                          : quantity;
                      _mint({to: to, quantity: toMint});
                      quantity -= toMint;
                  } while (quantity > 0);
              }
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                             ,----------.
              //                       / \\                            |ERC721Drop|
              //                     Caller                           `----+-----'
              //                       |         purchasePresale()         |
              //                       | ---------------------------------->
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  drop has no tokens left for caller to mint?            !
              //          !_____/      |                                   |               !
              //          !            |       revert Mint_SoldOut()       |               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  presale sale isn't active?             |               !
              //          !_____/      |                                   |               !
              //          !            |     revert Presale_Inactive()     |               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  merkle proof unapproved for caller?    |               !
              //          !_____/      |                                   |               !
              //          !            | revert Presale_MerkleNotApproved()|               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  inadequate funds sent?                 |               !
              //          !_____/      |                                   |               !
              //          !            |    revert Purchase_WrongPrice()   |               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |----.
              //                       |                                   |    | mint tokens
              //                       |                                   |<---'
              //                       |                                   |
              //                       |                                   |----.
              //                       |                                   |    | emit IERC721Drop.Sale()
              //                       |                                   |<---'
              //                       |                                   |
              //                       |    return first minted token ID   |
              //                       | <----------------------------------
              //                     Caller                           ,----+-----.
              //                       ,-.                            |ERC721Drop|
              //                       `-'                            `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /// @notice Merkle-tree based presale purchase function
              /// @param quantity quantity to purchase
              /// @param maxQuantity max quantity that can be purchased via merkle proof #
              /// @param pricePerToken price that each token is purchased at
              /// @param merkleProof proof for presale mint
              function purchasePresale(
                  uint256 quantity,
                  uint256 maxQuantity,
                  uint256 pricePerToken,
                  bytes32[] calldata merkleProof
              )
                  external
                  payable
                  nonReentrant
                  canMintTokens(quantity)
                  onlyPresaleActive
                  returns (uint256)
              {
                  if (
                      !MerkleProofUpgradeable.verify(
                          merkleProof,
                          salesConfig.presaleMerkleRoot,
                          keccak256(
                              // address, uint256, uint256
                              abi.encode(_msgSender(), maxQuantity, pricePerToken)
                          )
                      )
                  ) {
                      revert Presale_MerkleNotApproved();
                  }
                  if (msg.value != pricePerToken * quantity) {
                      revert Purchase_WrongPrice(pricePerToken * quantity);
                  }
                  presaleMintsByAddress[_msgSender()] += quantity;
                  if (presaleMintsByAddress[_msgSender()] > maxQuantity) {
                      revert Presale_TooManyForAddress();
                  }
                  _mintNFTs(_msgSender(), quantity);
                  uint256 firstMintedTokenId = _lastMintedTokenId() - quantity;
                  emit IERC721Drop.Sale({
                      to: _msgSender(),
                      quantity: quantity,
                      pricePerToken: pricePerToken,
                      firstPurchasedTokenId: firstMintedTokenId
                  });
                  return firstMintedTokenId;
              }
              /**
               *** ---------------------------------- ***
               ***                                    ***
               ***     ADMIN OPERATOR FILTERING       ***
               ***                                    ***
               *** ---------------------------------- ***
               ***/
              /// @notice Proxy to update market filter settings in the main registry contracts
              /// @notice Requires admin permissions
              /// @param args Calldata args to pass to the registry
              function updateMarketFilterSettings(bytes calldata args)
                  external
                  onlyAdmin
                  returns (bytes memory)
              {
                  (bool success, bytes memory ret) = address(operatorFilterRegistry).call(
                      args
                  );
                  if (!success) {
                      revert RemoteOperatorFilterRegistryCallFailed();
                  }
                  return ret;
              }
              /// @notice Manage subscription to the DAO for marketplace filtering based off royalty payouts.
              /// @param enable Enable filtering to non-royalty payout marketplaces
              function manageMarketFilterDAOSubscription(bool enable) external onlyAdmin {
                  address self = address(this);
                  if (marketFilterDAOAddress == address(0x0)) {
                      revert MarketFilterDAOAddressNotSupportedForChain();
                  }
                  if (!operatorFilterRegistry.isRegistered(self) && enable) {
                      operatorFilterRegistry.registerAndSubscribe(self, marketFilterDAOAddress);
                  } else if (enable) {
                      operatorFilterRegistry.subscribe(self, marketFilterDAOAddress);
                  } else {
                      operatorFilterRegistry.unsubscribe(self, false);
                      operatorFilterRegistry.unregister(self);
                  }
              }
              /// @notice Hook to filter operators (no-op if no filters are registered)
              /// @dev Part of ERC721A token hooks
              /// @param from Transfer from user
              /// @param to Transfer to user
              /// @param startTokenId Token ID to start with
              /// @param quantity Quantity of token being transferred
              function _beforeTokenTransfers(
                  address from,
                  address to,
                  uint256 startTokenId,
                  uint256 quantity
              ) internal virtual override {
                  if (
                      from != msg.sender &&
                      address(operatorFilterRegistry).code.length > 0
                  ) {
                      if (
                          !operatorFilterRegistry.isOperatorAllowed(
                              address(this),
                              msg.sender
                          )
                      ) {
                          revert OperatorNotAllowed(msg.sender);
                      }
                  }
              }
              /**
               *** ---------------------------------- ***
               ***                                    ***
               ***     ADMIN MINTING FUNCTIONS        ***
               ***                                    ***
               *** ---------------------------------- ***
               ***/
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                             ,----------.
              //                       / \\                            |ERC721Drop|
              //                     Caller                           `----+-----'
              //                       |            adminMint()            |
              //                       | ---------------------------------->
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  caller is not admin or minter role?    |               !
              //          !_____/      |                                   |               !
              //          !            | revert Access_MissingRoleOrAdmin()|               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  drop has no tokens left for caller to mint?            !
              //          !_____/      |                                   |               !
              //          !            |       revert Mint_SoldOut()       |               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |----.
              //                       |                                   |    | mint tokens
              //                       |                                   |<---'
              //                       |                                   |
              //                       |    return last minted token ID    |
              //                       | <----------------------------------
              //                     Caller                           ,----+-----.
              //                       ,-.                            |ERC721Drop|
              //                       `-'                            `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /// @notice Mint admin
              /// @param recipient recipient to mint to
              /// @param quantity quantity to mint
              function adminMint(address recipient, uint256 quantity)
                  external
                  onlyRoleOrAdmin(MINTER_ROLE)
                  canMintTokens(quantity)
                  returns (uint256)
              {
                  _mintNFTs(recipient, quantity);
                  return _lastMintedTokenId();
              }
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                             ,----------.
              //                       / \\                            |ERC721Drop|
              //                     Caller                           `----+-----'
              //                       |         adminMintAirdrop()        |
              //                       | ---------------------------------->
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  caller is not admin or minter role?    |               !
              //          !_____/      |                                   |               !
              //          !            | revert Access_MissingRoleOrAdmin()|               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  drop has no tokens left for recipients to mint?        !
              //          !_____/      |                                   |               !
              //          !            |       revert Mint_SoldOut()       |               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |
              //                       |                    _____________________________________
              //                       |                    ! LOOP  /  for all recipients        !
              //                       |                    !______/       |                     !
              //                       |                    !              |----.                !
              //                       |                    !              |    | mint tokens    !
              //                       |                    !              |<---'                !
              //                       |                    !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |    return last minted token ID    |
              //                       | <----------------------------------
              //                     Caller                           ,----+-----.
              //                       ,-.                            |ERC721Drop|
              //                       `-'                            `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /// @dev This mints multiple editions to the given list of addresses.
              /// @param recipients list of addresses to send the newly minted editions to
              function adminMintAirdrop(address[] calldata recipients)
                  external
                  override
                  onlyRoleOrAdmin(MINTER_ROLE)
                  canMintTokens(recipients.length)
                  returns (uint256)
              {
                  uint256 atId = _currentIndex;
                  uint256 startAt = atId;
                  unchecked {
                      for (
                          uint256 endAt = atId + recipients.length;
                          atId < endAt;
                          atId++
                      ) {
                          _mintNFTs(recipients[atId - startAt], 1);
                      }
                  }
                  return _lastMintedTokenId();
              }
              /**
               *** ---------------------------------- ***
               ***                                    ***
               ***  ADMIN CONFIGURATION FUNCTIONS     ***
               ***                                    ***
               *** ---------------------------------- ***
               ***/
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                    ,----------.
              //                       / \\                   |ERC721Drop|
              //                     Caller                  `----+-----'
              //                       |        setOwner()        |
              //                       | ------------------------->
              //                       |                          |
              //                       |                          |
              //          ________________________________________________________
              //          ! ALT  /  caller is not admin?          |               !
              //          !_____/      |                          |               !
              //          !            | revert Access_OnlyAdmin()|               !
              //          !            | <-------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                          |
              //                       |                          |----.
              //                       |                          |    | set owner
              //                       |                          |<---'
              //                     Caller                  ,----+-----.
              //                       ,-.                   |ERC721Drop|
              //                       `-'                   `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /// @dev Set new owner for royalties / opensea
              /// @param newOwner new owner to set
              function setOwner(address newOwner) public onlyAdmin {
                  _setOwner(newOwner);
              }
              /// @notice Set a new metadata renderer
              /// @param newRenderer new renderer address to use
              /// @param setupRenderer data to setup new renderer with
              function setMetadataRenderer(
                  IMetadataRenderer newRenderer,
                  bytes memory setupRenderer
              ) external onlyAdmin {
                  config.metadataRenderer = newRenderer;
                  if (setupRenderer.length > 0) {
                      newRenderer.initializeWithData(setupRenderer);
                  }
                  emit UpdatedMetadataRenderer({
                      sender: _msgSender(),
                      renderer: newRenderer
                  });
              }
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                             ,----------.
              //                       / \\                            |ERC721Drop|
              //                     Caller                           `----+-----'
              //                       |      setSalesConfiguration()      |
              //                       | ---------------------------------->
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  caller is not admin?                   |               !
              //          !_____/      |                                   |               !
              //          !            | revert Access_MissingRoleOrAdmin()|               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |----.
              //                       |                                   |    | set funds recipient
              //                       |                                   |<---'
              //                       |                                   |
              //                       |                                   |----.
              //                       |                                   |    | emit FundsRecipientChanged()
              //                       |                                   |<---'
              //                     Caller                           ,----+-----.
              //                       ,-.                            |ERC721Drop|
              //                       `-'                            `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /// @dev This sets the sales configuration
              // / @param publicSalePrice New public sale price
              function setSaleConfiguration(
                  uint104 publicSalePrice,
                  uint32 maxSalePurchasePerAddress,
                  uint64 publicSaleStart,
                  uint64 publicSaleEnd,
                  uint64 presaleStart,
                  uint64 presaleEnd,
                  bytes32 presaleMerkleRoot
              ) external onlyRoleOrAdmin(SALES_MANAGER_ROLE) {
                  // SalesConfiguration storage newConfig = SalesConfiguration({
                  //     publicSaleStart: publicSaleStart,
                  //     publicSaleEnd: publicSaleEnd,
                  //     presaleStart: presaleStart,
                  //     presaleEnd: presaleEnd,
                  //     publicSalePrice: publicSalePrice,
                  //     maxSalePurchasePerAddress: maxSalePurchasePerAddress,
                  //     presaleMerkleRoot: presaleMerkleRoot
                  // });
                  salesConfig.publicSalePrice = publicSalePrice;
                  salesConfig.maxSalePurchasePerAddress = maxSalePurchasePerAddress;
                  salesConfig.publicSaleStart = publicSaleStart;
                  salesConfig.publicSaleEnd = publicSaleEnd;
                  salesConfig.presaleStart = presaleStart;
                  salesConfig.presaleEnd = presaleEnd;
                  salesConfig.presaleMerkleRoot = presaleMerkleRoot;
                  emit SalesConfigChanged(_msgSender());
              }
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                    ,----------.
              //                       / \\                   |ERC721Drop|
              //                     Caller                  `----+-----'
              //                       |        setOwner()        |
              //                       | ------------------------->
              //                       |                          |
              //                       |                          |
              //          ________________________________________________________
              //          ! ALT  /  caller is not admin or SALES_MANAGER_ROLE?    !
              //          !_____/      |                          |               !
              //          !            | revert Access_OnlyAdmin()|               !
              //          !            | <-------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                          |
              //                       |                          |----.
              //                       |                          |    | set sales configuration
              //                       |                          |<---'
              //                       |                          |
              //                       |                          |----.
              //                       |                          |    | emit SalesConfigChanged()
              //                       |                          |<---'
              //                     Caller                  ,----+-----.
              //                       ,-.                   |ERC721Drop|
              //                       `-'                   `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /// @notice Set a different funds recipient
              /// @param newRecipientAddress new funds recipient address
              function setFundsRecipient(address payable newRecipientAddress)
                  external
                  onlyRoleOrAdmin(SALES_MANAGER_ROLE)
              {
                  // TODO(iain): funds recipient cannot be 0?
                  config.fundsRecipient = newRecipientAddress;
                  emit FundsRecipientChanged(newRecipientAddress, _msgSender());
              }
              //                       ,-.                  ,-.                      ,-.
              //                       `-'                  `-'                      `-'
              //                       /|\\                  /|\\                      /|\\
              //                        |                    |                        |                      ,----------.
              //                       / \\                  / \\                      / \\                     |ERC721Drop|
              //                     Caller            FeeRecipient            FundsRecipient                `----+-----'
              //                       |                    |           withdraw()   |                            |
              //                       | ------------------------------------------------------------------------->
              //                       |                    |                        |                            |
              //                       |                    |                        |                            |
              //          ________________________________________________________________________________________________________
              //          ! ALT  /  caller is not admin or manager?                  |                            |               !
              //          !_____/      |                    |                        |                            |               !
              //          !            |                    revert Access_WithdrawNotAllowed()                    |               !
              //          !            | <-------------------------------------------------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                    |                        |                            |
              //                       |                    |                   send fee amount                   |
              //                       |                    | <----------------------------------------------------
              //                       |                    |                        |                            |
              //                       |                    |                        |                            |
              //                       |                    |                        |             ____________________________________________________________
              //                       |                    |                        |             ! ALT  /  send unsuccesful?                                 !
              //                       |                    |                        |             !_____/        |                                            !
              //                       |                    |                        |             !              |----.                                       !
              //                       |                    |                        |             !              |    | revert Withdraw_FundsSendFailure()    !
              //                       |                    |                        |             !              |<---'                                       !
              //                       |                    |                        |             !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                    |                        |             !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                    |                        |                            |
              //                       |                    |                        | send remaining funds amount|
              //                       |                    |                        | <---------------------------
              //                       |                    |                        |                            |
              //                       |                    |                        |                            |
              //                       |                    |                        |             ____________________________________________________________
              //                       |                    |                        |             ! ALT  /  send unsuccesful?                                 !
              //                       |                    |                        |             !_____/        |                                            !
              //                       |                    |                        |             !              |----.                                       !
              //                       |                    |                        |             !              |    | revert Withdraw_FundsSendFailure()    !
              //                       |                    |                        |             !              |<---'                                       !
              //                       |                    |                        |             !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                    |                        |             !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                     Caller            FeeRecipient            FundsRecipient                ,----+-----.
              //                       ,-.                  ,-.                      ,-.                     |ERC721Drop|
              //                       `-'                  `-'                      `-'                     `----------'
              //                       /|\\                  /|\\                      /|\\
              //                        |                    |                        |
              //                       / \\                  / \\                      / \\
              /// @notice This withdraws ETH from the contract to the contract owner.
              function withdraw() external nonReentrant {
                  address sender = _msgSender();
                  // Get fee amount
                  uint256 funds = address(this).balance;
                  (address payable feeRecipient, uint256 zoraFee) = zoraFeeForAmount(
                      funds
                  );
                  // Check if withdraw is allowed for sender
                  if (
                      !hasRole(DEFAULT_ADMIN_ROLE, sender) &&
                      !hasRole(SALES_MANAGER_ROLE, sender) &&
                      sender != feeRecipient &&
                      sender != config.fundsRecipient
                  ) {
                      revert Access_WithdrawNotAllowed();
                  }
                  // Payout ZORA fee
                  if (zoraFee > 0) {
                      (bool successFee, ) = feeRecipient.call{
                          value: zoraFee,
                          gas: FUNDS_SEND_GAS_LIMIT
                      }("");
                      if (!successFee) {
                          revert Withdraw_FundsSendFailure();
                      }
                      funds -= zoraFee;
                  }
                  // Payout recipient
                  (bool successFunds, ) = config.fundsRecipient.call{
                      value: funds,
                      gas: FUNDS_SEND_GAS_LIMIT
                  }("");
                  if (!successFunds) {
                      revert Withdraw_FundsSendFailure();
                  }
                  // Emit event for indexing
                  emit FundsWithdrawn(
                      _msgSender(),
                      config.fundsRecipient,
                      funds,
                      feeRecipient,
                      zoraFee
                  );
              }
              //                       ,-.
              //                       `-'
              //                       /|\\
              //                        |                             ,----------.
              //                       / \\                            |ERC721Drop|
              //                     Caller                           `----+-----'
              //                       |       finalizeOpenEdition()       |
              //                       | ---------------------------------->
              //                       |                                   |
              //                       |                                   |
              //          _________________________________________________________________
              //          ! ALT  /  caller is not admin or SALES_MANAGER_ROLE?             !
              //          !_____/      |                                   |               !
              //          !            | revert Access_MissingRoleOrAdmin()|               !
              //          !            | <----------------------------------               !
              //          !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //          !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |
              //                       |                    _______________________________________________________________________
              //                       |                    ! ALT  /  drop is not an open edition?                                 !
              //                       |                    !_____/        |                                                       !
              //                       |                    !              |----.                                                  !
              //                       |                    !              |    | revert Admin_UnableToFinalizeNotOpenEdition()    !
              //                       |                    !              |<---'                                                  !
              //                       |                    !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                    !~[noop]~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!
              //                       |                                   |
              //                       |                                   |----.
              //                       |                                   |    | set config edition size
              //                       |                                   |<---'
              //                       |                                   |
              //                       |                                   |----.
              //                       |                                   |    | emit OpenMintFinalized()
              //                       |                                   |<---'
              //                     Caller                           ,----+-----.
              //                       ,-.                            |ERC721Drop|
              //                       `-'                            `----------'
              //                       /|\\
              //                        |
              //                       / \\
              /// @notice Admin function to finalize and open edition sale
              function finalizeOpenEdition()
                  external
                  onlyRoleOrAdmin(SALES_MANAGER_ROLE)
              {
                  if (config.editionSize != type(uint64).max) {
                      revert Admin_UnableToFinalizeNotOpenEdition();
                  }
                  config.editionSize = uint64(_totalMinted());
                  emit OpenMintFinalized(_msgSender(), config.editionSize);
              }
              /**
               *** ---------------------------------- ***
               ***                                    ***
               ***      GENERAL GETTER FUNCTIONS      ***
               ***                                    ***
               *** ---------------------------------- ***
               ***/
              /// @notice Simple override for owner interface.
              /// @return user owner address
              function owner()
                  public
                  view
                  override(OwnableSkeleton, IERC721Drop)
                  returns (address)
              {
                  return super.owner();
              }
              /// @notice Contract URI Getter, proxies to metadataRenderer
              /// @return Contract URI
              function contractURI() external view returns (string memory) {
                  return config.metadataRenderer.contractURI();
              }
              /// @notice Getter for metadataRenderer contract
              function metadataRenderer() external view returns (IMetadataRenderer) {
                  return IMetadataRenderer(config.metadataRenderer);
              }
              /// @notice Token URI Getter, proxies to metadataRenderer
              /// @param tokenId id of token to get URI for
              /// @return Token URI
              function tokenURI(uint256 tokenId)
                  public
                  view
                  override
                  returns (string memory)
              {
                  if (!_exists(tokenId)) {
                      revert IERC721AUpgradeable.URIQueryForNonexistentToken();
                  }
                  return config.metadataRenderer.tokenURI(tokenId);
              }
              /// @notice ERC165 supports interface
              /// @param interfaceId interface id to check if supported
              function supportsInterface(bytes4 interfaceId)
                  public
                  view
                  override(
                      IERC165Upgradeable,
                      ERC721AUpgradeable,
                      AccessControlUpgradeable
                  )
                  returns (bool)
              {
                  return
                      super.supportsInterface(interfaceId) ||
                      type(IOwnable).interfaceId == interfaceId ||
                      type(IERC2981Upgradeable).interfaceId == interfaceId ||
                      type(IERC721Drop).interfaceId == interfaceId;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          import {IMetadataRenderer} from "../interfaces/IMetadataRenderer.sol";
          /**
           ________   _____   ____    ______      ____
          /\\_____  \\ /\\  __`\\/\\  _`\\ /\\  _  \\    /\\  _`\\
          \\/____//'/'\\ \\ \\/\\ \\ \\ \\L\\ \\ \\ \\L\\ \\   \\ \\ \\/\\ \\  _ __   ___   _____     ____
               //'/'  \\ \\ \\ \\ \\ \\ ,  /\\ \\  __ \\   \\ \\ \\ \\ \\/\\`'__\\/ __`\\/\\ '__`\\  /',__\\
              //'/'___ \\ \\ \\_\\ \\ \\ \\\\ \\\\ \\ \\/\\ \\   \\ \\ \\_\\ \\ \\ \\//\\ \\L\\ \\ \\ \\L\\ \\/\\__, `\\
              /\\_______\\\\ \\_____\\ \\_\\ \\_\\ \\_\\ \\_\\   \\ \\____/\\ \\_\\\\ \\____/\\ \\ ,__/\\/\\____/
              \\/_______/ \\/_____/\\/_/\\/ /\\/_/\\/_/    \\/___/  \\/_/ \\/___/  \\ \\ \\/  \\/___/
                                                                           \\ \\_\\
                                                                            \\/_/
          */
          /// @notice Interface for ZORA Drops contract
          interface IERC721Drop {
              // Access errors
              /// @notice Only admin can access this function
              error Access_OnlyAdmin();
              /// @notice Missing the given role or admin access
              error Access_MissingRoleOrAdmin(bytes32 role);
              /// @notice Withdraw is not allowed by this user
              error Access_WithdrawNotAllowed();
              /// @notice Cannot withdraw funds due to ETH send failure.
              error Withdraw_FundsSendFailure();
              /// @notice Thrown when the operator for the contract is not allowed
              /// @dev Used when strict enforcement of marketplaces for creator royalties is desired.
              error OperatorNotAllowed(address operator);
              /// @notice Thrown when there is no active market filter DAO address supported for the current chain
              /// @dev Used for enabling and disabling filter for the given chain.
              error MarketFilterDAOAddressNotSupportedForChain();
              /// @notice Used when the operator filter registry external call fails
              /// @dev Used for bubbling error up to clients. 
              error RemoteOperatorFilterRegistryCallFailed();
              // Sale/Purchase errors
              /// @notice Sale is inactive
              error Sale_Inactive();
              /// @notice Presale is inactive
              error Presale_Inactive();
              /// @notice Presale merkle root is invalid
              error Presale_MerkleNotApproved();
              /// @notice Wrong price for purchase
              error Purchase_WrongPrice(uint256 correctPrice);
              /// @notice NFT sold out
              error Mint_SoldOut();
              /// @notice Too many purchase for address
              error Purchase_TooManyForAddress();
              /// @notice Too many presale for address
              error Presale_TooManyForAddress();
              // Admin errors
              /// @notice Royalty percentage too high
              error Setup_RoyaltyPercentageTooHigh(uint16 maxRoyaltyBPS);
              /// @notice Invalid admin upgrade address
              error Admin_InvalidUpgradeAddress(address proposedAddress);
              /// @notice Unable to finalize an edition not marked as open (size set to uint64_max_value)
              error Admin_UnableToFinalizeNotOpenEdition();
              /// @notice Event emitted for each sale
              /// @param to address sale was made to
              /// @param quantity quantity of the minted nfts
              /// @param pricePerToken price for each token
              /// @param firstPurchasedTokenId first purchased token ID (to get range add to quantity for max)
              event Sale(
                  address indexed to,
                  uint256 indexed quantity,
                  uint256 indexed pricePerToken,
                  uint256 firstPurchasedTokenId
              );
              /// @notice Sales configuration has been changed
              /// @dev To access new sales configuration, use getter function.
              /// @param changedBy Changed by user
              event SalesConfigChanged(address indexed changedBy);
              /// @notice Event emitted when the funds recipient is changed
              /// @param newAddress new address for the funds recipient
              /// @param changedBy address that the recipient is changed by
              event FundsRecipientChanged(
                  address indexed newAddress,
                  address indexed changedBy
              );
              /// @notice Event emitted when the funds are withdrawn from the minting contract
              /// @param withdrawnBy address that issued the withdraw
              /// @param withdrawnTo address that the funds were withdrawn to
              /// @param amount amount that was withdrawn
              /// @param feeRecipient user getting withdraw fee (if any)
              /// @param feeAmount amount of the fee getting sent (if any)
              event FundsWithdrawn(
                  address indexed withdrawnBy,
                  address indexed withdrawnTo,
                  uint256 amount,
                  address feeRecipient,
                  uint256 feeAmount
              );
              /// @notice Event emitted when an open mint is finalized and further minting is closed forever on the contract.
              /// @param sender address sending close mint
              /// @param numberOfMints number of mints the contract is finalized at
              event OpenMintFinalized(address indexed sender, uint256 numberOfMints);
              /// @notice Event emitted when metadata renderer is updated.
              /// @param sender address of the updater
              /// @param renderer new metadata renderer address
              event UpdatedMetadataRenderer(address sender, IMetadataRenderer renderer);
              /// @notice General configuration for NFT Minting and bookkeeping
              struct Configuration {
                  /// @dev Metadata renderer (uint160)
                  IMetadataRenderer metadataRenderer;
                  /// @dev Total size of edition that can be minted (uint160+64 = 224)
                  uint64 editionSize;
                  /// @dev Royalty amount in bps (uint224+16 = 240)
                  uint16 royaltyBPS;
                  /// @dev Funds recipient for sale (new slot, uint160)
                  address payable fundsRecipient;
              }
              /// @notice Sales states and configuration
              /// @dev Uses 3 storage slots
              struct SalesConfiguration {
                  /// @dev Public sale price (max ether value > 1000 ether with this value)
                  uint104 publicSalePrice;
                  /// @notice Purchase mint limit per address (if set to 0 === unlimited mints)
                  /// @dev Max purchase number per txn (90+32 = 122)
                  uint32 maxSalePurchasePerAddress;
                  /// @dev uint64 type allows for dates into 292 billion years
                  /// @notice Public sale start timestamp (136+64 = 186)
                  uint64 publicSaleStart;
                  /// @notice Public sale end timestamp (186+64 = 250)
                  uint64 publicSaleEnd;
                  /// @notice Presale start timestamp
                  /// @dev new storage slot
                  uint64 presaleStart;
                  /// @notice Presale end timestamp
                  uint64 presaleEnd;
                  /// @notice Presale merkle root
                  bytes32 presaleMerkleRoot;
              }
              /// @notice Return value for sales details to use with front-ends
              struct SaleDetails {
                  // Synthesized status variables for sale and presale
                  bool publicSaleActive;
                  bool presaleActive;
                  // Price for public sale
                  uint256 publicSalePrice;
                  // Timed sale actions for public sale
                  uint64 publicSaleStart;
                  uint64 publicSaleEnd;
                  // Timed sale actions for presale
                  uint64 presaleStart;
                  uint64 presaleEnd;
                  // Merkle root (includes address, quantity, and price data for each entry)
                  bytes32 presaleMerkleRoot;
                  // Limit public sale to a specific number of mints per wallet
                  uint256 maxSalePurchasePerAddress;
                  // Information about the rest of the supply
                  // Total that have been minted
                  uint256 totalMinted;
                  // The total supply available
                  uint256 maxSupply;
              }
              /// @notice Return type of specific mint counts and details per address
              struct AddressMintDetails {
                  /// Number of total mints from the given address
                  uint256 totalMints;
                  /// Number of presale mints from the given address
                  uint256 presaleMints;
                  /// Number of public mints from the given address
                  uint256 publicMints;
              }
              /// @notice External purchase function (payable in eth)
              /// @param quantity to purchase
              /// @return first minted token ID
              function purchase(uint256 quantity) external payable returns (uint256);
              /// @notice External purchase presale function (takes a merkle proof and matches to root) (payable in eth)
              /// @param quantity to purchase
              /// @param maxQuantity can purchase (verified by merkle root)
              /// @param pricePerToken price per token allowed (verified by merkle root)
              /// @param merkleProof input for merkle proof leaf verified by merkle root
              /// @return first minted token ID
              function purchasePresale(
                  uint256 quantity,
                  uint256 maxQuantity,
                  uint256 pricePerToken,
                  bytes32[] memory merkleProof
              ) external payable returns (uint256);
              /// @notice Function to return the global sales details for the given drop
              function saleDetails() external view returns (SaleDetails memory);
              /// @notice Function to return the specific sales details for a given address
              /// @param minter address for minter to return mint information for
              function mintedPerAddress(address minter)
                  external
                  view
                  returns (AddressMintDetails memory);
              /// @notice This is the opensea/public owner setting that can be set by the contract admin
              function owner() external view returns (address);
              /// @notice Update the metadata renderer
              /// @param newRenderer new address for renderer
              /// @param setupRenderer data to call to bootstrap data for the new renderer (optional)
              function setMetadataRenderer(
                  IMetadataRenderer newRenderer,
                  bytes memory setupRenderer
              ) external;
              /// @notice This is an admin mint function to mint a quantity to a specific address
              /// @param to address to mint to
              /// @param quantity quantity to mint
              /// @return the id of the first minted NFT
              function adminMint(address to, uint256 quantity) external returns (uint256);
              /// @notice This is an admin mint function to mint a single nft each to a list of addresses
              /// @param to list of addresses to mint an NFT each to
              /// @return the id of the first minted NFT
              function adminMintAirdrop(address[] memory to) external returns (uint256);
              /// @dev Getter for admin role associated with the contract to handle metadata
              /// @return boolean if address is admin
              function isAdmin(address user) external view returns (bool);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          interface IFactoryUpgradeGate {
            function isValidUpgradePath(address _newImpl, address _currentImpl) external returns (bool);
            function registerNewUpgradePath(address _newImpl, address[] calldata _supportedPrevImpls) external;
            function unregisterUpgradePath(address _newImpl, address _prevImpl) external;
          }// SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          interface IMetadataRenderer {
              function tokenURI(uint256) external view returns (string memory);
              function contractURI() external view returns (string memory);
              function initializeWithData(bytes memory initData) external;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          interface IOperatorFilterRegistry {
              function isOperatorAllowed(address registrant, address operator) external view returns (bool);
              function register(address registrant) external;
              function registerAndSubscribe(address registrant, address subscription) external;
              function registerAndCopyEntries(address registrant, address registrantToCopy) external;
              function updateOperator(address registrant, address operator, bool filtered) external;
              function updateOperators(address registrant, address[] calldata operators, bool filtered) external;
              function updateCodeHash(address registrant, bytes32 codehash, bool filtered) external;
              function updateCodeHashes(address registrant, bytes32[] calldata codeHashes, bool filtered) external;
              function subscribe(address registrant, address registrantToSubscribe) external;
              function unsubscribe(address registrant, bool copyExistingEntries) external;
              function subscriptionOf(address addr) external returns (address registrant);
              function subscribers(address registrant) external returns (address[] memory);
              function subscriberAt(address registrant, uint256 index) external returns (address);
              function copyEntriesOf(address registrant, address registrantToCopy) external;
              function isOperatorFiltered(address registrant, address operator) external returns (bool);
              function isCodeHashOfFiltered(address registrant, address operatorWithCode) external returns (bool);
              function isCodeHashFiltered(address registrant, bytes32 codeHash) external returns (bool);
              function filteredOperators(address addr) external returns (address[] memory);
              function filteredCodeHashes(address addr) external returns (bytes32[] memory);
              function filteredOperatorAt(address registrant, uint256 index) external returns (address);
              function filteredCodeHashAt(address registrant, uint256 index) external returns (bytes32);
              function isRegistered(address addr) external returns (bool);
              function codeHashOf(address addr) external returns (bytes32);
              function unregister(address registrant) external;
          }// SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * This ownership interface matches OZ's ownable interface.
           *
           */
          interface IOwnable {
              error ONLY_OWNER();
              error ONLY_PENDING_OWNER();
              event OwnershipTransferred(
                  address indexed previousOwner,
                  address indexed newOwner
              );
              event OwnerPending(
                  address indexed previousOwner,
                  address indexed potentialNewOwner
              );
              event OwnerCanceled(
                  address indexed previousOwner,
                  address indexed potentialNewOwner
              );
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() external view returns (address);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          interface IZoraFeeManager {
              function getZORAWithdrawFeesBPS(address sender) external returns (address payable, uint256);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          import {IERC721Drop} from "../interfaces/IERC721Drop.sol";
          contract ERC721DropStorageV1 {
              /// @notice Configuration for NFT minting contract storage
              IERC721Drop.Configuration public config;
              /// @notice Sales configuration
              IERC721Drop.SalesConfiguration public salesConfig;
              /// @dev Mapping for presale mint counts by address to allow public mint limit
              mapping(address => uint256) public presaleMintsByAddress;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          /**
           * @notice This allows this contract to receive native currency funds from other contracts
           * Uses event logging for UI reasons.
           */
          contract FundsReceiver {
              event FundsReceived(address indexed source, uint256 amount);
              receive() external payable {
                  emit FundsReceived(msg.sender, msg.value);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          import {IOwnable} from "../interfaces/IOwnable.sol";
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * This ownership interface matches OZ's ownable interface.
           */
          contract OwnableSkeleton is IOwnable {
              address private _owner;
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() public view virtual returns (address) {
                  return _owner;
              }
              function _setOwner(address newAddress) internal {
                  emit OwnershipTransferred(_owner, newAddress);
                  _owner = newAddress;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.10;
          contract Version {
            uint32 private immutable __version;
            /// @notice The version of the contract
            /// @return The version ID of this contract implementation
            function contractVersion() external view returns (uint32) {
                return __version;
            }
            constructor(uint32 version) {
              __version = version;
            }
          }

          File 5 of 5: OperatorFilterRegistry
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
          pragma solidity ^0.8.0;
          import "../utils/Context.sol";
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * By default, the owner account will be the one that deploys the contract. This
           * can later be changed with {transferOwnership}.
           *
           * This module is used through inheritance. It will make available the modifier
           * `onlyOwner`, which can be applied to your functions to restrict their use to
           * the owner.
           */
          abstract contract Ownable is Context {
              address private _owner;
              event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
              /**
               * @dev Initializes the contract setting the deployer as the initial owner.
               */
              constructor() {
                  _transferOwnership(_msgSender());
              }
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                  _checkOwner();
                  _;
              }
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() public view virtual returns (address) {
                  return _owner;
              }
              /**
               * @dev Throws if the sender is not the owner.
               */
              function _checkOwner() internal view virtual {
                  require(owner() == _msgSender(), "Ownable: caller is not the owner");
              }
              /**
               * @dev Leaves the contract without owner. It will not be possible to call
               * `onlyOwner` functions anymore. Can only be called by the current owner.
               *
               * NOTE: Renouncing ownership will leave the contract without an owner,
               * thereby removing any functionality that is only available to the owner.
               */
              function renounceOwnership() public virtual onlyOwner {
                  _transferOwnership(address(0));
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Can only be called by the current owner.
               */
              function transferOwnership(address newOwner) public virtual onlyOwner {
                  require(newOwner != address(0), "Ownable: new owner is the zero address");
                  _transferOwnership(newOwner);
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Internal function without access restriction.
               */
              function _transferOwnership(address newOwner) internal virtual {
                  address oldOwner = _owner;
                  _owner = newOwner;
                  emit OwnershipTransferred(oldOwner, newOwner);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract Context {
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (utils/structs/EnumerableSet.sol)
          // This file was procedurally generated from scripts/generate/templates/EnumerableSet.js.
          pragma solidity ^0.8.0;
          /**
           * @dev Library for managing
           * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
           * types.
           *
           * Sets have the following properties:
           *
           * - Elements are added, removed, and checked for existence in constant time
           * (O(1)).
           * - Elements are enumerated in O(n). No guarantees are made on the ordering.
           *
           * ```
           * contract Example {
           *     // Add the library methods
           *     using EnumerableSet for EnumerableSet.AddressSet;
           *
           *     // Declare a set state variable
           *     EnumerableSet.AddressSet private mySet;
           * }
           * ```
           *
           * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
           * and `uint256` (`UintSet`) are supported.
           *
           * [WARNING]
           * ====
           * Trying to delete such a structure from storage will likely result in data corruption, rendering the structure
           * unusable.
           * See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.
           *
           * In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an
           * array of EnumerableSet.
           * ====
           */
          library EnumerableSet {
              // To implement this library for multiple types with as little code
              // repetition as possible, we write it in terms of a generic Set type with
              // bytes32 values.
              // The Set implementation uses private functions, and user-facing
              // implementations (such as AddressSet) are just wrappers around the
              // underlying Set.
              // This means that we can only create new EnumerableSets for types that fit
              // in bytes32.
              struct Set {
                  // Storage of set values
                  bytes32[] _values;
                  // Position of the value in the `values` array, plus 1 because index 0
                  // means a value is not in the set.
                  mapping(bytes32 => uint256) _indexes;
              }
              /**
               * @dev Add a value to a set. O(1).
               *
               * Returns true if the value was added to the set, that is if it was not
               * already present.
               */
              function _add(Set storage set, bytes32 value) private returns (bool) {
                  if (!_contains(set, value)) {
                      set._values.push(value);
                      // The value is stored at length-1, but we add 1 to all indexes
                      // and use 0 as a sentinel value
                      set._indexes[value] = set._values.length;
                      return true;
                  } else {
                      return false;
                  }
              }
              /**
               * @dev Removes a value from a set. O(1).
               *
               * Returns true if the value was removed from the set, that is if it was
               * present.
               */
              function _remove(Set storage set, bytes32 value) private returns (bool) {
                  // We read and store the value's index to prevent multiple reads from the same storage slot
                  uint256 valueIndex = set._indexes[value];
                  if (valueIndex != 0) {
                      // Equivalent to contains(set, value)
                      // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                      // the array, and then remove the last element (sometimes called as 'swap and pop').
                      // This modifies the order of the array, as noted in {at}.
                      uint256 toDeleteIndex = valueIndex - 1;
                      uint256 lastIndex = set._values.length - 1;
                      if (lastIndex != toDeleteIndex) {
                          bytes32 lastValue = set._values[lastIndex];
                          // Move the last value to the index where the value to delete is
                          set._values[toDeleteIndex] = lastValue;
                          // Update the index for the moved value
                          set._indexes[lastValue] = valueIndex; // Replace lastValue's index to valueIndex
                      }
                      // Delete the slot where the moved value was stored
                      set._values.pop();
                      // Delete the index for the deleted slot
                      delete set._indexes[value];
                      return true;
                  } else {
                      return false;
                  }
              }
              /**
               * @dev Returns true if the value is in the set. O(1).
               */
              function _contains(Set storage set, bytes32 value) private view returns (bool) {
                  return set._indexes[value] != 0;
              }
              /**
               * @dev Returns the number of values on the set. O(1).
               */
              function _length(Set storage set) private view returns (uint256) {
                  return set._values.length;
              }
              /**
               * @dev Returns the value stored at position `index` in the set. O(1).
               *
               * Note that there are no guarantees on the ordering of values inside the
               * array, and it may change when more values are added or removed.
               *
               * Requirements:
               *
               * - `index` must be strictly less than {length}.
               */
              function _at(Set storage set, uint256 index) private view returns (bytes32) {
                  return set._values[index];
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function _values(Set storage set) private view returns (bytes32[] memory) {
                  return set._values;
              }
              // Bytes32Set
              struct Bytes32Set {
                  Set _inner;
              }
              /**
               * @dev Add a value to a set. O(1).
               *
               * Returns true if the value was added to the set, that is if it was not
               * already present.
               */
              function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
                  return _add(set._inner, value);
              }
              /**
               * @dev Removes a value from a set. O(1).
               *
               * Returns true if the value was removed from the set, that is if it was
               * present.
               */
              function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
                  return _remove(set._inner, value);
              }
              /**
               * @dev Returns true if the value is in the set. O(1).
               */
              function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
                  return _contains(set._inner, value);
              }
              /**
               * @dev Returns the number of values in the set. O(1).
               */
              function length(Bytes32Set storage set) internal view returns (uint256) {
                  return _length(set._inner);
              }
              /**
               * @dev Returns the value stored at position `index` in the set. O(1).
               *
               * Note that there are no guarantees on the ordering of values inside the
               * array, and it may change when more values are added or removed.
               *
               * Requirements:
               *
               * - `index` must be strictly less than {length}.
               */
              function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
                  return _at(set._inner, index);
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
                  bytes32[] memory store = _values(set._inner);
                  bytes32[] memory result;
                  /// @solidity memory-safe-assembly
                  assembly {
                      result := store
                  }
                  return result;
              }
              // AddressSet
              struct AddressSet {
                  Set _inner;
              }
              /**
               * @dev Add a value to a set. O(1).
               *
               * Returns true if the value was added to the set, that is if it was not
               * already present.
               */
              function add(AddressSet storage set, address value) internal returns (bool) {
                  return _add(set._inner, bytes32(uint256(uint160(value))));
              }
              /**
               * @dev Removes a value from a set. O(1).
               *
               * Returns true if the value was removed from the set, that is if it was
               * present.
               */
              function remove(AddressSet storage set, address value) internal returns (bool) {
                  return _remove(set._inner, bytes32(uint256(uint160(value))));
              }
              /**
               * @dev Returns true if the value is in the set. O(1).
               */
              function contains(AddressSet storage set, address value) internal view returns (bool) {
                  return _contains(set._inner, bytes32(uint256(uint160(value))));
              }
              /**
               * @dev Returns the number of values in the set. O(1).
               */
              function length(AddressSet storage set) internal view returns (uint256) {
                  return _length(set._inner);
              }
              /**
               * @dev Returns the value stored at position `index` in the set. O(1).
               *
               * Note that there are no guarantees on the ordering of values inside the
               * array, and it may change when more values are added or removed.
               *
               * Requirements:
               *
               * - `index` must be strictly less than {length}.
               */
              function at(AddressSet storage set, uint256 index) internal view returns (address) {
                  return address(uint160(uint256(_at(set._inner, index))));
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function values(AddressSet storage set) internal view returns (address[] memory) {
                  bytes32[] memory store = _values(set._inner);
                  address[] memory result;
                  /// @solidity memory-safe-assembly
                  assembly {
                      result := store
                  }
                  return result;
              }
              // UintSet
              struct UintSet {
                  Set _inner;
              }
              /**
               * @dev Add a value to a set. O(1).
               *
               * Returns true if the value was added to the set, that is if it was not
               * already present.
               */
              function add(UintSet storage set, uint256 value) internal returns (bool) {
                  return _add(set._inner, bytes32(value));
              }
              /**
               * @dev Removes a value from a set. O(1).
               *
               * Returns true if the value was removed from the set, that is if it was
               * present.
               */
              function remove(UintSet storage set, uint256 value) internal returns (bool) {
                  return _remove(set._inner, bytes32(value));
              }
              /**
               * @dev Returns true if the value is in the set. O(1).
               */
              function contains(UintSet storage set, uint256 value) internal view returns (bool) {
                  return _contains(set._inner, bytes32(value));
              }
              /**
               * @dev Returns the number of values in the set. O(1).
               */
              function length(UintSet storage set) internal view returns (uint256) {
                  return _length(set._inner);
              }
              /**
               * @dev Returns the value stored at position `index` in the set. O(1).
               *
               * Note that there are no guarantees on the ordering of values inside the
               * array, and it may change when more values are added or removed.
               *
               * Requirements:
               *
               * - `index` must be strictly less than {length}.
               */
              function at(UintSet storage set, uint256 index) internal view returns (uint256) {
                  return uint256(_at(set._inner, index));
              }
              /**
               * @dev Return the entire set in an array
               *
               * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
               * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
               * this function has an unbounded cost, and using it as part of a state-changing function may render the function
               * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
               */
              function values(UintSet storage set) internal view returns (uint256[] memory) {
                  bytes32[] memory store = _values(set._inner);
                  uint256[] memory result;
                  /// @solidity memory-safe-assembly
                  assembly {
                      result := store
                  }
                  return result;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.13;
          import {EnumerableSet} from "openzeppelin-contracts/utils/structs/EnumerableSet.sol";
          interface IOperatorFilterRegistry {
              function isOperatorAllowed(address registrant, address operator) external returns (bool);
              function register(address registrant) external;
              function registerAndSubscribe(address registrant, address subscription) external;
              function registerAndCopyEntries(address registrant, address registrantToCopy) external;
              function updateOperator(address registrant, address operator, bool filtered) external;
              function updateOperators(address registrant, address[] calldata operators, bool filtered) external;
              function updateCodeHash(address registrant, bytes32 codehash, bool filtered) external;
              function updateCodeHashes(address registrant, bytes32[] calldata codeHashes, bool filtered) external;
              function subscribe(address registrant, address registrantToSubscribe) external;
              function unsubscribe(address registrant, bool copyExistingEntries) external;
              function subscriptionOf(address addr) external returns (address registrant);
              function subscribers(address registrant) external returns (address[] memory);
              function subscriberAt(address registrant, uint256 index) external returns (address);
              function copyEntriesOf(address registrant, address registrantToCopy) external;
              function isOperatorFiltered(address registrant, address operator) external returns (bool);
              function isCodeHashOfFiltered(address registrant, address operatorWithCode) external returns (bool);
              function isCodeHashFiltered(address registrant, bytes32 codeHash) external returns (bool);
              function filteredOperators(address addr) external returns (address[] memory);
              function filteredCodeHashes(address addr) external returns (bytes32[] memory);
              function filteredOperatorAt(address registrant, uint256 index) external returns (address);
              function filteredCodeHashAt(address registrant, uint256 index) external returns (bytes32);
              function isRegistered(address addr) external returns (bool);
              function codeHashOf(address addr) external returns (bytes32);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.13;
          import {IOperatorFilterRegistry} from "./IOperatorFilterRegistry.sol";
          import {Ownable} from "openzeppelin-contracts/access/Ownable.sol";
          import {EnumerableSet} from "openzeppelin-contracts/utils/structs/EnumerableSet.sol";
          import {OperatorFilterRegistryErrorsAndEvents} from "./OperatorFilterRegistryErrorsAndEvents.sol";
          /**
           * @title  OperatorFilterRegistry
           * @notice Borrows heavily from the QQL BlacklistOperatorFilter contract:
           *         https://github.com/qql-art/contracts/blob/main/contracts/BlacklistOperatorFilter.sol
           * @notice This contracts allows tokens or token owners to register specific addresses or codeHashes that may be
           * *       restricted according to the isOperatorAllowed function.
           */
          contract OperatorFilterRegistry is IOperatorFilterRegistry, OperatorFilterRegistryErrorsAndEvents {
              using EnumerableSet for EnumerableSet.AddressSet;
              using EnumerableSet for EnumerableSet.Bytes32Set;
              /// @dev initialized accounts have a nonzero codehash (see https://eips.ethereum.org/EIPS/eip-1052)
              /// Note that this will also be a smart contract's codehash when making calls from its constructor.
              bytes32 constant EOA_CODEHASH = keccak256("");
              mapping(address => EnumerableSet.AddressSet) private _filteredOperators;
              mapping(address => EnumerableSet.Bytes32Set) private _filteredCodeHashes;
              mapping(address => address) private _registrations;
              mapping(address => EnumerableSet.AddressSet) private _subscribers;
              /**
               * @notice restricts method caller to the address or EIP-173 "owner()"
               */
              modifier onlyAddressOrOwner(address addr) {
                  if (msg.sender != addr) {
                      try Ownable(addr).owner() returns (address owner) {
                          if (msg.sender != owner) {
                              revert OnlyAddressOrOwner();
                          }
                      } catch (bytes memory reason) {
                          if (reason.length == 0) {
                              revert NotOwnable();
                          } else {
                              /// @solidity memory-safe-assembly
                              assembly {
                                  revert(add(32, reason), mload(reason))
                              }
                          }
                      }
                  }
                  _;
              }
              /**
               * @notice Returns true if operator is not filtered for a given token, either by address or codeHash. Also returns
               *         true if supplied registrant address is not registered.
               */
              function isOperatorAllowed(address registrant, address operator) external view returns (bool) {
                  address registration = _registrations[registrant];
                  if (registration != address(0)) {
                      EnumerableSet.AddressSet storage filteredOperatorsRef;
                      EnumerableSet.Bytes32Set storage filteredCodeHashesRef;
                      filteredOperatorsRef = _filteredOperators[registration];
                      filteredCodeHashesRef = _filteredCodeHashes[registration];
                      if (filteredOperatorsRef.contains(operator)) {
                          revert AddressFiltered(operator);
                      }
                      if (operator.code.length > 0) {
                          bytes32 codeHash = operator.codehash;
                          if (filteredCodeHashesRef.contains(codeHash)) {
                              revert CodeHashFiltered(operator, codeHash);
                          }
                      }
                  }
                  return true;
              }
              //////////////////
              // AUTH METHODS //
              //////////////////
              /**
               * @notice Registers an address with the registry. May be called by address itself or by EIP-173 owner.
               */
              function register(address registrant) external onlyAddressOrOwner(registrant) {
                  if (_registrations[registrant] != address(0)) {
                      revert AlreadyRegistered();
                  }
                  _registrations[registrant] = registrant;
                  emit RegistrationUpdated(registrant, true);
              }
              /**
               * @notice Unregisters an address with the registry and removes its subscription. May be called by address itself or by EIP-173 owner.
               *         Note that this does not remove any filtered addresses or codeHashes.
               *         Also note that any subscriptions to this registrant will still be active and follow the existing filtered addresses and codehashes.
               */
              function unregister(address registrant) external onlyAddressOrOwner(registrant) {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      _subscribers[registration].remove(registrant);
                      emit SubscriptionUpdated(registrant, registration, false);
                  }
                  _registrations[registrant] = address(0);
                  emit RegistrationUpdated(registrant, false);
              }
              /**
               * @notice Registers an address with the registry and "subscribes" to another address's filtered operators and codeHashes.
               */
              function registerAndSubscribe(address registrant, address subscription) external onlyAddressOrOwner(registrant) {
                  address registration = _registrations[registrant];
                  if (registration != address(0)) {
                      revert AlreadyRegistered();
                  }
                  if (registrant == subscription) {
                      revert CannotSubscribeToSelf();
                  }
                  address subscriptionRegistration = _registrations[subscription];
                  if (subscriptionRegistration == address(0)) {
                      revert NotRegistered(subscription);
                  }
                  if (subscriptionRegistration != subscription) {
                      revert CannotSubscribeToRegistrantWithSubscription(subscription);
                  }
                  _registrations[registrant] = subscription;
                  _subscribers[subscription].add(registrant);
                  emit RegistrationUpdated(registrant, true);
                  emit SubscriptionUpdated(registrant, subscription, true);
              }
              /**
               * @notice Registers an address with the registry and copies the filtered operators and codeHashes from another
               *         address without subscribing.
               */
              function registerAndCopyEntries(address registrant, address registrantToCopy)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  if (registrantToCopy == registrant) {
                      revert CannotCopyFromSelf();
                  }
                  address registration = _registrations[registrant];
                  if (registration != address(0)) {
                      revert AlreadyRegistered();
                  }
                  address registrantRegistration = _registrations[registrantToCopy];
                  if (registrantRegistration == address(0)) {
                      revert NotRegistered(registrantToCopy);
                  }
                  _registrations[registrant] = registrant;
                  emit RegistrationUpdated(registrant, true);
                  _copyEntries(registrant, registrantToCopy);
              }
              /**
               * @notice Update an operator address for a registered address - when filtered is true, the operator is filtered.
               */
              function updateOperator(address registrant, address operator, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.AddressSet storage filteredOperatorsRef = _filteredOperators[registrant];
                  if (!filtered) {
                      bool removed = filteredOperatorsRef.remove(operator);
                      if (!removed) {
                          revert AddressNotFiltered(operator);
                      }
                  } else {
                      bool added = filteredOperatorsRef.add(operator);
                      if (!added) {
                          revert AddressAlreadyFiltered(operator);
                      }
                  }
                  emit OperatorUpdated(registrant, operator, filtered);
              }
              /**
               * @notice Update a codeHash for a registered address - when filtered is true, the codeHash is filtered.
               */
              function updateCodeHash(address registrant, bytes32 codeHash, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  if (codeHash == EOA_CODEHASH) {
                      revert CannotFilterEOAs();
                  }
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.Bytes32Set storage filteredCodeHashesRef = _filteredCodeHashes[registrant];
                  if (!filtered) {
                      bool removed = filteredCodeHashesRef.remove(codeHash);
                      if (!removed) {
                          revert CodeHashNotFiltered(codeHash);
                      }
                  } else {
                      bool added = filteredCodeHashesRef.add(codeHash);
                      if (!added) {
                          revert CodeHashAlreadyFiltered(codeHash);
                      }
                  }
                  emit CodeHashUpdated(registrant, codeHash, filtered);
              }
              /**
               * @notice Update multiple operators for a registered address - when filtered is true, the operators will be filtered. Reverts on duplicates.
               */
              function updateOperators(address registrant, address[] calldata operators, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.AddressSet storage filteredOperatorsRef = _filteredOperators[registrant];
                  uint256 operatorsLength = operators.length;
                  unchecked {
                      if (!filtered) {
                          for (uint256 i = 0; i < operatorsLength; ++i) {
                              address operator = operators[i];
                              bool removed = filteredOperatorsRef.remove(operator);
                              if (!removed) {
                                  revert AddressNotFiltered(operator);
                              }
                          }
                      } else {
                          for (uint256 i = 0; i < operatorsLength; ++i) {
                              address operator = operators[i];
                              bool added = filteredOperatorsRef.add(operator);
                              if (!added) {
                                  revert AddressAlreadyFiltered(operator);
                              }
                          }
                      }
                  }
                  emit OperatorsUpdated(registrant, operators, filtered);
              }
              /**
               * @notice Update multiple codeHashes for a registered address - when filtered is true, the codeHashes will be filtered. Reverts on duplicates.
               */
              function updateCodeHashes(address registrant, bytes32[] calldata codeHashes, bool filtered)
                  external
                  onlyAddressOrOwner(registrant)
              {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  EnumerableSet.Bytes32Set storage filteredCodeHashesRef = _filteredCodeHashes[registrant];
                  uint256 codeHashesLength = codeHashes.length;
                  unchecked {
                      if (!filtered) {
                          for (uint256 i = 0; i < codeHashesLength; ++i) {
                              bytes32 codeHash = codeHashes[i];
                              bool removed = filteredCodeHashesRef.remove(codeHash);
                              if (!removed) {
                                  revert CodeHashNotFiltered(codeHash);
                              }
                          }
                      } else {
                          for (uint256 i = 0; i < codeHashesLength; ++i) {
                              bytes32 codeHash = codeHashes[i];
                              if (codeHash == EOA_CODEHASH) {
                                  revert CannotFilterEOAs();
                              }
                              bool added = filteredCodeHashesRef.add(codeHash);
                              if (!added) {
                                  revert CodeHashAlreadyFiltered(codeHash);
                              }
                          }
                      }
                  }
                  emit CodeHashesUpdated(registrant, codeHashes, filtered);
              }
              /**
               * @notice Subscribe an address to another registrant's filtered operators and codeHashes. Will remove previous
               *         subscription if present.
               *         Note that accounts with subscriptions may go on to subscribe to other accounts - in this case,
               *         subscriptions will not be forwarded. Instead the former subscription's existing entries will still be
               *         used.
               */
              function subscribe(address registrant, address newSubscription) external onlyAddressOrOwner(registrant) {
                  if (registrant == newSubscription) {
                      revert CannotSubscribeToSelf();
                  }
                  if (newSubscription == address(0)) {
                      revert CannotSubscribeToZeroAddress();
                  }
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration == newSubscription) {
                      revert AlreadySubscribed(newSubscription);
                  }
                  address newSubscriptionRegistration = _registrations[newSubscription];
                  if (newSubscriptionRegistration == address(0)) {
                      revert NotRegistered(newSubscription);
                  }
                  if (newSubscriptionRegistration != newSubscription) {
                      revert CannotSubscribeToRegistrantWithSubscription(newSubscription);
                  }
                  if (registration != registrant) {
                      _subscribers[registration].remove(registrant);
                      emit SubscriptionUpdated(registrant, registration, false);
                  }
                  _registrations[registrant] = newSubscription;
                  _subscribers[newSubscription].add(registrant);
                  emit SubscriptionUpdated(registrant, newSubscription, true);
              }
              /**
               * @notice Unsubscribe an address from its current subscribed registrant, and optionally copy its filtered operators and codeHashes.
               */
              function unsubscribe(address registrant, bool copyExistingEntries) external onlyAddressOrOwner(registrant) {
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration == registrant) {
                      revert NotSubscribed();
                  }
                  _subscribers[registration].remove(registrant);
                  _registrations[registrant] = registrant;
                  emit SubscriptionUpdated(registrant, registration, false);
                  if (copyExistingEntries) {
                      _copyEntries(registrant, registration);
                  }
              }
              /**
               * @notice Copy filtered operators and codeHashes from a different registrantToCopy to addr.
               */
              function copyEntriesOf(address registrant, address registrantToCopy) external onlyAddressOrOwner(registrant) {
                  if (registrant == registrantToCopy) {
                      revert CannotCopyFromSelf();
                  }
                  address registration = _registrations[registrant];
                  if (registration == address(0)) {
                      revert NotRegistered(registrant);
                  }
                  if (registration != registrant) {
                      revert CannotUpdateWhileSubscribed(registration);
                  }
                  address registrantRegistration = _registrations[registrantToCopy];
                  if (registrantRegistration == address(0)) {
                      revert NotRegistered(registrantToCopy);
                  }
                  _copyEntries(registrant, registrantToCopy);
              }
              /// @dev helper to copy entries from registrantToCopy to registrant and emit events
              function _copyEntries(address registrant, address registrantToCopy) private {
                  EnumerableSet.AddressSet storage filteredOperatorsRef = _filteredOperators[registrantToCopy];
                  EnumerableSet.Bytes32Set storage filteredCodeHashesRef = _filteredCodeHashes[registrantToCopy];
                  uint256 filteredOperatorsLength = filteredOperatorsRef.length();
                  uint256 filteredCodeHashesLength = filteredCodeHashesRef.length();
                  unchecked {
                      for (uint256 i = 0; i < filteredOperatorsLength; ++i) {
                          address operator = filteredOperatorsRef.at(i);
                          bool added = _filteredOperators[registrant].add(operator);
                          if (added) {
                              emit OperatorUpdated(registrant, operator, true);
                          }
                      }
                      for (uint256 i = 0; i < filteredCodeHashesLength; ++i) {
                          bytes32 codehash = filteredCodeHashesRef.at(i);
                          bool added = _filteredCodeHashes[registrant].add(codehash);
                          if (added) {
                              emit CodeHashUpdated(registrant, codehash, true);
                          }
                      }
                  }
              }
              //////////////////
              // VIEW METHODS //
              //////////////////
              /**
               * @notice Get the subscription address of a given registrant, if any.
               */
              function subscriptionOf(address registrant) external view returns (address subscription) {
                  subscription = _registrations[registrant];
                  if (subscription == address(0)) {
                      revert NotRegistered(registrant);
                  } else if (subscription == registrant) {
                      subscription = address(0);
                  }
              }
              /**
               * @notice Get the set of addresses subscribed to a given registrant.
               *         Note that order is not guaranteed as updates are made.
               */
              function subscribers(address registrant) external view returns (address[] memory) {
                  return _subscribers[registrant].values();
              }
              /**
               * @notice Get the subscriber at a given index in the set of addresses subscribed to a given registrant.
               *         Note that order is not guaranteed as updates are made.
               */
              function subscriberAt(address registrant, uint256 index) external view returns (address) {
                  return _subscribers[registrant].at(index);
              }
              /**
               * @notice Returns true if operator is filtered by a given address or its subscription.
               */
              function isOperatorFiltered(address registrant, address operator) external view returns (bool) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredOperators[registration].contains(operator);
                  }
                  return _filteredOperators[registrant].contains(operator);
              }
              /**
               * @notice Returns true if a codeHash is filtered by a given address or its subscription.
               */
              function isCodeHashFiltered(address registrant, bytes32 codeHash) external view returns (bool) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].contains(codeHash);
                  }
                  return _filteredCodeHashes[registrant].contains(codeHash);
              }
              /**
               * @notice Returns true if the hash of an address's code is filtered by a given address or its subscription.
               */
              function isCodeHashOfFiltered(address registrant, address operatorWithCode) external view returns (bool) {
                  bytes32 codeHash = operatorWithCode.codehash;
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].contains(codeHash);
                  }
                  return _filteredCodeHashes[registrant].contains(codeHash);
              }
              /**
               * @notice Returns true if an address has registered
               */
              function isRegistered(address registrant) external view returns (bool) {
                  return _registrations[registrant] != address(0);
              }
              /**
               * @notice Returns a list of filtered operators for a given address or its subscription.
               */
              function filteredOperators(address registrant) external view returns (address[] memory) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredOperators[registration].values();
                  }
                  return _filteredOperators[registrant].values();
              }
              /**
               * @notice Returns the set of filtered codeHashes for a given address or its subscription.
               *         Note that order is not guaranteed as updates are made.
               */
              function filteredCodeHashes(address registrant) external view returns (bytes32[] memory) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].values();
                  }
                  return _filteredCodeHashes[registrant].values();
              }
              /**
               * @notice Returns the filtered operator at the given index of the set of filtered operators for a given address or
               *         its subscription.
               *         Note that order is not guaranteed as updates are made.
               */
              function filteredOperatorAt(address registrant, uint256 index) external view returns (address) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredOperators[registration].at(index);
                  }
                  return _filteredOperators[registrant].at(index);
              }
              /**
               * @notice Returns the filtered codeHash at the given index of the list of filtered codeHashes for a given address or
               *         its subscription.
               *         Note that order is not guaranteed as updates are made.
               */
              function filteredCodeHashAt(address registrant, uint256 index) external view returns (bytes32) {
                  address registration = _registrations[registrant];
                  if (registration != registrant) {
                      return _filteredCodeHashes[registration].at(index);
                  }
                  return _filteredCodeHashes[registrant].at(index);
              }
              /// @dev Convenience method to compute the code hash of an arbitrary contract
              function codeHashOf(address a) external view returns (bytes32) {
                  return a.codehash;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.13;
          contract OperatorFilterRegistryErrorsAndEvents {
              error CannotFilterEOAs();
              error AddressAlreadyFiltered(address operator);
              error AddressNotFiltered(address operator);
              error CodeHashAlreadyFiltered(bytes32 codeHash);
              error CodeHashNotFiltered(bytes32 codeHash);
              error OnlyAddressOrOwner();
              error NotRegistered(address registrant);
              error AlreadyRegistered();
              error AlreadySubscribed(address subscription);
              error NotSubscribed();
              error CannotUpdateWhileSubscribed(address subscription);
              error CannotSubscribeToSelf();
              error CannotSubscribeToZeroAddress();
              error NotOwnable();
              error AddressFiltered(address filtered);
              error CodeHashFiltered(address account, bytes32 codeHash);
              error CannotSubscribeToRegistrantWithSubscription(address registrant);
              error CannotCopyFromSelf();
              event RegistrationUpdated(address indexed registrant, bool indexed registered);
              event OperatorUpdated(address indexed registrant, address indexed operator, bool indexed filtered);
              event OperatorsUpdated(address indexed registrant, address[] operators, bool indexed filtered);
              event CodeHashUpdated(address indexed registrant, bytes32 indexed codeHash, bool indexed filtered);
              event CodeHashesUpdated(address indexed registrant, bytes32[] codeHashes, bool indexed filtered);
              event SubscriptionUpdated(address indexed registrant, address indexed subscription, bool indexed subscribed);
          }