ETH Price: $1,911.31 (-3.49%)

Transaction Decoder

Block:
23798595 at Nov-14-2025 04:22:35 PM +UTC
Transaction Fee:
0.000759622232124416 ETH $1.45
Gas Used:
275,456 Gas / 2.757689911 Gwei

Emitted Events:

383 ERC1967Proxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x0000000000000000000000000000000000000000000000000000000000000000, 0x000000000000000000000000146448fb756ed766fe4f87f7a0a1d636d6de8d92, 000000000000000000000000000000000000000000000000022da584ddc69533 )
384 0x29469395eaf6f95920e59f858042f0e28d98a20b.0x06a333c2d6fe967ca967f7a35be2eb45e8caeb6cf05e16f55d42b91b5fe31255( 0x06a333c2d6fe967ca967f7a35be2eb45e8caeb6cf05e16f55d42b91b5fe31255, 4c00e49041c805c2033b459726406e810ae61b7d8a5f7cea5d00c9fdd245012a, 00000000000000000000000000000000000000000000000000000000000683a5, 000000000000000000000000524cab2ec69124574082676e6f654a18df49a048, 000000000000000000000000e9bab3816a139827fe218d58699097b359680380, 000000000000000000000000146448fb756ed766fe4f87f7a0a1d636d6de8d92, 00000000000000000000000000000000000000000000000006f05b59d3b20000, 00000000000000000000000000000000000000000000000000000000000009ba, 0000000000000000000000000000000000000000000000000000000000000f07, 0000000000000000000000000000000000000000000000000000000000002328 )
385 ERC1967Proxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x000000000000000000000000e9bab3816a139827fe218d58699097b359680380, 0x0000000000000000000000000000000000000000000000000000000000000000, 00000000000000000000000000000000000000000000000006f05b59d3b20000 )
386 ERC1967Proxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x000000000000000000000000146448fb756ed766fe4f87f7a0a1d636d6de8d92, 0x0000000000000000000000000000000000000000000000000000000000000000, 000000000000000000000000000000000000000000000000022dc6aad221b600 )
387 LilPudgys.Approval( owner=0x0d8d4708374f669b5b347098d740d1d9dfb91df3, approved=0x00000000...000000000, tokenId=3847 )
388 LilPudgys.Transfer( from=0x0d8d4708374f669b5b347098d740d1d9dfb91df3, to=[Receiver] 0x29469395eaf6f95920e59f858042f0e28d98a20b, tokenId=3847 )
389 0xb2ecfe4e4d61f8790bbb9de2d1259b9e2410cea5.0x1d5e12b51dee5e4d34434576c3fb99714a85f57b0fd546ada4b0bddd736d12b2( 0x1d5e12b51dee5e4d34434576c3fb99714a85f57b0fd546ada4b0bddd736d12b2, 5e58cb75a8b43d11674ad8a6d85720adc1cedd1504189d2691c5cea039c331a1, 0000000000000000000f07000d8d4708374f669b5b347098d740d1d9dfb91df3, 00000000091e2204a5d3b600524cab2ec69124574082676e6f654a18df49a048 )

Account State Difference:

  Address   Before After State Difference Code
0x00000000...d351887Ac 9,487.101062883814694683 Eth9,486.601026436917575246 Eth0.500036446897119437
0x0d8D4708...9dFB91DF3 0.029115559293538586 Eth0.686115558293538586 Eth0.656999999
0x146448Fb...6D6de8D92
0.262099437322133861 Eth
Nonce: 6201
0.104376262987128882 Eth
Nonce: 6202
0.157723174335004979
0x29469395...28D98a20B
(Blur: Blend)
(quasarbuilder)
12.511421880479062192 Eth12.511972792479062192 Eth0.000550912
0x524cAB2e...8df49A048
0xb2ecfE4E...e2410CEA5
(Blur.io: Marketplace 3)

Execution Trace

ETH 0.156963552102880563 Blur: Blend.be5898ff( )
  • ETH 0.156963552102880563 Blend.buyToBorrowV2ETH( ) => ( lienId=426917 )
    • ETH 0.156963552102880563 ERC1967Proxy.f340fa01( )
      • ETH 0.156963552102880563 BlurPool.deposit( user=0x146448Fb756Ed766FE4F87F7A0A1d636D6de8D92 )
      • Null: 0x000...001.b56807cb( )
      • Null: 0x000...001.923f16ae( )
      • ETH 0.156963552102880563 Helpers.7a8d3ec5( )
        • ERC1967Proxy.9555a942( )
          • BlurPool.withdrawFrom( from=0xe9bAB3816a139827fE218D58699097B359680380, to=0x29469395eAf6f95920E59F858042f0e28D98a20B, amount=500000000000000000 )
            • ETH 0.5 Blur: Blend.CALL( )
              • ETH 0.5 Blend.DELEGATECALL( )
              • ERC1967Proxy.9555a942( )
                • BlurPool.withdrawFrom( from=0x146448Fb756Ed766FE4F87F7A0A1d636D6de8D92, to=0x29469395eAf6f95920E59F858042f0e28D98a20B, amount=156999999000000000 )
                  • ETH 0.156999999 Blur: Blend.CALL( )
                    • ETH 0.156999999 Blend.DELEGATECALL( )
                    • ETH 0.656999999 Blur.io: Marketplace 3.70bce2d6( )
                      • ETH 0.656999999 0x5fa60726e62c50af45ff2f6280c468da438a7837.70bce2d6( )
                        • Null: 0x000...001.f9beb409( )
                        • Null: 0x000...001.5d5ce49b( )
                        • Delegate.transfer( taker=0x29469395eAf6f95920E59F858042f0e28D98a20B, orderType=0, transfers=, length=1 ) => ( successful=[true] )
                          • LilPudgys.safeTransferFrom( from=0x0d8D4708374F669B5B347098D740d1d9dFB91DF3, to=0x29469395eAf6f95920E59F858042f0e28D98a20B, tokenId=3847 )
                          • ETH 0.656999999 0x0d8d4708374f669b5b347098d740d1d9dfb91df3.CALL( )
                            File 1 of 6: ERC1967Proxy
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (proxy/ERC1967/ERC1967Proxy.sol)
                            pragma solidity 0.8.17;
                            // OpenZeppelin Contracts v4.4.1 (proxy/Proxy.sol)
                            /**
                             * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
                             * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
                             * be specified by overriding the virtual {_implementation} function.
                             *
                             * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
                             * different contract through the {_delegate} function.
                             *
                             * The success and return data of the delegated call will be returned back to the caller of the proxy.
                             */
                            abstract contract Proxy {
                                /**
                                 * @dev Delegates the current call to `implementation`.
                                 *
                                 * This function does not return to its internall call site, it will return directly to the external caller.
                                 */
                                function _delegate(address implementation) internal virtual {
                                    assembly {
                                        // Copy msg.data. We take full control of memory in this inline assembly
                                        // block because it will not return to Solidity code. We overwrite the
                                        // Solidity scratch pad at memory position 0.
                                        calldatacopy(0, 0, calldatasize())
                                        // Call the implementation.
                                        // out and outsize are 0 because we don't know the size yet.
                                        let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                                        // Copy the returned data.
                                        returndatacopy(0, 0, returndatasize())
                                        switch result
                                        // delegatecall returns 0 on error.
                                        case 0 {
                                            revert(0, returndatasize())
                                        }
                                        default {
                                            return(0, returndatasize())
                                        }
                                    }
                                }
                                /**
                                 * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                                 * and {_fallback} should delegate.
                                 */
                                function _implementation() internal view virtual returns (address);
                                /**
                                 * @dev Delegates the current call to the address returned by `_implementation()`.
                                 *
                                 * This function does not return to its 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 {}
                            }
                            // OpenZeppelin Contracts v4.4.1 (proxy/ERC1967/ERC1967Upgrade.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 {
                                    _upgradeTo(newImplementation);
                                    if (data.length > 0 || forceCall) {
                                        Address.functionDelegateCall(newImplementation, data);
                                    }
                                }
                                /**
                                 * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function _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
                                        _upgradeTo(newImplementation);
                                    }
                                }
                                /**
                                 * @dev Storage slot with the admin of the contract.
                                 * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                                /**
                                 * @dev Emitted when the admin account has changed.
                                 */
                                event AdminChanged(address previousAdmin, address newAdmin);
                                /**
                                 * @dev Returns the current admin.
                                 */
                                function _getAdmin() internal view returns (address) {
                                    return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new address in the EIP1967 admin slot.
                                 */
                                function _setAdmin(address newAdmin) private {
                                    require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                                    StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
                                }
                                /**
                                 * @dev Changes the admin of the proxy.
                                 *
                                 * Emits an {AdminChanged} event.
                                 */
                                function _changeAdmin(address newAdmin) internal {
                                    emit AdminChanged(_getAdmin(), newAdmin);
                                    _setAdmin(newAdmin);
                                }
                                /**
                                 * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
                                 * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
                                 */
                                bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
                                /**
                                 * @dev Emitted when the beacon is upgraded.
                                 */
                                event BeaconUpgraded(address indexed beacon);
                                /**
                                 * @dev Returns the current beacon.
                                 */
                                function _getBeacon() internal view returns (address) {
                                    return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new beacon in the EIP1967 beacon slot.
                                 */
                                function _setBeacon(address newBeacon) private {
                                    require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                                    require(
                                        Address.isContract(IBeacon(newBeacon).implementation()),
                                        "ERC1967: beacon implementation is not a contract"
                                    );
                                    StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
                                }
                                /**
                                 * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
                                 * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
                                 *
                                 * Emits a {BeaconUpgraded} event.
                                 */
                                function _upgradeBeaconToAndCall(
                                    address newBeacon,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    _setBeacon(newBeacon);
                                    emit BeaconUpgraded(newBeacon);
                                    if (data.length > 0 || forceCall) {
                                        Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
                                    }
                                }
                            }
                            /**
                             * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
                             * implementation address that can be changed. This address is stored in storage in the location specified by
                             * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
                             * implementation behind the proxy.
                             */
                            contract ERC1967Proxy is Proxy, ERC1967Upgrade {
                                /**
                                 * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                                 *
                                 * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                                 * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                                 */
                                constructor(address _logic, bytes memory _data) payable {
                                    assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                                    _upgradeToAndCall(_logic, _data, false);
                                }
                                /**
                                 * @dev Returns the current implementation address.
                                 */
                                function _implementation() internal view virtual override returns (address impl) {
                                    return ERC1967Upgrade._getImplementation();
                                }
                            }
                            // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
                            /**
                             * @dev This is the interface that {BeaconProxy} expects of its beacon.
                             */
                            interface IBeacon {
                                /**
                                 * @dev Must return an address that can be used as a delegate call target.
                                 *
                                 * {BeaconProxy} will check that this address is a contract.
                                 */
                                function implementation() external view returns (address);
                            }
                            // OpenZeppelin Contracts 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);
                                        }
                                    }
                                }
                            }
                            // OpenZeppelin Contracts v4.4.1 (utils/StorageSlot.sol)
                            /**
                             * @dev Library for reading and writing primitive types to specific storage slots.
                             *
                             * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
                             * This library helps with reading and writing to such slots without the need for inline assembly.
                             *
                             * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
                             *
                             * Example usage to set ERC1967 implementation slot:
                             * ```
                             * contract ERC1967 {
                             *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                             *
                             *     function _getImplementation() internal view returns (address) {
                             *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                             *     }
                             *
                             *     function _setImplementation(address newImplementation) internal {
                             *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                             *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                             *     }
                             * }
                             * ```
                             *
                             * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
                             */
                            library StorageSlot {
                                struct AddressSlot {
                                    address value;
                                }
                                struct BooleanSlot {
                                    bool value;
                                }
                                struct Bytes32Slot {
                                    bytes32 value;
                                }
                                struct Uint256Slot {
                                    uint256 value;
                                }
                                /**
                                 * @dev Returns an `AddressSlot` with member `value` located at `slot`.
                                 */
                                function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
                                 */
                                function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
                                 */
                                function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
                                 */
                                function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                            }

                            File 2 of 6: LilPudgys
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "./ERC721.sol";
                            import "@openzeppelin/contracts/access/Ownable.sol";
                            import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
                            import "./PudgyPenguinsInterface.sol";
                            import "./WithdrawFairly.sol";
                            // @author: miinded.com
                            ////////////////////////////////////////////////////////////////
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                                                            //
                            //                         =-:*=.                             //
                            //                         #@@@@@@*:                          //
                            //                      .+%@@@@@@@@@@*:                       //
                            //                     -@@@@@@@@@@@@@@@*                      //
                            //                    -@@@@@@@@@@@@@@@@@#                     //
                            //                    @@@@@@@@@@@@@@@@@@@:                    //
                            //                    @@@@@@@@@@@@@@@@@@@=                    //
                            //                  :#@@@@@@@@@@@@@@@@@@@@*.                  //
                            //                 *@@@@@@@@@@@@@@@@@@@@@@@@=                 //
                            //                #@@@@@@@@@@@@@@@@@@@@@@@@@@+                //
                            //               =@@@@@@@@@@@@@@@@@@@@@@@@@@@@.               //
                            //               #@##@@@@@@@@@@@@@@@@@@@@@%+#@=               //
                            //               =:  *@@@@@@@@@@@@@@@@@@@@.  =:               //
                            //                    #@@@@@@@@@@@@@@@@@@:                    //
                            //                     -%@@@@@@@@@@@@@@*                      //
                            //                       *@@@@@@@@@@@*                        //
                            //                      #@@@@@*:#@@@@%#                       //
                            ////////////////////////////////////////////////////////////////
                            contract LilPudgys is ERC721, Ownable, WithdrawFairly, ReentrancyGuard {
                                uint16 private _tokenIdTrackerReserve;
                                uint16 private _tokenIdTrackerAuction;
                                uint16 private _tokenIdTracker;
                                uint16 private _burnedTracker;
                                struct Dutch{
                                    uint256 start;
                                    uint256 duration;
                                    uint256 startPrice;
                                    uint256 endPrice;
                                }
                                uint256 public constant MAX_ELEMENTS = 22222; //  MAX_RESERVE + MAX_CLAIM + MAX_AUCTION
                                uint256 public constant MAX_CLAIM = 8888;
                                uint256 public constant MAX_RESERVE = 300;
                                uint256 public constant MAX_AUCTION = MAX_ELEMENTS - MAX_CLAIM - MAX_RESERVE;
                                uint256 public constant MAX_BY_MINT = 20;
                                uint256 public constant MAX_BY_CLAIM = 20;
                                Dutch public dutch;
                                bool public paused = false;
                                string public baseTokenURI;
                                PudgyPenguinsInterface public pudgyPenguins;
                                mapping (uint256 => bool) private _pudgyPenguinsUsed;
                                event MintLilPudgy(uint256 indexed id);
                                constructor(string memory baseURI, address _pudgyPenguins) ERC721("LilPudgys", "LP") {
                                    setBaseURI(baseURI);
                                    setPudgyPenguins(_pudgyPenguins);
                                    setDutch(Dutch(1639947600, 2 hours, 0.3 ether, 0.03 ether));
                                }
                                //******************************************************//
                                //                     Modifier                         //
                                //******************************************************//
                                modifier claimIsOpen {
                                    require(claimIsStarted(),"Dutch not ended");
                                    require(!paused, "Pausable: paused");
                                    _;
                                }
                                modifier saleIsOpen {
                                    require(dutchIsStarted(), "Dutch not started");
                                    require(!paused, "Pausable: paused");
                                    _;
                                }
                                //******************************************************//
                                //                     Mint                             //
                                //******************************************************//
                                function mint(uint256 _count) public payable saleIsOpen nonReentrant{
                                    require(_tokenIdTrackerAuction + _count <= MAX_AUCTION, "Sold Out!");
                                    require(_count <= MAX_BY_MINT, "Exceeds number");
                                    require(msg.value >= price(_count), "Value below price");
                                    for (uint256 i = 0; i < _count; i++) {
                                        _mintToken(_msgSender(), MAX_CLAIM + MAX_RESERVE + _tokenIdTrackerAuction);
                                        _tokenIdTrackerAuction += 1;
                                    }
                                }
                                function claim(uint256[] memory _tokensId) public claimIsOpen {
                                    require(_tokensId.length <= MAX_BY_CLAIM, "Exceeds number");
                                    for (uint256 i = 0; i < _tokensId.length; i++) {
                                        require(canClaim(_tokensId[i]) && pudgyPenguins.ownerOf(_tokensId[i]) == _msgSender(), "Bad owner!");
                                        _pudgyPenguinsUsed[_tokensId[i]] = true;
                                        _mintToken(_msgSender(), _tokensId[i]);
                                    }
                                }
                                function canClaim(uint256 _tokenId) public view returns(bool) {
                                    return _pudgyPenguinsUsed[_tokenId] == false;
                                }
                                function _mintToken(address _to, uint256 id) private {
                                    _tokenIdTracker += 1;
                                    _safeMint(_to, id);
                                    emit MintLilPudgy(id);
                                }
                                function reserve(uint256 _count) public onlyOwner {
                                    require(_tokenIdTrackerReserve + _count <= MAX_RESERVE, "Exceeded giveaways.");
                                    for (uint256 i = 0; i < _count; i++) {
                                        _mintToken(_msgSender(), MAX_CLAIM + _tokenIdTrackerReserve);
                                        _tokenIdTrackerReserve += 1;
                                    }
                                }
                                //******************************************************//
                                //                      Dutch                           //
                                //******************************************************//
                                function claimIsStarted() public view returns(bool){
                                    return getMintPrice(0) == dutch.endPrice;
                                }
                                function dutchIsStarted() public view returns(bool){
                                    return block.timestamp >= dutch.start;
                                }
                                function getMintPrice(uint256 _timestamp) public view returns (uint256) {
                                    if (!dutchIsStarted()){
                                        return dutch.startPrice;
                                    }
                                    _timestamp = _timestamp == 0 ? block.timestamp : _timestamp;
                                    uint256 duration = _timestamp - dutch.start;
                                    if(duration >= dutch.duration){
                                        return dutch.endPrice;
                                    }
                                    uint256 currentPrice = dutch.startPrice - ((((duration * 100000) / dutch.duration) * (dutch.startPrice - dutch.endPrice)) / 100000);
                                    return  currentPrice > dutch.endPrice ? currentPrice : dutch.endPrice;
                                }
                                //******************************************************//
                                //                      Getters                         //
                                //******************************************************//
                                function totalSupply() public view returns(uint256){
                                    return _tokenIdTracker - _burnedTracker;
                                }
                                function price(uint256 _count) public view returns (uint256) {
                                    return getMintPrice(0) * _count;
                                }
                                function _baseURI() internal view virtual override returns (string memory) {
                                    return baseTokenURI;
                                }
                                function walletOfOwner(address _owner) external view returns (uint256[] memory) {
                                    uint256 tokenCount = balanceOf(_owner);
                                    uint256[] memory tokensId = new uint256[](tokenCount);
                                    if(tokenCount == 0){
                                        return tokensId;
                                    }
                                    uint256 key = 0;
                                    for (uint256 i = 0; i < MAX_ELEMENTS; i++) {
                                        if(rawOwnerOf(i) == _owner){
                                            tokensId[key] = i;
                                            key++;
                                            if(key == tokenCount){break;}
                                        }
                                    }
                                    return tokensId;
                                }
                                function setPause(bool _toggle) public onlyOwner {
                                    paused = _toggle;
                                }
                                //******************************************************//
                                //                      Setters                         //
                                //******************************************************//
                                function setPudgyPenguins(address _pudgyPenguins) public onlyOwner {
                                    pudgyPenguins = PudgyPenguinsInterface(_pudgyPenguins);
                                }
                                function setBaseURI(string memory baseURI) public onlyOwner {
                                    baseTokenURI = baseURI;
                                }
                                function setDutch(Dutch memory _dutch) public onlyOwner {
                                    dutch = _dutch;
                                }
                                //******************************************************//
                                //                      Burn                            //
                                //******************************************************//
                                function burn(uint256 _tokenId) public virtual {
                                    require(_isApprovedOrOwner(_msgSender(), _tokenId), "Not owner nor approved");
                                    _burnedTracker += 1;
                                    _burn(_tokenId);
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                            import "@openzeppelin/contracts/access/Ownable.sol";
                            import "@openzeppelin/contracts/utils/math/SafeMath.sol";
                            contract WithdrawFairly is Ownable {
                                using SafeMath for uint256;
                                struct Part {
                                    address salesWallet;
                                    address royaltiesWallet;
                                    uint256 salePart;
                                    uint256 royaltiesPart;
                                }
                                Part[] public parts;
                                address[] public tokenAddress;
                                constructor(){
                                    parts.push(Part(0xb224811F71c803af1762CC6AEfd995edbfAFBD42, 0x647b14eC32Cd079D4156241c990Cc73540FFad5b, 2000, 3500)); // miinded
                                    parts.push(Part(0xAA3F3ed871aB321002d823D466D6E2d5e05E4aB2, 0xAA3F3ed871aB321002d823D466D6E2d5e05E4aB2, 2000, 1625)); // pudgy 1
                                    parts.push(Part(0x70031E2B0F221da3b72b305292219d7DCD1300Df, 0x70031E2B0F221da3b72b305292219d7DCD1300Df, 2000, 1625)); // pudgy 2
                                    parts.push(Part(0x462A7C08f7f6Dd914F913CD82b4d5f16D1aa350c, 0x462A7C08f7f6Dd914F913CD82b4d5f16D1aa350c, 2000, 1625)); // pudgy 3
                                    parts.push(Part(0xFe5573C66273313034F7fF6050c54b5402553716, 0xFe5573C66273313034F7fF6050c54b5402553716, 2000, 1625)); // pudgy 4
                                    tokenAddress.push(0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48); // USDC
                                    tokenAddress.push(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2); // WETH
                                    tokenAddress.push(0x6B175474E89094C44Da98b954EedeAC495271d0F); // DAI
                                }
                                function withdrawSalesPart() public onlyOwner {
                                    uint256 balance = address(this).balance;
                                    require(balance > 0, "Sales Balance = 0");
                                    for(uint8 i = 0; i < parts.length; i++){
                                        if(parts[i].salePart > 0){
                                            _withdraw(parts[i].salesWallet, balance.mul(parts[i].salePart).div(10000));
                                        }
                                    }
                                    _withdraw(owner(), address(this).balance);
                                }
                                function withdrawRoyalties() public onlyOwner {
                                    uint256 balance = address(this).balance;
                                    require(balance > 0, "Contract Balance = 0");
                                    for(uint8 i = 0; i < parts.length; i++){
                                        if(parts[i].royaltiesPart > 0){
                                            _withdraw(parts[i].royaltiesWallet, balance.mul(parts[i].royaltiesPart).div(10000));
                                        }
                                    }
                                    _withdraw(owner(), address(this).balance);
                                }
                                function _withdraw(address _address, uint256 _amount) private {
                                    (bool success, ) = _address.call{value: _amount}("");
                                    require(success, "Transfer failed.");
                                }
                                function withdrawRoyaltiesTokens() public onlyOwner {
                                    for(uint256 j = 0; j < tokenAddress.length; j++){
                                        if(tokenAddress[j] == address(0)){
                                            continue;
                                        }
                                        uint256 balance = IERC20(tokenAddress[j]).balanceOf(address(this));
                                        for(uint256 i = 0; i < parts.length; i++){
                                            if(parts[i].royaltiesPart > 0 && balance > 0){
                                                IERC20(tokenAddress[j]).transfer(parts[i].royaltiesWallet, balance.mul(parts[i].royaltiesPart).div(10000));
                                            }
                                        }
                                    }
                                }
                                function addERC20Address(address _contract) public onlyOwner{
                                    tokenAddress.push(_contract);
                                }
                                function removeERC20Address(address _contract) public onlyOwner{
                                    for(uint256 i = 0; i < tokenAddress.length;i++){
                                        if(tokenAddress[i] == _contract){
                                            tokenAddress[i] = address(0);
                                        }
                                    }
                                }
                                receive() external payable {}
                            }// SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
                            interface PudgyPenguinsInterface is IERC721{
                                function walletOfOwner(address _owner) external view returns (uint256[] memory);
                            }// SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
                            import "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol";
                            import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol";
                            import "@openzeppelin/contracts/utils/Address.sol";
                            import "@openzeppelin/contracts/utils/Context.sol";
                            import "@openzeppelin/contracts/utils/Strings.sol";
                            import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
                            /**
                             * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
                             * the Metadata extension, but not including the Enumerable extension, which is available separately as
                             * {ERC721Enumerable}.
                             */
                            contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
                                using Address for address;
                                using Strings for uint256;
                                // Token name
                                string private _name;
                                // Token symbol
                                string private _symbol;
                                // Mapping from token ID to owner address
                                mapping(uint256 => address) private _owners;
                                // Mapping owner address to token count
                                mapping(address => uint256) private _balances;
                                // 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;
                                /**
                                 * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
                                 */
                                constructor(string memory name_, string memory symbol_) {
                                    _name = name_;
                                    _symbol = symbol_;
                                }
                                /**
                                 * @dev See {IERC165-supportsInterface}.
                                 */
                                function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
                                    return
                                    interfaceId == type(IERC721).interfaceId ||
                                    interfaceId == type(IERC721Metadata).interfaceId ||
                                    super.supportsInterface(interfaceId);
                                }
                                /**
                                 * @dev See {IERC721-balanceOf}.
                                 */
                                function balanceOf(address owner) public view virtual override returns (uint256) {
                                    require(owner != address(0), "ERC721: balance query for the zero address");
                                    return _balances[owner];
                                }
                                /**
                                 * @dev See {IERC721-ownerOf}.
                                 */
                                function ownerOf(uint256 tokenId) public view virtual override returns (address) {
                                    address owner = _owners[tokenId];
                                    require(owner != address(0), "ERC721: owner query for nonexistent token");
                                    return owner;
                                }
                                /**
                                 * @dev Edit for rawOwnerOf token
                                 */
                                function rawOwnerOf(uint256 tokenId) public view returns (address) {
                                    return _owners[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) {
                                    require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");
                                    string memory baseURI = _baseURI();
                                    return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
                                }
                                /**
                                 * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
                                 * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
                                 * by default, can be overriden in child contracts.
                                 */
                                function _baseURI() internal view virtual returns (string memory) {
                                    return "";
                                }
                                /**
                                 * @dev See {IERC721-approve}.
                                 */
                                function approve(address to, uint256 tokenId) public virtual override {
                                    address owner = ERC721.ownerOf(tokenId);
                                    require(to != owner, "ERC721: approval to current owner");
                                    require(
                                        _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
                                        "ERC721: approve caller is not owner nor approved for all"
                                    );
                                    _approve(to, tokenId);
                                }
                                /**
                                 * @dev See {IERC721-getApproved}.
                                 */
                                function getApproved(uint256 tokenId) public view virtual override returns (address) {
                                    require(_exists(tokenId), "ERC721: approved query for nonexistent token");
                                    return _tokenApprovals[tokenId];
                                }
                                /**
                                 * @dev See {IERC721-setApprovalForAll}.
                                 */
                                function setApprovalForAll(address operator, bool approved) public virtual override {
                                    require(operator != _msgSender(), "ERC721: approve to caller");
                                    _operatorApprovals[_msgSender()][operator] = approved;
                                    emit ApprovalForAll(_msgSender(), operator, approved);
                                }
                                /**
                                 * @dev See {IERC721-isApprovedForAll}.
                                 */
                                function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
                                    return _operatorApprovals[owner][operator];
                                }
                                /**
                                 * @dev See {IERC721-transferFrom}.
                                 */
                                function transferFrom(
                                    address from,
                                    address to,
                                    uint256 tokenId
                                ) public virtual override {
                                    //solhint-disable-next-line max-line-length
                                    require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
                                    _transfer(from, to, tokenId);
                                }
                                /**
                                 * @dev See {IERC721-safeTransferFrom}.
                                 */
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 tokenId
                                ) public virtual override {
                                    safeTransferFrom(from, to, tokenId, "");
                                }
                                /**
                                 * @dev See {IERC721-safeTransferFrom}.
                                 */
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 tokenId,
                                    bytes memory _data
                                ) public virtual override {
                                    require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
                                    _safeTransfer(from, to, tokenId, _data);
                                }
                                /**
                                 * @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.
                                 *
                                 * `_data` is additional data, it has no specified format and it is sent in call to `to`.
                                 *
                                 * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
                                 * implement alternative mechanisms to perform token transfer, such as signature-based.
                                 *
                                 * Requirements:
                                 *
                                 * - `from` cannot be the zero address.
                                 * - `to` cannot be the zero address.
                                 * - `tokenId` token must exist and be owned by `from`.
                                 * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                                 *
                                 * Emits a {Transfer} event.
                                 */
                                function _safeTransfer(
                                    address from,
                                    address to,
                                    uint256 tokenId,
                                    bytes memory _data
                                ) internal virtual {
                                    _transfer(from, to, tokenId);
                                    require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
                                }
                                /**
                                 * @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`),
                                 * and stop existing when they are burned (`_burn`).
                                 */
                                function _exists(uint256 tokenId) internal view virtual returns (bool) {
                                    return _owners[tokenId] != address(0);
                                }
                                /**
                                 * @dev Returns whether `spender` is allowed to manage `tokenId`.
                                 *
                                 * Requirements:
                                 *
                                 * - `tokenId` must exist.
                                 */
                                function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
                                    require(_exists(tokenId), "ERC721: operator query for nonexistent token");
                                    address owner = ERC721.ownerOf(tokenId);
                                    return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));
                                }
                                /**
                                 * @dev Safely mints `tokenId` and transfers it to `to`.
                                 *
                                 * Requirements:
                                 *
                                 * - `tokenId` must not exist.
                                 * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                                 *
                                 * Emits a {Transfer} event.
                                 */
                                function _safeMint(address to, uint256 tokenId) internal virtual {
                                    _safeMint(to, tokenId, "");
                                }
                                /**
                                 * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
                                 * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
                                 */
                                function _safeMint(
                                    address to,
                                    uint256 tokenId,
                                    bytes memory _data
                                ) internal virtual {
                                    _mint(to, tokenId);
                                    require(
                                        _checkOnERC721Received(address(0), to, tokenId, _data),
                                        "ERC721: transfer to non ERC721Receiver implementer"
                                    );
                                }
                                /**
                                 * @dev Mints `tokenId` and transfers it to `to`.
                                 *
                                 * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
                                 *
                                 * Requirements:
                                 *
                                 * - `tokenId` must not exist.
                                 * - `to` cannot be the zero address.
                                 *
                                 * Emits a {Transfer} event.
                                 */
                                function _mint(address to, uint256 tokenId) internal virtual {
                                    require(to != address(0), "ERC721: mint to the zero address");
                                    require(!_exists(tokenId), "ERC721: token already minted");
                                    _beforeTokenTransfer(address(0), to, tokenId);
                                    _balances[to] += 1;
                                    _owners[tokenId] = to;
                                    emit Transfer(address(0), to, tokenId);
                                }
                                /**
                                 * @dev Destroys `tokenId`.
                                 * The approval is cleared when the token is burned.
                                 *
                                 * Requirements:
                                 *
                                 * - `tokenId` must exist.
                                 *
                                 * Emits a {Transfer} event.
                                 */
                                function _burn(uint256 tokenId) internal virtual {
                                    address owner = ERC721.ownerOf(tokenId);
                                    address to = address(0);
                                    _beforeTokenTransfer(owner, to, tokenId);
                                    // Clear approvals
                                    _approve(address(0), tokenId);
                                    _balances[owner] -= 1;
                                    delete _owners[tokenId];
                                    emit Transfer(owner, to, tokenId);
                                }
                                /**
                                 * @dev Transfers `tokenId` from `from` to `to`.
                                 *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
                                 *
                                 * Requirements:
                                 *
                                 * - `to` cannot be the zero address.
                                 * - `tokenId` token must be owned by `from`.
                                 *
                                 * Emits a {Transfer} event.
                                 */
                                function _transfer(
                                    address from,
                                    address to,
                                    uint256 tokenId
                                ) internal virtual {
                                    require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer of token that is not own");
                                    require(to != address(0), "ERC721: transfer to the zero address");
                                    _beforeTokenTransfer(from, to, tokenId);
                                    // Clear approvals from the previous owner
                                    _approve(address(0), tokenId);
                                    _balances[from] -= 1;
                                    _balances[to] += 1;
                                    _owners[tokenId] = to;
                                    emit Transfer(from, to, tokenId);
                                }
                                /**
                                 * @dev Approve `to` to operate on `tokenId`
                                 *
                                 * Emits a {Approval} event.
                                 */
                                function _approve(address to, uint256 tokenId) internal virtual {
                                    _tokenApprovals[tokenId] = to;
                                    emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
                                }
                                /**
                                 * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
                                 * The call is not executed if the target address is not a 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 _checkOnERC721Received(
                                    address from,
                                    address to,
                                    uint256 tokenId,
                                    bytes memory _data
                                ) private returns (bool) {
                                    if (to.isContract()) {
                                        try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
                                            return retval == IERC721Receiver(to).onERC721Received.selector;
                                        } catch (bytes memory reason) {
                                            if (reason.length == 0) {
                                                revert("ERC721: transfer to non ERC721Receiver implementer");
                                            } else {
                                                assembly {
                                                    revert(add(32, reason), mload(reason))
                                                }
                                            }
                                        }
                                    } else {
                                        return true;
                                    }
                                }
                                /**
                                 * @dev Hook that is called before any token transfer. This includes minting
                                 * and burning.
                                 *
                                 * 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, ``from``'s `tokenId` will be burned.
                                 * - `from` and `to` are never both zero.
                                 *
                                 * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                                 */
                                function _beforeTokenTransfer(
                                    address from,
                                    address to,
                                    uint256 tokenId
                                ) internal virtual {}
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (utils/math/SafeMath.sol)
                            pragma solidity ^0.8.0;
                            // CAUTION
                            // This version of SafeMath should only be used with Solidity 0.8 or later,
                            // because it relies on the compiler's built in overflow checks.
                            /**
                             * @dev Wrappers over Solidity's arithmetic operations.
                             *
                             * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
                             * now has built in overflow checking.
                             */
                            library SafeMath {
                                /**
                                 * @dev Returns the addition of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    unchecked {
                                        uint256 c = a + b;
                                        if (c < a) return (false, 0);
                                        return (true, c);
                                    }
                                }
                                /**
                                 * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    unchecked {
                                        if (b > a) return (false, 0);
                                        return (true, a - b);
                                    }
                                }
                                /**
                                 * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    unchecked {
                                        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                                        // benefit is lost if 'b' is also tested.
                                        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                                        if (a == 0) return (true, 0);
                                        uint256 c = a * b;
                                        if (c / a != b) return (false, 0);
                                        return (true, c);
                                    }
                                }
                                /**
                                 * @dev Returns the division of two unsigned integers, with a division by zero flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    unchecked {
                                        if (b == 0) return (false, 0);
                                        return (true, a / b);
                                    }
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    unchecked {
                                        if (b == 0) return (false, 0);
                                        return (true, a % b);
                                    }
                                }
                                /**
                                 * @dev Returns the addition of two unsigned integers, reverting on
                                 * overflow.
                                 *
                                 * Counterpart to Solidity's `+` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Addition cannot overflow.
                                 */
                                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                                    return a + b;
                                }
                                /**
                                 * @dev Returns the subtraction of two unsigned integers, reverting on
                                 * overflow (when the result is negative).
                                 *
                                 * Counterpart to Solidity's `-` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Subtraction cannot overflow.
                                 */
                                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                                    return a - b;
                                }
                                /**
                                 * @dev Returns the multiplication of two unsigned integers, reverting on
                                 * overflow.
                                 *
                                 * Counterpart to Solidity's `*` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Multiplication cannot overflow.
                                 */
                                function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                                    return a * b;
                                }
                                /**
                                 * @dev Returns the integer division of two unsigned integers, reverting on
                                 * division by zero. The result is rounded towards zero.
                                 *
                                 * Counterpart to Solidity's `/` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function div(uint256 a, uint256 b) internal pure returns (uint256) {
                                    return a / b;
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                                 * reverting when dividing by zero.
                                 *
                                 * Counterpart to Solidity's `%` operator. This function uses a `revert`
                                 * opcode (which leaves remaining gas untouched) while Solidity uses an
                                 * invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                                    return a % b;
                                }
                                /**
                                 * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                                 * overflow (when the result is negative).
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {trySub}.
                                 *
                                 * Counterpart to Solidity's `-` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Subtraction cannot overflow.
                                 */
                                function sub(
                                    uint256 a,
                                    uint256 b,
                                    string memory errorMessage
                                ) internal pure returns (uint256) {
                                    unchecked {
                                        require(b <= a, errorMessage);
                                        return a - b;
                                    }
                                }
                                /**
                                 * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                                 * division by zero. The result is rounded towards zero.
                                 *
                                 * Counterpart to Solidity's `/` operator. Note: this function uses a
                                 * `revert` opcode (which leaves remaining gas untouched) while Solidity
                                 * uses an invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function div(
                                    uint256 a,
                                    uint256 b,
                                    string memory errorMessage
                                ) internal pure returns (uint256) {
                                    unchecked {
                                        require(b > 0, errorMessage);
                                        return a / b;
                                    }
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                                 * reverting with custom message when dividing by zero.
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {tryMod}.
                                 *
                                 * Counterpart to Solidity's `%` operator. This function uses a `revert`
                                 * opcode (which leaves remaining gas untouched) while Solidity uses an
                                 * invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function mod(
                                    uint256 a,
                                    uint256 b,
                                    string memory errorMessage
                                ) internal pure returns (uint256) {
                                    unchecked {
                                        require(b > 0, errorMessage);
                                        return a % b;
                                    }
                                }
                            }
                            // 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 (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/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/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/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 (token/ERC721/extensions/IERC721Metadata.sol)
                            pragma solidity ^0.8.0;
                            import "../IERC721.sol";
                            /**
                             * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
                             * @dev See https://eips.ethereum.org/EIPS/eip-721
                             */
                            interface IERC721Metadata is IERC721 {
                                /**
                                 * @dev Returns the token collection name.
                                 */
                                function name() external view returns (string memory);
                                /**
                                 * @dev Returns the token collection symbol.
                                 */
                                function symbol() external view returns (string memory);
                                /**
                                 * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
                                 */
                                function tokenURI(uint256 tokenId) external view returns (string memory);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts 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 (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/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 (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 (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);
                                }
                            }
                            

                            File 3 of 6: Blend
                            // SPDX-License-Identifier: BSL 1.1 - Blend (c) Non Fungible Trading Ltd.
                            pragma solidity 0.8.17;
                            import "lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/UUPSUpgradeable.sol";
                            import "./Helpers.sol";
                            import "./lib/Structs.sol";
                            import "./OfferController.sol";
                            import "./interfaces/IBlend.sol";
                            import "../pool/interfaces/IBlurPool.sol";
                            contract Blend is IBlend, OfferController, UUPSUpgradeable {
                                IExchange private immutable _EXCHANGE;
                                IExchangeV2 private immutable _EXCHANGE_V2;
                                IBlurPool private immutable _POOL;
                                address private immutable _SELL_MATCHING_POLICY;
                                address private immutable _BID_MATCHING_POLICY;
                                address private immutable _DELEGATE;
                                address private immutable _DELEGATE_V2;
                                uint256 private constant _BASIS_POINTS = 10_000;
                                uint256 private constant _MAX_AUCTION_DURATION = 432_000;
                                uint256 private constant _LIQUIDATION_THRESHOLD = 100_000;
                                uint256 private _nextLienId;
                                mapping(uint256 => bytes32) public liens;
                                mapping(bytes32 => uint256) public amountTaken;
                                // required by the OZ UUPS module
                                function _authorizeUpgrade(address) internal override onlyOwner {}
                                constructor(
                                    address pool,
                                    address exchange,
                                    address exchangeV2,
                                    address sellMatchingPolicy,
                                    address bidMatchingPolicy,
                                    address delegate,
                                    address delegateV2
                                ) {
                                    _POOL = IBlurPool(pool);
                                    _EXCHANGE = IExchange(exchange);
                                    _EXCHANGE_V2 = IExchangeV2(exchangeV2);
                                    _SELL_MATCHING_POLICY = sellMatchingPolicy;
                                    _BID_MATCHING_POLICY = bidMatchingPolicy;
                                    _DELEGATE = delegate;
                                    _DELEGATE_V2 = delegateV2;
                                    _disableInitializers();
                                }
                                function initialize() external initializer {
                                    __UUPSUpgradeable_init();
                                    __Ownable_init();
                                }
                                /*//////////////////////////////////////////////////
                                                BORROW FLOWS
                                //////////////////////////////////////////////////*/
                                /**
                                 * @notice Verifies and takes loan offer; then transfers loan and collateral assets
                                 * @param offer Loan offer
                                 * @param signature Lender offer signature
                                 * @param loanAmount Loan amount in ETH
                                 * @param collateralTokenId Token id to provide as collateral
                                 * @return lienId New lien id
                                 */
                                function borrow(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    uint256 collateralTokenId
                                ) external returns (uint256 lienId) {
                                    lienId = _borrow(offer, signature, loanAmount, collateralTokenId);
                                    /* Lock collateral token. */
                                    offer.collection.safeTransferFrom(msg.sender, address(this), collateralTokenId);
                                    /* Transfer loan to borrower. */
                                    _POOL.transferFrom(offer.lender, msg.sender, loanAmount);
                                }
                                /**
                                 * @notice Repays loan and retrieves collateral
                                 * @param lien Lien preimage
                                 * @param lienId Lien id
                                 */
                                function repay(
                                    Lien calldata lien,
                                    uint256 lienId
                                ) external validateLien(lien, lienId) lienIsActive(lien) {
                                    uint256 debt = _repay(lien, lienId);
                                    /* Return NFT to borrower. */
                                    lien.collection.safeTransferFrom(address(this), lien.borrower, lien.tokenId);
                                    /* Repay loan to lender. */
                                    _POOL.transferFrom(msg.sender, lien.lender, debt);
                                }
                                /**
                                 * @notice Verifies and takes loan offer; creates new lien
                                 * @param offer Loan offer
                                 * @param signature Lender offer signature
                                 * @param loanAmount Loan amount in ETH
                                 * @param collateralTokenId Token id to provide as collateral
                                 * @return lienId New lien id
                                 */
                                function _borrow(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    uint256 collateralTokenId
                                ) internal returns (uint256 lienId) {
                                    if (offer.auctionDuration > _MAX_AUCTION_DURATION) {
                                        revert InvalidAuctionDuration();
                                    }
                                    Lien memory lien = Lien({
                                        lender: offer.lender,
                                        borrower: msg.sender,
                                        collection: offer.collection,
                                        tokenId: collateralTokenId,
                                        amount: loanAmount,
                                        startTime: block.timestamp,
                                        rate: offer.rate,
                                        auctionStartBlock: 0,
                                        auctionDuration: offer.auctionDuration
                                    });
                                    /* Create lien. */
                                    unchecked {
                                        liens[lienId = _nextLienId++] = keccak256(abi.encode(lien));
                                    }
                                    /* Take the loan offer. */
                                    _takeLoanOffer(offer, signature, lien, lienId);
                                }
                                /**
                                 * @notice Computes the current debt repayment and burns the lien
                                 * @dev Does not transfer assets
                                 * @param lien Lien preimage
                                 * @param lienId Lien id
                                 * @return debt Current amount of debt owed on the lien
                                 */
                                function _repay(Lien calldata lien, uint256 lienId) internal returns (uint256 debt) {
                                    debt = Helpers.computeCurrentDebt(lien.amount, lien.rate, lien.startTime);
                                    delete liens[lienId];
                                    emit Repay(lienId, address(lien.collection));
                                }
                                /**
                                 * @notice Verifies and takes loan offer
                                 * @dev Does not transfer loan and collateral assets; does not update lien hash
                                 * @param offer Loan offer
                                 * @param signature Lender offer signature
                                 * @param lien Lien preimage
                                 * @param lienId Lien id
                                 */
                                function _takeLoanOffer(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    Lien memory lien,
                                    uint256 lienId
                                ) internal {
                                    bytes32 hash = _hashOffer(offer);
                                    _validateOffer(
                                        hash,
                                        offer.lender,
                                        offer.oracle,
                                        signature,
                                        offer.expirationTime,
                                        offer.salt
                                    );
                                    if (offer.rate > _LIQUIDATION_THRESHOLD) {
                                        revert RateTooHigh();
                                    }
                                    if (lien.amount > offer.maxAmount || lien.amount < offer.minAmount) {
                                        revert InvalidLoan();
                                    }
                                    uint256 _amountTaken = amountTaken[hash];
                                    if (offer.totalAmount - _amountTaken < lien.amount) {
                                        revert InsufficientOffer();
                                    }
                                    unchecked {
                                        amountTaken[hash] = _amountTaken + lien.amount;
                                    }
                                    emit LoanOfferTaken(
                                        hash,
                                        lienId,
                                        address(offer.collection),
                                        lien.lender,
                                        lien.borrower,
                                        lien.amount,
                                        lien.rate,
                                        lien.tokenId,
                                        lien.auctionDuration
                                    );
                                }
                                /*//////////////////////////////////////////////////
                                                REFINANCING FLOWS
                                //////////////////////////////////////////////////*/
                                /**
                                 * @notice Starts Dutch Auction on lien ownership
                                 * @dev Must be called by lien owner
                                 * @param lienId Lien token id
                                 */
                                function startAuction(Lien calldata lien, uint256 lienId) external validateLien(lien, lienId) {
                                    if (msg.sender != lien.lender) {
                                        revert Unauthorized();
                                    }
                                    /* Cannot start if auction has already started. */
                                    if (lien.auctionStartBlock != 0) {
                                        revert AuctionIsActive();
                                    }
                                    /* Add auction start block to lien. */
                                    liens[lienId] = keccak256(
                                        abi.encode(
                                            Lien({
                                                lender: lien.lender,
                                                borrower: lien.borrower,
                                                collection: lien.collection,
                                                tokenId: lien.tokenId,
                                                amount: lien.amount,
                                                startTime: lien.startTime,
                                                rate: lien.rate,
                                                auctionStartBlock: block.number,
                                                auctionDuration: lien.auctionDuration
                                            })
                                        )
                                    );
                                    emit StartAuction(lienId, address(lien.collection));
                                }
                                /**
                                 * @notice Seizes collateral from defaulted lien, skipping liens that are not defaulted
                                 * @param lienPointers List of lien, lienId pairs
                                 */
                                function seize(LienPointer[] calldata lienPointers) external {
                                    uint256 length = lienPointers.length;
                                    for (uint256 i; i < length; ) {
                                        Lien calldata lien = lienPointers[i].lien;
                                        uint256 lienId = lienPointers[i].lienId;
                                        if (msg.sender != lien.lender) {
                                            revert Unauthorized();
                                        }
                                        if (!_validateLien(lien, lienId)) {
                                            revert InvalidLien();
                                        }
                                        /* Check that the auction has ended and lien is defaulted. */
                                        if (_lienIsDefaulted(lien)) {
                                            delete liens[lienId];
                                            /* Seize collateral to lender. */
                                            lien.collection.safeTransferFrom(address(this), lien.lender, lien.tokenId);
                                            emit Seize(lienId, address(lien.collection));
                                        }
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                }
                                /**
                                 * @notice Refinances to different loan amount and repays previous loan
                                 * @dev Must be called by lender; previous loan must be repaid with interest
                                 * @param lien Lien struct
                                 * @param lienId Lien id
                                 * @param offer Loan offer
                                 * @param signature Offer signatures
                                 */
                                function refinance(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    LoanOffer calldata offer,
                                    bytes calldata signature
                                ) external validateLien(lien, lienId) lienIsActive(lien) {
                                    if (msg.sender != lien.lender) {
                                        revert Unauthorized();
                                    }
                                    /* Interest rate must be at least as good as current. */
                                    if (offer.rate > lien.rate || offer.auctionDuration != lien.auctionDuration) {
                                        revert InvalidRefinance();
                                    }
                                    uint256 debt = Helpers.computeCurrentDebt(lien.amount, lien.rate, lien.startTime);
                                    _refinance(lien, lienId, debt, offer, signature);
                                    /* Repay initial loan. */
                                    _POOL.transferFrom(offer.lender, lien.lender, debt);
                                }
                                /**
                                 * @notice Refinance lien in auction at the current debt amount where the interest rate ceiling increases over time
                                 * @dev Interest rate must be lower than the interest rate ceiling
                                 * @param lien Lien struct
                                 * @param lienId Lien token id
                                 * @param rate Interest rate (in bips)
                                 * @dev Formula: https://www.desmos.com/calculator/urasr71dhb
                                 */
                                function refinanceAuction(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    uint256 rate
                                ) external validateLien(lien, lienId) auctionIsActive(lien) {
                                    /* Rate must be below current rate limit. */
                                    uint256 rateLimit = Helpers.calcRefinancingAuctionRate(
                                        lien.auctionStartBlock,
                                        lien.auctionDuration,
                                        lien.rate
                                    );
                                    if (rate > rateLimit) {
                                        revert RateTooHigh();
                                    }
                                    uint256 debt = Helpers.computeCurrentDebt(lien.amount, lien.rate, lien.startTime);
                                    /* Reset the lien with the new lender and interest rate. */
                                    liens[lienId] = keccak256(
                                        abi.encode(
                                            Lien({
                                                lender: msg.sender, // set new lender
                                                borrower: lien.borrower,
                                                collection: lien.collection,
                                                tokenId: lien.tokenId,
                                                amount: debt, // new loan begins with previous debt
                                                startTime: block.timestamp,
                                                rate: rate,
                                                auctionStartBlock: 0, // close the auction
                                                auctionDuration: lien.auctionDuration
                                            })
                                        )
                                    );
                                    emit Refinance(
                                        lienId,
                                        address(lien.collection),
                                        msg.sender,
                                        debt,
                                        rate,
                                        lien.auctionDuration
                                    );
                                    /* Repay the initial loan. */
                                    _POOL.transferFrom(msg.sender, lien.lender, debt);
                                }
                                /**
                                 * @notice Refinances to different loan amount and repays previous loan
                                 * @param lien Lien struct
                                 * @param lienId Lien id
                                 * @param offer Loan offer
                                 * @param signature Offer signatures
                                 */
                                function refinanceAuctionByOther(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    LoanOffer calldata offer,
                                    bytes calldata signature
                                ) external validateLien(lien, lienId) auctionIsActive(lien) {
                                    /* Rate must be below current rate limit and auction duration must be the same. */
                                    uint256 rateLimit = Helpers.calcRefinancingAuctionRate(
                                        lien.auctionStartBlock,
                                        lien.auctionDuration,
                                        lien.rate
                                    );
                                    if (offer.rate > rateLimit || offer.auctionDuration != lien.auctionDuration) {
                                        revert InvalidRefinance();
                                    }
                                    uint256 debt = Helpers.computeCurrentDebt(lien.amount, lien.rate, lien.startTime);
                                    _refinance(lien, lienId, debt, offer, signature);
                                    /* Repay initial loan. */
                                    _POOL.transferFrom(offer.lender, lien.lender, debt);
                                }
                                /**
                                 * @notice Refinances to different loan amount and repays previous loan
                                 * @dev Must be called by borrower; previous loan must be repaid with interest
                                 * @param lien Lien struct
                                 * @param lienId Lien id
                                 * @param loanAmount New loan amount
                                 * @param offer Loan offer
                                 * @param signature Offer signatures
                                 */
                                function borrowerRefinance(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    uint256 loanAmount,
                                    LoanOffer calldata offer,
                                    bytes calldata signature
                                ) external validateLien(lien, lienId) lienIsActive(lien) {
                                    if (msg.sender != lien.borrower) {
                                        revert Unauthorized();
                                    }
                                    if (offer.auctionDuration > _MAX_AUCTION_DURATION) {
                                        revert InvalidAuctionDuration();
                                    }
                                    _refinance(lien, lienId, loanAmount, offer, signature);
                                    uint256 debt = Helpers.computeCurrentDebt(lien.amount, lien.rate, lien.startTime);
                                    if (loanAmount >= debt) {
                                        /* If new loan is more than the previous, repay the initial loan and send the remaining to the borrower. */
                                        _POOL.transferFrom(offer.lender, lien.lender, debt);
                                        unchecked {
                                            _POOL.transferFrom(offer.lender, lien.borrower, loanAmount - debt);
                                        }
                                    } else {
                                        /* If new loan is less than the previous, borrower must supply the difference to repay the initial loan. */
                                        _POOL.transferFrom(offer.lender, lien.lender, loanAmount);
                                        unchecked {
                                            _POOL.transferFrom(lien.borrower, lien.lender, debt - loanAmount);
                                        }
                                    }
                                }
                                function _refinance(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    uint256 loanAmount,
                                    LoanOffer calldata offer,
                                    bytes calldata signature
                                ) internal {
                                    if (lien.collection != offer.collection) {
                                        revert CollectionsDoNotMatch();
                                    }
                                    /* Update lien with new loan details. */
                                    Lien memory newLien = Lien({
                                        lender: offer.lender, // set new lender
                                        borrower: lien.borrower,
                                        collection: lien.collection,
                                        tokenId: lien.tokenId,
                                        amount: loanAmount,
                                        startTime: block.timestamp,
                                        rate: offer.rate,
                                        auctionStartBlock: 0, // close the auction
                                        auctionDuration: offer.auctionDuration
                                    });
                                    liens[lienId] = keccak256(abi.encode(newLien));
                                    /* Take the loan offer. */
                                    _takeLoanOffer(offer, signature, newLien, lienId);
                                    emit Refinance(
                                        lienId,
                                        address(offer.collection),
                                        offer.lender,
                                        loanAmount,
                                        offer.rate,
                                        offer.auctionDuration
                                    );
                                }
                                /*/////////////////////////////////////////////////////////////
                                                      MARKETPLACE FLOWS
                                /////////////////////////////////////////////////////////////*/
                                /**
                                 * @notice Purchase an NFT and use as collateral for a loan
                                 * @param offer Loan offer to take
                                 * @param signature Lender offer signature
                                 * @param loanAmount Loan amount in ETH
                                 * @param execution Marketplace execution data
                                 * @return lienId Lien id
                                 */
                                function buyToBorrow(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    ExecutionV1 calldata execution
                                ) public returns (uint256 lienId) {
                                    if (execution.makerOrder.order.trader == address(this)) {
                                        revert Unauthorized();
                                    }
                                    if (offer.auctionDuration > _MAX_AUCTION_DURATION) {
                                        revert InvalidAuctionDuration();
                                    }
                                    uint256 collateralTokenId = execution.makerOrder.order.tokenId;
                                    uint256 price = execution.makerOrder.order.price;
                                    /* Create lien. */
                                    Lien memory lien = Lien({
                                        lender: offer.lender,
                                        borrower: msg.sender,
                                        collection: offer.collection,
                                        tokenId: collateralTokenId,
                                        amount: loanAmount,
                                        startTime: block.timestamp,
                                        rate: offer.rate,
                                        auctionStartBlock: 0,
                                        auctionDuration: offer.auctionDuration
                                    });
                                    unchecked {
                                        liens[lienId = _nextLienId++] = keccak256(abi.encode(lien));
                                    }
                                    /* Take the loan offer. */
                                    _takeLoanOffer(offer, signature, lien, lienId);
                                    /* Create the buy side order coming from Blend. */
                                    Helpers.executeTakeAsk(
                                        offer,
                                        execution,
                                        loanAmount,
                                        collateralTokenId,
                                        price,
                                        _POOL,
                                        _EXCHANGE,
                                        _SELL_MATCHING_POLICY
                                    );
                                }
                                function buyToBorrowV2(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    AskExecutionV2 calldata execution
                                ) public returns (uint256 lienId) {
                                    if (offer.auctionDuration > _MAX_AUCTION_DURATION) {
                                        revert InvalidAuctionDuration();
                                    }
                                    uint256 collateralTokenId = execution.listing.tokenId;
                                    uint256 price = execution.listing.price;
                                    /* Create lien. */
                                    Lien memory lien = Lien({
                                        lender: offer.lender,
                                        borrower: msg.sender,
                                        collection: offer.collection,
                                        tokenId: collateralTokenId,
                                        amount: loanAmount,
                                        startTime: block.timestamp,
                                        rate: offer.rate,
                                        auctionStartBlock: 0,
                                        auctionDuration: offer.auctionDuration
                                    });
                                    unchecked {
                                        liens[lienId = _nextLienId++] = keccak256(abi.encode(lien));
                                    }
                                    /* Take the loan offer. */
                                    _takeLoanOffer(offer, signature, lien, lienId);
                                    /* Execute order using ETH currently in contract. */
                                    Helpers.executeTakeAskV2(
                                        offer,
                                        execution,
                                        loanAmount,
                                        collateralTokenId,
                                        price,
                                        _POOL,
                                        _EXCHANGE_V2
                                    );
                                }
                                /**
                                 * @notice Purchase a locked NFT; repay the initial loan; lock the token as collateral for a new loan
                                 * @param lien Lien preimage struct
                                 * @param sellInput Sell offer and signature
                                 * @param loanInput Loan offer and signature
                                 * @return lienId Lien id
                                 */
                                function buyToBorrowLocked(
                                    Lien calldata lien,
                                    SellInput calldata sellInput,
                                    LoanInput calldata loanInput,
                                    uint256 loanAmount
                                )
                                    public
                                    validateLien(lien, sellInput.offer.lienId)
                                    lienIsActive(lien)
                                    returns (uint256 lienId)
                                {
                                    if (lien.collection != loanInput.offer.collection) {
                                        revert CollectionsDoNotMatch();
                                    }
                                    (uint256 priceAfterFees, uint256 debt) = _buyLocked(
                                        lien,
                                        sellInput.offer,
                                        sellInput.signature
                                    );
                                    lienId = _borrow(loanInput.offer, loanInput.signature, loanAmount, lien.tokenId);
                                    /* Transfer funds. */
                                    /* Need to repay the original loan and payout any surplus from the sell or loan funds. */
                                    if (loanAmount < debt) {
                                        /* loanAmount < debt < priceAfterFees */
                                        /* Repay loan with funds from new lender to old lender. */
                                        _POOL.transferFrom(loanInput.offer.lender, lien.lender, loanAmount); // doesn't cover debt
                                        unchecked {
                                            /* Supplement difference from new borrower. */
                                            _POOL.transferFrom(msg.sender, lien.lender, debt - loanAmount); // cover rest of debt
                                            /* Send rest of sell funds to borrower. */
                                            _POOL.transferFrom(msg.sender, sellInput.offer.borrower, priceAfterFees - debt);
                                        }
                                    } else if (loanAmount < priceAfterFees) {
                                        /* debt < loanAmount < priceAfterFees */
                                        /* Repay loan with funds from new lender to old lender. */
                                        _POOL.transferFrom(loanInput.offer.lender, lien.lender, debt);
                                        unchecked {
                                            /* Send rest of loan from new lender to old borrower. */
                                            _POOL.transferFrom(
                                                loanInput.offer.lender,
                                                sellInput.offer.borrower,
                                                loanAmount - debt
                                            );
                                            /* Send rest of sell funds from new borrower to old borrower. */
                                            _POOL.transferFrom(
                                                msg.sender,
                                                sellInput.offer.borrower,
                                                priceAfterFees - loanAmount
                                            );
                                        }
                                    } else {
                                        /* debt < priceAfterFees < loanAmount */
                                        /* Repay loan with funds from new lender to old lender. */
                                        _POOL.transferFrom(loanInput.offer.lender, lien.lender, debt);
                                        unchecked {
                                            /* Send rest of sell funds from new lender to old borrower. */
                                            _POOL.transferFrom(
                                                loanInput.offer.lender,
                                                sellInput.offer.borrower,
                                                priceAfterFees - debt
                                            );
                                            /* Send rest of loan from new lender to new borrower. */
                                            _POOL.transferFrom(loanInput.offer.lender, msg.sender, loanAmount - priceAfterFees);
                                        }
                                    }
                                }
                                /**
                                 * @notice Purchases a locked NFT and uses the funds to repay the loan
                                 * @param lien Lien preimage
                                 * @param offer Sell offer
                                 * @param signature Lender offer signature
                                 */
                                function buyLocked(
                                    Lien calldata lien,
                                    SellOffer calldata offer,
                                    bytes calldata signature
                                ) public validateLien(lien, offer.lienId) lienIsActive(lien) {
                                    (uint256 priceAfterFees, uint256 debt) = _buyLocked(lien, offer, signature);
                                    /* Send token to buyer. */
                                    lien.collection.safeTransferFrom(address(this), msg.sender, lien.tokenId);
                                    /* Repay lender. */
                                    _POOL.transferFrom(msg.sender, lien.lender, debt);
                                    /* Send surplus to borrower. */
                                    unchecked {
                                        _POOL.transferFrom(msg.sender, lien.borrower, priceAfterFees - debt);
                                    }
                                }
                                /**
                                 * @notice Takes a bid on a locked NFT and use the funds to repay the lien
                                 * @dev Must be called by the borrower
                                 * @param lien Lien preimage
                                 * @param lienId Lien id
                                 * @param execution Marketplace execution data
                                 */
                                function takeBid(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    ExecutionV1 calldata execution
                                ) external validateLien(lien, lienId) lienIsActive(lien) {
                                    if (execution.makerOrder.order.trader == address(this) || msg.sender != lien.borrower) {
                                        revert Unauthorized();
                                    }
                                    /* Repay loan with funds received from the sale. */
                                    uint256 debt = _repay(lien, lienId);
                                    Helpers.executeTakeBid(
                                        lien,
                                        lienId,
                                        execution,
                                        debt,
                                        _POOL,
                                        _EXCHANGE,
                                        _DELEGATE,
                                        _BID_MATCHING_POLICY
                                    );
                                }
                                function takeBidV2(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    BidExecutionV2 calldata execution
                                ) external validateLien(lien, lienId) lienIsActive(lien) {
                                    if (msg.sender != lien.borrower) {
                                        revert Unauthorized();
                                    }
                                    /* Repay loan with funds received from the sale. */
                                    uint256 debt = _repay(lien, lienId);
                                    Helpers.executeTakeBidV2(lien, execution, debt, _POOL, _EXCHANGE_V2, _DELEGATE_V2);
                                }
                                /**
                                 * @notice Verify and take sell offer for token locked in lien; use the funds to repay the debt on the lien
                                 * @dev Does not transfer assets
                                 * @param lien Lien preimage
                                 * @param offer Loan offer
                                 * @param signature Loan offer signature
                                 * @return priceAfterFees Price of the token (after fees), debt Current debt amount
                                 */
                                function _buyLocked(
                                    Lien calldata lien,
                                    SellOffer calldata offer,
                                    bytes calldata signature
                                ) internal returns (uint256 priceAfterFees, uint256 debt) {
                                    if (lien.borrower != offer.borrower) {
                                        revert Unauthorized();
                                    }
                                    priceAfterFees = _takeSellOffer(offer, signature);
                                    /* Repay loan with funds received from the sale. */
                                    debt = _repay(lien, offer.lienId);
                                    if (priceAfterFees < debt) {
                                        revert InvalidRepayment();
                                    }
                                    emit BuyLocked(
                                        offer.lienId,
                                        address(lien.collection),
                                        msg.sender,
                                        lien.borrower,
                                        lien.tokenId
                                    );
                                }
                                /**
                                 * @notice Validates, fulfills, and transfers fees on sell offer
                                 * @param sellOffer Sell offer
                                 * @param sellSignature Sell offer signature
                                 */
                                function _takeSellOffer(
                                    SellOffer calldata sellOffer,
                                    bytes calldata sellSignature
                                ) internal returns (uint256 priceAfterFees) {
                                    _validateOffer(
                                        _hashSellOffer(sellOffer),
                                        sellOffer.borrower,
                                        sellOffer.oracle,
                                        sellSignature,
                                        sellOffer.expirationTime,
                                        sellOffer.salt
                                    );
                                    /* Mark the sell offer as fulfilled. */
                                    cancelledOrFulfilled[sellOffer.borrower][sellOffer.salt] = 1;
                                    /* Transfer fees. */
                                    uint256 totalFees = _transferFees(sellOffer.fees, msg.sender, sellOffer.price);
                                    unchecked {
                                        priceAfterFees = sellOffer.price - totalFees;
                                    }
                                }
                                function _transferFees(
                                    Fee[] calldata fees,
                                    address from,
                                    uint256 price
                                ) internal returns (uint256 totalFee) {
                                    uint256 feesLength = fees.length;
                                    for (uint256 i = 0; i < feesLength; ) {
                                        uint256 fee = (price * fees[i].rate) / _BASIS_POINTS;
                                        _POOL.transferFrom(from, fees[i].recipient, fee);
                                        totalFee += fee;
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                    if (totalFee > price) {
                                        revert FeesTooHigh();
                                    }
                                }
                                receive() external payable {
                                    if (msg.sender != address(_POOL) && msg.sender != address(_EXCHANGE_V2)) {
                                        revert Unauthorized();
                                    }
                                }
                                function onERC721Received(
                                    address operator,
                                    address from,
                                    uint256 tokenId,
                                    bytes calldata data
                                ) external pure returns (bytes4) {
                                    return this.onERC721Received.selector;
                                }
                                /*/////////////////////////////////////////////////////////////
                                                    PAYABLE WRAPPERS
                                /////////////////////////////////////////////////////////////*/
                                /**
                                 * @notice buyToBorrow wrapper that deposits ETH to pool
                                 */
                                function buyToBorrowETH(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    ExecutionV1 calldata execution
                                ) external payable returns (uint256 lienId) {
                                    _POOL.deposit{ value: msg.value }(msg.sender);
                                    return buyToBorrow(offer, signature, loanAmount, execution);
                                }
                                /**
                                 * @notice buyToBorrow wrapper that deposits ETH to pool
                                 */
                                function buyToBorrowV2ETH(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    AskExecutionV2 calldata execution
                                ) external payable returns (uint256 lienId) {
                                    _POOL.deposit{ value: msg.value }(msg.sender);
                                    return buyToBorrowV2(offer, signature, loanAmount, execution);
                                }
                                /**
                                 * @notice buyToBorrowLocked wrapper that deposits ETH to pool
                                 */
                                function buyToBorrowLockedETH(
                                    Lien calldata lien,
                                    SellInput calldata sellInput,
                                    LoanInput calldata loanInput,
                                    uint256 loanAmount
                                ) external payable returns (uint256 lienId) {
                                    _POOL.deposit{ value: msg.value }(msg.sender);
                                    return buyToBorrowLocked(lien, sellInput, loanInput, loanAmount);
                                }
                                /**
                                 * @notice buyLocked wrapper that deposits ETH to pool
                                 */
                                function buyLockedETH(
                                    Lien calldata lien,
                                    SellOffer calldata offer,
                                    bytes calldata signature
                                ) external payable {
                                    _POOL.deposit{ value: msg.value }(msg.sender);
                                    return buyLocked(lien, offer, signature);
                                }
                                /*/////////////////////////////////////////////////////////////
                                                    VALIDATION MODIFIERS
                                /////////////////////////////////////////////////////////////*/
                                modifier validateLien(Lien calldata lien, uint256 lienId) {
                                    if (!_validateLien(lien, lienId)) {
                                        revert InvalidLien();
                                    }
                                    _;
                                }
                                modifier lienIsActive(Lien calldata lien) {
                                    if (_lienIsDefaulted(lien)) {
                                        revert LienIsDefaulted();
                                    }
                                    _;
                                }
                                modifier auctionIsActive(Lien calldata lien) {
                                    if (!_auctionIsActive(lien)) {
                                        revert AuctionIsNotActive();
                                    }
                                    _;
                                }
                                function _validateLien(Lien calldata lien, uint256 lienId) internal view returns (bool) {
                                    return liens[lienId] == keccak256(abi.encode(lien));
                                }
                                function _lienIsDefaulted(Lien calldata lien) internal view returns (bool) {
                                    return
                                        lien.auctionStartBlock != 0 &&
                                        lien.auctionStartBlock + lien.auctionDuration < block.number;
                                }
                                function _auctionIsActive(Lien calldata lien) internal view returns (bool) {
                                    return
                                        lien.auctionStartBlock != 0 &&
                                        lien.auctionStartBlock + lien.auctionDuration >= block.number;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (proxy/utils/UUPSUpgradeable.sol)
                            pragma solidity ^0.8.0;
                            import "../../interfaces/draft-IERC1822Upgradeable.sol";
                            import "../ERC1967/ERC1967UpgradeUpgradeable.sol";
                            import "./Initializable.sol";
                            /**
                             * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
                             * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
                             *
                             * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
                             * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
                             * `UUPSUpgradeable` with a custom implementation of upgrades.
                             *
                             * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
                             *
                             * _Available since v4.1._
                             */
                            abstract contract UUPSUpgradeable is Initializable, IERC1822ProxiableUpgradeable, ERC1967UpgradeUpgradeable {
                                function __UUPSUpgradeable_init() internal onlyInitializing {
                                }
                                function __UUPSUpgradeable_init_unchained() internal onlyInitializing {
                                }
                                /// @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
                                address private immutable __self = address(this);
                                /**
                                 * @dev Check that the execution is being performed through a delegatecall call and that the execution context is
                                 * a proxy contract with an implementation (as defined in ERC1967) pointing to self. This should only be the case
                                 * for UUPS and transparent proxies that are using the current contract as their implementation. Execution of a
                                 * function through ERC1167 minimal proxies (clones) would not normally pass this test, but is not guaranteed to
                                 * fail.
                                 */
                                modifier onlyProxy() {
                                    require(address(this) != __self, "Function must be called through delegatecall");
                                    require(_getImplementation() == __self, "Function must be called through active proxy");
                                    _;
                                }
                                /**
                                 * @dev Check that the execution is not being performed through a delegate call. This allows a function to be
                                 * callable on the implementing contract but not through proxies.
                                 */
                                modifier notDelegated() {
                                    require(address(this) == __self, "UUPSUpgradeable: must not be called through delegatecall");
                                    _;
                                }
                                /**
                                 * @dev Implementation of the ERC1822 {proxiableUUID} function. This returns the storage slot used by the
                                 * implementation. It is used to validate the implementation's compatibility when performing an upgrade.
                                 *
                                 * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
                                 * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
                                 * function revert if invoked through a proxy. This is guaranteed by the `notDelegated` modifier.
                                 */
                                function proxiableUUID() external view virtual override notDelegated returns (bytes32) {
                                    return _IMPLEMENTATION_SLOT;
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy to `newImplementation`.
                                 *
                                 * Calls {_authorizeUpgrade}.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function upgradeTo(address newImplementation) external virtual onlyProxy {
                                    _authorizeUpgrade(newImplementation);
                                    _upgradeToAndCallUUPS(newImplementation, new bytes(0), false);
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
                                 * encoded in `data`.
                                 *
                                 * Calls {_authorizeUpgrade}.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual onlyProxy {
                                    _authorizeUpgrade(newImplementation);
                                    _upgradeToAndCallUUPS(newImplementation, data, true);
                                }
                                /**
                                 * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
                                 * {upgradeTo} and {upgradeToAndCall}.
                                 *
                                 * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
                                 *
                                 * ```solidity
                                 * function _authorizeUpgrade(address) internal override onlyOwner {}
                                 * ```
                                 */
                                function _authorizeUpgrade(address newImplementation) internal virtual;
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[50] private __gap;
                            }
                            // SPDX-License-Identifier: BSL 1.1 - Blend (c) Non Fungible Trading Ltd.
                            pragma solidity 0.8.17;
                            import "lib/solmate/src/utils/SignedWadMath.sol";
                            import { InvalidRepayment } from "./lib/Errors.sol";
                            import "./lib/Structs.sol";
                            import "../pool/interfaces/IBlurPool.sol";
                            import { IBlurExchangeV2 as IExchangeV2 } from "../exchangeV2/interfaces/IBlurExchangeV2.sol";
                            import { Order as OrderV1, SignatureVersion, Side } from "../exchangeV1/lib/OrderStructs.sol";
                            import {
                                TakeAskSingle,
                                TakeBidSingle,
                                FeeRate,
                                Taker,
                                Exchange,
                                Order as OrderV2,
                                AssetType
                            } from "../exchangeV2/lib/Structs.sol";
                            interface IExchange {
                                function execute(Input calldata sell, Input calldata buy) external payable;
                            }
                            library Helpers {
                                int256 private constant _YEAR_WAD = 365 days * 1e18;
                                uint256 private constant _LIQUIDATION_THRESHOLD = 100_000;
                                uint256 private constant _BASIS_POINTS = 10_000;
                                error InvalidExecution();
                                /**
                                 * @dev Computes the current debt of a borrow given the last time it was touched and the last computed debt.
                                 * @param amount Principal in ETH
                                 * @param startTime Start time of the loan
                                 * @param rate Interest rate (in bips)
                                 * @dev Formula: https://www.desmos.com/calculator/l6omp0rwnh
                                 */
                                function computeCurrentDebt(
                                    uint256 amount,
                                    uint256 rate,
                                    uint256 startTime
                                ) public view returns (uint256) {
                                    uint256 loanTime = block.timestamp - startTime;
                                    int256 yearsWad = wadDiv(int256(loanTime) * 1e18, _YEAR_WAD);
                                    return uint256(wadMul(int256(amount), wadExp(wadMul(yearsWad, bipsToSignedWads(rate)))));
                                }
                                /**
                                 * @dev Calculates the current maximum interest rate a specific refinancing
                                 * auction could settle at currently given the auction's start block and duration.
                                 * @param startBlock The block the auction started at
                                 * @param oldRate Previous interest rate (in bips)
                                 * @dev Formula: https://www.desmos.com/calculator/urasr71dhb
                                 */
                                function calcRefinancingAuctionRate(
                                    uint256 startBlock,
                                    uint256 auctionDuration,
                                    uint256 oldRate
                                ) public view returns (uint256) {
                                    uint256 currentAuctionBlock = block.number - startBlock;
                                    int256 oldRateWads = bipsToSignedWads(oldRate);
                                    uint256 auctionT1 = auctionDuration / 5;
                                    uint256 auctionT2 = (4 * auctionDuration) / 5;
                                    int256 maxRateWads;
                                    {
                                        int256 aInverse = -bipsToSignedWads(15000);
                                        int256 b = 2;
                                        int256 maxMinRateWads = bipsToSignedWads(500);
                                        if (oldRateWads < -((b * aInverse) / 2)) {
                                            maxRateWads = maxMinRateWads + (oldRateWads ** 2) / aInverse + b * oldRateWads;
                                        } else {
                                            maxRateWads = maxMinRateWads - ((b ** 2) * aInverse) / 4;
                                        }
                                    }
                                    int256 startSlope = maxRateWads / int256(auctionT1); // wad-bips per block
                                    int256 middleSlope = bipsToSignedWads(9000) / int256((3 * auctionDuration) / 5) + 1; // wad-bips per block (add one to account for rounding)
                                    int256 middleB = maxRateWads - int256(auctionT1) * middleSlope;
                                    if (currentAuctionBlock < auctionT1) {
                                        return signedWadsToBips(startSlope * int256(currentAuctionBlock));
                                    } else if (currentAuctionBlock < auctionT2) {
                                        return signedWadsToBips(middleSlope * int256(currentAuctionBlock) + middleB);
                                    } else if (currentAuctionBlock < auctionDuration) {
                                        int256 endSlope;
                                        int256 endB;
                                        {
                                            endSlope =
                                                (bipsToSignedWads(_LIQUIDATION_THRESHOLD) -
                                                    ((int256(auctionT2) * middleSlope) + middleB)) /
                                                int256(auctionDuration - auctionT2); // wad-bips per block
                                            endB =
                                                bipsToSignedWads(_LIQUIDATION_THRESHOLD) -
                                                int256(auctionDuration) *
                                                endSlope;
                                        }
                                        return signedWadsToBips(endSlope * int256(currentAuctionBlock) + endB);
                                    } else {
                                        return _LIQUIDATION_THRESHOLD;
                                    }
                                }
                                /**
                                 * @dev Converts an integer bips value to a signed wad value.
                                 */
                                function bipsToSignedWads(uint256 bips) public pure returns (int256) {
                                    return int256((bips * 1e18) / _BASIS_POINTS);
                                }
                                /**
                                 * @dev Converts a signed wad value to an integer bips value.
                                 */
                                function signedWadsToBips(int256 wads) public pure returns (uint256) {
                                    return uint256((wads * int256(_BASIS_POINTS)) / 1e18);
                                }
                                function executeTakeBid(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    ExecutionV1 calldata execution,
                                    uint256 debt,
                                    IBlurPool pool,
                                    IExchange exchange,
                                    address delegate,
                                    address matchingPolicy
                                ) external {
                                    /* Create sell side order from Blend. */
                                    OrderV1 memory sellOrder = OrderV1({
                                        trader: address(this),
                                        side: Side.Sell,
                                        matchingPolicy: matchingPolicy,
                                        collection: address(lien.collection),
                                        tokenId: lien.tokenId,
                                        amount: 1,
                                        paymentToken: address(pool),
                                        price: execution.makerOrder.order.price,
                                        listingTime: execution.makerOrder.order.listingTime + 1, // listingTime determines maker/taker
                                        expirationTime: type(uint256).max,
                                        fees: new Fee[](0),
                                        salt: lienId, // prevent reused order hash
                                        extraParams: "\\x01" // require oracle signature
                                    });
                                    Input memory sell = Input({
                                        order: sellOrder,
                                        v: 0,
                                        r: bytes32(0),
                                        s: bytes32(0),
                                        extraSignature: execution.extraSignature,
                                        signatureVersion: SignatureVersion.Single,
                                        blockNumber: execution.blockNumber
                                    });
                                    /* Execute marketplace order. */
                                    uint256 balanceBefore = pool.balanceOf(address(this));
                                    lien.collection.approve(delegate, lien.tokenId);
                                    exchange.execute(sell, execution.makerOrder);
                                    /* Determine the funds received from the sale (after fees). */
                                    uint256 amountReceivedFromSale = pool.balanceOf(address(this)) - balanceBefore;
                                    if (amountReceivedFromSale < debt) {
                                        revert InvalidRepayment();
                                    }
                                    /* Repay lender. */
                                    pool.transferFrom(address(this), lien.lender, debt);
                                    /* Send surplus to borrower. */
                                    unchecked {
                                        pool.transferFrom(address(this), lien.borrower, amountReceivedFromSale - debt);
                                    }
                                }
                                function executeTakeAskV2(
                                    LoanOffer calldata offer, 
                                    AskExecutionV2 calldata execution,
                                    uint256 loanAmount,
                                    uint256 collateralTokenId,
                                    uint256 price,
                                    IBlurPool pool,
                                    IExchangeV2 exchangeV2
                                ) external {
                                    OrderV2 calldata order = execution.order;
                                    if (address(offer.collection) != order.collection || order.assetType != AssetType.ERC721) {
                                        revert InvalidExecution();
                                    }
                                    /* Transfer funds. */
                                    /* Need to retrieve the ETH to fund the marketplace execution. */
                                    if (loanAmount < price) {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), loanAmount);
                                        /* Supplement difference from borrower. */
                                        unchecked {
                                            pool.withdrawFrom(msg.sender, address(this), price - loanAmount);
                                        }
                                    } else {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), price);
                                        /* Send surplus to borrower. */
                                        unchecked {
                                            pool.transferFrom(offer.lender, msg.sender, loanAmount - price);
                                        }
                                    }
                                    TakeAskSingle memory execute = TakeAskSingle({
                                        order: execution.order,
                                        exchange: Exchange({
                                            index: 0,
                                            proof: execution.proof,
                                            listing: Listing({
                                                index: execution.listing.index,
                                                tokenId: collateralTokenId,
                                                amount: 1,
                                                price: price
                                            }),
                                            taker: Taker({ tokenId: collateralTokenId, amount: 1 })
                                        }),
                                        takerFee: FeeRate(address(0), 0),
                                        signature: execution.signature,
                                        tokenRecipient: address(this)
                                    });
                                    exchangeV2.takeAskSingle{ value: price }(execute, execution.oracleSignature);
                                }
                                function executeTakeAsk(
                                    LoanOffer calldata offer,
                                    ExecutionV1 calldata execution,
                                    uint256 loanAmount,
                                    uint256 collateralTokenId,
                                    uint256 price,
                                    IBlurPool pool,
                                    IExchange exchange,
                                    address matchingPolicy
                                ) external {
                                    /* Transfer funds. */
                                    /* Need to retrieve the ETH to fund the marketplace execution. */
                                    if (loanAmount < price) {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), loanAmount);
                                        /* Supplement difference from borrower. */
                                        unchecked {
                                            pool.withdrawFrom(msg.sender, address(this), price - loanAmount);
                                        }
                                    } else {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), price);
                                        /* Send surplus to borrower. */
                                        unchecked {
                                            pool.transferFrom(offer.lender, msg.sender, loanAmount - price);
                                        }
                                    }
                                    OrderV1 memory buyOrder = OrderV1({
                                        trader: address(this),
                                        side: Side.Buy,
                                        matchingPolicy: matchingPolicy,
                                        collection: address(offer.collection),
                                        tokenId: collateralTokenId,
                                        amount: 1,
                                        paymentToken: address(0),
                                        price: price,
                                        listingTime: execution.makerOrder.order.listingTime + 1, // listingTime determines maker/taker
                                        expirationTime: type(uint256).max,
                                        fees: new Fee[](0),
                                        salt: uint160(execution.makerOrder.order.trader), // prevent reused order hash
                                        extraParams: "\\x01" // require oracle signature
                                    });
                                    Input memory buy = Input({
                                        order: buyOrder,
                                        v: 0,
                                        r: bytes32(0),
                                        s: bytes32(0),
                                        extraSignature: execution.extraSignature,
                                        signatureVersion: SignatureVersion.Single,
                                        blockNumber: execution.blockNumber
                                    });
                                    /* Execute order using ETH currently in contract. */
                                    exchange.execute{ value: price }(execution.makerOrder, buy);
                                }
                                function executeTakeBidV2(
                                    Lien calldata lien,
                                    BidExecutionV2 calldata execution,
                                    uint256 debt,
                                    IBlurPool pool,
                                    IExchangeV2 exchangeV2,
                                    address delegateV2
                                ) external {
                                    OrderV2 calldata order = execution.order;
                                    if (address(lien.collection) != order.collection || order.assetType != AssetType.ERC721) {
                                        revert InvalidExecution();
                                    }
                                    uint256 balanceBefore = pool.balanceOf(address(this));
                                    TakeBidSingle memory execute = TakeBidSingle({
                                        order: execution.order,
                                        exchange: Exchange({
                                            index: 0,
                                            proof: execution.proof,
                                            listing: execution.listing,
                                            taker: Taker({ tokenId: lien.tokenId, amount: 1 })
                                        }),
                                        takerFee: FeeRate(address(0), 0),
                                        signature: execution.signature
                                    });
                                    /* Execute marketplace order. */
                                    lien.collection.approve(delegateV2, lien.tokenId);
                                    exchangeV2.takeBidSingle(execute, execution.oracleSignature);
                                    /* Determine the funds received from the sale (after fees). */
                                    uint256 amountReceivedFromSale = pool.balanceOf(address(this)) - balanceBefore;
                                    if (amountReceivedFromSale < debt) {
                                        revert InvalidRepayment();
                                    }
                                    /* Repay lender. */
                                    pool.transferFrom(address(this), lien.lender, debt);
                                    /* Send surplus to borrower. */
                                    unchecked {
                                        pool.transferFrom(address(this), lien.borrower, amountReceivedFromSale - debt);
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            import "lib/solmate/src/tokens/ERC721.sol";
                            import { Input, Fee } from "../../exchangeV1/lib/OrderStructs.sol";
                            import { Order as OrderV2, Listing } from "../../exchangeV2/lib/Structs.sol";
                            struct LienPointer {
                                Lien lien;
                                uint256 lienId;
                            }
                            struct SellOffer {
                                address borrower;
                                uint256 lienId;
                                uint256 price;
                                uint256 expirationTime;
                                uint256 salt;
                                address oracle;
                                Fee[] fees;
                            }
                            struct Lien {
                                address lender;
                                address borrower;
                                ERC721 collection;
                                uint256 tokenId;
                                uint256 amount;
                                uint256 startTime;
                                uint256 rate;
                                uint256 auctionStartBlock;
                                uint256 auctionDuration;
                            }
                            struct LoanOffer {
                                address lender;
                                ERC721 collection;
                                uint256 totalAmount;
                                uint256 minAmount;
                                uint256 maxAmount;
                                uint256 auctionDuration;
                                uint256 salt;
                                uint256 expirationTime;
                                uint256 rate;
                                address oracle;
                            }
                            struct LoanInput {
                                LoanOffer offer;
                                bytes signature;
                            }
                            struct SellInput {
                                SellOffer offer;
                                bytes signature;
                            }
                            struct ExecutionV1 {
                                Input makerOrder;
                                bytes extraSignature;
                                uint256 blockNumber;
                            }
                            struct BidExecutionV2 {
                                OrderV2 order;
                                Listing listing;
                                bytes32[] proof;
                                bytes signature;
                                bytes oracleSignature;
                            }
                            struct AskExecutionV2 {
                                OrderV2 order;
                                Listing listing;
                                bytes32[] proof;
                                bytes signature;
                                bytes oracleSignature;
                            }
                            // SPDX-License-Identifier: BSL 1.1 - Blend (c) Non Fungible Trading Ltd.
                            pragma solidity 0.8.17;
                            import "lib/openzeppelin-contracts-upgradeable/contracts/access/Ownable2StepUpgradeable.sol";
                            import "./lib/Signatures.sol";
                            import "./interfaces/IOfferController.sol";
                            abstract contract OfferController is IOfferController, Signatures, Ownable2StepUpgradeable {
                                mapping(address => mapping(uint256 => uint256)) public cancelledOrFulfilled;
                                uint256[50] private _gap;
                                /**
                                 * @notice Assert offer validity
                                 * @param offerHash Offer hash
                                 * @param signer Address of offer signer
                                 * @param oracle Address of oracle
                                 * @param signature Packed signature array
                                 * @param expirationTime Offer expiration time
                                 * @param salt Offer salt
                                 */
                                function _validateOffer(
                                    bytes32 offerHash,
                                    address signer,
                                    address oracle,
                                    bytes calldata signature,
                                    uint256 expirationTime,
                                    uint256 salt
                                ) internal view {
                                    _verifyOfferAuthorization(offerHash, signer, oracle, signature);
                                    if (expirationTime < block.timestamp) {
                                        revert OfferExpired();
                                    }
                                    if (cancelledOrFulfilled[signer][salt] == 1) {
                                        revert OfferUnavailable();
                                    }
                                }
                                /*/////////////////////////////////////////
                                              CANCEL FUNCTIONS
                                /////////////////////////////////////////*/
                                /**
                                 * @notice Cancels offer salt for caller
                                 * @param salt Unique offer salt
                                 */
                                function cancelOffer(uint256 salt) external {
                                    _cancelOffer(msg.sender, salt);
                                }
                                /**
                                 * @notice Cancels offers in bulk for caller
                                 * @param salts List of offer salts
                                 */
                                function cancelOffers(uint256[] calldata salts) external {
                                    uint256 saltsLength = salts.length;
                                    for (uint256 i; i < saltsLength; ) {
                                        _cancelOffer(msg.sender, salts[i]);
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                }
                                /**
                                 * @notice Cancels all offers by incrementing caller nonce
                                 */
                                function incrementNonce() external {
                                    _incrementNonce(msg.sender);
                                }
                                /**
                                 * @notice Cancel offer by user and salt
                                 * @param user Address of user
                                 * @param salt Unique offer salt
                                 */
                                function _cancelOffer(address user, uint256 salt) private {
                                    cancelledOrFulfilled[user][salt] = 1;
                                    emit OfferCancelled(user, salt);
                                }
                                /**
                                 * @notice Cancel all orders by incrementing the user nonce
                                 * @param user Address of user
                                 */
                                function _incrementNonce(address user) internal {
                                    emit NonceIncremented(user, ++nonces[user]);
                                }
                                /*/////////////////////////////////////////
                                              ADMIN FUNCTIONS
                                /////////////////////////////////////////*/
                                /**
                                 * @notice Set approval for an oracle address
                                 * @param oracle Address of oracle
                                 * @param approved Whether the oracle is approved
                                 */
                                function setOracle(address oracle, bool approved) external onlyOwner {
                                    if (approved) {
                                        oracles[oracle] = 1;
                                    } else {
                                        oracles[oracle] = 0;
                                    }
                                }
                                /**
                                 * @notice Set the block range expiry of oracle signatures
                                 * @param _blockRange Block range
                                 */
                                function setBlockRange(uint256 _blockRange) external onlyOwner {
                                    blockRange = _blockRange;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "../lib/Structs.sol";
                            import "./IOfferController.sol";
                            interface IBlend is IOfferController {
                                event LoanOfferTaken(
                                    bytes32 offerHash,
                                    uint256 lienId,
                                    address collection,
                                    address lender,
                                    address borrower,
                                    uint256 loanAmount,
                                    uint256 rate,
                                    uint256 tokenId,
                                    uint256 auctionDuration
                                );
                                event Repay(uint256 lienId, address collection);
                                event StartAuction(uint256 lienId, address collection);
                                event Refinance(
                                    uint256 lienId,
                                    address collection,
                                    address newLender,
                                    uint256 newAmount,
                                    uint256 newRate,
                                    uint256 newAuctionDuration
                                );
                                event Seize(uint256 lienId, address collection);
                                event BuyLocked(
                                    uint256 lienId,
                                    address collection,
                                    address buyer,
                                    address seller,
                                    uint256 tokenId
                                );
                                function amountTaken(bytes32 offerHash) external view returns (uint256);
                                function liens(uint256 lienId) external view returns (bytes32);
                                /*//////////////////////////////////////////////////
                                                BORROW FLOWS
                                //////////////////////////////////////////////////*/
                                function borrow(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    uint256 collateralId
                                ) external returns (uint256 lienId);
                                function repay(Lien calldata lien, uint256 lienId) external;
                                /*//////////////////////////////////////////////////
                                                REFINANCING FLOWS
                                //////////////////////////////////////////////////*/
                                function startAuction(Lien calldata lien, uint256 lienId) external;
                                function seize(LienPointer[] calldata lienPointers) external;
                                function refinance(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    LoanOffer calldata offer,
                                    bytes calldata signature
                                ) external;
                                function refinanceAuction(Lien calldata lien, uint256 lienId, uint256 rate) external;
                                function refinanceAuctionByOther(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    LoanOffer calldata offer,
                                    bytes calldata signature
                                ) external;
                                function borrowerRefinance(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    uint256 loanAmount,
                                    LoanOffer calldata offer,
                                    bytes calldata signature
                                ) external;
                                /*//////////////////////////////////////////////////
                                                MARKETPLACE FLOWS
                                //////////////////////////////////////////////////*/
                                function buyToBorrow(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    ExecutionV1 calldata execution
                                ) external returns (uint256 lienId);
                                function buyToBorrowETH(
                                    LoanOffer calldata offer,
                                    bytes calldata signature,
                                    uint256 loanAmount,
                                    ExecutionV1 calldata execution
                                ) external payable returns (uint256 lienId);
                                function buyToBorrowLocked(
                                    Lien calldata lien,
                                    SellInput calldata sellInput,
                                    LoanInput calldata loanInput,
                                    uint256 loanAmount
                                ) external returns (uint256 lienId);
                                function buyToBorrowLockedETH(
                                    Lien calldata lien,
                                    SellInput calldata sellInput,
                                    LoanInput calldata loanInput,
                                    uint256 loanAmount
                                ) external payable returns (uint256 lienId);
                                function buyLocked(
                                    Lien calldata lien,
                                    SellOffer calldata offer,
                                    bytes calldata signature
                                ) external;
                                function buyLockedETH(
                                    Lien calldata lien,
                                    SellOffer calldata offer,
                                    bytes calldata signature
                                ) external payable;
                                function takeBid(Lien calldata lien, uint256 lienId, ExecutionV1 calldata execution) external;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            interface IBlurPool {
                                event Transfer(address indexed from, address indexed to, uint256 amount);
                                function initialize() external;
                                function decimals() external pure returns (uint8);
                                function totalSupply() external view returns (uint256);
                                function balanceOf(address user) external view returns (uint256);
                                function deposit() external payable;
                                function deposit(address user) external payable;
                                function withdraw(uint256 amount) external;
                                function withdrawFrom(address from, address to, uint256 amount) external;
                                function transferFrom(address from, address to, uint256 amount) external returns (bool);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
                             * proxy whose upgrades are fully controlled by the current implementation.
                             */
                            interface IERC1822ProxiableUpgradeable {
                                /**
                                 * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
                                 * address.
                                 *
                                 * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
                                 * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
                                 * function revert if invoked through a proxy.
                                 */
                                function proxiableUUID() external view returns (bytes32);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.3) (proxy/ERC1967/ERC1967Upgrade.sol)
                            pragma solidity ^0.8.2;
                            import "../beacon/IBeaconUpgradeable.sol";
                            import "../../interfaces/IERC1967Upgradeable.sol";
                            import "../../interfaces/draft-IERC1822Upgradeable.sol";
                            import "../../utils/AddressUpgradeable.sol";
                            import "../../utils/StorageSlotUpgradeable.sol";
                            import "../utils/Initializable.sol";
                            /**
                             * @dev This abstract contract provides getters and event emitting update functions for
                             * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
                             *
                             * _Available since v4.1._
                             *
                             * @custom:oz-upgrades-unsafe-allow delegatecall
                             */
                            abstract contract ERC1967UpgradeUpgradeable is Initializable, IERC1967Upgradeable {
                                function __ERC1967Upgrade_init() internal onlyInitializing {
                                }
                                function __ERC1967Upgrade_init_unchained() internal onlyInitializing {
                                }
                                // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
                                bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
                                /**
                                 * @dev Storage slot with the address of the current implementation.
                                 * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                                /**
                                 * @dev Returns the current implementation address.
                                 */
                                function _getImplementation() internal view returns (address) {
                                    return StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new address in the EIP1967 implementation slot.
                                 */
                                function _setImplementation(address newImplementation) private {
                                    require(AddressUpgradeable.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                                    StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                                }
                                /**
                                 * @dev Perform implementation upgrade
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeTo(address newImplementation) internal {
                                    _setImplementation(newImplementation);
                                    emit Upgraded(newImplementation);
                                }
                                /**
                                 * @dev Perform implementation upgrade with additional setup call.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeToAndCall(
                                    address newImplementation,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    _upgradeTo(newImplementation);
                                    if (data.length > 0 || forceCall) {
                                        _functionDelegateCall(newImplementation, data);
                                    }
                                }
                                /**
                                 * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeToAndCallUUPS(
                                    address newImplementation,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    // Upgrades from old implementations will perform a rollback test. This test requires the new
                                    // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                                    // this special case will break upgrade paths from old UUPS implementation to new ones.
                                    if (StorageSlotUpgradeable.getBooleanSlot(_ROLLBACK_SLOT).value) {
                                        _setImplementation(newImplementation);
                                    } else {
                                        try IERC1822ProxiableUpgradeable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                                            require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                                        } catch {
                                            revert("ERC1967Upgrade: new implementation is not UUPS");
                                        }
                                        _upgradeToAndCall(newImplementation, data, forceCall);
                                    }
                                }
                                /**
                                 * @dev Storage slot with the admin of the contract.
                                 * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                                /**
                                 * @dev Returns the current admin.
                                 */
                                function _getAdmin() internal view returns (address) {
                                    return StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new address in the EIP1967 admin slot.
                                 */
                                function _setAdmin(address newAdmin) private {
                                    require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                                    StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
                                }
                                /**
                                 * @dev Changes the admin of the proxy.
                                 *
                                 * Emits an {AdminChanged} event.
                                 */
                                function _changeAdmin(address newAdmin) internal {
                                    emit AdminChanged(_getAdmin(), newAdmin);
                                    _setAdmin(newAdmin);
                                }
                                /**
                                 * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
                                 * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
                                 */
                                bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
                                /**
                                 * @dev Returns the current beacon.
                                 */
                                function _getBeacon() internal view returns (address) {
                                    return StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new beacon in the EIP1967 beacon slot.
                                 */
                                function _setBeacon(address newBeacon) private {
                                    require(AddressUpgradeable.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                                    require(
                                        AddressUpgradeable.isContract(IBeaconUpgradeable(newBeacon).implementation()),
                                        "ERC1967: beacon implementation is not a contract"
                                    );
                                    StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value = newBeacon;
                                }
                                /**
                                 * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
                                 * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
                                 *
                                 * Emits a {BeaconUpgraded} event.
                                 */
                                function _upgradeBeaconToAndCall(
                                    address newBeacon,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    _setBeacon(newBeacon);
                                    emit BeaconUpgraded(newBeacon);
                                    if (data.length > 0 || forceCall) {
                                        _functionDelegateCall(IBeaconUpgradeable(newBeacon).implementation(), data);
                                    }
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                                 * but performing a delegate call.
                                 *
                                 * _Available since v3.4._
                                 */
                                function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
                                    require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, bytes memory returndata) = target.delegatecall(data);
                                    return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
                                }
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[50] private __gap;
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.1) (proxy/utils/Initializable.sol)
                            pragma solidity ^0.8.2;
                            import "../../utils/AddressUpgradeable.sol";
                            /**
                             * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                             * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                             * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                             * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                             *
                             * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                             * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                             * case an upgrade adds a module that needs to be initialized.
                             *
                             * For example:
                             *
                             * [.hljs-theme-light.nopadding]
                             * ```
                             * contract MyToken is ERC20Upgradeable {
                             *     function initialize() initializer public {
                             *         __ERC20_init("MyToken", "MTK");
                             *     }
                             * }
                             * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                             *     function initializeV2() reinitializer(2) public {
                             *         __ERC20Permit_init("MyToken");
                             *     }
                             * }
                             * ```
                             *
                             * 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 prevent the implementation contract from being used, you should invoke
                             * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                             *
                             * [.hljs-theme-light.nopadding]
                             * ```
                             * /// @custom:oz-upgrades-unsafe-allow constructor
                             * constructor() {
                             *     _disableInitializers();
                             * }
                             * ```
                             * ====
                             */
                            abstract contract Initializable {
                                /**
                                 * @dev Indicates that the contract has been initialized.
                                 * @custom:oz-retyped-from bool
                                 */
                                uint8 private _initialized;
                                /**
                                 * @dev Indicates that the contract is in the process of being initialized.
                                 */
                                bool private _initializing;
                                /**
                                 * @dev Triggered when the contract has been initialized or reinitialized.
                                 */
                                event Initialized(uint8 version);
                                /**
                                 * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                                 * `onlyInitializing` functions can be used to initialize parent contracts.
                                 *
                                 * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
                                 * constructor.
                                 *
                                 * Emits an {Initialized} event.
                                 */
                                modifier initializer() {
                                    bool isTopLevelCall = !_initializing;
                                    require(
                                        (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                                        "Initializable: contract is already initialized"
                                    );
                                    _initialized = 1;
                                    if (isTopLevelCall) {
                                        _initializing = true;
                                    }
                                    _;
                                    if (isTopLevelCall) {
                                        _initializing = false;
                                        emit Initialized(1);
                                    }
                                }
                                /**
                                 * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                                 * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                                 * used to initialize parent contracts.
                                 *
                                 * A reinitializer may be used after the original initialization step. This is essential to configure modules that
                                 * are added through upgrades and that require initialization.
                                 *
                                 * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
                                 * cannot be nested. If one is invoked in the context of another, execution will revert.
                                 *
                                 * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                                 * a contract, executing them in the right order is up to the developer or operator.
                                 *
                                 * WARNING: setting the version to 255 will prevent any future reinitialization.
                                 *
                                 * Emits an {Initialized} event.
                                 */
                                modifier reinitializer(uint8 version) {
                                    require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                                    _initialized = version;
                                    _initializing = true;
                                    _;
                                    _initializing = false;
                                    emit Initialized(version);
                                }
                                /**
                                 * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                                 * {initializer} and {reinitializer} modifiers, directly or indirectly.
                                 */
                                modifier onlyInitializing() {
                                    require(_initializing, "Initializable: contract is not initializing");
                                    _;
                                }
                                /**
                                 * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                                 * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                                 * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                                 * through proxies.
                                 *
                                 * Emits an {Initialized} event the first time it is successfully executed.
                                 */
                                function _disableInitializers() internal virtual {
                                    require(!_initializing, "Initializable: contract is initializing");
                                    if (_initialized < type(uint8).max) {
                                        _initialized = type(uint8).max;
                                        emit Initialized(type(uint8).max);
                                    }
                                }
                                /**
                                 * @dev Returns the highest version that has been initialized. See {reinitializer}.
                                 */
                                function _getInitializedVersion() internal view returns (uint8) {
                                    return _initialized;
                                }
                                /**
                                 * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
                                 */
                                function _isInitializing() internal view returns (bool) {
                                    return _initializing;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev This is the interface that {BeaconProxy} expects of its beacon.
                             */
                            interface IBeaconUpgradeable {
                                /**
                                 * @dev Must return an address that can be used as a delegate call target.
                                 *
                                 * {BeaconProxy} will check that this address is a contract.
                                 */
                                function implementation() external view returns (address);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.3) (interfaces/IERC1967.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev ERC-1967: Proxy Storage Slots. This interface contains the events defined in the ERC.
                             *
                             * _Available since v4.9._
                             */
                            interface IERC1967Upgradeable {
                                /**
                                 * @dev Emitted when the implementation is upgraded.
                                 */
                                event Upgraded(address indexed implementation);
                                /**
                                 * @dev Emitted when the admin account has changed.
                                 */
                                event AdminChanged(address previousAdmin, address newAdmin);
                                /**
                                 * @dev Emitted when the beacon is changed.
                                 */
                                event BeaconUpgraded(address indexed beacon);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
                            pragma solidity ^0.8.1;
                            /**
                             * @dev Collection of functions related to the address type
                             */
                            library AddressUpgradeable {
                                /**
                                 * @dev Returns true if `account` is a contract.
                                 *
                                 * [IMPORTANT]
                                 * ====
                                 * It is unsafe to assume that an address for which this function returns
                                 * false is an externally-owned account (EOA) and not a contract.
                                 *
                                 * Among others, `isContract` will return false for the following
                                 * types of addresses:
                                 *
                                 *  - an externally-owned account
                                 *  - a contract in construction
                                 *  - an address where a contract will be created
                                 *  - an address where a contract lived, but was destroyed
                                 * ====
                                 *
                                 * [IMPORTANT]
                                 * ====
                                 * You shouldn't rely on `isContract` to protect against flash loan attacks!
                                 *
                                 * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                                 * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                                 * constructor.
                                 * ====
                                 */
                                function isContract(address account) internal view returns (bool) {
                                    // This method relies on extcodesize/address.code.length, which returns 0
                                    // for contracts in construction, since the code is only stored at the end
                                    // of the constructor execution.
                                    return account.code.length > 0;
                                }
                                /**
                                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                                 * `recipient`, forwarding all available gas and reverting on errors.
                                 *
                                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                                 * imposed by `transfer`, making them unable to receive funds via
                                 * `transfer`. {sendValue} removes this limitation.
                                 *
                                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                                 *
                                 * IMPORTANT: because control is transferred to `recipient`, care must be
                                 * taken to not create reentrancy vulnerabilities. Consider using
                                 * {ReentrancyGuard} or the
                                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                                 */
                                function sendValue(address payable recipient, uint256 amount) internal {
                                    require(address(this).balance >= amount, "Address: insufficient balance");
                                    (bool success, ) = recipient.call{value: amount}("");
                                    require(success, "Address: unable to send value, recipient may have reverted");
                                }
                                /**
                                 * @dev Performs a Solidity function call using a low level `call`. A
                                 * plain `call` is an unsafe replacement for a function call: use this
                                 * function instead.
                                 *
                                 * If `target` reverts with a revert reason, it is bubbled up by this
                                 * function (like regular Solidity function calls).
                                 *
                                 * Returns the raw returned data. To convert to the expected return value,
                                 * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                                 *
                                 * Requirements:
                                 *
                                 * - `target` must be a contract.
                                 * - calling `target` with `data` must not revert.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, 0, "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");
                                    (bool success, bytes memory returndata) = target.call{value: value}(data);
                                    return verifyCallResultFromTarget(target, 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) {
                                    (bool success, bytes memory returndata) = target.staticcall(data);
                                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                                }
                                /**
                                 * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
                                 * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
                                 *
                                 * _Available since v4.8._
                                 */
                                function verifyCallResultFromTarget(
                                    address target,
                                    bool success,
                                    bytes memory returndata,
                                    string memory errorMessage
                                ) internal view returns (bytes memory) {
                                    if (success) {
                                        if (returndata.length == 0) {
                                            // only check isContract if the call was successful and the return data is empty
                                            // otherwise we already know that it was a contract
                                            require(isContract(target), "Address: call to non-contract");
                                        }
                                        return returndata;
                                    } else {
                                        _revert(returndata, errorMessage);
                                    }
                                }
                                /**
                                 * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
                                 * revert reason or 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 {
                                        _revert(returndata, errorMessage);
                                    }
                                }
                                function _revert(bytes memory returndata, string memory errorMessage) private pure {
                                    // Look for revert reason and bubble it up if present
                                    if (returndata.length > 0) {
                                        // The easiest way to bubble the revert reason is using memory via assembly
                                        /// @solidity memory-safe-assembly
                                        assembly {
                                            let returndata_size := mload(returndata)
                                            revert(add(32, returndata), returndata_size)
                                        }
                                    } else {
                                        revert(errorMessage);
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev Library for reading and writing primitive types to specific storage slots.
                             *
                             * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
                             * This library helps with reading and writing to such slots without the need for inline assembly.
                             *
                             * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
                             *
                             * Example usage to set ERC1967 implementation slot:
                             * ```
                             * contract ERC1967 {
                             *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                             *
                             *     function _getImplementation() internal view returns (address) {
                             *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                             *     }
                             *
                             *     function _setImplementation(address newImplementation) internal {
                             *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                             *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                             *     }
                             * }
                             * ```
                             *
                             * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
                             */
                            library StorageSlotUpgradeable {
                                struct AddressSlot {
                                    address value;
                                }
                                struct BooleanSlot {
                                    bool value;
                                }
                                struct Bytes32Slot {
                                    bytes32 value;
                                }
                                struct Uint256Slot {
                                    uint256 value;
                                }
                                /**
                                 * @dev Returns an `AddressSlot` with member `value` located at `slot`.
                                 */
                                function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
                                 */
                                function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
                                 */
                                function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
                                 */
                                function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.8.0;
                            /// @notice Signed 18 decimal fixed point (wad) arithmetic library.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SignedWadMath.sol)
                            /// @author Modified from Remco Bloemen (https://xn--2-umb.com/22/exp-ln/index.html)
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            function toWadUnsafe(uint256 x) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 1e18.
                                    r := mul(x, 1000000000000000000)
                                }
                            }
                            /// @dev Takes an integer amount of seconds and converts it to a wad amount of days.
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            /// @dev Not meant for negative second amounts, it assumes x is positive.
                            function toDaysWadUnsafe(uint256 x) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 1e18 and then divide it by 86400.
                                    r := div(mul(x, 1000000000000000000), 86400)
                                }
                            }
                            /// @dev Takes a wad amount of days and converts it to an integer amount of seconds.
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            /// @dev Not meant for negative day amounts, it assumes x is positive.
                            function fromDaysWadUnsafe(int256 x) pure returns (uint256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 86400 and then divide it by 1e18.
                                    r := div(mul(x, 86400), 1000000000000000000)
                                }
                            }
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            function unsafeWadMul(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by y and divide by 1e18.
                                    r := sdiv(mul(x, y), 1000000000000000000)
                                }
                            }
                            /// @dev Will return 0 instead of reverting if y is zero and will
                            /// not revert on overflow, only use where overflow is not possible.
                            function unsafeWadDiv(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 1e18 and divide it by y.
                                    r := sdiv(mul(x, 1000000000000000000), y)
                                }
                            }
                            function wadMul(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Store x * y in r for now.
                                    r := mul(x, y)
                                    // Equivalent to require(x == 0 || (x * y) / x == y)
                                    if iszero(or(iszero(x), eq(sdiv(r, x), y))) {
                                        revert(0, 0)
                                    }
                                    // Scale the result down by 1e18.
                                    r := sdiv(r, 1000000000000000000)
                                }
                            }
                            function wadDiv(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Store x * 1e18 in r for now.
                                    r := mul(x, 1000000000000000000)
                                    // Equivalent to require(y != 0 && ((x * 1e18) / 1e18 == x))
                                    if iszero(and(iszero(iszero(y)), eq(sdiv(r, 1000000000000000000), x))) {
                                        revert(0, 0)
                                    }
                                    // Divide r by y.
                                    r := sdiv(r, y)
                                }
                            }
                            /// @dev Will not work with negative bases, only use when x is positive.
                            function wadPow(int256 x, int256 y) pure returns (int256) {
                                // Equivalent to x to the power of y because x ** y = (e ** ln(x)) ** y = e ** (ln(x) * y)
                                return wadExp((wadLn(x) * y) / 1e18); // Using ln(x) means x must be greater than 0.
                            }
                            function wadExp(int256 x) pure returns (int256 r) {
                                unchecked {
                                    // When the result is < 0.5 we return zero. This happens when
                                    // x <= floor(log(0.5e18) * 1e18) ~ -42e18
                                    if (x <= -42139678854452767551) return 0;
                                    // When the result is > (2**255 - 1) / 1e18 we can not represent it as an
                                    // int. This happens when x >= floor(log((2**255 - 1) / 1e18) * 1e18) ~ 135.
                                    if (x >= 135305999368893231589) revert("EXP_OVERFLOW");
                                    // x is now in the range (-42, 136) * 1e18. Convert to (-42, 136) * 2**96
                                    // for more intermediate precision and a binary basis. This base conversion
                                    // is a multiplication by 1e18 / 2**96 = 5**18 / 2**78.
                                    x = (x << 78) / 5**18;
                                    // Reduce range of x to (-½ ln 2, ½ ln 2) * 2**96 by factoring out powers
                                    // of two such that exp(x) = exp(x') * 2**k, where k is an integer.
                                    // Solving this gives k = round(x / log(2)) and x' = x - k * log(2).
                                    int256 k = ((x << 96) / 54916777467707473351141471128 + 2**95) >> 96;
                                    x = x - k * 54916777467707473351141471128;
                                    // k is in the range [-61, 195].
                                    // Evaluate using a (6, 7)-term rational approximation.
                                    // p is made monic, we'll multiply by a scale factor later.
                                    int256 y = x + 1346386616545796478920950773328;
                                    y = ((y * x) >> 96) + 57155421227552351082224309758442;
                                    int256 p = y + x - 94201549194550492254356042504812;
                                    p = ((p * y) >> 96) + 28719021644029726153956944680412240;
                                    p = p * x + (4385272521454847904659076985693276 << 96);
                                    // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                    int256 q = x - 2855989394907223263936484059900;
                                    q = ((q * x) >> 96) + 50020603652535783019961831881945;
                                    q = ((q * x) >> 96) - 533845033583426703283633433725380;
                                    q = ((q * x) >> 96) + 3604857256930695427073651918091429;
                                    q = ((q * x) >> 96) - 14423608567350463180887372962807573;
                                    q = ((q * x) >> 96) + 26449188498355588339934803723976023;
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        // Div in assembly because solidity adds a zero check despite the unchecked.
                                        // The q polynomial won't have zeros in the domain as all its roots are complex.
                                        // No scaling is necessary because p is already 2**96 too large.
                                        r := sdiv(p, q)
                                    }
                                    // r should be in the range (0.09, 0.25) * 2**96.
                                    // We now need to multiply r by:
                                    // * the scale factor s = ~6.031367120.
                                    // * the 2**k factor from the range reduction.
                                    // * the 1e18 / 2**96 factor for base conversion.
                                    // We do this all at once, with an intermediate result in 2**213
                                    // basis, so the final right shift is always by a positive amount.
                                    r = int256((uint256(r) * 3822833074963236453042738258902158003155416615667) >> uint256(195 - k));
                                }
                            }
                            function wadLn(int256 x) pure returns (int256 r) {
                                unchecked {
                                    require(x > 0, "UNDEFINED");
                                    // We want to convert x from 10**18 fixed point to 2**96 fixed point.
                                    // We do this by multiplying by 2**96 / 10**18. But since
                                    // ln(x * C) = ln(x) + ln(C), we can simply do nothing here
                                    // and add ln(2**96 / 10**18) at the end.
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
                                        r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
                                        r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
                                        r := or(r, shl(4, lt(0xffff, shr(r, x))))
                                        r := or(r, shl(3, lt(0xff, shr(r, x))))
                                        r := or(r, shl(2, lt(0xf, shr(r, x))))
                                        r := or(r, shl(1, lt(0x3, shr(r, x))))
                                        r := or(r, lt(0x1, shr(r, x)))
                                    }
                                    // Reduce range of x to (1, 2) * 2**96
                                    // ln(2^k * x) = k * ln(2) + ln(x)
                                    int256 k = r - 96;
                                    x <<= uint256(159 - k);
                                    x = int256(uint256(x) >> 159);
                                    // Evaluate using a (8, 8)-term rational approximation.
                                    // p is made monic, we will multiply by a scale factor later.
                                    int256 p = x + 3273285459638523848632254066296;
                                    p = ((p * x) >> 96) + 24828157081833163892658089445524;
                                    p = ((p * x) >> 96) + 43456485725739037958740375743393;
                                    p = ((p * x) >> 96) - 11111509109440967052023855526967;
                                    p = ((p * x) >> 96) - 45023709667254063763336534515857;
                                    p = ((p * x) >> 96) - 14706773417378608786704636184526;
                                    p = p * x - (795164235651350426258249787498 << 96);
                                    // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                    // q is monic by convention.
                                    int256 q = x + 5573035233440673466300451813936;
                                    q = ((q * x) >> 96) + 71694874799317883764090561454958;
                                    q = ((q * x) >> 96) + 283447036172924575727196451306956;
                                    q = ((q * x) >> 96) + 401686690394027663651624208769553;
                                    q = ((q * x) >> 96) + 204048457590392012362485061816622;
                                    q = ((q * x) >> 96) + 31853899698501571402653359427138;
                                    q = ((q * x) >> 96) + 909429971244387300277376558375;
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        // Div in assembly because solidity adds a zero check despite the unchecked.
                                        // The q polynomial is known not to have zeros in the domain.
                                        // No scaling required because p is already 2**96 too large.
                                        r := sdiv(p, q)
                                    }
                                    // r is in the range (0, 0.125) * 2**96
                                    // Finalization, we need to:
                                    // * multiply by the scale factor s = 5.549…
                                    // * add ln(2**96 / 10**18)
                                    // * add k * ln(2)
                                    // * multiply by 10**18 / 2**96 = 5**18 >> 78
                                    // mul s * 5e18 * 2**96, base is now 5**18 * 2**192
                                    r *= 1677202110996718588342820967067443963516166;
                                    // add ln(2) * k * 5e18 * 2**192
                                    r += 16597577552685614221487285958193947469193820559219878177908093499208371 * k;
                                    // add ln(2**96 / 10**18) * 5e18 * 2**192
                                    r += 600920179829731861736702779321621459595472258049074101567377883020018308;
                                    // base conversion: mul 2**18 / 2**192
                                    r >>= 174;
                                }
                            }
                            /// @dev Will return 0 instead of reverting if y is zero.
                            function unsafeDiv(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Divide x by y.
                                    r := sdiv(x, y)
                                }
                            }
                            // SPDX-License-Identifier: BSL 1.1 - Blend (c) Non Fungible Trading Ltd.
                            pragma solidity 0.8.17;
                            // Blend
                            error Unauthorized();
                            error InvalidLoan();
                            error InvalidLien();
                            error InsufficientOffer();
                            error InvalidRepayment();
                            error LienIsDefaulted();
                            error LienNotDefaulted();
                            error AuctionIsActive();
                            error AuctionIsNotActive();
                            error InvalidRefinance();
                            error RateTooHigh();
                            error FeesTooHigh();
                            error CollectionsDoNotMatch();
                            error InvalidAuctionDuration();
                            // OfferController
                            error OfferExpired();
                            error OfferUnavailable();
                            // Signatures
                            error UnauthorizedOracle();
                            error SignatureExpired();
                            error InvalidSignature();
                            error InvalidVParameter();
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            import {
                                TakeAsk,
                                TakeBid,
                                TakeAskSingle,
                                TakeBidSingle,
                                Order,
                                Exchange,
                                Fees,
                                FeeRate,
                                AssetType,
                                OrderType,
                                Transfer,
                                FungibleTransfers,
                                StateUpdate,
                                Cancel,
                                Listing
                            } from "../lib/Structs.sol";
                            interface IBlurExchangeV2 {
                                error InsufficientFunds();
                                error TokenTransferFailed();
                                error InvalidOrder();
                                error ProtocolFeeTooHigh();
                                event NewProtocolFee(address indexed recipient, uint16 indexed rate);
                                event NewGovernor(address indexed governor);
                                event NewBlockRange(uint256 blockRange);
                                event CancelTrade(address indexed user, bytes32 hash, uint256 index, uint256 amount);
                                event NonceIncremented(address indexed user, uint256 newNonce);
                                event SetOracle(address indexed user, bool approved);
                                function initialize() external;
                                function setProtocolFee(address recipient, uint16 rate) external;
                                function setGovernor(address _governor) external;
                                function setOracle(address oracle, bool approved) external;
                                function setBlockRange(uint256 _blockRange) external;
                                function cancelTrades(Cancel[] memory cancels) external;
                                function incrementNonce() external;
                                /*//////////////////////////////////////////////////////////////
                                                      EXECUTION WRAPPERS
                                //////////////////////////////////////////////////////////////*/
                                function takeAsk(TakeAsk memory inputs, bytes calldata oracleSignature) external payable;
                                function takeBid(TakeBid memory inputs, bytes calldata oracleSignature) external;
                                function takeAskSingle(TakeAskSingle memory inputs, bytes calldata oracleSignature) external payable;
                                function takeBidSingle(TakeBidSingle memory inputs, bytes calldata oracleSignature) external;
                                /*//////////////////////////////////////////////////////////////
                                                    EXECUTION POOL WRAPPERS
                                //////////////////////////////////////////////////////////////*/
                                function takeAskSinglePool(
                                    TakeAskSingle memory inputs,
                                    bytes calldata oracleSignature,
                                    uint256 amountToWithdraw
                                ) external payable;
                                function takeAskPool(
                                    TakeAsk memory inputs,
                                    bytes calldata oracleSignature,
                                    uint256 amountToWithdraw
                                ) external payable;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            enum Side { Buy, Sell }
                            enum SignatureVersion { Single, Bulk }
                            enum AssetType { ERC721, ERC1155 }
                            struct Fee {
                                uint16 rate;
                                address payable recipient;
                            }
                            struct Order {
                                address trader;
                                Side side;
                                address matchingPolicy;
                                address collection;
                                uint256 tokenId;
                                uint256 amount;
                                address paymentToken;
                                uint256 price;
                                uint256 listingTime;
                                /* Order expiration timestamp - 0 for oracle cancellations. */
                                uint256 expirationTime;
                                Fee[] fees;
                                uint256 salt;
                                bytes extraParams;
                            }
                            struct Input {
                                Order order;
                                uint8 v;
                                bytes32 r;
                                bytes32 s;
                                bytes extraSignature;
                                SignatureVersion signatureVersion;
                                uint256 blockNumber;
                            }
                            struct Execution {
                              Input sell;
                              Input buy;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.17;
                            struct TakeAsk {
                                Order[] orders;
                                Exchange[] exchanges;
                                FeeRate takerFee;
                                bytes signatures;
                                address tokenRecipient;
                            }
                            struct TakeAskSingle {
                                Order order;
                                Exchange exchange;
                                FeeRate takerFee;
                                bytes signature;
                                address tokenRecipient;
                            }
                            struct TakeBid {
                                Order[] orders;
                                Exchange[] exchanges;
                                FeeRate takerFee;
                                bytes signatures;
                            }
                            struct TakeBidSingle {
                                Order order;
                                Exchange exchange;
                                FeeRate takerFee;
                                bytes signature;
                            }
                            enum AssetType {
                                ERC721,
                                ERC1155
                            }
                            enum OrderType {
                                ASK,
                                BID
                            }
                            struct Exchange { // Size: 0x80
                                uint256 index; // 0x00
                                bytes32[] proof; // 0x20
                                Listing listing; // 0x40
                                Taker taker; // 0x60
                            }
                            struct Listing { // Size: 0x80
                                uint256 index; // 0x00
                                uint256 tokenId; // 0x20
                                uint256 amount; // 0x40
                                uint256 price; // 0x60
                            }
                            struct Taker { // Size: 0x40
                                uint256 tokenId; // 0x00
                                uint256 amount; // 0x20
                            }
                            struct Order { // Size: 0x100
                                address trader; // 0x00
                                address collection; // 0x20
                                bytes32 listingsRoot; // 0x40
                                uint256 numberOfListings; // 0x60
                                uint256 expirationTime; // 0x80
                                AssetType assetType; // 0xa0
                                FeeRate makerFee; // 0xc0
                                uint256 salt; // 0xe0
                            }
                            /*
                            Reference only; struct is composed manually using calldata formatting in execution
                            struct ExecutionBatch { // Size: 0x80
                                address taker; // 0x00
                                OrderType orderType; // 0x20
                                Transfer[] transfers; // 0x40
                                uint256 length; // 0x60
                            }
                            */
                            struct Transfer { // Size: 0xa0
                                address trader; // 0x00
                                uint256 id; // 0x20
                                uint256 amount; // 0x40
                                address collection; // 0x60
                                AssetType assetType; // 0x80
                            }
                            struct FungibleTransfers {
                                uint256 totalProtocolFee;
                                uint256 totalSellerTransfer;
                                uint256 totalTakerFee;
                                uint256 feeRecipientId;
                                uint256 makerId;
                                address[] feeRecipients;
                                address[] makers;
                                uint256[] makerTransfers;
                                uint256[] feeTransfers;
                                AtomicExecution[] executions;
                            }
                            struct AtomicExecution { // Size: 0xe0
                                uint256 makerId; // 0x00
                                uint256 sellerAmount; // 0x20
                                uint256 makerFeeRecipientId; // 0x40
                                uint256 makerFeeAmount; // 0x60
                                uint256 takerFeeAmount; // 0x80
                                uint256 protocolFeeAmount; // 0xa0
                                StateUpdate stateUpdate; // 0xc0
                            }
                            struct StateUpdate { // Size: 0xa0
                                address trader; // 0x00
                                bytes32 hash; // 0x20
                                uint256 index; // 0x40
                                uint256 value; // 0x60
                                uint256 maxAmount; // 0x80
                            }
                            struct Fees { // Size: 0x40
                                FeeRate protocolFee; // 0x00
                                FeeRate takerFee; // 0x20
                            }
                            struct FeeRate { // Size: 0x40
                                address recipient; // 0x00
                                uint16 rate; // 0x20
                            }
                            struct Cancel {
                                bytes32 hash;
                                uint256 index;
                                uint256 amount;
                            }
                            // SPDX-License-Identifier: AGPL-3.0-only
                            pragma solidity >=0.8.0;
                            /// @notice Modern, minimalist, and gas efficient ERC-721 implementation.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
                            abstract contract ERC721 {
                                /*//////////////////////////////////////////////////////////////
                                                             EVENTS
                                //////////////////////////////////////////////////////////////*/
                                event Transfer(address indexed from, address indexed to, uint256 indexed id);
                                event Approval(address indexed owner, address indexed spender, uint256 indexed id);
                                event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
                                /*//////////////////////////////////////////////////////////////
                                                     METADATA STORAGE/LOGIC
                                //////////////////////////////////////////////////////////////*/
                                string public name;
                                string public symbol;
                                function tokenURI(uint256 id) public view virtual returns (string memory);
                                /*//////////////////////////////////////////////////////////////
                                                  ERC721 BALANCE/OWNER STORAGE
                                //////////////////////////////////////////////////////////////*/
                                mapping(uint256 => address) internal _ownerOf;
                                mapping(address => uint256) internal _balanceOf;
                                function ownerOf(uint256 id) public view virtual returns (address owner) {
                                    require((owner = _ownerOf[id]) != address(0), "NOT_MINTED");
                                }
                                function balanceOf(address owner) public view virtual returns (uint256) {
                                    require(owner != address(0), "ZERO_ADDRESS");
                                    return _balanceOf[owner];
                                }
                                /*//////////////////////////////////////////////////////////////
                                                     ERC721 APPROVAL STORAGE
                                //////////////////////////////////////////////////////////////*/
                                mapping(uint256 => address) public getApproved;
                                mapping(address => mapping(address => bool)) public isApprovedForAll;
                                /*//////////////////////////////////////////////////////////////
                                                           CONSTRUCTOR
                                //////////////////////////////////////////////////////////////*/
                                constructor(string memory _name, string memory _symbol) {
                                    name = _name;
                                    symbol = _symbol;
                                }
                                /*//////////////////////////////////////////////////////////////
                                                          ERC721 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function approve(address spender, uint256 id) public virtual {
                                    address owner = _ownerOf[id];
                                    require(msg.sender == owner || isApprovedForAll[owner][msg.sender], "NOT_AUTHORIZED");
                                    getApproved[id] = spender;
                                    emit Approval(owner, spender, id);
                                }
                                function setApprovalForAll(address operator, bool approved) public virtual {
                                    isApprovedForAll[msg.sender][operator] = approved;
                                    emit ApprovalForAll(msg.sender, operator, approved);
                                }
                                function transferFrom(
                                    address from,
                                    address to,
                                    uint256 id
                                ) public virtual {
                                    require(from == _ownerOf[id], "WRONG_FROM");
                                    require(to != address(0), "INVALID_RECIPIENT");
                                    require(
                                        msg.sender == from || isApprovedForAll[from][msg.sender] || msg.sender == getApproved[id],
                                        "NOT_AUTHORIZED"
                                    );
                                    // Underflow of the sender's balance is impossible because we check for
                                    // ownership above and the recipient's balance can't realistically overflow.
                                    unchecked {
                                        _balanceOf[from]--;
                                        _balanceOf[to]++;
                                    }
                                    _ownerOf[id] = to;
                                    delete getApproved[id];
                                    emit Transfer(from, to, id);
                                }
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 id
                                ) public virtual {
                                    transferFrom(from, to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, "") ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 id,
                                    bytes calldata data
                                ) public virtual {
                                    transferFrom(from, to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, data) ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                /*//////////////////////////////////////////////////////////////
                                                          ERC165 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
                                    return
                                        interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
                                        interfaceId == 0x80ac58cd || // ERC165 Interface ID for ERC721
                                        interfaceId == 0x5b5e139f; // ERC165 Interface ID for ERC721Metadata
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL MINT/BURN LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _mint(address to, uint256 id) internal virtual {
                                    require(to != address(0), "INVALID_RECIPIENT");
                                    require(_ownerOf[id] == address(0), "ALREADY_MINTED");
                                    // Counter overflow is incredibly unrealistic.
                                    unchecked {
                                        _balanceOf[to]++;
                                    }
                                    _ownerOf[id] = to;
                                    emit Transfer(address(0), to, id);
                                }
                                function _burn(uint256 id) internal virtual {
                                    address owner = _ownerOf[id];
                                    require(owner != address(0), "NOT_MINTED");
                                    // Ownership check above ensures no underflow.
                                    unchecked {
                                        _balanceOf[owner]--;
                                    }
                                    delete _ownerOf[id];
                                    delete getApproved[id];
                                    emit Transfer(owner, address(0), id);
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL SAFE MINT LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _safeMint(address to, uint256 id) internal virtual {
                                    _mint(to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, "") ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function _safeMint(
                                    address to,
                                    uint256 id,
                                    bytes memory data
                                ) internal virtual {
                                    _mint(to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, data) ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                            }
                            /// @notice A generic interface for a contract which properly accepts ERC721 tokens.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
                            abstract contract ERC721TokenReceiver {
                                function onERC721Received(
                                    address,
                                    address,
                                    uint256,
                                    bytes calldata
                                ) external virtual returns (bytes4) {
                                    return ERC721TokenReceiver.onERC721Received.selector;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (access/Ownable2Step.sol)
                            pragma solidity ^0.8.0;
                            import "./OwnableUpgradeable.sol";
                            import "../proxy/utils/Initializable.sol";
                            /**
                             * @dev Contract module which provides 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} and {acceptOwnership}.
                             *
                             * This module is used through inheritance. It will make available all functions
                             * from parent (Ownable).
                             */
                            abstract contract Ownable2StepUpgradeable is Initializable, OwnableUpgradeable {
                                function __Ownable2Step_init() internal onlyInitializing {
                                    __Ownable_init_unchained();
                                }
                                function __Ownable2Step_init_unchained() internal onlyInitializing {
                                }
                                address private _pendingOwner;
                                event OwnershipTransferStarted(address indexed previousOwner, address indexed newOwner);
                                /**
                                 * @dev Returns the address of the pending owner.
                                 */
                                function pendingOwner() public view virtual returns (address) {
                                    return _pendingOwner;
                                }
                                /**
                                 * @dev Starts the ownership transfer of the contract to a new account. Replaces the pending transfer if there is one.
                                 * Can only be called by the current owner.
                                 */
                                function transferOwnership(address newOwner) public virtual override onlyOwner {
                                    _pendingOwner = newOwner;
                                    emit OwnershipTransferStarted(owner(), newOwner);
                                }
                                /**
                                 * @dev Transfers ownership of the contract to a new account (`newOwner`) and deletes any pending owner.
                                 * Internal function without access restriction.
                                 */
                                function _transferOwnership(address newOwner) internal virtual override {
                                    delete _pendingOwner;
                                    super._transferOwnership(newOwner);
                                }
                                /**
                                 * @dev The new owner accepts the ownership transfer.
                                 */
                                function acceptOwnership() external {
                                    address sender = _msgSender();
                                    require(pendingOwner() == sender, "Ownable2Step: caller is not the new owner");
                                    _transferOwnership(sender);
                                }
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[49] private __gap;
                            }
                            // SPDX-License-Identifier: BSL 1.1 - Blend (c) Non Fungible Trading Ltd.
                            pragma solidity 0.8.17;
                            import "./Structs.sol";
                            import "./Errors.sol";
                            import "../interfaces/ISignatures.sol";
                            abstract contract Signatures is ISignatures {
                                bytes32 private immutable _LOAN_OFFER_TYPEHASH;
                                bytes32 private immutable _FEE_TYPEHASH;
                                bytes32 private immutable _SELL_OFFER_TYPEHASH;
                                bytes32 private immutable _ORACLE_OFFER_TYPEHASH;
                                bytes32 private immutable _EIP_712_DOMAIN_TYPEHASH;
                                string private constant _NAME = "Blend";
                                string private constant _VERSION = "1.0";
                                mapping(address => uint256) public nonces;
                                mapping(address => uint256) public oracles;
                                uint256 public blockRange;
                                uint256[50] private _gap;
                                constructor() {
                                    (
                                        _LOAN_OFFER_TYPEHASH,
                                        _SELL_OFFER_TYPEHASH,
                                        _FEE_TYPEHASH,
                                        _ORACLE_OFFER_TYPEHASH,
                                        _EIP_712_DOMAIN_TYPEHASH
                                    ) = _createTypehashes();
                                }
                                function information() external view returns (string memory version, bytes32 domainSeparator) {
                                    version = _VERSION;
                                    domainSeparator = _hashDomain(
                                        _EIP_712_DOMAIN_TYPEHASH,
                                        keccak256(bytes(_NAME)),
                                        keccak256(bytes(_VERSION))
                                    );
                                }
                                function getSellOfferHash(SellOffer calldata offer) external view returns (bytes32) {
                                    return _hashSellOffer(offer);
                                }
                                function getOfferHash(LoanOffer calldata offer) external view returns (bytes32) {
                                    return _hashOffer(offer);
                                }
                                function getOracleOfferHash(bytes32 hash, uint256 blockNumber) external view returns (bytes32) {
                                    return _hashOracleOffer(hash, blockNumber);
                                }
                                /**
                                 * @notice Generate all EIP712 Typehashes
                                 */
                                function _createTypehashes()
                                    internal
                                    view
                                    returns (
                                        bytes32 loanOfferTypehash,
                                        bytes32 sellOfferTypehash,
                                        bytes32 feeTypehash,
                                        bytes32 oracleOfferTypehash,
                                        bytes32 eip712DomainTypehash
                                    )
                                {
                                    eip712DomainTypehash = keccak256(
                                        bytes.concat(
                                            "EIP712Domain(",
                                            "string name,",
                                            "string version,",
                                            "uint256 chainId,",
                                            "address verifyingContract",
                                            ")"
                                        )
                                    );
                                    oracleOfferTypehash = keccak256(
                                        bytes.concat("OracleOffer(", "bytes32 hash,", "uint256 blockNumber", ")")
                                    );
                                    loanOfferTypehash = keccak256(
                                        bytes.concat(
                                            "LoanOffer(",
                                            "address lender,",
                                            "address collection,",
                                            "uint256 totalAmount,",
                                            "uint256 minAmount,",
                                            "uint256 maxAmount,",
                                            "uint256 auctionDuration,",
                                            "uint256 salt,",
                                            "uint256 expirationTime,",
                                            "uint256 rate,",
                                            "address oracle,",
                                            "uint256 nonce",
                                            ")"
                                        )
                                    );
                                    bytes memory feeTypestring = bytes.concat("Fee(", "uint16 rate,", "address recipient", ")");
                                    feeTypehash = keccak256(feeTypestring);
                                    sellOfferTypehash = keccak256(
                                        bytes.concat(
                                            "SellOffer(",
                                            "address borrower,",
                                            "uint256 lienId,",
                                            "uint256 price,",
                                            "uint256 expirationTime,",
                                            "uint256 salt,",
                                            "address oracle,",
                                            "Fee[] fees,",
                                            "uint256 nonce",
                                            ")",
                                            feeTypestring
                                        )
                                    );
                                }
                                function _hashDomain(
                                    bytes32 eip712DomainTypehash,
                                    bytes32 nameHash,
                                    bytes32 versionHash
                                ) internal view returns (bytes32) {
                                    return
                                        keccak256(
                                            abi.encode(
                                                eip712DomainTypehash,
                                                nameHash,
                                                versionHash,
                                                block.chainid,
                                                address(this)
                                            )
                                        );
                                }
                                function _hashFee(Fee calldata fee) internal view returns (bytes32) {
                                    return keccak256(abi.encode(_FEE_TYPEHASH, fee.rate, fee.recipient));
                                }
                                function _packFees(Fee[] calldata fees) internal view returns (bytes32) {
                                    bytes32[] memory feeHashes = new bytes32[](fees.length);
                                    uint256 feesLength = fees.length;
                                    for (uint256 i; i < feesLength; ) {
                                        feeHashes[i] = _hashFee(fees[i]);
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                    return keccak256(abi.encodePacked(feeHashes));
                                }
                                function _hashSellOffer(SellOffer calldata offer) internal view returns (bytes32) {
                                    return
                                        keccak256(
                                            abi.encode(
                                                _SELL_OFFER_TYPEHASH,
                                                offer.borrower,
                                                offer.lienId,
                                                offer.price,
                                                offer.expirationTime,
                                                offer.salt,
                                                offer.oracle,
                                                _packFees(offer.fees),
                                                nonces[offer.borrower]
                                            )
                                        );
                                }
                                function _hashOffer(LoanOffer calldata offer) internal view returns (bytes32) {
                                    return
                                        keccak256(
                                            abi.encode(
                                                _LOAN_OFFER_TYPEHASH,
                                                offer.lender,
                                                offer.collection,
                                                offer.totalAmount,
                                                offer.minAmount,
                                                offer.maxAmount,
                                                offer.auctionDuration,
                                                offer.salt,
                                                offer.expirationTime,
                                                offer.rate,
                                                offer.oracle,
                                                nonces[offer.lender]
                                            )
                                        );
                                }
                                function _hashOracleOffer(bytes32 hash, uint256 blockNumber) internal view returns (bytes32) {
                                    return keccak256(abi.encode(_ORACLE_OFFER_TYPEHASH, hash, blockNumber));
                                }
                                function _hashToSign(bytes32 hash) internal view returns (bytes32) {
                                    return keccak256(
                                        bytes.concat(
                                            bytes2(0x1901),
                                            _hashDomain(
                                                _EIP_712_DOMAIN_TYPEHASH,
                                                keccak256(bytes(_NAME)),
                                                keccak256(bytes(_VERSION))
                                            ),
                                            hash
                                        )
                                    );
                                }
                                function _hashToSignOracle(bytes32 hash, uint256 blockNumber) internal view returns (bytes32) {
                                    return
                                        keccak256(
                                            bytes.concat(
                                                bytes2(0x1901),
                                                _hashDomain(
                                                    _EIP_712_DOMAIN_TYPEHASH,
                                                    keccak256(bytes(_NAME)),
                                                    keccak256(bytes(_VERSION))
                                                ),
                                                _hashOracleOffer(hash, blockNumber)
                                            )
                                        );
                                }
                                /**
                                 * @notice Verify authorization of offer
                                 * @param offerHash Hash of offer struct
                                 * @param lender Lender address
                                 * @param oracle Oracle address
                                 * @param signature Packed offer signature (with oracle signature if necessary)
                                 */
                                function _verifyOfferAuthorization(
                                    bytes32 offerHash,
                                    address lender,
                                    address oracle,
                                    bytes calldata signature
                                ) internal view {
                                    bytes32 hashToSign = _hashToSign(offerHash);
                                    bytes32 r;
                                    bytes32 s;
                                    uint8 v;
                                    assembly {
                                        r := calldataload(signature.offset)
                                        s := calldataload(add(signature.offset, 0x20))
                                        v := shr(248, calldataload(add(signature.offset, 0x40)))
                                    }
                                    _verify(lender, hashToSign, v, r, s);
                                    /* Verify oracle signature if required. */
                                    if (oracle != address(0)) {
                                        uint256 blockNumber;
                                        assembly {
                                            r := calldataload(add(signature.offset, 0x41))
                                            s := calldataload(add(signature.offset, 0x61))
                                            v := shr(248, calldataload(add(signature.offset, 0x81)))
                                            blockNumber := calldataload(add(signature.offset, 0x82))
                                        }
                                        if (oracles[oracle] == 0) {
                                            revert UnauthorizedOracle();
                                        }
                                        if (blockNumber + blockRange < block.number) {
                                            revert SignatureExpired();
                                        }
                                        hashToSign = _hashToSignOracle(offerHash, blockNumber);
                                        _verify(oracle, hashToSign, v, r, s);
                                    }
                                }
                                /**
                                 * @notice Verify signature of digest
                                 * @param signer Address of expected signer
                                 * @param digest Signature digest
                                 * @param v v parameter
                                 * @param r r parameter
                                 * @param s s parameter
                                 */
                                function _verify(address signer, bytes32 digest, uint8 v, bytes32 r, bytes32 s) internal pure {
                                    if (v != 27 && v != 28) {
                                        revert InvalidVParameter();
                                    }
                                    address recoveredSigner = ecrecover(digest, v, r, s);
                                    if (recoveredSigner == address(0) || signer != recoveredSigner) {
                                        revert InvalidSignature();
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "./ISignatures.sol";
                            interface IOfferController is ISignatures {
                                event OfferCancelled(address indexed user, uint256 salt);
                                event NonceIncremented(address indexed user, uint256 newNonce);
                                function cancelOffer(uint256 salt) external;
                                function cancelOffers(uint256[] calldata salts) external;
                                function incrementNonce() external;
                                /* Admin */
                                function setOracle(address oracle, bool approved) external;
                                function setBlockRange(uint256 blockRange) external;
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.7.0) (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 {
                                    __Ownable_init_unchained();
                                }
                                function __Ownable_init_unchained() internal onlyInitializing {
                                    _transferOwnership(_msgSender());
                                }
                                /**
                                 * @dev Throws if called by any account other than the owner.
                                 */
                                modifier onlyOwner() {
                                    _checkOwner();
                                    _;
                                }
                                /**
                                 * @dev Returns the address of the current owner.
                                 */
                                function owner() public view virtual returns (address) {
                                    return _owner;
                                }
                                /**
                                 * @dev Throws if the sender is not the owner.
                                 */
                                function _checkOwner() internal view virtual {
                                    require(owner() == _msgSender(), "Ownable: caller is not the owner");
                                }
                                /**
                                 * @dev Leaves the contract without owner. It will not be possible to call
                                 * `onlyOwner` functions anymore. Can only be called by the current owner.
                                 *
                                 * NOTE: Renouncing ownership will leave the contract without an owner,
                                 * thereby removing any functionality that is only available to the owner.
                                 */
                                function renounceOwnership() public virtual onlyOwner {
                                    _transferOwnership(address(0));
                                }
                                /**
                                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                                 * Can only be called by the current owner.
                                 */
                                function transferOwnership(address newOwner) public virtual onlyOwner {
                                    require(newOwner != address(0), "Ownable: new owner is the zero address");
                                    _transferOwnership(newOwner);
                                }
                                /**
                                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                                 * Internal function without access restriction.
                                 */
                                function _transferOwnership(address newOwner) internal virtual {
                                    address oldOwner = _owner;
                                    _owner = newOwner;
                                    emit OwnershipTransferred(oldOwner, newOwner);
                                }
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[49] private __gap;
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                            pragma solidity ^0.8.0;
                            import "../proxy/utils/Initializable.sol";
                            /**
                             * @dev Provides information about the current execution context, including the
                             * sender of the transaction and its data. While these are generally available
                             * via msg.sender and msg.data, they should not be accessed in such a direct
                             * manner, since when dealing with meta-transactions the account sending and
                             * paying for execution may not be the actual sender (as far as an application
                             * is concerned).
                             *
                             * This contract is only required for intermediate, library-like contracts.
                             */
                            abstract contract ContextUpgradeable is Initializable {
                                function __Context_init() internal onlyInitializing {
                                }
                                function __Context_init_unchained() internal onlyInitializing {
                                }
                                function _msgSender() internal view virtual returns (address) {
                                    return msg.sender;
                                }
                                function _msgData() internal view virtual returns (bytes calldata) {
                                    return msg.data;
                                }
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[50] private __gap;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "../lib/Structs.sol";
                            interface ISignatures {
                                function information()
                                    external
                                    view
                                    returns (
                                        string memory version,
                                        bytes32 domainSeparator
                                    );
                                function getOracleOfferHash(bytes32 hash, uint256 blockNumber) external view returns (bytes32);
                                function getSellOfferHash(SellOffer calldata offer) external view returns (bytes32);
                                function getOfferHash(LoanOffer calldata offer) external view returns (bytes32);
                                function cancelledOrFulfilled(address user, uint256 salt) external view returns (uint256);
                                function nonces(address user) external view returns (uint256);
                            }
                            

                            File 4 of 6: BlurPool
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            import "lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/UUPSUpgradeable.sol";
                            import "lib/openzeppelin-contracts-upgradeable/contracts/access/OwnableUpgradeable.sol";
                            import "./interfaces/IBlurPool.sol";
                            /**
                             * @title BlurPool
                             * @dev ETH pool; funds can only be transferred by Exchange, ExchangeV2, Swap or Blend
                             */
                            contract BlurPool is IBlurPool, OwnableUpgradeable, UUPSUpgradeable {
                                address private immutable EXCHANGE;
                                address private immutable EXCHANGE_V2;
                                address private immutable SWAP;
                                address private immutable BLEND;
                                mapping(address => uint256) private _balances;
                                string public constant name = 'Blur Pool';
                                string constant symbol = '';
                                // required by the OZ UUPS module
                                function _authorizeUpgrade(address) internal override onlyOwner {}
                                constructor(address exchange, address exchangeV2, address swap, address blend) {
                                    _disableInitializers();
                                    EXCHANGE = exchange;
                                    EXCHANGE_V2 = exchangeV2;
                                    SWAP = swap;
                                    BLEND = blend;
                                }
                                /* Constructor (for ERC1967) */
                                function initialize() external initializer {
                                    __Ownable_init();
                                }
                                function decimals() external pure returns (uint8) {
                                    return 18;
                                }
                                function totalSupply() external view returns (uint256) {
                                    return address(this).balance;
                                }
                                function balanceOf(address user) external view returns (uint256) {
                                    return _balances[user];
                                }
                                /**
                                 * @dev receive deposit function
                                 */
                                receive() external payable {
                                    deposit();
                                }
                                /**
                                 * @dev deposit ETH into pool
                                 */
                                function deposit() public payable {
                                    _balances[msg.sender] += msg.value;
                                    emit Transfer(address(0), msg.sender, msg.value);
                                }
                                /**
                                 * @dev deposit ETH into pool on behalf of user
                                 * @param user Address to deposit to
                                 */
                                function deposit(address user) public payable {
                                    if (msg.sender != BLEND && msg.sender != EXCHANGE_V2) {
                                        revert('Unauthorized deposit');
                                    }
                                    _balances[user] += msg.value;
                                    emit Transfer(address(0), user, msg.value);
                                }
                                /**
                                 * @dev withdraw ETH from pool
                                 * @param amount Amount to withdraw
                                 */
                                function withdraw(uint256 amount) external {
                                    uint256 balance = _balances[msg.sender];
                                    require(balance >= amount, "Insufficient funds");
                                    unchecked {
                                        _balances[msg.sender] = balance - amount;
                                    }
                                    (bool success,) = payable(msg.sender).call{value: amount}("");
                                    require(success, "Transfer failed");
                                    emit Transfer(msg.sender, address(0), amount);
                                }
                                /**
                                 * @dev withdraw ETH from pool on behalf of user; only callable by Blend
                                 * @param from Address to withdraw from
                                 * @param to Address to withdraw to
                                 * @param amount Amount to withdraw
                                 */
                                function withdrawFrom(address from, address to, uint256 amount) external {
                                    if (msg.sender != BLEND && msg.sender != EXCHANGE_V2) {
                                        revert('Unauthorized transfer');
                                    }
                                    uint256 balance = _balances[from];
                                    require(balance >= amount, "Insufficient balance");
                                    unchecked {
                                        _balances[from] = balance - amount;
                                    }
                                    (bool success,) = payable(to).call{value: amount}("");
                                    require(success, "Transfer failed");
                                    emit Transfer(from, address(0), amount);
                                }
                                /**
                                 * @dev transferFrom Transfer balances within pool; only callable by Swap, Exchange, and Blend
                                 * @param from Pool fund sender
                                 * @param to Pool fund recipient
                                 * @param amount Amount to transfer
                                 */
                                function transferFrom(address from, address to, uint256 amount)
                                    external
                                    returns (bool)
                                {
                                    if (
                                        msg.sender != EXCHANGE &&
                                        msg.sender != EXCHANGE_V2 &&
                                        msg.sender != SWAP &&
                                        msg.sender != BLEND
                                    ) {
                                        revert('Unauthorized transfer');
                                    }
                                    _transfer(from, to, amount);
                                    return true;
                                }
                                function _transfer(address from, address to, uint256 amount) private {
                                    require(to != address(0), "Cannot transfer to 0 address");
                                    uint256 balance = _balances[from];
                                    require(balance >= amount, "Insufficient balance");
                                    unchecked {
                                        _balances[from] = balance - amount;
                                    }
                                    _balances[to] += amount;
                                    emit Transfer(from, to, amount);
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (proxy/utils/UUPSUpgradeable.sol)
                            pragma solidity ^0.8.0;
                            import "../../interfaces/draft-IERC1822Upgradeable.sol";
                            import "../ERC1967/ERC1967UpgradeUpgradeable.sol";
                            import "./Initializable.sol";
                            /**
                             * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
                             * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
                             *
                             * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
                             * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
                             * `UUPSUpgradeable` with a custom implementation of upgrades.
                             *
                             * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
                             *
                             * _Available since v4.1._
                             */
                            abstract contract UUPSUpgradeable is Initializable, IERC1822ProxiableUpgradeable, ERC1967UpgradeUpgradeable {
                                function __UUPSUpgradeable_init() internal onlyInitializing {
                                }
                                function __UUPSUpgradeable_init_unchained() internal onlyInitializing {
                                }
                                /// @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
                                address private immutable __self = address(this);
                                /**
                                 * @dev Check that the execution is being performed through a delegatecall call and that the execution context is
                                 * a proxy contract with an implementation (as defined in ERC1967) pointing to self. This should only be the case
                                 * for UUPS and transparent proxies that are using the current contract as their implementation. Execution of a
                                 * function through ERC1167 minimal proxies (clones) would not normally pass this test, but is not guaranteed to
                                 * fail.
                                 */
                                modifier onlyProxy() {
                                    require(address(this) != __self, "Function must be called through delegatecall");
                                    require(_getImplementation() == __self, "Function must be called through active proxy");
                                    _;
                                }
                                /**
                                 * @dev Check that the execution is not being performed through a delegate call. This allows a function to be
                                 * callable on the implementing contract but not through proxies.
                                 */
                                modifier notDelegated() {
                                    require(address(this) == __self, "UUPSUpgradeable: must not be called through delegatecall");
                                    _;
                                }
                                /**
                                 * @dev Implementation of the ERC1822 {proxiableUUID} function. This returns the storage slot used by the
                                 * implementation. It is used to validate the implementation's compatibility when performing an upgrade.
                                 *
                                 * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
                                 * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
                                 * function revert if invoked through a proxy. This is guaranteed by the `notDelegated` modifier.
                                 */
                                function proxiableUUID() external view virtual override notDelegated returns (bytes32) {
                                    return _IMPLEMENTATION_SLOT;
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy to `newImplementation`.
                                 *
                                 * Calls {_authorizeUpgrade}.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function upgradeTo(address newImplementation) external virtual onlyProxy {
                                    _authorizeUpgrade(newImplementation);
                                    _upgradeToAndCallUUPS(newImplementation, new bytes(0), false);
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
                                 * encoded in `data`.
                                 *
                                 * Calls {_authorizeUpgrade}.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual onlyProxy {
                                    _authorizeUpgrade(newImplementation);
                                    _upgradeToAndCallUUPS(newImplementation, data, true);
                                }
                                /**
                                 * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
                                 * {upgradeTo} and {upgradeToAndCall}.
                                 *
                                 * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
                                 *
                                 * ```solidity
                                 * function _authorizeUpgrade(address) internal override onlyOwner {}
                                 * ```
                                 */
                                function _authorizeUpgrade(address newImplementation) internal virtual;
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[50] private __gap;
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.7.0) (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 {
                                    __Ownable_init_unchained();
                                }
                                function __Ownable_init_unchained() internal onlyInitializing {
                                    _transferOwnership(_msgSender());
                                }
                                /**
                                 * @dev Throws if called by any account other than the owner.
                                 */
                                modifier onlyOwner() {
                                    _checkOwner();
                                    _;
                                }
                                /**
                                 * @dev Returns the address of the current owner.
                                 */
                                function owner() public view virtual returns (address) {
                                    return _owner;
                                }
                                /**
                                 * @dev Throws if the sender is not the owner.
                                 */
                                function _checkOwner() internal view virtual {
                                    require(owner() == _msgSender(), "Ownable: caller is not the owner");
                                }
                                /**
                                 * @dev Leaves the contract without owner. It will not be possible to call
                                 * `onlyOwner` functions anymore. Can only be called by the current owner.
                                 *
                                 * NOTE: Renouncing ownership will leave the contract without an owner,
                                 * thereby removing any functionality that is only available to the owner.
                                 */
                                function renounceOwnership() public virtual onlyOwner {
                                    _transferOwnership(address(0));
                                }
                                /**
                                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                                 * Can only be called by the current owner.
                                 */
                                function transferOwnership(address newOwner) public virtual onlyOwner {
                                    require(newOwner != address(0), "Ownable: new owner is the zero address");
                                    _transferOwnership(newOwner);
                                }
                                /**
                                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                                 * Internal function without access restriction.
                                 */
                                function _transferOwnership(address newOwner) internal virtual {
                                    address oldOwner = _owner;
                                    _owner = newOwner;
                                    emit OwnershipTransferred(oldOwner, newOwner);
                                }
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[49] private __gap;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            interface IBlurPool {
                                event Transfer(address indexed from, address indexed to, uint256 amount);
                                function initialize() external;
                                function decimals() external pure returns (uint8);
                                function totalSupply() external view returns (uint256);
                                function balanceOf(address user) external view returns (uint256);
                                function deposit() external payable;
                                function deposit(address user) external payable;
                                function withdraw(uint256 amount) external;
                                function withdrawFrom(address from, address to, uint256 amount) external;
                                function transferFrom(address from, address to, uint256 amount) external returns (bool);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
                             * proxy whose upgrades are fully controlled by the current implementation.
                             */
                            interface IERC1822ProxiableUpgradeable {
                                /**
                                 * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
                                 * address.
                                 *
                                 * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
                                 * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
                                 * function revert if invoked through a proxy.
                                 */
                                function proxiableUUID() external view returns (bytes32);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.3) (proxy/ERC1967/ERC1967Upgrade.sol)
                            pragma solidity ^0.8.2;
                            import "../beacon/IBeaconUpgradeable.sol";
                            import "../../interfaces/IERC1967Upgradeable.sol";
                            import "../../interfaces/draft-IERC1822Upgradeable.sol";
                            import "../../utils/AddressUpgradeable.sol";
                            import "../../utils/StorageSlotUpgradeable.sol";
                            import "../utils/Initializable.sol";
                            /**
                             * @dev This abstract contract provides getters and event emitting update functions for
                             * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
                             *
                             * _Available since v4.1._
                             *
                             * @custom:oz-upgrades-unsafe-allow delegatecall
                             */
                            abstract contract ERC1967UpgradeUpgradeable is Initializable, IERC1967Upgradeable {
                                function __ERC1967Upgrade_init() internal onlyInitializing {
                                }
                                function __ERC1967Upgrade_init_unchained() internal onlyInitializing {
                                }
                                // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
                                bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
                                /**
                                 * @dev Storage slot with the address of the current implementation.
                                 * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                                /**
                                 * @dev Returns the current implementation address.
                                 */
                                function _getImplementation() internal view returns (address) {
                                    return StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new address in the EIP1967 implementation slot.
                                 */
                                function _setImplementation(address newImplementation) private {
                                    require(AddressUpgradeable.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                                    StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                                }
                                /**
                                 * @dev Perform implementation upgrade
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeTo(address newImplementation) internal {
                                    _setImplementation(newImplementation);
                                    emit Upgraded(newImplementation);
                                }
                                /**
                                 * @dev Perform implementation upgrade with additional setup call.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeToAndCall(
                                    address newImplementation,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    _upgradeTo(newImplementation);
                                    if (data.length > 0 || forceCall) {
                                        _functionDelegateCall(newImplementation, data);
                                    }
                                }
                                /**
                                 * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
                                 *
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeToAndCallUUPS(
                                    address newImplementation,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    // Upgrades from old implementations will perform a rollback test. This test requires the new
                                    // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                                    // this special case will break upgrade paths from old UUPS implementation to new ones.
                                    if (StorageSlotUpgradeable.getBooleanSlot(_ROLLBACK_SLOT).value) {
                                        _setImplementation(newImplementation);
                                    } else {
                                        try IERC1822ProxiableUpgradeable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                                            require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                                        } catch {
                                            revert("ERC1967Upgrade: new implementation is not UUPS");
                                        }
                                        _upgradeToAndCall(newImplementation, data, forceCall);
                                    }
                                }
                                /**
                                 * @dev Storage slot with the admin of the contract.
                                 * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                                /**
                                 * @dev Returns the current admin.
                                 */
                                function _getAdmin() internal view returns (address) {
                                    return StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new address in the EIP1967 admin slot.
                                 */
                                function _setAdmin(address newAdmin) private {
                                    require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                                    StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
                                }
                                /**
                                 * @dev Changes the admin of the proxy.
                                 *
                                 * Emits an {AdminChanged} event.
                                 */
                                function _changeAdmin(address newAdmin) internal {
                                    emit AdminChanged(_getAdmin(), newAdmin);
                                    _setAdmin(newAdmin);
                                }
                                /**
                                 * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
                                 * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
                                 */
                                bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
                                /**
                                 * @dev Returns the current beacon.
                                 */
                                function _getBeacon() internal view returns (address) {
                                    return StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value;
                                }
                                /**
                                 * @dev Stores a new beacon in the EIP1967 beacon slot.
                                 */
                                function _setBeacon(address newBeacon) private {
                                    require(AddressUpgradeable.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                                    require(
                                        AddressUpgradeable.isContract(IBeaconUpgradeable(newBeacon).implementation()),
                                        "ERC1967: beacon implementation is not a contract"
                                    );
                                    StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value = newBeacon;
                                }
                                /**
                                 * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
                                 * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
                                 *
                                 * Emits a {BeaconUpgraded} event.
                                 */
                                function _upgradeBeaconToAndCall(
                                    address newBeacon,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    _setBeacon(newBeacon);
                                    emit BeaconUpgraded(newBeacon);
                                    if (data.length > 0 || forceCall) {
                                        _functionDelegateCall(IBeaconUpgradeable(newBeacon).implementation(), data);
                                    }
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                                 * but performing a delegate call.
                                 *
                                 * _Available since v3.4._
                                 */
                                function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
                                    require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, bytes memory returndata) = target.delegatecall(data);
                                    return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
                                }
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[50] private __gap;
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.1) (proxy/utils/Initializable.sol)
                            pragma solidity ^0.8.2;
                            import "../../utils/AddressUpgradeable.sol";
                            /**
                             * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                             * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                             * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                             * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                             *
                             * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                             * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                             * case an upgrade adds a module that needs to be initialized.
                             *
                             * For example:
                             *
                             * [.hljs-theme-light.nopadding]
                             * ```
                             * contract MyToken is ERC20Upgradeable {
                             *     function initialize() initializer public {
                             *         __ERC20_init("MyToken", "MTK");
                             *     }
                             * }
                             * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                             *     function initializeV2() reinitializer(2) public {
                             *         __ERC20Permit_init("MyToken");
                             *     }
                             * }
                             * ```
                             *
                             * 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 prevent the implementation contract from being used, you should invoke
                             * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                             *
                             * [.hljs-theme-light.nopadding]
                             * ```
                             * /// @custom:oz-upgrades-unsafe-allow constructor
                             * constructor() {
                             *     _disableInitializers();
                             * }
                             * ```
                             * ====
                             */
                            abstract contract Initializable {
                                /**
                                 * @dev Indicates that the contract has been initialized.
                                 * @custom:oz-retyped-from bool
                                 */
                                uint8 private _initialized;
                                /**
                                 * @dev Indicates that the contract is in the process of being initialized.
                                 */
                                bool private _initializing;
                                /**
                                 * @dev Triggered when the contract has been initialized or reinitialized.
                                 */
                                event Initialized(uint8 version);
                                /**
                                 * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                                 * `onlyInitializing` functions can be used to initialize parent contracts.
                                 *
                                 * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
                                 * constructor.
                                 *
                                 * Emits an {Initialized} event.
                                 */
                                modifier initializer() {
                                    bool isTopLevelCall = !_initializing;
                                    require(
                                        (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                                        "Initializable: contract is already initialized"
                                    );
                                    _initialized = 1;
                                    if (isTopLevelCall) {
                                        _initializing = true;
                                    }
                                    _;
                                    if (isTopLevelCall) {
                                        _initializing = false;
                                        emit Initialized(1);
                                    }
                                }
                                /**
                                 * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                                 * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                                 * used to initialize parent contracts.
                                 *
                                 * A reinitializer may be used after the original initialization step. This is essential to configure modules that
                                 * are added through upgrades and that require initialization.
                                 *
                                 * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
                                 * cannot be nested. If one is invoked in the context of another, execution will revert.
                                 *
                                 * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                                 * a contract, executing them in the right order is up to the developer or operator.
                                 *
                                 * WARNING: setting the version to 255 will prevent any future reinitialization.
                                 *
                                 * Emits an {Initialized} event.
                                 */
                                modifier reinitializer(uint8 version) {
                                    require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                                    _initialized = version;
                                    _initializing = true;
                                    _;
                                    _initializing = false;
                                    emit Initialized(version);
                                }
                                /**
                                 * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                                 * {initializer} and {reinitializer} modifiers, directly or indirectly.
                                 */
                                modifier onlyInitializing() {
                                    require(_initializing, "Initializable: contract is not initializing");
                                    _;
                                }
                                /**
                                 * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                                 * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                                 * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                                 * through proxies.
                                 *
                                 * Emits an {Initialized} event the first time it is successfully executed.
                                 */
                                function _disableInitializers() internal virtual {
                                    require(!_initializing, "Initializable: contract is initializing");
                                    if (_initialized < type(uint8).max) {
                                        _initialized = type(uint8).max;
                                        emit Initialized(type(uint8).max);
                                    }
                                }
                                /**
                                 * @dev Returns the highest version that has been initialized. See {reinitializer}.
                                 */
                                function _getInitializedVersion() internal view returns (uint8) {
                                    return _initialized;
                                }
                                /**
                                 * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
                                 */
                                function _isInitializing() internal view returns (bool) {
                                    return _initializing;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev This is the interface that {BeaconProxy} expects of its beacon.
                             */
                            interface IBeaconUpgradeable {
                                /**
                                 * @dev Must return an address that can be used as a delegate call target.
                                 *
                                 * {BeaconProxy} will check that this address is a contract.
                                 */
                                function implementation() external view returns (address);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.3) (interfaces/IERC1967.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev ERC-1967: Proxy Storage Slots. This interface contains the events defined in the ERC.
                             *
                             * _Available since v4.9._
                             */
                            interface IERC1967Upgradeable {
                                /**
                                 * @dev Emitted when the implementation is upgraded.
                                 */
                                event Upgraded(address indexed implementation);
                                /**
                                 * @dev Emitted when the admin account has changed.
                                 */
                                event AdminChanged(address previousAdmin, address newAdmin);
                                /**
                                 * @dev Emitted when the beacon is changed.
                                 */
                                event BeaconUpgraded(address indexed beacon);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
                            pragma solidity ^0.8.1;
                            /**
                             * @dev Collection of functions related to the address type
                             */
                            library AddressUpgradeable {
                                /**
                                 * @dev Returns true if `account` is a contract.
                                 *
                                 * [IMPORTANT]
                                 * ====
                                 * It is unsafe to assume that an address for which this function returns
                                 * false is an externally-owned account (EOA) and not a contract.
                                 *
                                 * Among others, `isContract` will return false for the following
                                 * types of addresses:
                                 *
                                 *  - an externally-owned account
                                 *  - a contract in construction
                                 *  - an address where a contract will be created
                                 *  - an address where a contract lived, but was destroyed
                                 * ====
                                 *
                                 * [IMPORTANT]
                                 * ====
                                 * You shouldn't rely on `isContract` to protect against flash loan attacks!
                                 *
                                 * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                                 * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                                 * constructor.
                                 * ====
                                 */
                                function isContract(address account) internal view returns (bool) {
                                    // This method relies on extcodesize/address.code.length, which returns 0
                                    // for contracts in construction, since the code is only stored at the end
                                    // of the constructor execution.
                                    return account.code.length > 0;
                                }
                                /**
                                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                                 * `recipient`, forwarding all available gas and reverting on errors.
                                 *
                                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                                 * imposed by `transfer`, making them unable to receive funds via
                                 * `transfer`. {sendValue} removes this limitation.
                                 *
                                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                                 *
                                 * IMPORTANT: because control is transferred to `recipient`, care must be
                                 * taken to not create reentrancy vulnerabilities. Consider using
                                 * {ReentrancyGuard} or the
                                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                                 */
                                function sendValue(address payable recipient, uint256 amount) internal {
                                    require(address(this).balance >= amount, "Address: insufficient balance");
                                    (bool success, ) = recipient.call{value: amount}("");
                                    require(success, "Address: unable to send value, recipient may have reverted");
                                }
                                /**
                                 * @dev Performs a Solidity function call using a low level `call`. A
                                 * plain `call` is an unsafe replacement for a function call: use this
                                 * function instead.
                                 *
                                 * If `target` reverts with a revert reason, it is bubbled up by this
                                 * function (like regular Solidity function calls).
                                 *
                                 * Returns the raw returned data. To convert to the expected return value,
                                 * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                                 *
                                 * Requirements:
                                 *
                                 * - `target` must be a contract.
                                 * - calling `target` with `data` must not revert.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, 0, "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");
                                    (bool success, bytes memory returndata) = target.call{value: value}(data);
                                    return verifyCallResultFromTarget(target, 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) {
                                    (bool success, bytes memory returndata) = target.staticcall(data);
                                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                                }
                                /**
                                 * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
                                 * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
                                 *
                                 * _Available since v4.8._
                                 */
                                function verifyCallResultFromTarget(
                                    address target,
                                    bool success,
                                    bytes memory returndata,
                                    string memory errorMessage
                                ) internal view returns (bytes memory) {
                                    if (success) {
                                        if (returndata.length == 0) {
                                            // only check isContract if the call was successful and the return data is empty
                                            // otherwise we already know that it was a contract
                                            require(isContract(target), "Address: call to non-contract");
                                        }
                                        return returndata;
                                    } else {
                                        _revert(returndata, errorMessage);
                                    }
                                }
                                /**
                                 * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
                                 * revert reason or 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 {
                                        _revert(returndata, errorMessage);
                                    }
                                }
                                function _revert(bytes memory returndata, string memory errorMessage) private pure {
                                    // Look for revert reason and bubble it up if present
                                    if (returndata.length > 0) {
                                        // The easiest way to bubble the revert reason is using memory via assembly
                                        /// @solidity memory-safe-assembly
                                        assembly {
                                            let returndata_size := mload(returndata)
                                            revert(add(32, returndata), returndata_size)
                                        }
                                    } else {
                                        revert(errorMessage);
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev Library for reading and writing primitive types to specific storage slots.
                             *
                             * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
                             * This library helps with reading and writing to such slots without the need for inline assembly.
                             *
                             * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
                             *
                             * Example usage to set ERC1967 implementation slot:
                             * ```
                             * contract ERC1967 {
                             *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                             *
                             *     function _getImplementation() internal view returns (address) {
                             *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                             *     }
                             *
                             *     function _setImplementation(address newImplementation) internal {
                             *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                             *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                             *     }
                             * }
                             * ```
                             *
                             * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
                             */
                            library StorageSlotUpgradeable {
                                struct AddressSlot {
                                    address value;
                                }
                                struct BooleanSlot {
                                    bool value;
                                }
                                struct Bytes32Slot {
                                    bytes32 value;
                                }
                                struct Uint256Slot {
                                    uint256 value;
                                }
                                /**
                                 * @dev Returns an `AddressSlot` with member `value` located at `slot`.
                                 */
                                function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
                                 */
                                function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
                                 */
                                function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                                /**
                                 * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
                                 */
                                function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r.slot := slot
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                            pragma solidity ^0.8.0;
                            import "../proxy/utils/Initializable.sol";
                            /**
                             * @dev Provides information about the current execution context, including the
                             * sender of the transaction and its data. While these are generally available
                             * via msg.sender and msg.data, they should not be accessed in such a direct
                             * manner, since when dealing with meta-transactions the account sending and
                             * paying for execution may not be the actual sender (as far as an application
                             * is concerned).
                             *
                             * This contract is only required for intermediate, library-like contracts.
                             */
                            abstract contract ContextUpgradeable is Initializable {
                                function __Context_init() internal onlyInitializing {
                                }
                                function __Context_init_unchained() internal onlyInitializing {
                                }
                                function _msgSender() internal view virtual returns (address) {
                                    return msg.sender;
                                }
                                function _msgData() internal view virtual returns (bytes calldata) {
                                    return msg.data;
                                }
                                /**
                                 * @dev This empty reserved space is put in place to allow future versions to add new
                                 * variables without shifting down storage in the inheritance chain.
                                 * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                                 */
                                uint256[50] private __gap;
                            }
                            

                            File 5 of 6: Helpers
                            // SPDX-License-Identifier: BSL 1.1 - Blend (c) Non Fungible Trading Ltd.
                            pragma solidity 0.8.17;
                            import "lib/solmate/src/utils/SignedWadMath.sol";
                            import { InvalidRepayment } from "./lib/Errors.sol";
                            import "./lib/Structs.sol";
                            import "../pool/interfaces/IBlurPool.sol";
                            import { IBlurExchangeV2 as IExchangeV2 } from "../exchangeV2/interfaces/IBlurExchangeV2.sol";
                            import { Order as OrderV1, SignatureVersion, Side } from "../exchangeV1/lib/OrderStructs.sol";
                            import {
                                TakeAskSingle,
                                TakeBidSingle,
                                FeeRate,
                                Taker,
                                Exchange,
                                Order as OrderV2,
                                AssetType
                            } from "../exchangeV2/lib/Structs.sol";
                            interface IExchange {
                                function execute(Input calldata sell, Input calldata buy) external payable;
                            }
                            library Helpers {
                                int256 private constant _YEAR_WAD = 365 days * 1e18;
                                uint256 private constant _LIQUIDATION_THRESHOLD = 100_000;
                                uint256 private constant _BASIS_POINTS = 10_000;
                                error InvalidExecution();
                                /**
                                 * @dev Computes the current debt of a borrow given the last time it was touched and the last computed debt.
                                 * @param amount Principal in ETH
                                 * @param startTime Start time of the loan
                                 * @param rate Interest rate (in bips)
                                 * @dev Formula: https://www.desmos.com/calculator/l6omp0rwnh
                                 */
                                function computeCurrentDebt(
                                    uint256 amount,
                                    uint256 rate,
                                    uint256 startTime
                                ) public view returns (uint256) {
                                    uint256 loanTime = block.timestamp - startTime;
                                    int256 yearsWad = wadDiv(int256(loanTime) * 1e18, _YEAR_WAD);
                                    return uint256(wadMul(int256(amount), wadExp(wadMul(yearsWad, bipsToSignedWads(rate)))));
                                }
                                /**
                                 * @dev Calculates the current maximum interest rate a specific refinancing
                                 * auction could settle at currently given the auction's start block and duration.
                                 * @param startBlock The block the auction started at
                                 * @param oldRate Previous interest rate (in bips)
                                 * @dev Formula: https://www.desmos.com/calculator/urasr71dhb
                                 */
                                function calcRefinancingAuctionRate(
                                    uint256 startBlock,
                                    uint256 auctionDuration,
                                    uint256 oldRate
                                ) public view returns (uint256) {
                                    uint256 currentAuctionBlock = block.number - startBlock;
                                    int256 oldRateWads = bipsToSignedWads(oldRate);
                                    uint256 auctionT1 = auctionDuration / 5;
                                    uint256 auctionT2 = (4 * auctionDuration) / 5;
                                    int256 maxRateWads;
                                    {
                                        int256 aInverse = -bipsToSignedWads(15000);
                                        int256 b = 2;
                                        int256 maxMinRateWads = bipsToSignedWads(500);
                                        if (oldRateWads < -((b * aInverse) / 2)) {
                                            maxRateWads = maxMinRateWads + (oldRateWads ** 2) / aInverse + b * oldRateWads;
                                        } else {
                                            maxRateWads = maxMinRateWads - ((b ** 2) * aInverse) / 4;
                                        }
                                    }
                                    int256 startSlope = maxRateWads / int256(auctionT1); // wad-bips per block
                                    int256 middleSlope = bipsToSignedWads(9000) / int256((3 * auctionDuration) / 5) + 1; // wad-bips per block (add one to account for rounding)
                                    int256 middleB = maxRateWads - int256(auctionT1) * middleSlope;
                                    if (currentAuctionBlock < auctionT1) {
                                        return signedWadsToBips(startSlope * int256(currentAuctionBlock));
                                    } else if (currentAuctionBlock < auctionT2) {
                                        return signedWadsToBips(middleSlope * int256(currentAuctionBlock) + middleB);
                                    } else if (currentAuctionBlock < auctionDuration) {
                                        int256 endSlope;
                                        int256 endB;
                                        {
                                            endSlope =
                                                (bipsToSignedWads(_LIQUIDATION_THRESHOLD) -
                                                    ((int256(auctionT2) * middleSlope) + middleB)) /
                                                int256(auctionDuration - auctionT2); // wad-bips per block
                                            endB =
                                                bipsToSignedWads(_LIQUIDATION_THRESHOLD) -
                                                int256(auctionDuration) *
                                                endSlope;
                                        }
                                        return signedWadsToBips(endSlope * int256(currentAuctionBlock) + endB);
                                    } else {
                                        return _LIQUIDATION_THRESHOLD;
                                    }
                                }
                                /**
                                 * @dev Converts an integer bips value to a signed wad value.
                                 */
                                function bipsToSignedWads(uint256 bips) public pure returns (int256) {
                                    return int256((bips * 1e18) / _BASIS_POINTS);
                                }
                                /**
                                 * @dev Converts a signed wad value to an integer bips value.
                                 */
                                function signedWadsToBips(int256 wads) public pure returns (uint256) {
                                    return uint256((wads * int256(_BASIS_POINTS)) / 1e18);
                                }
                                function executeTakeBid(
                                    Lien calldata lien,
                                    uint256 lienId,
                                    ExecutionV1 calldata execution,
                                    uint256 debt,
                                    IBlurPool pool,
                                    IExchange exchange,
                                    address delegate,
                                    address matchingPolicy
                                ) external {
                                    /* Create sell side order from Blend. */
                                    OrderV1 memory sellOrder = OrderV1({
                                        trader: address(this),
                                        side: Side.Sell,
                                        matchingPolicy: matchingPolicy,
                                        collection: address(lien.collection),
                                        tokenId: lien.tokenId,
                                        amount: 1,
                                        paymentToken: address(pool),
                                        price: execution.makerOrder.order.price,
                                        listingTime: execution.makerOrder.order.listingTime + 1, // listingTime determines maker/taker
                                        expirationTime: type(uint256).max,
                                        fees: new Fee[](0),
                                        salt: lienId, // prevent reused order hash
                                        extraParams: "\\x01" // require oracle signature
                                    });
                                    Input memory sell = Input({
                                        order: sellOrder,
                                        v: 0,
                                        r: bytes32(0),
                                        s: bytes32(0),
                                        extraSignature: execution.extraSignature,
                                        signatureVersion: SignatureVersion.Single,
                                        blockNumber: execution.blockNumber
                                    });
                                    /* Execute marketplace order. */
                                    uint256 balanceBefore = pool.balanceOf(address(this));
                                    lien.collection.approve(delegate, lien.tokenId);
                                    exchange.execute(sell, execution.makerOrder);
                                    /* Determine the funds received from the sale (after fees). */
                                    uint256 amountReceivedFromSale = pool.balanceOf(address(this)) - balanceBefore;
                                    if (amountReceivedFromSale < debt) {
                                        revert InvalidRepayment();
                                    }
                                    /* Repay lender. */
                                    pool.transferFrom(address(this), lien.lender, debt);
                                    /* Send surplus to borrower. */
                                    unchecked {
                                        pool.transferFrom(address(this), lien.borrower, amountReceivedFromSale - debt);
                                    }
                                }
                                function executeTakeAskV2(
                                    LoanOffer calldata offer, 
                                    AskExecutionV2 calldata execution,
                                    uint256 loanAmount,
                                    uint256 collateralTokenId,
                                    uint256 price,
                                    IBlurPool pool,
                                    IExchangeV2 exchangeV2
                                ) external {
                                    OrderV2 calldata order = execution.order;
                                    if (address(offer.collection) != order.collection || order.assetType != AssetType.ERC721) {
                                        revert InvalidExecution();
                                    }
                                    /* Transfer funds. */
                                    /* Need to retrieve the ETH to fund the marketplace execution. */
                                    if (loanAmount < price) {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), loanAmount);
                                        /* Supplement difference from borrower. */
                                        unchecked {
                                            pool.withdrawFrom(msg.sender, address(this), price - loanAmount);
                                        }
                                    } else {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), price);
                                        /* Send surplus to borrower. */
                                        unchecked {
                                            pool.transferFrom(offer.lender, msg.sender, loanAmount - price);
                                        }
                                    }
                                    TakeAskSingle memory execute = TakeAskSingle({
                                        order: execution.order,
                                        exchange: Exchange({
                                            index: 0,
                                            proof: execution.proof,
                                            listing: Listing({
                                                index: execution.listing.index,
                                                tokenId: collateralTokenId,
                                                amount: 1,
                                                price: price
                                            }),
                                            taker: Taker({ tokenId: collateralTokenId, amount: 1 })
                                        }),
                                        takerFee: FeeRate(address(0), 0),
                                        signature: execution.signature,
                                        tokenRecipient: address(this)
                                    });
                                    exchangeV2.takeAskSingle{ value: price }(execute, execution.oracleSignature);
                                }
                                function executeTakeAsk(
                                    LoanOffer calldata offer,
                                    ExecutionV1 calldata execution,
                                    uint256 loanAmount,
                                    uint256 collateralTokenId,
                                    uint256 price,
                                    IBlurPool pool,
                                    IExchange exchange,
                                    address matchingPolicy
                                ) external {
                                    /* Transfer funds. */
                                    /* Need to retrieve the ETH to fund the marketplace execution. */
                                    if (loanAmount < price) {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), loanAmount);
                                        /* Supplement difference from borrower. */
                                        unchecked {
                                            pool.withdrawFrom(msg.sender, address(this), price - loanAmount);
                                        }
                                    } else {
                                        /* Take funds from lender. */
                                        pool.withdrawFrom(offer.lender, address(this), price);
                                        /* Send surplus to borrower. */
                                        unchecked {
                                            pool.transferFrom(offer.lender, msg.sender, loanAmount - price);
                                        }
                                    }
                                    OrderV1 memory buyOrder = OrderV1({
                                        trader: address(this),
                                        side: Side.Buy,
                                        matchingPolicy: matchingPolicy,
                                        collection: address(offer.collection),
                                        tokenId: collateralTokenId,
                                        amount: 1,
                                        paymentToken: address(0),
                                        price: price,
                                        listingTime: execution.makerOrder.order.listingTime + 1, // listingTime determines maker/taker
                                        expirationTime: type(uint256).max,
                                        fees: new Fee[](0),
                                        salt: uint160(execution.makerOrder.order.trader), // prevent reused order hash
                                        extraParams: "\\x01" // require oracle signature
                                    });
                                    Input memory buy = Input({
                                        order: buyOrder,
                                        v: 0,
                                        r: bytes32(0),
                                        s: bytes32(0),
                                        extraSignature: execution.extraSignature,
                                        signatureVersion: SignatureVersion.Single,
                                        blockNumber: execution.blockNumber
                                    });
                                    /* Execute order using ETH currently in contract. */
                                    exchange.execute{ value: price }(execution.makerOrder, buy);
                                }
                                function executeTakeBidV2(
                                    Lien calldata lien,
                                    BidExecutionV2 calldata execution,
                                    uint256 debt,
                                    IBlurPool pool,
                                    IExchangeV2 exchangeV2,
                                    address delegateV2
                                ) external {
                                    OrderV2 calldata order = execution.order;
                                    if (address(lien.collection) != order.collection || order.assetType != AssetType.ERC721) {
                                        revert InvalidExecution();
                                    }
                                    uint256 balanceBefore = pool.balanceOf(address(this));
                                    TakeBidSingle memory execute = TakeBidSingle({
                                        order: execution.order,
                                        exchange: Exchange({
                                            index: 0,
                                            proof: execution.proof,
                                            listing: execution.listing,
                                            taker: Taker({ tokenId: lien.tokenId, amount: 1 })
                                        }),
                                        takerFee: FeeRate(address(0), 0),
                                        signature: execution.signature
                                    });
                                    /* Execute marketplace order. */
                                    lien.collection.approve(delegateV2, lien.tokenId);
                                    exchangeV2.takeBidSingle(execute, execution.oracleSignature);
                                    /* Determine the funds received from the sale (after fees). */
                                    uint256 amountReceivedFromSale = pool.balanceOf(address(this)) - balanceBefore;
                                    if (amountReceivedFromSale < debt) {
                                        revert InvalidRepayment();
                                    }
                                    /* Repay lender. */
                                    pool.transferFrom(address(this), lien.lender, debt);
                                    /* Send surplus to borrower. */
                                    unchecked {
                                        pool.transferFrom(address(this), lien.borrower, amountReceivedFromSale - debt);
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.8.0;
                            /// @notice Signed 18 decimal fixed point (wad) arithmetic library.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SignedWadMath.sol)
                            /// @author Modified from Remco Bloemen (https://xn--2-umb.com/22/exp-ln/index.html)
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            function toWadUnsafe(uint256 x) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 1e18.
                                    r := mul(x, 1000000000000000000)
                                }
                            }
                            /// @dev Takes an integer amount of seconds and converts it to a wad amount of days.
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            /// @dev Not meant for negative second amounts, it assumes x is positive.
                            function toDaysWadUnsafe(uint256 x) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 1e18 and then divide it by 86400.
                                    r := div(mul(x, 1000000000000000000), 86400)
                                }
                            }
                            /// @dev Takes a wad amount of days and converts it to an integer amount of seconds.
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            /// @dev Not meant for negative day amounts, it assumes x is positive.
                            function fromDaysWadUnsafe(int256 x) pure returns (uint256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 86400 and then divide it by 1e18.
                                    r := div(mul(x, 86400), 1000000000000000000)
                                }
                            }
                            /// @dev Will not revert on overflow, only use where overflow is not possible.
                            function unsafeWadMul(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by y and divide by 1e18.
                                    r := sdiv(mul(x, y), 1000000000000000000)
                                }
                            }
                            /// @dev Will return 0 instead of reverting if y is zero and will
                            /// not revert on overflow, only use where overflow is not possible.
                            function unsafeWadDiv(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Multiply x by 1e18 and divide it by y.
                                    r := sdiv(mul(x, 1000000000000000000), y)
                                }
                            }
                            function wadMul(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Store x * y in r for now.
                                    r := mul(x, y)
                                    // Equivalent to require(x == 0 || (x * y) / x == y)
                                    if iszero(or(iszero(x), eq(sdiv(r, x), y))) {
                                        revert(0, 0)
                                    }
                                    // Scale the result down by 1e18.
                                    r := sdiv(r, 1000000000000000000)
                                }
                            }
                            function wadDiv(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Store x * 1e18 in r for now.
                                    r := mul(x, 1000000000000000000)
                                    // Equivalent to require(y != 0 && ((x * 1e18) / 1e18 == x))
                                    if iszero(and(iszero(iszero(y)), eq(sdiv(r, 1000000000000000000), x))) {
                                        revert(0, 0)
                                    }
                                    // Divide r by y.
                                    r := sdiv(r, y)
                                }
                            }
                            /// @dev Will not work with negative bases, only use when x is positive.
                            function wadPow(int256 x, int256 y) pure returns (int256) {
                                // Equivalent to x to the power of y because x ** y = (e ** ln(x)) ** y = e ** (ln(x) * y)
                                return wadExp((wadLn(x) * y) / 1e18); // Using ln(x) means x must be greater than 0.
                            }
                            function wadExp(int256 x) pure returns (int256 r) {
                                unchecked {
                                    // When the result is < 0.5 we return zero. This happens when
                                    // x <= floor(log(0.5e18) * 1e18) ~ -42e18
                                    if (x <= -42139678854452767551) return 0;
                                    // When the result is > (2**255 - 1) / 1e18 we can not represent it as an
                                    // int. This happens when x >= floor(log((2**255 - 1) / 1e18) * 1e18) ~ 135.
                                    if (x >= 135305999368893231589) revert("EXP_OVERFLOW");
                                    // x is now in the range (-42, 136) * 1e18. Convert to (-42, 136) * 2**96
                                    // for more intermediate precision and a binary basis. This base conversion
                                    // is a multiplication by 1e18 / 2**96 = 5**18 / 2**78.
                                    x = (x << 78) / 5**18;
                                    // Reduce range of x to (-½ ln 2, ½ ln 2) * 2**96 by factoring out powers
                                    // of two such that exp(x) = exp(x') * 2**k, where k is an integer.
                                    // Solving this gives k = round(x / log(2)) and x' = x - k * log(2).
                                    int256 k = ((x << 96) / 54916777467707473351141471128 + 2**95) >> 96;
                                    x = x - k * 54916777467707473351141471128;
                                    // k is in the range [-61, 195].
                                    // Evaluate using a (6, 7)-term rational approximation.
                                    // p is made monic, we'll multiply by a scale factor later.
                                    int256 y = x + 1346386616545796478920950773328;
                                    y = ((y * x) >> 96) + 57155421227552351082224309758442;
                                    int256 p = y + x - 94201549194550492254356042504812;
                                    p = ((p * y) >> 96) + 28719021644029726153956944680412240;
                                    p = p * x + (4385272521454847904659076985693276 << 96);
                                    // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                    int256 q = x - 2855989394907223263936484059900;
                                    q = ((q * x) >> 96) + 50020603652535783019961831881945;
                                    q = ((q * x) >> 96) - 533845033583426703283633433725380;
                                    q = ((q * x) >> 96) + 3604857256930695427073651918091429;
                                    q = ((q * x) >> 96) - 14423608567350463180887372962807573;
                                    q = ((q * x) >> 96) + 26449188498355588339934803723976023;
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        // Div in assembly because solidity adds a zero check despite the unchecked.
                                        // The q polynomial won't have zeros in the domain as all its roots are complex.
                                        // No scaling is necessary because p is already 2**96 too large.
                                        r := sdiv(p, q)
                                    }
                                    // r should be in the range (0.09, 0.25) * 2**96.
                                    // We now need to multiply r by:
                                    // * the scale factor s = ~6.031367120.
                                    // * the 2**k factor from the range reduction.
                                    // * the 1e18 / 2**96 factor for base conversion.
                                    // We do this all at once, with an intermediate result in 2**213
                                    // basis, so the final right shift is always by a positive amount.
                                    r = int256((uint256(r) * 3822833074963236453042738258902158003155416615667) >> uint256(195 - k));
                                }
                            }
                            function wadLn(int256 x) pure returns (int256 r) {
                                unchecked {
                                    require(x > 0, "UNDEFINED");
                                    // We want to convert x from 10**18 fixed point to 2**96 fixed point.
                                    // We do this by multiplying by 2**96 / 10**18. But since
                                    // ln(x * C) = ln(x) + ln(C), we can simply do nothing here
                                    // and add ln(2**96 / 10**18) at the end.
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
                                        r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
                                        r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
                                        r := or(r, shl(4, lt(0xffff, shr(r, x))))
                                        r := or(r, shl(3, lt(0xff, shr(r, x))))
                                        r := or(r, shl(2, lt(0xf, shr(r, x))))
                                        r := or(r, shl(1, lt(0x3, shr(r, x))))
                                        r := or(r, lt(0x1, shr(r, x)))
                                    }
                                    // Reduce range of x to (1, 2) * 2**96
                                    // ln(2^k * x) = k * ln(2) + ln(x)
                                    int256 k = r - 96;
                                    x <<= uint256(159 - k);
                                    x = int256(uint256(x) >> 159);
                                    // Evaluate using a (8, 8)-term rational approximation.
                                    // p is made monic, we will multiply by a scale factor later.
                                    int256 p = x + 3273285459638523848632254066296;
                                    p = ((p * x) >> 96) + 24828157081833163892658089445524;
                                    p = ((p * x) >> 96) + 43456485725739037958740375743393;
                                    p = ((p * x) >> 96) - 11111509109440967052023855526967;
                                    p = ((p * x) >> 96) - 45023709667254063763336534515857;
                                    p = ((p * x) >> 96) - 14706773417378608786704636184526;
                                    p = p * x - (795164235651350426258249787498 << 96);
                                    // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                    // q is monic by convention.
                                    int256 q = x + 5573035233440673466300451813936;
                                    q = ((q * x) >> 96) + 71694874799317883764090561454958;
                                    q = ((q * x) >> 96) + 283447036172924575727196451306956;
                                    q = ((q * x) >> 96) + 401686690394027663651624208769553;
                                    q = ((q * x) >> 96) + 204048457590392012362485061816622;
                                    q = ((q * x) >> 96) + 31853899698501571402653359427138;
                                    q = ((q * x) >> 96) + 909429971244387300277376558375;
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        // Div in assembly because solidity adds a zero check despite the unchecked.
                                        // The q polynomial is known not to have zeros in the domain.
                                        // No scaling required because p is already 2**96 too large.
                                        r := sdiv(p, q)
                                    }
                                    // r is in the range (0, 0.125) * 2**96
                                    // Finalization, we need to:
                                    // * multiply by the scale factor s = 5.549…
                                    // * add ln(2**96 / 10**18)
                                    // * add k * ln(2)
                                    // * multiply by 10**18 / 2**96 = 5**18 >> 78
                                    // mul s * 5e18 * 2**96, base is now 5**18 * 2**192
                                    r *= 1677202110996718588342820967067443963516166;
                                    // add ln(2) * k * 5e18 * 2**192
                                    r += 16597577552685614221487285958193947469193820559219878177908093499208371 * k;
                                    // add ln(2**96 / 10**18) * 5e18 * 2**192
                                    r += 600920179829731861736702779321621459595472258049074101567377883020018308;
                                    // base conversion: mul 2**18 / 2**192
                                    r >>= 174;
                                }
                            }
                            /// @dev Will return 0 instead of reverting if y is zero.
                            function unsafeDiv(int256 x, int256 y) pure returns (int256 r) {
                                /// @solidity memory-safe-assembly
                                assembly {
                                    // Divide x by y.
                                    r := sdiv(x, y)
                                }
                            }
                            // SPDX-License-Identifier: BSL 1.1 - Blend (c) Non Fungible Trading Ltd.
                            pragma solidity 0.8.17;
                            // Blend
                            error Unauthorized();
                            error InvalidLoan();
                            error InvalidLien();
                            error InsufficientOffer();
                            error InvalidRepayment();
                            error LienIsDefaulted();
                            error LienNotDefaulted();
                            error AuctionIsActive();
                            error AuctionIsNotActive();
                            error InvalidRefinance();
                            error RateTooHigh();
                            error FeesTooHigh();
                            error CollectionsDoNotMatch();
                            error InvalidAuctionDuration();
                            // OfferController
                            error OfferExpired();
                            error OfferUnavailable();
                            // Signatures
                            error UnauthorizedOracle();
                            error SignatureExpired();
                            error InvalidSignature();
                            error InvalidVParameter();
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            import "lib/solmate/src/tokens/ERC721.sol";
                            import { Input, Fee } from "../../exchangeV1/lib/OrderStructs.sol";
                            import { Order as OrderV2, Listing } from "../../exchangeV2/lib/Structs.sol";
                            struct LienPointer {
                                Lien lien;
                                uint256 lienId;
                            }
                            struct SellOffer {
                                address borrower;
                                uint256 lienId;
                                uint256 price;
                                uint256 expirationTime;
                                uint256 salt;
                                address oracle;
                                Fee[] fees;
                            }
                            struct Lien {
                                address lender;
                                address borrower;
                                ERC721 collection;
                                uint256 tokenId;
                                uint256 amount;
                                uint256 startTime;
                                uint256 rate;
                                uint256 auctionStartBlock;
                                uint256 auctionDuration;
                            }
                            struct LoanOffer {
                                address lender;
                                ERC721 collection;
                                uint256 totalAmount;
                                uint256 minAmount;
                                uint256 maxAmount;
                                uint256 auctionDuration;
                                uint256 salt;
                                uint256 expirationTime;
                                uint256 rate;
                                address oracle;
                            }
                            struct LoanInput {
                                LoanOffer offer;
                                bytes signature;
                            }
                            struct SellInput {
                                SellOffer offer;
                                bytes signature;
                            }
                            struct ExecutionV1 {
                                Input makerOrder;
                                bytes extraSignature;
                                uint256 blockNumber;
                            }
                            struct BidExecutionV2 {
                                OrderV2 order;
                                Listing listing;
                                bytes32[] proof;
                                bytes signature;
                                bytes oracleSignature;
                            }
                            struct AskExecutionV2 {
                                OrderV2 order;
                                Listing listing;
                                bytes32[] proof;
                                bytes signature;
                                bytes oracleSignature;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            interface IBlurPool {
                                event Transfer(address indexed from, address indexed to, uint256 amount);
                                function initialize() external;
                                function decimals() external pure returns (uint8);
                                function totalSupply() external view returns (uint256);
                                function balanceOf(address user) external view returns (uint256);
                                function deposit() external payable;
                                function deposit(address user) external payable;
                                function withdraw(uint256 amount) external;
                                function withdrawFrom(address from, address to, uint256 amount) external;
                                function transferFrom(address from, address to, uint256 amount) external returns (bool);
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            import {
                                TakeAsk,
                                TakeBid,
                                TakeAskSingle,
                                TakeBidSingle,
                                Order,
                                Exchange,
                                Fees,
                                FeeRate,
                                AssetType,
                                OrderType,
                                Transfer,
                                FungibleTransfers,
                                StateUpdate,
                                Cancel,
                                Listing
                            } from "../lib/Structs.sol";
                            interface IBlurExchangeV2 {
                                error InsufficientFunds();
                                error TokenTransferFailed();
                                error InvalidOrder();
                                error ProtocolFeeTooHigh();
                                event NewProtocolFee(address indexed recipient, uint16 indexed rate);
                                event NewGovernor(address indexed governor);
                                event NewBlockRange(uint256 blockRange);
                                event CancelTrade(address indexed user, bytes32 hash, uint256 index, uint256 amount);
                                event NonceIncremented(address indexed user, uint256 newNonce);
                                event SetOracle(address indexed user, bool approved);
                                function initialize() external;
                                function setProtocolFee(address recipient, uint16 rate) external;
                                function setGovernor(address _governor) external;
                                function setOracle(address oracle, bool approved) external;
                                function setBlockRange(uint256 _blockRange) external;
                                function cancelTrades(Cancel[] memory cancels) external;
                                function incrementNonce() external;
                                /*//////////////////////////////////////////////////////////////
                                                      EXECUTION WRAPPERS
                                //////////////////////////////////////////////////////////////*/
                                function takeAsk(TakeAsk memory inputs, bytes calldata oracleSignature) external payable;
                                function takeBid(TakeBid memory inputs, bytes calldata oracleSignature) external;
                                function takeAskSingle(TakeAskSingle memory inputs, bytes calldata oracleSignature) external payable;
                                function takeBidSingle(TakeBidSingle memory inputs, bytes calldata oracleSignature) external;
                                /*//////////////////////////////////////////////////////////////
                                                    EXECUTION POOL WRAPPERS
                                //////////////////////////////////////////////////////////////*/
                                function takeAskSinglePool(
                                    TakeAskSingle memory inputs,
                                    bytes calldata oracleSignature,
                                    uint256 amountToWithdraw
                                ) external payable;
                                function takeAskPool(
                                    TakeAsk memory inputs,
                                    bytes calldata oracleSignature,
                                    uint256 amountToWithdraw
                                ) external payable;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            enum Side { Buy, Sell }
                            enum SignatureVersion { Single, Bulk }
                            enum AssetType { ERC721, ERC1155 }
                            struct Fee {
                                uint16 rate;
                                address payable recipient;
                            }
                            struct Order {
                                address trader;
                                Side side;
                                address matchingPolicy;
                                address collection;
                                uint256 tokenId;
                                uint256 amount;
                                address paymentToken;
                                uint256 price;
                                uint256 listingTime;
                                /* Order expiration timestamp - 0 for oracle cancellations. */
                                uint256 expirationTime;
                                Fee[] fees;
                                uint256 salt;
                                bytes extraParams;
                            }
                            struct Input {
                                Order order;
                                uint8 v;
                                bytes32 r;
                                bytes32 s;
                                bytes extraSignature;
                                SignatureVersion signatureVersion;
                                uint256 blockNumber;
                            }
                            struct Execution {
                              Input sell;
                              Input buy;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.17;
                            struct TakeAsk {
                                Order[] orders;
                                Exchange[] exchanges;
                                FeeRate takerFee;
                                bytes signatures;
                                address tokenRecipient;
                            }
                            struct TakeAskSingle {
                                Order order;
                                Exchange exchange;
                                FeeRate takerFee;
                                bytes signature;
                                address tokenRecipient;
                            }
                            struct TakeBid {
                                Order[] orders;
                                Exchange[] exchanges;
                                FeeRate takerFee;
                                bytes signatures;
                            }
                            struct TakeBidSingle {
                                Order order;
                                Exchange exchange;
                                FeeRate takerFee;
                                bytes signature;
                            }
                            enum AssetType {
                                ERC721,
                                ERC1155
                            }
                            enum OrderType {
                                ASK,
                                BID
                            }
                            struct Exchange { // Size: 0x80
                                uint256 index; // 0x00
                                bytes32[] proof; // 0x20
                                Listing listing; // 0x40
                                Taker taker; // 0x60
                            }
                            struct Listing { // Size: 0x80
                                uint256 index; // 0x00
                                uint256 tokenId; // 0x20
                                uint256 amount; // 0x40
                                uint256 price; // 0x60
                            }
                            struct Taker { // Size: 0x40
                                uint256 tokenId; // 0x00
                                uint256 amount; // 0x20
                            }
                            struct Order { // Size: 0x100
                                address trader; // 0x00
                                address collection; // 0x20
                                bytes32 listingsRoot; // 0x40
                                uint256 numberOfListings; // 0x60
                                uint256 expirationTime; // 0x80
                                AssetType assetType; // 0xa0
                                FeeRate makerFee; // 0xc0
                                uint256 salt; // 0xe0
                            }
                            /*
                            Reference only; struct is composed manually using calldata formatting in execution
                            struct ExecutionBatch { // Size: 0x80
                                address taker; // 0x00
                                OrderType orderType; // 0x20
                                Transfer[] transfers; // 0x40
                                uint256 length; // 0x60
                            }
                            */
                            struct Transfer { // Size: 0xa0
                                address trader; // 0x00
                                uint256 id; // 0x20
                                uint256 amount; // 0x40
                                address collection; // 0x60
                                AssetType assetType; // 0x80
                            }
                            struct FungibleTransfers {
                                uint256 totalProtocolFee;
                                uint256 totalSellerTransfer;
                                uint256 totalTakerFee;
                                uint256 feeRecipientId;
                                uint256 makerId;
                                address[] feeRecipients;
                                address[] makers;
                                uint256[] makerTransfers;
                                uint256[] feeTransfers;
                                AtomicExecution[] executions;
                            }
                            struct AtomicExecution { // Size: 0xe0
                                uint256 makerId; // 0x00
                                uint256 sellerAmount; // 0x20
                                uint256 makerFeeRecipientId; // 0x40
                                uint256 makerFeeAmount; // 0x60
                                uint256 takerFeeAmount; // 0x80
                                uint256 protocolFeeAmount; // 0xa0
                                StateUpdate stateUpdate; // 0xc0
                            }
                            struct StateUpdate { // Size: 0xa0
                                address trader; // 0x00
                                bytes32 hash; // 0x20
                                uint256 index; // 0x40
                                uint256 value; // 0x60
                                uint256 maxAmount; // 0x80
                            }
                            struct Fees { // Size: 0x40
                                FeeRate protocolFee; // 0x00
                                FeeRate takerFee; // 0x20
                            }
                            struct FeeRate { // Size: 0x40
                                address recipient; // 0x00
                                uint16 rate; // 0x20
                            }
                            struct Cancel {
                                bytes32 hash;
                                uint256 index;
                                uint256 amount;
                            }
                            // SPDX-License-Identifier: AGPL-3.0-only
                            pragma solidity >=0.8.0;
                            /// @notice Modern, minimalist, and gas efficient ERC-721 implementation.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
                            abstract contract ERC721 {
                                /*//////////////////////////////////////////////////////////////
                                                             EVENTS
                                //////////////////////////////////////////////////////////////*/
                                event Transfer(address indexed from, address indexed to, uint256 indexed id);
                                event Approval(address indexed owner, address indexed spender, uint256 indexed id);
                                event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
                                /*//////////////////////////////////////////////////////////////
                                                     METADATA STORAGE/LOGIC
                                //////////////////////////////////////////////////////////////*/
                                string public name;
                                string public symbol;
                                function tokenURI(uint256 id) public view virtual returns (string memory);
                                /*//////////////////////////////////////////////////////////////
                                                  ERC721 BALANCE/OWNER STORAGE
                                //////////////////////////////////////////////////////////////*/
                                mapping(uint256 => address) internal _ownerOf;
                                mapping(address => uint256) internal _balanceOf;
                                function ownerOf(uint256 id) public view virtual returns (address owner) {
                                    require((owner = _ownerOf[id]) != address(0), "NOT_MINTED");
                                }
                                function balanceOf(address owner) public view virtual returns (uint256) {
                                    require(owner != address(0), "ZERO_ADDRESS");
                                    return _balanceOf[owner];
                                }
                                /*//////////////////////////////////////////////////////////////
                                                     ERC721 APPROVAL STORAGE
                                //////////////////////////////////////////////////////////////*/
                                mapping(uint256 => address) public getApproved;
                                mapping(address => mapping(address => bool)) public isApprovedForAll;
                                /*//////////////////////////////////////////////////////////////
                                                           CONSTRUCTOR
                                //////////////////////////////////////////////////////////////*/
                                constructor(string memory _name, string memory _symbol) {
                                    name = _name;
                                    symbol = _symbol;
                                }
                                /*//////////////////////////////////////////////////////////////
                                                          ERC721 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function approve(address spender, uint256 id) public virtual {
                                    address owner = _ownerOf[id];
                                    require(msg.sender == owner || isApprovedForAll[owner][msg.sender], "NOT_AUTHORIZED");
                                    getApproved[id] = spender;
                                    emit Approval(owner, spender, id);
                                }
                                function setApprovalForAll(address operator, bool approved) public virtual {
                                    isApprovedForAll[msg.sender][operator] = approved;
                                    emit ApprovalForAll(msg.sender, operator, approved);
                                }
                                function transferFrom(
                                    address from,
                                    address to,
                                    uint256 id
                                ) public virtual {
                                    require(from == _ownerOf[id], "WRONG_FROM");
                                    require(to != address(0), "INVALID_RECIPIENT");
                                    require(
                                        msg.sender == from || isApprovedForAll[from][msg.sender] || msg.sender == getApproved[id],
                                        "NOT_AUTHORIZED"
                                    );
                                    // Underflow of the sender's balance is impossible because we check for
                                    // ownership above and the recipient's balance can't realistically overflow.
                                    unchecked {
                                        _balanceOf[from]--;
                                        _balanceOf[to]++;
                                    }
                                    _ownerOf[id] = to;
                                    delete getApproved[id];
                                    emit Transfer(from, to, id);
                                }
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 id
                                ) public virtual {
                                    transferFrom(from, to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, "") ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 id,
                                    bytes calldata data
                                ) public virtual {
                                    transferFrom(from, to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, data) ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                /*//////////////////////////////////////////////////////////////
                                                          ERC165 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
                                    return
                                        interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
                                        interfaceId == 0x80ac58cd || // ERC165 Interface ID for ERC721
                                        interfaceId == 0x5b5e139f; // ERC165 Interface ID for ERC721Metadata
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL MINT/BURN LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _mint(address to, uint256 id) internal virtual {
                                    require(to != address(0), "INVALID_RECIPIENT");
                                    require(_ownerOf[id] == address(0), "ALREADY_MINTED");
                                    // Counter overflow is incredibly unrealistic.
                                    unchecked {
                                        _balanceOf[to]++;
                                    }
                                    _ownerOf[id] = to;
                                    emit Transfer(address(0), to, id);
                                }
                                function _burn(uint256 id) internal virtual {
                                    address owner = _ownerOf[id];
                                    require(owner != address(0), "NOT_MINTED");
                                    // Ownership check above ensures no underflow.
                                    unchecked {
                                        _balanceOf[owner]--;
                                    }
                                    delete _ownerOf[id];
                                    delete getApproved[id];
                                    emit Transfer(owner, address(0), id);
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL SAFE MINT LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _safeMint(address to, uint256 id) internal virtual {
                                    _mint(to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, "") ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function _safeMint(
                                    address to,
                                    uint256 id,
                                    bytes memory data
                                ) internal virtual {
                                    _mint(to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, data) ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                            }
                            /// @notice A generic interface for a contract which properly accepts ERC721 tokens.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
                            abstract contract ERC721TokenReceiver {
                                function onERC721Received(
                                    address,
                                    address,
                                    uint256,
                                    bytes calldata
                                ) external virtual returns (bytes4) {
                                    return ERC721TokenReceiver.onERC721Received.selector;
                                }
                            }
                            

                            File 6 of 6: Delegate
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            import { ERC721 } from "lib/solmate/src/tokens/ERC721.sol";
                            import { ERC1155 } from "lib/solmate/src/tokens/ERC1155.sol";
                            import { ERC20 } from "lib/solmate/src/tokens/ERC20.sol";
                            import "./lib/Constants.sol";
                            import { AssetType, OrderType, Transfer } from "./lib/Structs.sol";
                            contract Delegate {
                                error Unauthorized();
                                error InvalidLength();
                                address private immutable _EXCHANGE;
                                constructor(address exchange) {
                                    _EXCHANGE = exchange;
                                }
                                modifier onlyApproved() {
                                    if (msg.sender != _EXCHANGE) {
                                        revert Unauthorized();
                                    }
                                    _;
                                }
                                function transfer(
                                    address taker,
                                    OrderType orderType,
                                    Transfer[] calldata transfers,
                                    uint256 length
                                ) external onlyApproved returns (bool[] memory successful) {
                                    if (transfers.length < length) {
                                        revert InvalidLength();
                                    }
                                    successful = new bool[](length);
                                    for (uint256 i; i < length; ) {
                                        assembly {
                                            let calldataPointer := mload(0x40)
                                            let transfersPointer := add(transfers.offset, mul(Transfer_size, i))
                                            let assetType := calldataload(add(transfersPointer, Transfer_assetType_offset))
                                            switch assetType
                                            case 0 {
                                                // AssetType_ERC721
                                                mstore(calldataPointer, ERC721_safeTransferFrom_selector)
                                                switch orderType
                                                case 0 {
                                                    // OrderType_ASK; taker is recipient
                                                    mstore(add(calldataPointer, ERC721_safeTransferFrom_to_offset), taker)
                                                    mstore(
                                                        add(calldataPointer, ERC721_safeTransferFrom_from_offset),
                                                        calldataload(add(transfersPointer, Transfer_trader_offset))
                                                    )
                                                }
                                                case 1 {
                                                    // OrderType_BID; taker is sender
                                                    mstore(add(calldataPointer, ERC721_safeTransferFrom_from_offset), taker)
                                                    mstore(
                                                        add(calldataPointer, ERC721_safeTransferFrom_to_offset),
                                                        calldataload(add(transfersPointer, Transfer_trader_offset))
                                                    )
                                                }
                                                default {
                                                    revert(0, 0)
                                                }
                                                mstore(
                                                    add(calldataPointer, ERC721_safeTransferFrom_id_offset),
                                                    calldataload(add(transfersPointer, Transfer_id_offset))
                                                )
                                                let collection := calldataload(
                                                    add(transfersPointer, Transfer_collection_offset)
                                                )
                                                let success := call(
                                                    gas(),
                                                    collection,
                                                    0,
                                                    calldataPointer,
                                                    ERC721_safeTransferFrom_size,
                                                    0,
                                                    0
                                                )
                                                mstore(add(add(successful, 0x20), mul(0x20, i)), success)
                                            }
                                            case 1 {
                                                // AssetType_ERC1155
                                                mstore(calldataPointer, ERC1155_safeTransferFrom_selector)
                                                switch orderType
                                                case 0 {
                                                    // OrderType_ASK; taker is recipient
                                                    mstore(
                                                        add(calldataPointer, ERC1155_safeTransferFrom_from_offset),
                                                        calldataload(
                                                            add(
                                                                transfersPointer,
                                                                Transfer_trader_offset
                                                            )
                                                        )
                                                    )
                                                    mstore(add(calldataPointer, ERC1155_safeTransferFrom_to_offset), taker)
                                                }
                                                case 1 {
                                                    // OrderType_BID; taker is sender
                                                    mstore(
                                                        add(calldataPointer, ERC1155_safeTransferFrom_to_offset),
                                                        calldataload(
                                                            add(
                                                                transfersPointer,
                                                                Transfer_trader_offset
                                                            )
                                                        )
                                                    )
                                                    mstore(add(calldataPointer, ERC1155_safeTransferFrom_from_offset), taker)
                                                }
                                                default {
                                                    revert(0, 0)
                                                }
                                                mstore(add(calldataPointer, ERC1155_safeTransferFrom_data_pointer_offset), 0xa0)
                                                mstore(add(calldataPointer, ERC1155_safeTransferFrom_data_offset), 0)
                                                mstore(
                                                    add(calldataPointer, ERC1155_safeTransferFrom_id_offset),
                                                    calldataload(
                                                        add(transfersPointer, Transfer_id_offset)
                                                    )
                                                )
                                                mstore(
                                                    add(calldataPointer, ERC1155_safeTransferFrom_amount_offset),
                                                    calldataload(
                                                        add(
                                                            transfersPointer,
                                                            Transfer_amount_offset
                                                        )
                                                    )
                                                )
                                                let collection := calldataload(
                                                    add(
                                                        transfersPointer,
                                                        Transfer_collection_offset
                                                    )
                                                )
                                                let success := call(
                                                    gas(),
                                                    collection,
                                                    0,
                                                    calldataPointer,
                                                    ERC1155_safeTransferFrom_size,
                                                    0,
                                                    0
                                                )
                                                mstore(add(add(successful, 0x20), mul(0x20, i)), success)
                                            }
                                            default {
                                                revert(0, 0)
                                            }
                                        }
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                }
                            }
                            // SPDX-License-Identifier: AGPL-3.0-only
                            pragma solidity >=0.8.0;
                            /// @notice Modern, minimalist, and gas efficient ERC-721 implementation.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
                            abstract contract ERC721 {
                                /*//////////////////////////////////////////////////////////////
                                                             EVENTS
                                //////////////////////////////////////////////////////////////*/
                                event Transfer(address indexed from, address indexed to, uint256 indexed id);
                                event Approval(address indexed owner, address indexed spender, uint256 indexed id);
                                event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
                                /*//////////////////////////////////////////////////////////////
                                                     METADATA STORAGE/LOGIC
                                //////////////////////////////////////////////////////////////*/
                                string public name;
                                string public symbol;
                                function tokenURI(uint256 id) public view virtual returns (string memory);
                                /*//////////////////////////////////////////////////////////////
                                                  ERC721 BALANCE/OWNER STORAGE
                                //////////////////////////////////////////////////////////////*/
                                mapping(uint256 => address) internal _ownerOf;
                                mapping(address => uint256) internal _balanceOf;
                                function ownerOf(uint256 id) public view virtual returns (address owner) {
                                    require((owner = _ownerOf[id]) != address(0), "NOT_MINTED");
                                }
                                function balanceOf(address owner) public view virtual returns (uint256) {
                                    require(owner != address(0), "ZERO_ADDRESS");
                                    return _balanceOf[owner];
                                }
                                /*//////////////////////////////////////////////////////////////
                                                     ERC721 APPROVAL STORAGE
                                //////////////////////////////////////////////////////////////*/
                                mapping(uint256 => address) public getApproved;
                                mapping(address => mapping(address => bool)) public isApprovedForAll;
                                /*//////////////////////////////////////////////////////////////
                                                           CONSTRUCTOR
                                //////////////////////////////////////////////////////////////*/
                                constructor(string memory _name, string memory _symbol) {
                                    name = _name;
                                    symbol = _symbol;
                                }
                                /*//////////////////////////////////////////////////////////////
                                                          ERC721 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function approve(address spender, uint256 id) public virtual {
                                    address owner = _ownerOf[id];
                                    require(msg.sender == owner || isApprovedForAll[owner][msg.sender], "NOT_AUTHORIZED");
                                    getApproved[id] = spender;
                                    emit Approval(owner, spender, id);
                                }
                                function setApprovalForAll(address operator, bool approved) public virtual {
                                    isApprovedForAll[msg.sender][operator] = approved;
                                    emit ApprovalForAll(msg.sender, operator, approved);
                                }
                                function transferFrom(
                                    address from,
                                    address to,
                                    uint256 id
                                ) public virtual {
                                    require(from == _ownerOf[id], "WRONG_FROM");
                                    require(to != address(0), "INVALID_RECIPIENT");
                                    require(
                                        msg.sender == from || isApprovedForAll[from][msg.sender] || msg.sender == getApproved[id],
                                        "NOT_AUTHORIZED"
                                    );
                                    // Underflow of the sender's balance is impossible because we check for
                                    // ownership above and the recipient's balance can't realistically overflow.
                                    unchecked {
                                        _balanceOf[from]--;
                                        _balanceOf[to]++;
                                    }
                                    _ownerOf[id] = to;
                                    delete getApproved[id];
                                    emit Transfer(from, to, id);
                                }
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 id
                                ) public virtual {
                                    transferFrom(from, to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, "") ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 id,
                                    bytes calldata data
                                ) public virtual {
                                    transferFrom(from, to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, data) ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                /*//////////////////////////////////////////////////////////////
                                                          ERC165 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
                                    return
                                        interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
                                        interfaceId == 0x80ac58cd || // ERC165 Interface ID for ERC721
                                        interfaceId == 0x5b5e139f; // ERC165 Interface ID for ERC721Metadata
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL MINT/BURN LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _mint(address to, uint256 id) internal virtual {
                                    require(to != address(0), "INVALID_RECIPIENT");
                                    require(_ownerOf[id] == address(0), "ALREADY_MINTED");
                                    // Counter overflow is incredibly unrealistic.
                                    unchecked {
                                        _balanceOf[to]++;
                                    }
                                    _ownerOf[id] = to;
                                    emit Transfer(address(0), to, id);
                                }
                                function _burn(uint256 id) internal virtual {
                                    address owner = _ownerOf[id];
                                    require(owner != address(0), "NOT_MINTED");
                                    // Ownership check above ensures no underflow.
                                    unchecked {
                                        _balanceOf[owner]--;
                                    }
                                    delete _ownerOf[id];
                                    delete getApproved[id];
                                    emit Transfer(owner, address(0), id);
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL SAFE MINT LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _safeMint(address to, uint256 id) internal virtual {
                                    _mint(to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, "") ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function _safeMint(
                                    address to,
                                    uint256 id,
                                    bytes memory data
                                ) internal virtual {
                                    _mint(to, id);
                                    require(
                                        to.code.length == 0 ||
                                            ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, data) ==
                                            ERC721TokenReceiver.onERC721Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                            }
                            /// @notice A generic interface for a contract which properly accepts ERC721 tokens.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
                            abstract contract ERC721TokenReceiver {
                                function onERC721Received(
                                    address,
                                    address,
                                    uint256,
                                    bytes calldata
                                ) external virtual returns (bytes4) {
                                    return ERC721TokenReceiver.onERC721Received.selector;
                                }
                            }
                            // SPDX-License-Identifier: AGPL-3.0-only
                            pragma solidity >=0.8.0;
                            /// @notice Minimalist and gas efficient standard ERC1155 implementation.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC1155.sol)
                            abstract contract ERC1155 {
                                /*//////////////////////////////////////////////////////////////
                                                             EVENTS
                                //////////////////////////////////////////////////////////////*/
                                event TransferSingle(
                                    address indexed operator,
                                    address indexed from,
                                    address indexed to,
                                    uint256 id,
                                    uint256 amount
                                );
                                event TransferBatch(
                                    address indexed operator,
                                    address indexed from,
                                    address indexed to,
                                    uint256[] ids,
                                    uint256[] amounts
                                );
                                event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
                                event URI(string value, uint256 indexed id);
                                /*//////////////////////////////////////////////////////////////
                                                         ERC1155 STORAGE
                                //////////////////////////////////////////////////////////////*/
                                mapping(address => mapping(uint256 => uint256)) public balanceOf;
                                mapping(address => mapping(address => bool)) public isApprovedForAll;
                                /*//////////////////////////////////////////////////////////////
                                                         METADATA LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function uri(uint256 id) public view virtual returns (string memory);
                                /*//////////////////////////////////////////////////////////////
                                                          ERC1155 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function setApprovalForAll(address operator, bool approved) public virtual {
                                    isApprovedForAll[msg.sender][operator] = approved;
                                    emit ApprovalForAll(msg.sender, operator, approved);
                                }
                                function safeTransferFrom(
                                    address from,
                                    address to,
                                    uint256 id,
                                    uint256 amount,
                                    bytes calldata data
                                ) public virtual {
                                    require(msg.sender == from || isApprovedForAll[from][msg.sender], "NOT_AUTHORIZED");
                                    balanceOf[from][id] -= amount;
                                    balanceOf[to][id] += amount;
                                    emit TransferSingle(msg.sender, from, to, id, amount);
                                    require(
                                        to.code.length == 0
                                            ? to != address(0)
                                            : ERC1155TokenReceiver(to).onERC1155Received(msg.sender, from, id, amount, data) ==
                                                ERC1155TokenReceiver.onERC1155Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function safeBatchTransferFrom(
                                    address from,
                                    address to,
                                    uint256[] calldata ids,
                                    uint256[] calldata amounts,
                                    bytes calldata data
                                ) public virtual {
                                    require(ids.length == amounts.length, "LENGTH_MISMATCH");
                                    require(msg.sender == from || isApprovedForAll[from][msg.sender], "NOT_AUTHORIZED");
                                    // Storing these outside the loop saves ~15 gas per iteration.
                                    uint256 id;
                                    uint256 amount;
                                    for (uint256 i = 0; i < ids.length; ) {
                                        id = ids[i];
                                        amount = amounts[i];
                                        balanceOf[from][id] -= amount;
                                        balanceOf[to][id] += amount;
                                        // An array can't have a total length
                                        // larger than the max uint256 value.
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                    emit TransferBatch(msg.sender, from, to, ids, amounts);
                                    require(
                                        to.code.length == 0
                                            ? to != address(0)
                                            : ERC1155TokenReceiver(to).onERC1155BatchReceived(msg.sender, from, ids, amounts, data) ==
                                                ERC1155TokenReceiver.onERC1155BatchReceived.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function balanceOfBatch(address[] calldata owners, uint256[] calldata ids)
                                    public
                                    view
                                    virtual
                                    returns (uint256[] memory balances)
                                {
                                    require(owners.length == ids.length, "LENGTH_MISMATCH");
                                    balances = new uint256[](owners.length);
                                    // Unchecked because the only math done is incrementing
                                    // the array index counter which cannot possibly overflow.
                                    unchecked {
                                        for (uint256 i = 0; i < owners.length; ++i) {
                                            balances[i] = balanceOf[owners[i]][ids[i]];
                                        }
                                    }
                                }
                                /*//////////////////////////////////////////////////////////////
                                                          ERC165 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
                                    return
                                        interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
                                        interfaceId == 0xd9b67a26 || // ERC165 Interface ID for ERC1155
                                        interfaceId == 0x0e89341c; // ERC165 Interface ID for ERC1155MetadataURI
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL MINT/BURN LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _mint(
                                    address to,
                                    uint256 id,
                                    uint256 amount,
                                    bytes memory data
                                ) internal virtual {
                                    balanceOf[to][id] += amount;
                                    emit TransferSingle(msg.sender, address(0), to, id, amount);
                                    require(
                                        to.code.length == 0
                                            ? to != address(0)
                                            : ERC1155TokenReceiver(to).onERC1155Received(msg.sender, address(0), id, amount, data) ==
                                                ERC1155TokenReceiver.onERC1155Received.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function _batchMint(
                                    address to,
                                    uint256[] memory ids,
                                    uint256[] memory amounts,
                                    bytes memory data
                                ) internal virtual {
                                    uint256 idsLength = ids.length; // Saves MLOADs.
                                    require(idsLength == amounts.length, "LENGTH_MISMATCH");
                                    for (uint256 i = 0; i < idsLength; ) {
                                        balanceOf[to][ids[i]] += amounts[i];
                                        // An array can't have a total length
                                        // larger than the max uint256 value.
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                    emit TransferBatch(msg.sender, address(0), to, ids, amounts);
                                    require(
                                        to.code.length == 0
                                            ? to != address(0)
                                            : ERC1155TokenReceiver(to).onERC1155BatchReceived(msg.sender, address(0), ids, amounts, data) ==
                                                ERC1155TokenReceiver.onERC1155BatchReceived.selector,
                                        "UNSAFE_RECIPIENT"
                                    );
                                }
                                function _batchBurn(
                                    address from,
                                    uint256[] memory ids,
                                    uint256[] memory amounts
                                ) internal virtual {
                                    uint256 idsLength = ids.length; // Saves MLOADs.
                                    require(idsLength == amounts.length, "LENGTH_MISMATCH");
                                    for (uint256 i = 0; i < idsLength; ) {
                                        balanceOf[from][ids[i]] -= amounts[i];
                                        // An array can't have a total length
                                        // larger than the max uint256 value.
                                        unchecked {
                                            ++i;
                                        }
                                    }
                                    emit TransferBatch(msg.sender, from, address(0), ids, amounts);
                                }
                                function _burn(
                                    address from,
                                    uint256 id,
                                    uint256 amount
                                ) internal virtual {
                                    balanceOf[from][id] -= amount;
                                    emit TransferSingle(msg.sender, from, address(0), id, amount);
                                }
                            }
                            /// @notice A generic interface for a contract which properly accepts ERC1155 tokens.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC1155.sol)
                            abstract contract ERC1155TokenReceiver {
                                function onERC1155Received(
                                    address,
                                    address,
                                    uint256,
                                    uint256,
                                    bytes calldata
                                ) external virtual returns (bytes4) {
                                    return ERC1155TokenReceiver.onERC1155Received.selector;
                                }
                                function onERC1155BatchReceived(
                                    address,
                                    address,
                                    uint256[] calldata,
                                    uint256[] calldata,
                                    bytes calldata
                                ) external virtual returns (bytes4) {
                                    return ERC1155TokenReceiver.onERC1155BatchReceived.selector;
                                }
                            }
                            // SPDX-License-Identifier: AGPL-3.0-only
                            pragma solidity >=0.8.0;
                            /// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
                            /// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
                            /// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
                            /// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
                            abstract contract ERC20 {
                                /*//////////////////////////////////////////////////////////////
                                                             EVENTS
                                //////////////////////////////////////////////////////////////*/
                                event Transfer(address indexed from, address indexed to, uint256 amount);
                                event Approval(address indexed owner, address indexed spender, uint256 amount);
                                /*//////////////////////////////////////////////////////////////
                                                        METADATA STORAGE
                                //////////////////////////////////////////////////////////////*/
                                string public name;
                                string public symbol;
                                uint8 public immutable decimals;
                                /*//////////////////////////////////////////////////////////////
                                                          ERC20 STORAGE
                                //////////////////////////////////////////////////////////////*/
                                uint256 public totalSupply;
                                mapping(address => uint256) public balanceOf;
                                mapping(address => mapping(address => uint256)) public allowance;
                                /*//////////////////////////////////////////////////////////////
                                                        EIP-2612 STORAGE
                                //////////////////////////////////////////////////////////////*/
                                uint256 internal immutable INITIAL_CHAIN_ID;
                                bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
                                mapping(address => uint256) public nonces;
                                /*//////////////////////////////////////////////////////////////
                                                           CONSTRUCTOR
                                //////////////////////////////////////////////////////////////*/
                                constructor(
                                    string memory _name,
                                    string memory _symbol,
                                    uint8 _decimals
                                ) {
                                    name = _name;
                                    symbol = _symbol;
                                    decimals = _decimals;
                                    INITIAL_CHAIN_ID = block.chainid;
                                    INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
                                }
                                /*//////////////////////////////////////////////////////////////
                                                           ERC20 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function approve(address spender, uint256 amount) public virtual returns (bool) {
                                    allowance[msg.sender][spender] = amount;
                                    emit Approval(msg.sender, spender, amount);
                                    return true;
                                }
                                function transfer(address to, uint256 amount) public virtual returns (bool) {
                                    balanceOf[msg.sender] -= amount;
                                    // Cannot overflow because the sum of all user
                                    // balances can't exceed the max uint256 value.
                                    unchecked {
                                        balanceOf[to] += amount;
                                    }
                                    emit Transfer(msg.sender, to, amount);
                                    return true;
                                }
                                function transferFrom(
                                    address from,
                                    address to,
                                    uint256 amount
                                ) public virtual returns (bool) {
                                    uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.
                                    if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;
                                    balanceOf[from] -= amount;
                                    // Cannot overflow because the sum of all user
                                    // balances can't exceed the max uint256 value.
                                    unchecked {
                                        balanceOf[to] += amount;
                                    }
                                    emit Transfer(from, to, amount);
                                    return true;
                                }
                                /*//////////////////////////////////////////////////////////////
                                                         EIP-2612 LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function permit(
                                    address owner,
                                    address spender,
                                    uint256 value,
                                    uint256 deadline,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) public virtual {
                                    require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");
                                    // Unchecked because the only math done is incrementing
                                    // the owner's nonce which cannot realistically overflow.
                                    unchecked {
                                        address recoveredAddress = ecrecover(
                                            keccak256(
                                                abi.encodePacked(
                                                    "\\x19\\x01",
                                                    DOMAIN_SEPARATOR(),
                                                    keccak256(
                                                        abi.encode(
                                                            keccak256(
                                                                "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                                            ),
                                                            owner,
                                                            spender,
                                                            value,
                                                            nonces[owner]++,
                                                            deadline
                                                        )
                                                    )
                                                )
                                            ),
                                            v,
                                            r,
                                            s
                                        );
                                        require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");
                                        allowance[recoveredAddress][spender] = value;
                                    }
                                    emit Approval(owner, spender, value);
                                }
                                function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
                                    return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
                                }
                                function computeDomainSeparator() internal view virtual returns (bytes32) {
                                    return
                                        keccak256(
                                            abi.encode(
                                                keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                                                keccak256(bytes(name)),
                                                keccak256("1"),
                                                block.chainid,
                                                address(this)
                                            )
                                        );
                                }
                                /*//////////////////////////////////////////////////////////////
                                                    INTERNAL MINT/BURN LOGIC
                                //////////////////////////////////////////////////////////////*/
                                function _mint(address to, uint256 amount) internal virtual {
                                    totalSupply += amount;
                                    // Cannot overflow because the sum of all user
                                    // balances can't exceed the max uint256 value.
                                    unchecked {
                                        balanceOf[to] += amount;
                                    }
                                    emit Transfer(address(0), to, amount);
                                }
                                function _burn(address from, uint256 amount) internal virtual {
                                    balanceOf[from] -= amount;
                                    // Cannot underflow because a user's balance
                                    // will never be larger than the total supply.
                                    unchecked {
                                        totalSupply -= amount;
                                    }
                                    emit Transfer(from, address(0), amount);
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity 0.8.17;
                            uint256 constant Bytes1_shift = 0xf8;
                            uint256 constant Bytes4_shift = 0xe0;
                            uint256 constant Bytes20_shift = 0x60;
                            uint256 constant One_word = 0x20;
                            uint256 constant Memory_pointer = 0x40;
                            uint256 constant AssetType_ERC721 = 0;
                            uint256 constant AssetType_ERC1155 = 1;
                            uint256 constant OrderType_ASK = 0;
                            uint256 constant OrderType_BID = 1;
                            uint256 constant Pool_withdrawFrom_selector = 0x9555a94200000000000000000000000000000000000000000000000000000000;
                            uint256 constant Pool_withdrawFrom_from_offset = 0x04;
                            uint256 constant Pool_withdrawFrom_to_offset = 0x24;
                            uint256 constant Pool_withdrawFrom_amount_offset = 0x44;
                            uint256 constant Pool_withdrawFrom_size = 0x64;
                            uint256 constant Pool_deposit_selector = 0xf340fa0100000000000000000000000000000000000000000000000000000000;
                            uint256 constant Pool_deposit_user_offset = 0x04;
                            uint256 constant Pool_deposit_size = 0x24;
                            uint256 constant ERC20_transferFrom_selector = 0x23b872dd00000000000000000000000000000000000000000000000000000000;
                            uint256 constant ERC721_safeTransferFrom_selector = 0x42842e0e00000000000000000000000000000000000000000000000000000000;
                            uint256 constant ERC1155_safeTransferFrom_selector = 0xf242432a00000000000000000000000000000000000000000000000000000000;
                            uint256 constant ERC20_transferFrom_size = 0x64;
                            uint256 constant ERC721_safeTransferFrom_size = 0x64;
                            uint256 constant ERC1155_safeTransferFrom_size = 0xc4;
                            uint256 constant OracleSignatures_size = 0x59;
                            uint256 constant OracleSignatures_s_offset = 0x20;
                            uint256 constant OracleSignatures_v_offset = 0x40;
                            uint256 constant OracleSignatures_blockNumber_offset = 0x41;
                            uint256 constant OracleSignatures_oracle_offset = 0x45;
                            uint256 constant Signatures_size = 0x41;
                            uint256 constant Signatures_s_offset = 0x20;
                            uint256 constant Signatures_v_offset = 0x40;
                            uint256 constant ERC20_transferFrom_from_offset = 0x4;
                            uint256 constant ERC20_transferFrom_to_offset = 0x24;
                            uint256 constant ERC20_transferFrom_amount_offset = 0x44;
                            uint256 constant ERC721_safeTransferFrom_from_offset = 0x4;
                            uint256 constant ERC721_safeTransferFrom_to_offset = 0x24;
                            uint256 constant ERC721_safeTransferFrom_id_offset = 0x44;
                            uint256 constant ERC1155_safeTransferFrom_from_offset = 0x4;
                            uint256 constant ERC1155_safeTransferFrom_to_offset = 0x24;
                            uint256 constant ERC1155_safeTransferFrom_id_offset = 0x44;
                            uint256 constant ERC1155_safeTransferFrom_amount_offset = 0x64;
                            uint256 constant ERC1155_safeTransferFrom_data_pointer_offset = 0x84;
                            uint256 constant ERC1155_safeTransferFrom_data_offset = 0xa4;
                            uint256 constant Delegate_transfer_selector = 0xa1ccb98e00000000000000000000000000000000000000000000000000000000;
                            uint256 constant Delegate_transfer_calldata_offset = 0x1c;
                            uint256 constant Order_size = 0x100;
                            uint256 constant Order_trader_offset = 0x00;
                            uint256 constant Order_collection_offset = 0x20;
                            uint256 constant Order_listingsRoot_offset = 0x40;
                            uint256 constant Order_numberOfListings_offset = 0x60;
                            uint256 constant Order_expirationTime_offset = 0x80;
                            uint256 constant Order_assetType_offset = 0xa0;
                            uint256 constant Order_makerFee_offset = 0xc0;
                            uint256 constant Order_salt_offset = 0xe0;
                            uint256 constant Exchange_size = 0x80;
                            uint256 constant Exchange_askIndex_offset = 0x00;
                            uint256 constant Exchange_proof_offset = 0x20;
                            uint256 constant Exchange_maker_offset = 0x40;
                            uint256 constant Exchange_taker_offset = 0x60;
                            uint256 constant BidExchange_size = 0x80;
                            uint256 constant BidExchange_askIndex_offset = 0x00;
                            uint256 constant BidExchange_proof_offset = 0x20;
                            uint256 constant BidExchange_maker_offset = 0x40;
                            uint256 constant BidExchange_taker_offset = 0x60;
                            uint256 constant Listing_size = 0x80;
                            uint256 constant Listing_index_offset = 0x00;
                            uint256 constant Listing_tokenId_offset = 0x20;
                            uint256 constant Listing_amount_offset = 0x40;
                            uint256 constant Listing_price_offset = 0x60;
                            uint256 constant Taker_size = 0x40;
                            uint256 constant Taker_tokenId_offset = 0x00;
                            uint256 constant Taker_amount_offset = 0x20;
                            uint256 constant StateUpdate_size = 0x80;
                            uint256 constant StateUpdate_salt_offset = 0x20;
                            uint256 constant StateUpdate_leaf_offset = 0x40;
                            uint256 constant StateUpdate_value_offset = 0x60;
                            uint256 constant Transfer_size = 0xa0;
                            uint256 constant Transfer_trader_offset = 0x00;
                            uint256 constant Transfer_id_offset = 0x20;
                            uint256 constant Transfer_amount_offset = 0x40;
                            uint256 constant Transfer_collection_offset = 0x60;
                            uint256 constant Transfer_assetType_offset = 0x80;
                            uint256 constant ExecutionBatch_selector_offset = 0x20;
                            uint256 constant ExecutionBatch_calldata_offset = 0x40;
                            uint256 constant ExecutionBatch_base_size = 0xa0; // size of the executionBatch without the flattened dynamic elements
                            uint256 constant ExecutionBatch_taker_offset = 0x00;
                            uint256 constant ExecutionBatch_orderType_offset = 0x20;
                            uint256 constant ExecutionBatch_transfers_pointer_offset = 0x40;
                            uint256 constant ExecutionBatch_length_offset = 0x60;
                            uint256 constant ExecutionBatch_transfers_offset = 0x80;
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.17;
                            struct TakeAsk {
                                Order[] orders;
                                Exchange[] exchanges;
                                FeeRate takerFee;
                                bytes signatures;
                                address tokenRecipient;
                            }
                            struct TakeAskSingle {
                                Order order;
                                Exchange exchange;
                                FeeRate takerFee;
                                bytes signature;
                                address tokenRecipient;
                            }
                            struct TakeBid {
                                Order[] orders;
                                Exchange[] exchanges;
                                FeeRate takerFee;
                                bytes signatures;
                            }
                            struct TakeBidSingle {
                                Order order;
                                Exchange exchange;
                                FeeRate takerFee;
                                bytes signature;
                            }
                            enum AssetType {
                                ERC721,
                                ERC1155
                            }
                            enum OrderType {
                                ASK,
                                BID
                            }
                            struct Exchange { // Size: 0x80
                                uint256 index; // 0x00
                                bytes32[] proof; // 0x20
                                Listing listing; // 0x40
                                Taker taker; // 0x60
                            }
                            struct Listing { // Size: 0x80
                                uint256 index; // 0x00
                                uint256 tokenId; // 0x20
                                uint256 amount; // 0x40
                                uint256 price; // 0x60
                            }
                            struct Taker { // Size: 0x40
                                uint256 tokenId; // 0x00
                                uint256 amount; // 0x20
                            }
                            struct Order { // Size: 0x100
                                address trader; // 0x00
                                address collection; // 0x20
                                bytes32 listingsRoot; // 0x40
                                uint256 numberOfListings; // 0x60
                                uint256 expirationTime; // 0x80
                                AssetType assetType; // 0xa0
                                FeeRate makerFee; // 0xc0
                                uint256 salt; // 0xe0
                            }
                            /*
                            Reference only; struct is composed manually using calldata formatting in execution
                            struct ExecutionBatch { // Size: 0x80
                                address taker; // 0x00
                                OrderType orderType; // 0x20
                                Transfer[] transfers; // 0x40
                                uint256 length; // 0x60
                            }
                            */
                            struct Transfer { // Size: 0xa0
                                address trader; // 0x00
                                uint256 id; // 0x20
                                uint256 amount; // 0x40
                                address collection; // 0x60
                                AssetType assetType; // 0x80
                            }
                            struct FungibleTransfers {
                                uint256 totalProtocolFee;
                                uint256 totalSellerTransfer;
                                uint256 totalTakerFee;
                                uint256 feeRecipientId;
                                uint256 makerId;
                                address[] feeRecipients;
                                address[] makers;
                                uint256[] makerTransfers;
                                uint256[] feeTransfers;
                                AtomicExecution[] executions;
                            }
                            struct AtomicExecution { // Size: 0xe0
                                uint256 makerId; // 0x00
                                uint256 sellerAmount; // 0x20
                                uint256 makerFeeRecipientId; // 0x40
                                uint256 makerFeeAmount; // 0x60
                                uint256 takerFeeAmount; // 0x80
                                uint256 protocolFeeAmount; // 0xa0
                                StateUpdate stateUpdate; // 0xc0
                            }
                            struct StateUpdate { // Size: 0xa0
                                address trader; // 0x00
                                bytes32 hash; // 0x20
                                uint256 index; // 0x40
                                uint256 value; // 0x60
                                uint256 maxAmount; // 0x80
                            }
                            struct Fees { // Size: 0x40
                                FeeRate protocolFee; // 0x00
                                FeeRate takerFee; // 0x20
                            }
                            struct FeeRate { // Size: 0x40
                                address recipient; // 0x00
                                uint16 rate; // 0x20
                            }
                            struct Cancel {
                                bytes32 hash;
                                uint256 index;
                                uint256 amount;
                            }