Quil QAT

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.1;

/// @author thirdweb, OpenZeppelin Contracts (v4.9.0)

/**
 * @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
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [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://consensys.net/diligence/blog/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/v0.8.0/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 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) {
        (bool success, bytes memory returndata) = target.delegatecall(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 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: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IContractMetadata.sol";

/**
 *  @title   Contract Metadata
 *  @notice  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *           for you contract.
 *           Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */

abstract contract ContractMetadata is IContractMetadata {
    /// @dev The sender is not authorized to perform the action
    error ContractMetadataUnauthorized();

    /// @notice Returns the contract metadata URI.
    string public override contractURI;

    /**
     *  @notice         Lets a contract admin set the URI for contract-level metadata.
     *  @dev            Caller should be authorized to setup contractURI, e.g. contract admin.
     *                  See {_canSetContractURI}.
     *                  Emits {ContractURIUpdated Event}.
     *
     *  @param _uri     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function setContractURI(string memory _uri) external override {
        if (!_canSetContractURI()) {
            revert ContractMetadataUnauthorized();
        }

        _setupContractURI(_uri);
    }

    /// @dev Lets a contract admin set the URI for contract-level metadata.
    function _setupContractURI(string memory _uri) internal {
        string memory prevURI = contractURI;
        contractURI = _uri;

        emit ContractURIUpdated(prevURI, _uri);
    }

    /// @dev Returns whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view virtual returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)

pragma solidity ^0.8.0;

/**
 * @title Counters
 * @author Matt Condon (@shrugs)
 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
 * of elements in a mapping, issuing ERC721 ids, or counting request ids.
 *
 * Include with `using Counters for Counters.Counter;`
 */
library Counters {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }

    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }

    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }

    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }

    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

// Helper interfaces
import { IWETH } from "../infra/interface/IWETH.sol";
import { SafeERC20, IERC20 } from "../external-deps/openzeppelin/token/ERC20/utils/SafeERC20.sol";

library CurrencyTransferLib {
    using SafeERC20 for IERC20;

    error CurrencyTransferLibMismatchedValue(uint256 expected, uint256 actual);
    error CurrencyTransferLibFailedNativeTransfer(address recipient, uint256 value);

    /// @dev The address interpreted as native token of the chain.
    address public constant NATIVE_TOKEN = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;

    /// @dev Transfers a given amount of currency.
    function transferCurrency(address _currency, address _from, address _to, uint256 _amount) internal {
        if (_amount == 0) {
            return;
        }

        if (_currency == NATIVE_TOKEN) {
            safeTransferNativeToken(_to, _amount);
        } else {
            safeTransferERC20(_currency, _from, _to, _amount);
        }
    }

    /// @dev Transfers a given amount of currency. (With native token wrapping)
    function transferCurrencyWithWrapper(
        address _currency,
        address _from,
        address _to,
        uint256 _amount,
        address _nativeTokenWrapper
    ) internal {
        if (_amount == 0) {
            return;
        }

        if (_currency == NATIVE_TOKEN) {
            if (_from == address(this)) {
                // withdraw from weth then transfer withdrawn native token to recipient
                IWETH(_nativeTokenWrapper).withdraw(_amount);
                safeTransferNativeTokenWithWrapper(_to, _amount, _nativeTokenWrapper);
            } else if (_to == address(this)) {
                // store native currency in weth
                if (_amount != msg.value) {
                    revert CurrencyTransferLibMismatchedValue(msg.value, _amount);
                }
                IWETH(_nativeTokenWrapper).deposit{ value: _amount }();
            } else {
                safeTransferNativeTokenWithWrapper(_to, _amount, _nativeTokenWrapper);
            }
        } else {
            safeTransferERC20(_currency, _from, _to, _amount);
        }
    }

    /// @dev Transfer `amount` of ERC20 token from `from` to `to`.
    function safeTransferERC20(address _currency, address _from, address _to, uint256 _amount) internal {
        if (_from == _to) {
            return;
        }

        if (_from == address(this)) {
            IERC20(_currency).safeTransfer(_to, _amount);
        } else {
            IERC20(_currency).safeTransferFrom(_from, _to, _amount);
        }
    }

    /// @dev Transfers `amount` of native token to `to`.
    function safeTransferNativeToken(address to, uint256 value) internal {
        // solhint-disable avoid-low-level-calls
        // slither-disable-next-line low-level-calls
        (bool success, ) = to.call{ value: value }("");
        if (!success) {
            revert CurrencyTransferLibFailedNativeTransfer(to, value);
        }
    }

    /// @dev Transfers `amount` of native token to `to`. (With native token wrapping)
    function safeTransferNativeTokenWithWrapper(address to, uint256 value, address _nativeTokenWrapper) internal {
        // solhint-disable avoid-low-level-calls
        // slither-disable-next-line low-level-calls
        (bool success, ) = to.call{ value: value }("");
        if (!success) {
            IWETH(_nativeTokenWrapper).deposit{ value: value }();
            IERC20(_nativeTokenWrapper).safeTransfer(to, value);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;

import "../../../../lib/Strings.sol";

/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
    enum RecoverError {
        NoError,
        InvalidSignature,
        InvalidSignatureLength,
        InvalidSignatureS,
        InvalidSignatureV // Deprecated in v4.8
    }

    function _throwError(RecoverError error) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert("ECDSA: invalid signature");
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert("ECDSA: invalid signature length");
        } else if (error == RecoverError.InvalidSignatureS) {
            revert("ECDSA: invalid signature 's' value");
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature` or error string. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     *
     * Documentation for signature generation:
     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            /// @solidity memory-safe-assembly
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, signature);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
     *
     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address, RecoverError) {
        bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
        uint8 v = uint8((uint256(vs) >> 255) + 27);
        return tryRecover(hash, v, r, s);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
     *
     * _Available since v4.2._
     */
    function recover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, r, vs);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
     * `r` and `s` signature fields separately.
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address, RecoverError) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return (address(0), RecoverError.InvalidSignatureS);
        }

        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            return (address(0), RecoverError.InvalidSignature);
        }

        return (signer, RecoverError.NoError);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 message) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, "\x19Ethereum Signed Message:\n32")
            mstore(0x1c, hash)
            message := keccak256(0x00, 0x3c)
        }
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from `s`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
    }

    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 data) {
        /// @solidity memory-safe-assembly
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, "\x19\x01")
            mstore(add(ptr, 0x02), domainSeparator)
            mstore(add(ptr, 0x22), structHash)
            data := keccak256(ptr, 0x42)
        }
    }

    /**
     * @dev Returns an Ethereum Signed Data with intended validator, created from a
     * `validator` and `data` according to the version 0 of EIP-191.
     *
     * See {recover}.
     */
    function toDataWithIntendedValidatorHash(address validator, bytes memory data) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x00", validator, data));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol)

pragma solidity ^0.8.0;

import "./ECDSA.sol";

/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
    uint256 private immutable _CACHED_CHAIN_ID;
    address private immutable _CACHED_THIS;

    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;

    /* solhint-enable var-name-mixedcase */

    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        bytes32 hashedName = keccak256(bytes(name));
        bytes32 hashedVersion = keccak256(bytes(version));
        bytes32 typeHash = keccak256(
            "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
        );
        _HASHED_NAME = hashedName;
        _HASHED_VERSION = hashedVersion;
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
        _CACHED_THIS = address(this);
        _TYPE_HASH = typeHash;
    }

    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
        }
    }

    function _buildDomainSeparator(
        bytes32 typeHash,
        bytes32 nameHash,
        bytes32 versionHash
    ) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
    }

    /**
     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
     * function returns the hash of the fully encoded EIP712 message for this domain.
     *
     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
     *
     * ```solidity
     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
     *     keccak256("Mail(address to,string contents)"),
     *     mailTo,
     *     keccak256(bytes(mailContents))
     * )));
     * address signer = ECDSA.recover(digest, signature);
     * ```
     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "../../../../eip/interface/IERC20.sol";
import "../../../../eip/interface/IERC20Metadata.sol";
import "../../utils/Context.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, _allowances[owner][spender] + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = _allowances[owner][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `sender` to `recipient`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(address from, address to, uint256 amount) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Spend `amount` form the allowance of `owner` toward `spender`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens 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 amount) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been 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 _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "../external-deps/openzeppelin/token/ERC20/extensions/ERC20Permit.sol";

import "../extension/ContractMetadata.sol";
import "../extension/Multicall.sol";
import "../extension/Ownable.sol";
import "../extension/interface/IMintableERC20.sol";
import "../extension/interface/IBurnableERC20.sol";

/**
 *  The `ERC20Base` smart contract implements the ERC20 standard.
 *  It includes the following additions to standard ERC20 logic:
 *
 *      - Ability to mint & burn tokens via the provided `mint` & `burn` functions.
 *
 *      - Ownership of the contract, with the ability to restrict certain functions to
 *        only be called by the contract's owner.
 *
 *      - Multicall capability to perform multiple actions atomically
 *
 *      - EIP 2612 compliance: See {ERC20-permit} method, which can be used to change an account's ERC20 allowance by
 *                             presenting a message signed by the account.
 */

contract ERC20Base is ContractMetadata, Multicall, Ownable, ERC20Permit, IMintableERC20, IBurnableERC20 {
    /*//////////////////////////////////////////////////////////////
                            Constructor
    //////////////////////////////////////////////////////////////*/

    constructor(address _defaultAdmin, string memory _name, string memory _symbol) ERC20Permit(_name, _symbol) {
        _setupOwner(_defaultAdmin);
    }

    /*//////////////////////////////////////////////////////////////
                            Minting logic
    //////////////////////////////////////////////////////////////*/

    /**
     *  @notice          Lets an authorized address mint tokens to a recipient.
     *  @dev             The logic in the `_canMint` function determines whether the caller is authorized to mint tokens.
     *
     *  @param _to       The recipient of the tokens to mint.
     *  @param _amount   Quantity of tokens to mint.
     */
    function mintTo(address _to, uint256 _amount) public virtual {
        require(_canMint(), "Not authorized to mint.");
        require(_amount != 0, "Minting zero tokens.");

        _mint(_to, _amount);
    }

    /**
     *  @notice          Lets an owner a given amount of their tokens.
     *  @dev             Caller should own the `_amount` of tokens.
     *
     *  @param _amount   The number of tokens to burn.
     */
    function burn(uint256 _amount) external virtual {
        require(balanceOf(msg.sender) >= _amount, "not enough balance");
        _burn(msg.sender, _amount);
    }

    /**
     *  @notice          Lets an owner burn a given amount of an account's tokens.
     *  @dev             `_account` should own the `_amount` of tokens.
     *
     *  @param _account  The account to burn tokens from.
     *  @param _amount   The number of tokens to burn.
     */
    function burnFrom(address _account, uint256 _amount) external virtual override {
        require(_canBurn(), "Not authorized to burn.");
        require(balanceOf(_account) >= _amount, "not enough balance");
        uint256 decreasedAllowance = allowance(_account, msg.sender) - _amount;
        _approve(_account, msg.sender, 0);
        _approve(_account, msg.sender, decreasedAllowance);
        _burn(_account, _amount);
    }

    /*//////////////////////////////////////////////////////////////
                        Internal (overrideable) functions
    //////////////////////////////////////////////////////////////*/

    /// @dev Returns whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view virtual override returns (bool) {
        return msg.sender == owner();
    }

    /// @dev Returns whether tokens can be minted in the given execution context.
    function _canMint() internal view virtual returns (bool) {
        return msg.sender == owner();
    }

    /// @dev Returns whether tokens can be burned in the given execution context.
    function _canBurn() internal view virtual returns (bool) {
        return msg.sender == owner();
    }

    /// @dev Returns whether owner can be set in the given execution context.
    function _canSetOwner() internal view virtual override returns (bool) {
        return msg.sender == owner();
    }

    /// @notice Returns the sender in the given execution context.
    function _msgSender() internal view override(Multicall, Context) returns (address) {
        return msg.sender;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-ERC20Permit.sol)

pragma solidity ^0.8.0;

import "../../../../../eip/interface/IERC20Permit.sol";
import "../ERC20.sol";
import "../../../utils/cryptography/EIP712.sol";
import "../../../utils/cryptography/ECDSA.sol";
import "../../../utils/Counters.sol";

/**
 * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * _Available since v3.4._
 */
abstract contract ERC20Permit is ERC20, IERC20Permit {
    using Counters for Counters.Counter;

    mapping(address => Counters.Counter) private _nonces;

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;

    // solhint-disable-next-line var-name-mixedcase
    uint256 private immutable _CACHED_CHAIN_ID;

    // solhint-disable-next-line var-name-mixedcase
    address private immutable _CACHED_THIS;

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private immutable _PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");

    /**
     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
     *
     * It's a good idea to use the same `name` that is defined as the ERC20 token name.
     */
    constructor(string memory name_, string memory symbol_) ERC20(name_, symbol_) {
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_THIS = address(this);
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator();
    }

    /**
     * @dev See {IERC20Permit-permit}.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual override {
        require(block.timestamp <= deadline, "ERC20Permit: expired deadline");

        bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));

        bytes32 hash = ECDSA.toTypedDataHash(DOMAIN_SEPARATOR(), structHash);

        address signer = ECDSA.recover(hash, v, r, s);
        require(signer == owner, "ERC20Permit: invalid signature");

        _approve(owner, spender, value);
    }

    /**
     * @dev See {IERC20Permit-nonces}.
     */
    function nonces(address owner) public view virtual override returns (uint256) {
        return _nonces[owner].current();
    }

    /**
     * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() public view override returns (bytes32) {
        if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator();
        }
    }

    function _buildDomainSeparator() private view 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)
                )
            );
    }

    /**
     * @dev "Consume a nonce": return the current value and increment.
     *
     * _Available since v4.1._
     */
    function _useNonce(address owner) internal virtual returns (uint256 current) {
        Counters.Counter storage nonce = _nonces[owner];
        current = nonce.current();
        nonce.increment();
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./ERC20Base.sol";

import "../extension/PrimarySale.sol";
import { SignatureMintERC20 } from "../extension/SignatureMintERC20.sol";
import { ReentrancyGuard } from "../extension/upgradeable/ReentrancyGuard.sol";
import { CurrencyTransferLib } from "../lib/CurrencyTransferLib.sol";

/**
 *      BASE:      ERC20
 *      EXTENSION: SignatureMintERC20
 *
 *  The `ERC20SignatureMint` contract uses the `ERC20Base` contract, along with the `SignatureMintERC20` extension.
 *
 *  The 'signature minting' mechanism in the `SignatureMintERC20` extension uses EIP 712, and is a way for a contract
 *  admin to authorize an external party's request to mint tokens on the admin's contract. At a high level, this means
 *  you can authorize some external party to mint tokens on your contract, and specify what exactly will be minted by
 *  that external party.
 *
 */

contract ERC20SignatureMint is ERC20Base, PrimarySale, SignatureMintERC20, ReentrancyGuard {
    /*//////////////////////////////////////////////////////////////
                            Constructor
    //////////////////////////////////////////////////////////////*/

    constructor(
        address _defaultAdmin,
        string memory _name,
        string memory _symbol,
        address _primarySaleRecipient
    ) ERC20Base(_defaultAdmin, _name, _symbol) {
        _setupPrimarySaleRecipient(_primarySaleRecipient);
    }

    /*//////////////////////////////////////////////////////////////
                        Signature minting logic
    //////////////////////////////////////////////////////////////*/

    /**
     *  @notice           Mints tokens according to the provided mint request.
     *
     *  @param _req       The payload / mint request.
     *  @param _signature The signature produced by an account signing the mint request.
     */
    function mintWithSignature(
        MintRequest calldata _req,
        bytes calldata _signature
    ) external payable virtual nonReentrant returns (address signer) {
        require(_req.quantity > 0, "Minting zero tokens.");

        // Verify and process payload.
        signer = _processRequest(_req, _signature);

        address receiver = _req.to;

        // Collect price
        _collectPriceOnClaim(_req.primarySaleRecipient, _req.currency, _req.price);

        // Mint tokens.
        _mint(receiver, _req.quantity);

        emit TokensMintedWithSignature(signer, receiver, _req);
    }

    /*//////////////////////////////////////////////////////////////
                            Internal functions
    //////////////////////////////////////////////////////////////*/

    /// @dev Returns whether a given address is authorized to sign mint requests.
    function _canSignMintRequest(address _signer) internal view virtual override returns (bool) {
        return _signer == owner();
    }

    /// @dev Returns whether primary sale recipient can be set in the given execution context.
    function _canSetPrimarySaleRecipient() internal view virtual override returns (bool) {
        return msg.sender == owner();
    }

    /// @dev Collects and distributes the primary sale value of tokens being claimed.
    function _collectPriceOnClaim(address _primarySaleRecipient, address _currency, uint256 _price) internal virtual {
        if (_price == 0) {
            require(msg.value == 0, "!Value");
            return;
        }

        if (_currency == CurrencyTransferLib.NATIVE_TOKEN) {
            require(msg.value == _price, "Must send total price.");
        } else {
            require(msg.value == 0, "msg value not zero");
        }

        address saleRecipient = _primarySaleRecipient == address(0) ? primarySaleRecipient() : _primarySaleRecipient;
        CurrencyTransferLib.transferCurrency(_currency, msg.sender, saleRecipient, _price);
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

interface IBurnableERC20 {
    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) external;

    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for ``accounts``'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) external;
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 *  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *  for you contract.
 *
 *  Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */

interface IContractMetadata {
    /// @dev Returns the metadata URI of the contract.
    function contractURI() external view returns (string memory);

    /**
     *  @dev Sets contract URI for the storefront-level metadata of the contract.
     *       Only module admin can call this function.
     */
    function setContractURI(string calldata _uri) external;

    /// @dev Emitted when the contract URI is updated.
    event ContractURIUpdated(string prevURI, string newURI);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20 {
    function totalSupply() external view returns (uint256);

    function balanceOf(address who) external view returns (uint256);

    function allowance(address owner, address spender) external view returns (uint256);

    function transfer(address to, uint256 value) external returns (bool);

    function approve(address spender, uint256 value) external returns (bool);

    function transferFrom(address from, address to, uint256 value) external returns (bool);

    event Transfer(address indexed from, address indexed to, uint256 value);

    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/**
 * @title ERC20Metadata interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20Metadata {
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

interface IMintableERC20 {
    /// @dev Emitted when tokens are minted with `mintTo`
    event TokensMinted(address indexed mintedTo, uint256 quantityMinted);

    /**
     * @dev Creates `amount` new tokens for `to`.
     *
     * See {ERC20-_mint}.
     *
     * Requirements:
     *
     * - the caller must have the `MINTER_ROLE`.
     */
    function mintTo(address to, uint256 amount) external;
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 * @dev Provides a function to batch together multiple calls in a single external call.
 *
 * _Available since v4.1._
 */
interface IMulticall {
    /**
     * @dev Receives and executes a batch of function calls on this contract.
     */
    function multicall(bytes[] calldata data) external returns (bytes[] memory results);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 *  Thirdweb's `Ownable` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *  who the 'owner' of the inheriting smart contract is, and lets the inheriting contract perform conditional logic that uses
 *  information about who the contract's owner is.
 */

interface IOwnable {
    /// @dev Returns the owner of the contract.
    function owner() external view returns (address);

    /// @dev Lets a module admin set a new owner for the contract. The new owner must be a module admin.
    function setOwner(address _newOwner) external;

    /// @dev Emitted when a new Owner is set.
    event OwnerUpdated(address indexed prevOwner, address indexed newOwner);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 *  Thirdweb's `Primary` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *  the recipient of primary sales, and lets the inheriting contract perform conditional logic that uses information about
 *  primary sales, if desired.
 */

interface IPrimarySale {
    /// @dev The adress that receives all primary sales value.
    function primarySaleRecipient() external view returns (address);

    /// @dev Lets a module admin set the default recipient of all primary sales.
    function setPrimarySaleRecipient(address _saleRecipient) external;

    /// @dev Emitted when a new sale recipient is set.
    event PrimarySaleRecipientUpdated(address indexed recipient);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 *  The 'signature minting' mechanism used in thirdweb Token smart contracts is a way for a contract admin to authorize an external party's
 *  request to mint tokens on the admin's contract.
 *
 *  At a high level, this means you can authorize some external party to mint tokens on your contract, and specify what exactly will be
 *  minted by that external party.
 */
interface ISignatureMintERC20 {
    /**
     *  @notice The body of a request to mint tokens.
     *
     *  @param to The receiver of the tokens to mint.
     *  @param primarySaleRecipient The recipient of the minted token's primary sales proceeds.
     *  @param quantity The quantity of tokens to mint.
     *  @param pricePerToken The price to pay per quantity of tokens minted.
     *  @param currency The currency in which to pay the price per token minted.
     *  @param validityStartTimestamp The unix timestamp after which the payload is valid.
     *  @param validityEndTimestamp The unix timestamp at which the payload expires.
     *  @param uid A unique identifier for the payload.
     */
    struct MintRequest {
        address to;
        address primarySaleRecipient;
        uint256 quantity;
        uint256 price;
        address currency;
        uint128 validityStartTimestamp;
        uint128 validityEndTimestamp;
        bytes32 uid;
    }

    /// @dev Emitted when tokens are minted.
    event TokensMintedWithSignature(address indexed signer, address indexed mintedTo, MintRequest mintRequest);

    /**
     *  @notice Verifies that a mint request is signed by an account holding
     *          MINTER_ROLE (at the time of the function call).
     *
     *  @param req The payload / mint request.
     *  @param signature The signature produced by an account signing the mint request.
     *
     *  returns (success, signer) Result of verification and the recovered address.
     */
    function verify(
        MintRequest calldata req,
        bytes calldata signature
    ) external view returns (bool success, address signer);

    /**
     *  @notice Mints tokens according to the provided mint request.
     *
     *  @param req The payload / mint request.
     *  @param signature The signature produced by an account signing the mint request.
     */
    function mintWithSignature(
        MintRequest calldata req,
        bytes calldata signature
    ) external payable returns (address signer);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

interface IWETH {
    function deposit() external payable;

    function withdraw(uint256 amount) external;

    function transfer(address to, uint256 value) external returns (bool);
}

// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "../lib/Address.sol";
import "./interface/IMulticall.sol";

/**
 * @dev Provides a function to batch together multiple calls in a single external call.
 *
 * _Available since v4.1._
 */
contract Multicall is IMulticall {
    /**
     *  @notice Receives and executes a batch of function calls on this contract.
     *  @dev Receives and executes a batch of function calls on this contract.
     *
     *  @param data The bytes data that makes up the batch of function calls to execute.
     *  @return results The bytes data that makes up the result of the batch of function calls executed.
     */
    function multicall(bytes[] calldata data) external returns (bytes[] memory results) {
        results = new bytes[](data.length);
        address sender = _msgSender();
        bool isForwarder = msg.sender != sender;
        for (uint256 i = 0; i < data.length; i++) {
            if (isForwarder) {
                results[i] = Address.functionDelegateCall(address(this), abi.encodePacked(data[i], sender));
            } else {
                results[i] = Address.functionDelegateCall(address(this), data[i]);
            }
        }
        return results;
    }

    /// @notice Returns the sender in the given execution context.
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IOwnable.sol";

/**
 *  @title   Ownable
 *  @notice  Thirdweb's `Ownable` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *           who the 'owner' of the inheriting smart contract is, and lets the inheriting contract perform conditional logic that uses
 *           information about who the contract's owner is.
 */

abstract contract Ownable is IOwnable {
    /// @dev The sender is not authorized to perform the action
    error OwnableUnauthorized();

    /// @dev Owner of the contract (purpose: OpenSea compatibility)
    address private _owner;

    /// @dev Reverts if caller is not the owner.
    modifier onlyOwner() {
        if (msg.sender != _owner) {
            revert OwnableUnauthorized();
        }
        _;
    }

    /**
     *  @notice Returns the owner of the contract.
     */
    function owner() public view override returns (address) {
        return _owner;
    }

    /**
     *  @notice Lets an authorized wallet set a new owner for the contract.
     *  @param _newOwner The address to set as the new owner of the contract.
     */
    function setOwner(address _newOwner) external override {
        if (!_canSetOwner()) {
            revert OwnableUnauthorized();
        }
        _setupOwner(_newOwner);
    }

    /// @dev Lets a contract admin set a new owner for the contract. The new owner must be a contract admin.
    function _setupOwner(address _newOwner) internal {
        address _prevOwner = _owner;
        _owner = _newOwner;

        emit OwnerUpdated(_prevOwner, _newOwner);
    }

    /// @dev Returns whether owner can be set in the given execution context.
    function _canSetOwner() internal view virtual returns (bool);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IPrimarySale.sol";

/**
 *  @title   Primary Sale
 *  @notice  Thirdweb's `PrimarySale` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *           the recipient of primary sales, and lets the inheriting contract perform conditional logic that uses information about
 *           primary sales, if desired.
 */

abstract contract PrimarySale is IPrimarySale {
    /// @dev The sender is not authorized to perform the action
    error PrimarySaleUnauthorized();

    /// @dev The recipient is invalid
    error PrimarySaleInvalidRecipient(address recipient);

    /// @dev The address that receives all primary sales value.
    address private recipient;

    /// @dev Returns primary sale recipient address.
    function primarySaleRecipient() public view override returns (address) {
        return recipient;
    }

    /**
     *  @notice         Updates primary sale recipient.
     *  @dev            Caller should be authorized to set primary sales info.
     *                  See {_canSetPrimarySaleRecipient}.
     *                  Emits {PrimarySaleRecipientUpdated Event}; See {_setupPrimarySaleRecipient}.
     *
     *  @param _saleRecipient   Address to be set as new recipient of primary sales.
     */
    function setPrimarySaleRecipient(address _saleRecipient) external override {
        if (!_canSetPrimarySaleRecipient()) {
            revert PrimarySaleUnauthorized();
        }
        _setupPrimarySaleRecipient(_saleRecipient);
    }

    /// @dev Lets a contract admin set the recipient for all primary sales.
    function _setupPrimarySaleRecipient(address _saleRecipient) internal {
        if (_saleRecipient == address(0)) {
            revert PrimarySaleInvalidRecipient(_saleRecipient);
        }

        recipient = _saleRecipient;
        emit PrimarySaleRecipientUpdated(_saleRecipient);
    }

    /// @dev Returns whether primary sale recipient can be set in the given execution context.
    function _canSetPrimarySaleRecipient() internal view virtual returns (bool);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@thirdweb-dev/contracts/base/ERC20SignatureMint.sol";

contract QAT is ERC20SignatureMint {
      constructor(
        address _defaultAdmin,
        string memory _name,
        string memory _symbol,
        address _primarySaleRecipient
    )
        ERC20SignatureMint(
            _defaultAdmin,
            _name,
            _symbol,
            _primarySaleRecipient
        )
    {}

    function decimals() public view override returns (uint8) {
        return 8;
    }

}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

library ReentrancyGuardStorage {
    /// @custom:storage-location erc7201:reentrancy.guard.storage
    /// @dev keccak256(abi.encode(uint256(keccak256("reentrancy.guard.storage")) - 1)) & ~bytes32(uint256(0xff))
    bytes32 public constant REENTRANCY_GUARD_STORAGE_POSITION =
        0x1d281c488dae143b6ea4122e80c65059929950b9c32f17fc57be22089d9c3b00;

    struct Data {
        uint256 _status;
    }

    function data() internal pure returns (Data storage data_) {
        bytes32 position = REENTRANCY_GUARD_STORAGE_POSITION;
        assembly {
            data_.slot := position
        }
    }
}

abstract contract ReentrancyGuard {
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    constructor() {
        _reentrancyGuardStorage()._status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_reentrancyGuardStorage()._status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _reentrancyGuardStorage()._status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _reentrancyGuardStorage()._status = _NOT_ENTERED;
    }

    /// @dev Returns the ReentrancyGuard storage.
    function _reentrancyGuardStorage() internal pure returns (ReentrancyGuardStorage.Data storage data) {
        data = ReentrancyGuardStorage.data();
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../../../../../eip/interface/IERC20.sol";
import { Address } from "../../../../../lib/Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/ISignatureMintERC20.sol";
import "../external-deps/openzeppelin/utils/cryptography/EIP712.sol";

abstract contract SignatureMintERC20 is EIP712, ISignatureMintERC20 {
    using ECDSA for bytes32;

    bytes32 private constant TYPEHASH =
        keccak256(
            "MintRequest(address to,address primarySaleRecipient,uint256 quantity,uint256 price,address currency,uint128 validityStartTimestamp,uint128 validityEndTimestamp,bytes32 uid)"
        );

    /// @dev Mapping from mint request UID => whether the mint request is processed.
    mapping(bytes32 => bool) private minted;

    constructor() EIP712("SignatureMintERC20", "1") {}

    /// @dev Verifies that a mint request is signed by an account holding MINTER_ROLE (at the time of the function call).
    function verify(
        MintRequest calldata _req,
        bytes calldata _signature
    ) public view override returns (bool success, address signer) {
        signer = _recoverAddress(_req, _signature);
        success = !minted[_req.uid] && _canSignMintRequest(signer);
    }

    /// @dev Returns whether a given address is authorized to sign mint requests.
    function _canSignMintRequest(address _signer) internal view virtual returns (bool);

    /// @dev Verifies a mint request and marks the request as minted.
    function _processRequest(MintRequest calldata _req, bytes calldata _signature) internal returns (address signer) {
        bool success;
        (success, signer) = verify(_req, _signature);

        require(success, "Invalid request");
        require(
            _req.validityStartTimestamp <= block.timestamp && block.timestamp <= _req.validityEndTimestamp,
            "Request expired"
        );
        require(_req.to != address(0), "recipient undefined");
        require(_req.quantity > 0, "0 qty");

        minted[_req.uid] = true;
    }

    /// @dev Returns the address of the signer of the mint request.
    function _recoverAddress(MintRequest calldata _req, bytes calldata _signature) internal view returns (address) {
        return _hashTypedDataV4(keccak256(_encodeRequest(_req))).recover(_signature);
    }

    /// @dev Resolves 'stack too deep' error in `recoverAddress`.
    function _encodeRequest(MintRequest calldata _req) internal pure returns (bytes memory) {
        return
            abi.encode(
                TYPEHASH,
                _req.to,
                _req.primarySaleRecipient,
                _req.quantity,
                _req.price,
                _req.currency,
                _req.validityStartTimestamp,
                _req.validityEndTimestamp,
                _req.uid
            );
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 * @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);
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x", encoded using 2 hexadecimal digits per byte,
    /// and the alphabets are capitalized conditionally according to
    /// https://eips.ethereum.org/EIPS/eip-55
    function toHexStringChecksummed(address value) internal pure returns (string memory str) {
        str = toHexString(value);
        /// @solidity memory-safe-assembly
        assembly {
            let mask := shl(6, div(not(0), 255)) // `0b010000000100000000 ...`
            let o := add(str, 0x22)
            let hashed := and(keccak256(o, 40), mul(34, mask)) // `0b10001000 ... `
            let t := shl(240, 136) // `0b10001000 << 240`
            for {
                let i := 0
            } 1 {

            } {
                mstore(add(i, i), mul(t, byte(i, hashed)))
                i := add(i, 1)
                if eq(i, 20) {
                    break
                }
            }
            mstore(o, xor(mload(o), shr(1, and(mload(0x00), and(mload(o), mask)))))
            o := add(o, 0x20)
            mstore(o, xor(mload(o), shr(1, and(mload(0x20), and(mload(o), mask)))))
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x" and encoded using 2 hexadecimal digits per byte.
    function toHexString(address value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(address value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            str := mload(0x40)

            // Allocate the memory.
            // We need 0x20 bytes for the trailing zeros padding, 0x20 bytes for the length,
            // 0x02 bytes for the prefix, and 0x28 bytes for the digits.
            // The next multiple of 0x20 above (0x20 + 0x20 + 0x02 + 0x28) is 0x80.
            mstore(0x40, add(str, 0x80))

            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            str := add(str, 2)
            mstore(str, 40)

            let o := add(str, 0x20)
            mstore(add(o, 40), 0)

            value := shl(96, value)

            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for {
                let i := 0
            } 1 {

            } {
                let p := add(o, add(i, i))
                let temp := byte(i, value)
                mstore8(add(p, 1), mload(and(temp, 15)))
                mstore8(p, mload(shr(4, temp)))
                i := add(i, 1)
                if eq(i, 20) {
                    break
                }
            }
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexString(bytes memory raw) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(raw);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(bytes memory raw) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            let length := mload(raw)
            str := add(mload(0x40), 2) // Skip 2 bytes for the optional prefix.
            mstore(str, add(length, length)) // Store the length of the output.

            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let o := add(str, 0x20)
            let end := add(raw, length)

            for {

            } iszero(eq(raw, end)) {

            } {
                raw := add(raw, 1)
                mstore8(add(o, 1), mload(and(mload(raw), 15)))
                mstore8(o, mload(and(shr(4, mload(raw)), 15)))
                o := add(o, 2)
            }
            mstore(o, 0) // Zeroize the slot after the string.
            mstore(0x40, add(o, 0x20)) // Allocate the memory.
        }
    }
}

{
  "compilationTarget": {
    "QAT/QAT Contracts/contracts/QAT.sol": "QAT"
  },
  "evmVersion": "cancun",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}