ETH Price: $1,790.03 (-1.72%)

Transaction Decoder

Block:
15509535 at Sep-10-2022 03:30:04 PM +UTC
Transaction Fee:
0.004499857242777386 ETH $8.05
Gas Used:
210,239 Gas / 21.403532374 Gwei

Emitted Events:

10 GmStudioCatharsis.ApprovalForAll( owner=[Sender] 0xb64fdc6c2044242e2823b0f7e251dc2fd69cdbd2, operator=0x740FF910...F461b579e, approved=True )
11 GmStudioCatharsis.Transfer( from=0x17a6a2c0491a004f7b342362af078396826c4fe7, to=[Sender] 0xb64fdc6c2044242e2823b0f7e251dc2fd69cdbd2, tokenId=803 )
12 DelegatedPaymentSplitter.PaymentReceived( from=[Receiver] TransparentUpgradeableProxy, amount=78750000000000000 )
13 TransparentUpgradeableProxy.0xe2c49856b032c255ae7e325d18109bc4e22a2804e2e49a017ec0f59f19cd447b( 0xe2c49856b032c255ae7e325d18109bc4e22a2804e2e49a017ec0f59f19cd447b, e5674ef1d786eae581f23bd32dbb77e7c93d30e50d2968e233bf08257716a217, 0000000000000000000000000000000000000000000000000000000000000000, 00000000000000000000000017a6a2c0491a004f7b342362af078396826c4fe7, 0000000000000000000000000000000000000000000000000d67ebe1c5070000 )
14 TransparentUpgradeableProxy.0x3cbb63f144840e5b1b0a38a7c19211d2e89de4d7c5faf8b2d3c1776c302d1d33( 0x3cbb63f144840e5b1b0a38a7c19211d2e89de4d7c5faf8b2d3c1776c302d1d33, 0xe5674ef1d786eae581f23bd32dbb77e7c93d30e50d2968e233bf08257716a217, 00000000000000000000000017a6a2c0491a004f7b342362af078396826c4fe7, 000000000000000000000000b64fdc6c2044242e2823b0f7e251dc2fd69cdbd2, 0000000000000000000000000000000008429c929729800de40d41f863bfb304, 0000000000000000000000000000000000000000000000000001b14ed84f38da, 0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000000000000000000000000000000001, 000000000000000000000000000000000000000000000000000000006344393d, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000160, 0000000000000000000000000000000000000000000000000000000000000180, 0000000000000000000000000000000000000000000000000000000000000260, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000e92596fd6290000, 0000000000000000000000000000000000000000000000000000000000000040, 0000000000000000000000000000000000000000000000000000000000000080, 0000000000000000000000000000000000000000000000000000000000000020, 0000000000000000000000000000000000000000000000000000000000000001, 00000000000000000000000066293a9b1339ca99623e82bc71f88d767f60ad21, 0000000000000000000000000000000000000000000000000000000000000323, 0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000e92596fd6290000, e5674ef1d786eae581f23bd32dbb77e7c93d30e50d2968e233bf08257716a217, 000000000000000000000000f849de01b080adc3a814fabe1e2087475cf2e354, 0000000000000000000000000000000000000000000000000000000000000160, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000180, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000002, 0000000000000000000000000000000000000000000000000000000000001388, 000000000000000000000000d823c605807cc5e6bd6fc0d7e4eea50d3e2d66cd, 00000000000000000000000000000000000000000000000000000000000124f8, 0000000000000000000000001dd7ebdf491e319e7d8bd295938ca524345e679c )

Account State Difference:

  Address   Before After State Difference Code
0x17a6A2C0...6826c4fE7 0.080436354477464914 Eth1.046436354477464914 Eth0.966
(Hiveon Pool)
15,717.330749210378141824 Eth15,717.331863477078141824 Eth0.0011142667
0x1dD7EbDF...4345E679C 18.277671757485000006 Eth18.356421757485000006 Eth0.07875
0x66293A9B...67F60Ad21
0x74312363...65a67EeD3
(X2Y2: Exchange)
0xB64FDc6c...Fd69cDbd2
1.472702930279342422 Eth
Nonce: 216
0.418203073036565036 Eth
Nonce: 217
1.054499857242777386
0xD823C605...d3e2d66cd
(X2Y2: Fee Management)
10.53490719704713138 Eth10.54015719704713138 Eth0.00525

Execution Trace

ETH 1.05 TransparentUpgradeableProxy.357a150b( )
  • ETH 1.05 X2Y2_r1.run( input=[{name:orders, type:tuple[], order:1, indexed:false}, {name:details, type:tuple[], order:2, indexed:false}, {name:shared, type:tuple, order:3, indexed:false, value:[{name:salt, type:uint256, order:1, indexed:false, value:476427171346650, valueString:476427171346650}, {name:deadline, type:uint256, order:2, indexed:false, value:1662834606, valueString:1662834606}, {name:amountToEth, type:uint256, order:3, indexed:false, value:0, valueString:0}, {name:amountToWeth, type:uint256, order:4, indexed:false, value:0, valueString:0}, {name:user, type:address, order:5, indexed:false, value:0xB64FDc6c2044242E2823b0F7e251dc2Fd69cDbd2, valueString:0xB64FDc6c2044242E2823b0F7e251dc2Fd69cDbd2}, {name:canFail, type:bool, order:6, indexed:false, value:false, valueString:False}], valueString:[{name:salt, type:uint256, order:1, indexed:false, value:476427171346650, valueString:476427171346650}, {name:deadline, type:uint256, order:2, indexed:false, value:1662834606, valueString:1662834606}, {name:amountToEth, type:uint256, order:3, indexed:false, value:0, valueString:0}, {name:amountToWeth, type:uint256, order:4, indexed:false, value:0, valueString:0}, {name:user, type:address, order:5, indexed:false, value:0xB64FDc6c2044242E2823b0F7e251dc2Fd69cDbd2, valueString:0xB64FDc6c2044242E2823b0F7e251dc2Fd69cDbd2}, {name:canFail, type:bool, order:6, indexed:false, value:false, valueString:False}]}, {name:r, type:bytes32, order:4, indexed:false, value:88DE6556D7F458773B7A5F73B19E17D52BD77C8CFA491EEA2143457F8908FB40, valueString:88DE6556D7F458773B7A5F73B19E17D52BD77C8CFA491EEA2143457F8908FB40}, {name:s, type:bytes32, order:5, indexed:false, value:6984101D99078172DCF346FC64BC4F6FE3244AC70116B91D11DE1CB84A7E3178, valueString:6984101D99078172DCF346FC64BC4F6FE3244AC70116B91D11DE1CB84A7E3178}, {name:v, type:uint8, order:6, indexed:false, value:28, valueString:28}] )
    • Null: 0x000...001.4d6c71b4( )
    • Null: 0x000...001.e408ea13( )
    • ERC721Delegate.STATICCALL( )
    • ERC721Delegate.executeSell( seller=0x17a6A2C0491a004F7b342362aF078396826c4fE7, buyer=0xB64FDc6c2044242E2823b0F7e251dc2Fd69cDbd2, data=0x0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000100000000000000000000000066293A9B1339CA99623E82BC71F88D767F60AD210000000000000000000000000000000000000000000000000000000000000323 ) => ( True )
      • GmStudioCatharsis.safeTransferFrom( from=0x17a6A2C0491a004F7b342362aF078396826c4fE7, to=0xB64FDc6c2044242E2823b0F7e251dc2Fd69cDbd2, tokenId=803 )
        • WyvernProxyRegistry.proxies( 0xB64FDc6c2044242E2823b0F7e251dc2Fd69cDbd2 ) => ( 0x740FF910420DCeE7853A09Ec9D28F4aF461b579e )
        • ETH 0.00525 FeeManagement.CALL( )
        • ETH 0.07875 DelegatedPaymentSplitter.CALL( )
          • ETH 0.07875 DelegatedPaymentSplitter.DELEGATECALL( )
          • ETH 0.966 0x17a6a2c0491a004f7b342362af078396826c4fe7.CALL( )
            File 1 of 8: TransparentUpgradeableProxy
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import "@openzeppelin/contracts/proxy/ERC1967/ERC1967Proxy.sol";
            import "@openzeppelin/contracts/proxy/transparent/TransparentUpgradeableProxy.sol";
            import "@openzeppelin/contracts/proxy/transparent/ProxyAdmin.sol";
            // Kept for backwards compatibility with older versions of Hardhat and Truffle plugins.
            contract AdminUpgradeabilityProxy is TransparentUpgradeableProxy {
                constructor(address logic, address admin, bytes memory data) payable TransparentUpgradeableProxy(logic, admin, data) {}
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import "../Proxy.sol";
            import "./ERC1967Upgrade.sol";
            /**
             * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
             * implementation address that can be changed. This address is stored in storage in the location specified by
             * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
             * implementation behind the proxy.
             */
            contract ERC1967Proxy is Proxy, ERC1967Upgrade {
                /**
                 * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                 *
                 * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                 * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                 */
                constructor(address _logic, bytes memory _data) payable {
                    assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                    _upgradeToAndCall(_logic, _data, false);
                }
                /**
                 * @dev Returns the current implementation address.
                 */
                function _implementation() internal view virtual override returns (address impl) {
                    return ERC1967Upgrade._getImplementation();
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import "../ERC1967/ERC1967Proxy.sol";
            /**
             * @dev This contract implements a proxy that is upgradeable by an admin.
             *
             * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
             * clashing], which can potentially be used in an attack, this contract uses the
             * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
             * things that go hand in hand:
             *
             * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
             * that call matches one of the admin functions exposed by the proxy itself.
             * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
             * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
             * "admin cannot fallback to proxy target".
             *
             * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
             * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
             * to sudden errors when trying to call a function from the proxy implementation.
             *
             * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
             * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
             */
            contract TransparentUpgradeableProxy is ERC1967Proxy {
                /**
                 * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                 * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
                 */
                constructor(address _logic, address admin_, bytes memory _data) payable ERC1967Proxy(_logic, _data) {
                    assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                    _changeAdmin(admin_);
                }
                /**
                 * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                 */
                modifier ifAdmin() {
                    if (msg.sender == _getAdmin()) {
                        _;
                    } else {
                        _fallback();
                    }
                }
                /**
                 * @dev Returns the current admin.
                 *
                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                 *
                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                 * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                 */
                function admin() external ifAdmin returns (address admin_) {
                    admin_ = _getAdmin();
                }
                /**
                 * @dev Returns the current implementation.
                 *
                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                 *
                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                 * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                 */
                function implementation() external ifAdmin returns (address implementation_) {
                    implementation_ = _implementation();
                }
                /**
                 * @dev Changes the admin of the proxy.
                 *
                 * Emits an {AdminChanged} event.
                 *
                 * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
                 */
                function changeAdmin(address newAdmin) external virtual ifAdmin {
                    _changeAdmin(newAdmin);
                }
                /**
                 * @dev Upgrade the implementation of the proxy.
                 *
                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                 */
                function upgradeTo(address newImplementation) external ifAdmin {
                    _upgradeToAndCall(newImplementation, bytes(""), false);
                }
                /**
                 * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                 * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                 * proxied contract.
                 *
                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                 */
                function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                    _upgradeToAndCall(newImplementation, data, true);
                }
                /**
                 * @dev Returns the current admin.
                 */
                function _admin() internal view virtual returns (address) {
                    return _getAdmin();
                }
                /**
                 * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                 */
                function _beforeFallback() internal virtual override {
                    require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                    super._beforeFallback();
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import "./TransparentUpgradeableProxy.sol";
            import "../../access/Ownable.sol";
            /**
             * @dev This is an auxiliary contract meant to be assigned as the admin of a {TransparentUpgradeableProxy}. For an
             * explanation of why you would want to use this see the documentation for {TransparentUpgradeableProxy}.
             */
            contract ProxyAdmin is Ownable {
                /**
                 * @dev Returns the current implementation of `proxy`.
                 *
                 * Requirements:
                 *
                 * - This contract must be the admin of `proxy`.
                 */
                function getProxyImplementation(TransparentUpgradeableProxy proxy) public view virtual returns (address) {
                    // We need to manually run the static call since the getter cannot be flagged as view
                    // bytes4(keccak256("implementation()")) == 0x5c60da1b
                    (bool success, bytes memory returndata) = address(proxy).staticcall(hex"5c60da1b");
                    require(success);
                    return abi.decode(returndata, (address));
                }
                /**
                 * @dev Returns the current admin of `proxy`.
                 *
                 * Requirements:
                 *
                 * - This contract must be the admin of `proxy`.
                 */
                function getProxyAdmin(TransparentUpgradeableProxy proxy) public view virtual returns (address) {
                    // We need to manually run the static call since the getter cannot be flagged as view
                    // bytes4(keccak256("admin()")) == 0xf851a440
                    (bool success, bytes memory returndata) = address(proxy).staticcall(hex"f851a440");
                    require(success);
                    return abi.decode(returndata, (address));
                }
                /**
                 * @dev Changes the admin of `proxy` to `newAdmin`.
                 *
                 * Requirements:
                 *
                 * - This contract must be the current admin of `proxy`.
                 */
                function changeProxyAdmin(TransparentUpgradeableProxy proxy, address newAdmin) public virtual onlyOwner {
                    proxy.changeAdmin(newAdmin);
                }
                /**
                 * @dev Upgrades `proxy` to `implementation`. See {TransparentUpgradeableProxy-upgradeTo}.
                 *
                 * Requirements:
                 *
                 * - This contract must be the admin of `proxy`.
                 */
                function upgrade(TransparentUpgradeableProxy proxy, address implementation) public virtual onlyOwner {
                    proxy.upgradeTo(implementation);
                }
                /**
                 * @dev Upgrades `proxy` to `implementation` and calls a function on the new implementation. See
                 * {TransparentUpgradeableProxy-upgradeToAndCall}.
                 *
                 * Requirements:
                 *
                 * - This contract must be the admin of `proxy`.
                 */
                function upgradeAndCall(TransparentUpgradeableProxy proxy, address implementation, bytes memory data) public payable virtual onlyOwner {
                    proxy.upgradeToAndCall{value: msg.value}(implementation, data);
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            /**
             * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
             * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
             * be specified by overriding the virtual {_implementation} function.
             *
             * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
             * different contract through the {_delegate} function.
             *
             * The success and return data of the delegated call will be returned back to the caller of the proxy.
             */
            abstract contract Proxy {
                /**
                 * @dev Delegates the current call to `implementation`.
                 *
                 * This function does not return to its internall call site, it will return directly to the external caller.
                 */
                function _delegate(address implementation) internal virtual {
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        // Copy msg.data. We take full control of memory in this inline assembly
                        // block because it will not return to Solidity code. We overwrite the
                        // Solidity scratch pad at memory position 0.
                        calldatacopy(0, 0, calldatasize())
                        // Call the implementation.
                        // out and outsize are 0 because we don't know the size yet.
                        let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                        // Copy the returned data.
                        returndatacopy(0, 0, returndatasize())
                        switch result
                        // delegatecall returns 0 on error.
                        case 0 { revert(0, returndatasize()) }
                        default { return(0, returndatasize()) }
                    }
                }
                /**
                 * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                 * and {_fallback} should delegate.
                 */
                function _implementation() internal view virtual returns (address);
                /**
                 * @dev Delegates the current call to the address returned by `_implementation()`.
                 *
                 * This function does not return to its internall call site, it will return directly to the external caller.
                 */
                function _fallback() internal virtual {
                    _beforeFallback();
                    _delegate(_implementation());
                }
                /**
                 * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                 * function in the contract matches the call data.
                 */
                fallback () external payable virtual {
                    _fallback();
                }
                /**
                 * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                 * is empty.
                 */
                receive () external payable virtual {
                    _fallback();
                }
                /**
                 * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                 * call, or as part of the Solidity `fallback` or `receive` functions.
                 *
                 * If overriden should call `super._beforeFallback()`.
                 */
                function _beforeFallback() internal virtual {
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.2;
            import "../beacon/IBeacon.sol";
            import "../../utils/Address.sol";
            import "../../utils/StorageSlot.sol";
            /**
             * @dev This abstract contract provides getters and event emitting update functions for
             * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
             *
             * _Available since v4.1._
             *
             * @custom:oz-upgrades-unsafe-allow delegatecall
             */
            abstract contract ERC1967Upgrade {
                // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
                bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
                /**
                 * @dev Storage slot with the address of the current implementation.
                 * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                 * validated in the constructor.
                 */
                bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                /**
                 * @dev Emitted when the implementation is upgraded.
                 */
                event Upgraded(address indexed implementation);
                /**
                 * @dev Returns the current implementation address.
                 */
                function _getImplementation() internal view returns (address) {
                    return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                }
                /**
                 * @dev Stores a new address in the EIP1967 implementation slot.
                 */
                function _setImplementation(address newImplementation) private {
                    require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                    StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                }
                /**
                 * @dev Perform implementation upgrade
                 *
                 * Emits an {Upgraded} event.
                 */
                function _upgradeTo(address newImplementation) internal {
                    _setImplementation(newImplementation);
                    emit Upgraded(newImplementation);
                }
                /**
                 * @dev Perform implementation upgrade with additional setup call.
                 *
                 * Emits an {Upgraded} event.
                 */
                function _upgradeToAndCall(address newImplementation, bytes memory data, bool forceCall) internal {
                    _setImplementation(newImplementation);
                    emit Upgraded(newImplementation);
                    if (data.length > 0 || forceCall) {
                        Address.functionDelegateCall(newImplementation, data);
                    }
                }
                /**
                 * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
                 *
                 * Emits an {Upgraded} event.
                 */
                function _upgradeToAndCallSecure(address newImplementation, bytes memory data, bool forceCall) internal {
                    address oldImplementation = _getImplementation();
                    // Initial upgrade and setup call
                    _setImplementation(newImplementation);
                    if (data.length > 0 || forceCall) {
                        Address.functionDelegateCall(newImplementation, data);
                    }
                    // Perform rollback test if not already in progress
                    StorageSlot.BooleanSlot storage rollbackTesting = StorageSlot.getBooleanSlot(_ROLLBACK_SLOT);
                    if (!rollbackTesting.value) {
                        // Trigger rollback using upgradeTo from the new implementation
                        rollbackTesting.value = true;
                        Address.functionDelegateCall(
                            newImplementation,
                            abi.encodeWithSignature(
                                "upgradeTo(address)",
                                oldImplementation
                            )
                        );
                        rollbackTesting.value = false;
                        // Check rollback was effective
                        require(oldImplementation == _getImplementation(), "ERC1967Upgrade: upgrade breaks further upgrades");
                        // Finally reset to the new implementation and log the upgrade
                        _setImplementation(newImplementation);
                        emit Upgraded(newImplementation);
                    }
                }
                /**
                 * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
                 * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
                 *
                 * Emits a {BeaconUpgraded} event.
                 */
                function _upgradeBeaconToAndCall(address newBeacon, bytes memory data, bool forceCall) internal {
                    _setBeacon(newBeacon);
                    emit BeaconUpgraded(newBeacon);
                    if (data.length > 0 || forceCall) {
                        Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
                    }
                }
                /**
                 * @dev Storage slot with the admin of the contract.
                 * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                 * validated in the constructor.
                 */
                bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                /**
                 * @dev Emitted when the admin account has changed.
                 */
                event AdminChanged(address previousAdmin, address newAdmin);
                /**
                 * @dev Returns the current admin.
                 */
                function _getAdmin() internal view returns (address) {
                    return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
                }
                /**
                 * @dev Stores a new address in the EIP1967 admin slot.
                 */
                function _setAdmin(address newAdmin) private {
                    require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                    StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
                }
                /**
                 * @dev Changes the admin of the proxy.
                 *
                 * Emits an {AdminChanged} event.
                 */
                function _changeAdmin(address newAdmin) internal {
                    emit AdminChanged(_getAdmin(), newAdmin);
                    _setAdmin(newAdmin);
                }
                /**
                 * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
                 * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
                 */
                bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
                /**
                 * @dev Emitted when the beacon is upgraded.
                 */
                event BeaconUpgraded(address indexed beacon);
                /**
                 * @dev Returns the current beacon.
                 */
                function _getBeacon() internal view returns (address) {
                    return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
                }
                /**
                 * @dev Stores a new beacon in the EIP1967 beacon slot.
                 */
                function _setBeacon(address newBeacon) private {
                    require(
                        Address.isContract(newBeacon),
                        "ERC1967: new beacon is not a contract"
                    );
                    require(
                        Address.isContract(IBeacon(newBeacon).implementation()),
                        "ERC1967: beacon implementation is not a contract"
                    );
                    StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            /**
             * @dev This is the interface that {BeaconProxy} expects of its beacon.
             */
            interface IBeacon {
                /**
                 * @dev Must return an address that can be used as a delegate call target.
                 *
                 * {BeaconProxy} will check that this address is a contract.
                 */
                function implementation() external view returns (address);
            }
            // SPDX-License-Identifier: MIT
            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;
                    // solhint-disable-next-line no-inline-assembly
                    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");
                    // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                    (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");
                    // solhint-disable-next-line avoid-low-level-calls
                    (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");
                    // solhint-disable-next-line avoid-low-level-calls
                    (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");
                    // solhint-disable-next-line avoid-low-level-calls
                    (bool success, bytes memory returndata) = target.delegatecall(data);
                    return _verifyCallResult(success, returndata, errorMessage);
                }
                function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                            // solhint-disable-next-line no-inline-assembly
                            assembly {
                                let returndata_size := mload(returndata)
                                revert(add(32, returndata), returndata_size)
                            }
                        } else {
                            revert(errorMessage);
                        }
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            /**
             * @dev Library for reading and writing primitive types to specific storage slots.
             *
             * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
             * This library helps with reading and writing to such slots without the need for inline assembly.
             *
             * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
             *
             * Example usage to set ERC1967 implementation slot:
             * ```
             * contract ERC1967 {
             *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
             *
             *     function _getImplementation() internal view returns (address) {
             *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
             *     }
             *
             *     function _setImplementation(address newImplementation) internal {
             *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
             *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
             *     }
             * }
             * ```
             *
             * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
             */
            library StorageSlot {
                struct AddressSlot {
                    address value;
                }
                struct BooleanSlot {
                    bool value;
                }
                struct Bytes32Slot {
                    bytes32 value;
                }
                struct Uint256Slot {
                    uint256 value;
                }
                /**
                 * @dev Returns an `AddressSlot` with member `value` located at `slot`.
                 */
                function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                    assembly {
                        r.slot := slot
                    }
                }
                /**
                 * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
                 */
                function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                    assembly {
                        r.slot := slot
                    }
                }
                /**
                 * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
                 */
                function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                    assembly {
                        r.slot := slot
                    }
                }
                /**
                 * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
                 */
                function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                    assembly {
                        r.slot := slot
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            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 () {
                    address msgSender = _msgSender();
                    _owner = msgSender;
                    emit OwnershipTransferred(address(0), 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 {
                    emit OwnershipTransferred(_owner, address(0));
                    _owner = 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");
                    emit OwnershipTransferred(_owner, newOwner);
                    _owner = newOwner;
                }
            }
            // SPDX-License-Identifier: MIT
            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) {
                    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                    return msg.data;
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import "../ERC1967/ERC1967Upgrade.sol";
            /**
             * @dev Base contract for building openzeppelin-upgrades compatible implementations for the {ERC1967Proxy}. It includes
             * publicly available upgrade functions that are called by the plugin and by the secure upgrade mechanism to verify
             * continuation of the upgradability.
             *
             * The {_authorizeUpgrade} function MUST be overridden to include access restriction to the upgrade mechanism.
             *
             * _Available since v4.1._
             */
            abstract contract UUPSUpgradeable is ERC1967Upgrade {
                function upgradeTo(address newImplementation) external virtual {
                    _authorizeUpgrade(newImplementation);
                    _upgradeToAndCallSecure(newImplementation, bytes(""), false);
                }
                function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual {
                    _authorizeUpgrade(newImplementation);
                    _upgradeToAndCallSecure(newImplementation, data, true);
                }
                function _authorizeUpgrade(address newImplementation) internal virtual;
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.2;
            import "@openzeppelin/contracts/proxy/utils/UUPSUpgradeable.sol";
            abstract contract Proxiable is UUPSUpgradeable {
                function _authorizeUpgrade(address newImplementation) internal override {
                    _beforeUpgrade(newImplementation);
                }
                function _beforeUpgrade(address newImplementation) internal virtual;
            }
            contract ChildOfProxiable is Proxiable {
                function _beforeUpgrade(address newImplementation) internal virtual override {}
            }
            

            File 2 of 8: GmStudioCatharsis
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2021 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            import "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
            import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
            /**
            @title SignatureChecker
            @notice Additional functions for EnumerableSet.Addresset that require a valid
            ECDSA signature of a standardized message, signed by any member of the set.
             */
            library SignatureChecker {
                using EnumerableSet for EnumerableSet.AddressSet;
                /**
                @notice Requires that the message has not been used previously and that the
                recovered signer is contained in the signers AddressSet.
                @dev Convenience wrapper for message generation + signature verification
                + marking message as used
                @param signers Set of addresses from which signatures are accepted.
                @param usedMessages Set of already-used messages.
                @param signature ECDSA signature of message.
                 */
                function requireValidSignature(
                    EnumerableSet.AddressSet storage signers,
                    bytes memory data,
                    bytes calldata signature,
                    mapping(bytes32 => bool) storage usedMessages
                ) internal {
                    bytes32 message = generateMessage(data);
                    require(
                        !usedMessages[message],
                        "SignatureChecker: Message already used"
                    );
                    usedMessages[message] = true;
                    requireValidSignature(signers, message, signature);
                }
                /**
                @notice Requires that the message has not been used previously and that the
                recovered signer is contained in the signers AddressSet.
                @dev Convenience wrapper for message generation + signature verification.
                 */
                function requireValidSignature(
                    EnumerableSet.AddressSet storage signers,
                    bytes memory data,
                    bytes calldata signature
                ) internal view {
                    bytes32 message = generateMessage(data);
                    requireValidSignature(signers, message, signature);
                }
                /**
                @notice Requires that the message has not been used previously and that the
                recovered signer is contained in the signers AddressSet.
                @dev Convenience wrapper for message generation from address +
                signature verification.
                 */
                function requireValidSignature(
                    EnumerableSet.AddressSet storage signers,
                    address a,
                    bytes calldata signature
                ) internal view {
                    bytes32 message = generateMessage(abi.encodePacked(a));
                    requireValidSignature(signers, message, signature);
                }
                /**
                @notice Common validator logic, checking if the recovered signer is
                contained in the signers AddressSet.
                */
                function validSignature(
                    EnumerableSet.AddressSet storage signers,
                    bytes32 message,
                    bytes calldata signature
                ) internal view returns (bool) {
                    return signers.contains(ECDSA.recover(message, signature));
                }
                /**
                @notice Requires that the recovered signer is contained in the signers
                AddressSet.
                @dev Convenience wrapper that reverts if the signature validation fails.
                */
                function requireValidSignature(
                    EnumerableSet.AddressSet storage signers,
                    bytes32 message,
                    bytes calldata signature
                ) internal view {
                    require(
                        validSignature(signers, message, signature),
                        "SignatureChecker: Invalid signature"
                    );
                }
                /**
                @notice Generates a message for a given data input that will be signed
                off-chain using ECDSA.
                @dev For multiple data fields, a standard concatenation using 
                `abi.encodePacked` is commonly used to build data.
                 */
                function generateMessage(bytes memory data)
                    internal
                    pure
                    returns (bytes32)
                {
                    return ECDSA.toEthSignedMessageHash(data);
                }
            }
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2022 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            import "./ERC721APreApproval.sol";
            import "../utils/OwnerPausable.sol";
            /**
            @notice An ERC721A contract with common functionality:
             - OpenSea gas-free listings
             - Pausable with toggling functions exposed to Owner only
             */
            contract ERC721ACommon is ERC721APreApproval, OwnerPausable {
                constructor(string memory name, string memory symbol)
                    ERC721A(name, symbol)
                {} // solhint-disable-line no-empty-blocks
                /// @notice Requires that the token exists.
                modifier tokenExists(uint256 tokenId) {
                    require(ERC721A._exists(tokenId), "ERC721ACommon: Token doesn't exist");
                    _;
                }
                /// @notice Requires that msg.sender owns or is approved for the token.
                modifier onlyApprovedOrOwner(uint256 tokenId) {
                    require(
                        _ownershipOf(tokenId).addr == _msgSender() ||
                            getApproved(tokenId) == _msgSender(),
                        "ERC721ACommon: Not approved nor owner"
                    );
                    _;
                }
                function _beforeTokenTransfers(
                    address from,
                    address to,
                    uint256 startTokenId,
                    uint256 quantity
                ) internal virtual override {
                    require(!paused(), "ERC721ACommon: paused");
                    super._beforeTokenTransfers(from, to, startTokenId, quantity);
                }
                /// @notice Overrides supportsInterface as required by inheritance.
                function supportsInterface(bytes4 interfaceId)
                    public
                    view
                    virtual
                    override(ERC721A)
                    returns (bool)
                {
                    return super.supportsInterface(interfaceId);
                }
            }
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2021 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            import "@openzeppelin/contracts/utils/Context.sol";
            import "../thirdparty/opensea/OpenSeaGasFreeListing.sol";
            import "erc721a/contracts/ERC721A.sol";
            /// @notice Pre-approval of OpenSea proxies for gas-less listing
            /// @dev This wrapper allows users to revoke the pre-approval of their
            /// associated proxy and emits the corresponding events. This is necessary for
            /// external tools to index approvals correctly and inform the user.
            /// @dev The pre-approval is triggered on a per-wallet basis during the first
            /// transfer transactions. It will only be enabled for wallets with an existing
            /// proxy. Not having a proxy incurs a gas overhead.
            /// @dev This wrapper optimizes for the following scenario:
            /// - The majority of users already have a wyvern proxy
            /// - Most of them want to transfer tokens via wyvern exchanges
            abstract contract ERC721APreApproval is ERC721A, Context {
                /// @dev It is important that Active remains at first position, since this
                /// is the scenario that we are trying to optimize for.
                enum State {
                    Active,
                    Inactive
                }
                /// @notice The state of the pre-approval for a given owner
                mapping(address => State) private state;
                /// @dev Returns true if either standard `isApprovedForAll()` or if the
                /// `operator` is the OpenSea proxy for the `owner` provided the
                /// pre-approval is active.
                function isApprovedForAll(address owner, address operator)
                    public
                    view
                    virtual
                    override
                    returns (bool)
                {
                    if (super.isApprovedForAll(owner, operator)) {
                        return true;
                    }
                    return
                        state[owner] == State.Active &&
                        OpenSeaGasFreeListing.isApprovedForAll(owner, operator);
                }
                /// @dev Uses the standard `setApprovalForAll` or toggles the pre-approval
                /// state if `operator` is the OpenSea proxy for the sender.
                function setApprovalForAll(address operator, bool approved)
                    public
                    virtual
                    override
                {
                    address owner = _msgSender();
                    if (operator == OpenSeaGasFreeListing.proxyFor(owner)) {
                        state[owner] = approved ? State.Active : State.Inactive;
                        emit ApprovalForAll(owner, operator, approved);
                    } else {
                        super.setApprovalForAll(operator, approved);
                    }
                }
                /// @dev Checks if the receiver has an existing proxy. If not, the
                /// pre-approval is disabled.
                function _beforeTokenTransfers(
                    address from,
                    address to,
                    uint256 startTokenId,
                    uint256 quantity
                ) internal virtual override {
                    super._beforeTokenTransfers(from, to, startTokenId, quantity);
                    // Exclude burns and inactive pre-approvals
                    if (to == address(0) || state[to] == State.Inactive) {
                        return;
                    }
                    address operator = OpenSeaGasFreeListing.proxyFor(to);
                    // Disable if `to` has no proxy
                    if (operator == address(0)) {
                        state[to] = State.Inactive;
                        return;
                    }
                    // Avoid emitting unnecessary events.
                    if (balanceOf(to) == 0) {
                        emit ApprovalForAll(to, operator, true);
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2021 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            interface IPaymentSplitterFactory {
                /// @notice Deploys a minimal contract proxy to a PaymentSplitter.
                function deploy(address[] memory payees, uint256[] memory shares)
                    external
                    returns (address);
                /**
                @notice Deploys a minimal contract proxy to a PaymentSplitter, at a
                deterministic address.
                @dev Use predictDeploymentAddress() with the same salt to predit the address
                before calling deployDeterministic(). See OpenZeppelin's proxy/Clones.sol
                for details and caveats, primarily that this will revert if a salt is
                reused.
                 */
                function deployDeterministic(
                    bytes32 salt,
                    address[] memory payees,
                    uint256[] memory shares
                ) external returns (address);
                /**
                @notice Returns the address at which a new PaymentSplitter will be deployed
                if using the same salt as passed to this function.
                 */
                function predictDeploymentAddress(bytes32 salt)
                    external
                    view
                    returns (address);
            }
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2021 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            import "./IPaymentSplitterFactory.sol";
            /**
            @notice Convenience library for using ethier's PaymentSplitterFactory for cheap
            deployment of OpenZeppelin PaymentSplitters via minimal proxy contracts. A
            single factory contract is deployed on supported chains, the respective
            addresses of which are determined via the chainid() and returned by this
            library's instance() function.
             */
            library PaymentSplitterDeployer {
                /***
                @notice Returns the ethier PaymentSplitterFactory instance for the current
                chain.
                 */
                function instance() internal view returns (IPaymentSplitterFactory) {
                    address factory;
                    assembly {
                        switch chainid()
                        case 1 {
                            // mainnet
                            factory := 0xf034d6a4b1a64f0e6038632d87746ca24b79d325
                        }
                        case 4 {
                            // Rinkeby
                            factory := 0x633dc916D9f59cf4aA117dE2Bb8edF7752270EC0
                        }
                        case 1337 {
                            // The geth SimulatedBackend iff used with the ethier
                            // factorytest package.
                            factory := 0xa516d2c64ED7Fe2004A93Bc123854B229F3Bb738
                        }
                    }
                    require(
                        factory != address(0),
                        "PaymentSplitterFactory: not deployed on current chain"
                    );
                    return IPaymentSplitterFactory(factory);
                }
            }
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2021 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            // Inspired by BaseOpenSea by Simon Fremaux (@dievardump) but without the need
            // to pass specific addresses depending on deployment network.
            // https://gist.github.com/dievardump/483eb43bc6ed30b14f01e01842e3339b/
            import "./ProxyRegistry.sol";
            /// @notice Library to achieve gas-free listings on OpenSea.
            library OpenSeaGasFreeListing {
                /**
                @notice Returns whether the operator is an OpenSea proxy for the owner, thus
                allowing it to list without the token owner paying gas.
                @dev ERC{721,1155}.isApprovedForAll should be overriden to also check if
                this function returns true.
                 */
                function isApprovedForAll(address owner, address operator)
                    internal
                    view
                    returns (bool)
                {
                    address proxy = proxyFor(owner);
                    return proxy != address(0) && proxy == operator;
                }
                /**
                @notice Returns the OpenSea proxy address for the owner.
                 */
                function proxyFor(address owner) internal view returns (address) {
                    address registry;
                    uint256 chainId;
                    assembly {
                        chainId := chainid()
                        switch chainId
                        // Production networks are placed higher to minimise the number of
                        // checks performed and therefore reduce gas. By the same rationale,
                        // mainnet comes before Polygon as it's more expensive.
                        case 1 {
                            // mainnet
                            registry := 0xa5409ec958c83c3f309868babaca7c86dcb077c1
                        }
                        case 137 {
                            // polygon
                            registry := 0x58807baD0B376efc12F5AD86aAc70E78ed67deaE
                        }
                        case 4 {
                            // rinkeby
                            registry := 0xf57b2c51ded3a29e6891aba85459d600256cf317
                        }
                        case 80001 {
                            // mumbai
                            registry := 0xff7Ca10aF37178BdD056628eF42fD7F799fAc77c
                        }
                        case 1337 {
                            // The geth SimulatedBackend iff used with the ethier
                            // openseatest package. This is mocked as a Wyvern proxy as it's
                            // more complex than the 0x ones.
                            registry := 0xE1a2bbc877b29ADBC56D2659DBcb0ae14ee62071
                        }
                    }
                    // Unlike Wyvern, the registry itself is the proxy for all owners on 0x
                    // chains.
                    if (registry == address(0) || chainId == 137 || chainId == 80001) {
                        return registry;
                    }
                    return address(ProxyRegistry(registry).proxies(owner));
                }
            }
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2021 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            /// @notice A minimal interface describing OpenSea's Wyvern proxy registry.
            contract ProxyRegistry {
                mapping(address => OwnableDelegateProxy) public proxies;
            }
            /**
            @dev This pattern of using an empty contract is cargo-culted directly from
            OpenSea's example code. TODO: it's likely that the above mapping can be changed
            to address => address without affecting anything, but further investigation is
            needed (i.e. is there a subtle reason that OpenSea released it like this?).
             */
            // solhint-disable-next-line no-empty-blocks
            contract OwnableDelegateProxy {
            }
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2021 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            import "@openzeppelin/contracts/access/Ownable.sol";
            import "@openzeppelin/contracts/security/Pausable.sol";
            /// @notice A Pausable contract that can only be toggled by the Owner.
            contract OwnerPausable is Ownable, Pausable {
                /// @notice Pauses the contract.
                function pause() public onlyOwner {
                    Pausable._pause();
                }
                /// @notice Unpauses the contract.
                function unpause() public onlyOwner {
                    Pausable._unpause();
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.0 (access/Ownable.sol)
            pragma solidity ^0.8.0;
            import "../utils/Context.sol";
            /**
             * @dev Contract module which provides a basic access control mechanism, where
             * there is an account (an owner) that can be granted exclusive access to
             * specific functions.
             *
             * By default, the owner account will be the one that deploys the contract. This
             * can later be changed with {transferOwnership}.
             *
             * This module is used through inheritance. It will make available the modifier
             * `onlyOwner`, which can be applied to your functions to restrict their use to
             * the owner.
             */
            abstract contract Ownable is Context {
                address private _owner;
                event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                /**
                 * @dev Initializes the contract setting the deployer as the initial owner.
                 */
                constructor() {
                    _transferOwnership(_msgSender());
                }
                /**
                 * @dev 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 v4.4.0 (security/Pausable.sol)
            pragma solidity ^0.8.0;
            import "../utils/Context.sol";
            /**
             * @dev Contract module which allows children to implement an emergency stop
             * mechanism that can be triggered by an authorized account.
             *
             * This module is used through inheritance. It will make available the
             * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
             * the functions of your contract. Note that they will not be pausable by
             * simply including this module, only once the modifiers are put in place.
             */
            abstract contract Pausable is Context {
                /**
                 * @dev Emitted when the pause is triggered by `account`.
                 */
                event Paused(address account);
                /**
                 * @dev Emitted when the pause is lifted by `account`.
                 */
                event Unpaused(address account);
                bool private _paused;
                /**
                 * @dev Initializes the contract in unpaused state.
                 */
                constructor() {
                    _paused = false;
                }
                /**
                 * @dev Returns true if the contract is paused, and false otherwise.
                 */
                function paused() public view virtual returns (bool) {
                    return _paused;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is not paused.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                modifier whenNotPaused() {
                    require(!paused(), "Pausable: paused");
                    _;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is paused.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                modifier whenPaused() {
                    require(paused(), "Pausable: not paused");
                    _;
                }
                /**
                 * @dev Triggers stopped state.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                function _pause() internal virtual whenNotPaused {
                    _paused = true;
                    emit Paused(_msgSender());
                }
                /**
                 * @dev Returns to normal state.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                function _unpause() internal virtual whenPaused {
                    _paused = false;
                    emit Unpaused(_msgSender());
                }
            }
            // 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);
                        }
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.0 (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 v4.4.0 (utils/Strings.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev String operations.
             */
            library Strings {
                bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                /**
                 * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                 */
                function toString(uint256 value) internal pure returns (string memory) {
                    // Inspired by OraclizeAPI's implementation - MIT licence
                    // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                    if (value == 0) {
                        return "0";
                    }
                    uint256 temp = value;
                    uint256 digits;
                    while (temp != 0) {
                        digits++;
                        temp /= 10;
                    }
                    bytes memory buffer = new bytes(digits);
                    while (value != 0) {
                        digits -= 1;
                        buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                        value /= 10;
                    }
                    return string(buffer);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                 */
                function toHexString(uint256 value) internal pure returns (string memory) {
                    if (value == 0) {
                        return "0x00";
                    }
                    uint256 temp = value;
                    uint256 length = 0;
                    while (temp != 0) {
                        length++;
                        temp >>= 8;
                    }
                    return toHexString(value, length);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                 */
                function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                    bytes memory buffer = new bytes(2 * length + 2);
                    buffer[0] = "0";
                    buffer[1] = "x";
                    for (uint256 i = 2 * length + 1; i > 1; --i) {
                        buffer[i] = _HEX_SYMBOLS[value & 0xf];
                        value >>= 4;
                    }
                    require(value == 0, "Strings: hex length insufficient");
                    return string(buffer);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.0 (utils/cryptography/ECDSA.sol)
            pragma solidity ^0.8.0;
            import "../Strings.sol";
            /**
             * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
             *
             * These functions can be used to verify that a message was signed by the holder
             * of the private keys of a given address.
             */
            library ECDSA {
                enum RecoverError {
                    NoError,
                    InvalidSignature,
                    InvalidSignatureLength,
                    InvalidSignatureS,
                    InvalidSignatureV
                }
                function _throwError(RecoverError error) private pure {
                    if (error == RecoverError.NoError) {
                        return; // no error: do nothing
                    } else if (error == RecoverError.InvalidSignature) {
                        revert("ECDSA: invalid signature");
                    } else if (error == RecoverError.InvalidSignatureLength) {
                        revert("ECDSA: invalid signature length");
                    } else if (error == RecoverError.InvalidSignatureS) {
                        revert("ECDSA: invalid signature 's' value");
                    } else if (error == RecoverError.InvalidSignatureV) {
                        revert("ECDSA: invalid signature 'v' value");
                    }
                }
                /**
                 * @dev Returns the address that signed a hashed message (`hash`) with
                 * `signature` or error string. This address can then be used for verification purposes.
                 *
                 * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
                 * this function rejects them by requiring the `s` value to be in the lower
                 * half order, and the `v` value to be either 27 or 28.
                 *
                 * IMPORTANT: `hash` _must_ be the result of a hash operation for the
                 * verification to be secure: it is possible to craft signatures that
                 * recover to arbitrary addresses for non-hashed data. A safe way to ensure
                 * this is by receiving a hash of the original message (which may otherwise
                 * be too long), and then calling {toEthSignedMessageHash} on it.
                 *
                 * Documentation for signature generation:
                 * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
                 * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
                 *
                 * _Available since v4.3._
                 */
                function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
                    // Check the signature length
                    // - case 65: r,s,v signature (standard)
                    // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
                    if (signature.length == 65) {
                        bytes32 r;
                        bytes32 s;
                        uint8 v;
                        // ecrecover takes the signature parameters, and the only way to get them
                        // currently is to use assembly.
                        assembly {
                            r := mload(add(signature, 0x20))
                            s := mload(add(signature, 0x40))
                            v := byte(0, mload(add(signature, 0x60)))
                        }
                        return tryRecover(hash, v, r, s);
                    } else if (signature.length == 64) {
                        bytes32 r;
                        bytes32 vs;
                        // ecrecover takes the signature parameters, and the only way to get them
                        // currently is to use assembly.
                        assembly {
                            r := mload(add(signature, 0x20))
                            vs := mload(add(signature, 0x40))
                        }
                        return tryRecover(hash, r, vs);
                    } else {
                        return (address(0), RecoverError.InvalidSignatureLength);
                    }
                }
                /**
                 * @dev Returns the address that signed a hashed message (`hash`) with
                 * `signature`. This address can then be used for verification purposes.
                 *
                 * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
                 * this function rejects them by requiring the `s` value to be in the lower
                 * half order, and the `v` value to be either 27 or 28.
                 *
                 * IMPORTANT: `hash` _must_ be the result of a hash operation for the
                 * verification to be secure: it is possible to craft signatures that
                 * recover to arbitrary addresses for non-hashed data. A safe way to ensure
                 * this is by receiving a hash of the original message (which may otherwise
                 * be too long), and then calling {toEthSignedMessageHash} on it.
                 */
                function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
                    (address recovered, RecoverError error) = tryRecover(hash, signature);
                    _throwError(error);
                    return recovered;
                }
                /**
                 * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
                 *
                 * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
                 *
                 * _Available since v4.3._
                 */
                function tryRecover(
                    bytes32 hash,
                    bytes32 r,
                    bytes32 vs
                ) internal pure returns (address, RecoverError) {
                    bytes32 s;
                    uint8 v;
                    assembly {
                        s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                        v := add(shr(255, vs), 27)
                    }
                    return tryRecover(hash, v, r, s);
                }
                /**
                 * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
                 *
                 * _Available since v4.2._
                 */
                function recover(
                    bytes32 hash,
                    bytes32 r,
                    bytes32 vs
                ) internal pure returns (address) {
                    (address recovered, RecoverError error) = tryRecover(hash, r, vs);
                    _throwError(error);
                    return recovered;
                }
                /**
                 * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
                 * `r` and `s` signature fields separately.
                 *
                 * _Available since v4.3._
                 */
                function tryRecover(
                    bytes32 hash,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) internal pure returns (address, RecoverError) {
                    // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                    // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                    // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
                    // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                    //
                    // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                    // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                    // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                    // these malleable signatures as well.
                    if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
                        return (address(0), RecoverError.InvalidSignatureS);
                    }
                    if (v != 27 && v != 28) {
                        return (address(0), RecoverError.InvalidSignatureV);
                    }
                    // If the signature is valid (and not malleable), return the signer address
                    address signer = ecrecover(hash, v, r, s);
                    if (signer == address(0)) {
                        return (address(0), RecoverError.InvalidSignature);
                    }
                    return (signer, RecoverError.NoError);
                }
                /**
                 * @dev Overload of {ECDSA-recover} that receives the `v`,
                 * `r` and `s` signature fields separately.
                 */
                function recover(
                    bytes32 hash,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) internal pure returns (address) {
                    (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
                    _throwError(error);
                    return recovered;
                }
                /**
                 * @dev Returns an Ethereum Signed Message, created from a `hash`. This
                 * produces hash corresponding to the one signed with the
                 * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
                 * JSON-RPC method as part of EIP-191.
                 *
                 * See {recover}.
                 */
                function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
                    // 32 is the length in bytes of hash,
                    // enforced by the type signature above
                    return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
            32", hash));
                }
                /**
                 * @dev Returns an Ethereum Signed Message, created from `s`. This
                 * produces hash corresponding to the one signed with the
                 * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
                 * JSON-RPC method as part of EIP-191.
                 *
                 * See {recover}.
                 */
                function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
                    return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
            ", Strings.toString(s.length), s));
                }
                /**
                 * @dev Returns an Ethereum Signed Typed Data, created from a
                 * `domainSeparator` and a `structHash`. This produces hash corresponding
                 * to the one signed with the
                 * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
                 * JSON-RPC method as part of EIP-712.
                 *
                 * See {recover}.
                 */
                function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
                    return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.0 (utils/introspection/ERC165.sol)
            pragma solidity ^0.8.0;
            import "./IERC165.sol";
            /**
             * @dev Implementation of the {IERC165} interface.
             *
             * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
             * for the additional interface id that will be supported. For example:
             *
             * ```solidity
             * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
             *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
             * }
             * ```
             *
             * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
             */
            abstract contract ERC165 is IERC165 {
                /**
                 * @dev See {IERC165-supportsInterface}.
                 */
                function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                    return interfaceId == type(IERC165).interfaceId;
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.0 (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
            // OpenZeppelin Contracts v4.4.0 (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: UNLICENSED
            // Copyright (c) 2022 gmDAO
            pragma solidity >=0.8.0 <0.9.0;
            import "@openzeppelin/contracts/utils/Strings.sol";
            import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
            import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
            import "@openzeppelin/contracts/utils/Address.sol";
            import "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
            import "@divergencetech/ethier/contracts/erc721/ERC721ACommon.sol";
            import "@divergencetech/ethier/contracts/crypto/SignatureChecker.sol";
            import "@divergencetech/ethier/contracts/factories/PaymentSplitterDeployer.sol";
            import "../../utils/ERC2981SinglePercentual.sol";
            //                                           __                    __ __
            //                                          |  \\                  |  \\  \\
            //   ______  ______ ____           _______ _| ▓▓_   __    __  ____| ▓▓\\▓▓ ______
            //  /      \\|      \\    \\         /       \\   ▓▓ \\ |  \\  |  \\/      ▓▓  \\/      \\
            // |  ▓▓▓▓▓▓\\ ▓▓▓▓▓▓\\▓▓▓▓\\       |  ▓▓▓▓▓▓▓\\▓▓▓▓▓▓ | ▓▓  | ▓▓  ▓▓▓▓▓▓▓ ▓▓  ▓▓▓▓▓▓\\
            // | ▓▓  | ▓▓ ▓▓ | ▓▓ | ▓▓        \\▓▓    \\  | ▓▓ __| ▓▓  | ▓▓ ▓▓  | ▓▓ ▓▓ ▓▓  | ▓▓
            // | ▓▓__| ▓▓ ▓▓ | ▓▓ | ▓▓__      _\\▓▓▓▓▓▓\\ | ▓▓|  \\ ▓▓__/ ▓▓ ▓▓__| ▓▓ ▓▓ ▓▓__/ ▓▓
            //  \\▓▓    ▓▓ ▓▓ | ▓▓ | ▓▓  \\    |       ▓▓  \\▓▓  ▓▓\\▓▓    ▓▓\\▓▓    ▓▓ ▓▓\\▓▓    ▓▓
            //  _\\▓▓▓▓▓▓▓\\▓▓  \\▓▓  \\▓▓\\▓▓     \\▓▓▓▓▓▓▓    \\▓▓▓▓  \\▓▓▓▓▓▓  \\▓▓▓▓▓▓▓\\▓▓ \\▓▓▓▓▓▓
            // |  \\__| ▓▓
            //  \\▓▓    ▓▓
            //   \\▓▓▓▓▓▓
            //
            contract GmStudioCatharsis is
                ERC721ACommon,
                ReentrancyGuard,
                ERC2981SinglePercentual
            {
                using EnumerableSet for EnumerableSet.AddressSet;
                using SignatureChecker for EnumerableSet.AddressSet;
                using Address for address payable;
                /// @notice Price for minting
                uint256 public constant MINT_PRICE = 0.15 ether;
                /// @notice Splits payments between the Studio and the artist.
                address payable public immutable paymentSplitter;
                /// @notice Splits payments between the Studio and the artist.
                address payable public immutable paymentSplitterRoyalties;
                /// @notice Total maximum amount of tokens
                uint32 public constant MAX_NUM_TOKENS = 999;
                /// @notice Number of mints throught the early access minting interface.
                uint32 internal constant NUM_EARLY_ACCESS_MINTS = 999;
                /// @notice Number of mints for reserved the studio/artist.
                uint32 internal constant NUM_RESERVED_MINTS = 6;
                /// @notice Locks the mintReserve function
                bool internal reserveMinted;
                /// @notice Timestamps to enables/eisables minting interfaces
                /// @dev The following order is assumed
                /// signedMintOpeningTimestamp < publicMintOpeningTimestamp < mintClosingTimestamp
                struct MintConfig {
                    uint64 signedMintOpeningTimestamp;
                    uint64 publicMintOpeningTimestamp;
                    uint64 mintClosingTimestamp;
                }
                /// @notice The minting configuration
                MintConfig public mintConfig;
                /// @notice Stores the number of tokens minted from a signature during the
                /// early access stage.
                /// @dev Used in `mintEarlyAccess`
                mapping(bytes32 => uint256) public numEarlyAccessMintsFrom;
                /// @notice Stores the number of tokens minted from a signature during the
                /// public minting stage.
                /// @dev Used in `mintPublic`
                mapping(bytes32 => uint256) private _numPublicMintsFrom;
                /// @notice Signature signers for the early access stage.
                /// @dev Removing signers invalidates the corresponding signatures.
                EnumerableSet.AddressSet private _signersEarlyAccess;
                /// @notice Signature signers for the early access stage.
                /// @dev Removing signers invalidates the corresponding signatures.
                EnumerableSet.AddressSet private _signersPublic;
                /// @notice tokenURI() base path.
                /// @dev Without trailing slash
                string internal _baseTokenURI;
                constructor(
                    address newOwner,
                    address signerEarlyAccess,
                    address signerPublic,
                    string memory baseTokenURI,
                    MintConfig memory config,
                    address[] memory payees,
                    uint256[] memory shares,
                    uint256[] memory sharesRoyalties
                ) ERC721ACommon("Catharsis by Dario Lanza", "CATAR") {
                    _signersEarlyAccess.add(signerEarlyAccess);
                    _signersPublic.add(signerPublic);
                    _baseTokenURI = baseTokenURI;
                    mintConfig = config;
                    paymentSplitter = payable(
                        PaymentSplitterDeployer.instance().deploy(payees, shares)
                    );
                    paymentSplitterRoyalties = payable(
                        PaymentSplitterDeployer.instance().deploy(payees, sharesRoyalties)
                    );
                    _setRoyaltyPercentage(750);
                    _setRoyaltyReceiver(paymentSplitterRoyalties);
                    transferOwnership(newOwner);
                }
                // -------------------------------------------------------------------------
                //
                //  Minting
                //
                // -------------------------------------------------------------------------
                /// @notice Toggle minting relevant flags.
                function setMintConfig(MintConfig calldata config) external onlyOwner {
                    mintConfig = config;
                }
                /* solhint-disable not-rely-on-time */
                /// @dev Reverts if we are not in the early access minting window or the if
                /// `mintConfig` has not been set yet.
                modifier onlyDuringEarlyAccessMintingPeriod() {
                    if (
                        // solhint-disable-next-line not-rely-on-time
                        block.timestamp < mintConfig.signedMintOpeningTimestamp ||
                        block.timestamp > mintConfig.publicMintOpeningTimestamp
                    ) revert MintDisabled();
                    _;
                }
                /// @dev Reverts if we are not in the public minting window or the if
                /// `mintConfig` has not been set yet.
                modifier onlyDuringPublicMintingPeriod() {
                    if (
                        block.timestamp < mintConfig.publicMintOpeningTimestamp ||
                        block.timestamp > mintConfig.mintClosingTimestamp
                    ) revert MintDisabled();
                    _;
                }
                /* solhint-enable not-rely-on-time */
                /// @dev Reverts if called by a contract.
                modifier onlyEOA() {
                    /* solhint-disable-next-line avoid-tx-origin */
                    if (tx.origin != msg.sender) {
                        revert OnlyEOA();
                    }
                    _;
                }
                /// @notice Mints tokens to a given address using a signed message.
                /// @dev The minter might be different than the receiver.
                /// @param to Token receiver
                /// @param num Number of tokens to be minted.
                /// @param numMax Max number of tokens that can be minted to the receiver.
                /// @param nonce additional signature salt.
                /// @param signature to prove that the receiver is allowed to get mints.
                /// @dev The signed messages is generated by concatenating
                /// `address(this) || to || numMax || nonce`.
                function _mintSigned(
                    address to,
                    uint16 num,
                    uint16 numMax,
                    uint128 nonce,
                    bytes calldata signature,
                    EnumerableSet.AddressSet storage signers,
                    mapping(bytes32 => uint256) storage numMintedFrom
                ) internal {
                    // General checks
                    if (num * MINT_PRICE != msg.value) revert InvalidPayment();
                    // Signature related checks
                    bytes32 message = ECDSA.toEthSignedMessageHash(
                        abi.encodePacked(address(this), to, numMax, nonce)
                    );
                    if (num + numMintedFrom[message] > numMax)
                        revert TooManyMintsRequested();
                    signers.requireValidSignature(message, signature);
                    numMintedFrom[message] += num;
                    _processPayment();
                    _processMint(to, num);
                }
                /// @notice Mints tokens to a given address using a signed message during
                /// the early access stage.
                /// @dev The minter might be different than the receiver.
                /// @param to Token receiver
                /// @param num Number of tokens to be minted.
                /// @param numMax Max number of tokens that can be minted to the receiver.
                /// @param nonce additional signature salt.
                /// @param signature to prove that the receiver is allowed to get mints.
                function mintEarlyAccess(
                    address to,
                    uint16 num,
                    uint16 numMax,
                    uint128 nonce,
                    bytes calldata signature
                ) external payable onlyDuringEarlyAccessMintingPeriod nonReentrant {
                    if (num > _numEarlyAccessMintsRemaining())
                        revert InsufficientTokensRemanining();
                    _mintSigned(
                        to,
                        num,
                        numMax,
                        nonce,
                        signature,
                        _signersEarlyAccess,
                        numEarlyAccessMintsFrom
                    );
                }
                /// @notice Computes the number of remaining early access mints.
                /// @dev This takes into account whether or not the reserve was alredy minted.
                function _numEarlyAccessMintsRemaining() internal view returns (uint256) {
                    uint256 maxMints = reserveMinted
                        ? NUM_EARLY_ACCESS_MINTS + NUM_RESERVED_MINTS
                        : NUM_EARLY_ACCESS_MINTS;
                    return maxMints - totalSupply();
                }
                /// @notice Mints tokens for the sender using a signed message during
                /// the public minting stage.
                /// @param num Number of tokens to be minted.
                /// @param numMax Max number of tokens that can be minted.
                /// @param nonce additional signature salt.
                /// @param signature to prove that the receiver is allowed to get mints.
                function mintPublic(
                    uint16 num,
                    uint16 numMax,
                    uint128 nonce,
                    bytes calldata signature
                ) external payable onlyDuringPublicMintingPeriod onlyEOA {
                    _mintSigned(
                        msg.sender,
                        num,
                        numMax,
                        nonce,
                        signature,
                        _signersPublic,
                        _numPublicMintsFrom
                    );
                }
                /// @notice Receiver of reserve mints.
                /// @dev `to` corresponds to the address of the receiver and `num` to the
                /// number of tokens to be minted.
                struct ReserveReceiver {
                    address to;
                    uint32 num;
                }
                /// @notice Mints the initial token reserve.
                /// @param receivers Array of token receivers
                /// @dev The minter might be different than the receiver.
                /// @dev Reverts if the number of minted tokens does not equal
                /// NUM_RESERVED_MINTS
                function mintReserve(ReserveReceiver[] calldata receivers)
                    external
                    onlyOwner
                {
                    if (reserveMinted) revert MintDisabled();
                    reserveMinted = true;
                    uint256 numReceivers = receivers.length;
                    uint256 minted = 0;
                    for (uint256 idx = 0; idx < numReceivers; ++idx) {
                        minted += receivers[idx].num;
                        _processMint(receivers[idx].to, receivers[idx].num);
                    }
                    if (minted != NUM_RESERVED_MINTS) revert WrongNumberOfReserveMints();
                }
                /// @notice Mints new tokens for the recipient.
                function _processMint(address to, uint256 num) internal {
                    if (totalSupply() + num > MAX_NUM_TOKENS)
                        revert InsufficientTokensRemanining();
                    _mint(to, num);
                }
                /// @notice Computes a pseudorandom seed for a mint batch.
                /// @dev Even though this process can be gamed in principle, it is extremly
                /// difficult to do so in practise. Therefore we can still rely on this to
                /// derive fair seeds.
                function _computeBatchSeed(address to) private view returns (uint24) {
                    return
                        uint24(
                            bytes3(
                                keccak256(
                                    abi.encodePacked(
                                        block.timestamp,
                                        block.difficulty,
                                        blockhash(block.number - 1),
                                        to
                                    )
                                )
                            )
                        );
                }
                /// @dev Sets the extra data field during token transfers
                function _extraData(
                    address from,
                    address to,
                    uint24 previousExtraData
                ) internal view virtual override returns (uint24) {
                    // if minting, compute a batch seed
                    if (from == address(0)) {
                        return _computeBatchSeed(to);
                    }
                    // else return the current value
                    return previousExtraData;
                }
                // -------------------------------------------------------------------------
                //
                //  Signature validataion
                //
                // -------------------------------------------------------------------------
                /// @notice The different minting stages
                enum MintingStage {
                    EarlyAccess,
                    Public
                }
                /// @notice Helper function the retrieves the correct set of signers for
                /// a given minting stage.
                function _getSigners(MintingStage stage)
                    internal
                    view
                    returns (EnumerableSet.AddressSet storage)
                {
                    if (stage == MintingStage.EarlyAccess) return _signersEarlyAccess;
                    if (stage == MintingStage.Public) return _signersPublic;
                    revert WrongMintingStage();
                }
                /// @notice Removes and adds addresses to the set of allowed signers.
                /// @dev Removal is performed before addition.
                function changeSigners(
                    MintingStage stage,
                    address[] calldata delSigners,
                    address[] calldata addSigners
                ) external onlyOwner {
                    EnumerableSet.AddressSet storage _signers = _getSigners(stage);
                    for (uint256 idx; idx < delSigners.length; ++idx) {
                        _signers.remove(delSigners[idx]);
                    }
                    for (uint256 idx; idx < addSigners.length; ++idx) {
                        _signers.add(addSigners[idx]);
                    }
                }
                /// @notice Returns the addresses that are used for signature verification
                /// for a given minting stage.
                function getSigners(MintingStage stage)
                    external
                    view
                    returns (address[] memory signers)
                {
                    EnumerableSet.AddressSet storage _signers = _getSigners(stage);
                    uint256 len = _signers.length();
                    signers = new address[](len);
                    for (uint256 idx = 0; idx < len; ++idx) {
                        signers[idx] = _signers.at(idx);
                    }
                }
                // -------------------------------------------------------------------------
                //
                //  Payment
                //
                // -------------------------------------------------------------------------
                /// @notice Processes an incoming payment and sends it to the payment
                /// splitter.
                function _processPayment() internal {
                    paymentSplitter.sendValue(msg.value);
                }
                // -------------------------------------------------------------------------
                //
                //  Metadata
                //
                // -------------------------------------------------------------------------
                /// @notice Change tokenURI() base path.
                /// @param uri The new base path (must not contain trailing slash)
                function setBaseTokenURI(string calldata uri) external onlyOwner {
                    _baseTokenURI = uri;
                }
                /// @notice Returns the URI for token metadata.
                function tokenURI(uint256 tokenId)
                    public
                    view
                    override
                    tokenExists(tokenId)
                    returns (string memory)
                {
                    return
                        string(
                            abi.encodePacked(
                                _baseTokenURI,
                                "/",
                                Strings.toString(tokenId),
                                ".json"
                            )
                        );
                }
                /// @notice Returns the seed of a token.
                /// @dev The seed is computed from the seed of the batch in which the given
                /// token was minted.
                function tokenSeed(uint256 tokenId)
                    public
                    view
                    tokenExists(tokenId)
                    returns (bytes32)
                {
                    uint24 batchSeed = _ownershipOf(tokenId).extraData;
                    return keccak256(abi.encodePacked(address(this), batchSeed, tokenId));
                }
                // -------------------------------------------------------------------------
                //
                //  Internals
                //
                // -------------------------------------------------------------------------
                /// @dev See {IERC165-supportsInterface}.
                function supportsInterface(bytes4 interfaceId)
                    public
                    view
                    virtual
                    override(ERC721ACommon, ERC2981)
                    returns (bool)
                {
                    return
                        ERC721ACommon.supportsInterface(interfaceId) ||
                        ERC2981.supportsInterface(interfaceId);
                }
                // -------------------------------------------------------------------------
                //
                //  Errors
                //
                // -------------------------------------------------------------------------
                error MintDisabled();
                error TooManyMintsRequested();
                error InsufficientTokensRemanining();
                error InvalidPayment();
                error OnlyEOA();
                error WrongNumberOfReserveMints();
                error SignatureAlreadyUsed();
                error WrongMintingStage();
            }
            // SPDX-License-Identifier: MIT
            // Copyright 2021 David Huber (@cxkoda)
            pragma solidity >=0.8.0 <0.9.0;
            import "./IERC2981.sol";
            import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
            /**
             * @notice ERC2981 royalty info base contract
             * @dev Implements `supportsInterface`
             */
            abstract contract ERC2981 is IERC2981, ERC165 {
                /**
                 * @dev See {IERC165-supportsInterface}.
                 */
                function supportsInterface(bytes4 interfaceId)
                    public
                    view
                    virtual
                    override(ERC165, IERC165)
                    returns (bool)
                {
                    return
                        interfaceId == type(IERC2981).interfaceId ||
                        super.supportsInterface(interfaceId);
                }
            }
            // SPDX-License-Identifier: MIT
            // Copyright 2021 David Huber (@cxkoda)
            pragma solidity >=0.8.0 <0.9.0;
            import "./ERC2981.sol";
            /**
             * @notice ERC2981 royalty info implementation for a single beneficiary
             * receving a percentage of sales prices.
             * @author David Huber (@cxkoda)
             */
            contract ERC2981SinglePercentual is ERC2981 {
                /**
                 * @dev The royalty percentage (in units of 0.01%)
                 */
                uint96 private _percentage;
                /**
                 * @dev The address to receive the royalties
                 */
                address private _receiver;
                /**
                 * @dev See {IERC2981-royaltyInfo}.
                 */
                function royaltyInfo(uint256, uint256 salePrice)
                    external
                    view
                    override
                    returns (address receiver, uint256 royaltyAmount)
                {
                    royaltyAmount = (salePrice / 10000) * _percentage;
                    receiver = _receiver;
                }
                /**
                 * @dev Sets the royalty percentage (in units of 0.01%)
                 */
                function _setRoyaltyPercentage(uint96 percentage_) internal {
                    _percentage = percentage_;
                }
                /**
                 * @dev Sets the address to receive the royalties
                 */
                function _setRoyaltyReceiver(address receiver_) internal {
                    _receiver = receiver_;
                }
            }
            // SPDX-License-Identifier: None
            pragma solidity >=0.8.0 <0.9.0;
            import "@openzeppelin/contracts/utils/introspection/IERC165.sol";
            /**
             * @dev Interface for the NFT Royalty Standard
             * @author Taken from https://eips.ethereum.org/EIPS/eip-2981
             */
            interface IERC2981 is IERC165 {
                /**
                 * @notice Called with the sale price to determine how much royalty
                 * is owed and to whom.
                 * @param tokenId - the NFT asset queried for royalty information
                 * @param salePrice - the sale price of the NFT asset specified by _tokenId
                 * @return receiver - address of who should be sent the royalty payment
                 * @return royaltyAmount - the royalty payment amount for _salePrice
                 */
                function royaltyInfo(uint256 tokenId, uint256 salePrice)
                    external
                    view
                    returns (address receiver, uint256 royaltyAmount);
            }
            // SPDX-License-Identifier: MIT
            // ERC721A Contracts v4.1.0
            // Creator: Chiru Labs
            pragma solidity ^0.8.4;
            import './IERC721A.sol';
            /**
             * @dev ERC721 token receiver interface.
             */
            interface ERC721A__IERC721Receiver {
                function onERC721Received(
                    address operator,
                    address from,
                    uint256 tokenId,
                    bytes calldata data
                ) external returns (bytes4);
            }
            /**
             * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard,
             * including the Metadata extension. Built to optimize for lower gas during batch mints.
             *
             * Assumes serials are sequentially minted starting at `_startTokenId()`
             * (defaults to 0, e.g. 0, 1, 2, 3..).
             *
             * Assumes that an owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
             *
             * Assumes that the maximum token id cannot exceed 2**256 - 1 (max value of uint256).
             */
            contract ERC721A is IERC721A {
                // Mask of an entry in packed address data.
                uint256 private constant BITMASK_ADDRESS_DATA_ENTRY = (1 << 64) - 1;
                // The bit position of `numberMinted` in packed address data.
                uint256 private constant BITPOS_NUMBER_MINTED = 64;
                // The bit position of `numberBurned` in packed address data.
                uint256 private constant BITPOS_NUMBER_BURNED = 128;
                // The bit position of `aux` in packed address data.
                uint256 private constant BITPOS_AUX = 192;
                // Mask of all 256 bits in packed address data except the 64 bits for `aux`.
                uint256 private constant BITMASK_AUX_COMPLEMENT = (1 << 192) - 1;
                // The bit position of `startTimestamp` in packed ownership.
                uint256 private constant BITPOS_START_TIMESTAMP = 160;
                // The bit mask of the `burned` bit in packed ownership.
                uint256 private constant BITMASK_BURNED = 1 << 224;
                // The bit position of the `nextInitialized` bit in packed ownership.
                uint256 private constant BITPOS_NEXT_INITIALIZED = 225;
                // The bit mask of the `nextInitialized` bit in packed ownership.
                uint256 private constant BITMASK_NEXT_INITIALIZED = 1 << 225;
                // The bit position of `extraData` in packed ownership.
                uint256 private constant BITPOS_EXTRA_DATA = 232;
                // Mask of all 256 bits in a packed ownership except the 24 bits for `extraData`.
                uint256 private constant BITMASK_EXTRA_DATA_COMPLEMENT = (1 << 232) - 1;
                // The mask of the lower 160 bits for addresses.
                uint256 private constant BITMASK_ADDRESS = (1 << 160) - 1;
                // The maximum `quantity` that can be minted with `_mintERC2309`.
                // This limit is to prevent overflows on the address data entries.
                // For a limit of 5000, a total of 3.689e15 calls to `_mintERC2309`
                // is required to cause an overflow, which is unrealistic.
                uint256 private constant MAX_MINT_ERC2309_QUANTITY_LIMIT = 5000;
                // The tokenId of the next token to be minted.
                uint256 private _currentIndex;
                // The number of tokens burned.
                uint256 private _burnCounter;
                // Token name
                string private _name;
                // Token symbol
                string private _symbol;
                // Mapping from token ID to ownership details
                // An empty struct value does not necessarily mean the token is unowned.
                // See `_packedOwnershipOf` implementation for details.
                //
                // Bits Layout:
                // - [0..159]   `addr`
                // - [160..223] `startTimestamp`
                // - [224]      `burned`
                // - [225]      `nextInitialized`
                // - [232..255] `extraData`
                mapping(uint256 => uint256) private _packedOwnerships;
                // Mapping owner address to address data.
                //
                // Bits Layout:
                // - [0..63]    `balance`
                // - [64..127]  `numberMinted`
                // - [128..191] `numberBurned`
                // - [192..255] `aux`
                mapping(address => uint256) private _packedAddressData;
                // Mapping from token ID to approved address.
                mapping(uint256 => address) private _tokenApprovals;
                // Mapping from owner to operator approvals
                mapping(address => mapping(address => bool)) private _operatorApprovals;
                constructor(string memory name_, string memory symbol_) {
                    _name = name_;
                    _symbol = symbol_;
                    _currentIndex = _startTokenId();
                }
                /**
                 * @dev Returns the starting token ID.
                 * To change the starting token ID, please override this function.
                 */
                function _startTokenId() internal view virtual returns (uint256) {
                    return 0;
                }
                /**
                 * @dev Returns the next token ID to be minted.
                 */
                function _nextTokenId() internal view returns (uint256) {
                    return _currentIndex;
                }
                /**
                 * @dev Returns the total number of tokens in existence.
                 * Burned tokens will reduce the count.
                 * To get the total number of tokens minted, please see `_totalMinted`.
                 */
                function totalSupply() public view override returns (uint256) {
                    // Counter underflow is impossible as _burnCounter cannot be incremented
                    // more than `_currentIndex - _startTokenId()` times.
                    unchecked {
                        return _currentIndex - _burnCounter - _startTokenId();
                    }
                }
                /**
                 * @dev Returns the total amount of tokens minted in the contract.
                 */
                function _totalMinted() internal view returns (uint256) {
                    // Counter underflow is impossible as _currentIndex does not decrement,
                    // and it is initialized to `_startTokenId()`
                    unchecked {
                        return _currentIndex - _startTokenId();
                    }
                }
                /**
                 * @dev Returns the total number of tokens burned.
                 */
                function _totalBurned() internal view returns (uint256) {
                    return _burnCounter;
                }
                /**
                 * @dev See {IERC165-supportsInterface}.
                 */
                function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                    // The interface IDs are constants representing the first 4 bytes of the XOR of
                    // all function selectors in the interface. See: https://eips.ethereum.org/EIPS/eip-165
                    // e.g. `bytes4(i.functionA.selector ^ i.functionB.selector ^ ...)`
                    return
                        interfaceId == 0x01ffc9a7 || // ERC165 interface ID for ERC165.
                        interfaceId == 0x80ac58cd || // ERC165 interface ID for ERC721.
                        interfaceId == 0x5b5e139f; // ERC165 interface ID for ERC721Metadata.
                }
                /**
                 * @dev See {IERC721-balanceOf}.
                 */
                function balanceOf(address owner) public view override returns (uint256) {
                    if (owner == address(0)) revert BalanceQueryForZeroAddress();
                    return _packedAddressData[owner] & BITMASK_ADDRESS_DATA_ENTRY;
                }
                /**
                 * Returns the number of tokens minted by `owner`.
                 */
                function _numberMinted(address owner) internal view returns (uint256) {
                    return (_packedAddressData[owner] >> BITPOS_NUMBER_MINTED) & BITMASK_ADDRESS_DATA_ENTRY;
                }
                /**
                 * Returns the number of tokens burned by or on behalf of `owner`.
                 */
                function _numberBurned(address owner) internal view returns (uint256) {
                    return (_packedAddressData[owner] >> BITPOS_NUMBER_BURNED) & BITMASK_ADDRESS_DATA_ENTRY;
                }
                /**
                 * Returns the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
                 */
                function _getAux(address owner) internal view returns (uint64) {
                    return uint64(_packedAddressData[owner] >> BITPOS_AUX);
                }
                /**
                 * Sets the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
                 * If there are multiple variables, please pack them into a uint64.
                 */
                function _setAux(address owner, uint64 aux) internal {
                    uint256 packed = _packedAddressData[owner];
                    uint256 auxCasted;
                    // Cast `aux` with assembly to avoid redundant masking.
                    assembly {
                        auxCasted := aux
                    }
                    packed = (packed & BITMASK_AUX_COMPLEMENT) | (auxCasted << BITPOS_AUX);
                    _packedAddressData[owner] = packed;
                }
                /**
                 * Returns the packed ownership data of `tokenId`.
                 */
                function _packedOwnershipOf(uint256 tokenId) private view returns (uint256) {
                    uint256 curr = tokenId;
                    unchecked {
                        if (_startTokenId() <= curr)
                            if (curr < _currentIndex) {
                                uint256 packed = _packedOwnerships[curr];
                                // If not burned.
                                if (packed & BITMASK_BURNED == 0) {
                                    // Invariant:
                                    // There will always be an ownership that has an address and is not burned
                                    // before an ownership that does not have an address and is not burned.
                                    // Hence, curr will not underflow.
                                    //
                                    // We can directly compare the packed value.
                                    // If the address is zero, packed is zero.
                                    while (packed == 0) {
                                        packed = _packedOwnerships[--curr];
                                    }
                                    return packed;
                                }
                            }
                    }
                    revert OwnerQueryForNonexistentToken();
                }
                /**
                 * Returns the unpacked `TokenOwnership` struct from `packed`.
                 */
                function _unpackedOwnership(uint256 packed) private pure returns (TokenOwnership memory ownership) {
                    ownership.addr = address(uint160(packed));
                    ownership.startTimestamp = uint64(packed >> BITPOS_START_TIMESTAMP);
                    ownership.burned = packed & BITMASK_BURNED != 0;
                    ownership.extraData = uint24(packed >> BITPOS_EXTRA_DATA);
                }
                /**
                 * Returns the unpacked `TokenOwnership` struct at `index`.
                 */
                function _ownershipAt(uint256 index) internal view returns (TokenOwnership memory) {
                    return _unpackedOwnership(_packedOwnerships[index]);
                }
                /**
                 * @dev Initializes the ownership slot minted at `index` for efficiency purposes.
                 */
                function _initializeOwnershipAt(uint256 index) internal {
                    if (_packedOwnerships[index] == 0) {
                        _packedOwnerships[index] = _packedOwnershipOf(index);
                    }
                }
                /**
                 * Gas spent here starts off proportional to the maximum mint batch size.
                 * It gradually moves to O(1) as tokens get transferred around in the collection over time.
                 */
                function _ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory) {
                    return _unpackedOwnership(_packedOwnershipOf(tokenId));
                }
                /**
                 * @dev Packs ownership data into a single uint256.
                 */
                function _packOwnershipData(address owner, uint256 flags) private view returns (uint256 result) {
                    assembly {
                        // Mask `owner` to the lower 160 bits, in case the upper bits somehow aren't clean.
                        owner := and(owner, BITMASK_ADDRESS)
                        // `owner | (block.timestamp << BITPOS_START_TIMESTAMP) | flags`.
                        result := or(owner, or(shl(BITPOS_START_TIMESTAMP, timestamp()), flags))
                    }
                }
                /**
                 * @dev See {IERC721-ownerOf}.
                 */
                function ownerOf(uint256 tokenId) public view override returns (address) {
                    return address(uint160(_packedOwnershipOf(tokenId)));
                }
                /**
                 * @dev See {IERC721Metadata-name}.
                 */
                function name() public view virtual override returns (string memory) {
                    return _name;
                }
                /**
                 * @dev See {IERC721Metadata-symbol}.
                 */
                function symbol() public view virtual override returns (string memory) {
                    return _symbol;
                }
                /**
                 * @dev See {IERC721Metadata-tokenURI}.
                 */
                function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
                    if (!_exists(tokenId)) revert URIQueryForNonexistentToken();
                    string memory baseURI = _baseURI();
                    return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, _toString(tokenId))) : '';
                }
                /**
                 * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
                 * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
                 * by default, it can be overridden in child contracts.
                 */
                function _baseURI() internal view virtual returns (string memory) {
                    return '';
                }
                /**
                 * @dev Returns the `nextInitialized` flag set if `quantity` equals 1.
                 */
                function _nextInitializedFlag(uint256 quantity) private pure returns (uint256 result) {
                    // For branchless setting of the `nextInitialized` flag.
                    assembly {
                        // `(quantity == 1) << BITPOS_NEXT_INITIALIZED`.
                        result := shl(BITPOS_NEXT_INITIALIZED, eq(quantity, 1))
                    }
                }
                /**
                 * @dev See {IERC721-approve}.
                 */
                function approve(address to, uint256 tokenId) public override {
                    address owner = ownerOf(tokenId);
                    if (_msgSenderERC721A() != owner)
                        if (!isApprovedForAll(owner, _msgSenderERC721A())) {
                            revert ApprovalCallerNotOwnerNorApproved();
                        }
                    _tokenApprovals[tokenId] = to;
                    emit Approval(owner, to, tokenId);
                }
                /**
                 * @dev See {IERC721-getApproved}.
                 */
                function getApproved(uint256 tokenId) public view override returns (address) {
                    if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();
                    return _tokenApprovals[tokenId];
                }
                /**
                 * @dev See {IERC721-setApprovalForAll}.
                 */
                function setApprovalForAll(address operator, bool approved) public virtual override {
                    if (operator == _msgSenderERC721A()) revert ApproveToCaller();
                    _operatorApprovals[_msgSenderERC721A()][operator] = approved;
                    emit ApprovalForAll(_msgSenderERC721A(), operator, approved);
                }
                /**
                 * @dev See {IERC721-isApprovedForAll}.
                 */
                function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
                    return _operatorApprovals[owner][operator];
                }
                /**
                 * @dev See {IERC721-safeTransferFrom}.
                 */
                function safeTransferFrom(
                    address from,
                    address to,
                    uint256 tokenId
                ) public virtual override {
                    safeTransferFrom(from, to, tokenId, '');
                }
                /**
                 * @dev See {IERC721-safeTransferFrom}.
                 */
                function safeTransferFrom(
                    address from,
                    address to,
                    uint256 tokenId,
                    bytes memory _data
                ) public virtual override {
                    transferFrom(from, to, tokenId);
                    if (to.code.length != 0)
                        if (!_checkContractOnERC721Received(from, to, tokenId, _data)) {
                            revert TransferToNonERC721ReceiverImplementer();
                        }
                }
                /**
                 * @dev Returns whether `tokenId` exists.
                 *
                 * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
                 *
                 * Tokens start existing when they are minted (`_mint`),
                 */
                function _exists(uint256 tokenId) internal view returns (bool) {
                    return
                        _startTokenId() <= tokenId &&
                        tokenId < _currentIndex && // If within bounds,
                        _packedOwnerships[tokenId] & BITMASK_BURNED == 0; // and not burned.
                }
                /**
                 * @dev Equivalent to `_safeMint(to, quantity, '')`.
                 */
                function _safeMint(address to, uint256 quantity) internal {
                    _safeMint(to, quantity, '');
                }
                /**
                 * @dev Safely mints `quantity` tokens and transfers them to `to`.
                 *
                 * Requirements:
                 *
                 * - If `to` refers to a smart contract, it must implement
                 *   {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
                 * - `quantity` must be greater than 0.
                 *
                 * See {_mint}.
                 *
                 * Emits a {Transfer} event for each mint.
                 */
                function _safeMint(
                    address to,
                    uint256 quantity,
                    bytes memory _data
                ) internal {
                    _mint(to, quantity);
                    unchecked {
                        if (to.code.length != 0) {
                            uint256 end = _currentIndex;
                            uint256 index = end - quantity;
                            do {
                                if (!_checkContractOnERC721Received(address(0), to, index++, _data)) {
                                    revert TransferToNonERC721ReceiverImplementer();
                                }
                            } while (index < end);
                            // Reentrancy protection.
                            if (_currentIndex != end) revert();
                        }
                    }
                }
                /**
                 * @dev Mints `quantity` tokens and transfers them to `to`.
                 *
                 * Requirements:
                 *
                 * - `to` cannot be the zero address.
                 * - `quantity` must be greater than 0.
                 *
                 * Emits a {Transfer} event for each mint.
                 */
                function _mint(address to, uint256 quantity) internal {
                    uint256 startTokenId = _currentIndex;
                    if (to == address(0)) revert MintToZeroAddress();
                    if (quantity == 0) revert MintZeroQuantity();
                    _beforeTokenTransfers(address(0), to, startTokenId, quantity);
                    // Overflows are incredibly unrealistic.
                    // `balance` and `numberMinted` have a maximum limit of 2**64.
                    // `tokenId` has a maximum limit of 2**256.
                    unchecked {
                        // Updates:
                        // - `balance += quantity`.
                        // - `numberMinted += quantity`.
                        //
                        // We can directly add to the `balance` and `numberMinted`.
                        _packedAddressData[to] += quantity * ((1 << BITPOS_NUMBER_MINTED) | 1);
                        // Updates:
                        // - `address` to the owner.
                        // - `startTimestamp` to the timestamp of minting.
                        // - `burned` to `false`.
                        // - `nextInitialized` to `quantity == 1`.
                        _packedOwnerships[startTokenId] = _packOwnershipData(
                            to,
                            _nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
                        );
                        uint256 tokenId = startTokenId;
                        uint256 end = startTokenId + quantity;
                        do {
                            emit Transfer(address(0), to, tokenId++);
                        } while (tokenId < end);
                        _currentIndex = end;
                    }
                    _afterTokenTransfers(address(0), to, startTokenId, quantity);
                }
                /**
                 * @dev Mints `quantity` tokens and transfers them to `to`.
                 *
                 * This function is intended for efficient minting only during contract creation.
                 *
                 * It emits only one {ConsecutiveTransfer} as defined in
                 * [ERC2309](https://eips.ethereum.org/EIPS/eip-2309),
                 * instead of a sequence of {Transfer} event(s).
                 *
                 * Calling this function outside of contract creation WILL make your contract
                 * non-compliant with the ERC721 standard.
                 * For full ERC721 compliance, substituting ERC721 {Transfer} event(s) with the ERC2309
                 * {ConsecutiveTransfer} event is only permissible during contract creation.
                 *
                 * Requirements:
                 *
                 * - `to` cannot be the zero address.
                 * - `quantity` must be greater than 0.
                 *
                 * Emits a {ConsecutiveTransfer} event.
                 */
                function _mintERC2309(address to, uint256 quantity) internal {
                    uint256 startTokenId = _currentIndex;
                    if (to == address(0)) revert MintToZeroAddress();
                    if (quantity == 0) revert MintZeroQuantity();
                    if (quantity > MAX_MINT_ERC2309_QUANTITY_LIMIT) revert MintERC2309QuantityExceedsLimit();
                    _beforeTokenTransfers(address(0), to, startTokenId, quantity);
                    // Overflows are unrealistic due to the above check for `quantity` to be below the limit.
                    unchecked {
                        // Updates:
                        // - `balance += quantity`.
                        // - `numberMinted += quantity`.
                        //
                        // We can directly add to the `balance` and `numberMinted`.
                        _packedAddressData[to] += quantity * ((1 << BITPOS_NUMBER_MINTED) | 1);
                        // Updates:
                        // - `address` to the owner.
                        // - `startTimestamp` to the timestamp of minting.
                        // - `burned` to `false`.
                        // - `nextInitialized` to `quantity == 1`.
                        _packedOwnerships[startTokenId] = _packOwnershipData(
                            to,
                            _nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
                        );
                        emit ConsecutiveTransfer(startTokenId, startTokenId + quantity - 1, address(0), to);
                        _currentIndex = startTokenId + quantity;
                    }
                    _afterTokenTransfers(address(0), to, startTokenId, quantity);
                }
                /**
                 * @dev Returns the storage slot and value for the approved address of `tokenId`.
                 */
                function _getApprovedAddress(uint256 tokenId)
                    private
                    view
                    returns (uint256 approvedAddressSlot, address approvedAddress)
                {
                    mapping(uint256 => address) storage tokenApprovalsPtr = _tokenApprovals;
                    // The following is equivalent to `approvedAddress = _tokenApprovals[tokenId]`.
                    assembly {
                        // Compute the slot.
                        mstore(0x00, tokenId)
                        mstore(0x20, tokenApprovalsPtr.slot)
                        approvedAddressSlot := keccak256(0x00, 0x40)
                        // Load the slot's value from storage.
                        approvedAddress := sload(approvedAddressSlot)
                    }
                }
                /**
                 * @dev Returns whether the `approvedAddress` is equals to `from` or `msgSender`.
                 */
                function _isOwnerOrApproved(
                    address approvedAddress,
                    address from,
                    address msgSender
                ) private pure returns (bool result) {
                    assembly {
                        // Mask `from` to the lower 160 bits, in case the upper bits somehow aren't clean.
                        from := and(from, BITMASK_ADDRESS)
                        // Mask `msgSender` to the lower 160 bits, in case the upper bits somehow aren't clean.
                        msgSender := and(msgSender, BITMASK_ADDRESS)
                        // `msgSender == from || msgSender == approvedAddress`.
                        result := or(eq(msgSender, from), eq(msgSender, approvedAddress))
                    }
                }
                /**
                 * @dev Transfers `tokenId` from `from` to `to`.
                 *
                 * Requirements:
                 *
                 * - `to` cannot be the zero address.
                 * - `tokenId` token must be owned by `from`.
                 *
                 * Emits a {Transfer} event.
                 */
                function transferFrom(
                    address from,
                    address to,
                    uint256 tokenId
                ) public virtual override {
                    uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);
                    if (address(uint160(prevOwnershipPacked)) != from) revert TransferFromIncorrectOwner();
                    (uint256 approvedAddressSlot, address approvedAddress) = _getApprovedAddress(tokenId);
                    // The nested ifs save around 20+ gas over a compound boolean condition.
                    if (!_isOwnerOrApproved(approvedAddress, from, _msgSenderERC721A()))
                        if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();
                    if (to == address(0)) revert TransferToZeroAddress();
                    _beforeTokenTransfers(from, to, tokenId, 1);
                    // Clear approvals from the previous owner.
                    assembly {
                        if approvedAddress {
                            // This is equivalent to `delete _tokenApprovals[tokenId]`.
                            sstore(approvedAddressSlot, 0)
                        }
                    }
                    // Underflow of the sender's balance is impossible because we check for
                    // ownership above and the recipient's balance can't realistically overflow.
                    // Counter overflow is incredibly unrealistic as tokenId would have to be 2**256.
                    unchecked {
                        // We can directly increment and decrement the balances.
                        --_packedAddressData[from]; // Updates: `balance -= 1`.
                        ++_packedAddressData[to]; // Updates: `balance += 1`.
                        // Updates:
                        // - `address` to the next owner.
                        // - `startTimestamp` to the timestamp of transfering.
                        // - `burned` to `false`.
                        // - `nextInitialized` to `true`.
                        _packedOwnerships[tokenId] = _packOwnershipData(
                            to,
                            BITMASK_NEXT_INITIALIZED | _nextExtraData(from, to, prevOwnershipPacked)
                        );
                        // If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
                        if (prevOwnershipPacked & BITMASK_NEXT_INITIALIZED == 0) {
                            uint256 nextTokenId = tokenId + 1;
                            // If the next slot's address is zero and not burned (i.e. packed value is zero).
                            if (_packedOwnerships[nextTokenId] == 0) {
                                // If the next slot is within bounds.
                                if (nextTokenId != _currentIndex) {
                                    // Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
                                    _packedOwnerships[nextTokenId] = prevOwnershipPacked;
                                }
                            }
                        }
                    }
                    emit Transfer(from, to, tokenId);
                    _afterTokenTransfers(from, to, tokenId, 1);
                }
                /**
                 * @dev Equivalent to `_burn(tokenId, false)`.
                 */
                function _burn(uint256 tokenId) internal virtual {
                    _burn(tokenId, false);
                }
                /**
                 * @dev Destroys `tokenId`.
                 * The approval is cleared when the token is burned.
                 *
                 * Requirements:
                 *
                 * - `tokenId` must exist.
                 *
                 * Emits a {Transfer} event.
                 */
                function _burn(uint256 tokenId, bool approvalCheck) internal virtual {
                    uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);
                    address from = address(uint160(prevOwnershipPacked));
                    (uint256 approvedAddressSlot, address approvedAddress) = _getApprovedAddress(tokenId);
                    if (approvalCheck) {
                        // The nested ifs save around 20+ gas over a compound boolean condition.
                        if (!_isOwnerOrApproved(approvedAddress, from, _msgSenderERC721A()))
                            if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();
                    }
                    _beforeTokenTransfers(from, address(0), tokenId, 1);
                    // Clear approvals from the previous owner.
                    assembly {
                        if approvedAddress {
                            // This is equivalent to `delete _tokenApprovals[tokenId]`.
                            sstore(approvedAddressSlot, 0)
                        }
                    }
                    // Underflow of the sender's balance is impossible because we check for
                    // ownership above and the recipient's balance can't realistically overflow.
                    // Counter overflow is incredibly unrealistic as `tokenId` would have to be 2**256.
                    unchecked {
                        // Updates:
                        // - `balance -= 1`.
                        // - `numberBurned += 1`.
                        //
                        // We can directly decrement the balance, and increment the number burned.
                        // This is equivalent to `packed -= 1; packed += 1 << BITPOS_NUMBER_BURNED;`.
                        _packedAddressData[from] += (1 << BITPOS_NUMBER_BURNED) - 1;
                        // Updates:
                        // - `address` to the last owner.
                        // - `startTimestamp` to the timestamp of burning.
                        // - `burned` to `true`.
                        // - `nextInitialized` to `true`.
                        _packedOwnerships[tokenId] = _packOwnershipData(
                            from,
                            (BITMASK_BURNED | BITMASK_NEXT_INITIALIZED) | _nextExtraData(from, address(0), prevOwnershipPacked)
                        );
                        // If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
                        if (prevOwnershipPacked & BITMASK_NEXT_INITIALIZED == 0) {
                            uint256 nextTokenId = tokenId + 1;
                            // If the next slot's address is zero and not burned (i.e. packed value is zero).
                            if (_packedOwnerships[nextTokenId] == 0) {
                                // If the next slot is within bounds.
                                if (nextTokenId != _currentIndex) {
                                    // Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
                                    _packedOwnerships[nextTokenId] = prevOwnershipPacked;
                                }
                            }
                        }
                    }
                    emit Transfer(from, address(0), tokenId);
                    _afterTokenTransfers(from, address(0), tokenId, 1);
                    // Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.
                    unchecked {
                        _burnCounter++;
                    }
                }
                /**
                 * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target contract.
                 *
                 * @param from address representing the previous owner of the given token ID
                 * @param to target address that will receive the tokens
                 * @param tokenId uint256 ID of the token to be transferred
                 * @param _data bytes optional data to send along with the call
                 * @return bool whether the call correctly returned the expected magic value
                 */
                function _checkContractOnERC721Received(
                    address from,
                    address to,
                    uint256 tokenId,
                    bytes memory _data
                ) private returns (bool) {
                    try ERC721A__IERC721Receiver(to).onERC721Received(_msgSenderERC721A(), from, tokenId, _data) returns (
                        bytes4 retval
                    ) {
                        return retval == ERC721A__IERC721Receiver(to).onERC721Received.selector;
                    } catch (bytes memory reason) {
                        if (reason.length == 0) {
                            revert TransferToNonERC721ReceiverImplementer();
                        } else {
                            assembly {
                                revert(add(32, reason), mload(reason))
                            }
                        }
                    }
                }
                /**
                 * @dev Directly sets the extra data for the ownership data `index`.
                 */
                function _setExtraDataAt(uint256 index, uint24 extraData) internal {
                    uint256 packed = _packedOwnerships[index];
                    if (packed == 0) revert OwnershipNotInitializedForExtraData();
                    uint256 extraDataCasted;
                    // Cast `extraData` with assembly to avoid redundant masking.
                    assembly {
                        extraDataCasted := extraData
                    }
                    packed = (packed & BITMASK_EXTRA_DATA_COMPLEMENT) | (extraDataCasted << BITPOS_EXTRA_DATA);
                    _packedOwnerships[index] = packed;
                }
                /**
                 * @dev Returns the next extra data for the packed ownership data.
                 * The returned result is shifted into position.
                 */
                function _nextExtraData(
                    address from,
                    address to,
                    uint256 prevOwnershipPacked
                ) private view returns (uint256) {
                    uint24 extraData = uint24(prevOwnershipPacked >> BITPOS_EXTRA_DATA);
                    return uint256(_extraData(from, to, extraData)) << BITPOS_EXTRA_DATA;
                }
                /**
                 * @dev Called during each token transfer to set the 24bit `extraData` field.
                 * Intended to be overridden by the cosumer contract.
                 *
                 * `previousExtraData` - the value of `extraData` before transfer.
                 *
                 * Calling conditions:
                 *
                 * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
                 * transferred to `to`.
                 * - When `from` is zero, `tokenId` will be minted for `to`.
                 * - When `to` is zero, `tokenId` will be burned by `from`.
                 * - `from` and `to` are never both zero.
                 */
                function _extraData(
                    address from,
                    address to,
                    uint24 previousExtraData
                ) internal view virtual returns (uint24) {}
                /**
                 * @dev Hook that is called before a set of serially-ordered token ids are about to be transferred.
                 * This includes minting.
                 * And also called before burning one token.
                 *
                 * startTokenId - the first token id to be transferred
                 * quantity - the amount to be transferred
                 *
                 * Calling conditions:
                 *
                 * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
                 * transferred to `to`.
                 * - When `from` is zero, `tokenId` will be minted for `to`.
                 * - When `to` is zero, `tokenId` will be burned by `from`.
                 * - `from` and `to` are never both zero.
                 */
                function _beforeTokenTransfers(
                    address from,
                    address to,
                    uint256 startTokenId,
                    uint256 quantity
                ) internal virtual {}
                /**
                 * @dev Hook that is called after a set of serially-ordered token ids have been transferred.
                 * This includes minting.
                 * And also called after one token has been burned.
                 *
                 * startTokenId - the first token id to be transferred
                 * quantity - the amount to be transferred
                 *
                 * Calling conditions:
                 *
                 * - When `from` and `to` are both non-zero, `from`'s `tokenId` has been
                 * transferred to `to`.
                 * - When `from` is zero, `tokenId` has been minted for `to`.
                 * - When `to` is zero, `tokenId` has been burned by `from`.
                 * - `from` and `to` are never both zero.
                 */
                function _afterTokenTransfers(
                    address from,
                    address to,
                    uint256 startTokenId,
                    uint256 quantity
                ) internal virtual {}
                /**
                 * @dev Returns the message sender (defaults to `msg.sender`).
                 *
                 * If you are writing GSN compatible contracts, you need to override this function.
                 */
                function _msgSenderERC721A() internal view virtual returns (address) {
                    return msg.sender;
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                 */
                function _toString(uint256 value) internal pure returns (string memory ptr) {
                    assembly {
                        // The maximum value of a uint256 contains 78 digits (1 byte per digit),
                        // but we allocate 128 bytes to keep the free memory pointer 32-byte word aliged.
                        // We will need 1 32-byte word to store the length,
                        // and 3 32-byte words to store a maximum of 78 digits. Total: 32 + 3 * 32 = 128.
                        ptr := add(mload(0x40), 128)
                        // Update the free memory pointer to allocate.
                        mstore(0x40, ptr)
                        // Cache the end of the memory to calculate the length later.
                        let end := ptr
                        // We write the string from the rightmost digit to the leftmost digit.
                        // The following is essentially a do-while loop that also handles the zero case.
                        // Costs a bit more than early returning for the zero case,
                        // but cheaper in terms of deployment and overall runtime costs.
                        for {
                            // Initialize and perform the first pass without check.
                            let temp := value
                            // Move the pointer 1 byte leftwards to point to an empty character slot.
                            ptr := sub(ptr, 1)
                            // Write the character to the pointer. 48 is the ASCII index of '0'.
                            mstore8(ptr, add(48, mod(temp, 10)))
                            temp := div(temp, 10)
                        } temp {
                            // Keep dividing `temp` until zero.
                            temp := div(temp, 10)
                        } {
                            // Body of the for loop.
                            ptr := sub(ptr, 1)
                            mstore8(ptr, add(48, mod(temp, 10)))
                        }
                        let length := sub(end, ptr)
                        // Move the pointer 32 bytes leftwards to make room for the length.
                        ptr := sub(ptr, 32)
                        // Store the length.
                        mstore(ptr, length)
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            // ERC721A Contracts v4.1.0
            // Creator: Chiru Labs
            pragma solidity ^0.8.4;
            /**
             * @dev Interface of an ERC721A compliant contract.
             */
            interface IERC721A {
                /**
                 * The caller must own the token or be an approved operator.
                 */
                error ApprovalCallerNotOwnerNorApproved();
                /**
                 * The token does not exist.
                 */
                error ApprovalQueryForNonexistentToken();
                /**
                 * The caller cannot approve to their own address.
                 */
                error ApproveToCaller();
                /**
                 * Cannot query the balance for the zero address.
                 */
                error BalanceQueryForZeroAddress();
                /**
                 * Cannot mint to the zero address.
                 */
                error MintToZeroAddress();
                /**
                 * The quantity of tokens minted must be more than zero.
                 */
                error MintZeroQuantity();
                /**
                 * The token does not exist.
                 */
                error OwnerQueryForNonexistentToken();
                /**
                 * The caller must own the token or be an approved operator.
                 */
                error TransferCallerNotOwnerNorApproved();
                /**
                 * The token must be owned by `from`.
                 */
                error TransferFromIncorrectOwner();
                /**
                 * Cannot safely transfer to a contract that does not implement the ERC721Receiver interface.
                 */
                error TransferToNonERC721ReceiverImplementer();
                /**
                 * Cannot transfer to the zero address.
                 */
                error TransferToZeroAddress();
                /**
                 * The token does not exist.
                 */
                error URIQueryForNonexistentToken();
                /**
                 * The `quantity` minted with ERC2309 exceeds the safety limit.
                 */
                error MintERC2309QuantityExceedsLimit();
                /**
                 * The `extraData` cannot be set on an unintialized ownership slot.
                 */
                error OwnershipNotInitializedForExtraData();
                struct TokenOwnership {
                    // The address of the owner.
                    address addr;
                    // Keeps track of the start time of ownership with minimal overhead for tokenomics.
                    uint64 startTimestamp;
                    // Whether the token has been burned.
                    bool burned;
                    // Arbitrary data similar to `startTimestamp` that can be set through `_extraData`.
                    uint24 extraData;
                }
                /**
                 * @dev Returns the total amount of tokens stored by the contract.
                 *
                 * Burned tokens are calculated here, use `_totalMinted()` if you want to count just minted tokens.
                 */
                function totalSupply() external view returns (uint256);
                // ==============================
                //            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);
                // ==============================
                //            IERC721
                // ==============================
                /**
                 * @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 be have been allowed to move this token by either {approve} or {setApprovalForAll}.
                 * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                 *
                 * Emits a {Transfer} event.
                 */
                function safeTransferFrom(
                    address from,
                    address to,
                    uint256 tokenId
                ) external;
                /**
                 * @dev Transfers `tokenId` token from `from` to `to`.
                 *
                 * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
                 *
                 * Requirements:
                 *
                 * - `from` cannot be the zero address.
                 * - `to` cannot be the zero address.
                 * - `tokenId` token must be owned by `from`.
                 * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
                 *
                 * Emits a {Transfer} event.
                 */
                function transferFrom(
                    address from,
                    address to,
                    uint256 tokenId
                ) external;
                /**
                 * @dev Gives permission to `to` to transfer `tokenId` token to another account.
                 * The approval is cleared when the token is transferred.
                 *
                 * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
                 *
                 * Requirements:
                 *
                 * - The caller must own the token or be an approved operator.
                 * - `tokenId` must exist.
                 *
                 * Emits an {Approval} event.
                 */
                function approve(address to, uint256 tokenId) external;
                /**
                 * @dev 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);
                // ==============================
                //        IERC721Metadata
                // ==============================
                /**
                 * @dev Returns the token collection name.
                 */
                function name() external view returns (string memory);
                /**
                 * @dev Returns the token collection symbol.
                 */
                function symbol() external view returns (string memory);
                /**
                 * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
                 */
                function tokenURI(uint256 tokenId) external view returns (string memory);
                // ==============================
                //            IERC2309
                // ==============================
                /**
                 * @dev Emitted when tokens in `fromTokenId` to `toTokenId` (inclusive) is transferred from `from` to `to`,
                 * as defined in the ERC2309 standard. See `_mintERC2309` for more details.
                 */
                event ConsecutiveTransfer(uint256 indexed fromTokenId, uint256 toTokenId, address indexed from, address indexed to);
            }
            

            File 3 of 8: DelegatedPaymentSplitter
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2022 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            import "@openzeppelin/contracts-upgradeable/finance/PaymentSplitterUpgradeable.sol";
            /**
            @notice This contract functions identically to a standard OpenZeppelin
            PaymentSplitter except that it can be cheaply cloned and deployed via the
            PaymentSplitterFactory. The upgradeable functionality is not used, but is
            required for cloning with an EIP-1677 minimal contract proxy.
            @dev Cloning only replicates the implementation logic, but not the data
            associated with each clone. See EIP-1677 for details.
            NOTE: there is likely no need to import this contract directly; instead see the
            ethier documentation for the deployed factory addresses.
             */
            contract DelegatedPaymentSplitter is PaymentSplitterUpgradeable {
                /**
                @dev Initializes the PaymentSplitter, akin to a constructor. MUST be called
                by the Factory, in the same transaction as deployment, as there are no
                protections in place.
                 */
                function initialize(address[] memory payees, uint256[] memory shares)
                    external
                    payable
                    initializer
                {
                    __PaymentSplitter_init(payees, shares);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (finance/PaymentSplitter.sol)
            pragma solidity ^0.8.0;
            import "../token/ERC20/utils/SafeERC20Upgradeable.sol";
            import "../utils/AddressUpgradeable.sol";
            import "../utils/ContextUpgradeable.sol";
            import "../proxy/utils/Initializable.sol";
            /**
             * @title PaymentSplitter
             * @dev This contract allows to split Ether payments among a group of accounts. The sender does not need to be aware
             * that the Ether will be split in this way, since it is handled transparently by the contract.
             *
             * The split can be in equal parts or in any other arbitrary proportion. The way this is specified is by assigning each
             * account to a number of shares. Of all the Ether that this contract receives, each account will then be able to claim
             * an amount proportional to the percentage of total shares they were assigned.
             *
             * `PaymentSplitter` follows a _pull payment_ model. This means that payments are not automatically forwarded to the
             * accounts but kept in this contract, and the actual transfer is triggered as a separate step by calling the {release}
             * function.
             *
             * NOTE: This contract assumes that ERC20 tokens will behave similarly to native tokens (Ether). Rebasing tokens, and
             * tokens that apply fees during transfers, are likely to not be supported as expected. If in doubt, we encourage you
             * to run tests before sending real value to this contract.
             */
            contract PaymentSplitterUpgradeable is Initializable, ContextUpgradeable {
                event PayeeAdded(address account, uint256 shares);
                event PaymentReleased(address to, uint256 amount);
                event ERC20PaymentReleased(IERC20Upgradeable indexed token, address to, uint256 amount);
                event PaymentReceived(address from, uint256 amount);
                uint256 private _totalShares;
                uint256 private _totalReleased;
                mapping(address => uint256) private _shares;
                mapping(address => uint256) private _released;
                address[] private _payees;
                mapping(IERC20Upgradeable => uint256) private _erc20TotalReleased;
                mapping(IERC20Upgradeable => mapping(address => uint256)) private _erc20Released;
                /**
                 * @dev Creates an instance of `PaymentSplitter` where each account in `payees` is assigned the number of shares at
                 * the matching position in the `shares` array.
                 *
                 * All addresses in `payees` must be non-zero. Both arrays must have the same non-zero length, and there must be no
                 * duplicates in `payees`.
                 */
                function __PaymentSplitter_init(address[] memory payees, uint256[] memory shares_) internal onlyInitializing {
                    __Context_init_unchained();
                    __PaymentSplitter_init_unchained(payees, shares_);
                }
                function __PaymentSplitter_init_unchained(address[] memory payees, uint256[] memory shares_) internal onlyInitializing {
                    require(payees.length == shares_.length, "PaymentSplitter: payees and shares length mismatch");
                    require(payees.length > 0, "PaymentSplitter: no payees");
                    for (uint256 i = 0; i < payees.length; i++) {
                        _addPayee(payees[i], shares_[i]);
                    }
                }
                /**
                 * @dev The Ether received will be logged with {PaymentReceived} events. Note that these events are not fully
                 * reliable: it's possible for a contract to receive Ether without triggering this function. This only affects the
                 * reliability of the events, and not the actual splitting of Ether.
                 *
                 * To learn more about this see the Solidity documentation for
                 * https://solidity.readthedocs.io/en/latest/contracts.html#fallback-function[fallback
                 * functions].
                 */
                receive() external payable virtual {
                    emit PaymentReceived(_msgSender(), msg.value);
                }
                /**
                 * @dev Getter for the total shares held by payees.
                 */
                function totalShares() public view returns (uint256) {
                    return _totalShares;
                }
                /**
                 * @dev Getter for the total amount of Ether already released.
                 */
                function totalReleased() public view returns (uint256) {
                    return _totalReleased;
                }
                /**
                 * @dev Getter for the total amount of `token` already released. `token` should be the address of an IERC20
                 * contract.
                 */
                function totalReleased(IERC20Upgradeable token) public view returns (uint256) {
                    return _erc20TotalReleased[token];
                }
                /**
                 * @dev Getter for the amount of shares held by an account.
                 */
                function shares(address account) public view returns (uint256) {
                    return _shares[account];
                }
                /**
                 * @dev Getter for the amount of Ether already released to a payee.
                 */
                function released(address account) public view returns (uint256) {
                    return _released[account];
                }
                /**
                 * @dev Getter for the amount of `token` tokens already released to a payee. `token` should be the address of an
                 * IERC20 contract.
                 */
                function released(IERC20Upgradeable token, address account) public view returns (uint256) {
                    return _erc20Released[token][account];
                }
                /**
                 * @dev Getter for the address of the payee number `index`.
                 */
                function payee(uint256 index) public view returns (address) {
                    return _payees[index];
                }
                /**
                 * @dev Triggers a transfer to `account` of the amount of Ether they are owed, according to their percentage of the
                 * total shares and their previous withdrawals.
                 */
                function release(address payable account) public virtual {
                    require(_shares[account] > 0, "PaymentSplitter: account has no shares");
                    uint256 totalReceived = address(this).balance + totalReleased();
                    uint256 payment = _pendingPayment(account, totalReceived, released(account));
                    require(payment != 0, "PaymentSplitter: account is not due payment");
                    _released[account] += payment;
                    _totalReleased += payment;
                    AddressUpgradeable.sendValue(account, payment);
                    emit PaymentReleased(account, payment);
                }
                /**
                 * @dev Triggers a transfer to `account` of the amount of `token` tokens they are owed, according to their
                 * percentage of the total shares and their previous withdrawals. `token` must be the address of an IERC20
                 * contract.
                 */
                function release(IERC20Upgradeable token, address account) public virtual {
                    require(_shares[account] > 0, "PaymentSplitter: account has no shares");
                    uint256 totalReceived = token.balanceOf(address(this)) + totalReleased(token);
                    uint256 payment = _pendingPayment(account, totalReceived, released(token, account));
                    require(payment != 0, "PaymentSplitter: account is not due payment");
                    _erc20Released[token][account] += payment;
                    _erc20TotalReleased[token] += payment;
                    SafeERC20Upgradeable.safeTransfer(token, account, payment);
                    emit ERC20PaymentReleased(token, account, payment);
                }
                /**
                 * @dev internal logic for computing the pending payment of an `account` given the token historical balances and
                 * already released amounts.
                 */
                function _pendingPayment(
                    address account,
                    uint256 totalReceived,
                    uint256 alreadyReleased
                ) private view returns (uint256) {
                    return (totalReceived * _shares[account]) / _totalShares - alreadyReleased;
                }
                /**
                 * @dev Add a new payee to the contract.
                 * @param account The address of the payee to add.
                 * @param shares_ The number of shares owned by the payee.
                 */
                function _addPayee(address account, uint256 shares_) private {
                    require(account != address(0), "PaymentSplitter: account is the zero address");
                    require(shares_ > 0, "PaymentSplitter: shares are 0");
                    require(_shares[account] == 0, "PaymentSplitter: account already has shares");
                    _payees.push(account);
                    _shares[account] = shares_;
                    _totalShares = _totalShares + shares_;
                    emit PayeeAdded(account, shares_);
                }
                uint256[43] private __gap;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (proxy/utils/Initializable.sol)
            pragma solidity ^0.8.0;
            import "../../utils/AddressUpgradeable.sol";
            /**
             * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
             * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
             * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
             * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
             *
             * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
             * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
             *
             * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
             * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
             *
             * [CAUTION]
             * ====
             * Avoid leaving a contract uninitialized.
             *
             * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
             * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
             * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
             *
             * [.hljs-theme-light.nopadding]
             * ```
             * /// @custom:oz-upgrades-unsafe-allow constructor
             * constructor() initializer {}
             * ```
             * ====
             */
            abstract contract Initializable {
                /**
                 * @dev Indicates that the contract has been initialized.
                 */
                bool private _initialized;
                /**
                 * @dev Indicates that the contract is in the process of being initialized.
                 */
                bool private _initializing;
                /**
                 * @dev Modifier to protect an initializer function from being invoked twice.
                 */
                modifier initializer() {
                    // If the contract is initializing we ignore whether _initialized is set in order to support multiple
                    // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
                    // contract may have been reentered.
                    require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");
                    bool isTopLevelCall = !_initializing;
                    if (isTopLevelCall) {
                        _initializing = true;
                        _initialized = true;
                    }
                    _;
                    if (isTopLevelCall) {
                        _initializing = false;
                    }
                }
                /**
                 * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                 * {initializer} modifier, directly or indirectly.
                 */
                modifier onlyInitializing() {
                    require(_initializing, "Initializable: contract is not initializing");
                    _;
                }
                function _isConstructor() private view returns (bool) {
                    return !AddressUpgradeable.isContract(address(this));
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
            pragma solidity ^0.8.0;
            import "../proxy/utils/Initializable.sol";
            /**
             * @dev Provides information about the current execution context, including the
             * sender of the transaction and its data. While these are generally available
             * via msg.sender and msg.data, they should not be accessed in such a direct
             * manner, since when dealing with meta-transactions the account sending and
             * paying for execution may not be the actual sender (as far as an application
             * is concerned).
             *
             * This contract is only required for intermediate, library-like contracts.
             */
            abstract contract ContextUpgradeable is Initializable {
                function __Context_init() internal onlyInitializing {
                    __Context_init_unchained();
                }
                function __Context_init_unchained() internal onlyInitializing {
                }
                function _msgSender() internal view virtual returns (address) {
                    return msg.sender;
                }
                function _msgData() internal view virtual returns (bytes calldata) {
                    return msg.data;
                }
                uint256[50] private __gap;
            }
            // 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 AddressUpgradeable {
                /**
                 * @dev Returns true if `account` is a contract.
                 *
                 * [IMPORTANT]
                 * ====
                 * It is unsafe to assume that an address for which this function returns
                 * false is an externally-owned account (EOA) and not a contract.
                 *
                 * Among others, `isContract` will return false for the following
                 * types of addresses:
                 *
                 *  - an externally-owned account
                 *  - a contract in construction
                 *  - an address where a contract will be created
                 *  - an address where a contract lived, but was destroyed
                 * ====
                 */
                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 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 (token/ERC20/utils/SafeERC20.sol)
            pragma solidity ^0.8.0;
            import "../IERC20Upgradeable.sol";
            import "../../../utils/AddressUpgradeable.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 SafeERC20Upgradeable {
                using AddressUpgradeable for address;
                function safeTransfer(
                    IERC20Upgradeable token,
                    address to,
                    uint256 value
                ) internal {
                    _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                }
                function safeTransferFrom(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(IERC20Upgradeable 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 v4.4.1 (token/ERC20/IERC20.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev Interface of the ERC20 standard as defined in the EIP.
             */
            interface IERC20Upgradeable {
                /**
                 * @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);
            }
            

            File 4 of 8: X2Y2_r1
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            import './IDelegate.sol';
            import './IWETHUpgradable.sol';
            import './MarketConsts.sol';
            import '@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol';
            import '@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol';
            import '@openzeppelin/contracts-upgradeable/security/PausableUpgradeable.sol';
            import '@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol';
            import '@openzeppelin/contracts-upgradeable/token/ERC20/utils/SafeERC20Upgradeable.sol';
            import '@openzeppelin/contracts/utils/cryptography/ECDSA.sol';
            interface IX2Y2Run {
                function run1(
                    Market.Order memory order,
                    Market.SettleShared memory shared,
                    Market.SettleDetail memory detail
                ) external returns (uint256);
            }
            contract X2Y2_r1 is
                Initializable,
                ReentrancyGuardUpgradeable,
                OwnableUpgradeable,
                PausableUpgradeable,
                IX2Y2Run
            {
                using SafeERC20Upgradeable for IERC20Upgradeable;
                event EvProfit(bytes32 itemHash, address currency, address to, uint256 amount);
                event EvAuctionRefund(
                    bytes32 indexed itemHash,
                    address currency,
                    address to,
                    uint256 amount,
                    uint256 incentive
                );
                event EvInventory(
                    bytes32 indexed itemHash,
                    address maker,
                    address taker,
                    uint256 orderSalt,
                    uint256 settleSalt,
                    uint256 intent,
                    uint256 delegateType,
                    uint256 deadline,
                    IERC20Upgradeable currency,
                    bytes dataMask,
                    Market.OrderItem item,
                    Market.SettleDetail detail
                );
                event EvSigner(address signer, bool isRemoval);
                event EvDelegate(address delegate, bool isRemoval);
                event EvFeeCapUpdate(uint256 newValue);
                event EvCancel(bytes32 indexed itemHash);
                event EvFailure(uint256 index, bytes error);
                mapping(address => bool) public delegates;
                mapping(address => bool) public signers;
                mapping(bytes32 => Market.InvStatus) public inventoryStatus;
                mapping(bytes32 => Market.OngoingAuction) public ongoingAuctions;
                uint256 public constant RATE_BASE = 1e6;
                uint256 public feeCapPct;
                IWETHUpgradable public weth;
                receive() external payable {}
                function pause() public onlyOwner {
                    _pause();
                }
                function unpause() public onlyOwner {
                    _unpause();
                }
                function initialize(uint256 feeCapPct_, address weth_) public initializer {
                    feeCapPct = feeCapPct_;
                    weth = IWETHUpgradable(weth_);
                    __ReentrancyGuard_init_unchained();
                    __Pausable_init_unchained();
                    __Ownable_init_unchained();
                }
                function updateFeeCap(uint256 val) public virtual onlyOwner {
                    feeCapPct = val;
                    emit EvFeeCapUpdate(val);
                }
                function updateSigners(address[] memory toAdd, address[] memory toRemove)
                    public
                    virtual
                    onlyOwner
                {
                    for (uint256 i = 0; i < toAdd.length; i++) {
                        signers[toAdd[i]] = true;
                        emit EvSigner(toAdd[i], false);
                    }
                    for (uint256 i = 0; i < toRemove.length; i++) {
                        delete signers[toRemove[i]];
                        emit EvSigner(toRemove[i], true);
                    }
                }
                function updateDelegates(address[] memory toAdd, address[] memory toRemove)
                    public
                    virtual
                    onlyOwner
                {
                    for (uint256 i = 0; i < toAdd.length; i++) {
                        delegates[toAdd[i]] = true;
                        emit EvDelegate(toAdd[i], false);
                    }
                    for (uint256 i = 0; i < toRemove.length; i++) {
                        delete delegates[toRemove[i]];
                        emit EvDelegate(toRemove[i], true);
                    }
                }
                function cancel(
                    bytes32[] memory itemHashes,
                    uint256 deadline,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) public virtual nonReentrant whenNotPaused {
                    require(deadline > block.timestamp, 'deadline reached');
                    bytes32 hash = keccak256(abi.encode(itemHashes.length, itemHashes, deadline));
                    address signer = ECDSA.recover(hash, v, r, s);
                    require(signers[signer], 'Input signature error');
                    for (uint256 i = 0; i < itemHashes.length; i++) {
                        bytes32 h = itemHashes[i];
                        if (inventoryStatus[h] == Market.InvStatus.NEW) {
                            inventoryStatus[h] = Market.InvStatus.CANCELLED;
                            emit EvCancel(h);
                        }
                    }
                }
                function run(Market.RunInput memory input) public payable virtual nonReentrant whenNotPaused {
                    require(input.shared.deadline > block.timestamp, 'input deadline reached');
                    require(msg.sender == input.shared.user, 'sender does not match');
                    _verifyInputSignature(input);
                    uint256 amountEth = msg.value;
                    if (input.shared.amountToWeth > 0) {
                        uint256 amt = input.shared.amountToWeth;
                        weth.deposit{value: amt}();
                        SafeERC20Upgradeable.safeTransfer(weth, msg.sender, amt);
                        amountEth -= amt;
                    }
                    if (input.shared.amountToEth > 0) {
                        uint256 amt = input.shared.amountToEth;
                        SafeERC20Upgradeable.safeTransferFrom(weth, msg.sender, address(this), amt);
                        weth.withdraw(amt);
                        amountEth += amt;
                    }
                    for (uint256 i = 0; i < input.orders.length; i++) {
                        _verifyOrderSignature(input.orders[i]);
                    }
                    for (uint256 i = 0; i < input.details.length; i++) {
                        Market.SettleDetail memory detail = input.details[i];
                        Market.Order memory order = input.orders[detail.orderIdx];
                        if (input.shared.canFail) {
                            try IX2Y2Run(address(this)).run1(order, input.shared, detail) returns (
                                uint256 ethPayment
                            ) {
                                amountEth -= ethPayment;
                            } catch Error(string memory _err) {
                                emit EvFailure(i, bytes(_err));
                            } catch (bytes memory _err) {
                                emit EvFailure(i, _err);
                            }
                        } else {
                            amountEth -= _run(order, input.shared, detail);
                        }
                    }
                    if (amountEth > 0) {
                        payable(msg.sender).transfer(amountEth);
                    }
                }
                function run1(
                    Market.Order memory order,
                    Market.SettleShared memory shared,
                    Market.SettleDetail memory detail
                ) external virtual returns (uint256) {
                    require(msg.sender == address(this), 'unsafe call');
                    return _run(order, shared, detail);
                }
                function _hashItem(Market.Order memory order, Market.OrderItem memory item)
                    internal
                    view
                    virtual
                    returns (bytes32)
                {
                    return
                        keccak256(
                            abi.encode(
                                order.salt,
                                order.user,
                                order.network,
                                order.intent,
                                order.delegateType,
                                order.deadline,
                                order.currency,
                                order.dataMask,
                                item
                            )
                        );
                }
                function _emitInventory(
                    bytes32 itemHash,
                    Market.Order memory order,
                    Market.OrderItem memory item,
                    Market.SettleShared memory shared,
                    Market.SettleDetail memory detail
                ) internal virtual {
                    emit EvInventory(
                        itemHash,
                        order.user,
                        shared.user,
                        order.salt,
                        shared.salt,
                        order.intent,
                        order.delegateType,
                        order.deadline,
                        order.currency,
                        order.dataMask,
                        item,
                        detail
                    );
                }
                function _run(
                    Market.Order memory order,
                    Market.SettleShared memory shared,
                    Market.SettleDetail memory detail
                ) internal virtual returns (uint256) {
                    uint256 nativeAmount = 0;
                    Market.OrderItem memory item = order.items[detail.itemIdx];
                    bytes32 itemHash = _hashItem(order, item);
                    {
                        require(itemHash == detail.itemHash, 'item hash does not match');
                        require(order.network == block.chainid, 'wrong network');
                        require(
                            address(detail.executionDelegate) != address(0) &&
                                delegates[address(detail.executionDelegate)],
                            'unknown delegate'
                        );
                    }
                    bytes memory data = item.data;
                    {
                        if (order.dataMask.length > 0 && detail.dataReplacement.length > 0) {
                            _arrayReplace(data, detail.dataReplacement, order.dataMask);
                        }
                    }
                    if (detail.op == Market.Op.COMPLETE_SELL_OFFER) {
                        require(inventoryStatus[itemHash] == Market.InvStatus.NEW, 'order already exists');
                        require(order.intent == Market.INTENT_SELL, 'intent != sell');
                        _assertDelegation(order, detail);
                        require(order.deadline > block.timestamp, 'deadline reached');
                        require(detail.price >= item.price, 'underpaid');
                        nativeAmount = _takePayment(itemHash, order.currency, shared.user, detail.price);
                        require(
                            detail.executionDelegate.executeSell(order.user, shared.user, data),
                            'delegation error'
                        );
                        _distributeFeeAndProfit(
                            itemHash,
                            order.user,
                            order.currency,
                            detail,
                            detail.price,
                            detail.price
                        );
                        inventoryStatus[itemHash] = Market.InvStatus.COMPLETE;
                    } else if (detail.op == Market.Op.COMPLETE_BUY_OFFER) {
                        require(inventoryStatus[itemHash] == Market.InvStatus.NEW, 'order already exists');
                        require(order.intent == Market.INTENT_BUY, 'intent != buy');
                        _assertDelegation(order, detail);
                        require(order.deadline > block.timestamp, 'deadline reached');
                        require(item.price == detail.price, 'price not match');
                        require(!_isNative(order.currency), 'native token not supported');
                        nativeAmount = _takePayment(itemHash, order.currency, order.user, detail.price);
                        require(
                            detail.executionDelegate.executeBuy(shared.user, order.user, data),
                            'delegation error'
                        );
                        _distributeFeeAndProfit(
                            itemHash,
                            shared.user,
                            order.currency,
                            detail,
                            detail.price,
                            detail.price
                        );
                        inventoryStatus[itemHash] = Market.InvStatus.COMPLETE;
                    } else if (detail.op == Market.Op.CANCEL_OFFER) {
                        require(inventoryStatus[itemHash] == Market.InvStatus.NEW, 'unable to cancel');
                        require(order.deadline > block.timestamp, 'deadline reached');
                        inventoryStatus[itemHash] = Market.InvStatus.CANCELLED;
                        emit EvCancel(itemHash);
                    } else if (detail.op == Market.Op.BID) {
                        require(order.intent == Market.INTENT_AUCTION, 'intent != auction');
                        _assertDelegation(order, detail);
                        bool firstBid = false;
                        if (ongoingAuctions[itemHash].bidder == address(0)) {
                            require(inventoryStatus[itemHash] == Market.InvStatus.NEW, 'order already exists');
                            require(order.deadline > block.timestamp, 'auction ended');
                            require(detail.price >= item.price, 'underpaid');
                            firstBid = true;
                            ongoingAuctions[itemHash] = Market.OngoingAuction({
                                price: detail.price,
                                netPrice: detail.price,
                                bidder: shared.user,
                                endAt: order.deadline
                            });
                            inventoryStatus[itemHash] = Market.InvStatus.AUCTION;
                            require(
                                detail.executionDelegate.executeBid(order.user, address(0), shared.user, data),
                                'delegation error'
                            );
                        }
                        Market.OngoingAuction storage auc = ongoingAuctions[itemHash];
                        require(auc.endAt > block.timestamp, 'auction ended');
                        nativeAmount = _takePayment(itemHash, order.currency, shared.user, detail.price);
                        if (!firstBid) {
                            require(
                                inventoryStatus[itemHash] == Market.InvStatus.AUCTION,
                                'order is not auction'
                            );
                            require(
                                detail.price - auc.price >= (auc.price * detail.aucMinIncrementPct) / RATE_BASE,
                                'underbid'
                            );
                            uint256 bidRefund = auc.netPrice;
                            uint256 incentive = (detail.price * detail.bidIncentivePct) / RATE_BASE;
                            if (bidRefund + incentive > 0) {
                                _transferTo(order.currency, auc.bidder, bidRefund + incentive);
                                emit EvAuctionRefund(
                                    itemHash,
                                    address(order.currency),
                                    auc.bidder,
                                    bidRefund,
                                    incentive
                                );
                            }
                            require(
                                detail.executionDelegate.executeBid(order.user, auc.bidder, shared.user, data),
                                'delegation error'
                            );
                            auc.price = detail.price;
                            auc.netPrice = detail.price - incentive;
                            auc.bidder = shared.user;
                        }
                        if (block.timestamp + detail.aucIncDurationSecs > auc.endAt) {
                            auc.endAt += detail.aucIncDurationSecs;
                        }
                    } else if (
                        detail.op == Market.Op.REFUND_AUCTION ||
                        detail.op == Market.Op.REFUND_AUCTION_STUCK_ITEM
                    ) {
                        require(
                            inventoryStatus[itemHash] == Market.InvStatus.AUCTION,
                            'cannot cancel non-auction order'
                        );
                        Market.OngoingAuction storage auc = ongoingAuctions[itemHash];
                        if (auc.netPrice > 0) {
                            _transferTo(order.currency, auc.bidder, auc.netPrice);
                            emit EvAuctionRefund(
                                itemHash,
                                address(order.currency),
                                auc.bidder,
                                auc.netPrice,
                                0
                            );
                        }
                        _assertDelegation(order, detail);
                        if (detail.op == Market.Op.REFUND_AUCTION) {
                            require(
                                detail.executionDelegate.executeAuctionRefund(order.user, auc.bidder, data),
                                'delegation error'
                            );
                        }
                        delete ongoingAuctions[itemHash];
                        inventoryStatus[itemHash] = Market.InvStatus.REFUNDED;
                    } else if (detail.op == Market.Op.COMPLETE_AUCTION) {
                        require(
                            inventoryStatus[itemHash] == Market.InvStatus.AUCTION,
                            'cannot complete non-auction order'
                        );
                        _assertDelegation(order, detail);
                        Market.OngoingAuction storage auc = ongoingAuctions[itemHash];
                        require(block.timestamp >= auc.endAt, 'auction not finished yet');
                        require(
                            detail.executionDelegate.executeAuctionComplete(order.user, auc.bidder, data),
                            'delegation error'
                        );
                        _distributeFeeAndProfit(
                            itemHash,
                            order.user,
                            order.currency,
                            detail,
                            auc.price,
                            auc.netPrice
                        );
                        inventoryStatus[itemHash] = Market.InvStatus.COMPLETE;
                        delete ongoingAuctions[itemHash];
                    } else {
                        revert('unknown op');
                    }
                    _emitInventory(itemHash, order, item, shared, detail);
                    return nativeAmount;
                }
                function _assertDelegation(Market.Order memory order, Market.SettleDetail memory detail)
                    internal
                    view
                    virtual
                {
                    require(
                        detail.executionDelegate.delegateType() == order.delegateType,
                        'delegation type error'
                    );
                }
                // modifies `src`
                function _arrayReplace(
                    bytes memory src,
                    bytes memory replacement,
                    bytes memory mask
                ) internal view virtual {
                    require(src.length == replacement.length);
                    require(src.length == mask.length);
                    for (uint256 i = 0; i < src.length; i++) {
                        if (mask[i] != 0) {
                            src[i] = replacement[i];
                        }
                    }
                }
                function _verifyInputSignature(Market.RunInput memory input) internal view virtual {
                    bytes32 hash = keccak256(abi.encode(input.shared, input.details.length, input.details));
                    address signer = ECDSA.recover(hash, input.v, input.r, input.s);
                    require(signers[signer], 'Input signature error');
                }
                function _verifyOrderSignature(Market.Order memory order) internal view virtual {
                    address orderSigner;
                    if (order.signVersion == Market.SIGN_V1) {
                        bytes32 orderHash = keccak256(
                            abi.encode(
                                order.salt,
                                order.user,
                                order.network,
                                order.intent,
                                order.delegateType,
                                order.deadline,
                                order.currency,
                                order.dataMask,
                                order.items.length,
                                order.items
                            )
                        );
                        orderSigner = ECDSA.recover(
                            ECDSA.toEthSignedMessageHash(orderHash),
                            order.v,
                            order.r,
                            order.s
                        );
                    } else {
                        revert('unknown signature version');
                    }
                    require(orderSigner == order.user, 'Order signature does not match');
                }
                function _isNative(IERC20Upgradeable currency) internal view virtual returns (bool) {
                    return address(currency) == address(0);
                }
                function _takePayment(
                    bytes32 itemHash,
                    IERC20Upgradeable currency,
                    address from,
                    uint256 amount
                ) internal virtual returns (uint256) {
                    if (amount > 0) {
                        if (_isNative(currency)) {
                            return amount;
                        } else {
                            currency.safeTransferFrom(from, address(this), amount);
                        }
                    }
                    return 0;
                }
                function _transferTo(
                    IERC20Upgradeable currency,
                    address to,
                    uint256 amount
                ) internal virtual {
                    if (amount > 0) {
                        if (_isNative(currency)) {
                            AddressUpgradeable.sendValue(payable(to), amount);
                        } else {
                            currency.safeTransfer(to, amount);
                        }
                    }
                }
                function _distributeFeeAndProfit(
                    bytes32 itemHash,
                    address seller,
                    IERC20Upgradeable currency,
                    Market.SettleDetail memory sd,
                    uint256 price,
                    uint256 netPrice
                ) internal virtual {
                    require(price >= netPrice, 'price error');
                    uint256 payment = netPrice;
                    uint256 totalFeePct;
                    for (uint256 i = 0; i < sd.fees.length; i++) {
                        Market.Fee memory fee = sd.fees[i];
                        totalFeePct += fee.percentage;
                        uint256 amount = (price * fee.percentage) / RATE_BASE;
                        payment -= amount;
                        _transferTo(currency, fee.to, amount);
                    }
                    require(feeCapPct >= totalFeePct, 'total fee cap exceeded');
                    _transferTo(currency, seller, payment);
                    emit EvProfit(itemHash, address(currency), seller, payment);
                }
            }
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            interface IDelegate {
                function delegateType() external view returns (uint256);
                function executeSell(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external returns (bool);
                function executeBuy(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external returns (bool);
                function executeBid(
                    address seller,
                    address previousBidder,
                    address bidder,
                    bytes calldata data
                ) external returns (bool);
                function executeAuctionComplete(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external returns (bool);
                function executeAuctionRefund(
                    address seller,
                    address lastBidder,
                    bytes calldata data
                ) external returns (bool);
            }
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            import '@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol';
            interface IWETHUpgradable is IERC20Upgradeable {
                function deposit() external payable;
                function withdraw(uint256 wad) external;
            }
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            import './IDelegate.sol';
            import './IWETHUpgradable.sol';
            library Market {
                uint256 constant INTENT_SELL = 1;
                uint256 constant INTENT_AUCTION = 2;
                uint256 constant INTENT_BUY = 3;
                uint8 constant SIGN_V1 = 1;
                uint8 constant SIGN_V3 = 3;
                struct OrderItem {
                    uint256 price;
                    bytes data;
                }
                struct Order {
                    uint256 salt;
                    address user;
                    uint256 network;
                    uint256 intent;
                    uint256 delegateType;
                    uint256 deadline;
                    IERC20Upgradeable currency;
                    bytes dataMask;
                    OrderItem[] items;
                    // signature
                    bytes32 r;
                    bytes32 s;
                    uint8 v;
                    uint8 signVersion;
                }
                struct Fee {
                    uint256 percentage;
                    address to;
                }
                struct SettleDetail {
                    Market.Op op;
                    uint256 orderIdx;
                    uint256 itemIdx;
                    uint256 price;
                    bytes32 itemHash;
                    IDelegate executionDelegate;
                    bytes dataReplacement;
                    uint256 bidIncentivePct;
                    uint256 aucMinIncrementPct;
                    uint256 aucIncDurationSecs;
                    Fee[] fees;
                }
                struct SettleShared {
                    uint256 salt;
                    uint256 deadline;
                    uint256 amountToEth;
                    uint256 amountToWeth;
                    address user;
                    bool canFail;
                }
                struct RunInput {
                    Order[] orders;
                    SettleDetail[] details;
                    SettleShared shared;
                    // signature
                    bytes32 r;
                    bytes32 s;
                    uint8 v;
                }
                struct OngoingAuction {
                    uint256 price;
                    uint256 netPrice;
                    uint256 endAt;
                    address bidder;
                }
                enum InvStatus {
                    NEW,
                    AUCTION,
                    COMPLETE,
                    CANCELLED,
                    REFUNDED
                }
                enum Op {
                    INVALID,
                    // off-chain
                    COMPLETE_SELL_OFFER,
                    COMPLETE_BUY_OFFER,
                    CANCEL_OFFER,
                    // auction
                    BID,
                    COMPLETE_AUCTION,
                    REFUND_AUCTION,
                    REFUND_AUCTION_STUCK_ITEM
                }
                enum DelegationType {
                    INVALID,
                    ERC721,
                    ERC1155
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
            pragma solidity ^0.8.0;
            import "../utils/ContextUpgradeable.sol";
            import "../proxy/utils/Initializable.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 OwnableUpgradeable is Initializable, ContextUpgradeable {
                address private _owner;
                event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                /**
                 * @dev Initializes the contract setting the deployer as the initial owner.
                 */
                function __Ownable_init() internal onlyInitializing {
                    __Context_init_unchained();
                    __Ownable_init_unchained();
                }
                function __Ownable_init_unchained() internal onlyInitializing {
                    _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);
                }
                uint256[49] private __gap;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (proxy/utils/Initializable.sol)
            pragma solidity ^0.8.0;
            import "../../utils/AddressUpgradeable.sol";
            /**
             * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
             * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
             * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
             * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
             *
             * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
             * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
             *
             * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
             * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
             *
             * [CAUTION]
             * ====
             * Avoid leaving a contract uninitialized.
             *
             * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
             * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
             * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
             *
             * [.hljs-theme-light.nopadding]
             * ```
             * /// @custom:oz-upgrades-unsafe-allow constructor
             * constructor() initializer {}
             * ```
             * ====
             */
            abstract contract Initializable {
                /**
                 * @dev Indicates that the contract has been initialized.
                 */
                bool private _initialized;
                /**
                 * @dev Indicates that the contract is in the process of being initialized.
                 */
                bool private _initializing;
                /**
                 * @dev Modifier to protect an initializer function from being invoked twice.
                 */
                modifier initializer() {
                    // If the contract is initializing we ignore whether _initialized is set in order to support multiple
                    // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
                    // contract may have been reentered.
                    require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");
                    bool isTopLevelCall = !_initializing;
                    if (isTopLevelCall) {
                        _initializing = true;
                        _initialized = true;
                    }
                    _;
                    if (isTopLevelCall) {
                        _initializing = false;
                    }
                }
                /**
                 * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                 * {initializer} modifier, directly or indirectly.
                 */
                modifier onlyInitializing() {
                    require(_initializing, "Initializable: contract is not initializing");
                    _;
                }
                function _isConstructor() private view returns (bool) {
                    return !AddressUpgradeable.isContract(address(this));
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (security/Pausable.sol)
            pragma solidity ^0.8.0;
            import "../utils/ContextUpgradeable.sol";
            import "../proxy/utils/Initializable.sol";
            /**
             * @dev Contract module which allows children to implement an emergency stop
             * mechanism that can be triggered by an authorized account.
             *
             * This module is used through inheritance. It will make available the
             * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
             * the functions of your contract. Note that they will not be pausable by
             * simply including this module, only once the modifiers are put in place.
             */
            abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
                /**
                 * @dev Emitted when the pause is triggered by `account`.
                 */
                event Paused(address account);
                /**
                 * @dev Emitted when the pause is lifted by `account`.
                 */
                event Unpaused(address account);
                bool private _paused;
                /**
                 * @dev Initializes the contract in unpaused state.
                 */
                function __Pausable_init() internal onlyInitializing {
                    __Context_init_unchained();
                    __Pausable_init_unchained();
                }
                function __Pausable_init_unchained() internal onlyInitializing {
                    _paused = false;
                }
                /**
                 * @dev Returns true if the contract is paused, and false otherwise.
                 */
                function paused() public view virtual returns (bool) {
                    return _paused;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is not paused.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                modifier whenNotPaused() {
                    require(!paused(), "Pausable: paused");
                    _;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is paused.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                modifier whenPaused() {
                    require(paused(), "Pausable: not paused");
                    _;
                }
                /**
                 * @dev Triggers stopped state.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                function _pause() internal virtual whenNotPaused {
                    _paused = true;
                    emit Paused(_msgSender());
                }
                /**
                 * @dev Returns to normal state.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                function _unpause() internal virtual whenPaused {
                    _paused = false;
                    emit Unpaused(_msgSender());
                }
                uint256[49] private __gap;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
            pragma solidity ^0.8.0;
            import "../proxy/utils/Initializable.sol";
            /**
             * @dev Contract module that helps prevent reentrant calls to a function.
             *
             * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
             * available, which can be applied to functions to make sure there are no nested
             * (reentrant) calls to them.
             *
             * Note that because there is a single `nonReentrant` guard, functions marked as
             * `nonReentrant` may not call one another. This can be worked around by making
             * those functions `private`, and then adding `external` `nonReentrant` entry
             * points to them.
             *
             * TIP: If you would like to learn more about reentrancy and alternative ways
             * to protect against it, check out our blog post
             * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
             */
            abstract contract ReentrancyGuardUpgradeable is Initializable {
                // Booleans are more expensive than uint256 or any type that takes up a full
                // word because each write operation emits an extra SLOAD to first read the
                // slot's contents, replace the bits taken up by the boolean, and then write
                // back. This is the compiler's defense against contract upgrades and
                // pointer aliasing, and it cannot be disabled.
                // The values being non-zero value makes deployment a bit more expensive,
                // but in exchange the refund on every call to nonReentrant will be lower in
                // amount. Since refunds are capped to a percentage of the total
                // transaction's gas, it is best to keep them low in cases like this one, to
                // increase the likelihood of the full refund coming into effect.
                uint256 private constant _NOT_ENTERED = 1;
                uint256 private constant _ENTERED = 2;
                uint256 private _status;
                function __ReentrancyGuard_init() internal onlyInitializing {
                    __ReentrancyGuard_init_unchained();
                }
                function __ReentrancyGuard_init_unchained() internal onlyInitializing {
                    _status = _NOT_ENTERED;
                }
                /**
                 * @dev Prevents a contract from calling itself, directly or indirectly.
                 * Calling a `nonReentrant` function from another `nonReentrant`
                 * function is not supported. It is possible to prevent this from happening
                 * by making the `nonReentrant` function external, and making it call a
                 * `private` function that does the actual work.
                 */
                modifier nonReentrant() {
                    // On the first call to nonReentrant, _notEntered will be true
                    require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                    // Any calls to nonReentrant after this point will fail
                    _status = _ENTERED;
                    _;
                    // By storing the original value once again, a refund is triggered (see
                    // https://eips.ethereum.org/EIPS/eip-2200)
                    _status = _NOT_ENTERED;
                }
                uint256[49] private __gap;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
            pragma solidity ^0.8.0;
            import "../IERC20Upgradeable.sol";
            import "../../../utils/AddressUpgradeable.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 SafeERC20Upgradeable {
                using AddressUpgradeable for address;
                function safeTransfer(
                    IERC20Upgradeable token,
                    address to,
                    uint256 value
                ) internal {
                    _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                }
                function safeTransferFrom(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(IERC20Upgradeable 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 v4.4.1 (utils/cryptography/ECDSA.sol)
            pragma solidity ^0.8.0;
            import "../Strings.sol";
            /**
             * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
             *
             * These functions can be used to verify that a message was signed by the holder
             * of the private keys of a given address.
             */
            library ECDSA {
                enum RecoverError {
                    NoError,
                    InvalidSignature,
                    InvalidSignatureLength,
                    InvalidSignatureS,
                    InvalidSignatureV
                }
                function _throwError(RecoverError error) private pure {
                    if (error == RecoverError.NoError) {
                        return; // no error: do nothing
                    } else if (error == RecoverError.InvalidSignature) {
                        revert("ECDSA: invalid signature");
                    } else if (error == RecoverError.InvalidSignatureLength) {
                        revert("ECDSA: invalid signature length");
                    } else if (error == RecoverError.InvalidSignatureS) {
                        revert("ECDSA: invalid signature 's' value");
                    } else if (error == RecoverError.InvalidSignatureV) {
                        revert("ECDSA: invalid signature 'v' value");
                    }
                }
                /**
                 * @dev Returns the address that signed a hashed message (`hash`) with
                 * `signature` or error string. This address can then be used for verification purposes.
                 *
                 * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
                 * this function rejects them by requiring the `s` value to be in the lower
                 * half order, and the `v` value to be either 27 or 28.
                 *
                 * IMPORTANT: `hash` _must_ be the result of a hash operation for the
                 * verification to be secure: it is possible to craft signatures that
                 * recover to arbitrary addresses for non-hashed data. A safe way to ensure
                 * this is by receiving a hash of the original message (which may otherwise
                 * be too long), and then calling {toEthSignedMessageHash} on it.
                 *
                 * Documentation for signature generation:
                 * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
                 * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
                 *
                 * _Available since v4.3._
                 */
                function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
                    // Check the signature length
                    // - case 65: r,s,v signature (standard)
                    // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
                    if (signature.length == 65) {
                        bytes32 r;
                        bytes32 s;
                        uint8 v;
                        // ecrecover takes the signature parameters, and the only way to get them
                        // currently is to use assembly.
                        assembly {
                            r := mload(add(signature, 0x20))
                            s := mload(add(signature, 0x40))
                            v := byte(0, mload(add(signature, 0x60)))
                        }
                        return tryRecover(hash, v, r, s);
                    } else if (signature.length == 64) {
                        bytes32 r;
                        bytes32 vs;
                        // ecrecover takes the signature parameters, and the only way to get them
                        // currently is to use assembly.
                        assembly {
                            r := mload(add(signature, 0x20))
                            vs := mload(add(signature, 0x40))
                        }
                        return tryRecover(hash, r, vs);
                    } else {
                        return (address(0), RecoverError.InvalidSignatureLength);
                    }
                }
                /**
                 * @dev Returns the address that signed a hashed message (`hash`) with
                 * `signature`. This address can then be used for verification purposes.
                 *
                 * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
                 * this function rejects them by requiring the `s` value to be in the lower
                 * half order, and the `v` value to be either 27 or 28.
                 *
                 * IMPORTANT: `hash` _must_ be the result of a hash operation for the
                 * verification to be secure: it is possible to craft signatures that
                 * recover to arbitrary addresses for non-hashed data. A safe way to ensure
                 * this is by receiving a hash of the original message (which may otherwise
                 * be too long), and then calling {toEthSignedMessageHash} on it.
                 */
                function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
                    (address recovered, RecoverError error) = tryRecover(hash, signature);
                    _throwError(error);
                    return recovered;
                }
                /**
                 * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
                 *
                 * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
                 *
                 * _Available since v4.3._
                 */
                function tryRecover(
                    bytes32 hash,
                    bytes32 r,
                    bytes32 vs
                ) internal pure returns (address, RecoverError) {
                    bytes32 s;
                    uint8 v;
                    assembly {
                        s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                        v := add(shr(255, vs), 27)
                    }
                    return tryRecover(hash, v, r, s);
                }
                /**
                 * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
                 *
                 * _Available since v4.2._
                 */
                function recover(
                    bytes32 hash,
                    bytes32 r,
                    bytes32 vs
                ) internal pure returns (address) {
                    (address recovered, RecoverError error) = tryRecover(hash, r, vs);
                    _throwError(error);
                    return recovered;
                }
                /**
                 * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
                 * `r` and `s` signature fields separately.
                 *
                 * _Available since v4.3._
                 */
                function tryRecover(
                    bytes32 hash,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) internal pure returns (address, RecoverError) {
                    // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                    // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                    // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
                    // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                    //
                    // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                    // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                    // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                    // these malleable signatures as well.
                    if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
                        return (address(0), RecoverError.InvalidSignatureS);
                    }
                    if (v != 27 && v != 28) {
                        return (address(0), RecoverError.InvalidSignatureV);
                    }
                    // If the signature is valid (and not malleable), return the signer address
                    address signer = ecrecover(hash, v, r, s);
                    if (signer == address(0)) {
                        return (address(0), RecoverError.InvalidSignature);
                    }
                    return (signer, RecoverError.NoError);
                }
                /**
                 * @dev Overload of {ECDSA-recover} that receives the `v`,
                 * `r` and `s` signature fields separately.
                 */
                function recover(
                    bytes32 hash,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) internal pure returns (address) {
                    (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
                    _throwError(error);
                    return recovered;
                }
                /**
                 * @dev Returns an Ethereum Signed Message, created from a `hash`. This
                 * produces hash corresponding to the one signed with the
                 * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
                 * JSON-RPC method as part of EIP-191.
                 *
                 * See {recover}.
                 */
                function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
                    // 32 is the length in bytes of hash,
                    // enforced by the type signature above
                    return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
            32", hash));
                }
                /**
                 * @dev Returns an Ethereum Signed Message, created from `s`. This
                 * produces hash corresponding to the one signed with the
                 * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
                 * JSON-RPC method as part of EIP-191.
                 *
                 * See {recover}.
                 */
                function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
                    return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
            ", Strings.toString(s.length), s));
                }
                /**
                 * @dev Returns an Ethereum Signed Typed Data, created from a
                 * `domainSeparator` and a `structHash`. This produces hash corresponding
                 * to the one signed with the
                 * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
                 * JSON-RPC method as part of EIP-712.
                 *
                 * See {recover}.
                 */
                function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
                    return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
                }
            }
            // 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 IERC20Upgradeable {
                /**
                 * @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/Context.sol)
            pragma solidity ^0.8.0;
            import "../proxy/utils/Initializable.sol";
            /**
             * @dev Provides information about the current execution context, including the
             * sender of the transaction and its data. While these are generally available
             * via msg.sender and msg.data, they should not be accessed in such a direct
             * manner, since when dealing with meta-transactions the account sending and
             * paying for execution may not be the actual sender (as far as an application
             * is concerned).
             *
             * This contract is only required for intermediate, library-like contracts.
             */
            abstract contract ContextUpgradeable is Initializable {
                function __Context_init() internal onlyInitializing {
                    __Context_init_unchained();
                }
                function __Context_init_unchained() internal onlyInitializing {
                }
                function _msgSender() internal view virtual returns (address) {
                    return msg.sender;
                }
                function _msgData() internal view virtual returns (bytes calldata) {
                    return msg.data;
                }
                uint256[50] private __gap;
            }
            // 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 AddressUpgradeable {
                /**
                 * @dev Returns true if `account` is a contract.
                 *
                 * [IMPORTANT]
                 * ====
                 * It is unsafe to assume that an address for which this function returns
                 * false is an externally-owned account (EOA) and not a contract.
                 *
                 * Among others, `isContract` will return false for the following
                 * types of addresses:
                 *
                 *  - an externally-owned account
                 *  - a contract in construction
                 *  - an address where a contract will be created
                 *  - an address where a contract lived, but was destroyed
                 * ====
                 */
                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 Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                 * revert reason using the provided one.
                 *
                 * _Available since v4.3._
                 */
                function verifyCallResult(
                    bool success,
                    bytes memory returndata,
                    string memory errorMessage
                ) internal pure returns (bytes memory) {
                    if (success) {
                        return returndata;
                    } else {
                        // Look for revert reason and bubble it up if present
                        if (returndata.length > 0) {
                            // The easiest way to bubble the revert reason is using memory via assembly
                            assembly {
                                let returndata_size := mload(returndata)
                                revert(add(32, returndata), returndata_size)
                            }
                        } else {
                            revert(errorMessage);
                        }
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev String operations.
             */
            library Strings {
                bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                /**
                 * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                 */
                function toString(uint256 value) internal pure returns (string memory) {
                    // Inspired by OraclizeAPI's implementation - MIT licence
                    // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                    if (value == 0) {
                        return "0";
                    }
                    uint256 temp = value;
                    uint256 digits;
                    while (temp != 0) {
                        digits++;
                        temp /= 10;
                    }
                    bytes memory buffer = new bytes(digits);
                    while (value != 0) {
                        digits -= 1;
                        buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                        value /= 10;
                    }
                    return string(buffer);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                 */
                function toHexString(uint256 value) internal pure returns (string memory) {
                    if (value == 0) {
                        return "0x00";
                    }
                    uint256 temp = value;
                    uint256 length = 0;
                    while (temp != 0) {
                        length++;
                        temp >>= 8;
                    }
                    return toHexString(value, length);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                 */
                function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                    bytes memory buffer = new bytes(2 * length + 2);
                    buffer[0] = "0";
                    buffer[1] = "x";
                    for (uint256 i = 2 * length + 1; i > 1; --i) {
                        buffer[i] = _HEX_SYMBOLS[value & 0xf];
                        value >>= 4;
                    }
                    require(value == 0, "Strings: hex length insufficient");
                    return string(buffer);
                }
            }
            

            File 5 of 8: ERC721Delegate
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            import '@openzeppelin/contracts/token/ERC721/IERC721.sol';
            import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
            import '@openzeppelin/contracts/access/AccessControl.sol';
            import './MarketConsts.sol';
            import './IDelegate.sol';
            contract ERC721Delegate is IDelegate, AccessControl, IERC721Receiver {
                bytes32 public constant DELEGATION_CALLER = keccak256('DELEGATION_CALLER');
                struct Pair {
                    IERC721 token;
                    uint256 tokenId;
                }
                constructor() {
                    _grantRole(DEFAULT_ADMIN_ROLE, msg.sender);
                }
                function onERC721Received(
                    address,
                    address,
                    uint256,
                    bytes calldata
                ) external override returns (bytes4) {
                    return this.onERC721Received.selector;
                }
                function decode(bytes calldata data) internal pure returns (Pair[] memory) {
                    return abi.decode(data, (Pair[]));
                }
                function delegateType() external view returns (uint256) {
                    // return uint256(Market.DelegationType.ERC721);
                    return 1;
                }
                function executeSell(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external onlyRole(DELEGATION_CALLER) returns (bool) {
                    Pair[] memory pairs = decode(data);
                    for (uint256 i = 0; i < pairs.length; i++) {
                        Pair memory p = pairs[i];
                        p.token.safeTransferFrom(seller, buyer, p.tokenId);
                    }
                    return true;
                }
                function executeBuy(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external onlyRole(DELEGATION_CALLER) returns (bool) {
                    Pair[] memory pairs = decode(data);
                    for (uint256 i = 0; i < pairs.length; i++) {
                        Pair memory p = pairs[i];
                        p.token.safeTransferFrom(seller, buyer, p.tokenId);
                    }
                    return true;
                }
                function executeBid(
                    address seller,
                    address previousBidder,
                    address, // bidder,
                    bytes calldata data
                ) external onlyRole(DELEGATION_CALLER) returns (bool) {
                    if (previousBidder == address(0)) {
                        Pair[] memory pairs = decode(data);
                        for (uint256 i = 0; i < pairs.length; i++) {
                            Pair memory p = pairs[i];
                            p.token.safeTransferFrom(seller, address(this), p.tokenId);
                        }
                    }
                    return true;
                }
                function executeAuctionComplete(
                    address, // seller,
                    address buyer,
                    bytes calldata data
                ) external onlyRole(DELEGATION_CALLER) returns (bool) {
                    Pair[] memory pairs = decode(data);
                    for (uint256 i = 0; i < pairs.length; i++) {
                        Pair memory p = pairs[i];
                        p.token.safeTransferFrom(address(this), buyer, p.tokenId);
                    }
                    return true;
                }
                function executeAuctionRefund(
                    address seller,
                    address, // lastBidder,
                    bytes calldata data
                ) external onlyRole(DELEGATION_CALLER) returns (bool) {
                    Pair[] memory pairs = decode(data);
                    for (uint256 i = 0; i < pairs.length; i++) {
                        Pair memory p = pairs[i];
                        p.token.safeTransferFrom(address(this), seller, p.tokenId);
                    }
                    return true;
                }
                function transferBatch(Pair[] memory pairs, address to) public {
                    for (uint256 i = 0; i < pairs.length; i++) {
                        Pair memory p = pairs[i];
                        p.token.safeTransferFrom(msg.sender, to, p.tokenId);
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (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`, checking first that contract recipients
                 * are aware of the ERC721 protocol to prevent tokens from being forever locked.
                 *
                 * Requirements:
                 *
                 * - `from` cannot be the zero address.
                 * - `to` cannot be the zero address.
                 * - `tokenId` token must exist and be owned by `from`.
                 * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
                 * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                 *
                 * Emits a {Transfer} event.
                 */
                function safeTransferFrom(
                    address from,
                    address to,
                    uint256 tokenId
                ) external;
                /**
                 * @dev Transfers `tokenId` token from `from` to `to`.
                 *
                 * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
                 *
                 * Requirements:
                 *
                 * - `from` cannot be the zero address.
                 * - `to` cannot be the zero address.
                 * - `tokenId` token must be owned by `from`.
                 * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
                 *
                 * Emits a {Transfer} event.
                 */
                function transferFrom(
                    address from,
                    address to,
                    uint256 tokenId
                ) external;
                /**
                 * @dev Gives permission to `to` to transfer `tokenId` token to another account.
                 * The approval is cleared when the token is transferred.
                 *
                 * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
                 *
                 * Requirements:
                 *
                 * - The caller must own the token or be an approved operator.
                 * - `tokenId` must exist.
                 *
                 * Emits an {Approval} event.
                 */
                function approve(address to, uint256 tokenId) external;
                /**
                 * @dev Returns the account approved for `tokenId` token.
                 *
                 * Requirements:
                 *
                 * - `tokenId` must exist.
                 */
                function getApproved(uint256 tokenId) external view returns (address operator);
                /**
                 * @dev Approve or remove `operator` as an operator for the caller.
                 * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
                 *
                 * Requirements:
                 *
                 * - The `operator` cannot be the caller.
                 *
                 * Emits an {ApprovalForAll} event.
                 */
                function setApprovalForAll(address operator, bool _approved) external;
                /**
                 * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
                 *
                 * See {setApprovalForAll}
                 */
                function isApprovedForAll(address owner, address operator) external view returns (bool);
                /**
                 * @dev Safely transfers `tokenId` token from `from` to `to`.
                 *
                 * Requirements:
                 *
                 * - `from` cannot be the zero address.
                 * - `to` cannot be the zero address.
                 * - `tokenId` token must exist and be owned by `from`.
                 * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
                 * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                 *
                 * Emits a {Transfer} event.
                 */
                function safeTransferFrom(
                    address from,
                    address to,
                    uint256 tokenId,
                    bytes calldata data
                ) external;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)
            pragma solidity ^0.8.0;
            /**
             * @title ERC721 token receiver interface
             * @dev Interface for any contract that wants to support safeTransfers
             * from ERC721 asset contracts.
             */
            interface IERC721Receiver {
                /**
                 * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
                 * by `operator` from `from`, this function is called.
                 *
                 * It must return its Solidity selector to confirm the token transfer.
                 * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
                 *
                 * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
                 */
                function onERC721Received(
                    address operator,
                    address from,
                    uint256 tokenId,
                    bytes calldata data
                ) external returns (bytes4);
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (access/AccessControl.sol)
            pragma solidity ^0.8.0;
            import "./IAccessControl.sol";
            import "../utils/Context.sol";
            import "../utils/Strings.sol";
            import "../utils/introspection/ERC165.sol";
            /**
             * @dev Contract module that allows children to implement role-based access
             * control mechanisms. This is a lightweight version that doesn't allow enumerating role
             * members except through off-chain means by accessing the contract event logs. Some
             * applications may benefit from on-chain enumerability, for those cases see
             * {AccessControlEnumerable}.
             *
             * Roles are referred to by their `bytes32` identifier. These should be exposed
             * in the external API and be unique. The best way to achieve this is by
             * using `public constant` hash digests:
             *
             * ```
             * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
             * ```
             *
             * Roles can be used to represent a set of permissions. To restrict access to a
             * function call, use {hasRole}:
             *
             * ```
             * function foo() public {
             *     require(hasRole(MY_ROLE, msg.sender));
             *     ...
             * }
             * ```
             *
             * Roles can be granted and revoked dynamically via the {grantRole} and
             * {revokeRole} functions. Each role has an associated admin role, and only
             * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
             *
             * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
             * that only accounts with this role will be able to grant or revoke other
             * roles. More complex role relationships can be created by using
             * {_setRoleAdmin}.
             *
             * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
             * grant and revoke this role. Extra precautions should be taken to secure
             * accounts that have been granted it.
             */
            abstract contract AccessControl is Context, IAccessControl, ERC165 {
                struct RoleData {
                    mapping(address => bool) members;
                    bytes32 adminRole;
                }
                mapping(bytes32 => RoleData) private _roles;
                bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
                /**
                 * @dev Modifier that checks that an account has a specific role. Reverts
                 * with a standardized message including the required role.
                 *
                 * The format of the revert reason is given by the following regular expression:
                 *
                 *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
                 *
                 * _Available since v4.1._
                 */
                modifier onlyRole(bytes32 role) {
                    _checkRole(role, _msgSender());
                    _;
                }
                /**
                 * @dev See {IERC165-supportsInterface}.
                 */
                function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                    return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
                }
                /**
                 * @dev Returns `true` if `account` has been granted `role`.
                 */
                function hasRole(bytes32 role, address account) public view override returns (bool) {
                    return _roles[role].members[account];
                }
                /**
                 * @dev Revert with a standard message if `account` is missing `role`.
                 *
                 * The format of the revert reason is given by the following regular expression:
                 *
                 *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
                 */
                function _checkRole(bytes32 role, address account) internal view {
                    if (!hasRole(role, account)) {
                        revert(
                            string(
                                abi.encodePacked(
                                    "AccessControl: account ",
                                    Strings.toHexString(uint160(account), 20),
                                    " is missing role ",
                                    Strings.toHexString(uint256(role), 32)
                                )
                            )
                        );
                    }
                }
                /**
                 * @dev Returns the admin role that controls `role`. See {grantRole} and
                 * {revokeRole}.
                 *
                 * To change a role's admin, use {_setRoleAdmin}.
                 */
                function getRoleAdmin(bytes32 role) public view override returns (bytes32) {
                    return _roles[role].adminRole;
                }
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * If `account` had not been already granted `role`, emits a {RoleGranted}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                    _grantRole(role, account);
                }
                /**
                 * @dev Revokes `role` from `account`.
                 *
                 * If `account` had been granted `role`, emits a {RoleRevoked} event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                    _revokeRole(role, account);
                }
                /**
                 * @dev Revokes `role` from the calling account.
                 *
                 * Roles are often managed via {grantRole} and {revokeRole}: this function's
                 * purpose is to provide a mechanism for accounts to lose their privileges
                 * if they are compromised (such as when a trusted device is misplaced).
                 *
                 * If the calling account had been revoked `role`, emits a {RoleRevoked}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must be `account`.
                 */
                function renounceRole(bytes32 role, address account) public virtual override {
                    require(account == _msgSender(), "AccessControl: can only renounce roles for self");
                    _revokeRole(role, account);
                }
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * If `account` had not been already granted `role`, emits a {RoleGranted}
                 * event. Note that unlike {grantRole}, this function doesn't perform any
                 * checks on the calling account.
                 *
                 * [WARNING]
                 * ====
                 * This function should only be called from the constructor when setting
                 * up the initial roles for the system.
                 *
                 * Using this function in any other way is effectively circumventing the admin
                 * system imposed by {AccessControl}.
                 * ====
                 *
                 * NOTE: This function is deprecated in favor of {_grantRole}.
                 */
                function _setupRole(bytes32 role, address account) internal virtual {
                    _grantRole(role, account);
                }
                /**
                 * @dev Sets `adminRole` as ``role``'s admin role.
                 *
                 * Emits a {RoleAdminChanged} event.
                 */
                function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
                    bytes32 previousAdminRole = getRoleAdmin(role);
                    _roles[role].adminRole = adminRole;
                    emit RoleAdminChanged(role, previousAdminRole, adminRole);
                }
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * Internal function without access restriction.
                 */
                function _grantRole(bytes32 role, address account) internal virtual {
                    if (!hasRole(role, account)) {
                        _roles[role].members[account] = true;
                        emit RoleGranted(role, account, _msgSender());
                    }
                }
                /**
                 * @dev Revokes `role` from `account`.
                 *
                 * Internal function without access restriction.
                 */
                function _revokeRole(bytes32 role, address account) internal virtual {
                    if (hasRole(role, account)) {
                        _roles[role].members[account] = false;
                        emit RoleRevoked(role, account, _msgSender());
                    }
                }
            }
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            import './IDelegate.sol';
            import './IWETHUpgradable.sol';
            library Market {
                uint256 constant INTENT_SELL = 1;
                uint256 constant INTENT_AUCTION = 2;
                uint256 constant INTENT_BUY = 3;
                uint8 constant SIGN_V1 = 1;
                uint8 constant SIGN_V3 = 3;
                struct OrderItem {
                    uint256 price;
                    bytes data;
                }
                struct Order {
                    uint256 salt;
                    address user;
                    uint256 network;
                    uint256 intent;
                    uint256 delegateType;
                    uint256 deadline;
                    IERC20Upgradeable currency;
                    bytes dataMask;
                    OrderItem[] items;
                    // signature
                    bytes32 r;
                    bytes32 s;
                    uint8 v;
                    uint8 signVersion;
                }
                struct Fee {
                    uint256 percentage;
                    address to;
                }
                struct SettleDetail {
                    Market.Op op;
                    uint256 orderIdx;
                    uint256 itemIdx;
                    uint256 price;
                    bytes32 itemHash;
                    IDelegate executionDelegate;
                    bytes dataReplacement;
                    uint256 bidIncentivePct;
                    uint256 aucMinIncrementPct;
                    uint256 aucIncDurationSecs;
                    Fee[] fees;
                }
                struct SettleShared {
                    uint256 salt;
                    uint256 deadline;
                    uint256 amountToEth;
                    uint256 amountToWeth;
                    address user;
                    bool canFail;
                }
                struct RunInput {
                    Order[] orders;
                    SettleDetail[] details;
                    SettleShared shared;
                    // signature
                    bytes32 r;
                    bytes32 s;
                    uint8 v;
                }
                struct OngoingAuction {
                    uint256 price;
                    uint256 netPrice;
                    uint256 endAt;
                    address bidder;
                }
                enum InvStatus {
                    NEW,
                    AUCTION,
                    COMPLETE,
                    CANCELLED,
                    REFUNDED
                }
                enum Op {
                    INVALID,
                    // off-chain
                    COMPLETE_SELL_OFFER,
                    COMPLETE_BUY_OFFER,
                    CANCEL_OFFER,
                    // auction
                    BID,
                    COMPLETE_AUCTION,
                    REFUND_AUCTION,
                    REFUND_AUCTION_STUCK_ITEM
                }
                enum DelegationType {
                    INVALID,
                    ERC721,
                    ERC1155
                }
            }
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            interface IDelegate {
                function delegateType() external view returns (uint256);
                function executeSell(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external returns (bool);
                function executeBuy(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external returns (bool);
                function executeBid(
                    address seller,
                    address previousBidder,
                    address bidder,
                    bytes calldata data
                ) external returns (bool);
                function executeAuctionComplete(
                    address seller,
                    address buyer,
                    bytes calldata data
                ) external returns (bool);
                function executeAuctionRefund(
                    address seller,
                    address lastBidder,
                    bytes calldata data
                ) external returns (bool);
            }
            // 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
            // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev External interface of AccessControl declared to support ERC165 detection.
             */
            interface IAccessControl {
                /**
                 * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
                 *
                 * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
                 * {RoleAdminChanged} not being emitted signaling this.
                 *
                 * _Available since v3.1._
                 */
                event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
                /**
                 * @dev Emitted when `account` is granted `role`.
                 *
                 * `sender` is the account that originated the contract call, an admin role
                 * bearer except when using {AccessControl-_setupRole}.
                 */
                event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
                /**
                 * @dev Emitted when `account` is revoked `role`.
                 *
                 * `sender` is the account that originated the contract call:
                 *   - if using `revokeRole`, it is the admin role bearer
                 *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
                 */
                event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
                /**
                 * @dev Returns `true` if `account` has been granted `role`.
                 */
                function hasRole(bytes32 role, address account) external view returns (bool);
                /**
                 * @dev Returns the admin role that controls `role`. See {grantRole} and
                 * {revokeRole}.
                 *
                 * To change a role's admin, use {AccessControl-_setRoleAdmin}.
                 */
                function getRoleAdmin(bytes32 role) external view returns (bytes32);
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * If `account` had not been already granted `role`, emits a {RoleGranted}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function grantRole(bytes32 role, address account) external;
                /**
                 * @dev Revokes `role` from `account`.
                 *
                 * If `account` had been granted `role`, emits a {RoleRevoked} event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function revokeRole(bytes32 role, address account) external;
                /**
                 * @dev Revokes `role` from the calling account.
                 *
                 * Roles are often managed via {grantRole} and {revokeRole}: this function's
                 * purpose is to provide a mechanism for accounts to lose their privileges
                 * if they are compromised (such as when a trusted device is misplaced).
                 *
                 * If the calling account had been granted `role`, emits a {RoleRevoked}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must be `account`.
                 */
                function renounceRole(bytes32 role, address account) external;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts 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 (utils/Strings.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev String operations.
             */
            library Strings {
                bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                /**
                 * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                 */
                function toString(uint256 value) internal pure returns (string memory) {
                    // Inspired by OraclizeAPI's implementation - MIT licence
                    // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                    if (value == 0) {
                        return "0";
                    }
                    uint256 temp = value;
                    uint256 digits;
                    while (temp != 0) {
                        digits++;
                        temp /= 10;
                    }
                    bytes memory buffer = new bytes(digits);
                    while (value != 0) {
                        digits -= 1;
                        buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                        value /= 10;
                    }
                    return string(buffer);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                 */
                function toHexString(uint256 value) internal pure returns (string memory) {
                    if (value == 0) {
                        return "0x00";
                    }
                    uint256 temp = value;
                    uint256 length = 0;
                    while (temp != 0) {
                        length++;
                        temp >>= 8;
                    }
                    return toHexString(value, length);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                 */
                function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                    bytes memory buffer = new bytes(2 * length + 2);
                    buffer[0] = "0";
                    buffer[1] = "x";
                    for (uint256 i = 2 * length + 1; i > 1; --i) {
                        buffer[i] = _HEX_SYMBOLS[value & 0xf];
                        value >>= 4;
                    }
                    require(value == 0, "Strings: hex length insufficient");
                    return string(buffer);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
            pragma solidity ^0.8.0;
            import "./IERC165.sol";
            /**
             * @dev Implementation of the {IERC165} interface.
             *
             * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
             * for the additional interface id that will be supported. For example:
             *
             * ```solidity
             * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
             *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
             * }
             * ```
             *
             * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
             */
            abstract contract ERC165 is IERC165 {
                /**
                 * @dev See {IERC165-supportsInterface}.
                 */
                function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                    return interfaceId == type(IERC165).interfaceId;
                }
            }
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            import '@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol';
            interface IWETHUpgradable is IERC20Upgradeable {
                function deposit() external payable;
                function withdraw(uint256 wad) external;
            }
            // 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 IERC20Upgradeable {
                /**
                 * @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);
            }
            

            File 6 of 8: WyvernProxyRegistry
            pragma solidity ^0.4.13;
            
            contract Ownable {
              address public owner;
            
            
              event OwnershipRenounced(address indexed previousOwner);
              event OwnershipTransferred(
                address indexed previousOwner,
                address indexed newOwner
              );
            
            
              /**
               * @dev The Ownable constructor sets the original `owner` of the contract to the sender
               * account.
               */
              constructor() public {
                owner = msg.sender;
              }
            
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                require(msg.sender == owner);
                _;
              }
            
              /**
               * @dev Allows the current owner to transfer control of the contract to a newOwner.
               * @param newOwner The address to transfer ownership to.
               */
              function transferOwnership(address newOwner) public onlyOwner {
                require(newOwner != address(0));
                emit OwnershipTransferred(owner, newOwner);
                owner = newOwner;
              }
            
              /**
               * @dev Allows the current owner to relinquish control of the contract.
               */
              function renounceOwnership() public onlyOwner {
                emit OwnershipRenounced(owner);
                owner = address(0);
              }
            }
            
            contract ERC20Basic {
              function totalSupply() public view returns (uint256);
              function balanceOf(address who) public view returns (uint256);
              function transfer(address to, uint256 value) public returns (bool);
              event Transfer(address indexed from, address indexed to, uint256 value);
            }
            
            contract ERC20 is ERC20Basic {
              function allowance(address owner, address spender)
                public view returns (uint256);
            
              function transferFrom(address from, address to, uint256 value)
                public returns (bool);
            
              function approve(address spender, uint256 value) public returns (bool);
              event Approval(
                address indexed owner,
                address indexed spender,
                uint256 value
              );
            }
            
            contract TokenRecipient {
                event ReceivedEther(address indexed sender, uint amount);
                event ReceivedTokens(address indexed from, uint256 value, address indexed token, bytes extraData);
            
                /**
                 * @dev Receive tokens and generate a log event
                 * @param from Address from which to transfer tokens
                 * @param value Amount of tokens to transfer
                 * @param token Address of token
                 * @param extraData Additional data to log
                 */
                function receiveApproval(address from, uint256 value, address token, bytes extraData) public {
                    ERC20 t = ERC20(token);
                    require(t.transferFrom(from, this, value));
                    emit ReceivedTokens(from, value, token, extraData);
                }
            
                /**
                 * @dev Receive Ether and generate a log event
                 */
                function () payable public {
                    emit ReceivedEther(msg.sender, msg.value);
                }
            }
            
            contract ProxyRegistry is Ownable {
            
                /* DelegateProxy implementation contract. Must be initialized. */
                address public delegateProxyImplementation;
            
                /* Authenticated proxies by user. */
                mapping(address => OwnableDelegateProxy) public proxies;
            
                /* Contracts pending access. */
                mapping(address => uint) public pending;
            
                /* Contracts allowed to call those proxies. */
                mapping(address => bool) public contracts;
            
                /* Delay period for adding an authenticated contract.
                   This mitigates a particular class of potential attack on the Wyvern DAO (which owns this registry) - if at any point the value of assets held by proxy contracts exceeded the value of half the WYV supply (votes in the DAO),
                   a malicious but rational attacker could buy half the Wyvern and grant themselves access to all the proxy contracts. A delay period renders this attack nonthreatening - given two weeks, if that happened, users would have
                   plenty of time to notice and transfer their assets.
                */
                uint public DELAY_PERIOD = 2 weeks;
            
                /**
                 * Start the process to enable access for specified contract. Subject to delay period.
                 *
                 * @dev ProxyRegistry owner only
                 * @param addr Address to which to grant permissions
                 */
                function startGrantAuthentication (address addr)
                    public
                    onlyOwner
                {
                    require(!contracts[addr] && pending[addr] == 0);
                    pending[addr] = now;
                }
            
                /**
                 * End the process to nable access for specified contract after delay period has passed.
                 *
                 * @dev ProxyRegistry owner only
                 * @param addr Address to which to grant permissions
                 */
                function endGrantAuthentication (address addr)
                    public
                    onlyOwner
                {
                    require(!contracts[addr] && pending[addr] != 0 && ((pending[addr] + DELAY_PERIOD) < now));
                    pending[addr] = 0;
                    contracts[addr] = true;
                }
            
                /**
                 * Revoke access for specified contract. Can be done instantly.
                 *
                 * @dev ProxyRegistry owner only
                 * @param addr Address of which to revoke permissions
                 */    
                function revokeAuthentication (address addr)
                    public
                    onlyOwner
                {
                    contracts[addr] = false;
                }
            
                /**
                 * Register a proxy contract with this registry
                 *
                 * @dev Must be called by the user which the proxy is for, creates a new AuthenticatedProxy
                 * @return New AuthenticatedProxy contract
                 */
                function registerProxy()
                    public
                    returns (OwnableDelegateProxy proxy)
                {
                    require(proxies[msg.sender] == address(0));
                    proxy = new OwnableDelegateProxy(msg.sender, delegateProxyImplementation, abi.encodeWithSignature("initialize(address,address)", msg.sender, address(this)));
                    proxies[msg.sender] = proxy;
                    return proxy;
                }
            
            }
            
            contract WyvernProxyRegistry is ProxyRegistry {
            
                string public constant name = "Project Wyvern Proxy Registry";
            
                /* Whether the initial auth address has been set. */
                bool public initialAddressSet = false;
            
                constructor ()
                    public
                {
                    delegateProxyImplementation = new AuthenticatedProxy();
                }
            
                /** 
                 * Grant authentication to the initial Exchange protocol contract
                 *
                 * @dev No delay, can only be called once - after that the standard registry process with a delay must be used
                 * @param authAddress Address of the contract to grant authentication
                 */
                function grantInitialAuthentication (address authAddress)
                    onlyOwner
                    public
                {
                    require(!initialAddressSet);
                    initialAddressSet = true;
                    contracts[authAddress] = true;
                }
            
            }
            
            contract OwnedUpgradeabilityStorage {
            
              // Current implementation
              address internal _implementation;
            
              // Owner of the contract
              address private _upgradeabilityOwner;
            
              /**
               * @dev Tells the address of the owner
               * @return the address of the owner
               */
              function upgradeabilityOwner() public view returns (address) {
                return _upgradeabilityOwner;
              }
            
              /**
               * @dev Sets the address of the owner
               */
              function setUpgradeabilityOwner(address newUpgradeabilityOwner) internal {
                _upgradeabilityOwner = newUpgradeabilityOwner;
              }
            
              /**
              * @dev Tells the address of the current implementation
              * @return address of the current implementation
              */
              function implementation() public view returns (address) {
                return _implementation;
              }
            
              /**
              * @dev Tells the proxy type (EIP 897)
              * @return Proxy type, 2 for forwarding proxy
              */
              function proxyType() public pure returns (uint256 proxyTypeId) {
                return 2;
              }
            }
            
            contract AuthenticatedProxy is TokenRecipient, OwnedUpgradeabilityStorage {
            
                /* Whether initialized. */
                bool initialized = false;
            
                /* Address which owns this proxy. */
                address public user;
            
                /* Associated registry with contract authentication information. */
                ProxyRegistry public registry;
            
                /* Whether access has been revoked. */
                bool public revoked;
            
                /* Delegate call could be used to atomically transfer multiple assets owned by the proxy contract with one order. */
                enum HowToCall { Call, DelegateCall }
            
                /* Event fired when the proxy access is revoked or unrevoked. */
                event Revoked(bool revoked);
            
                /**
                 * Initialize an AuthenticatedProxy
                 *
                 * @param addrUser Address of user on whose behalf this proxy will act
                 * @param addrRegistry Address of ProxyRegistry contract which will manage this proxy
                 */
                function initialize (address addrUser, ProxyRegistry addrRegistry)
                    public
                {
                    require(!initialized);
                    initialized = true;
                    user = addrUser;
                    registry = addrRegistry;
                }
            
                /**
                 * Set the revoked flag (allows a user to revoke ProxyRegistry access)
                 *
                 * @dev Can be called by the user only
                 * @param revoke Whether or not to revoke access
                 */
                function setRevoke(bool revoke)
                    public
                {
                    require(msg.sender == user);
                    revoked = revoke;
                    emit Revoked(revoke);
                }
            
                /**
                 * Execute a message call from the proxy contract
                 *
                 * @dev Can be called by the user, or by a contract authorized by the registry as long as the user has not revoked access
                 * @param dest Address to which the call will be sent
                 * @param howToCall Which kind of call to make
                 * @param calldata Calldata to send
                 * @return Result of the call (success or failure)
                 */
                function proxy(address dest, HowToCall howToCall, bytes calldata)
                    public
                    returns (bool result)
                {
                    require(msg.sender == user || (!revoked && registry.contracts(msg.sender)));
                    if (howToCall == HowToCall.Call) {
                        result = dest.call(calldata);
                    } else if (howToCall == HowToCall.DelegateCall) {
                        result = dest.delegatecall(calldata);
                    }
                    return result;
                }
            
                /**
                 * Execute a message call and assert success
                 * 
                 * @dev Same functionality as `proxy`, just asserts the return value
                 * @param dest Address to which the call will be sent
                 * @param howToCall What kind of call to make
                 * @param calldata Calldata to send
                 */
                function proxyAssert(address dest, HowToCall howToCall, bytes calldata)
                    public
                {
                    require(proxy(dest, howToCall, calldata));
                }
            
            }
            
            contract Proxy {
            
              /**
              * @dev Tells the address of the implementation where every call will be delegated.
              * @return address of the implementation to which it will be delegated
              */
              function implementation() public view returns (address);
            
              /**
              * @dev Tells the type of proxy (EIP 897)
              * @return Type of proxy, 2 for upgradeable proxy
              */
              function proxyType() public pure returns (uint256 proxyTypeId);
            
              /**
              * @dev Fallback function allowing to perform a delegatecall to the given implementation.
              * This function will return whatever the implementation call returns
              */
              function () payable public {
                address _impl = implementation();
                require(_impl != address(0));
            
                assembly {
                  let ptr := mload(0x40)
                  calldatacopy(ptr, 0, calldatasize)
                  let result := delegatecall(gas, _impl, ptr, calldatasize, 0, 0)
                  let size := returndatasize
                  returndatacopy(ptr, 0, size)
            
                  switch result
                  case 0 { revert(ptr, size) }
                  default { return(ptr, size) }
                }
              }
            }
            
            contract OwnedUpgradeabilityProxy is Proxy, OwnedUpgradeabilityStorage {
              /**
              * @dev Event to show ownership has been transferred
              * @param previousOwner representing the address of the previous owner
              * @param newOwner representing the address of the new owner
              */
              event ProxyOwnershipTransferred(address previousOwner, address newOwner);
            
              /**
              * @dev This event will be emitted every time the implementation gets upgraded
              * @param implementation representing the address of the upgraded implementation
              */
              event Upgraded(address indexed implementation);
            
              /**
              * @dev Upgrades the implementation address
              * @param implementation representing the address of the new implementation to be set
              */
              function _upgradeTo(address implementation) internal {
                require(_implementation != implementation);
                _implementation = implementation;
                emit Upgraded(implementation);
              }
            
              /**
              * @dev Throws if called by any account other than the owner.
              */
              modifier onlyProxyOwner() {
                require(msg.sender == proxyOwner());
                _;
              }
            
              /**
               * @dev Tells the address of the proxy owner
               * @return the address of the proxy owner
               */
              function proxyOwner() public view returns (address) {
                return upgradeabilityOwner();
              }
            
              /**
               * @dev Allows the current owner to transfer control of the contract to a newOwner.
               * @param newOwner The address to transfer ownership to.
               */
              function transferProxyOwnership(address newOwner) public onlyProxyOwner {
                require(newOwner != address(0));
                emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
                setUpgradeabilityOwner(newOwner);
              }
            
              /**
               * @dev Allows the upgradeability owner to upgrade the current implementation of the proxy.
               * @param implementation representing the address of the new implementation to be set.
               */
              function upgradeTo(address implementation) public onlyProxyOwner {
                _upgradeTo(implementation);
              }
            
              /**
               * @dev Allows the upgradeability owner to upgrade the current implementation of the proxy
               * and delegatecall the new implementation for initialization.
               * @param implementation representing the address of the new implementation to be set.
               * @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
               * signature of the implementation to be called with the needed payload
               */
              function upgradeToAndCall(address implementation, bytes data) payable public onlyProxyOwner {
                upgradeTo(implementation);
                require(address(this).delegatecall(data));
              }
            }
            
            contract OwnableDelegateProxy is OwnedUpgradeabilityProxy {
            
                constructor(address owner, address initialImplementation, bytes calldata)
                    public
                {
                    setUpgradeabilityOwner(owner);
                    _upgradeTo(initialImplementation);
                    require(initialImplementation.delegatecall(calldata));
                }
            
            }

            File 7 of 8: FeeManagement
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import './TokenSplitter.sol';
            import './FeeSharingSetter.sol';
            import './IWETH.sol';
            import '@openzeppelin/contracts/access/AccessControl.sol';
            import '@openzeppelin/contracts/access/Ownable.sol';
            import '@openzeppelin/contracts/security/Pausable.sol';
            import '@openzeppelin/contracts/security/ReentrancyGuard.sol';
            import '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';
            import '@openzeppelin/contracts/utils/Address.sol';
            contract FeeManagement is AccessControl, Pausable, ReentrancyGuard {
                using SafeERC20 for IERC20;
                using SafeERC20 for IWETH;
                bytes32 public constant OPERATOR_ROLE = keccak256('OPERATOR_ROLE');
                TokenSplitter public immutable tokenSplitter;
                FeeSharingSetter public immutable feeSetter;
                IWETH public immutable weth;
                constructor(
                    TokenSplitter tokenSplitter_,
                    FeeSharingSetter feeSetter_,
                    IWETH weth_,
                    address operator_,
                    address admin_
                ) {
                    tokenSplitter = tokenSplitter_;
                    feeSetter = feeSetter_;
                    weth = weth_;
                    if (admin_ == address(0)) {
                        admin_ = msg.sender;
                    }
                    _grantRole(DEFAULT_ADMIN_ROLE, admin_);
                    _grantRole(OPERATOR_ROLE, admin_);
                    if (operator_ != address(0)) {
                        _grantRole(OPERATOR_ROLE, operator_);
                    }
                }
                receive() external payable {}
                function pause() external onlyRole(DEFAULT_ADMIN_ROLE) {
                    _pause();
                }
                function unpause() external onlyRole(DEFAULT_ADMIN_ROLE) {
                    _unpause();
                }
                // withdraw tokens
                function withdraw(address to, IERC20[] calldata tokens)
                    external
                    nonReentrant
                    whenNotPaused
                    onlyRole(DEFAULT_ADMIN_ROLE)
                {
                    require(to != address(0), 'Withdraw: address(0) cannot be recipient');
                    for (uint256 i = 0; i < tokens.length; i++) {
                        IERC20 currency = tokens[i];
                        if (address(currency) == address(0)) {
                            uint256 balance = address(this).balance;
                            if (balance > 0) {
                                Address.sendValue(payable(to), balance);
                            }
                        } else {
                            uint256 balance = currency.balanceOf(address(this));
                            if (balance > 0) {
                                currency.safeTransfer(to, balance);
                            }
                        }
                    }
                }
                function canRelease() external view returns (bool) {
                    return
                        block.number >
                        feeSetter.rewardDurationInBlocks() + feeSetter.lastRewardDistributionBlock();
                }
                function releaseAndUpdateReward(IERC20[] memory tokens, address[] memory accounts)
                    external
                    nonReentrant
                    whenNotPaused
                    onlyRole(OPERATOR_ROLE)
                {
                    _release(tokens);
                    // release x2y2 to pools, skipped when the balance is less than 1 token (the release can be called by anyone)
                    if (tokenSplitter.x2y2Token().balanceOf(address(tokenSplitter)) >= 1 ether) {
                        for (uint256 i = 0; i < accounts.length; i++) {
                            tokenSplitter.releaseTokens(accounts[i]);
                        }
                    }
                    feeSetter.updateRewards();
                }
                function release(IERC20[] memory tokens)
                    external
                    nonReentrant
                    whenNotPaused
                    onlyRole(OPERATOR_ROLE)
                {
                    _release(tokens);
                }
                function _release(IERC20[] memory tokens) internal {
                    uint256 balance = address(this).balance;
                    if (balance > 0) {
                        weth.deposit{value: balance}();
                    }
                    balance = weth.balanceOf(address(this));
                    if (balance > 0) {
                        weth.safeTransfer(address(feeSetter), balance);
                    }
                    for (uint256 i = 0; i < tokens.length; i++) {
                        IERC20 currency = tokens[i];
                        balance = currency.balanceOf(address(this));
                        if (balance > 0) {
                            currency.safeTransfer(address(feeSetter), balance);
                        }
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            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';
            /**
             * @title TokenSplitter
             * @notice It splits X2Y2 to team/treasury/trading volume reward accounts based on shares.
             */
            contract TokenSplitter is Ownable, ReentrancyGuard {
                using SafeERC20 for IERC20;
                struct AccountInfo {
                    uint256 shares;
                    uint256 tokensDistributedToAccount;
                }
                uint256 public immutable TOTAL_SHARES;
                IERC20 public immutable x2y2Token;
                // Total tokens distributed across all accounts
                uint256 public totalTokensDistributed;
                mapping(address => AccountInfo) public accountInfo;
                event NewSharesOwner(address indexed oldRecipient, address indexed newRecipient);
                event TokensTransferred(address indexed account, uint256 amount);
                /**
                 * @notice Constructor
                 * @param _accounts array of accounts addresses
                 * @param _shares array of shares per account
                 * @param _x2y2Token address of the X2Y2 token
                 */
                constructor(
                    address[] memory _accounts,
                    uint256[] memory _shares,
                    address _x2y2Token
                ) {
                    require(_accounts.length == _shares.length, 'Splitter: Length differ');
                    require(_accounts.length > 0, 'Splitter: Length must be > 0');
                    uint256 currentShares;
                    for (uint256 i = 0; i < _accounts.length; i++) {
                        require(_shares[i] > 0, 'Splitter: Shares are 0');
                        currentShares += _shares[i];
                        accountInfo[_accounts[i]].shares = _shares[i];
                    }
                    TOTAL_SHARES = currentShares;
                    x2y2Token = IERC20(_x2y2Token);
                }
                /**
                 * @notice Release X2Y2 tokens to the account
                 * @param account address of the account
                 */
                function releaseTokens(address account) external nonReentrant {
                    require(accountInfo[account].shares > 0, 'Splitter: Account has no share');
                    // Calculate amount to transfer to the account
                    uint256 totalTokensReceived = x2y2Token.balanceOf(address(this)) + totalTokensDistributed;
                    uint256 pendingRewards = ((totalTokensReceived * accountInfo[account].shares) /
                        TOTAL_SHARES) - accountInfo[account].tokensDistributedToAccount;
                    // Revert if equal to 0
                    require(pendingRewards != 0, 'Splitter: Nothing to transfer');
                    accountInfo[account].tokensDistributedToAccount += pendingRewards;
                    totalTokensDistributed += pendingRewards;
                    // Transfer funds to account
                    x2y2Token.safeTransfer(account, pendingRewards);
                    emit TokensTransferred(account, pendingRewards);
                }
                /**
                 * @notice Update share recipient
                 * @param _newRecipient address of the new recipient
                 * @param _currentRecipient address of the current recipient
                 */
                function updateSharesOwner(address _newRecipient, address _currentRecipient)
                    external
                    onlyOwner
                {
                    require(
                        accountInfo[_currentRecipient].shares > 0,
                        'Owner: Current recipient has no shares'
                    );
                    require(accountInfo[_newRecipient].shares == 0, 'Owner: New recipient has existing shares');
                    // Copy shares to new recipient
                    accountInfo[_newRecipient].shares = accountInfo[_currentRecipient].shares;
                    accountInfo[_newRecipient].tokensDistributedToAccount = accountInfo[_currentRecipient]
                        .tokensDistributedToAccount;
                    // Reset existing shares
                    accountInfo[_currentRecipient].shares = 0;
                    accountInfo[_currentRecipient].tokensDistributedToAccount = 0;
                    emit NewSharesOwner(_currentRecipient, _newRecipient);
                }
                /**
                 * @notice Retrieve amount of X2Y2 tokens that can be transferred
                 * @param account address of the account
                 */
                function calculatePendingRewards(address account) external view returns (uint256) {
                    if (accountInfo[account].shares == 0) {
                        return 0;
                    }
                    uint256 totalTokensReceived = x2y2Token.balanceOf(address(this)) + totalTokensDistributed;
                    uint256 pendingRewards = ((totalTokensReceived * accountInfo[account].shares) /
                        TOTAL_SHARES) - accountInfo[account].tokensDistributedToAccount;
                    return pendingRewards;
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import {AccessControl} from '@openzeppelin/contracts/access/AccessControl.sol';
            import {ReentrancyGuard} from '@openzeppelin/contracts/security/ReentrancyGuard.sol';
            import {IERC20, SafeERC20} from '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';
            import {EnumerableSet} from '@openzeppelin/contracts/utils/structs/EnumerableSet.sol';
            import {FeeSharingSystem} from './FeeSharingSystem.sol';
            import {TokenDistributor} from './TokenDistributor.sol';
            import {IRewardConvertor} from './IRewardConvertor.sol';
            import {IMintableERC20} from './IMintableERC20.sol';
            import {ITokenStaked} from './ITokenStaked.sol';
            /**
             * @title FeeSharingSetter
             * @notice It receives exchange fees and owns the FeeSharingSystem contract.
             * It can plug to AMMs for converting all received currencies to WETH.
             */
            contract FeeSharingSetter is ReentrancyGuard, AccessControl {
                using EnumerableSet for EnumerableSet.AddressSet;
                using SafeERC20 for IERC20;
                // Operator role
                bytes32 public constant OPERATOR_ROLE = keccak256('OPERATOR_ROLE');
                // Min duration for each fee-sharing period (in blocks)
                uint256 public immutable MIN_REWARD_DURATION_IN_BLOCKS;
                // Max duration for each fee-sharing period (in blocks)
                uint256 public immutable MAX_REWARD_DURATION_IN_BLOCKS;
                IERC20 public immutable x2y2Token;
                IERC20 public immutable rewardToken;
                FeeSharingSystem public feeSharingSystem;
                TokenDistributor public immutable tokenDistributor;
                // Reward convertor (tool to convert other currencies to rewardToken)
                IRewardConvertor public rewardConvertor;
                // Last reward block of distribution
                uint256 public lastRewardDistributionBlock;
                // Next reward duration in blocks
                uint256 public nextRewardDurationInBlocks;
                // Reward duration in blocks
                uint256 public rewardDurationInBlocks;
                // Set of addresses that are staking only the fee sharing
                EnumerableSet.AddressSet private _feeStakingAddresses;
                mapping(address => bool) public feeStakingAddressIStaked;
                event ConversionToRewardToken(
                    address indexed token,
                    uint256 amountConverted,
                    uint256 amountReceived
                );
                event FeeStakingAddressesAdded(address[] feeStakingAddresses);
                event FeeStakingAddressesRemoved(address[] feeStakingAddresses);
                event NewRewardDurationInBlocks(uint256 rewardDurationInBlocks);
                event NewRewardConvertor(address rewardConvertor);
                /**
                 * @notice Constructor
                 * @param _feeSharingSystem address of the fee sharing system
                 * @param _minRewardDurationInBlocks minimum reward duration in blocks
                 * @param _maxRewardDurationInBlocks maximum reward duration in blocks
                 * @param _rewardDurationInBlocks reward duration between two updates in blocks
                 */
                constructor(
                    address _feeSharingSystem,
                    uint256 _minRewardDurationInBlocks,
                    uint256 _maxRewardDurationInBlocks,
                    uint256 _rewardDurationInBlocks
                ) {
                    require(
                        (_rewardDurationInBlocks <= _maxRewardDurationInBlocks) &&
                            (_rewardDurationInBlocks >= _minRewardDurationInBlocks),
                        'Owner: Reward duration in blocks outside of range'
                    );
                    MIN_REWARD_DURATION_IN_BLOCKS = _minRewardDurationInBlocks;
                    MAX_REWARD_DURATION_IN_BLOCKS = _maxRewardDurationInBlocks;
                    feeSharingSystem = FeeSharingSystem(_feeSharingSystem);
                    rewardToken = feeSharingSystem.rewardToken();
                    x2y2Token = feeSharingSystem.x2y2Token();
                    tokenDistributor = feeSharingSystem.tokenDistributor();
                    rewardDurationInBlocks = _rewardDurationInBlocks;
                    nextRewardDurationInBlocks = _rewardDurationInBlocks;
                    _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
                }
                /**
                 * @notice Update the reward per block (in rewardToken)
                 * @dev It automatically retrieves the number of pending WETH and adjusts
                 * based on the balance of X2Y2 in fee-staking addresses that exist in the set.
                 */
                function updateRewards() external onlyRole(OPERATOR_ROLE) {
                    if (lastRewardDistributionBlock > 0) {
                        require(
                            block.number > (rewardDurationInBlocks + lastRewardDistributionBlock),
                            'Reward: Too early to add'
                        );
                    }
                    // Adjust for this period
                    if (rewardDurationInBlocks != nextRewardDurationInBlocks) {
                        rewardDurationInBlocks = nextRewardDurationInBlocks;
                    }
                    lastRewardDistributionBlock = block.number;
                    // Calculate the reward to distribute as the balance held by this address
                    uint256 reward = rewardToken.balanceOf(address(this));
                    require(reward != 0, 'Reward: Nothing to distribute');
                    // Check if there is any address eligible for fee-sharing only
                    uint256 numberAddressesForFeeStaking = _feeStakingAddresses.length();
                    // If there are eligible addresses for fee-sharing only, calculate their shares
                    if (numberAddressesForFeeStaking > 0) {
                        uint256[] memory x2y2Balances = new uint256[](numberAddressesForFeeStaking);
                        (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(feeSharingSystem));
                        for (uint256 i = 0; i < numberAddressesForFeeStaking; i++) {
                            address a = _feeStakingAddresses.at(i);
                            uint256 balance = x2y2Token.balanceOf(a);
                            if (feeStakingAddressIStaked[a]) {
                                balance = ITokenStaked(a).getTotalStaked();
                            }
                            totalAmountStaked += balance;
                            x2y2Balances[i] = balance;
                        }
                        // Only apply the logic if the totalAmountStaked > 0 (to prevent division by 0)
                        if (totalAmountStaked > 0) {
                            uint256 adjustedReward = reward;
                            for (uint256 i = 0; i < numberAddressesForFeeStaking; i++) {
                                uint256 amountToTransfer = (x2y2Balances[i] * reward) / totalAmountStaked;
                                if (amountToTransfer > 0) {
                                    adjustedReward -= amountToTransfer;
                                    rewardToken.safeTransfer(_feeStakingAddresses.at(i), amountToTransfer);
                                }
                            }
                            // Adjust reward accordingly
                            reward = adjustedReward;
                        }
                    }
                    // Transfer tokens to fee sharing system
                    rewardToken.safeTransfer(address(feeSharingSystem), reward);
                    // Update rewards
                    feeSharingSystem.updateRewards(reward, rewardDurationInBlocks);
                }
                /**
                 * @notice Convert currencies to reward token
                 * @dev Function only usable only for whitelisted currencies (where no potential side effect)
                 * @param token address of the token to sell
                 * @param additionalData additional data (e.g., slippage)
                 */
                function convertCurrencyToRewardToken(address token, bytes calldata additionalData)
                    external
                    nonReentrant
                    onlyRole(OPERATOR_ROLE)
                {
                    require(address(rewardConvertor) != address(0), 'Convert: RewardConvertor not set');
                    require(token != address(rewardToken), 'Convert: Cannot be reward token');
                    uint256 amountToConvert = IERC20(token).balanceOf(address(this));
                    require(amountToConvert != 0, 'Convert: Amount to convert must be > 0');
                    // Adjust allowance for this transaction only
                    IERC20(token).safeIncreaseAllowance(address(rewardConvertor), amountToConvert);
                    // Exchange token to reward token
                    uint256 amountReceived = rewardConvertor.convert(
                        token,
                        address(rewardToken),
                        amountToConvert,
                        additionalData
                    );
                    emit ConversionToRewardToken(token, amountToConvert, amountReceived);
                }
                /**
                 * @notice Add staking addresses
                 * @param _stakingAddresses array of addresses eligible for fee-sharing only
                 */
                function addFeeStakingAddresses(
                    address[] calldata _stakingAddresses,
                    bool[] calldata _addressIStaked
                ) external onlyRole(DEFAULT_ADMIN_ROLE) {
                    require(_stakingAddresses.length == _addressIStaked.length, 'Owner: param length error');
                    for (uint256 i = 0; i < _stakingAddresses.length; i++) {
                        require(
                            !_feeStakingAddresses.contains(_stakingAddresses[i]),
                            'Owner: Address already registered'
                        );
                        _feeStakingAddresses.add(_stakingAddresses[i]);
                        if (_addressIStaked[i]) {
                            feeStakingAddressIStaked[_stakingAddresses[i]] = true;
                        }
                    }
                    emit FeeStakingAddressesAdded(_stakingAddresses);
                }
                /**
                 * @notice Remove staking addresses
                 * @param _stakingAddresses array of addresses eligible for fee-sharing only
                 */
                function removeFeeStakingAddresses(address[] calldata _stakingAddresses)
                    external
                    onlyRole(DEFAULT_ADMIN_ROLE)
                {
                    for (uint256 i = 0; i < _stakingAddresses.length; i++) {
                        require(
                            _feeStakingAddresses.contains(_stakingAddresses[i]),
                            'Owner: Address not registered'
                        );
                        _feeStakingAddresses.remove(_stakingAddresses[i]);
                        if (feeStakingAddressIStaked[_stakingAddresses[i]]) {
                            delete feeStakingAddressIStaked[_stakingAddresses[i]];
                        }
                    }
                    emit FeeStakingAddressesRemoved(_stakingAddresses);
                }
                /**
                 * @notice Set new reward duration in blocks for next update
                 * @param _newRewardDurationInBlocks number of blocks for new reward period
                 */
                function setNewRewardDurationInBlocks(uint256 _newRewardDurationInBlocks)
                    external
                    onlyRole(DEFAULT_ADMIN_ROLE)
                {
                    require(
                        (_newRewardDurationInBlocks <= MAX_REWARD_DURATION_IN_BLOCKS) &&
                            (_newRewardDurationInBlocks >= MIN_REWARD_DURATION_IN_BLOCKS),
                        'Owner: New reward duration in blocks outside of range'
                    );
                    nextRewardDurationInBlocks = _newRewardDurationInBlocks;
                    emit NewRewardDurationInBlocks(_newRewardDurationInBlocks);
                }
                /**
                 * @notice Set reward convertor contract
                 * @param _rewardConvertor address of the reward convertor (set to null to deactivate)
                 */
                function setRewardConvertor(address _rewardConvertor) external onlyRole(DEFAULT_ADMIN_ROLE) {
                    rewardConvertor = IRewardConvertor(_rewardConvertor);
                    emit NewRewardConvertor(_rewardConvertor);
                }
                /**
                 * @notice See addresses eligible for fee-staking
                 */
                function viewFeeStakingAddresses() external view returns (address[] memory) {
                    uint256 length = _feeStakingAddresses.length();
                    address[] memory feeStakingAddresses = new address[](length);
                    for (uint256 i = 0; i < length; i++) {
                        feeStakingAddresses[i] = _feeStakingAddresses.at(i);
                    }
                    return (feeStakingAddresses);
                }
            }
            // SPDX-License-Identifier: Unlicensed
            pragma solidity ^0.8.0;
            pragma abicoder v2;
            import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
            interface IWETH is IERC20 {
                function deposit() external payable;
                function withdraw(uint256 wad) external;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (access/AccessControl.sol)
            pragma solidity ^0.8.0;
            import "./IAccessControl.sol";
            import "../utils/Context.sol";
            import "../utils/Strings.sol";
            import "../utils/introspection/ERC165.sol";
            /**
             * @dev Contract module that allows children to implement role-based access
             * control mechanisms. This is a lightweight version that doesn't allow enumerating role
             * members except through off-chain means by accessing the contract event logs. Some
             * applications may benefit from on-chain enumerability, for those cases see
             * {AccessControlEnumerable}.
             *
             * Roles are referred to by their `bytes32` identifier. These should be exposed
             * in the external API and be unique. The best way to achieve this is by
             * using `public constant` hash digests:
             *
             * ```
             * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
             * ```
             *
             * Roles can be used to represent a set of permissions. To restrict access to a
             * function call, use {hasRole}:
             *
             * ```
             * function foo() public {
             *     require(hasRole(MY_ROLE, msg.sender));
             *     ...
             * }
             * ```
             *
             * Roles can be granted and revoked dynamically via the {grantRole} and
             * {revokeRole} functions. Each role has an associated admin role, and only
             * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
             *
             * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
             * that only accounts with this role will be able to grant or revoke other
             * roles. More complex role relationships can be created by using
             * {_setRoleAdmin}.
             *
             * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
             * grant and revoke this role. Extra precautions should be taken to secure
             * accounts that have been granted it.
             */
            abstract contract AccessControl is Context, IAccessControl, ERC165 {
                struct RoleData {
                    mapping(address => bool) members;
                    bytes32 adminRole;
                }
                mapping(bytes32 => RoleData) private _roles;
                bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
                /**
                 * @dev Modifier that checks that an account has a specific role. Reverts
                 * with a standardized message including the required role.
                 *
                 * The format of the revert reason is given by the following regular expression:
                 *
                 *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
                 *
                 * _Available since v4.1._
                 */
                modifier onlyRole(bytes32 role) {
                    _checkRole(role, _msgSender());
                    _;
                }
                /**
                 * @dev See {IERC165-supportsInterface}.
                 */
                function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                    return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
                }
                /**
                 * @dev Returns `true` if `account` has been granted `role`.
                 */
                function hasRole(bytes32 role, address account) public view override returns (bool) {
                    return _roles[role].members[account];
                }
                /**
                 * @dev Revert with a standard message if `account` is missing `role`.
                 *
                 * The format of the revert reason is given by the following regular expression:
                 *
                 *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
                 */
                function _checkRole(bytes32 role, address account) internal view {
                    if (!hasRole(role, account)) {
                        revert(
                            string(
                                abi.encodePacked(
                                    "AccessControl: account ",
                                    Strings.toHexString(uint160(account), 20),
                                    " is missing role ",
                                    Strings.toHexString(uint256(role), 32)
                                )
                            )
                        );
                    }
                }
                /**
                 * @dev Returns the admin role that controls `role`. See {grantRole} and
                 * {revokeRole}.
                 *
                 * To change a role's admin, use {_setRoleAdmin}.
                 */
                function getRoleAdmin(bytes32 role) public view override returns (bytes32) {
                    return _roles[role].adminRole;
                }
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * If `account` had not been already granted `role`, emits a {RoleGranted}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                    _grantRole(role, account);
                }
                /**
                 * @dev Revokes `role` from `account`.
                 *
                 * If `account` had been granted `role`, emits a {RoleRevoked} event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                    _revokeRole(role, account);
                }
                /**
                 * @dev Revokes `role` from the calling account.
                 *
                 * Roles are often managed via {grantRole} and {revokeRole}: this function's
                 * purpose is to provide a mechanism for accounts to lose their privileges
                 * if they are compromised (such as when a trusted device is misplaced).
                 *
                 * If the calling account had been revoked `role`, emits a {RoleRevoked}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must be `account`.
                 */
                function renounceRole(bytes32 role, address account) public virtual override {
                    require(account == _msgSender(), "AccessControl: can only renounce roles for self");
                    _revokeRole(role, account);
                }
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * If `account` had not been already granted `role`, emits a {RoleGranted}
                 * event. Note that unlike {grantRole}, this function doesn't perform any
                 * checks on the calling account.
                 *
                 * [WARNING]
                 * ====
                 * This function should only be called from the constructor when setting
                 * up the initial roles for the system.
                 *
                 * Using this function in any other way is effectively circumventing the admin
                 * system imposed by {AccessControl}.
                 * ====
                 *
                 * NOTE: This function is deprecated in favor of {_grantRole}.
                 */
                function _setupRole(bytes32 role, address account) internal virtual {
                    _grantRole(role, account);
                }
                /**
                 * @dev Sets `adminRole` as ``role``'s admin role.
                 *
                 * Emits a {RoleAdminChanged} event.
                 */
                function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
                    bytes32 previousAdminRole = getRoleAdmin(role);
                    _roles[role].adminRole = adminRole;
                    emit RoleAdminChanged(role, previousAdminRole, adminRole);
                }
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * Internal function without access restriction.
                 */
                function _grantRole(bytes32 role, address account) internal virtual {
                    if (!hasRole(role, account)) {
                        _roles[role].members[account] = true;
                        emit RoleGranted(role, account, _msgSender());
                    }
                }
                /**
                 * @dev Revokes `role` from `account`.
                 *
                 * Internal function without access restriction.
                 */
                function _revokeRole(bytes32 role, address account) internal virtual {
                    if (hasRole(role, account)) {
                        _roles[role].members[account] = false;
                        emit RoleRevoked(role, account, _msgSender());
                    }
                }
            }
            // 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/Pausable.sol)
            pragma solidity ^0.8.0;
            import "../utils/Context.sol";
            /**
             * @dev Contract module which allows children to implement an emergency stop
             * mechanism that can be triggered by an authorized account.
             *
             * This module is used through inheritance. It will make available the
             * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
             * the functions of your contract. Note that they will not be pausable by
             * simply including this module, only once the modifiers are put in place.
             */
            abstract contract Pausable is Context {
                /**
                 * @dev Emitted when the pause is triggered by `account`.
                 */
                event Paused(address account);
                /**
                 * @dev Emitted when the pause is lifted by `account`.
                 */
                event Unpaused(address account);
                bool private _paused;
                /**
                 * @dev Initializes the contract in unpaused state.
                 */
                constructor() {
                    _paused = false;
                }
                /**
                 * @dev Returns true if the contract is paused, and false otherwise.
                 */
                function paused() public view virtual returns (bool) {
                    return _paused;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is not paused.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                modifier whenNotPaused() {
                    require(!paused(), "Pausable: paused");
                    _;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is paused.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                modifier whenPaused() {
                    require(paused(), "Pausable: not paused");
                    _;
                }
                /**
                 * @dev Triggers stopped state.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                function _pause() internal virtual whenNotPaused {
                    _paused = true;
                    emit Paused(_msgSender());
                }
                /**
                 * @dev Returns to normal state.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                function _unpause() internal virtual whenPaused {
                    _paused = false;
                    emit Unpaused(_msgSender());
                }
            }
            // 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
            // 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 (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/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;
            import {AccessControl} from '@openzeppelin/contracts/access/AccessControl.sol';
            import {IERC20, SafeERC20} from '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';
            import {ReentrancyGuard} from '@openzeppelin/contracts/security/ReentrancyGuard.sol';
            import {TokenDistributor} from './TokenDistributor.sol';
            import {IStakeFor} from './IStakeFor.sol';
            /**
             * @title FeeSharingSystem
             * @notice It handles the distribution of fees using
             * WETH along with the auto-compounding of X2Y2.
             */
            contract FeeSharingSystem is ReentrancyGuard, AccessControl, IStakeFor {
                using SafeERC20 for IERC20;
                // for `depositFor` call
                bytes32 public constant DEPOSIT_ROLE = keccak256('DEPOSIT_ROLE');
                // for `updateRewards()`
                bytes32 public constant REWARD_UPDATE_ROLE = keccak256('REWARD_UPDATE_ROLE');
                struct UserInfo {
                    uint256 shares; // shares of token staked
                    uint256 userRewardPerTokenPaid; // user reward per token paid
                    uint256 rewards; // pending rewards
                }
                // Precision factor for calculating rewards and exchange rate
                uint256 public constant PRECISION_FACTOR = 10**18;
                IERC20 public immutable x2y2Token;
                IERC20 public immutable rewardToken;
                TokenDistributor public immutable tokenDistributor;
                // Reward rate (block)
                uint256 public currentRewardPerBlock;
                // Last reward adjustment block number
                uint256 public lastRewardAdjustment;
                // Last update block for rewards
                uint256 public lastUpdateBlock;
                // Current end block for the current reward period
                uint256 public periodEndBlock;
                // Reward per token stored
                uint256 public rewardPerTokenStored;
                // Total existing shares
                uint256 public totalShares;
                mapping(address => UserInfo) public userInfo;
                event Deposit(address indexed user, uint256 amount, uint256 harvestedAmount);
                event Harvest(address indexed user, uint256 harvestedAmount);
                event NewRewardPeriod(uint256 numberBlocks, uint256 rewardPerBlock, uint256 reward);
                event Withdraw(address indexed user, uint256 amount, uint256 harvestedAmount);
                /**
                 * @notice Constructor
                 * @param _x2y2Token address of the token staked
                 * @param _rewardToken address of the reward token
                 * @param _tokenDistributor address of the token distributor contract
                 */
                constructor(
                    address _x2y2Token,
                    address _rewardToken,
                    address _tokenDistributor
                ) {
                    rewardToken = IERC20(_rewardToken);
                    x2y2Token = IERC20(_x2y2Token);
                    tokenDistributor = TokenDistributor(_tokenDistributor);
                    _grantRole(DEFAULT_ADMIN_ROLE, msg.sender);
                }
                /**
                 * @notice deposit on behalf of `user`, must be called on fresh deposit only
                 * @param user deposit user
                 * @param amount amount to deposit
                 */
                function depositFor(address user, uint256 amount)
                    external
                    override
                    nonReentrant
                    onlyRole(DEPOSIT_ROLE)
                    returns (bool)
                {
                    require(amount >= PRECISION_FACTOR, 'Deposit: Amount must be >= 1 X2Y2');
                    // Auto compounds for everyone
                    tokenDistributor.harvestAndCompound();
                    // Update reward for user
                    _updateReward(user);
                    // Retrieve total amount staked by this contract
                    (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
                    // transfer stakingToken from **sender**
                    x2y2Token.safeTransferFrom(msg.sender, address(this), amount);
                    uint256 currentShares;
                    // Calculate the number of shares to issue for the user
                    if (totalShares != 0) {
                        currentShares = (amount * totalShares) / totalAmountStaked;
                        // This is a sanity check to prevent deposit for 0 shares
                        require(currentShares != 0, 'Deposit: Fail');
                    } else {
                        currentShares = amount;
                    }
                    // Adjust internal shares
                    userInfo[user].shares += currentShares;
                    totalShares += currentShares;
                    // Verify X2Y2 token allowance and adjust if necessary
                    _checkAndAdjustX2Y2TokenAllowanceIfRequired(amount, address(tokenDistributor));
                    // Deposit user amount in the token distributor contract
                    tokenDistributor.deposit(amount);
                    emit Deposit(user, amount, 0);
                    return true;
                }
                /**
                 * @notice Deposit staked tokens (and collect reward tokens if requested)
                 * @param amount amount to deposit (in X2Y2)
                 * @param claimRewardToken whether to claim reward tokens
                 * @dev There is a limit of 1 X2Y2 per deposit to prevent potential manipulation of current shares
                 */
                function deposit(uint256 amount, bool claimRewardToken) external nonReentrant {
                    require(amount >= PRECISION_FACTOR, 'Deposit: Amount must be >= 1 X2Y2');
                    // Auto compounds for everyone
                    tokenDistributor.harvestAndCompound();
                    // Update reward for user
                    _updateReward(msg.sender);
                    // Retrieve total amount staked by this contract
                    (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
                    // Transfer X2Y2 tokens to this address
                    x2y2Token.safeTransferFrom(msg.sender, address(this), amount);
                    uint256 currentShares;
                    // Calculate the number of shares to issue for the user
                    if (totalShares != 0) {
                        currentShares = (amount * totalShares) / totalAmountStaked;
                        // This is a sanity check to prevent deposit for 0 shares
                        require(currentShares != 0, 'Deposit: Fail');
                    } else {
                        currentShares = amount;
                    }
                    // Adjust internal shares
                    userInfo[msg.sender].shares += currentShares;
                    totalShares += currentShares;
                    uint256 pendingRewards;
                    if (claimRewardToken) {
                        // Fetch pending rewards
                        pendingRewards = userInfo[msg.sender].rewards;
                        if (pendingRewards > 0) {
                            userInfo[msg.sender].rewards = 0;
                            rewardToken.safeTransfer(msg.sender, pendingRewards);
                        }
                    }
                    // Verify X2Y2 token allowance and adjust if necessary
                    _checkAndAdjustX2Y2TokenAllowanceIfRequired(amount, address(tokenDistributor));
                    // Deposit user amount in the token distributor contract
                    tokenDistributor.deposit(amount);
                    emit Deposit(msg.sender, amount, pendingRewards);
                }
                /**
                 * @notice Harvest reward tokens that are pending
                 */
                function harvest() external nonReentrant {
                    // Auto compounds for everyone
                    tokenDistributor.harvestAndCompound();
                    // Update reward for user
                    _updateReward(msg.sender);
                    // Retrieve pending rewards
                    uint256 pendingRewards = userInfo[msg.sender].rewards;
                    // If pending rewards are null, revert
                    require(pendingRewards > 0, 'Harvest: Pending rewards must be > 0');
                    // Adjust user rewards and transfer
                    userInfo[msg.sender].rewards = 0;
                    // Transfer reward token to sender
                    rewardToken.safeTransfer(msg.sender, pendingRewards);
                    emit Harvest(msg.sender, pendingRewards);
                }
                /**
                 * @notice Withdraw staked tokens (and collect reward tokens if requested)
                 * @param shares shares to withdraw
                 * @param claimRewardToken whether to claim reward tokens
                 */
                function withdraw(uint256 shares, bool claimRewardToken) external nonReentrant {
                    require(
                        (shares > 0) && (shares <= userInfo[msg.sender].shares),
                        'Withdraw: Shares equal to 0 or larger than user shares'
                    );
                    _withdraw(shares, claimRewardToken);
                }
                /**
                 * @notice Withdraw all staked tokens (and collect reward tokens if requested)
                 * @param claimRewardToken whether to claim reward tokens
                 */
                function withdrawAll(bool claimRewardToken) external nonReentrant {
                    _withdraw(userInfo[msg.sender].shares, claimRewardToken);
                }
                /**
                 * @notice Update the reward per block (in rewardToken)
                 * @dev Only callable by owner. Owner is meant to be another smart contract.
                 */
                function updateRewards(uint256 reward, uint256 rewardDurationInBlocks)
                    external
                    onlyRole(REWARD_UPDATE_ROLE)
                {
                    // Adjust the current reward per block
                    if (block.number >= periodEndBlock) {
                        currentRewardPerBlock = reward / rewardDurationInBlocks;
                    } else {
                        currentRewardPerBlock =
                            (reward + ((periodEndBlock - block.number) * currentRewardPerBlock)) /
                            rewardDurationInBlocks;
                    }
                    lastUpdateBlock = block.number;
                    periodEndBlock = block.number + rewardDurationInBlocks;
                    emit NewRewardPeriod(rewardDurationInBlocks, currentRewardPerBlock, reward);
                }
                /**
                 * @notice Calculate pending rewards (WETH) for a user
                 * @param user address of the user
                 */
                function calculatePendingRewards(address user) external view returns (uint256) {
                    return _calculatePendingRewards(user);
                }
                /**
                 * @notice Calculate value of X2Y2 for a user given a number of shares owned
                 * @param user address of the user
                 */
                function calculateSharesValueInX2Y2(address user) external view returns (uint256) {
                    // Retrieve amount staked
                    (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
                    // Adjust for pending rewards
                    totalAmountStaked += tokenDistributor.calculatePendingRewards(address(this));
                    // Return user pro-rata of total shares
                    return
                        userInfo[user].shares == 0
                            ? 0
                            : (totalAmountStaked * userInfo[user].shares) / totalShares;
                }
                /**
                 * @notice Calculate price of one share (in X2Y2 token)
                 * Share price is expressed times 1e18
                 */
                function calculateSharePriceInX2Y2() external view returns (uint256) {
                    (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
                    // Adjust for pending rewards
                    totalAmountStaked += tokenDistributor.calculatePendingRewards(address(this));
                    return
                        totalShares == 0
                            ? PRECISION_FACTOR
                            : (totalAmountStaked * PRECISION_FACTOR) / (totalShares);
                }
                /**
                 * @notice Return last block where trading rewards were distributed
                 */
                function lastRewardBlock() external view returns (uint256) {
                    return _lastRewardBlock();
                }
                /**
                 * @notice Calculate pending rewards for a user
                 * @param user address of the user
                 */
                function _calculatePendingRewards(address user) internal view returns (uint256) {
                    return
                        ((userInfo[user].shares *
                            (_rewardPerToken() - (userInfo[user].userRewardPerTokenPaid))) / PRECISION_FACTOR) +
                        userInfo[user].rewards;
                }
                /**
                 * @notice Check current allowance and adjust if necessary
                 * @param _amount amount to transfer
                 * @param _to token to transfer
                 */
                function _checkAndAdjustX2Y2TokenAllowanceIfRequired(uint256 _amount, address _to) internal {
                    if (x2y2Token.allowance(address(this), _to) < _amount) {
                        x2y2Token.approve(_to, type(uint256).max);
                    }
                }
                /**
                 * @notice Return last block where rewards must be distributed
                 */
                function _lastRewardBlock() internal view returns (uint256) {
                    return block.number < periodEndBlock ? block.number : periodEndBlock;
                }
                /**
                 * @notice Return reward per token
                 */
                function _rewardPerToken() internal view returns (uint256) {
                    if (totalShares == 0) {
                        return rewardPerTokenStored;
                    }
                    return
                        rewardPerTokenStored +
                        ((_lastRewardBlock() - lastUpdateBlock) * (currentRewardPerBlock * PRECISION_FACTOR)) /
                        totalShares;
                }
                /**
                 * @notice Update reward for a user account
                 * @param _user address of the user
                 */
                function _updateReward(address _user) internal {
                    if (block.number != lastUpdateBlock) {
                        rewardPerTokenStored = _rewardPerToken();
                        lastUpdateBlock = _lastRewardBlock();
                    }
                    userInfo[_user].rewards = _calculatePendingRewards(_user);
                    userInfo[_user].userRewardPerTokenPaid = rewardPerTokenStored;
                }
                /**
                 * @notice Withdraw staked tokens (and collect reward tokens if requested)
                 * @param shares shares to withdraw
                 * @param claimRewardToken whether to claim reward tokens
                 */
                function _withdraw(uint256 shares, bool claimRewardToken) internal {
                    // Auto compounds for everyone
                    tokenDistributor.harvestAndCompound();
                    // Update reward for user
                    _updateReward(msg.sender);
                    // Retrieve total amount staked and calculated current amount (in X2Y2)
                    (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
                    uint256 currentAmount = (totalAmountStaked * shares) / totalShares;
                    userInfo[msg.sender].shares -= shares;
                    totalShares -= shares;
                    // Withdraw amount equivalent in shares
                    tokenDistributor.withdraw(currentAmount);
                    uint256 pendingRewards;
                    if (claimRewardToken) {
                        // Fetch pending rewards
                        pendingRewards = userInfo[msg.sender].rewards;
                        if (pendingRewards > 0) {
                            userInfo[msg.sender].rewards = 0;
                            rewardToken.safeTransfer(msg.sender, pendingRewards);
                        }
                    }
                    // Transfer X2Y2 tokens to sender
                    x2y2Token.safeTransfer(msg.sender, currentAmount);
                    emit Withdraw(msg.sender, currentAmount, pendingRewards);
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import {ReentrancyGuard} from '@openzeppelin/contracts/security/ReentrancyGuard.sol';
            import {IERC20, SafeERC20} from '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';
            import {IMintableERC20} from './IMintableERC20.sol';
            /**
             * @title TokenDistributor
             * @notice It handles the distribution of X2Y2 token.
             * It auto-adjusts block rewards over a set number of periods.
             */
            contract TokenDistributor is ReentrancyGuard {
                using SafeERC20 for IERC20;
                using SafeERC20 for IMintableERC20;
                struct StakingPeriod {
                    uint256 rewardPerBlockForStaking;
                    uint256 rewardPerBlockForOthers;
                    uint256 periodLengthInBlock;
                }
                struct UserInfo {
                    uint256 amount; // Amount of staked tokens provided by user
                    uint256 rewardDebt; // Reward debt
                }
                // Precision factor for calculating rewards
                uint256 public constant PRECISION_FACTOR = 10**12;
                IMintableERC20 public immutable x2y2Token;
                address public immutable tokenSplitter;
                // Number of reward periods
                uint256 public immutable NUMBER_PERIODS;
                // Block number when rewards start
                uint256 public immutable START_BLOCK;
                // Accumulated tokens per share
                uint256 public accTokenPerShare;
                // Current phase for rewards
                uint256 public currentPhase;
                // Block number when rewards end
                uint256 public endBlock;
                // Block number of the last update
                uint256 public lastRewardBlock;
                // Tokens distributed per block for other purposes (team + treasury + trading rewards)
                uint256 public rewardPerBlockForOthers;
                // Tokens distributed per block for staking
                uint256 public rewardPerBlockForStaking;
                // Total amount staked
                uint256 public totalAmountStaked;
                mapping(uint256 => StakingPeriod) public stakingPeriod;
                mapping(address => UserInfo) public userInfo;
                event Compound(address indexed user, uint256 harvestedAmount);
                event Deposit(address indexed user, uint256 amount, uint256 harvestedAmount);
                event NewRewardsPerBlock(
                    uint256 indexed currentPhase,
                    uint256 startBlock,
                    uint256 rewardPerBlockForStaking,
                    uint256 rewardPerBlockForOthers
                );
                event Withdraw(address indexed user, uint256 amount, uint256 harvestedAmount);
                /**
                 * @notice Constructor
                 * @param _x2y2Token token address
                 * @param _tokenSplitter token splitter contract address (for team and trading rewards)
                 * @param _startBlock start block for reward program
                 * @param _rewardsPerBlockForStaking array of rewards per block for staking
                 * @param _rewardsPerBlockForOthers array of rewards per block for other purposes (team + treasury + trading rewards)
                 * @param _periodLengthesInBlocks array of period lengthes
                 * @param _numberPeriods number of periods with different rewards/lengthes (e.g., if 3 changes --> 4 periods)
                 */
                constructor(
                    address _x2y2Token,
                    address _tokenSplitter,
                    uint256 _startBlock,
                    uint256[] memory _rewardsPerBlockForStaking,
                    uint256[] memory _rewardsPerBlockForOthers,
                    uint256[] memory _periodLengthesInBlocks,
                    uint256 _numberPeriods
                ) {
                    require(
                        (_periodLengthesInBlocks.length == _numberPeriods) &&
                            (_rewardsPerBlockForStaking.length == _numberPeriods) &&
                            (_rewardsPerBlockForStaking.length == _numberPeriods),
                        'Distributor: Lengthes must match numberPeriods'
                    );
                    // 1. Operational checks for supply
                    uint256 nonCirculatingSupply = IMintableERC20(_x2y2Token).SUPPLY_CAP() -
                        IMintableERC20(_x2y2Token).totalSupply();
                    uint256 amountTokensToBeMinted;
                    for (uint256 i = 0; i < _numberPeriods; i++) {
                        amountTokensToBeMinted +=
                            (_rewardsPerBlockForStaking[i] * _periodLengthesInBlocks[i]) +
                            (_rewardsPerBlockForOthers[i] * _periodLengthesInBlocks[i]);
                        stakingPeriod[i] = StakingPeriod({
                            rewardPerBlockForStaking: _rewardsPerBlockForStaking[i],
                            rewardPerBlockForOthers: _rewardsPerBlockForOthers[i],
                            periodLengthInBlock: _periodLengthesInBlocks[i]
                        });
                    }
                    require(
                        amountTokensToBeMinted == nonCirculatingSupply,
                        'Distributor: Wrong reward parameters'
                    );
                    // 2. Store values
                    x2y2Token = IMintableERC20(_x2y2Token);
                    tokenSplitter = _tokenSplitter;
                    rewardPerBlockForStaking = _rewardsPerBlockForStaking[0];
                    rewardPerBlockForOthers = _rewardsPerBlockForOthers[0];
                    START_BLOCK = _startBlock;
                    endBlock = _startBlock + _periodLengthesInBlocks[0];
                    NUMBER_PERIODS = _numberPeriods;
                    // Set the lastRewardBlock as the startBlock
                    lastRewardBlock = _startBlock;
                }
                /**
                 * @notice Deposit staked tokens and compounds pending rewards
                 * @param amount amount to deposit (in X2Y2)
                 */
                function deposit(uint256 amount) external nonReentrant {
                    require(amount > 0, 'Deposit: Amount must be > 0');
                    require(block.number >= START_BLOCK, 'Deposit: Not started yet');
                    // Update pool information
                    _updatePool();
                    // Transfer X2Y2 tokens to this contract
                    x2y2Token.safeTransferFrom(msg.sender, address(this), amount);
                    uint256 pendingRewards;
                    // If not new deposit, calculate pending rewards (for auto-compounding)
                    if (userInfo[msg.sender].amount > 0) {
                        pendingRewards =
                            ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
                            userInfo[msg.sender].rewardDebt;
                    }
                    // Adjust user information
                    userInfo[msg.sender].amount += (amount + pendingRewards);
                    userInfo[msg.sender].rewardDebt =
                        (userInfo[msg.sender].amount * accTokenPerShare) /
                        PRECISION_FACTOR;
                    // Increase totalAmountStaked
                    totalAmountStaked += (amount + pendingRewards);
                    emit Deposit(msg.sender, amount, pendingRewards);
                }
                /**
                 * @notice Compound based on pending rewards
                 */
                function harvestAndCompound() external nonReentrant {
                    // Update pool information
                    _updatePool();
                    // Calculate pending rewards
                    uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) /
                        PRECISION_FACTOR) - userInfo[msg.sender].rewardDebt;
                    // Return if no pending rewards
                    if (pendingRewards == 0) {
                        // It doesn't throw revertion (to help with the fee-sharing auto-compounding contract)
                        return;
                    }
                    // Adjust user amount for pending rewards
                    userInfo[msg.sender].amount += pendingRewards;
                    // Adjust totalAmountStaked
                    totalAmountStaked += pendingRewards;
                    // Recalculate reward debt based on new user amount
                    userInfo[msg.sender].rewardDebt =
                        (userInfo[msg.sender].amount * accTokenPerShare) /
                        PRECISION_FACTOR;
                    emit Compound(msg.sender, pendingRewards);
                }
                /**
                 * @notice Update pool rewards
                 */
                function updatePool() external nonReentrant {
                    _updatePool();
                }
                /**
                 * @notice Withdraw staked tokens and compound pending rewards
                 * @param amount amount to withdraw
                 */
                function withdraw(uint256 amount) external nonReentrant {
                    require(
                        (userInfo[msg.sender].amount >= amount) && (amount > 0),
                        'Withdraw: Amount must be > 0 or lower than user balance'
                    );
                    // Update pool
                    _updatePool();
                    // Calculate pending rewards
                    uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) /
                        PRECISION_FACTOR) - userInfo[msg.sender].rewardDebt;
                    // Adjust user information
                    userInfo[msg.sender].amount = userInfo[msg.sender].amount + pendingRewards - amount;
                    userInfo[msg.sender].rewardDebt =
                        (userInfo[msg.sender].amount * accTokenPerShare) /
                        PRECISION_FACTOR;
                    // Adjust total amount staked
                    totalAmountStaked = totalAmountStaked + pendingRewards - amount;
                    // Transfer X2Y2 tokens to the sender
                    x2y2Token.safeTransfer(msg.sender, amount);
                    emit Withdraw(msg.sender, amount, pendingRewards);
                }
                /**
                 * @notice Withdraw all staked tokens and collect tokens
                 */
                function withdrawAll() external nonReentrant {
                    require(userInfo[msg.sender].amount > 0, 'Withdraw: Amount must be > 0');
                    // Update pool
                    _updatePool();
                    // Calculate pending rewards and amount to transfer (to the sender)
                    uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) /
                        PRECISION_FACTOR) - userInfo[msg.sender].rewardDebt;
                    uint256 amountToTransfer = userInfo[msg.sender].amount + pendingRewards;
                    // Adjust total amount staked
                    totalAmountStaked = totalAmountStaked - userInfo[msg.sender].amount;
                    // Adjust user information
                    userInfo[msg.sender].amount = 0;
                    userInfo[msg.sender].rewardDebt = 0;
                    // Transfer X2Y2 tokens to the sender
                    x2y2Token.safeTransfer(msg.sender, amountToTransfer);
                    emit Withdraw(msg.sender, amountToTransfer, pendingRewards);
                }
                /**
                 * @notice Calculate pending rewards for a user
                 * @param user address of the user
                 * @return Pending rewards
                 */
                function calculatePendingRewards(address user) external view returns (uint256) {
                    if ((block.number > lastRewardBlock) && (totalAmountStaked != 0)) {
                        uint256 multiplier = _getMultiplier(lastRewardBlock, block.number);
                        uint256 tokenRewardForStaking = multiplier * rewardPerBlockForStaking;
                        uint256 adjustedEndBlock = endBlock;
                        uint256 adjustedCurrentPhase = currentPhase;
                        // Check whether to adjust multipliers and reward per block
                        while (
                            (block.number > adjustedEndBlock) && (adjustedCurrentPhase < (NUMBER_PERIODS - 1))
                        ) {
                            // Update current phase
                            adjustedCurrentPhase++;
                            // Update rewards per block
                            uint256 adjustedRewardPerBlockForStaking = stakingPeriod[adjustedCurrentPhase]
                                .rewardPerBlockForStaking;
                            // Calculate adjusted block number
                            uint256 previousEndBlock = adjustedEndBlock;
                            // Update end block
                            adjustedEndBlock =
                                previousEndBlock +
                                stakingPeriod[adjustedCurrentPhase].periodLengthInBlock;
                            // Calculate new multiplier
                            uint256 newMultiplier = (block.number <= adjustedEndBlock)
                                ? (block.number - previousEndBlock)
                                : stakingPeriod[adjustedCurrentPhase].periodLengthInBlock;
                            // Adjust token rewards for staking
                            tokenRewardForStaking += (newMultiplier * adjustedRewardPerBlockForStaking);
                        }
                        uint256 adjustedTokenPerShare = accTokenPerShare +
                            (tokenRewardForStaking * PRECISION_FACTOR) /
                            totalAmountStaked;
                        return
                            (userInfo[user].amount * adjustedTokenPerShare) /
                            PRECISION_FACTOR -
                            userInfo[user].rewardDebt;
                    } else {
                        return
                            (userInfo[user].amount * accTokenPerShare) /
                            PRECISION_FACTOR -
                            userInfo[user].rewardDebt;
                    }
                }
                /**
                 * @notice Update reward variables of the pool
                 */
                function _updatePool() internal {
                    if (block.number <= lastRewardBlock) {
                        return;
                    }
                    if (totalAmountStaked == 0) {
                        lastRewardBlock = block.number;
                        return;
                    }
                    // Calculate multiplier
                    uint256 multiplier = _getMultiplier(lastRewardBlock, block.number);
                    // Calculate rewards for staking and others
                    uint256 tokenRewardForStaking = multiplier * rewardPerBlockForStaking;
                    uint256 tokenRewardForOthers = multiplier * rewardPerBlockForOthers;
                    // Check whether to adjust multipliers and reward per block
                    while ((block.number > endBlock) && (currentPhase < (NUMBER_PERIODS - 1))) {
                        // Update rewards per block
                        _updateRewardsPerBlock(endBlock);
                        uint256 previousEndBlock = endBlock;
                        // Adjust the end block
                        endBlock += stakingPeriod[currentPhase].periodLengthInBlock;
                        // Adjust multiplier to cover the missing periods with other lower inflation schedule
                        uint256 newMultiplier = _getMultiplier(previousEndBlock, block.number);
                        // Adjust token rewards
                        tokenRewardForStaking += (newMultiplier * rewardPerBlockForStaking);
                        tokenRewardForOthers += (newMultiplier * rewardPerBlockForOthers);
                    }
                    // Mint tokens only if token rewards for staking are not null
                    if (tokenRewardForStaking > 0) {
                        // It allows protection against potential issues to prevent funds from being locked
                        bool mintStatus = x2y2Token.mint(address(this), tokenRewardForStaking);
                        if (mintStatus) {
                            accTokenPerShare =
                                accTokenPerShare +
                                ((tokenRewardForStaking * PRECISION_FACTOR) / totalAmountStaked);
                        }
                        x2y2Token.mint(tokenSplitter, tokenRewardForOthers);
                    }
                    // Update last reward block only if it wasn't updated after or at the end block
                    if (lastRewardBlock <= endBlock) {
                        lastRewardBlock = block.number;
                    }
                }
                /**
                 * @notice Update rewards per block
                 * @dev Rewards are halved by 2 (for staking + others)
                 */
                function _updateRewardsPerBlock(uint256 _newStartBlock) internal {
                    // Update current phase
                    currentPhase++;
                    // Update rewards per block
                    rewardPerBlockForStaking = stakingPeriod[currentPhase].rewardPerBlockForStaking;
                    rewardPerBlockForOthers = stakingPeriod[currentPhase].rewardPerBlockForOthers;
                    emit NewRewardsPerBlock(
                        currentPhase,
                        _newStartBlock,
                        rewardPerBlockForStaking,
                        rewardPerBlockForOthers
                    );
                }
                /**
                 * @notice Return reward multiplier over the given "from" to "to" block.
                 * @param from block to start calculating reward
                 * @param to block to finish calculating reward
                 * @return the multiplier for the period
                 */
                function _getMultiplier(uint256 from, uint256 to) internal view returns (uint256) {
                    if (to <= endBlock) {
                        return to - from;
                    } else if (from >= endBlock) {
                        return 0;
                    } else {
                        return endBlock - from;
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            interface IRewardConvertor {
                function convert(
                    address tokenToSell,
                    address tokenToBuy,
                    uint256 amount,
                    bytes calldata additionalData
                ) external returns (uint256);
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
            interface IMintableERC20 is IERC20 {
                function SUPPLY_CAP() external view returns (uint256);
                function mint(address account, uint256 amount) external returns (bool);
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.8.0;
            interface ITokenStaked {
                function getTotalStaked() external view returns (uint256);
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev External interface of AccessControl declared to support ERC165 detection.
             */
            interface IAccessControl {
                /**
                 * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
                 *
                 * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
                 * {RoleAdminChanged} not being emitted signaling this.
                 *
                 * _Available since v3.1._
                 */
                event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
                /**
                 * @dev Emitted when `account` is granted `role`.
                 *
                 * `sender` is the account that originated the contract call, an admin role
                 * bearer except when using {AccessControl-_setupRole}.
                 */
                event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
                /**
                 * @dev Emitted when `account` is revoked `role`.
                 *
                 * `sender` is the account that originated the contract call:
                 *   - if using `revokeRole`, it is the admin role bearer
                 *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
                 */
                event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
                /**
                 * @dev Returns `true` if `account` has been granted `role`.
                 */
                function hasRole(bytes32 role, address account) external view returns (bool);
                /**
                 * @dev Returns the admin role that controls `role`. See {grantRole} and
                 * {revokeRole}.
                 *
                 * To change a role's admin, use {AccessControl-_setRoleAdmin}.
                 */
                function getRoleAdmin(bytes32 role) external view returns (bytes32);
                /**
                 * @dev Grants `role` to `account`.
                 *
                 * If `account` had not been already granted `role`, emits a {RoleGranted}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function grantRole(bytes32 role, address account) external;
                /**
                 * @dev Revokes `role` from `account`.
                 *
                 * If `account` had been granted `role`, emits a {RoleRevoked} event.
                 *
                 * Requirements:
                 *
                 * - the caller must have ``role``'s admin role.
                 */
                function revokeRole(bytes32 role, address account) external;
                /**
                 * @dev Revokes `role` from the calling account.
                 *
                 * Roles are often managed via {grantRole} and {revokeRole}: this function's
                 * purpose is to provide a mechanism for accounts to lose their privileges
                 * if they are compromised (such as when a trusted device is misplaced).
                 *
                 * If the calling account had been granted `role`, emits a {RoleRevoked}
                 * event.
                 *
                 * Requirements:
                 *
                 * - the caller must be `account`.
                 */
                function renounceRole(bytes32 role, address account) external;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev String operations.
             */
            library Strings {
                bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                /**
                 * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                 */
                function toString(uint256 value) internal pure returns (string memory) {
                    // Inspired by OraclizeAPI's implementation - MIT licence
                    // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                    if (value == 0) {
                        return "0";
                    }
                    uint256 temp = value;
                    uint256 digits;
                    while (temp != 0) {
                        digits++;
                        temp /= 10;
                    }
                    bytes memory buffer = new bytes(digits);
                    while (value != 0) {
                        digits -= 1;
                        buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                        value /= 10;
                    }
                    return string(buffer);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                 */
                function toHexString(uint256 value) internal pure returns (string memory) {
                    if (value == 0) {
                        return "0x00";
                    }
                    uint256 temp = value;
                    uint256 length = 0;
                    while (temp != 0) {
                        length++;
                        temp >>= 8;
                    }
                    return toHexString(value, length);
                }
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                 */
                function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                    bytes memory buffer = new bytes(2 * length + 2);
                    buffer[0] = "0";
                    buffer[1] = "x";
                    for (uint256 i = 2 * length + 1; i > 1; --i) {
                        buffer[i] = _HEX_SYMBOLS[value & 0xf];
                        value >>= 4;
                    }
                    require(value == 0, "Strings: hex length insufficient");
                    return string(buffer);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
            pragma solidity ^0.8.0;
            import "./IERC165.sol";
            /**
             * @dev Implementation of the {IERC165} interface.
             *
             * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
             * for the additional interface id that will be supported. For example:
             *
             * ```solidity
             * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
             *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
             * }
             * ```
             *
             * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
             */
            abstract contract ERC165 is IERC165 {
                /**
                 * @dev See {IERC165-supportsInterface}.
                 */
                function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                    return interfaceId == type(IERC165).interfaceId;
                }
            }
            // 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 ^0.8.0;
            interface IStakeFor {
                function depositFor(address user, uint256 amount) external returns (bool);
            }
            

            File 8 of 8: DelegatedPaymentSplitter
            // SPDX-License-Identifier: MIT
            // Copyright (c) 2022 the ethier authors (github.com/divergencetech/ethier)
            pragma solidity >=0.8.0 <0.9.0;
            import "@openzeppelin/contracts-upgradeable/finance/PaymentSplitterUpgradeable.sol";
            /**
            @notice This contract functions identically to a standard OpenZeppelin
            PaymentSplitter except that it can be cheaply cloned and deployed via the
            PaymentSplitterFactory. The upgradeable functionality is not used, but is
            required for cloning with an EIP-1677 minimal contract proxy.
            @dev Cloning only replicates the implementation logic, but not the data
            associated with each clone. See EIP-1677 for details.
            NOTE: there is likely no need to import this contract directly; instead see the
            ethier documentation for the deployed factory addresses.
             */
            contract DelegatedPaymentSplitter is PaymentSplitterUpgradeable {
                /**
                @dev Initializes the PaymentSplitter, akin to a constructor. MUST be called
                by the Factory, in the same transaction as deployment, as there are no
                protections in place.
                 */
                function initialize(address[] memory payees, uint256[] memory shares)
                    external
                    payable
                    initializer
                {
                    __PaymentSplitter_init(payees, shares);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (finance/PaymentSplitter.sol)
            pragma solidity ^0.8.0;
            import "../token/ERC20/utils/SafeERC20Upgradeable.sol";
            import "../utils/AddressUpgradeable.sol";
            import "../utils/ContextUpgradeable.sol";
            import "../proxy/utils/Initializable.sol";
            /**
             * @title PaymentSplitter
             * @dev This contract allows to split Ether payments among a group of accounts. The sender does not need to be aware
             * that the Ether will be split in this way, since it is handled transparently by the contract.
             *
             * The split can be in equal parts or in any other arbitrary proportion. The way this is specified is by assigning each
             * account to a number of shares. Of all the Ether that this contract receives, each account will then be able to claim
             * an amount proportional to the percentage of total shares they were assigned.
             *
             * `PaymentSplitter` follows a _pull payment_ model. This means that payments are not automatically forwarded to the
             * accounts but kept in this contract, and the actual transfer is triggered as a separate step by calling the {release}
             * function.
             *
             * NOTE: This contract assumes that ERC20 tokens will behave similarly to native tokens (Ether). Rebasing tokens, and
             * tokens that apply fees during transfers, are likely to not be supported as expected. If in doubt, we encourage you
             * to run tests before sending real value to this contract.
             */
            contract PaymentSplitterUpgradeable is Initializable, ContextUpgradeable {
                event PayeeAdded(address account, uint256 shares);
                event PaymentReleased(address to, uint256 amount);
                event ERC20PaymentReleased(IERC20Upgradeable indexed token, address to, uint256 amount);
                event PaymentReceived(address from, uint256 amount);
                uint256 private _totalShares;
                uint256 private _totalReleased;
                mapping(address => uint256) private _shares;
                mapping(address => uint256) private _released;
                address[] private _payees;
                mapping(IERC20Upgradeable => uint256) private _erc20TotalReleased;
                mapping(IERC20Upgradeable => mapping(address => uint256)) private _erc20Released;
                /**
                 * @dev Creates an instance of `PaymentSplitter` where each account in `payees` is assigned the number of shares at
                 * the matching position in the `shares` array.
                 *
                 * All addresses in `payees` must be non-zero. Both arrays must have the same non-zero length, and there must be no
                 * duplicates in `payees`.
                 */
                function __PaymentSplitter_init(address[] memory payees, uint256[] memory shares_) internal onlyInitializing {
                    __Context_init_unchained();
                    __PaymentSplitter_init_unchained(payees, shares_);
                }
                function __PaymentSplitter_init_unchained(address[] memory payees, uint256[] memory shares_) internal onlyInitializing {
                    require(payees.length == shares_.length, "PaymentSplitter: payees and shares length mismatch");
                    require(payees.length > 0, "PaymentSplitter: no payees");
                    for (uint256 i = 0; i < payees.length; i++) {
                        _addPayee(payees[i], shares_[i]);
                    }
                }
                /**
                 * @dev The Ether received will be logged with {PaymentReceived} events. Note that these events are not fully
                 * reliable: it's possible for a contract to receive Ether without triggering this function. This only affects the
                 * reliability of the events, and not the actual splitting of Ether.
                 *
                 * To learn more about this see the Solidity documentation for
                 * https://solidity.readthedocs.io/en/latest/contracts.html#fallback-function[fallback
                 * functions].
                 */
                receive() external payable virtual {
                    emit PaymentReceived(_msgSender(), msg.value);
                }
                /**
                 * @dev Getter for the total shares held by payees.
                 */
                function totalShares() public view returns (uint256) {
                    return _totalShares;
                }
                /**
                 * @dev Getter for the total amount of Ether already released.
                 */
                function totalReleased() public view returns (uint256) {
                    return _totalReleased;
                }
                /**
                 * @dev Getter for the total amount of `token` already released. `token` should be the address of an IERC20
                 * contract.
                 */
                function totalReleased(IERC20Upgradeable token) public view returns (uint256) {
                    return _erc20TotalReleased[token];
                }
                /**
                 * @dev Getter for the amount of shares held by an account.
                 */
                function shares(address account) public view returns (uint256) {
                    return _shares[account];
                }
                /**
                 * @dev Getter for the amount of Ether already released to a payee.
                 */
                function released(address account) public view returns (uint256) {
                    return _released[account];
                }
                /**
                 * @dev Getter for the amount of `token` tokens already released to a payee. `token` should be the address of an
                 * IERC20 contract.
                 */
                function released(IERC20Upgradeable token, address account) public view returns (uint256) {
                    return _erc20Released[token][account];
                }
                /**
                 * @dev Getter for the address of the payee number `index`.
                 */
                function payee(uint256 index) public view returns (address) {
                    return _payees[index];
                }
                /**
                 * @dev Triggers a transfer to `account` of the amount of Ether they are owed, according to their percentage of the
                 * total shares and their previous withdrawals.
                 */
                function release(address payable account) public virtual {
                    require(_shares[account] > 0, "PaymentSplitter: account has no shares");
                    uint256 totalReceived = address(this).balance + totalReleased();
                    uint256 payment = _pendingPayment(account, totalReceived, released(account));
                    require(payment != 0, "PaymentSplitter: account is not due payment");
                    _released[account] += payment;
                    _totalReleased += payment;
                    AddressUpgradeable.sendValue(account, payment);
                    emit PaymentReleased(account, payment);
                }
                /**
                 * @dev Triggers a transfer to `account` of the amount of `token` tokens they are owed, according to their
                 * percentage of the total shares and their previous withdrawals. `token` must be the address of an IERC20
                 * contract.
                 */
                function release(IERC20Upgradeable token, address account) public virtual {
                    require(_shares[account] > 0, "PaymentSplitter: account has no shares");
                    uint256 totalReceived = token.balanceOf(address(this)) + totalReleased(token);
                    uint256 payment = _pendingPayment(account, totalReceived, released(token, account));
                    require(payment != 0, "PaymentSplitter: account is not due payment");
                    _erc20Released[token][account] += payment;
                    _erc20TotalReleased[token] += payment;
                    SafeERC20Upgradeable.safeTransfer(token, account, payment);
                    emit ERC20PaymentReleased(token, account, payment);
                }
                /**
                 * @dev internal logic for computing the pending payment of an `account` given the token historical balances and
                 * already released amounts.
                 */
                function _pendingPayment(
                    address account,
                    uint256 totalReceived,
                    uint256 alreadyReleased
                ) private view returns (uint256) {
                    return (totalReceived * _shares[account]) / _totalShares - alreadyReleased;
                }
                /**
                 * @dev Add a new payee to the contract.
                 * @param account The address of the payee to add.
                 * @param shares_ The number of shares owned by the payee.
                 */
                function _addPayee(address account, uint256 shares_) private {
                    require(account != address(0), "PaymentSplitter: account is the zero address");
                    require(shares_ > 0, "PaymentSplitter: shares are 0");
                    require(_shares[account] == 0, "PaymentSplitter: account already has shares");
                    _payees.push(account);
                    _shares[account] = shares_;
                    _totalShares = _totalShares + shares_;
                    emit PayeeAdded(account, shares_);
                }
                uint256[43] private __gap;
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (proxy/utils/Initializable.sol)
            pragma solidity ^0.8.0;
            import "../../utils/AddressUpgradeable.sol";
            /**
             * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
             * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
             * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
             * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
             *
             * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
             * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
             *
             * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
             * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
             *
             * [CAUTION]
             * ====
             * Avoid leaving a contract uninitialized.
             *
             * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
             * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
             * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
             *
             * [.hljs-theme-light.nopadding]
             * ```
             * /// @custom:oz-upgrades-unsafe-allow constructor
             * constructor() initializer {}
             * ```
             * ====
             */
            abstract contract Initializable {
                /**
                 * @dev Indicates that the contract has been initialized.
                 */
                bool private _initialized;
                /**
                 * @dev Indicates that the contract is in the process of being initialized.
                 */
                bool private _initializing;
                /**
                 * @dev Modifier to protect an initializer function from being invoked twice.
                 */
                modifier initializer() {
                    // If the contract is initializing we ignore whether _initialized is set in order to support multiple
                    // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
                    // contract may have been reentered.
                    require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");
                    bool isTopLevelCall = !_initializing;
                    if (isTopLevelCall) {
                        _initializing = true;
                        _initialized = true;
                    }
                    _;
                    if (isTopLevelCall) {
                        _initializing = false;
                    }
                }
                /**
                 * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                 * {initializer} modifier, directly or indirectly.
                 */
                modifier onlyInitializing() {
                    require(_initializing, "Initializable: contract is not initializing");
                    _;
                }
                function _isConstructor() private view returns (bool) {
                    return !AddressUpgradeable.isContract(address(this));
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
            pragma solidity ^0.8.0;
            import "../proxy/utils/Initializable.sol";
            /**
             * @dev Provides information about the current execution context, including the
             * sender of the transaction and its data. While these are generally available
             * via msg.sender and msg.data, they should not be accessed in such a direct
             * manner, since when dealing with meta-transactions the account sending and
             * paying for execution may not be the actual sender (as far as an application
             * is concerned).
             *
             * This contract is only required for intermediate, library-like contracts.
             */
            abstract contract ContextUpgradeable is Initializable {
                function __Context_init() internal onlyInitializing {
                    __Context_init_unchained();
                }
                function __Context_init_unchained() internal onlyInitializing {
                }
                function _msgSender() internal view virtual returns (address) {
                    return msg.sender;
                }
                function _msgData() internal view virtual returns (bytes calldata) {
                    return msg.data;
                }
                uint256[50] private __gap;
            }
            // 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 AddressUpgradeable {
                /**
                 * @dev Returns true if `account` is a contract.
                 *
                 * [IMPORTANT]
                 * ====
                 * It is unsafe to assume that an address for which this function returns
                 * false is an externally-owned account (EOA) and not a contract.
                 *
                 * Among others, `isContract` will return false for the following
                 * types of addresses:
                 *
                 *  - an externally-owned account
                 *  - a contract in construction
                 *  - an address where a contract will be created
                 *  - an address where a contract lived, but was destroyed
                 * ====
                 */
                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 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 (token/ERC20/utils/SafeERC20.sol)
            pragma solidity ^0.8.0;
            import "../IERC20Upgradeable.sol";
            import "../../../utils/AddressUpgradeable.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 SafeERC20Upgradeable {
                using AddressUpgradeable for address;
                function safeTransfer(
                    IERC20Upgradeable token,
                    address to,
                    uint256 value
                ) internal {
                    _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                }
                function safeTransferFrom(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(
                    IERC20Upgradeable 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(IERC20Upgradeable 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 v4.4.1 (token/ERC20/IERC20.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev Interface of the ERC20 standard as defined in the EIP.
             */
            interface IERC20Upgradeable {
                /**
                 * @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);
            }