ETH Price: $2,968.08 (+1.70%)

Transaction Decoder

Block:
17730479 at Jul-19-2023 11:21:59 PM +UTC
Transaction Fee:
0.00198540357721808 ETH $5.89
Gas Used:
108,208 Gas / 18.34802951 Gwei

Account State Difference:

  Address   Before After State Difference Code
0x6BAdB08A...5738f2F20
0.062043969463646942 Eth
Nonce: 35
0.060058565886428862 Eth
Nonce: 36
0.00198540357721808
(Flashbots: Builder)
0.047764803066582448 Eth0.047873011066582448 Eth0.000108208

Execution Trace

ETH 0.03 ReservoirV6_0_0.execute( executionInfos= )
  • ETH 0.03 LooksRareModule.acceptETHListing( takerBid=[{name:isOrderAsk, type:bool, order:1, indexed:false, value:false, valueString:False}, {name:taker, type:address, order:2, indexed:false, value:0x385df8CBC196f5f780367F3cDC96aF072a916F7E, valueString:0x385df8CBC196f5f780367F3cDC96aF072a916F7E}, {name:price, type:uint256, order:3, indexed:false, value:30000000000000000, valueString:30000000000000000}, {name:tokenId, type:uint256, order:4, indexed:false, value:29778219029302101805476646757504608306510148187096141407585334785147894501332, valueString:29778219029302101805476646757504608306510148187096141407585334785147894501332}, {name:minPercentageToAsk, type:uint256, order:5, indexed:false, value:9800, valueString:9800}, {name:params, type:bytes, order:6, indexed:false, value:0x, valueString:0x}], makerAsk=[{name:isOrderAsk, type:bool, order:1, indexed:false, value:true, valueString:True}, {name:signer, type:address, order:2, indexed:false, value:0x33C3959a8917d9759147c1FEe705BEDBdE702991, valueString:0x33C3959a8917d9759147c1FEe705BEDBdE702991}, {name:collection, type:address, order:3, indexed:false, value:0x57f1887a8BF19b14fC0dF6Fd9B2acc9Af147eA85, valueString:0x57f1887a8BF19b14fC0dF6Fd9B2acc9Af147eA85}, {name:price, type:uint256, order:4, indexed:false, value:30000000000000000, valueString:30000000000000000}, {name:tokenId, type:uint256, order:5, indexed:false, value:29778219029302101805476646757504608306510148187096141407585334785147894501332, valueString:29778219029302101805476646757504608306510148187096141407585334785147894501332}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:strategy, type:address, order:7, indexed:false, value:0x579af6FD30BF83a5Ac0D636bc619f98DBdeb930c, valueString:0x579af6FD30BF83a5Ac0D636bc619f98DBdeb930c}, {name:currency, type:address, order:8, indexed:false, value:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, valueString:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2}, {name:nonce, type:uint256, order:9, indexed:false, value:161, valueString:161}, {name:startTime, type:uint256, order:10, indexed:false, value:1675625348, valueString:1675625348}, {name:endTime, type:uint256, order:11, indexed:false, value:1678217334, valueString:1678217334}, {name:minPercentageToAsk, type:uint256, order:12, indexed:false, value:9800, valueString:9800}, {name:params, type:bytes, order:13, indexed:false, value:0x, valueString:0x}, {name:v, type:uint8, order:14, indexed:false, value:27, valueString:27}, {name:r, type:bytes32, order:15, indexed:false, value:06830EB60777B53FE0D4C2BCF8C4EEE8C1AFB207C5B1239B89ACEB59B60CB9A1, valueString:06830EB60777B53FE0D4C2BCF8C4EEE8C1AFB207C5B1239B89ACEB59B60CB9A1}, {name:s, type:bytes32, order:16, indexed:false, value:5C46E88B2881798B8D35B7C6E6533D160C68482529373AB136789F2A802735DA, valueString:5C46E88B2881798B8D35B7C6E6533D160C68482529373AB136789F2A802735DA}], params=[{name:fillTo, type:address, order:1, indexed:false, value:0x6BAdB08AfA48DD2A88637C9E1111d585738f2F20, valueString:0x6BAdB08AfA48DD2A88637C9E1111d585738f2F20}, {name:refundTo, type:address, order:2, indexed:false, value:0x6BAdB08AfA48DD2A88637C9E1111d585738f2F20, valueString:0x6BAdB08AfA48DD2A88637C9E1111d585738f2F20}, {name:revertIfIncomplete, type:bool, order:3, indexed:false, value:true, valueString:True}, {name:amount, type:uint256, order:4, indexed:false, value:30000000000000000, valueString:30000000000000000}], fees= )
    • ETH 0.03 LooksRareExchange.matchAskWithTakerBidUsingETHAndWETH( takerBid=[{name:isOrderAsk, type:bool, order:1, indexed:false, value:false, valueString:False}, {name:taker, type:address, order:2, indexed:false, value:0x385df8CBC196f5f780367F3cDC96aF072a916F7E, valueString:0x385df8CBC196f5f780367F3cDC96aF072a916F7E}, {name:price, type:uint256, order:3, indexed:false, value:30000000000000000, valueString:30000000000000000}, {name:tokenId, type:uint256, order:4, indexed:false, value:29778219029302101805476646757504608306510148187096141407585334785147894501332, valueString:29778219029302101805476646757504608306510148187096141407585334785147894501332}, {name:minPercentageToAsk, type:uint256, order:5, indexed:false, value:9800, valueString:9800}, {name:params, type:bytes, order:6, indexed:false, value:0x, valueString:0x}], makerAsk=[{name:isOrderAsk, type:bool, order:1, indexed:false, value:true, valueString:True}, {name:signer, type:address, order:2, indexed:false, value:0x33C3959a8917d9759147c1FEe705BEDBdE702991, valueString:0x33C3959a8917d9759147c1FEe705BEDBdE702991}, {name:collection, type:address, order:3, indexed:false, value:0x57f1887a8BF19b14fC0dF6Fd9B2acc9Af147eA85, valueString:0x57f1887a8BF19b14fC0dF6Fd9B2acc9Af147eA85}, {name:price, type:uint256, order:4, indexed:false, value:30000000000000000, valueString:30000000000000000}, {name:tokenId, type:uint256, order:5, indexed:false, value:29778219029302101805476646757504608306510148187096141407585334785147894501332, valueString:29778219029302101805476646757504608306510148187096141407585334785147894501332}, {name:amount, type:uint256, order:6, indexed:false, value:1, valueString:1}, {name:strategy, type:address, order:7, indexed:false, value:0x579af6FD30BF83a5Ac0D636bc619f98DBdeb930c, valueString:0x579af6FD30BF83a5Ac0D636bc619f98DBdeb930c}, {name:currency, type:address, order:8, indexed:false, value:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, valueString:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2}, {name:nonce, type:uint256, order:9, indexed:false, value:161, valueString:161}, {name:startTime, type:uint256, order:10, indexed:false, value:1675625348, valueString:1675625348}, {name:endTime, type:uint256, order:11, indexed:false, value:1678217334, valueString:1678217334}, {name:minPercentageToAsk, type:uint256, order:12, indexed:false, value:9800, valueString:9800}, {name:params, type:bytes, order:13, indexed:false, value:0x, valueString:0x}, {name:v, type:uint8, order:14, indexed:false, value:27, valueString:27}, {name:r, type:bytes32, order:15, indexed:false, value:06830EB60777B53FE0D4C2BCF8C4EEE8C1AFB207C5B1239B89ACEB59B60CB9A1, valueString:06830EB60777B53FE0D4C2BCF8C4EEE8C1AFB207C5B1239B89ACEB59B60CB9A1}, {name:s, type:bytes32, order:16, indexed:false, value:5C46E88B2881798B8D35B7C6E6533D160C68482529373AB136789F2A802735DA, valueString:5C46E88B2881798B8D35B7C6E6533D160C68482529373AB136789F2A802735DA}] )
      • ETH 0.03 WETH9.CALL( )
      • Null: 0x000...001.33016061( )
      • CurrencyManager.isCurrencyWhitelisted( currency=0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2 ) => ( False )
        File 1 of 5: ReservoirV6_0_0
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.9;
        import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
        import {Address} from "@openzeppelin/contracts/utils/Address.sol";
        contract ReservoirV6_0_0 is ReentrancyGuard {
            using Address for address;
            // --- Structs ---
            struct ExecutionInfo {
                address module;
                bytes data;
                uint256 value;
            }
            struct AmountCheckInfo {
                address target;
                bytes data;
                uint256 threshold;
            }
            // --- Errors ---
            error UnsuccessfulExecution();
            error UnsuccessfulPayment();
            // --- Modifiers ---
            modifier refundETH() {
                _;
                uint256 leftover = address(this).balance;
                if (leftover > 0) {
                    (bool success, ) = payable(msg.sender).call{value: leftover}("");
                    if (!success) {
                        revert UnsuccessfulPayment();
                    }
                }
            }
            // --- Fallback ---
            receive() external payable {}
            // --- Public ---
            // Trigger a set of executions atomically
            function execute(ExecutionInfo[] calldata executionInfos)
                external
                payable
                nonReentrant
                refundETH
            {
                uint256 length = executionInfos.length;
                for (uint256 i = 0; i < length; ) {
                    _executeInternal(executionInfos[i]);
                    unchecked {
                        ++i;
                    }
                }
            }
            // Trigger a set of executions with amount checking. As opposed to the regular
            // `execute` method, `executeWithAmountCheck` supports stopping the executions
            // once the provided amount check reaches a certain value. This is useful when
            // trying to fill orders with slippage (eg. provide multiple orders and try to
            // fill until a certain balance is reached). In order to be flexible, checking
            // the amount is done generically by calling the `target` contract with `data`.
            // For example, this could be used to check the ERC721 total owned balance (by
            // using `balanceOf(owner)`), the ERC1155 total owned balance per token id (by
            // using `balanceOf(owner, tokenId)`), but also for checking the ERC1155 total
            // owned balance per multiple token ids (by using a custom contract that wraps
            // `balanceOfBatch(owners, tokenIds)`).
            function executeWithAmountCheck(
                ExecutionInfo[] calldata executionInfos,
                AmountCheckInfo calldata amountCheckInfo
            ) external payable nonReentrant refundETH {
                // Cache some data for efficiency
                address target = amountCheckInfo.target;
                bytes calldata data = amountCheckInfo.data;
                uint256 threshold = amountCheckInfo.threshold;
                uint256 length = executionInfos.length;
                for (uint256 i = 0; i < length; ) {
                    // Check the amount and break if it exceeds the threshold
                    uint256 amount = _getAmount(target, data);
                    if (amount >= threshold) {
                        break;
                    }
                    _executeInternal(executionInfos[i]);
                    unchecked {
                        ++i;
                    }
                }
            }
            // --- Internal ---
            function _executeInternal(ExecutionInfo calldata executionInfo) internal {
                address module = executionInfo.module;
                // Ensure the target is a contract
                if (!module.isContract()) {
                    revert UnsuccessfulExecution();
                }
                (bool success, ) = module.call{value: executionInfo.value}(
                    executionInfo.data
                );
                if (!success) {
                    revert UnsuccessfulExecution();
                }
            }
            function _getAmount(address target, bytes calldata data)
                internal
                view
                returns (uint256 amount)
            {
                // Ensure the target is a contract
                if (!target.isContract()) {
                    revert UnsuccessfulExecution();
                }
                (bool success, bytes memory result) = target.staticcall(data);
                if (!success) {
                    revert UnsuccessfulExecution();
                }
                amount = abi.decode(result, (uint256));
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.0 (security/ReentrancyGuard.sol)
        pragma solidity ^0.8.0;
        /**
         * @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 ReentrancyGuard {
            // 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;
            constructor() {
                _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;
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.0 (utils/Address.sol)
        pragma solidity ^0.8.0;
        /**
         * @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
             * ====
             */
            function isContract(address account) internal view returns (bool) {
                // This method relies on extcodesize, which returns 0 for contracts in
                // construction, since the code is only stored at the end of the
                // constructor execution.
                uint256 size;
                assembly {
                    size := extcodesize(account)
                }
                return size > 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);
                    }
                }
            }
        }
        

        File 2 of 5: LooksRareModule
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
        pragma solidity ^0.8.0;
        /**
         * @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 ReentrancyGuard {
            // 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;
            constructor() {
                _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;
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC1155/IERC1155.sol)
        pragma solidity ^0.8.0;
        import "../../utils/introspection/IERC165.sol";
        /**
         * @dev Required interface of an ERC1155 compliant contract, as defined in the
         * https://eips.ethereum.org/EIPS/eip-1155[EIP].
         *
         * _Available since v3.1._
         */
        interface IERC1155 is IERC165 {
            /**
             * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.
             */
            event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);
            /**
             * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all
             * transfers.
             */
            event TransferBatch(
                address indexed operator,
                address indexed from,
                address indexed to,
                uint256[] ids,
                uint256[] values
            );
            /**
             * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to
             * `approved`.
             */
            event ApprovalForAll(address indexed account, address indexed operator, bool approved);
            /**
             * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.
             *
             * If an {URI} event was emitted for `id`, the standard
             * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value
             * returned by {IERC1155MetadataURI-uri}.
             */
            event URI(string value, uint256 indexed id);
            /**
             * @dev Returns the amount of tokens of token type `id` owned by `account`.
             *
             * Requirements:
             *
             * - `account` cannot be the zero address.
             */
            function balanceOf(address account, uint256 id) external view returns (uint256);
            /**
             * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.
             *
             * Requirements:
             *
             * - `accounts` and `ids` must have the same length.
             */
            function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids)
                external
                view
                returns (uint256[] memory);
            /**
             * @dev Grants or revokes permission to `operator` to transfer the caller's tokens, according to `approved`,
             *
             * Emits an {ApprovalForAll} event.
             *
             * Requirements:
             *
             * - `operator` cannot be the caller.
             */
            function setApprovalForAll(address operator, bool approved) external;
            /**
             * @dev Returns true if `operator` is approved to transfer ``account``'s tokens.
             *
             * See {setApprovalForAll}.
             */
            function isApprovedForAll(address account, address operator) external view returns (bool);
            /**
             * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.
             *
             * Emits a {TransferSingle} event.
             *
             * Requirements:
             *
             * - `to` cannot be the zero address.
             * - If the caller is not `from`, it must have been approved to spend ``from``'s tokens via {setApprovalForAll}.
             * - `from` must have a balance of tokens of type `id` of at least `amount`.
             * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
             * acceptance magic value.
             */
            function safeTransferFrom(
                address from,
                address to,
                uint256 id,
                uint256 amount,
                bytes calldata data
            ) external;
            /**
             * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.
             *
             * Emits a {TransferBatch} event.
             *
             * Requirements:
             *
             * - `ids` and `amounts` must have the same length.
             * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
             * acceptance magic value.
             */
            function safeBatchTransferFrom(
                address from,
                address to,
                uint256[] calldata ids,
                uint256[] calldata amounts,
                bytes calldata data
            ) external;
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
        pragma solidity ^0.8.0;
        /**
         * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
         * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
         *
         * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
         * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
         * need to send a transaction, and thus is not required to hold Ether at all.
         */
        interface IERC20Permit {
            /**
             * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
             * given ``owner``'s signed approval.
             *
             * IMPORTANT: The same issues {IERC20-approve} has related to transaction
             * ordering also apply here.
             *
             * Emits an {Approval} event.
             *
             * Requirements:
             *
             * - `spender` cannot be the zero address.
             * - `deadline` must be a timestamp in the future.
             * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
             * over the EIP712-formatted function arguments.
             * - the signature must use ``owner``'s current nonce (see {nonces}).
             *
             * For more information on the signature format, see the
             * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
             * section].
             */
            function permit(
                address owner,
                address spender,
                uint256 value,
                uint256 deadline,
                uint8 v,
                bytes32 r,
                bytes32 s
            ) external;
            /**
             * @dev Returns the current nonce for `owner`. This value must be
             * included whenever a signature is generated for {permit}.
             *
             * Every successful call to {permit} increases ``owner``'s nonce by one. This
             * prevents a signature from being used multiple times.
             */
            function nonces(address owner) external view returns (uint256);
            /**
             * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
             */
            // solhint-disable-next-line func-name-mixedcase
            function DOMAIN_SEPARATOR() external view returns (bytes32);
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
        pragma solidity ^0.8.0;
        /**
         * @dev Interface of the ERC20 standard as defined in the EIP.
         */
        interface IERC20 {
            /**
             * @dev Emitted when `value` tokens are moved from one account (`from`) to
             * another (`to`).
             *
             * Note that `value` may be zero.
             */
            event Transfer(address indexed from, address indexed to, uint256 value);
            /**
             * @dev Emitted when the allowance of a `spender` for an `owner` is set by
             * a call to {approve}. `value` is the new allowance.
             */
            event Approval(address indexed owner, address indexed spender, uint256 value);
            /**
             * @dev Returns the amount of tokens in existence.
             */
            function totalSupply() external view returns (uint256);
            /**
             * @dev Returns the amount of tokens owned by `account`.
             */
            function balanceOf(address account) external view returns (uint256);
            /**
             * @dev Moves `amount` tokens from the caller's account to `to`.
             *
             * Returns a boolean value indicating whether the operation succeeded.
             *
             * Emits a {Transfer} event.
             */
            function transfer(address to, uint256 amount) external returns (bool);
            /**
             * @dev Returns the remaining number of tokens that `spender` will be
             * allowed to spend on behalf of `owner` through {transferFrom}. This is
             * zero by default.
             *
             * This value changes when {approve} or {transferFrom} are called.
             */
            function allowance(address owner, address spender) external view returns (uint256);
            /**
             * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
             *
             * Returns a boolean value indicating whether the operation succeeded.
             *
             * IMPORTANT: Beware that changing an allowance with this method brings the risk
             * that someone may use both the old and the new allowance by unfortunate
             * transaction ordering. One possible solution to mitigate this race
             * condition is to first reduce the spender's allowance to 0 and set the
             * desired value afterwards:
             * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
             *
             * Emits an {Approval} event.
             */
            function approve(address spender, uint256 amount) external returns (bool);
            /**
             * @dev Moves `amount` tokens from `from` to `to` using the
             * allowance mechanism. `amount` is then deducted from the caller's
             * allowance.
             *
             * Returns a boolean value indicating whether the operation succeeded.
             *
             * Emits a {Transfer} event.
             */
            function transferFrom(
                address from,
                address to,
                uint256 amount
            ) external returns (bool);
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)
        pragma solidity ^0.8.0;
        import "../IERC20.sol";
        import "../extensions/draft-IERC20Permit.sol";
        import "../../../utils/Address.sol";
        /**
         * @title SafeERC20
         * @dev Wrappers around ERC20 operations that throw on failure (when the token
         * contract returns false). Tokens that return no value (and instead revert or
         * throw on failure) are also supported, non-reverting calls are assumed to be
         * successful.
         * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
         * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
         */
        library SafeERC20 {
            using Address for address;
            function safeTransfer(
                IERC20 token,
                address to,
                uint256 value
            ) internal {
                _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
            }
            function safeTransferFrom(
                IERC20 token,
                address from,
                address to,
                uint256 value
            ) internal {
                _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
            }
            /**
             * @dev Deprecated. This function has issues similar to the ones found in
             * {IERC20-approve}, and its usage is discouraged.
             *
             * Whenever possible, use {safeIncreaseAllowance} and
             * {safeDecreaseAllowance} instead.
             */
            function safeApprove(
                IERC20 token,
                address spender,
                uint256 value
            ) internal {
                // safeApprove should only be called when setting an initial allowance,
                // or when resetting it to zero. To increase and decrease it, use
                // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                require(
                    (value == 0) || (token.allowance(address(this), spender) == 0),
                    "SafeERC20: approve from non-zero to non-zero allowance"
                );
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
            }
            function safeIncreaseAllowance(
                IERC20 token,
                address spender,
                uint256 value
            ) internal {
                uint256 newAllowance = token.allowance(address(this), spender) + value;
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
            }
            function safeDecreaseAllowance(
                IERC20 token,
                address spender,
                uint256 value
            ) internal {
                unchecked {
                    uint256 oldAllowance = token.allowance(address(this), spender);
                    require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                    uint256 newAllowance = oldAllowance - value;
                    _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                }
            }
            function safePermit(
                IERC20Permit token,
                address owner,
                address spender,
                uint256 value,
                uint256 deadline,
                uint8 v,
                bytes32 r,
                bytes32 s
            ) internal {
                uint256 nonceBefore = token.nonces(owner);
                token.permit(owner, spender, value, deadline, v, r, s);
                uint256 nonceAfter = token.nonces(owner);
                require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
            }
            /**
             * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
             * on the return value: the return value is optional (but if data is returned, it must not be false).
             * @param token The token targeted by the call.
             * @param data The call data (encoded using abi.encode or one of its variants).
             */
            function _callOptionalReturn(IERC20 token, bytes memory data) private {
                // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                // the target address contains contract code and also asserts for success in the low-level call.
                bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                if (returndata.length > 0) {
                    // Return data is optional
                    require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                }
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/IERC721.sol)
        pragma solidity ^0.8.0;
        import "../../utils/introspection/IERC165.sol";
        /**
         * @dev Required interface of an ERC721 compliant contract.
         */
        interface IERC721 is IERC165 {
            /**
             * @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`.
             *
             * 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;
            /**
             * @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 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 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 the account approved for `tokenId` token.
             *
             * Requirements:
             *
             * - `tokenId` must exist.
             */
            function getApproved(uint256 tokenId) external view returns (address operator);
            /**
             * @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);
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
        pragma solidity ^0.8.1;
        /**
         * @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
                        /// @solidity memory-safe-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/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 IERC165 {
            /**
             * @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 ^0.8.9;
        import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
        import {IERC165} from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
        interface ILooksRare {
            struct MakerOrder {
                bool isOrderAsk;
                address signer;
                IERC165 collection;
                uint256 price;
                uint256 tokenId;
                uint256 amount;
                address strategy;
                IERC20 currency;
                uint256 nonce;
                uint256 startTime;
                uint256 endTime;
                uint256 minPercentageToAsk;
                bytes params;
                uint8 v;
                bytes32 r;
                bytes32 s;
            }
            struct TakerOrder {
                bool isOrderAsk;
                address taker;
                uint256 price;
                uint256 tokenId;
                uint256 minPercentageToAsk;
                bytes params;
            }
            function transferSelectorNFT() external view returns (address);
            function matchAskWithTakerBidUsingETHAndWETH(
                TakerOrder calldata takerBid,
                MakerOrder calldata makerAsk
            ) external payable;
            function matchAskWithTakerBid(
                TakerOrder calldata takerBid,
                MakerOrder calldata makerAsk
            ) external payable;
            function matchBidWithTakerAsk(
                TakerOrder calldata takerAsk,
                MakerOrder calldata makerBid
            ) external;
        }
        interface ILooksRareTransferSelectorNFT {
            function TRANSFER_MANAGER_ERC721() external view returns (address);
            function TRANSFER_MANAGER_ERC1155() external view returns (address);
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.9;
        // Adapted from:
        // https://github.com/boringcrypto/BoringSolidity/blob/e74c5b22a61bfbadd645e51a64aa1d33734d577a/contracts/BoringOwnable.sol
        contract TwoStepOwnable {
            // --- Fields ---
            address public owner;
            address public pendingOwner;
            // --- Events ---
            event OwnershipTransferred(
                address indexed previousOwner,
                address indexed newOwner
            );
            // --- Errors ---
            error InvalidParams();
            error Unauthorized();
            // --- Modifiers ---
            modifier onlyOwner() {
                if (msg.sender != owner) {
                    revert Unauthorized();
                }
                _;
            }
            // --- Constructor ---
            constructor(address initialOwner) {
                owner = initialOwner;
                emit OwnershipTransferred(address(0), initialOwner);
            }
            // --- Methods ---
            function transferOwnership(address newOwner) public onlyOwner {
                pendingOwner = newOwner;
            }
            function claimOwnership() public {
                address _pendingOwner = pendingOwner;
                if (msg.sender != _pendingOwner) {
                    revert Unauthorized();
                }
                owner = _pendingOwner;
                pendingOwner = address(0);
                emit OwnershipTransferred(owner, _pendingOwner);
            }
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.9;
        import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
        import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
        import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
        import {TwoStepOwnable} from "../../misc/TwoStepOwnable.sol";
        // Notes:
        // - includes common helpers useful for all modules
        abstract contract BaseModule is TwoStepOwnable, ReentrancyGuard {
            using SafeERC20 for IERC20;
            // --- Events ---
            event CallExecuted(address target, bytes data, uint256 value);
            // --- Errors ---
            error UnsuccessfulCall();
            error UnsuccessfulPayment();
            error WrongParams();
            // --- Constructor ---
            constructor(address owner) TwoStepOwnable(owner) {}
            // --- Owner ---
            // To be able to recover anything that gets stucked by mistake in the module,
            // we allow the owner to perform any arbitrary call. Since the goal is to be
            // stateless, this should only happen in case of mistakes. In addition, this
            // method is also useful for withdrawing any earned trading rewards.
            function makeCalls(
                address[] calldata targets,
                bytes[] calldata data,
                uint256[] calldata values
            ) external payable onlyOwner nonReentrant {
                uint256 length = targets.length;
                for (uint256 i = 0; i < length; ) {
                    _makeCall(targets[i], data[i], values[i]);
                    emit CallExecuted(targets[i], data[i], values[i]);
                    unchecked {
                        ++i;
                    }
                }
            }
            // --- Helpers ---
            function _sendETH(address to, uint256 amount) internal {
                if (amount > 0) {
                    (bool success, ) = payable(to).call{value: amount}("");
                    if (!success) {
                        revert UnsuccessfulPayment();
                    }
                }
            }
            function _sendERC20(
                address to,
                uint256 amount,
                IERC20 token
            ) internal {
                if (amount > 0) {
                    token.safeTransfer(to, amount);
                }
            }
            function _makeCall(
                address target,
                bytes memory data,
                uint256 value
            ) internal {
                (bool success, ) = payable(target).call{value: value}(data);
                if (!success) {
                    revert UnsuccessfulCall();
                }
            }
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.9;
        import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
        import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
        import {IERC721} from "@openzeppelin/contracts/token/ERC721/IERC721.sol";
        import {IERC1155} from "@openzeppelin/contracts/token/ERC1155/IERC1155.sol";
        import {BaseModule} from "../BaseModule.sol";
        // Notes:
        // - includes common helpers useful for all marketplace/exchange modules
        abstract contract BaseExchangeModule is BaseModule {
            using SafeERC20 for IERC20;
            // --- Structs ---
            // Every fill execution has the following parameters:
            // - `fillTo`: the recipient of the received items
            // - `refundTo`: the recipient of any refunds
            // - `revertIfIncomplete`: whether to revert or skip unsuccessful fills
            // The below `ETHListingParams` and `ERC20ListingParams` rely on the
            // off-chain execution encoder to ensure that the orders filled with
            // the passed in listing parameters exactly match (eg. order amounts
            // and payment tokens match).
            struct ETHListingParams {
                address fillTo;
                address refundTo;
                bool revertIfIncomplete;
                // The total amount of ETH to be provided when filling
                uint256 amount;
            }
            struct ERC20ListingParams {
                address fillTo;
                address refundTo;
                bool revertIfIncomplete;
                // The ERC20 payment token for the listings
                IERC20 token;
                // The total amount of `token` to be provided when filling
                uint256 amount;
            }
            struct OfferParams {
                address fillTo;
                address refundTo;
                bool revertIfIncomplete;
            }
            struct Fee {
                address recipient;
                uint256 amount;
            }
            // --- Fields ---
            address public immutable router;
            // --- Errors ---
            error UnsuccessfulFill();
            // --- Constructor ---
            constructor(address routerAddress) {
                router = routerAddress;
            }
            // --- Modifiers ---
            modifier refundETHLeftover(address refundTo) {
                _;
                uint256 leftover = address(this).balance;
                if (leftover > 0) {
                    _sendETH(refundTo, leftover);
                }
            }
            modifier refundERC20Leftover(address refundTo, IERC20 token) {
                _;
                uint256 leftover = token.balanceOf(address(this));
                if (leftover > 0) {
                    token.safeTransfer(refundTo, leftover);
                }
            }
            modifier chargeETHFees(Fee[] calldata fees, uint256 amount) {
                if (fees.length == 0) {
                    _;
                } else {
                    uint256 balanceBefore = address(this).balance;
                    _;
                    uint256 length = fees.length;
                    if (length > 0) {
                        uint256 balanceAfter = address(this).balance;
                        uint256 actualPaid = balanceBefore - balanceAfter;
                        uint256 actualFee;
                        for (uint256 i = 0; i < length; ) {
                            // Adjust the fee to what was actually paid
                            actualFee = (fees[i].amount * actualPaid) / amount;
                            if (actualFee > 0) {
                                _sendETH(fees[i].recipient, actualFee);
                            }
                            unchecked {
                                ++i;
                            }
                        }
                    }
                }
            }
            modifier chargeERC20Fees(
                Fee[] calldata fees,
                IERC20 token,
                uint256 amount
            ) {
                if (fees.length == 0) {
                    _;
                } else {
                    uint256 balanceBefore = token.balanceOf(address(this));
                    _;
                    uint256 length = fees.length;
                    if (length > 0) {
                        uint256 balanceAfter = token.balanceOf(address(this));
                        uint256 actualPaid = balanceBefore - balanceAfter;
                        uint256 actualFee;
                        for (uint256 i = 0; i < length; ) {
                            // Adjust the fee to what was actually paid
                            actualFee = (fees[i].amount * actualPaid) / amount;
                            if (actualFee > 0) {
                                token.safeTransfer(fees[i].recipient, actualFee);
                            }
                            unchecked {
                                ++i;
                            }
                        }
                    }
                }
            }
            // --- Helpers ---
            function _sendAllETH(address to) internal {
                _sendETH(to, address(this).balance);
            }
            function _sendAllERC20(address to, IERC20 token) internal {
                uint256 balance = token.balanceOf(address(this));
                if (balance > 0) {
                    token.safeTransfer(to, balance);
                }
            }
            function _sendAllERC721(
                address to,
                IERC721 token,
                uint256 tokenId
            ) internal {
                if (token.ownerOf(tokenId) == address(this)) {
                    token.safeTransferFrom(address(this), to, tokenId);
                }
            }
            function _sendAllERC1155(
                address to,
                IERC1155 token,
                uint256 tokenId
            ) internal {
                uint256 balance = token.balanceOf(address(this), tokenId);
                if (balance > 0) {
                    token.safeTransferFrom(address(this), to, tokenId, balance, "");
                }
            }
            function _approveERC20IfNeeded(
                IERC20 token,
                address spender,
                uint256 amount
            ) internal {
                uint256 allowance = token.allowance(address(this), spender);
                if (allowance < amount) {
                    token.approve(spender, amount - allowance);
                }
            }
            function _approveERC721IfNeeded(IERC721 token, address operator) internal {
                bool isApproved = token.isApprovedForAll(address(this), operator);
                if (!isApproved) {
                    token.setApprovalForAll(operator, true);
                }
            }
            function _approveERC1155IfNeeded(IERC1155 token, address operator)
                internal
            {
                bool isApproved = token.isApprovedForAll(address(this), operator);
                if (!isApproved) {
                    token.setApprovalForAll(operator, true);
                }
            }
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.9;
        import {IERC1155} from "@openzeppelin/contracts/token/ERC1155/IERC1155.sol";
        import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
        import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
        import {IERC721} from "@openzeppelin/contracts/token/ERC721/IERC721.sol";
        import {IERC165} from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
        import {BaseExchangeModule} from "./BaseExchangeModule.sol";
        import {BaseModule} from "../BaseModule.sol";
        import {ILooksRare} from "../../../interfaces/ILooksRare.sol";
        // Notes:
        // - supports filling listings (both ERC721/ERC1155 but only ETH-denominated)
        // - supports filling offers (both ERC721/ERC1155)
        contract LooksRareModule is BaseExchangeModule {
            using SafeERC20 for IERC20;
            // --- Fields ---
            ILooksRare public constant EXCHANGE =
                ILooksRare(0x59728544B08AB483533076417FbBB2fD0B17CE3a);
            address public constant ERC721_TRANSFER_MANAGER =
                0xf42aa99F011A1fA7CDA90E5E98b277E306BcA83e;
            address public constant ERC1155_TRANSFER_MANAGER =
                0xFED24eC7E22f573c2e08AEF55aA6797Ca2b3A051;
            bytes4 public constant ERC721_INTERFACE = 0x80ac58cd;
            bytes4 public constant ERC1155_INTERFACE = 0xd9b67a26;
            // --- Constructor ---
            constructor(address owner, address router)
                BaseModule(owner)
                BaseExchangeModule(router)
            {}
            // --- Single ETH listing ---
            function acceptETHListing(
                ILooksRare.TakerOrder calldata takerBid,
                ILooksRare.MakerOrder calldata makerAsk,
                ETHListingParams calldata params,
                Fee[] calldata fees
            )
                external
                payable
                nonReentrant
                refundETHLeftover(params.refundTo)
                chargeETHFees(fees, params.amount)
            {
                // Execute fill
                _buy(
                    takerBid,
                    makerAsk,
                    params.fillTo,
                    params.revertIfIncomplete,
                    params.amount
                );
            }
            // --- Multiple ETH listings ---
            function acceptETHListings(
                ILooksRare.TakerOrder[] calldata takerBids,
                ILooksRare.MakerOrder[] calldata makerAsks,
                ETHListingParams calldata params,
                Fee[] calldata fees
            )
                external
                payable
                nonReentrant
                refundETHLeftover(params.refundTo)
                chargeETHFees(fees, params.amount)
            {
                // LooksRare does not support batch filling so we fill orders one by one
                for (uint256 i = 0; i < takerBids.length; ) {
                    // Use `memory` to avoid `Stack too deep` errors
                    ILooksRare.TakerOrder memory takerBid = takerBids[i];
                    // Execute fill
                    _buy(
                        takerBids[i],
                        makerAsks[i],
                        params.fillTo,
                        params.revertIfIncomplete,
                        takerBid.price
                    );
                    unchecked {
                        ++i;
                    }
                }
            }
            // --- [ERC721] Single offer ---
            function acceptERC721Offer(
                ILooksRare.TakerOrder calldata takerAsk,
                ILooksRare.MakerOrder calldata makerBid,
                OfferParams calldata params,
                Fee[] calldata fees
            ) external nonReentrant {
                IERC721 collection = IERC721(address(makerBid.collection));
                // Approve the transfer manager if needed
                _approveERC721IfNeeded(collection, ERC721_TRANSFER_MANAGER);
                // Execute the fill
                _sell(
                    takerAsk,
                    makerBid,
                    params.fillTo,
                    params.revertIfIncomplete,
                    fees
                );
                // Refund any ERC721 leftover
                _sendAllERC721(params.refundTo, collection, takerAsk.tokenId);
            }
            // --- [ERC1155] Single offer ---
            function acceptERC1155Offer(
                ILooksRare.TakerOrder calldata takerAsk,
                ILooksRare.MakerOrder calldata makerBid,
                OfferParams calldata params,
                Fee[] calldata fees
            ) external nonReentrant {
                IERC1155 collection = IERC1155(address(makerBid.collection));
                // Approve the transfer manager if needed
                _approveERC1155IfNeeded(collection, ERC1155_TRANSFER_MANAGER);
                // Execute the fill
                _sell(
                    takerAsk,
                    makerBid,
                    params.fillTo,
                    params.revertIfIncomplete,
                    fees
                );
                // Refund any ERC1155 leftover
                _sendAllERC1155(params.refundTo, collection, takerAsk.tokenId);
            }
            // --- ERC721 / ERC1155 hooks ---
            // Single token offer acceptance can be done approval-less by using the
            // standard `safeTransferFrom` method together with specifying data for
            // further contract calls. An example:
            // `safeTransferFrom(
            //      0xWALLET,
            //      0xMODULE,
            //      TOKEN_ID,
            //      0xABI_ENCODED_ROUTER_EXECUTION_CALLDATA_FOR_OFFER_ACCEPTANCE
            // )`
            function onERC721Received(
                address, // operator,
                address, // from
                uint256, // tokenId,
                bytes calldata data
            ) external returns (bytes4) {
                if (data.length > 0) {
                    _makeCall(router, data, 0);
                }
                return this.onERC721Received.selector;
            }
            function onERC1155Received(
                address, // operator
                address, // from
                uint256, // tokenId
                uint256, // amount
                bytes calldata data
            ) external returns (bytes4) {
                if (data.length > 0) {
                    _makeCall(router, data, 0);
                }
                return this.onERC1155Received.selector;
            }
            // --- Internal ---
            function _buy(
                ILooksRare.TakerOrder calldata takerBid,
                ILooksRare.MakerOrder calldata makerAsk,
                address receiver,
                bool revertIfIncomplete,
                uint256 value
            ) internal {
                // Execute the fill
                try
                    EXCHANGE.matchAskWithTakerBidUsingETHAndWETH{value: value}(
                        takerBid,
                        makerAsk
                    )
                {
                    IERC165 collection = makerAsk.collection;
                    // Forward any token to the specified receiver
                    bool isERC721 = collection.supportsInterface(ERC721_INTERFACE);
                    if (isERC721) {
                        IERC721(address(collection)).safeTransferFrom(
                            address(this),
                            receiver,
                            takerBid.tokenId
                        );
                    } else {
                        bool isERC1155 = collection.supportsInterface(
                            ERC1155_INTERFACE
                        );
                        if (isERC1155) {
                            IERC1155(address(collection)).safeTransferFrom(
                                address(this),
                                receiver,
                                takerBid.tokenId,
                                makerAsk.amount,
                                ""
                            );
                        }
                    }
                } catch {
                    // Revert if specified
                    if (revertIfIncomplete) {
                        revert UnsuccessfulFill();
                    }
                }
            }
            function _sell(
                ILooksRare.TakerOrder calldata takerAsk,
                ILooksRare.MakerOrder calldata makerBid,
                address receiver,
                bool revertIfIncomplete,
                Fee[] calldata fees
            ) internal {
                // Execute the fill
                try EXCHANGE.matchBidWithTakerAsk(takerAsk, makerBid) {
                    // Pay fees
                    uint256 feesLength = fees.length;
                    for (uint256 i; i < feesLength; ) {
                        Fee memory fee = fees[i];
                        _sendERC20(fee.recipient, fee.amount, makerBid.currency);
                        unchecked {
                            ++i;
                        }
                    }
                    // Forward any left payment to the specified receiver
                    _sendAllERC20(receiver, makerBid.currency);
                } catch {
                    // Revert if specified
                    if (revertIfIncomplete) {
                        revert UnsuccessfulFill();
                    }
                }
            }
        }
        

        File 3 of 5: LooksRareExchange
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        // OpenZeppelin contracts
        import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
        import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
        import {IERC20, SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
        // LooksRare interfaces
        import {ICurrencyManager} from "./interfaces/ICurrencyManager.sol";
        import {IExecutionManager} from "./interfaces/IExecutionManager.sol";
        import {IExecutionStrategy} from "./interfaces/IExecutionStrategy.sol";
        import {IRoyaltyFeeManager} from "./interfaces/IRoyaltyFeeManager.sol";
        import {ILooksRareExchange} from "./interfaces/ILooksRareExchange.sol";
        import {ITransferManagerNFT} from "./interfaces/ITransferManagerNFT.sol";
        import {ITransferSelectorNFT} from "./interfaces/ITransferSelectorNFT.sol";
        import {IWETH} from "./interfaces/IWETH.sol";
        // LooksRare libraries
        import {OrderTypes} from "./libraries/OrderTypes.sol";
        import {SignatureChecker} from "./libraries/SignatureChecker.sol";
        /**
         * @title LooksRareExchange
         * @notice It is the core contract of the LooksRare exchange.
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         */
        contract LooksRareExchange is ILooksRareExchange, ReentrancyGuard, Ownable {
            using SafeERC20 for IERC20;
            using OrderTypes for OrderTypes.MakerOrder;
            using OrderTypes for OrderTypes.TakerOrder;
            address public immutable WETH;
            bytes32 public immutable DOMAIN_SEPARATOR;
            address public protocolFeeRecipient;
            ICurrencyManager public currencyManager;
            IExecutionManager public executionManager;
            IRoyaltyFeeManager public royaltyFeeManager;
            ITransferSelectorNFT public transferSelectorNFT;
            mapping(address => uint256) public userMinOrderNonce;
            mapping(address => mapping(uint256 => bool)) private _isUserOrderNonceExecutedOrCancelled;
            event CancelAllOrders(address indexed user, uint256 newMinNonce);
            event CancelMultipleOrders(address indexed user, uint256[] orderNonces);
            event NewCurrencyManager(address indexed currencyManager);
            event NewExecutionManager(address indexed executionManager);
            event NewProtocolFeeRecipient(address indexed protocolFeeRecipient);
            event NewRoyaltyFeeManager(address indexed royaltyFeeManager);
            event NewTransferSelectorNFT(address indexed transferSelectorNFT);
            event RoyaltyPayment(
                address indexed collection,
                uint256 indexed tokenId,
                address indexed royaltyRecipient,
                address currency,
                uint256 amount
            );
            event TakerAsk(
                bytes32 orderHash, // bid hash of the maker order
                uint256 orderNonce, // user order nonce
                address indexed taker, // sender address for the taker ask order
                address indexed maker, // maker address of the initial bid order
                address indexed strategy, // strategy that defines the execution
                address currency, // currency address
                address collection, // collection address
                uint256 tokenId, // tokenId transferred
                uint256 amount, // amount of tokens transferred
                uint256 price // final transacted price
            );
            event TakerBid(
                bytes32 orderHash, // ask hash of the maker order
                uint256 orderNonce, // user order nonce
                address indexed taker, // sender address for the taker bid order
                address indexed maker, // maker address of the initial ask order
                address indexed strategy, // strategy that defines the execution
                address currency, // currency address
                address collection, // collection address
                uint256 tokenId, // tokenId transferred
                uint256 amount, // amount of tokens transferred
                uint256 price // final transacted price
            );
            /**
             * @notice Constructor
             * @param _currencyManager currency manager address
             * @param _executionManager execution manager address
             * @param _royaltyFeeManager royalty fee manager address
             * @param _WETH wrapped ether address (for other chains, use wrapped native asset)
             * @param _protocolFeeRecipient protocol fee recipient
             */
            constructor(
                address _currencyManager,
                address _executionManager,
                address _royaltyFeeManager,
                address _WETH,
                address _protocolFeeRecipient
            ) {
                // Calculate the domain separator
                DOMAIN_SEPARATOR = keccak256(
                    abi.encode(
                        0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f, // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                        0xda9101ba92939daf4bb2e18cd5f942363b9297fbc3232c9dd964abb1fb70ed71, // keccak256("LooksRareExchange")
                        0xc89efdaa54c0f20c7adf612882df0950f5a951637e0307cdcb4c672f298b8bc6, // keccak256(bytes("1")) for versionId = 1
                        block.chainid,
                        address(this)
                    )
                );
                currencyManager = ICurrencyManager(_currencyManager);
                executionManager = IExecutionManager(_executionManager);
                royaltyFeeManager = IRoyaltyFeeManager(_royaltyFeeManager);
                WETH = _WETH;
                protocolFeeRecipient = _protocolFeeRecipient;
            }
            /**
             * @notice Cancel all pending orders for a sender
             * @param minNonce minimum user nonce
             */
            function cancelAllOrdersForSender(uint256 minNonce) external {
                require(minNonce > userMinOrderNonce[msg.sender], "Cancel: Order nonce lower than current");
                require(minNonce < userMinOrderNonce[msg.sender] + 500000, "Cancel: Cannot cancel more orders");
                userMinOrderNonce[msg.sender] = minNonce;
                emit CancelAllOrders(msg.sender, minNonce);
            }
            /**
             * @notice Cancel maker orders
             * @param orderNonces array of order nonces
             */
            function cancelMultipleMakerOrders(uint256[] calldata orderNonces) external {
                require(orderNonces.length > 0, "Cancel: Cannot be empty");
                for (uint256 i = 0; i < orderNonces.length; i++) {
                    require(orderNonces[i] >= userMinOrderNonce[msg.sender], "Cancel: Order nonce lower than current");
                    _isUserOrderNonceExecutedOrCancelled[msg.sender][orderNonces[i]] = true;
                }
                emit CancelMultipleOrders(msg.sender, orderNonces);
            }
            /**
             * @notice Match ask with a taker bid order using ETH
             * @param takerBid taker bid order
             * @param makerAsk maker ask order
             */
            function matchAskWithTakerBidUsingETHAndWETH(
                OrderTypes.TakerOrder calldata takerBid,
                OrderTypes.MakerOrder calldata makerAsk
            ) external payable override nonReentrant {
                require((makerAsk.isOrderAsk) && (!takerBid.isOrderAsk), "Order: Wrong sides");
                require(makerAsk.currency == WETH, "Order: Currency must be WETH");
                require(msg.sender == takerBid.taker, "Order: Taker must be the sender");
                // If not enough ETH to cover the price, use WETH
                if (takerBid.price > msg.value) {
                    IERC20(WETH).safeTransferFrom(msg.sender, address(this), (takerBid.price - msg.value));
                } else {
                    require(takerBid.price == msg.value, "Order: Msg.value too high");
                }
                // Wrap ETH sent to this contract
                IWETH(WETH).deposit{value: msg.value}();
                // Check the maker ask order
                bytes32 askHash = makerAsk.hash();
                _validateOrder(makerAsk, askHash);
                // Retrieve execution parameters
                (bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerAsk.strategy)
                    .canExecuteTakerBid(takerBid, makerAsk);
                require(isExecutionValid, "Strategy: Execution invalid");
                // Update maker ask order status to true (prevents replay)
                _isUserOrderNonceExecutedOrCancelled[makerAsk.signer][makerAsk.nonce] = true;
                // Execution part 1/2
                _transferFeesAndFundsWithWETH(
                    makerAsk.strategy,
                    makerAsk.collection,
                    tokenId,
                    makerAsk.signer,
                    takerBid.price,
                    makerAsk.minPercentageToAsk
                );
                // Execution part 2/2
                _transferNonFungibleToken(makerAsk.collection, makerAsk.signer, takerBid.taker, tokenId, amount);
                emit TakerBid(
                    askHash,
                    makerAsk.nonce,
                    takerBid.taker,
                    makerAsk.signer,
                    makerAsk.strategy,
                    makerAsk.currency,
                    makerAsk.collection,
                    tokenId,
                    amount,
                    takerBid.price
                );
            }
            /**
             * @notice Match a takerBid with a matchAsk
             * @param takerBid taker bid order
             * @param makerAsk maker ask order
             */
            function matchAskWithTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
                external
                override
                nonReentrant
            {
                require((makerAsk.isOrderAsk) && (!takerBid.isOrderAsk), "Order: Wrong sides");
                require(msg.sender == takerBid.taker, "Order: Taker must be the sender");
                // Check the maker ask order
                bytes32 askHash = makerAsk.hash();
                _validateOrder(makerAsk, askHash);
                (bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerAsk.strategy)
                    .canExecuteTakerBid(takerBid, makerAsk);
                require(isExecutionValid, "Strategy: Execution invalid");
                // Update maker ask order status to true (prevents replay)
                _isUserOrderNonceExecutedOrCancelled[makerAsk.signer][makerAsk.nonce] = true;
                // Execution part 1/2
                _transferFeesAndFunds(
                    makerAsk.strategy,
                    makerAsk.collection,
                    tokenId,
                    makerAsk.currency,
                    msg.sender,
                    makerAsk.signer,
                    takerBid.price,
                    makerAsk.minPercentageToAsk
                );
                // Execution part 2/2
                _transferNonFungibleToken(makerAsk.collection, makerAsk.signer, takerBid.taker, tokenId, amount);
                emit TakerBid(
                    askHash,
                    makerAsk.nonce,
                    takerBid.taker,
                    makerAsk.signer,
                    makerAsk.strategy,
                    makerAsk.currency,
                    makerAsk.collection,
                    tokenId,
                    amount,
                    takerBid.price
                );
            }
            /**
             * @notice Match a takerAsk with a makerBid
             * @param takerAsk taker ask order
             * @param makerBid maker bid order
             */
            function matchBidWithTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
                external
                override
                nonReentrant
            {
                require((!makerBid.isOrderAsk) && (takerAsk.isOrderAsk), "Order: Wrong sides");
                require(msg.sender == takerAsk.taker, "Order: Taker must be the sender");
                // Check the maker bid order
                bytes32 bidHash = makerBid.hash();
                _validateOrder(makerBid, bidHash);
                (bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerBid.strategy)
                    .canExecuteTakerAsk(takerAsk, makerBid);
                require(isExecutionValid, "Strategy: Execution invalid");
                // Update maker bid order status to true (prevents replay)
                _isUserOrderNonceExecutedOrCancelled[makerBid.signer][makerBid.nonce] = true;
                // Execution part 1/2
                _transferNonFungibleToken(makerBid.collection, msg.sender, makerBid.signer, tokenId, amount);
                // Execution part 2/2
                _transferFeesAndFunds(
                    makerBid.strategy,
                    makerBid.collection,
                    tokenId,
                    makerBid.currency,
                    makerBid.signer,
                    takerAsk.taker,
                    takerAsk.price,
                    takerAsk.minPercentageToAsk
                );
                emit TakerAsk(
                    bidHash,
                    makerBid.nonce,
                    takerAsk.taker,
                    makerBid.signer,
                    makerBid.strategy,
                    makerBid.currency,
                    makerBid.collection,
                    tokenId,
                    amount,
                    takerAsk.price
                );
            }
            /**
             * @notice Update currency manager
             * @param _currencyManager new currency manager address
             */
            function updateCurrencyManager(address _currencyManager) external onlyOwner {
                require(_currencyManager != address(0), "Owner: Cannot be null address");
                currencyManager = ICurrencyManager(_currencyManager);
                emit NewCurrencyManager(_currencyManager);
            }
            /**
             * @notice Update execution manager
             * @param _executionManager new execution manager address
             */
            function updateExecutionManager(address _executionManager) external onlyOwner {
                require(_executionManager != address(0), "Owner: Cannot be null address");
                executionManager = IExecutionManager(_executionManager);
                emit NewExecutionManager(_executionManager);
            }
            /**
             * @notice Update protocol fee and recipient
             * @param _protocolFeeRecipient new recipient for protocol fees
             */
            function updateProtocolFeeRecipient(address _protocolFeeRecipient) external onlyOwner {
                protocolFeeRecipient = _protocolFeeRecipient;
                emit NewProtocolFeeRecipient(_protocolFeeRecipient);
            }
            /**
             * @notice Update royalty fee manager
             * @param _royaltyFeeManager new fee manager address
             */
            function updateRoyaltyFeeManager(address _royaltyFeeManager) external onlyOwner {
                require(_royaltyFeeManager != address(0), "Owner: Cannot be null address");
                royaltyFeeManager = IRoyaltyFeeManager(_royaltyFeeManager);
                emit NewRoyaltyFeeManager(_royaltyFeeManager);
            }
            /**
             * @notice Update transfer selector NFT
             * @param _transferSelectorNFT new transfer selector address
             */
            function updateTransferSelectorNFT(address _transferSelectorNFT) external onlyOwner {
                require(_transferSelectorNFT != address(0), "Owner: Cannot be null address");
                transferSelectorNFT = ITransferSelectorNFT(_transferSelectorNFT);
                emit NewTransferSelectorNFT(_transferSelectorNFT);
            }
            /**
             * @notice Check whether user order nonce is executed or cancelled
             * @param user address of user
             * @param orderNonce nonce of the order
             */
            function isUserOrderNonceExecutedOrCancelled(address user, uint256 orderNonce) external view returns (bool) {
                return _isUserOrderNonceExecutedOrCancelled[user][orderNonce];
            }
            /**
             * @notice Transfer fees and funds to royalty recipient, protocol, and seller
             * @param strategy address of the execution strategy
             * @param collection non fungible token address for the transfer
             * @param tokenId tokenId
             * @param currency currency being used for the purchase (e.g., WETH/USDC)
             * @param from sender of the funds
             * @param to seller's recipient
             * @param amount amount being transferred (in currency)
             * @param minPercentageToAsk minimum percentage of the gross amount that goes to ask
             */
            function _transferFeesAndFunds(
                address strategy,
                address collection,
                uint256 tokenId,
                address currency,
                address from,
                address to,
                uint256 amount,
                uint256 minPercentageToAsk
            ) internal {
                // Initialize the final amount that is transferred to seller
                uint256 finalSellerAmount = amount;
                // 1. Protocol fee
                {
                    uint256 protocolFeeAmount = _calculateProtocolFee(strategy, amount);
                    // Check if the protocol fee is different than 0 for this strategy
                    if ((protocolFeeRecipient != address(0)) && (protocolFeeAmount != 0)) {
                        IERC20(currency).safeTransferFrom(from, protocolFeeRecipient, protocolFeeAmount);
                        finalSellerAmount -= protocolFeeAmount;
                    }
                }
                // 2. Royalty fee
                {
                    (address royaltyFeeRecipient, uint256 royaltyFeeAmount) = royaltyFeeManager
                        .calculateRoyaltyFeeAndGetRecipient(collection, tokenId, amount);
                    // Check if there is a royalty fee and that it is different to 0
                    if ((royaltyFeeRecipient != address(0)) && (royaltyFeeAmount != 0)) {
                        IERC20(currency).safeTransferFrom(from, royaltyFeeRecipient, royaltyFeeAmount);
                        finalSellerAmount -= royaltyFeeAmount;
                        emit RoyaltyPayment(collection, tokenId, royaltyFeeRecipient, currency, royaltyFeeAmount);
                    }
                }
                require((finalSellerAmount * 10000) >= (minPercentageToAsk * amount), "Fees: Higher than expected");
                // 3. Transfer final amount (post-fees) to seller
                {
                    IERC20(currency).safeTransferFrom(from, to, finalSellerAmount);
                }
            }
            /**
             * @notice Transfer fees and funds to royalty recipient, protocol, and seller
             * @param strategy address of the execution strategy
             * @param collection non fungible token address for the transfer
             * @param tokenId tokenId
             * @param to seller's recipient
             * @param amount amount being transferred (in currency)
             * @param minPercentageToAsk minimum percentage of the gross amount that goes to ask
             */
            function _transferFeesAndFundsWithWETH(
                address strategy,
                address collection,
                uint256 tokenId,
                address to,
                uint256 amount,
                uint256 minPercentageToAsk
            ) internal {
                // Initialize the final amount that is transferred to seller
                uint256 finalSellerAmount = amount;
                // 1. Protocol fee
                {
                    uint256 protocolFeeAmount = _calculateProtocolFee(strategy, amount);
                    // Check if the protocol fee is different than 0 for this strategy
                    if ((protocolFeeRecipient != address(0)) && (protocolFeeAmount != 0)) {
                        IERC20(WETH).safeTransfer(protocolFeeRecipient, protocolFeeAmount);
                        finalSellerAmount -= protocolFeeAmount;
                    }
                }
                // 2. Royalty fee
                {
                    (address royaltyFeeRecipient, uint256 royaltyFeeAmount) = royaltyFeeManager
                        .calculateRoyaltyFeeAndGetRecipient(collection, tokenId, amount);
                    // Check if there is a royalty fee and that it is different to 0
                    if ((royaltyFeeRecipient != address(0)) && (royaltyFeeAmount != 0)) {
                        IERC20(WETH).safeTransfer(royaltyFeeRecipient, royaltyFeeAmount);
                        finalSellerAmount -= royaltyFeeAmount;
                        emit RoyaltyPayment(collection, tokenId, royaltyFeeRecipient, address(WETH), royaltyFeeAmount);
                    }
                }
                require((finalSellerAmount * 10000) >= (minPercentageToAsk * amount), "Fees: Higher than expected");
                // 3. Transfer final amount (post-fees) to seller
                {
                    IERC20(WETH).safeTransfer(to, finalSellerAmount);
                }
            }
            /**
             * @notice Transfer NFT
             * @param collection address of the token collection
             * @param from address of the sender
             * @param to address of the recipient
             * @param tokenId tokenId
             * @param amount amount of tokens (1 for ERC721, 1+ for ERC1155)
             * @dev For ERC721, amount is not used
             */
            function _transferNonFungibleToken(
                address collection,
                address from,
                address to,
                uint256 tokenId,
                uint256 amount
            ) internal {
                // Retrieve the transfer manager address
                address transferManager = transferSelectorNFT.checkTransferManagerForToken(collection);
                // If no transfer manager found, it returns address(0)
                require(transferManager != address(0), "Transfer: No NFT transfer manager available");
                // If one is found, transfer the token
                ITransferManagerNFT(transferManager).transferNonFungibleToken(collection, from, to, tokenId, amount);
            }
            /**
             * @notice Calculate protocol fee for an execution strategy
             * @param executionStrategy strategy
             * @param amount amount to transfer
             */
            function _calculateProtocolFee(address executionStrategy, uint256 amount) internal view returns (uint256) {
                uint256 protocolFee = IExecutionStrategy(executionStrategy).viewProtocolFee();
                return (protocolFee * amount) / 10000;
            }
            /**
             * @notice Verify the validity of the maker order
             * @param makerOrder maker order
             * @param orderHash computed hash for the order
             */
            function _validateOrder(OrderTypes.MakerOrder calldata makerOrder, bytes32 orderHash) internal view {
                // Verify whether order nonce has expired
                require(
                    (!_isUserOrderNonceExecutedOrCancelled[makerOrder.signer][makerOrder.nonce]) &&
                        (makerOrder.nonce >= userMinOrderNonce[makerOrder.signer]),
                    "Order: Matching order expired"
                );
                // Verify the signer is not address(0)
                require(makerOrder.signer != address(0), "Order: Invalid signer");
                // Verify the amount is not 0
                require(makerOrder.amount > 0, "Order: Amount cannot be 0");
                // Verify the validity of the signature
                require(
                    SignatureChecker.verify(
                        orderHash,
                        makerOrder.signer,
                        makerOrder.v,
                        makerOrder.r,
                        makerOrder.s,
                        DOMAIN_SEPARATOR
                    ),
                    "Signature: Invalid"
                );
                // Verify whether the currency is whitelisted
                require(currencyManager.isCurrencyWhitelisted(makerOrder.currency), "Currency: Not whitelisted");
                // Verify whether strategy can be executed
                require(executionManager.isStrategyWhitelisted(makerOrder.strategy), "Strategy: Not whitelisted");
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (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 Returns the address of the current owner.
             */
            function owner() public view virtual returns (address) {
                return _owner;
            }
            /**
             * @dev Throws if called by any account other than the owner.
             */
            modifier onlyOwner() {
                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 (security/ReentrancyGuard.sol)
        pragma solidity ^0.8.0;
        /**
         * @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 ReentrancyGuard {
            // 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;
            constructor() {
                _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;
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
        pragma solidity ^0.8.0;
        import "../IERC20.sol";
        import "../../../utils/Address.sol";
        /**
         * @title SafeERC20
         * @dev Wrappers around ERC20 operations that throw on failure (when the token
         * contract returns false). Tokens that return no value (and instead revert or
         * throw on failure) are also supported, non-reverting calls are assumed to be
         * successful.
         * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
         * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
         */
        library SafeERC20 {
            using Address for address;
            function safeTransfer(
                IERC20 token,
                address to,
                uint256 value
            ) internal {
                _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
            }
            function safeTransferFrom(
                IERC20 token,
                address from,
                address to,
                uint256 value
            ) internal {
                _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
            }
            /**
             * @dev Deprecated. This function has issues similar to the ones found in
             * {IERC20-approve}, and its usage is discouraged.
             *
             * Whenever possible, use {safeIncreaseAllowance} and
             * {safeDecreaseAllowance} instead.
             */
            function safeApprove(
                IERC20 token,
                address spender,
                uint256 value
            ) internal {
                // safeApprove should only be called when setting an initial allowance,
                // or when resetting it to zero. To increase and decrease it, use
                // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                require(
                    (value == 0) || (token.allowance(address(this), spender) == 0),
                    "SafeERC20: approve from non-zero to non-zero allowance"
                );
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
            }
            function safeIncreaseAllowance(
                IERC20 token,
                address spender,
                uint256 value
            ) internal {
                uint256 newAllowance = token.allowance(address(this), spender) + value;
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
            }
            function safeDecreaseAllowance(
                IERC20 token,
                address spender,
                uint256 value
            ) internal {
                unchecked {
                    uint256 oldAllowance = token.allowance(address(this), spender);
                    require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                    uint256 newAllowance = oldAllowance - value;
                    _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                }
            }
            /**
             * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
             * on the return value: the return value is optional (but if data is returned, it must not be false).
             * @param token The token targeted by the call.
             * @param data The call data (encoded using abi.encode or one of its variants).
             */
            function _callOptionalReturn(IERC20 token, bytes memory data) private {
                // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                // the target address contains contract code and also asserts for success in the low-level call.
                bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                if (returndata.length > 0) {
                    // Return data is optional
                    require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                }
            }
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        interface ICurrencyManager {
            function addCurrency(address currency) external;
            function removeCurrency(address currency) external;
            function isCurrencyWhitelisted(address currency) external view returns (bool);
            function viewWhitelistedCurrencies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
            function viewCountWhitelistedCurrencies() external view returns (uint256);
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        interface IExecutionManager {
            function addStrategy(address strategy) external;
            function removeStrategy(address strategy) external;
            function isStrategyWhitelisted(address strategy) external view returns (bool);
            function viewWhitelistedStrategies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
            function viewCountWhitelistedStrategies() external view returns (uint256);
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        import {OrderTypes} from "../libraries/OrderTypes.sol";
        interface IExecutionStrategy {
            function canExecuteTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
                external
                view
                returns (
                    bool,
                    uint256,
                    uint256
                );
            function canExecuteTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
                external
                view
                returns (
                    bool,
                    uint256,
                    uint256
                );
            function viewProtocolFee() external view returns (uint256);
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        interface IRoyaltyFeeManager {
            function calculateRoyaltyFeeAndGetRecipient(
                address collection,
                uint256 tokenId,
                uint256 amount
            ) external view returns (address, uint256);
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        import {OrderTypes} from "../libraries/OrderTypes.sol";
        interface ILooksRareExchange {
            function matchAskWithTakerBidUsingETHAndWETH(
                OrderTypes.TakerOrder calldata takerBid,
                OrderTypes.MakerOrder calldata makerAsk
            ) external payable;
            function matchAskWithTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
                external;
            function matchBidWithTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
                external;
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        interface ITransferManagerNFT {
            function transferNonFungibleToken(
                address collection,
                address from,
                address to,
                uint256 tokenId,
                uint256 amount
            ) external;
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        interface ITransferSelectorNFT {
            function checkTransferManagerForToken(address collection) external view returns (address);
        }
        // SPDX-License-Identifier: GNU
        pragma solidity >=0.5.0;
        interface IWETH {
            function deposit() external payable;
            function transfer(address to, uint256 value) external returns (bool);
            function withdraw(uint256) external;
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        /**
         * @title OrderTypes
         * @notice This library contains order types for the LooksRare exchange.
         */
        library OrderTypes {
            // keccak256("MakerOrder(bool isOrderAsk,address signer,address collection,uint256 price,uint256 tokenId,uint256 amount,address strategy,address currency,uint256 nonce,uint256 startTime,uint256 endTime,uint256 minPercentageToAsk,bytes params)")
            bytes32 internal constant MAKER_ORDER_HASH = 0x40261ade532fa1d2c7293df30aaadb9b3c616fae525a0b56d3d411c841a85028;
            struct MakerOrder {
                bool isOrderAsk; // true --> ask / false --> bid
                address signer; // signer of the maker order
                address collection; // collection address
                uint256 price; // price (used as )
                uint256 tokenId; // id of the token
                uint256 amount; // amount of tokens to sell/purchase (must be 1 for ERC721, 1+ for ERC1155)
                address strategy; // strategy for trade execution (e.g., DutchAuction, StandardSaleForFixedPrice)
                address currency; // currency (e.g., WETH)
                uint256 nonce; // order nonce (must be unique unless new maker order is meant to override existing one e.g., lower ask price)
                uint256 startTime; // startTime in timestamp
                uint256 endTime; // endTime in timestamp
                uint256 minPercentageToAsk; // slippage protection (9000 --> 90% of the final price must return to ask)
                bytes params; // additional parameters
                uint8 v; // v: parameter (27 or 28)
                bytes32 r; // r: parameter
                bytes32 s; // s: parameter
            }
            struct TakerOrder {
                bool isOrderAsk; // true --> ask / false --> bid
                address taker; // msg.sender
                uint256 price; // final price for the purchase
                uint256 tokenId;
                uint256 minPercentageToAsk; // // slippage protection (9000 --> 90% of the final price must return to ask)
                bytes params; // other params (e.g., tokenId)
            }
            function hash(MakerOrder memory makerOrder) internal pure returns (bytes32) {
                return
                    keccak256(
                        abi.encode(
                            MAKER_ORDER_HASH,
                            makerOrder.isOrderAsk,
                            makerOrder.signer,
                            makerOrder.collection,
                            makerOrder.price,
                            makerOrder.tokenId,
                            makerOrder.amount,
                            makerOrder.strategy,
                            makerOrder.currency,
                            makerOrder.nonce,
                            makerOrder.startTime,
                            makerOrder.endTime,
                            makerOrder.minPercentageToAsk,
                            keccak256(makerOrder.params)
                        )
                    );
            }
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        import {Address} from "@openzeppelin/contracts/utils/Address.sol";
        import {IERC1271} from "@openzeppelin/contracts/interfaces/IERC1271.sol";
        /**
         * @title SignatureChecker
         * @notice This library allows verification of signatures for both EOAs and contracts.
         */
        library SignatureChecker {
            /**
             * @notice Recovers the signer of a signature (for EOA)
             * @param hash the hash containing the signed mesage
             * @param v parameter (27 or 28). This prevents maleability since the public key recovery equation has two possible solutions.
             * @param r parameter
             * @param s parameter
             */
            function recover(
                bytes32 hash,
                uint8 v,
                bytes32 r,
                bytes32 s
            ) internal pure returns (address) {
                // https://ethereum.stackexchange.com/questions/83174/is-it-best-practice-to-check-signature-malleability-in-ecrecover
                // https://crypto.iacr.org/2019/affevents/wac/medias/Heninger-BiasedNonceSense.pdf
                require(
                    uint256(s) <= 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
                    "Signature: Invalid s parameter"
                );
                require(v == 27 || v == 28, "Signature: Invalid v parameter");
                // If the signature is valid (and not malleable), return the signer address
                address signer = ecrecover(hash, v, r, s);
                require(signer != address(0), "Signature: Invalid signer");
                return signer;
            }
            /**
             * @notice Returns whether the signer matches the signed message
             * @param hash the hash containing the signed mesage
             * @param signer the signer address to confirm message validity
             * @param v parameter (27 or 28)
             * @param r parameter
             * @param s parameter
             * @param domainSeparator paramer to prevent signature being executed in other chains and environments
             * @return true --> if valid // false --> if invalid
             */
            function verify(
                bytes32 hash,
                address signer,
                uint8 v,
                bytes32 r,
                bytes32 s,
                bytes32 domainSeparator
            ) internal view returns (bool) {
                // \\x19\\x01 is the standardized encoding prefix
                // https://eips.ethereum.org/EIPS/eip-712#specification
                bytes32 digest = keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, hash));
                if (Address.isContract(signer)) {
                    // 0x1626ba7e is the interfaceId for signature contracts (see IERC1271)
                    return IERC1271(signer).isValidSignature(digest, abi.encodePacked(r, s, v)) == 0x1626ba7e;
                } else {
                    return recover(digest, v, r, s) == signer;
                }
            }
        }
        // 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 v4.4.1 (token/ERC20/IERC20.sol)
        pragma solidity ^0.8.0;
        /**
         * @dev Interface of the ERC20 standard as defined in the EIP.
         */
        interface IERC20 {
            /**
             * @dev Returns the amount of tokens in existence.
             */
            function totalSupply() external view returns (uint256);
            /**
             * @dev Returns the amount of tokens owned by `account`.
             */
            function balanceOf(address account) external view returns (uint256);
            /**
             * @dev Moves `amount` tokens from the caller's account to `recipient`.
             *
             * Returns a boolean value indicating whether the operation succeeded.
             *
             * Emits a {Transfer} event.
             */
            function transfer(address recipient, uint256 amount) external returns (bool);
            /**
             * @dev Returns the remaining number of tokens that `spender` will be
             * allowed to spend on behalf of `owner` through {transferFrom}. This is
             * zero by default.
             *
             * This value changes when {approve} or {transferFrom} are called.
             */
            function allowance(address owner, address spender) external view returns (uint256);
            /**
             * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
             *
             * Returns a boolean value indicating whether the operation succeeded.
             *
             * IMPORTANT: Beware that changing an allowance with this method brings the risk
             * that someone may use both the old and the new allowance by unfortunate
             * transaction ordering. One possible solution to mitigate this race
             * condition is to first reduce the spender's allowance to 0 and set the
             * desired value afterwards:
             * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
             *
             * Emits an {Approval} event.
             */
            function approve(address spender, uint256 amount) external returns (bool);
            /**
             * @dev Moves `amount` tokens from `sender` to `recipient` using the
             * allowance mechanism. `amount` is then deducted from the caller's
             * allowance.
             *
             * Returns a boolean value indicating whether the operation succeeded.
             *
             * Emits a {Transfer} event.
             */
            function transferFrom(
                address sender,
                address recipient,
                uint256 amount
            ) external returns (bool);
            /**
             * @dev Emitted when `value` tokens are moved from one account (`from`) to
             * another (`to`).
             *
             * Note that `value` may be zero.
             */
            event Transfer(address indexed from, address indexed to, uint256 value);
            /**
             * @dev Emitted when the allowance of a `spender` for an `owner` is set by
             * a call to {approve}. `value` is the new allowance.
             */
            event Approval(address indexed owner, address indexed spender, uint256 value);
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
        pragma solidity ^0.8.0;
        /**
         * @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
             * ====
             */
            function isContract(address account) internal view returns (bool) {
                // This method relies on extcodesize, which returns 0 for contracts in
                // construction, since the code is only stored at the end of the
                // constructor execution.
                uint256 size;
                assembly {
                    size := extcodesize(account)
                }
                return size > 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);
                    }
                }
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (interfaces/IERC1271.sol)
        pragma solidity ^0.8.0;
        /**
         * @dev Interface of the ERC1271 standard signature validation method for
         * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
         *
         * _Available since v4.1._
         */
        interface IERC1271 {
            /**
             * @dev Should return whether the signature provided is valid for the provided data
             * @param hash      Hash of the data to be signed
             * @param signature Signature byte array associated with _data
             */
            function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
        }
        

        File 4 of 5: WETH9
        // Copyright (C) 2015, 2016, 2017 Dapphub
        
        // This program is free software: you can redistribute it and/or modify
        // it under the terms of the GNU General Public License as published by
        // the Free Software Foundation, either version 3 of the License, or
        // (at your option) any later version.
        
        // This program is distributed in the hope that it will be useful,
        // but WITHOUT ANY WARRANTY; without even the implied warranty of
        // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
        // GNU General Public License for more details.
        
        // You should have received a copy of the GNU General Public License
        // along with this program.  If not, see <http://www.gnu.org/licenses/>.
        
        pragma solidity ^0.4.18;
        
        contract WETH9 {
            string public name     = "Wrapped Ether";
            string public symbol   = "WETH";
            uint8  public decimals = 18;
        
            event  Approval(address indexed src, address indexed guy, uint wad);
            event  Transfer(address indexed src, address indexed dst, uint wad);
            event  Deposit(address indexed dst, uint wad);
            event  Withdrawal(address indexed src, uint wad);
        
            mapping (address => uint)                       public  balanceOf;
            mapping (address => mapping (address => uint))  public  allowance;
        
            function() public payable {
                deposit();
            }
            function deposit() public payable {
                balanceOf[msg.sender] += msg.value;
                Deposit(msg.sender, msg.value);
            }
            function withdraw(uint wad) public {
                require(balanceOf[msg.sender] >= wad);
                balanceOf[msg.sender] -= wad;
                msg.sender.transfer(wad);
                Withdrawal(msg.sender, wad);
            }
        
            function totalSupply() public view returns (uint) {
                return this.balance;
            }
        
            function approve(address guy, uint wad) public returns (bool) {
                allowance[msg.sender][guy] = wad;
                Approval(msg.sender, guy, wad);
                return true;
            }
        
            function transfer(address dst, uint wad) public returns (bool) {
                return transferFrom(msg.sender, dst, wad);
            }
        
            function transferFrom(address src, address dst, uint wad)
                public
                returns (bool)
            {
                require(balanceOf[src] >= wad);
        
                if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
                    require(allowance[src][msg.sender] >= wad);
                    allowance[src][msg.sender] -= wad;
                }
        
                balanceOf[src] -= wad;
                balanceOf[dst] += wad;
        
                Transfer(src, dst, wad);
        
                return true;
            }
        }
        
        
        /*
                            GNU GENERAL PUBLIC LICENSE
                               Version 3, 29 June 2007
        
         Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
         Everyone is permitted to copy and distribute verbatim copies
         of this license document, but changing it is not allowed.
        
                                    Preamble
        
          The GNU General Public License is a free, copyleft license for
        software and other kinds of works.
        
          The licenses for most software and other practical works are designed
        to take away your freedom to share and change the works.  By contrast,
        the GNU General Public License is intended to guarantee your freedom to
        share and change all versions of a program--to make sure it remains free
        software for all its users.  We, the Free Software Foundation, use the
        GNU General Public License for most of our software; it applies also to
        any other work released this way by its authors.  You can apply it to
        your programs, too.
        
          When we speak of free software, we are referring to freedom, not
        price.  Our General Public Licenses are designed to make sure that you
        have the freedom to distribute copies of free software (and charge for
        them if you wish), that you receive source code or can get it if you
        want it, that you can change the software or use pieces of it in new
        free programs, and that you know you can do these things.
        
          To protect your rights, we need to prevent others from denying you
        these rights or asking you to surrender the rights.  Therefore, you have
        certain responsibilities if you distribute copies of the software, or if
        you modify it: responsibilities to respect the freedom of others.
        
          For example, if you distribute copies of such a program, whether
        gratis or for a fee, you must pass on to the recipients the same
        freedoms that you received.  You must make sure that they, too, receive
        or can get the source code.  And you must show them these terms so they
        know their rights.
        
          Developers that use the GNU GPL protect your rights with two steps:
        (1) assert copyright on the software, and (2) offer you this License
        giving you legal permission to copy, distribute and/or modify it.
        
          For the developers' and authors' protection, the GPL clearly explains
        that there is no warranty for this free software.  For both users' and
        authors' sake, the GPL requires that modified versions be marked as
        changed, so that their problems will not be attributed erroneously to
        authors of previous versions.
        
          Some devices are designed to deny users access to install or run
        modified versions of the software inside them, although the manufacturer
        can do so.  This is fundamentally incompatible with the aim of
        protecting users' freedom to change the software.  The systematic
        pattern of such abuse occurs in the area of products for individuals to
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        have designed this version of the GPL to prohibit the practice for those
        products.  If such problems arise substantially in other domains, we
        stand ready to extend this provision to those domains in future versions
        of the GPL, as needed to protect the freedom of users.
        
          Finally, every program is threatened constantly by software patents.
        States should not allow patents to restrict development and use of
        software on general-purpose computers, but in those that do, we wish to
        avoid the special danger that patents applied to a free program could
        make it effectively proprietary.  To prevent this, the GPL assures that
        patents cannot be used to render the program non-free.
        
          The precise terms and conditions for copying, distribution and
        modification follow.
        
                               TERMS AND CONDITIONS
        
          0. Definitions.
        
          "This License" refers to version 3 of the GNU General Public License.
        
          "Copyright" also means copyright-like laws that apply to other kinds of
        works, such as semiconductor masks.
        
          "The Program" refers to any copyrightable work licensed under this
        License.  Each licensee is addressed as "you".  "Licensees" and
        "recipients" may be individuals or organizations.
        
          To "modify" a work means to copy from or adapt all or part of the work
        in a fashion requiring copyright permission, other than the making of an
        exact copy.  The resulting work is called a "modified version" of the
        earlier work or a work "based on" the earlier work.
        
          A "covered work" means either the unmodified Program or a work based
        on the Program.
        
          To "propagate" a work means to do anything with it that, without
        permission, would make you directly or secondarily liable for
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        File 5 of 5: CurrencyManager
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
        import {EnumerableSet} from "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
        import {ICurrencyManager} from "./interfaces/ICurrencyManager.sol";
        /**
         * @title CurrencyManager
         * @notice It allows adding/removing currencies for trading on the LooksRare exchange.
         */
        contract CurrencyManager is ICurrencyManager, Ownable {
            using EnumerableSet for EnumerableSet.AddressSet;
            EnumerableSet.AddressSet private _whitelistedCurrencies;
            event CurrencyRemoved(address indexed currency);
            event CurrencyWhitelisted(address indexed currency);
            /**
             * @notice Add a currency in the system
             * @param currency address of the currency to add
             */
            function addCurrency(address currency) external override onlyOwner {
                require(!_whitelistedCurrencies.contains(currency), "Currency: Already whitelisted");
                _whitelistedCurrencies.add(currency);
                emit CurrencyWhitelisted(currency);
            }
            /**
             * @notice Remove a currency from the system
             * @param currency address of the currency to remove
             */
            function removeCurrency(address currency) external override onlyOwner {
                require(_whitelistedCurrencies.contains(currency), "Currency: Not whitelisted");
                _whitelistedCurrencies.remove(currency);
                emit CurrencyRemoved(currency);
            }
            /**
             * @notice Returns if a currency is in the system
             * @param currency address of the currency
             */
            function isCurrencyWhitelisted(address currency) external view override returns (bool) {
                return _whitelistedCurrencies.contains(currency);
            }
            /**
             * @notice View number of whitelisted currencies
             */
            function viewCountWhitelistedCurrencies() external view override returns (uint256) {
                return _whitelistedCurrencies.length();
            }
            /**
             * @notice See whitelisted currencies in the system
             * @param cursor cursor (should start at 0 for first request)
             * @param size size of the response (e.g., 50)
             */
            function viewWhitelistedCurrencies(uint256 cursor, uint256 size)
                external
                view
                override
                returns (address[] memory, uint256)
            {
                uint256 length = size;
                if (length > _whitelistedCurrencies.length() - cursor) {
                    length = _whitelistedCurrencies.length() - cursor;
                }
                address[] memory whitelistedCurrencies = new address[](length);
                for (uint256 i = 0; i < length; i++) {
                    whitelistedCurrencies[i] = _whitelistedCurrencies.at(cursor + i);
                }
                return (whitelistedCurrencies, cursor + length);
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (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 Returns the address of the current owner.
             */
            function owner() public view virtual returns (address) {
                return _owner;
            }
            /**
             * @dev Throws if called by any account other than the owner.
             */
            modifier onlyOwner() {
                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/structs/EnumerableSet.sol)
        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.
         */
        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) {
                return _values(set._inner);
            }
            // 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;
                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 on 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;
                assembly {
                    result := store
                }
                return result;
            }
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        interface ICurrencyManager {
            function addCurrency(address currency) external;
            function removeCurrency(address currency) external;
            function isCurrencyWhitelisted(address currency) external view returns (bool);
            function viewWhitelistedCurrencies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
            function viewCountWhitelistedCurrencies() external view returns (uint256);
        }
        // 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;
            }
        }