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Contract Diff Checker

Contract Name:
FacetEthscriptionBridgeV4

Contract Source Code:

// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;

import "solady/src/utils/ECDSA.sol";
import "solady/src/utils/EIP712.sol";
import "solady/src/utils/LibString.sol";
import "solady/src/utils/ERC1967FactoryConstants.sol";

interface ControlledBridge {
    function controllerTransferEthscriptions(address recipient, bytes32[] calldata ethscriptionId) external;
}

contract FacetEthscriptionBridgeV4 is EIP712 {
    using LibString for *;
    using ECDSA for bytes32;
    
    event ethscriptions_protocol_TransferEthscription(
        address indexed recipient,
        bytes32 indexed id
    );

    event ethscriptions_protocol_CreateEthscription(
        address indexed initialOwner,
        string contentURI
    );
    
    struct WithdrawRequest {
        address recipient;
        bytes32[] ethscriptionIds;
        bytes32[] depositIds;
        bytes32 withdrawalId;
        bytes32 blockHash;
        uint256 blockNumber;
        bytes signature;
    }
    
    struct DepositConfirmation {
        address sender;
        bytes ethscriptionIds;
        bytes32 depositId;
        bytes32 blockHash;
        uint256 blockNumber;
        bytes signature;
    }

    struct BridgeStorage {
        mapping(bytes32 => bool) processedWithdrawalIds;
        bool depositEnabled;
        bool withdrawEnabled;
        address adminAddress;
        address signerAddress;
        address dumbContractAddress;
        uint256 cancelBlockNumber;
        mapping(address => bytes32[]) pendingDeposits;
        mapping(bytes32 => bool) processedDepositIds;
        uint256 withdrawDelay;
        ControlledBridge controlledBridge;

        mapping(address => bytes32) pendingDepositHash;
        mapping(bytes32 => mapping(bytes32 => bool)) processedWithdrawalsPerDeposit;
        uint16 bridgeInLimit;
    }
    
    function s() internal pure returns (BridgeStorage storage cs) {
        bytes32 position = keccak256("BridgeStorage.contract.storage.v1");
        assembly {
           cs.slot := position
        }
    }
    
    modifier onlyAdmin() {
        require(msg.sender == s().adminAddress, "Not admin");
        _;
    }
    
    function initialize(
        address adminAddress
    ) external {
        require(msg.sender == ERC1967FactoryConstants.ADDRESS, "Not factory");
        require(s().adminAddress == address(0), "Already initialized");
        require(adminAddress != address(0), "No zero address");

        s().adminAddress = adminAddress;
    }
    
    function withdraw(
        WithdrawRequest calldata req
    ) external {
        require(s().withdrawEnabled, "Withdraw not enabled");

        bytes32 hashedMessage = _hashTypedData(keccak256(abi.encode(
            keccak256(
                "Withdraw(address recipient,address dumbContract,bytes32 ethscriptionIds,"
                "bytes32 depositIds,bytes32 withdrawalId,bytes32 blockHash,uint256 blockNumber)"
            ),
            req.recipient,
            s().dumbContractAddress,
            keccak256(abi.encodePacked(req.ethscriptionIds)),
            keccak256(abi.encodePacked(req.depositIds)),
            req.withdrawalId,
            req.blockHash,
            req.blockNumber
        )));

        address signer = hashedMessage.recoverCalldata(req.signature);

        require(signer == s().signerAddress, "Invalid signature");
        require(!s().processedWithdrawalIds[req.withdrawalId], "Already processed");
        require(s().cancelBlockNumber <= req.blockNumber, "Signature canceled");
        require(block.number >= req.blockNumber + s().withdrawDelay, "Withdraw delay");
        require(req.blockHash == bytes32(0) || blockhash(req.blockNumber) == req.blockHash, "Invalid block number or hash");
        require(req.ethscriptionIds.length > 0, "No ethscriptions");
        require(req.ethscriptionIds.length == req.depositIds.length, "Length mismatch");
        
        s().processedWithdrawalIds[req.withdrawalId] = true;
        
        for (uint256 i; i < req.ethscriptionIds.length;) {
            bytes32 ethscriptionId = req.ethscriptionIds[i];
            bytes32 depositId = req.depositIds[i];
            
            require(!s().processedWithdrawalsPerDeposit[ethscriptionId][depositId], "Already processed");
            s().processedWithdrawalsPerDeposit[ethscriptionId][depositId] = true;
            
            emit ethscriptions_protocol_TransferEthscription(
                req.recipient,
                ethscriptionId
            );
            
            unchecked { ++i; }
        }
        
        string memory out = string.concat(
            'data:application/vnd.facet.tx+json;rule=esip6,{"op":"call","data":{"to":"',
            s().dumbContractAddress.toHexString(),
            '","function":"markWithdrawalComplete","args":{"to":"',
            req.recipient.toHexString(),
            '","withdrawalId":"',
            uint256(req.withdrawalId).toHexString(32),
            '"}}}'
        );
        
        emit ethscriptions_protocol_CreateEthscription(0x00000000000000000000000000000000000FacE7, string(out));
    }

    function confirmDeposit(
        DepositConfirmation calldata deposit
    ) external {
        require(s().depositEnabled, "Deposit not enabled");

        bytes32 hashedMessage = _hashTypedData(keccak256(abi.encode(
            keccak256(
                "DepositConfirmation(address sender,address dumbContract,bytes ethscriptionIds,"
                "bytes32 depositId,bytes32 blockHash,uint256 blockNumber)"
            ),
            deposit.sender,
            s().dumbContractAddress,
            keccak256(deposit.ethscriptionIds),
            deposit.depositId,
            deposit.blockHash,
            deposit.blockNumber
        )));

        address signer = hashedMessage.recoverCalldata(deposit.signature);

        require(signer == s().signerAddress, "Invalid signature");
        require(!s().processedDepositIds[deposit.depositId], "Already processed");
        require(s().cancelBlockNumber <= deposit.blockNumber, "Signature canceled");
        require(
            deposit.blockHash == bytes32(0) || blockhash(deposit.blockNumber) == deposit.blockHash,
            "Invalid block number or hash"
        );
        require(deposit.ethscriptionIds.length % 32 == 0 && deposit.ethscriptionIds.length > 0, "Invalid ethscriptions");
        require(
            s().pendingDepositHash[deposit.sender] == keccak256(deposit.ethscriptionIds),
            "Invalid deposits"
        );
        
        s().processedDepositIds[deposit.depositId] = true;
        delete s().pendingDepositHash[deposit.sender];
        
        uint256 bridgeInCount = deposit.ethscriptionIds.length / 32;
        
        bytes memory out = abi.encodePacked(
            'data:application/vnd.facet.tx+json;rule=esip6,{"op":"call","data":{"to":"',
            s().dumbContractAddress.toHexString(),
            '","function":"bridgeIn","args":{"to":"',
            deposit.sender.toHexString(),
            '", "amount":"',
            bridgeInCount.toString(),
            '"}}}'
        );
        
        emit ethscriptions_protocol_CreateEthscription(0x00000000000000000000000000000000000FacE7, string(out));
    }

    function adminConfirmLegacyDeposit(
        address recipient,
        bytes32 depositId
    ) external onlyAdmin {
        require(s().pendingDeposits[recipient].length > 0, "No pending deposits");
        require(!s().processedDepositIds[depositId], "Already processed");
        
        uint256 bridgeInCount = s().pendingDeposits[recipient].length;
        
        delete s().pendingDeposits[recipient];
        s().processedDepositIds[depositId] = true;

        bytes memory out = abi.encodePacked(
            'data:application/vnd.facet.tx+json;rule=esip6,{"op":"call","data":{"to":"',
            s().dumbContractAddress.toHexString(),
            '","function":"bridgeIn","args":{"to":"',
            recipient.toHexString(),
            '", "amount":"',
            bridgeInCount.toString(),
            '"}}}'
        );
        
        emit ethscriptions_protocol_CreateEthscription(0x00000000000000000000000000000000000FacE7, string(out));
    }
    
    function setControlledBridge(ControlledBridge controlledBridge) external onlyAdmin {
        s().controlledBridge = controlledBridge;
    }
    
    function setWithdrawEnabled(bool enabled) external onlyAdmin {
        s().withdrawEnabled = enabled;
    }
    
    function setDepositEnabled(bool enabled) external onlyAdmin {
        s().depositEnabled = enabled;
    }
    
    function setBridgeInLimit(uint16 bridgeInLimit) external onlyAdmin {
        s().bridgeInLimit = bridgeInLimit;
    }

    function enableAllFeatures() external onlyAdmin {
        s().depositEnabled = true;
        s().withdrawEnabled = true;
    }
    
    function disableAllFeatures() external onlyAdmin {
        s().depositEnabled = false;
        s().withdrawEnabled = false;
    }
    
    function cancelSignatures() external onlyAdmin {
        s().cancelBlockNumber = block.number;
    }
    
    function setDumbContract(address dumbContract) external onlyAdmin {
        s().dumbContractAddress = dumbContract;
    }
    
    function setSigner(address signer) external onlyAdmin {
        s().signerAddress = signer;
    }
    
    function setAdmin(address admin) external onlyAdmin {
        s().adminAddress = admin;
    }
    
    function setWithdrawDelay(uint256 withdrawDelay) external onlyAdmin {
        s().withdrawDelay = withdrawDelay;
    }

    function legacyPendingDeposits(address sender) external view returns (bytes32[] memory) {
        return s().pendingDeposits[sender];
    }
    
    fallback() external {
        require(msg.data.length % 32 == 0 && msg.data.length > 0, "Invalid concatenated hashes length");
        require(s().bridgeInLimit > 0, "Bridge in limit not set");
        require(msg.data.length / 32 <= s().bridgeInLimit, "Too many ethscriptions");
        require(s().depositEnabled, "Deposit not enabled");
        
        require(s().pendingDepositHash[msg.sender] == bytes32(0), "Existing pending deposit");
        require(s().pendingDeposits[msg.sender].length == 0, "Existing pending deposit");

        s().pendingDepositHash[msg.sender] = keccak256(msg.data);
    }
    
    function getPendingDepositHash(address sender) external view returns (bytes32) {
        return s().pendingDepositHash[sender];
    }
    
    function getProcessedWithdrawalsPerDeposit(bytes32 ethscriptionId, bytes32 depositId) external view returns (bool) {
        return s().processedWithdrawalsPerDeposit[ethscriptionId][depositId];
    }
    
    function getSigner() external view returns (address) {
        return s().signerAddress;
    }
    
    function getAdmin() external view returns (address) {
        return s().adminAddress;
    }
    
    function getWithdrawDelay() external view returns (uint256) {
        return s().withdrawDelay;
    }
    
    function getDumbContract() external view returns (address) {
        return s().dumbContractAddress;
    }
    
    function getCancelBlockNumber() external view returns (uint256) {
        return s().cancelBlockNumber;
    }
    
    function getDepositEnabled() external view returns (bool) {
        return s().depositEnabled;
    }
    
    function getBridgeInLimit() external view returns (uint16) {
        return s().bridgeInLimit;
    }
    
    function getWithdrawalEnabled() external view returns (bool) {
        return s().depositEnabled;
    }
    
    function processedWithdraws(bytes32 withdrawalId) external view returns (bool) {
        return s().processedWithdrawalIds[withdrawalId];
    }
    
    function processedDepositIds(bytes32 depositId) external view returns (bool) {
        return s().processedDepositIds[depositId];
    }

    function _domainNameAndVersion() 
        internal
        pure
        override
        returns (string memory name, string memory version)
    {
        name = "Facet Ethscription ERC20 Bridge";
        version = "4";
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice The address and bytecode of the canonical ERC1967Factory deployment.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/ERC1967FactoryLib.sol)
/// @author jtriley-eth (https://github.com/jtriley-eth/minimum-viable-proxy)
///
/// @dev The canonical ERC1967Factory is deployed permissionlessly via
/// 0age's ImmutableCreate2Factory located at 0x0000000000FFe8B47B3e2130213B802212439497.
///
/// `ADDRESS = immutableCreate2Factory.safeCreate2(SALT, INITCODE)`
///
/// If the canonical ERC1967Factory has not been deployed on your EVM chain of choice,
/// please feel free to deploy via 0age's ImmutableCreate2Factory.
///
/// If 0age's ImmutableCreate2Factory has not been deployed on your EVM chain of choice,
/// please refer to 0age's ImmutableCreate2Factory deployment instructions at:
/// https://github.com/ProjectOpenSea/seaport/blob/main/docs/Deployment.md
///
/// Contract verification:
/// - Source code:
///   https://github.com/Vectorized/solady/blob/5212e50fef1f2ff1b1b5e03a5d276a0d23c02713/src/utils/ERC1967Factory.sol
///   (The EXACT source code is required. Use the file at the commit instead of the latest copy.)
/// - Optimization Enabled: Yes with 1000000 runs
/// - Compiler Version: v0.8.19+commit.7dd6d404
/// - Other Settings: default evmVersion, MIT license
library ERC1967FactoryConstants {
    /// @dev The canonical ERC1967Factory address for EVM chains.
    address internal constant ADDRESS = 0x0000000000006396FF2a80c067f99B3d2Ab4Df24;

    /// @dev The canonical ERC1967Factory bytecode for EVM chains.
    /// Useful for forge tests:
    /// `vm.etch(ADDRESS, BYTECODE)`.
    bytes internal constant BYTECODE =
        hex"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";

    /// @dev The initcode used to deploy the canonical ERC1967Factory.
    bytes internal constant INITCODE = abi.encodePacked(
        hex"608060405234801561001057600080fd5b506107f6806100206000396000f3fe", BYTECODE
    );

    /// @dev For deterministic deployment via 0age's ImmutableCreate2Factory.
    bytes32 internal constant SALT =
        0x0000000000000000000000000000000000000000e75e4f228818c80007508f33;
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Library for converting numbers into strings and other string operations.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/LibString.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/LibString.sol)
///
/// Note:
/// For performance and bytecode compactness, most of the string operations are restricted to
/// byte strings (7-bit ASCII), except where otherwise specified.
/// Usage of byte string operations on charsets with runes spanning two or more bytes
/// can lead to undefined behavior.
library LibString {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                        CUSTOM ERRORS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The length of the output is too small to contain all the hex digits.
    error HexLengthInsufficient();

    /// @dev The length of the string is more than 32 bytes.
    error TooBigForSmallString();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The constant returned when the `search` is not found in the string.
    uint256 internal constant NOT_FOUND = type(uint256).max;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     DECIMAL OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the base 10 decimal representation of `value`.
    function toString(uint256 value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            // The maximum value of a uint256 contains 78 digits (1 byte per digit), but
            // we allocate 0xa0 bytes to keep the free memory pointer 32-byte word aligned.
            // We will need 1 word for the trailing zeros padding, 1 word for the length,
            // and 3 words for a maximum of 78 digits.
            str := add(mload(0x40), 0x80)
            // Update the free memory pointer to allocate.
            mstore(0x40, add(str, 0x20))
            // Zeroize the slot after the string.
            mstore(str, 0)

            // Cache the end of the memory to calculate the length later.
            let end := str

            let w := not(0) // Tsk.
            // 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 temp := value } 1 {} {
                str := add(str, w) // `sub(str, 1)`.
                // Write the character to the pointer.
                // The ASCII index of the '0' character is 48.
                mstore8(str, add(48, mod(temp, 10)))
                // Keep dividing `temp` until zero.
                temp := div(temp, 10)
                if iszero(temp) { break }
            }

            let length := sub(end, str)
            // Move the pointer 32 bytes leftwards to make room for the length.
            str := sub(str, 0x20)
            // Store the length.
            mstore(str, length)
        }
    }

    /// @dev Returns the base 10 decimal representation of `value`.
    function toString(int256 value) internal pure returns (string memory str) {
        if (value >= 0) {
            return toString(uint256(value));
        }
        unchecked {
            str = toString(~uint256(value) + 1);
        }
        /// @solidity memory-safe-assembly
        assembly {
            // We still have some spare memory space on the left,
            // as we have allocated 3 words (96 bytes) for up to 78 digits.
            let length := mload(str) // Load the string length.
            mstore(str, 0x2d) // Store the '-' character.
            str := sub(str, 1) // Move back the string pointer by a byte.
            mstore(str, add(length, 1)) // Update the string length.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   HEXADECIMAL OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the hexadecimal representation of `value`,
    /// left-padded to an input length of `length` bytes.
    /// The output is prefixed with "0x" encoded using 2 hexadecimal digits per byte,
    /// giving a total length of `length * 2 + 2` bytes.
    /// Reverts if `length` is too small for the output to contain all the digits.
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value, length);
        /// @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`,
    /// left-padded to an input length of `length` bytes.
    /// The output is prefixed with "0x" encoded using 2 hexadecimal digits per byte,
    /// giving a total length of `length * 2` bytes.
    /// Reverts if `length` is too small for the output to contain all the digits.
    function toHexStringNoPrefix(uint256 value, uint256 length)
        internal
        pure
        returns (string memory str)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // We need 0x20 bytes for the trailing zeros padding, `length * 2` bytes
            // for the digits, 0x02 bytes for the prefix, and 0x20 bytes for the length.
            // We add 0x20 to the total and round down to a multiple of 0x20.
            // (0x20 + 0x20 + 0x02 + 0x20) = 0x62.
            str := add(mload(0x40), and(add(shl(1, length), 0x42), not(0x1f)))
            // Allocate the memory.
            mstore(0x40, add(str, 0x20))
            // Zeroize the slot after the string.
            mstore(str, 0)

            // Cache the end to calculate the length later.
            let end := str
            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let start := sub(str, add(length, length))
            let w := not(1) // Tsk.
            let temp := 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 {} 1 {} {
                str := add(str, w) // `sub(str, 2)`.
                mstore8(add(str, 1), mload(and(temp, 15)))
                mstore8(str, mload(and(shr(4, temp), 15)))
                temp := shr(8, temp)
                if iszero(xor(str, start)) { break }
            }

            if temp {
                mstore(0x00, 0x2194895a) // `HexLengthInsufficient()`.
                revert(0x1c, 0x04)
            }

            // Compute the string's length.
            let strLength := sub(end, str)
            // Move the pointer and write the length.
            str := sub(str, 0x20)
            mstore(str, strLength)
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x" and encoded using 2 hexadecimal digits per byte.
    /// As address are 20 bytes long, the output will left-padded to have
    /// a length of `20 * 2 + 2` bytes.
    function toHexString(uint256 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 prefixed with "0x".
    /// The output excludes leading "0" from the `toHexString` output.
    /// `0x00: "0x0", 0x01: "0x1", 0x12: "0x12", 0x123: "0x123"`.
    function toMinimalHexString(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let o := eq(byte(0, mload(add(str, 0x20))), 0x30) // Whether leading zero is present.
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(add(str, o), 0x3078) // Write the "0x" prefix, accounting for leading zero.
            str := sub(add(str, o), 2) // Move the pointer, accounting for leading zero.
            mstore(str, sub(strLength, o)) // Write the length, accounting for leading zero.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output excludes leading "0" from the `toHexStringNoPrefix` output.
    /// `0x00: "0", 0x01: "1", 0x12: "12", 0x123: "123"`.
    function toMinimalHexStringNoPrefix(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let o := eq(byte(0, mload(add(str, 0x20))), 0x30) // Whether leading zero is present.
            let strLength := mload(str) // Get the length.
            str := add(str, o) // Move the pointer, accounting for leading zero.
            mstore(str, sub(strLength, o)) // Write the length, accounting for leading zero.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is encoded using 2 hexadecimal digits per byte.
    /// As address are 20 bytes long, the output will left-padded to have
    /// a length of `20 * 2` bytes.
    function toHexStringNoPrefix(uint256 value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            // We need 0x20 bytes for the trailing zeros padding, 0x20 bytes for the length,
            // 0x02 bytes for the prefix, and 0x40 bytes for the digits.
            // The next multiple of 0x20 above (0x20 + 0x20 + 0x02 + 0x40) is 0xa0.
            str := add(mload(0x40), 0x80)
            // Allocate the memory.
            mstore(0x40, add(str, 0x20))
            // Zeroize the slot after the string.
            mstore(str, 0)

            // Cache the end to calculate the length later.
            let end := str
            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let w := not(1) // Tsk.
            // 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 temp := value } 1 {} {
                str := add(str, w) // `sub(str, 2)`.
                mstore8(add(str, 1), mload(and(temp, 15)))
                mstore8(str, mload(and(shr(4, temp), 15)))
                temp := shr(8, temp)
                if iszero(temp) { break }
            }

            // Compute the string's length.
            let strLength := sub(end, str)
            // Move the pointer and write the length.
            str := sub(str, 0x20)
            mstore(str, strLength)
        }
    }

    /// @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.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   RUNE STRING OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the number of UTF characters in the string.
    function runeCount(string memory s) internal pure returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            if mload(s) {
                mstore(0x00, div(not(0), 255))
                mstore(0x20, 0x0202020202020202020202020202020202020202020202020303030304040506)
                let o := add(s, 0x20)
                let end := add(o, mload(s))
                for { result := 1 } 1 { result := add(result, 1) } {
                    o := add(o, byte(0, mload(shr(250, mload(o)))))
                    if iszero(lt(o, end)) { break }
                }
            }
        }
    }

    /// @dev Returns if this string is a 7-bit ASCII string.
    /// (i.e. all characters codes are in [0..127])
    function is7BitASCII(string memory s) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            let mask := shl(7, div(not(0), 255))
            result := 1
            let n := mload(s)
            if n {
                let o := add(s, 0x20)
                let end := add(o, n)
                let last := mload(end)
                mstore(end, 0)
                for {} 1 {} {
                    if and(mask, mload(o)) {
                        result := 0
                        break
                    }
                    o := add(o, 0x20)
                    if iszero(lt(o, end)) { break }
                }
                mstore(end, last)
            }
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   BYTE STRING OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    // For performance and bytecode compactness, byte string operations are restricted
    // to 7-bit ASCII strings. All offsets are byte offsets, not UTF character offsets.
    // Usage of byte string operations on charsets with runes spanning two or more bytes
    // can lead to undefined behavior.

    /// @dev Returns `subject` all occurrences of `search` replaced with `replacement`.
    function replace(string memory subject, string memory search, string memory replacement)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            let searchLength := mload(search)
            let replacementLength := mload(replacement)

            subject := add(subject, 0x20)
            search := add(search, 0x20)
            replacement := add(replacement, 0x20)
            result := add(mload(0x40), 0x20)

            let subjectEnd := add(subject, subjectLength)
            if iszero(gt(searchLength, subjectLength)) {
                let subjectSearchEnd := add(sub(subjectEnd, searchLength), 1)
                let h := 0
                if iszero(lt(searchLength, 0x20)) { h := keccak256(search, searchLength) }
                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(search)
                for {} 1 {} {
                    let t := mload(subject)
                    // Whether the first `searchLength % 32` bytes of
                    // `subject` and `search` matches.
                    if iszero(shr(m, xor(t, s))) {
                        if h {
                            if iszero(eq(keccak256(subject, searchLength), h)) {
                                mstore(result, t)
                                result := add(result, 1)
                                subject := add(subject, 1)
                                if iszero(lt(subject, subjectSearchEnd)) { break }
                                continue
                            }
                        }
                        // Copy the `replacement` one word at a time.
                        for { let o := 0 } 1 {} {
                            mstore(add(result, o), mload(add(replacement, o)))
                            o := add(o, 0x20)
                            if iszero(lt(o, replacementLength)) { break }
                        }
                        result := add(result, replacementLength)
                        subject := add(subject, searchLength)
                        if searchLength {
                            if iszero(lt(subject, subjectSearchEnd)) { break }
                            continue
                        }
                    }
                    mstore(result, t)
                    result := add(result, 1)
                    subject := add(subject, 1)
                    if iszero(lt(subject, subjectSearchEnd)) { break }
                }
            }

            let resultRemainder := result
            result := add(mload(0x40), 0x20)
            let k := add(sub(resultRemainder, result), sub(subjectEnd, subject))
            // Copy the rest of the string one word at a time.
            for {} lt(subject, subjectEnd) {} {
                mstore(resultRemainder, mload(subject))
                resultRemainder := add(resultRemainder, 0x20)
                subject := add(subject, 0x20)
            }
            result := sub(result, 0x20)
            let last := add(add(result, 0x20), k) // Zeroize the slot after the string.
            mstore(last, 0)
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
            mstore(result, k) // Store the length.
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from left to right, starting from `from`.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function indexOf(string memory subject, string memory search, uint256 from)
        internal
        pure
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            for { let subjectLength := mload(subject) } 1 {} {
                if iszero(mload(search)) {
                    if iszero(gt(from, subjectLength)) {
                        result := from
                        break
                    }
                    result := subjectLength
                    break
                }
                let searchLength := mload(search)
                let subjectStart := add(subject, 0x20)

                result := not(0) // Initialize to `NOT_FOUND`.

                subject := add(subjectStart, from)
                let end := add(sub(add(subjectStart, subjectLength), searchLength), 1)

                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(add(search, 0x20))

                if iszero(and(lt(subject, end), lt(from, subjectLength))) { break }

                if iszero(lt(searchLength, 0x20)) {
                    for { let h := keccak256(add(search, 0x20), searchLength) } 1 {} {
                        if iszero(shr(m, xor(mload(subject), s))) {
                            if eq(keccak256(subject, searchLength), h) {
                                result := sub(subject, subjectStart)
                                break
                            }
                        }
                        subject := add(subject, 1)
                        if iszero(lt(subject, end)) { break }
                    }
                    break
                }
                for {} 1 {} {
                    if iszero(shr(m, xor(mload(subject), s))) {
                        result := sub(subject, subjectStart)
                        break
                    }
                    subject := add(subject, 1)
                    if iszero(lt(subject, end)) { break }
                }
                break
            }
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from left to right.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function indexOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256 result)
    {
        result = indexOf(subject, search, 0);
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from right to left, starting from `from`.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function lastIndexOf(string memory subject, string memory search, uint256 from)
        internal
        pure
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            for {} 1 {} {
                result := not(0) // Initialize to `NOT_FOUND`.
                let searchLength := mload(search)
                if gt(searchLength, mload(subject)) { break }
                let w := result

                let fromMax := sub(mload(subject), searchLength)
                if iszero(gt(fromMax, from)) { from := fromMax }

                let end := add(add(subject, 0x20), w)
                subject := add(add(subject, 0x20), from)
                if iszero(gt(subject, end)) { break }
                // As this function is not too often used,
                // we shall simply use keccak256 for smaller bytecode size.
                for { let h := keccak256(add(search, 0x20), searchLength) } 1 {} {
                    if eq(keccak256(subject, searchLength), h) {
                        result := sub(subject, add(end, 1))
                        break
                    }
                    subject := add(subject, w) // `sub(subject, 1)`.
                    if iszero(gt(subject, end)) { break }
                }
                break
            }
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from right to left.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function lastIndexOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256 result)
    {
        result = lastIndexOf(subject, search, uint256(int256(-1)));
    }

    /// @dev Returns true if `search` is found in `subject`, false otherwise.
    function contains(string memory subject, string memory search) internal pure returns (bool) {
        return indexOf(subject, search) != NOT_FOUND;
    }

    /// @dev Returns whether `subject` starts with `search`.
    function startsWith(string memory subject, string memory search)
        internal
        pure
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let searchLength := mload(search)
            // Just using keccak256 directly is actually cheaper.
            // forgefmt: disable-next-item
            result := and(
                iszero(gt(searchLength, mload(subject))),
                eq(
                    keccak256(add(subject, 0x20), searchLength),
                    keccak256(add(search, 0x20), searchLength)
                )
            )
        }
    }

    /// @dev Returns whether `subject` ends with `search`.
    function endsWith(string memory subject, string memory search)
        internal
        pure
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let searchLength := mload(search)
            let subjectLength := mload(subject)
            // Whether `search` is not longer than `subject`.
            let withinRange := iszero(gt(searchLength, subjectLength))
            // Just using keccak256 directly is actually cheaper.
            // forgefmt: disable-next-item
            result := and(
                withinRange,
                eq(
                    keccak256(
                        // `subject + 0x20 + max(subjectLength - searchLength, 0)`.
                        add(add(subject, 0x20), mul(withinRange, sub(subjectLength, searchLength))),
                        searchLength
                    ),
                    keccak256(add(search, 0x20), searchLength)
                )
            )
        }
    }

    /// @dev Returns `subject` repeated `times`.
    function repeat(string memory subject, uint256 times)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            if iszero(or(iszero(times), iszero(subjectLength))) {
                subject := add(subject, 0x20)
                result := mload(0x40)
                let output := add(result, 0x20)
                for {} 1 {} {
                    // Copy the `subject` one word at a time.
                    for { let o := 0 } 1 {} {
                        mstore(add(output, o), mload(add(subject, o)))
                        o := add(o, 0x20)
                        if iszero(lt(o, subjectLength)) { break }
                    }
                    output := add(output, subjectLength)
                    times := sub(times, 1)
                    if iszero(times) { break }
                }
                mstore(output, 0) // Zeroize the slot after the string.
                let resultLength := sub(output, add(result, 0x20))
                mstore(result, resultLength) // Store the length.
                // Allocate the memory.
                mstore(0x40, add(result, add(resultLength, 0x20)))
            }
        }
    }

    /// @dev Returns a copy of `subject` sliced from `start` to `end` (exclusive).
    /// `start` and `end` are byte offsets.
    function slice(string memory subject, uint256 start, uint256 end)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            if iszero(gt(subjectLength, end)) { end := subjectLength }
            if iszero(gt(subjectLength, start)) { start := subjectLength }
            if lt(start, end) {
                result := mload(0x40)
                let resultLength := sub(end, start)
                mstore(result, resultLength)
                subject := add(subject, start)
                let w := not(0x1f)
                // Copy the `subject` one word at a time, backwards.
                for { let o := and(add(resultLength, 0x1f), w) } 1 {} {
                    mstore(add(result, o), mload(add(subject, o)))
                    o := add(o, w) // `sub(o, 0x20)`.
                    if iszero(o) { break }
                }
                // Zeroize the slot after the string.
                mstore(add(add(result, 0x20), resultLength), 0)
                // Allocate memory for the length and the bytes,
                // rounded up to a multiple of 32.
                mstore(0x40, add(result, and(add(resultLength, 0x3f), w)))
            }
        }
    }

    /// @dev Returns a copy of `subject` sliced from `start` to the end of the string.
    /// `start` is a byte offset.
    function slice(string memory subject, uint256 start)
        internal
        pure
        returns (string memory result)
    {
        result = slice(subject, start, uint256(int256(-1)));
    }

    /// @dev Returns all the indices of `search` in `subject`.
    /// The indices are byte offsets.
    function indicesOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256[] memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            let searchLength := mload(search)

            if iszero(gt(searchLength, subjectLength)) {
                subject := add(subject, 0x20)
                search := add(search, 0x20)
                result := add(mload(0x40), 0x20)

                let subjectStart := subject
                let subjectSearchEnd := add(sub(add(subject, subjectLength), searchLength), 1)
                let h := 0
                if iszero(lt(searchLength, 0x20)) { h := keccak256(search, searchLength) }
                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(search)
                for {} 1 {} {
                    let t := mload(subject)
                    // Whether the first `searchLength % 32` bytes of
                    // `subject` and `search` matches.
                    if iszero(shr(m, xor(t, s))) {
                        if h {
                            if iszero(eq(keccak256(subject, searchLength), h)) {
                                subject := add(subject, 1)
                                if iszero(lt(subject, subjectSearchEnd)) { break }
                                continue
                            }
                        }
                        // Append to `result`.
                        mstore(result, sub(subject, subjectStart))
                        result := add(result, 0x20)
                        // Advance `subject` by `searchLength`.
                        subject := add(subject, searchLength)
                        if searchLength {
                            if iszero(lt(subject, subjectSearchEnd)) { break }
                            continue
                        }
                    }
                    subject := add(subject, 1)
                    if iszero(lt(subject, subjectSearchEnd)) { break }
                }
                let resultEnd := result
                // Assign `result` to the free memory pointer.
                result := mload(0x40)
                // Store the length of `result`.
                mstore(result, shr(5, sub(resultEnd, add(result, 0x20))))
                // Allocate memory for result.
                // We allocate one more word, so this array can be recycled for {split}.
                mstore(0x40, add(resultEnd, 0x20))
            }
        }
    }

    /// @dev Returns a arrays of strings based on the `delimiter` inside of the `subject` string.
    function split(string memory subject, string memory delimiter)
        internal
        pure
        returns (string[] memory result)
    {
        uint256[] memory indices = indicesOf(subject, delimiter);
        /// @solidity memory-safe-assembly
        assembly {
            let w := not(0x1f)
            let indexPtr := add(indices, 0x20)
            let indicesEnd := add(indexPtr, shl(5, add(mload(indices), 1)))
            mstore(add(indicesEnd, w), mload(subject))
            mstore(indices, add(mload(indices), 1))
            let prevIndex := 0
            for {} 1 {} {
                let index := mload(indexPtr)
                mstore(indexPtr, 0x60)
                if iszero(eq(index, prevIndex)) {
                    let element := mload(0x40)
                    let elementLength := sub(index, prevIndex)
                    mstore(element, elementLength)
                    // Copy the `subject` one word at a time, backwards.
                    for { let o := and(add(elementLength, 0x1f), w) } 1 {} {
                        mstore(add(element, o), mload(add(add(subject, prevIndex), o)))
                        o := add(o, w) // `sub(o, 0x20)`.
                        if iszero(o) { break }
                    }
                    // Zeroize the slot after the string.
                    mstore(add(add(element, 0x20), elementLength), 0)
                    // Allocate memory for the length and the bytes,
                    // rounded up to a multiple of 32.
                    mstore(0x40, add(element, and(add(elementLength, 0x3f), w)))
                    // Store the `element` into the array.
                    mstore(indexPtr, element)
                }
                prevIndex := add(index, mload(delimiter))
                indexPtr := add(indexPtr, 0x20)
                if iszero(lt(indexPtr, indicesEnd)) { break }
            }
            result := indices
            if iszero(mload(delimiter)) {
                result := add(indices, 0x20)
                mstore(result, sub(mload(indices), 2))
            }
        }
    }

    /// @dev Returns a concatenated string of `a` and `b`.
    /// Cheaper than `string.concat()` and does not de-align the free memory pointer.
    function concat(string memory a, string memory b)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let w := not(0x1f)
            result := mload(0x40)
            let aLength := mload(a)
            // Copy `a` one word at a time, backwards.
            for { let o := and(add(aLength, 0x20), w) } 1 {} {
                mstore(add(result, o), mload(add(a, o)))
                o := add(o, w) // `sub(o, 0x20)`.
                if iszero(o) { break }
            }
            let bLength := mload(b)
            let output := add(result, aLength)
            // Copy `b` one word at a time, backwards.
            for { let o := and(add(bLength, 0x20), w) } 1 {} {
                mstore(add(output, o), mload(add(b, o)))
                o := add(o, w) // `sub(o, 0x20)`.
                if iszero(o) { break }
            }
            let totalLength := add(aLength, bLength)
            let last := add(add(result, 0x20), totalLength)
            // Zeroize the slot after the string.
            mstore(last, 0)
            // Stores the length.
            mstore(result, totalLength)
            // Allocate memory for the length and the bytes,
            // rounded up to a multiple of 32.
            mstore(0x40, and(add(last, 0x1f), w))
        }
    }

    /// @dev Returns a copy of the string in either lowercase or UPPERCASE.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function toCase(string memory subject, bool toUpper)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let length := mload(subject)
            if length {
                result := add(mload(0x40), 0x20)
                subject := add(subject, 1)
                let flags := shl(add(70, shl(5, toUpper)), 0x3ffffff)
                let w := not(0)
                for { let o := length } 1 {} {
                    o := add(o, w)
                    let b := and(0xff, mload(add(subject, o)))
                    mstore8(add(result, o), xor(b, and(shr(b, flags), 0x20)))
                    if iszero(o) { break }
                }
                result := mload(0x40)
                mstore(result, length) // Store the length.
                let last := add(add(result, 0x20), length)
                mstore(last, 0) // Zeroize the slot after the string.
                mstore(0x40, add(last, 0x20)) // Allocate the memory.
            }
        }
    }

    /// @dev Returns a string from a small bytes32 string.
    /// `s` must be null-terminated, or behavior will be undefined.
    function fromSmallString(bytes32 s) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40)
            let n := 0
            for {} byte(n, s) { n := add(n, 1) } {} // Scan for '\0'.
            mstore(result, n)
            let o := add(result, 0x20)
            mstore(o, s)
            mstore(add(o, n), 0)
            mstore(0x40, add(result, 0x40))
        }
    }

    /// @dev Returns the small string, with all bytes after the first null byte zeroized.
    function normalizeSmallString(bytes32 s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            for {} byte(result, s) { result := add(result, 1) } {} // Scan for '\0'.
            mstore(0x00, s)
            mstore(result, 0x00)
            result := mload(0x00)
        }
    }

    /// @dev Returns the string as a normalized null-terminated small string.
    function toSmallString(string memory s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(s)
            if iszero(lt(result, 33)) {
                mstore(0x00, 0xec92f9a3) // `TooBigForSmallString()`.
                revert(0x1c, 0x04)
            }
            result := shl(shl(3, sub(32, result)), mload(add(s, result)))
        }
    }

    /// @dev Returns a lowercased copy of the string.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function lower(string memory subject) internal pure returns (string memory result) {
        result = toCase(subject, false);
    }

    /// @dev Returns an UPPERCASED copy of the string.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function upper(string memory subject) internal pure returns (string memory result) {
        result = toCase(subject, true);
    }

    /// @dev Escapes the string to be used within HTML tags.
    function escapeHTML(string memory s) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            let end := add(s, mload(s))
            result := add(mload(0x40), 0x20)
            // Store the bytes of the packed offsets and strides into the scratch space.
            // `packed = (stride << 5) | offset`. Max offset is 20. Max stride is 6.
            mstore(0x1f, 0x900094)
            mstore(0x08, 0xc0000000a6ab)
            // Store "&quot;&amp;&#39;&lt;&gt;" into the scratch space.
            mstore(0x00, shl(64, 0x2671756f743b26616d703b262333393b266c743b2667743b))
            for {} iszero(eq(s, end)) {} {
                s := add(s, 1)
                let c := and(mload(s), 0xff)
                // Not in `["\"","'","&","<",">"]`.
                if iszero(and(shl(c, 1), 0x500000c400000000)) {
                    mstore8(result, c)
                    result := add(result, 1)
                    continue
                }
                let t := shr(248, mload(c))
                mstore(result, mload(and(t, 0x1f)))
                result := add(result, shr(5, t))
            }
            let last := result
            mstore(last, 0) // Zeroize the slot after the string.
            result := mload(0x40)
            mstore(result, sub(last, add(result, 0x20))) // Store the length.
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
        }
    }

    /// @dev Escapes the string to be used within double-quotes in a JSON.
    /// If `addDoubleQuotes` is true, the result will be enclosed in double-quotes.
    function escapeJSON(string memory s, bool addDoubleQuotes)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let end := add(s, mload(s))
            result := add(mload(0x40), 0x20)
            if addDoubleQuotes {
                mstore8(result, 34)
                result := add(1, result)
            }
            // Store "\\u0000" in scratch space.
            // Store "0123456789abcdef" in scratch space.
            // Also, store `{0x08:"b", 0x09:"t", 0x0a:"n", 0x0c:"f", 0x0d:"r"}`.
            // into the scratch space.
            mstore(0x15, 0x5c75303030303031323334353637383961626364656662746e006672)
            // Bitmask for detecting `["\"","\\"]`.
            let e := or(shl(0x22, 1), shl(0x5c, 1))
            for {} iszero(eq(s, end)) {} {
                s := add(s, 1)
                let c := and(mload(s), 0xff)
                if iszero(lt(c, 0x20)) {
                    if iszero(and(shl(c, 1), e)) {
                        // Not in `["\"","\\"]`.
                        mstore8(result, c)
                        result := add(result, 1)
                        continue
                    }
                    mstore8(result, 0x5c) // "\\".
                    mstore8(add(result, 1), c)
                    result := add(result, 2)
                    continue
                }
                if iszero(and(shl(c, 1), 0x3700)) {
                    // Not in `["\b","\t","\n","\f","\d"]`.
                    mstore8(0x1d, mload(shr(4, c))) // Hex value.
                    mstore8(0x1e, mload(and(c, 15))) // Hex value.
                    mstore(result, mload(0x19)) // "\\u00XX".
                    result := add(result, 6)
                    continue
                }
                mstore8(result, 0x5c) // "\\".
                mstore8(add(result, 1), mload(add(c, 8)))
                result := add(result, 2)
            }
            if addDoubleQuotes {
                mstore8(result, 34)
                result := add(1, result)
            }
            let last := result
            mstore(last, 0) // Zeroize the slot after the string.
            result := mload(0x40)
            mstore(result, sub(last, add(result, 0x20))) // Store the length.
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
        }
    }

    /// @dev Escapes the string to be used within double-quotes in a JSON.
    function escapeJSON(string memory s) internal pure returns (string memory result) {
        result = escapeJSON(s, false);
    }

    /// @dev Returns whether `a` equals `b`.
    function eq(string memory a, string memory b) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := eq(keccak256(add(a, 0x20), mload(a)), keccak256(add(b, 0x20), mload(b)))
        }
    }

    /// @dev Returns whether `a` equals `b`, where `b` is a null-terminated small string.
    function eqs(string memory a, bytes32 b) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            // These should be evaluated on compile time, as far as possible.
            let m := not(shl(7, div(not(iszero(b)), 255))) // `0x7f7f ...`.
            let x := not(or(m, or(b, add(m, and(b, m)))))
            let r := shl(7, iszero(iszero(shr(128, x))))
            r := or(r, shl(6, iszero(iszero(shr(64, 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))))
            // forgefmt: disable-next-item
            result := gt(eq(mload(a), add(iszero(x), xor(31, shr(3, r)))),
                xor(shr(add(8, r), b), shr(add(8, r), mload(add(a, 0x20)))))
        }
    }

    /// @dev Packs a single string with its length into a single word.
    /// Returns `bytes32(0)` if the length is zero or greater than 31.
    function packOne(string memory a) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            // We don't need to zero right pad the string,
            // since this is our own custom non-standard packing scheme.
            result :=
                mul(
                    // Load the length and the bytes.
                    mload(add(a, 0x1f)),
                    // `length != 0 && length < 32`. Abuses underflow.
                    // Assumes that the length is valid and within the block gas limit.
                    lt(sub(mload(a), 1), 0x1f)
                )
        }
    }

    /// @dev Unpacks a string packed using {packOne}.
    /// Returns the empty string if `packed` is `bytes32(0)`.
    /// If `packed` is not an output of {packOne}, the output behavior is undefined.
    function unpackOne(bytes32 packed) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Grab the free memory pointer.
            result := mload(0x40)
            // Allocate 2 words (1 for the length, 1 for the bytes).
            mstore(0x40, add(result, 0x40))
            // Zeroize the length slot.
            mstore(result, 0)
            // Store the length and bytes.
            mstore(add(result, 0x1f), packed)
            // Right pad with zeroes.
            mstore(add(add(result, 0x20), mload(result)), 0)
        }
    }

    /// @dev Packs two strings with their lengths into a single word.
    /// Returns `bytes32(0)` if combined length is zero or greater than 30.
    function packTwo(string memory a, string memory b) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            let aLength := mload(a)
            // We don't need to zero right pad the strings,
            // since this is our own custom non-standard packing scheme.
            result :=
                mul(
                    // Load the length and the bytes of `a` and `b`.
                    or(
                        shl(shl(3, sub(0x1f, aLength)), mload(add(a, aLength))),
                        mload(sub(add(b, 0x1e), aLength))
                    ),
                    // `totalLength != 0 && totalLength < 31`. Abuses underflow.
                    // Assumes that the lengths are valid and within the block gas limit.
                    lt(sub(add(aLength, mload(b)), 1), 0x1e)
                )
        }
    }

    /// @dev Unpacks strings packed using {packTwo}.
    /// Returns the empty strings if `packed` is `bytes32(0)`.
    /// If `packed` is not an output of {packTwo}, the output behavior is undefined.
    function unpackTwo(bytes32 packed)
        internal
        pure
        returns (string memory resultA, string memory resultB)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Grab the free memory pointer.
            resultA := mload(0x40)
            resultB := add(resultA, 0x40)
            // Allocate 2 words for each string (1 for the length, 1 for the byte). Total 4 words.
            mstore(0x40, add(resultB, 0x40))
            // Zeroize the length slots.
            mstore(resultA, 0)
            mstore(resultB, 0)
            // Store the lengths and bytes.
            mstore(add(resultA, 0x1f), packed)
            mstore(add(resultB, 0x1f), mload(add(add(resultA, 0x20), mload(resultA))))
            // Right pad with zeroes.
            mstore(add(add(resultA, 0x20), mload(resultA)), 0)
            mstore(add(add(resultB, 0x20), mload(resultB)), 0)
        }
    }

    /// @dev Directly returns `a` without copying.
    function directReturn(string memory a) internal pure {
        assembly {
            // Assumes that the string does not start from the scratch space.
            let retStart := sub(a, 0x20)
            let retSize := add(mload(a), 0x40)
            // Right pad with zeroes. Just in case the string is produced
            // by a method that doesn't zero right pad.
            mstore(add(retStart, retSize), 0)
            // Store the return offset.
            mstore(retStart, 0x20)
            // End the transaction, returning the string.
            return(retStart, retSize)
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Contract for EIP-712 typed structured data hashing and signing.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/EIP712.sol)
/// @author Modified from Solbase (https://github.com/Sol-DAO/solbase/blob/main/src/utils/EIP712.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/EIP712.sol)
///
/// @dev Note, this implementation:
/// - Uses `address(this)` for the `verifyingContract` field.
/// - Does NOT use the optional EIP-712 salt.
/// - Does NOT use any EIP-712 extensions.
/// This is for simplicity and to save gas.
/// If you need to customize, please fork / modify accordingly.
abstract contract EIP712 {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  CONSTANTS AND IMMUTABLES                  */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev `keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")`.
    bytes32 internal constant _DOMAIN_TYPEHASH =
        0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f;

    uint256 private immutable _cachedThis;
    uint256 private immutable _cachedChainId;
    bytes32 private immutable _cachedNameHash;
    bytes32 private immutable _cachedVersionHash;
    bytes32 private immutable _cachedDomainSeparator;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                        CONSTRUCTOR                         */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Cache the hashes for cheaper runtime gas costs.
    /// In the case of upgradeable contracts (i.e. proxies),
    /// or if the chain id changes due to a hard fork,
    /// the domain separator will be seamlessly calculated on-the-fly.
    constructor() {
        _cachedThis = uint256(uint160(address(this)));
        _cachedChainId = block.chainid;

        string memory name;
        string memory version;
        if (!_domainNameAndVersionMayChange()) (name, version) = _domainNameAndVersion();
        bytes32 nameHash = _domainNameAndVersionMayChange() ? bytes32(0) : keccak256(bytes(name));
        bytes32 versionHash =
            _domainNameAndVersionMayChange() ? bytes32(0) : keccak256(bytes(version));
        _cachedNameHash = nameHash;
        _cachedVersionHash = versionHash;

        bytes32 separator;
        if (!_domainNameAndVersionMayChange()) {
            /// @solidity memory-safe-assembly
            assembly {
                let m := mload(0x40) // Load the free memory pointer.
                mstore(m, _DOMAIN_TYPEHASH)
                mstore(add(m, 0x20), nameHash)
                mstore(add(m, 0x40), versionHash)
                mstore(add(m, 0x60), chainid())
                mstore(add(m, 0x80), address())
                separator := keccak256(m, 0xa0)
            }
        }
        _cachedDomainSeparator = separator;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   FUNCTIONS TO OVERRIDE                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Please override this function to return the domain name and version.
    /// ```
    ///     function _domainNameAndVersion()
    ///         internal
    ///         pure
    ///         virtual
    ///         returns (string memory name, string memory version)
    ///     {
    ///         name = "Solady";
    ///         version = "1";
    ///     }
    /// ```
    ///
    /// Note: If the returned result may change after the contract has been deployed,
    /// you must override `_domainNameAndVersionMayChange()` to return true.
    function _domainNameAndVersion()
        internal
        view
        virtual
        returns (string memory name, string memory version);

    /// @dev Returns if `_domainNameAndVersion()` may change
    /// after the contract has been deployed (i.e. after the constructor).
    /// Default: false.
    function _domainNameAndVersionMayChange() internal pure virtual returns (bool result) {}

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     HASHING OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the EIP-712 domain separator.
    function _domainSeparator() internal view virtual returns (bytes32 separator) {
        if (_domainNameAndVersionMayChange()) {
            separator = _buildDomainSeparator();
        } else {
            separator = _cachedDomainSeparator;
            if (_cachedDomainSeparatorInvalidated()) separator = _buildDomainSeparator();
        }
    }

    /// @dev Returns the hash of the fully encoded EIP-712 message for this domain,
    /// given `structHash`, as defined in
    /// https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct.
    ///
    /// The hash can be used together with {ECDSA-recover} to obtain the signer of a message:
    /// ```
    ///     bytes32 digest = _hashTypedData(keccak256(abi.encode(
    ///         keccak256("Mail(address to,string contents)"),
    ///         mailTo,
    ///         keccak256(bytes(mailContents))
    ///     )));
    ///     address signer = ECDSA.recover(digest, signature);
    /// ```
    function _hashTypedData(bytes32 structHash) internal view virtual returns (bytes32 digest) {
        // We will use `digest` to store the domain separator to save a bit of gas.
        if (_domainNameAndVersionMayChange()) {
            digest = _buildDomainSeparator();
        } else {
            digest = _cachedDomainSeparator;
            if (_cachedDomainSeparatorInvalidated()) digest = _buildDomainSeparator();
        }
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the digest.
            mstore(0x00, 0x1901000000000000) // Store "\x19\x01".
            mstore(0x1a, digest) // Store the domain separator.
            mstore(0x3a, structHash) // Store the struct hash.
            digest := keccak256(0x18, 0x42)
            // Restore the part of the free memory slot that was overwritten.
            mstore(0x3a, 0)
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                    EIP-5267 OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev See: https://eips.ethereum.org/EIPS/eip-5267
    function eip712Domain()
        public
        view
        virtual
        returns (
            bytes1 fields,
            string memory name,
            string memory version,
            uint256 chainId,
            address verifyingContract,
            bytes32 salt,
            uint256[] memory extensions
        )
    {
        fields = hex"0f"; // `0b01111`.
        (name, version) = _domainNameAndVersion();
        chainId = block.chainid;
        verifyingContract = address(this);
        salt = salt; // `bytes32(0)`.
        extensions = extensions; // `new uint256[](0)`.
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      PRIVATE HELPERS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the EIP-712 domain separator.
    function _buildDomainSeparator() private view returns (bytes32 separator) {
        // We will use `separator` to store the name hash to save a bit of gas.
        bytes32 versionHash;
        if (_domainNameAndVersionMayChange()) {
            (string memory name, string memory version) = _domainNameAndVersion();
            separator = keccak256(bytes(name));
            versionHash = keccak256(bytes(version));
        } else {
            separator = _cachedNameHash;
            versionHash = _cachedVersionHash;
        }
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Load the free memory pointer.
            mstore(m, _DOMAIN_TYPEHASH)
            mstore(add(m, 0x20), separator) // Name hash.
            mstore(add(m, 0x40), versionHash)
            mstore(add(m, 0x60), chainid())
            mstore(add(m, 0x80), address())
            separator := keccak256(m, 0xa0)
        }
    }

    /// @dev Returns if the cached domain separator has been invalidated.
    function _cachedDomainSeparatorInvalidated() private view returns (bool result) {
        uint256 cachedChainId = _cachedChainId;
        uint256 cachedThis = _cachedThis;
        /// @solidity memory-safe-assembly
        assembly {
            result := iszero(and(eq(chainid(), cachedChainId), eq(address(), cachedThis)))
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Gas optimized ECDSA wrapper.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/ECDSA.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/ECDSA.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/ECDSA.sol)
///
/// @dev Note:
/// - The recovery functions use the ecrecover precompile (0x1).
/// - As of Solady version 0.0.68, the `recover` variants will revert upon recovery failure.
///   This is for more safety by default.
///   Use the `tryRecover` variants if you need to get the zero address back
///   upon recovery failure instead.
/// - As of Solady version 0.0.134, all `bytes signature` variants accept both
///   regular 65-byte `(r, s, v)` and EIP-2098 `(r, vs)` short form signatures.
///   See: https://eips.ethereum.org/EIPS/eip-2098
///   This is for calldata efficiency on smart accounts prevalent on L2s.
///
/// WARNING! Do NOT use signatures as unique identifiers:
/// - Use a nonce in the digest to prevent replay attacks on the same contract.
/// - Use EIP-712 for the digest to prevent replay attacks across different chains and contracts.
///   EIP-712 also enables readable signing of typed data for better user safety.
/// This implementation does NOT check if a signature is non-malleable.
library ECDSA {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                        CUSTOM ERRORS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The signature is invalid.
    error InvalidSignature();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                    RECOVERY OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function recover(bytes32 hash, bytes memory signature) internal view returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            for {} 1 {} {
                mstore(0x00, hash)
                mstore(0x40, mload(add(signature, 0x20))) // `r`.
                if eq(mload(signature), 64) {
                    let vs := mload(add(signature, 0x40))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(mload(signature), 65) {
                    mstore(0x20, byte(0, mload(add(signature, 0x60)))) // `v`.
                    mstore(0x60, mload(add(signature, 0x40))) // `s`.
                    break
                }
                result := 0
                break
            }
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        result, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function recoverCalldata(bytes32 hash, bytes calldata signature)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            for {} 1 {} {
                if eq(signature.length, 64) {
                    let vs := calldataload(add(signature.offset, 0x20))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x40, calldataload(signature.offset)) // `r`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(signature.length, 65) {
                    mstore(0x20, byte(0, calldataload(add(signature.offset, 0x40)))) // `v`.
                    calldatacopy(0x40, signature.offset, 0x40) // Copy `r` and `s`.
                    break
                }
                result := 0
                break
            }
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        result, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the EIP-2098 short form signature defined by `r` and `vs`.
    function recover(bytes32 hash, bytes32 r, bytes32 vs) internal view returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, add(shr(255, vs), 27)) // `v`.
            mstore(0x40, r)
            mstore(0x60, shr(1, shl(1, vs))) // `s`.
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        1, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the signature defined by `v`, `r`, `s`.
    function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, and(v, 0xff))
            mstore(0x40, r)
            mstore(0x60, s)
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        1, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   TRY-RECOVER OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    // WARNING!
    // These functions will NOT revert upon recovery failure.
    // Instead, they will return the zero address upon recovery failure.
    // It is critical that the returned address is NEVER compared against
    // a zero address (e.g. an uninitialized address variable).

    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function tryRecover(bytes32 hash, bytes memory signature)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            for {} 1 {} {
                mstore(0x00, hash)
                mstore(0x40, mload(add(signature, 0x20))) // `r`.
                if eq(mload(signature), 64) {
                    let vs := mload(add(signature, 0x40))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(mload(signature), 65) {
                    mstore(0x20, byte(0, mload(add(signature, 0x60)))) // `v`.
                    mstore(0x60, mload(add(signature, 0x40))) // `s`.
                    break
                }
                result := 0
                break
            }
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    result, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function tryRecoverCalldata(bytes32 hash, bytes calldata signature)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            for {} 1 {} {
                if eq(signature.length, 64) {
                    let vs := calldataload(add(signature.offset, 0x20))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x40, calldataload(signature.offset)) // `r`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(signature.length, 65) {
                    mstore(0x20, byte(0, calldataload(add(signature.offset, 0x40)))) // `v`.
                    calldatacopy(0x40, signature.offset, 0x40) // Copy `r` and `s`.
                    break
                }
                result := 0
                break
            }
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    result, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the EIP-2098 short form signature defined by `r` and `vs`.
    function tryRecover(bytes32 hash, bytes32 r, bytes32 vs)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, add(shr(255, vs), 27)) // `v`.
            mstore(0x40, r)
            mstore(0x60, shr(1, shl(1, vs))) // `s`.
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    1, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the signature defined by `v`, `r`, `s`.
    function tryRecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, and(v, 0xff))
            mstore(0x40, r)
            mstore(0x60, s)
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    1, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     HASHING OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns an Ethereum Signed Message, created from a `hash`.
    /// This produces a hash corresponding to the one signed with the
    /// [`eth_sign`](https://eth.wiki/json-rpc/API#eth_sign)
    /// JSON-RPC method as part of EIP-191.
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, hash) // Store into scratch space for keccak256.
            mstore(0x00, "\x00\x00\x00\x00\x19Ethereum Signed Message:\n32") // 28 bytes.
            result := keccak256(0x04, 0x3c) // `32 * 2 - (32 - 28) = 60 = 0x3c`.
        }
    }

    /// @dev Returns an Ethereum Signed Message, created from `s`.
    /// This produces a hash corresponding to the one signed with the
    /// [`eth_sign`](https://eth.wiki/json-rpc/API#eth_sign)
    /// JSON-RPC method as part of EIP-191.
    /// Note: Supports lengths of `s` up to 999999 bytes.
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            let sLength := mload(s)
            let o := 0x20
            mstore(o, "\x19Ethereum Signed Message:\n") // 26 bytes, zero-right-padded.
            mstore(0x00, 0x00)
            // Convert the `s.length` to ASCII decimal representation: `base10(s.length)`.
            for { let temp := sLength } 1 {} {
                o := sub(o, 1)
                mstore8(o, add(48, mod(temp, 10)))
                temp := div(temp, 10)
                if iszero(temp) { break }
            }
            let n := sub(0x3a, o) // Header length: `26 + 32 - o`.
            // Throw an out-of-offset error (consumes all gas) if the header exceeds 32 bytes.
            returndatacopy(returndatasize(), returndatasize(), gt(n, 0x20))
            mstore(s, or(mload(0x00), mload(n))) // Temporarily store the header.
            result := keccak256(add(s, sub(0x20, n)), add(n, sLength))
            mstore(s, sLength) // Restore the length.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   EMPTY CALLDATA HELPERS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns an empty calldata bytes.
    function emptySignature() internal pure returns (bytes calldata signature) {
        /// @solidity memory-safe-assembly
        assembly {
            signature.length := 0
        }
    }
}

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