// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}

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

pragma solidity ^0.8.0;

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

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

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;

import "../Strings.sol";

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

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

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

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

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

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

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

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

        return (signer, RecoverError.NoError);
    }

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

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

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/EIP712.sol)

pragma solidity ^0.8.8;

import "./ECDSA.sol";
import "../ShortStrings.sol";
import "../../interfaces/IERC5267.sol";

/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * NOTE: In the upgradeable version of this contract, the cached values will correspond to the address, and the domain
 * separator of the implementation contract. This will cause the `_domainSeparatorV4` function to always rebuild the
 * separator from the immutable values, which is cheaper than accessing a cached version in cold storage.
 *
 * _Available since v3.4._
 *
 * @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
 */
abstract contract EIP712 is IERC5267 {
    using ShortStrings for *;

    bytes32 private constant _TYPE_HASH =
        keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");

    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _cachedDomainSeparator;
    uint256 private immutable _cachedChainId;
    address private immutable _cachedThis;

    bytes32 private immutable _hashedName;
    bytes32 private immutable _hashedVersion;

    ShortString private immutable _name;
    ShortString private immutable _version;
    string private _nameFallback;
    string private _versionFallback;

    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        _name = name.toShortStringWithFallback(_nameFallback);
        _version = version.toShortStringWithFallback(_versionFallback);
        _hashedName = keccak256(bytes(name));
        _hashedVersion = keccak256(bytes(version));

        _cachedChainId = block.chainid;
        _cachedDomainSeparator = _buildDomainSeparator();
        _cachedThis = address(this);
    }

    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (address(this) == _cachedThis && block.chainid == _cachedChainId) {
            return _cachedDomainSeparator;
        } else {
            return _buildDomainSeparator();
        }
    }

    function _buildDomainSeparator() private view returns (bytes32) {
        return keccak256(abi.encode(_TYPE_HASH, _hashedName, _hashedVersion, block.chainid, address(this)));
    }

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

    /**
     * @dev See {EIP-5267}.
     *
     * _Available since v4.9._
     */
    function eip712Domain()
        public
        view
        virtual
        override
        returns (
            bytes1 fields,
            string memory name,
            string memory version,
            uint256 chainId,
            address verifyingContract,
            bytes32 salt,
            uint256[] memory extensions
        )
    {
        return (
            hex"0f", // 01111
            _name.toStringWithFallback(_nameFallback),
            _version.toStringWithFallback(_versionFallback),
            block.chainid,
            address(this),
            bytes32(0),
            new uint256[](0)
        );
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * The default value of {decimals} is 18. To change this, you should override
 * this function so it returns a different value.
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

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

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

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

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

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

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

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

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

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

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

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

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

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

        return true;
    }

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

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
            // decrementing then incrementing.
            _balances[to] += amount;
        }

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

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

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

        _totalSupply += amount;
        unchecked {
            // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
            _balances[account] += amount;
        }
        emit Transfer(address(0), account, amount);

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

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

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

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            // Overflow not possible: amount <= accountBalance <= totalSupply.
            _totalSupply -= amount;
        }

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

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

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

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

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

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/ERC20Permit.sol)

pragma solidity ^0.8.0;

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

/**
 * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * _Available since v3.4._
 */
abstract contract ERC20Permit is ERC20, IERC20Permit, EIP712 {
    using Counters for Counters.Counter;

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

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private constant _PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    /**
     * @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.
     * However, to ensure consistency with the upgradeable transpiler, we will continue
     * to reserve a slot.
     * @custom:oz-renamed-from _PERMIT_TYPEHASH
     */
    // solhint-disable-next-line var-name-mixedcase
    bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;

    /**
     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
     *
     * It's a good idea to use the same `name` that is defined as the ERC20 token name.
     */
    constructor(string memory name) EIP712(name, "1") {}

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

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

        bytes32 hash = _hashTypedDataV4(structHash);

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

        _approve(owner, spender, value);
    }

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

    /**
     * @inheritdoc IERC20Permit
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view override returns (bytes32) {
        return _domainSeparatorV4();
    }

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 amount) external returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     *
     * CAUTION: See Security Considerations above.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC5267.sol)

pragma solidity ^0.8.0;

interface IERC5267 {
    /**
     * @dev MAY be emitted to signal that the domain could have changed.
     */
    event EIP712DomainChanged();

    /**
     * @dev returns the fields and values that describe the domain separator used by this contract for EIP-712
     * signature.
     */
    function eip712Domain()
        external
        view
        returns (
            bytes1 fields,
            string memory name,
            string memory version,
            uint256 chainId,
            address verifyingContract,
            bytes32 salt,
            uint256[] memory extensions
        );
}

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

pragma solidity >=0.6.2;

import './IUniswapV2Router01.sol';

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                // The surrounding unchecked block does not change this fact.
                // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1, "Math: mulDiv overflow");

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10 ** 64) {
                value /= 10 ** 64;
                result += 64;
            }
            if (value >= 10 ** 32) {
                value /= 10 ** 32;
                result += 32;
            }
            if (value >= 10 ** 16) {
                value /= 10 ** 16;
                result += 16;
            }
            if (value >= 10 ** 8) {
                value /= 10 ** 8;
                result += 8;
            }
            if (value >= 10 ** 4) {
                value /= 10 ** 4;
                result += 4;
            }
            if (value >= 10 ** 2) {
                value /= 10 ** 2;
                result += 2;
            }
            if (value >= 10 ** 1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity 0.8.23;

import {ERC20Permit} from "@openzeppelin/contracts/token/ERC20/extensions/ERC20Permit.sol";
import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import {Ownable} from "solady/src/auth/Ownable.sol";
import {SafeTransferLib} from "solady/src/utils/SafeTransferLib.sol";
import {IUniswapV2Router02} from "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
import {IUniswapV2Factory} from "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import {Proxyable} from "./utils/Proxyable.sol";

contract NitroDome is Ownable, ERC20Permit, Proxyable {
    IUniswapV2Router02 public uniswapV2Router;

    bool public burnDisabled; // flag to disable burn
    bool public initialized; // flag to prevent reinitialization
    bool public mintDisabled; // flag to disable mint
    bool private _inSwap; // flag to prevent reentrancy

    address public taxRecipient; // address to receive accrued tax tokens
    address public treasury; // address to receive ETH from contract
    address public uniswapV2Pair; // address of Uniswap V2 pair

    uint256 public buyTax = 200; // 2.00%
    uint256 public maxAmountToLiquify = 10000 ether; // 10000 tokens
    uint256 public minAmountToLiquify = 500 ether; // 500 tokens
    uint256 public sellTax = 200; // 2.00%
    uint256 private _supply = 100000000 ether; // 100M tokens

    mapping(address => bool) public isExcludedFromFee;

    error AmountCannotBeZero();
    error BurnDisabled();
    error ExceedsMaxSupply();
    error FailedETHSend();
    error MaxTaxExceeded();
    error MintDisabled();
    error PairIsAlreadySet();
    error ZeroAddress();

    event ExcludeFromFee(
        address indexed owner,
        address indexed account,
        bool indexed isExcluded
    );
    event Initialize(
        address indexed owner,
        address indexed uniswapV2Router,
        address indexed treasury,
        bool isWrapper,
        address taxRecipient
    );
    event SetTaxRecipient(address indexed owner, address indexed taxRecipient);
    event SetTreasury(address indexed owner, address indexed treasury);
    event UpdateUniswapV2Pair(address indexed owner, address indexed pair);

    modifier lockTheSwap() {
        _inSwap = true;
        _;
        _inSwap = false;
    }

    modifier NotZeroAddress(address value) {
        if (value == address(0)) revert ZeroAddress();
        _;
    }

    /**
     * @dev Constructor
     * @param name_ Token name
     * @param symbol_ Token symbol
     * @param _owner Owner address
     */
    constructor(
        string memory name_,
        string memory symbol_,
        address _owner
    ) NotZeroAddress(_owner) ERC20(name_, symbol_) ERC20Permit(name_) {
        _initializeOwner(_owner);
    }

    /**
     * @dev Initialize
     * @param _uniswapV2Router Uniswap V2 Router address
     * @param _treasury Treasury address
     * @param isWrapper Flag to determine if contract is a wrapper
     * @param _taxRecipient Tax recipient address
     */
    function initialize(
        address _uniswapV2Router,
        address _treasury,
        bool isWrapper,
        address _taxRecipient
    )
        external
        NotZeroAddress(_uniswapV2Router)
        NotZeroAddress(_treasury)
        onlyOwner
    {
        if (initialized) revert AlreadyInitialized();
        initialized = true;

        uniswapV2Router = IUniswapV2Router02(_uniswapV2Router);
        treasury = _treasury;

        //create pair
        address _uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory())
            .createPair(address(this), uniswapV2Router.WETH());
        uniswapV2Pair = _uniswapV2Pair;

        isExcludedFromFee[_uniswapV2Router] = true;
        isExcludedFromFee[address(0xdead)] = true;
        isExcludedFromFee[msg.sender] = true;
        isExcludedFromFee[_treasury] = true;
        isExcludedFromFee[_uniswapV2Pair] = true;

        if (!isWrapper) {
            burnDisabled = true;
            mintDisabled = true;
            taxRecipient = address(this);
            _mint(msg.sender, _supply);
        } else {
            taxRecipient = _taxRecipient;
            isExcludedFromFee[_taxRecipient] = true;
        }
        emit Initialize(
            msg.sender,
            _uniswapV2Router,
            _treasury,
            isWrapper,
            _taxRecipient
        );
    }

    receive() external payable {}

    /**
     * @dev Burn tokens from address
     * @param account Address to burn tokens from
     * @param amount Amount of tokens to burn
     */
    function burnFrom(address account, uint256 amount) external onlyProxy {
        if (burnDisabled) revert BurnDisabled();
        _burn(account, amount);
    }

    /**
     * @dev Disable burn
     */
    function disableBurn() external onlyOwner {
        burnDisabled = true;
    }

    /**
     * @dev Disable mint
     */
    function disableMint() external onlyOwner {
        mintDisabled = true;
    }

    /**
     * @dev Exclude address from fee
     * @param _address Address to exclude from fee
     * @param _status Status of exclusion
     */
    function excludeFromFee(
        address _address,
        bool _status
    ) external onlyOwner NotZeroAddress(_address) {
        isExcludedFromFee[_address] = _status;
        emit ExcludeFromFee(msg.sender, _address, _status);
    }

    /**
     * @dev Mint tokens
     * @param account Address to mint tokens to
     * @param amount Amount of tokens to mint
     */
    function mint(address account, uint256 amount) external onlyProxy {
        if (mintDisabled) revert MintDisabled();
        if (totalSupply() + amount > _supply) revert ExceedsMaxSupply();
        _mint(account, amount);
    }

    /**
     * @dev Set tax for buy transactions
     * @param amount Amount to set as buy tax; 200 = 2%
     */
    function setBuyTax(uint256 amount) public onlyOwner {
        if (amount > 1000) revert MaxTaxExceeded();
        buyTax = amount;
    }

    /**
     * @dev Set max amount to liquify when selling accrued tax tokens
     * @param amount Amount to set as max amount to liquify
     */
    function setMaxAmountToLiquify(uint256 amount) external onlyOwner {
        maxAmountToLiquify = amount;
    }

    /**
     * @dev Set min amount to liquify when selling accrued tax tokens
     * @param amount Amount to set as min amount to liquify
     */
    function setMinAmountToLiquify(uint256 amount) external onlyOwner {
        amount = amount > maxAmountToLiquify ? maxAmountToLiquify : amount;
        minAmountToLiquify = amount;
    }

    /**
     * @dev Set tax for sell transactions
     * @param amount Amount to set as sell tax; 200 = 2%
     */
    function setSellTax(uint256 amount) public onlyOwner {
        if (amount > 1000) revert MaxTaxExceeded();
        sellTax = amount;
    }

    function setTaxRecipeint(address _taxRecipient) external onlyOwner {
        taxRecipient = _taxRecipient;
        isExcludedFromFee[_taxRecipient] = true;
        emit SetTaxRecipient(msg.sender, _taxRecipient);
    }

    /**
     * @dev Set treasury address
     * @param value Address to set as treasury
     */
    function setTreasury(
        address value
    ) external onlyOwner NotZeroAddress(value) {
        treasury = value;
        emit SetTreasury(msg.sender, value);
    }

    /**
     * @dev Set Uniswap V2 pair address
     * @param pair Address to set as Uniswap V2 pair
     */
    function updateUniswapV2Pair(address pair) external onlyOwner {
        _updateUniswapV2Pair(pair);
    }

    /**
     * @dev Withdraw ETH from contract
     */
    function withdrawETH() external onlyOwner {
        SafeTransferLib.safeTransferAllETH(treasury);
    }

    /**
     * @dev Withdraw tokens from contract
     * @param token Address of token to withdraw
     */
    function withdrawTokens(
        address token
    ) external onlyOwner NotZeroAddress(token) {
        SafeTransferLib.safeTransferAll(token, treasury);
    }

    /**
     * @dev Swap tokens for ETH
     * @param tokenAmount Amount of tokens to swap
     */
    function _swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
        IUniswapV2Router02 router = uniswapV2Router;
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = router.WETH();

        _approve(address(this), address(router), tokenAmount);

        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            treasury,
            block.timestamp
        );
    }

    /**
     * @dev Transfer tokens
     * @param from Address to transfer tokens from
     * @param to Address to transfer tokens to
     * @param amount Amount of tokens to transfer
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual override NotZeroAddress(to) NotZeroAddress(from) {
        if (amount == 0) revert AmountCannotBeZero();
        // sender has sufficient balance is checked in base class

        if (from == uniswapV2Pair && !isExcludedFromFee[to] && buyTax > 0) {
            // buy
            uint256 tax;
            unchecked {
                tax = (amount * buyTax) / 1e4;
                amount -= tax;
            }
            super._transfer(from, taxRecipient, tax);
        } else if (
            to == uniswapV2Pair && !isExcludedFromFee[from] && sellTax > 0
        ) {
            // sell
            uint256 tax;
            unchecked {
                tax = (amount * sellTax) / 1e4;
                amount -= tax;
            }
            address _taxRecipient = taxRecipient;
            super._transfer(from, _taxRecipient, tax);

            if (_taxRecipient == address(this)) {
                // taxes on sells only
                uint256 tokensForSwap = balanceOf(address(this));
                if (tokensForSwap >= minAmountToLiquify && !_inSwap) {
                    uint256 _maxAmountToLiquify = maxAmountToLiquify;
                    tokensForSwap = _maxAmountToLiquify < tokensForSwap
                        ? _maxAmountToLiquify
                        : tokensForSwap;
                    _swapTokensForEth(tokensForSwap);
                }
            }
        }
        super._transfer(from, to, amount);
    }

    /**
     * @dev Update Uniswap V2 pair address
     * @param pair Address to set as Uniswap V2 pair
     */
    function _updateUniswapV2Pair(address pair) private {
        address oldPair = uniswapV2Pair;
        isExcludedFromFee[oldPair] = false;
        if (oldPair == pair) revert PairIsAlreadySet();
        uniswapV2Pair = pair;
        isExcludedFromFee[pair] = true;
        emit UpdateUniswapV2Pair(msg.sender, pair);
    }
}

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

/// @notice Simple single owner authorization mixin.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/auth/Ownable.sol)
///
/// @dev Note:
/// This implementation does NOT auto-initialize the owner to `msg.sender`.
/// You MUST call the `_initializeOwner` in the constructor / initializer.
///
/// While the ownable portion follows
/// [EIP-173](https://eips.ethereum.org/EIPS/eip-173) for compatibility,
/// the nomenclature for the 2-step ownership handover may be unique to this codebase.
abstract contract Ownable {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The caller is not authorized to call the function.
    error Unauthorized();

    /// @dev The `newOwner` cannot be the zero address.
    error NewOwnerIsZeroAddress();

    /// @dev The `pendingOwner` does not have a valid handover request.
    error NoHandoverRequest();

    /// @dev Cannot double-initialize.
    error AlreadyInitialized();

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

    /// @dev The ownership is transferred from `oldOwner` to `newOwner`.
    /// This event is intentionally kept the same as OpenZeppelin's Ownable to be
    /// compatible with indexers and [EIP-173](https://eips.ethereum.org/EIPS/eip-173),
    /// despite it not being as lightweight as a single argument event.
    event OwnershipTransferred(address indexed oldOwner, address indexed newOwner);

    /// @dev An ownership handover to `pendingOwner` has been requested.
    event OwnershipHandoverRequested(address indexed pendingOwner);

    /// @dev The ownership handover to `pendingOwner` has been canceled.
    event OwnershipHandoverCanceled(address indexed pendingOwner);

    /// @dev `keccak256(bytes("OwnershipTransferred(address,address)"))`.
    uint256 private constant _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE =
        0x8be0079c531659141344cd1fd0a4f28419497f9722a3daafe3b4186f6b6457e0;

    /// @dev `keccak256(bytes("OwnershipHandoverRequested(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE =
        0xdbf36a107da19e49527a7176a1babf963b4b0ff8cde35ee35d6cd8f1f9ac7e1d;

    /// @dev `keccak256(bytes("OwnershipHandoverCanceled(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE =
        0xfa7b8eab7da67f412cc9575ed43464468f9bfbae89d1675917346ca6d8fe3c92;

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

    /// @dev The owner slot is given by:
    /// `bytes32(~uint256(uint32(bytes4(keccak256("_OWNER_SLOT_NOT")))))`.
    /// It is intentionally chosen to be a high value
    /// to avoid collision with lower slots.
    /// The choice of manual storage layout is to enable compatibility
    /// with both regular and upgradeable contracts.
    bytes32 internal constant _OWNER_SLOT =
        0xffffffffffffffffffffffffffffffffffffffffffffffffffffffff74873927;

    /// The ownership handover slot of `newOwner` is given by:
    /// ```
    ///     mstore(0x00, or(shl(96, user), _HANDOVER_SLOT_SEED))
    ///     let handoverSlot := keccak256(0x00, 0x20)
    /// ```
    /// It stores the expiry timestamp of the two-step ownership handover.
    uint256 private constant _HANDOVER_SLOT_SEED = 0x389a75e1;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     INTERNAL FUNCTIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Override to return true to make `_initializeOwner` prevent double-initialization.
    function _guardInitializeOwner() internal pure virtual returns (bool guard) {}

    /// @dev Initializes the owner directly without authorization guard.
    /// This function must be called upon initialization,
    /// regardless of whether the contract is upgradeable or not.
    /// This is to enable generalization to both regular and upgradeable contracts,
    /// and to save gas in case the initial owner is not the caller.
    /// For performance reasons, this function will not check if there
    /// is an existing owner.
    function _initializeOwner(address newOwner) internal virtual {
        if (_guardInitializeOwner()) {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                if sload(ownerSlot) {
                    mstore(0x00, 0x0dc149f0) // `AlreadyInitialized()`.
                    revert(0x1c, 0x04)
                }
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Store the new value.
                sstore(ownerSlot, or(newOwner, shl(255, iszero(newOwner))))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
            }
        } else {
            /// @solidity memory-safe-assembly
            assembly {
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Store the new value.
                sstore(_OWNER_SLOT, newOwner)
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
            }
        }
    }

    /// @dev Sets the owner directly without authorization guard.
    function _setOwner(address newOwner) internal virtual {
        if (_guardInitializeOwner()) {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
                // Store the new value.
                sstore(ownerSlot, or(newOwner, shl(255, iszero(newOwner))))
            }
        } else {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
                // Store the new value.
                sstore(ownerSlot, newOwner)
            }
        }
    }

    /// @dev Throws if the sender is not the owner.
    function _checkOwner() internal view virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // If the caller is not the stored owner, revert.
            if iszero(eq(caller(), sload(_OWNER_SLOT))) {
                mstore(0x00, 0x82b42900) // `Unauthorized()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /// @dev Returns how long a two-step ownership handover is valid for in seconds.
    /// Override to return a different value if needed.
    /// Made internal to conserve bytecode. Wrap it in a public function if needed.
    function _ownershipHandoverValidFor() internal view virtual returns (uint64) {
        return 48 * 3600;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  PUBLIC UPDATE FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Allows the owner to transfer the ownership to `newOwner`.
    function transferOwnership(address newOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(shl(96, newOwner)) {
                mstore(0x00, 0x7448fbae) // `NewOwnerIsZeroAddress()`.
                revert(0x1c, 0x04)
            }
        }
        _setOwner(newOwner);
    }

    /// @dev Allows the owner to renounce their ownership.
    function renounceOwnership() public payable virtual onlyOwner {
        _setOwner(address(0));
    }

    /// @dev Request a two-step ownership handover to the caller.
    /// The request will automatically expire in 48 hours (172800 seconds) by default.
    function requestOwnershipHandover() public payable virtual {
        unchecked {
            uint256 expires = block.timestamp + _ownershipHandoverValidFor();
            /// @solidity memory-safe-assembly
            assembly {
                // Compute and set the handover slot to `expires`.
                mstore(0x0c, _HANDOVER_SLOT_SEED)
                mstore(0x00, caller())
                sstore(keccak256(0x0c, 0x20), expires)
                // Emit the {OwnershipHandoverRequested} event.
                log2(0, 0, _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE, caller())
            }
        }
    }

    /// @dev Cancels the two-step ownership handover to the caller, if any.
    function cancelOwnershipHandover() public payable virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x20), 0)
            // Emit the {OwnershipHandoverCanceled} event.
            log2(0, 0, _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE, caller())
        }
    }

    /// @dev Allows the owner to complete the two-step ownership handover to `pendingOwner`.
    /// Reverts if there is no existing ownership handover requested by `pendingOwner`.
    function completeOwnershipHandover(address pendingOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            let handoverSlot := keccak256(0x0c, 0x20)
            // If the handover does not exist, or has expired.
            if gt(timestamp(), sload(handoverSlot)) {
                mstore(0x00, 0x6f5e8818) // `NoHandoverRequest()`.
                revert(0x1c, 0x04)
            }
            // Set the handover slot to 0.
            sstore(handoverSlot, 0)
        }
        _setOwner(pendingOwner);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   PUBLIC READ FUNCTIONS                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the owner of the contract.
    function owner() public view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := sload(_OWNER_SLOT)
        }
    }

    /// @dev Returns the expiry timestamp for the two-step ownership handover to `pendingOwner`.
    function ownershipHandoverExpiresAt(address pendingOwner)
        public
        view
        virtual
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the handover slot.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            // Load the handover slot.
            result := sload(keccak256(0x0c, 0x20))
        }
    }

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

    /// @dev Marks a function as only callable by the owner.
    modifier onlyOwner() virtual {
        _checkOwner();
        _;
    }
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.23;

import {Ownable} from "solady/src/auth/Ownable.sol";

abstract contract Proxyable is Ownable {

    mapping(address => bool) public proxyToApproved; // proxy allowance for interaction with future contract

    error OnlyProxyAllowed();
    
    modifier onlyProxy() {
        if (!proxyToApproved[msg.sender]) revert OnlyProxyAllowed();
        _;
    }

    function setProxyState(address proxyAddress, bool value) public onlyOwner {
        proxyToApproved[proxyAddress] = value;
    } 
}

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

/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/SafeTransferLib.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @author Permit2 operations from (https://github.com/Uniswap/permit2/blob/main/src/libraries/Permit2Lib.sol)
///
/// @dev Note:
/// - For ETH transfers, please use `forceSafeTransferETH` for DoS protection.
/// - For ERC20s, this implementation won't check that a token has code,
///   responsibility is delegated to the caller.
library SafeTransferLib {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The ETH transfer has failed.
    error ETHTransferFailed();

    /// @dev The ERC20 `transferFrom` has failed.
    error TransferFromFailed();

    /// @dev The ERC20 `transfer` has failed.
    error TransferFailed();

    /// @dev The ERC20 `approve` has failed.
    error ApproveFailed();

    /// @dev The Permit2 operation has failed.
    error Permit2Failed();

    /// @dev The Permit2 amount must be less than `2**160 - 1`.
    error Permit2AmountOverflow();

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

    /// @dev Suggested gas stipend for contract receiving ETH that disallows any storage writes.
    uint256 internal constant GAS_STIPEND_NO_STORAGE_WRITES = 2300;

    /// @dev Suggested gas stipend for contract receiving ETH to perform a few
    /// storage reads and writes, but low enough to prevent griefing.
    uint256 internal constant GAS_STIPEND_NO_GRIEF = 100000;

    /// @dev The unique EIP-712 domain domain separator for the DAI token contract.
    bytes32 internal constant DAI_DOMAIN_SEPARATOR =
        0xdbb8cf42e1ecb028be3f3dbc922e1d878b963f411dc388ced501601c60f7c6f7;

    /// @dev The address for the WETH9 contract on Ethereum mainnet.
    address internal constant WETH9 = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;

    /// @dev The canonical Permit2 address.
    /// [Github](https://github.com/Uniswap/permit2)
    /// [Etherscan](https://etherscan.io/address/0x000000000022D473030F116dDEE9F6B43aC78BA3)
    address internal constant PERMIT2 = 0x000000000022D473030F116dDEE9F6B43aC78BA3;

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

    // If the ETH transfer MUST succeed with a reasonable gas budget, use the force variants.
    //
    // The regular variants:
    // - Forwards all remaining gas to the target.
    // - Reverts if the target reverts.
    // - Reverts if the current contract has insufficient balance.
    //
    // The force variants:
    // - Forwards with an optional gas stipend
    //   (defaults to `GAS_STIPEND_NO_GRIEF`, which is sufficient for most cases).
    // - If the target reverts, or if the gas stipend is exhausted,
    //   creates a temporary contract to force send the ETH via `SELFDESTRUCT`.
    //   Future compatible with `SENDALL`: https://eips.ethereum.org/EIPS/eip-4758.
    // - Reverts if the current contract has insufficient balance.
    //
    // The try variants:
    // - Forwards with a mandatory gas stipend.
    // - Instead of reverting, returns whether the transfer succeeded.

    /// @dev Sends `amount` (in wei) ETH to `to`.
    function safeTransferETH(address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(call(gas(), to, amount, codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /// @dev Sends all the ETH in the current contract to `to`.
    function safeTransferAllETH(address to) internal {
        /// @solidity memory-safe-assembly
        assembly {
            // Transfer all the ETH and check if it succeeded or not.
            if iszero(call(gas(), to, selfbalance(), codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /// @dev Force sends `amount` (in wei) ETH to `to`, with a `gasStipend`.
    function forceSafeTransferETH(address to, uint256 amount, uint256 gasStipend) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if lt(selfbalance(), amount) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
            if iszero(call(gasStipend, to, amount, codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(amount, 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }

    /// @dev Force sends all the ETH in the current contract to `to`, with a `gasStipend`.
    function forceSafeTransferAllETH(address to, uint256 gasStipend) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(call(gasStipend, to, selfbalance(), codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(selfbalance(), 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }

    /// @dev Force sends `amount` (in wei) ETH to `to`, with `GAS_STIPEND_NO_GRIEF`.
    function forceSafeTransferETH(address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if lt(selfbalance(), amount) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
            if iszero(call(GAS_STIPEND_NO_GRIEF, to, amount, codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(amount, 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }

    /// @dev Force sends all the ETH in the current contract to `to`, with `GAS_STIPEND_NO_GRIEF`.
    function forceSafeTransferAllETH(address to) internal {
        /// @solidity memory-safe-assembly
        assembly {
            // forgefmt: disable-next-item
            if iszero(call(GAS_STIPEND_NO_GRIEF, to, selfbalance(), codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(selfbalance(), 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }

    /// @dev Sends `amount` (in wei) ETH to `to`, with a `gasStipend`.
    function trySafeTransferETH(address to, uint256 amount, uint256 gasStipend)
        internal
        returns (bool success)
    {
        /// @solidity memory-safe-assembly
        assembly {
            success := call(gasStipend, to, amount, codesize(), 0x00, codesize(), 0x00)
        }
    }

    /// @dev Sends all the ETH in the current contract to `to`, with a `gasStipend`.
    function trySafeTransferAllETH(address to, uint256 gasStipend)
        internal
        returns (bool success)
    {
        /// @solidity memory-safe-assembly
        assembly {
            success := call(gasStipend, to, selfbalance(), codesize(), 0x00, codesize(), 0x00)
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      ERC20 OPERATIONS                      */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Sends `amount` of ERC20 `token` from `from` to `to`.
    /// Reverts upon failure.
    ///
    /// The `from` account must have at least `amount` approved for
    /// the current contract to manage.
    function safeTransferFrom(address token, address from, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x60, amount) // Store the `amount` argument.
            mstore(0x40, to) // Store the `to` argument.
            mstore(0x2c, shl(96, from)) // Store the `from` argument.
            mstore(0x0c, 0x23b872dd000000000000000000000000) // `transferFrom(address,address,uint256)`.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x1c, 0x64, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x7939f424) // `TransferFromFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot to zero.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Sends `amount` of ERC20 `token` from `from` to `to`.
    ///
    /// The `from` account must have at least `amount` approved for the current contract to manage.
    function trySafeTransferFrom(address token, address from, address to, uint256 amount)
        internal
        returns (bool success)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x60, amount) // Store the `amount` argument.
            mstore(0x40, to) // Store the `to` argument.
            mstore(0x2c, shl(96, from)) // Store the `from` argument.
            mstore(0x0c, 0x23b872dd000000000000000000000000) // `transferFrom(address,address,uint256)`.
            success :=
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x1c, 0x64, 0x00, 0x20)
                )
            mstore(0x60, 0) // Restore the zero slot to zero.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Sends all of ERC20 `token` from `from` to `to`.
    /// Reverts upon failure.
    ///
    /// The `from` account must have their entire balance approved for the current contract to manage.
    function safeTransferAllFrom(address token, address from, address to)
        internal
        returns (uint256 amount)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x40, to) // Store the `to` argument.
            mstore(0x2c, shl(96, from)) // Store the `from` argument.
            mstore(0x0c, 0x70a08231000000000000000000000000) // `balanceOf(address)`.
            // Read the balance, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    gt(returndatasize(), 0x1f), // At least 32 bytes returned.
                    staticcall(gas(), token, 0x1c, 0x24, 0x60, 0x20)
                )
            ) {
                mstore(0x00, 0x7939f424) // `TransferFromFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x00, 0x23b872dd) // `transferFrom(address,address,uint256)`.
            amount := mload(0x60) // The `amount` is already at 0x60. We'll need to return it.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x1c, 0x64, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x7939f424) // `TransferFromFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot to zero.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }

    /// @dev Sends `amount` of ERC20 `token` from the current contract to `to`.
    /// Reverts upon failure.
    function safeTransfer(address token, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, to) // Store the `to` argument.
            mstore(0x34, amount) // Store the `amount` argument.
            mstore(0x00, 0xa9059cbb000000000000000000000000) // `transfer(address,uint256)`.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x90b8ec18) // `TransferFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }

    /// @dev Sends all of ERC20 `token` from the current contract to `to`.
    /// Reverts upon failure.
    function safeTransferAll(address token, address to) internal returns (uint256 amount) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, 0x70a08231) // Store the function selector of `balanceOf(address)`.
            mstore(0x20, address()) // Store the address of the current contract.
            // Read the balance, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    gt(returndatasize(), 0x1f), // At least 32 bytes returned.
                    staticcall(gas(), token, 0x1c, 0x24, 0x34, 0x20)
                )
            ) {
                mstore(0x00, 0x90b8ec18) // `TransferFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x14, to) // Store the `to` argument.
            amount := mload(0x34) // The `amount` is already at 0x34. We'll need to return it.
            mstore(0x00, 0xa9059cbb000000000000000000000000) // `transfer(address,uint256)`.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x90b8ec18) // `TransferFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }

    /// @dev Sets `amount` of ERC20 `token` for `to` to manage on behalf of the current contract.
    /// Reverts upon failure.
    function safeApprove(address token, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, to) // Store the `to` argument.
            mstore(0x34, amount) // Store the `amount` argument.
            mstore(0x00, 0x095ea7b3000000000000000000000000) // `approve(address,uint256)`.
            // Perform the approval, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x3e3f8f73) // `ApproveFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }

    /// @dev Sets `amount` of ERC20 `token` for `to` to manage on behalf of the current contract.
    /// If the initial attempt to approve fails, attempts to reset the approved amount to zero,
    /// then retries the approval again (some tokens, e.g. USDT, requires this).
    /// Reverts upon failure.
    function safeApproveWithRetry(address token, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, to) // Store the `to` argument.
            mstore(0x34, amount) // Store the `amount` argument.
            mstore(0x00, 0x095ea7b3000000000000000000000000) // `approve(address,uint256)`.
            // Perform the approval, retrying upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x34, 0) // Store 0 for the `amount`.
                mstore(0x00, 0x095ea7b3000000000000000000000000) // `approve(address,uint256)`.
                pop(call(gas(), token, 0, 0x10, 0x44, codesize(), 0x00)) // Reset the approval.
                mstore(0x34, amount) // Store back the original `amount`.
                // Retry the approval, reverting upon failure.
                if iszero(
                    and(
                        or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                        call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                    )
                ) {
                    mstore(0x00, 0x3e3f8f73) // `ApproveFailed()`.
                    revert(0x1c, 0x04)
                }
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }

    /// @dev Returns the amount of ERC20 `token` owned by `account`.
    /// Returns zero if the `token` does not exist.
    function balanceOf(address token, address account) internal view returns (uint256 amount) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, account) // Store the `account` argument.
            mstore(0x00, 0x70a08231000000000000000000000000) // `balanceOf(address)`.
            amount :=
                mul( // The arguments of `mul` are evaluated from right to left.
                    mload(0x20),
                    and( // The arguments of `and` are evaluated from right to left.
                        gt(returndatasize(), 0x1f), // At least 32 bytes returned.
                        staticcall(gas(), token, 0x10, 0x24, 0x20, 0x20)
                    )
                )
        }
    }

    /// @dev Sends `amount` of ERC20 `token` from `from` to `to`.
    /// If the initial attempt fails, try to use Permit2 to transfer the token.
    /// Reverts upon failure.
    ///
    /// The `from` account must have at least `amount` approved for the current contract to manage.
    function safeTransferFrom2(address token, address from, address to, uint256 amount) internal {
        if (!trySafeTransferFrom(token, from, to, amount)) {
            permit2TransferFrom(token, from, to, amount);
        }
    }

    /// @dev Sends `amount` of ERC20 `token` from `from` to `to` via Permit2.
    /// Reverts upon failure.
    function permit2TransferFrom(address token, address from, address to, uint256 amount)
        internal
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40)
            mstore(add(m, 0x74), shr(96, shl(96, token)))
            mstore(add(m, 0x54), amount)
            mstore(add(m, 0x34), to)
            mstore(add(m, 0x20), shl(96, from))
            // `transferFrom(address,address,uint160,address)`.
            mstore(m, 0x36c78516000000000000000000000000)
            let p := mul(PERMIT2, iszero(shr(160, amount)))
            if iszero(mul(call(gas(), p, 0, add(m, 0x10), 0x84, codesize(), 0x00), extcodesize(p)))
            {
                mstore(0x00, 0x7939f4248757f0fd) // `TransferFromFailed()` or `Permit2AmountOverflow()`.
                revert(add(0x18, shl(2, iszero(p))), 0x04)
            }
        }
    }

    /// @dev Permit a user to spend a given amount of
    /// another user's tokens via native EIP-2612 permit if possible, falling
    /// back to Permit2 if native permit fails or is not implemented on the token.
    function permit2(
        address token,
        address owner,
        address spender,
        uint256 amount,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        bool success;
        /// @solidity memory-safe-assembly
        assembly {
            for {} shl(96, xor(token, WETH9)) {} {
                mstore(0x00, 0x3644e515) // `DOMAIN_SEPARATOR()`.
                if iszero(
                    and( // The arguments of `and` are evaluated from right to left.
                        lt(iszero(mload(0x00)), eq(returndatasize(), 0x20)), // Returns 1 non-zero word.
                        // Gas stipend to limit gas burn for tokens that don't refund gas when
                        // an non-existing function is called. 5K should be enough for a SLOAD.
                        staticcall(5000, token, 0x1c, 0x04, 0x00, 0x20)
                    )
                ) { break }
                let m := mload(0x40)
                mstore(add(m, 0x34), spender)
                mstore(add(m, 0x20), shl(96, owner))
                mstore(add(m, 0x74), deadline)
                if eq(mload(0x00), DAI_DOMAIN_SEPARATOR) {
                    mstore(0x14, owner)
                    mstore(0x00, 0x7ecebe00000000000000000000000000) // `nonces(address)`.
                    mstore(add(m, 0x94), staticcall(gas(), token, 0x10, 0x24, add(m, 0x54), 0x20))
                    mstore(m, 0x8fcbaf0c000000000000000000000000) // `IDAIPermit.permit`.
                    // `nonces` is already at `add(m, 0x54)`.
                    // `1` is already stored at `add(m, 0x94)`.
                    mstore(add(m, 0xb4), and(0xff, v))
                    mstore(add(m, 0xd4), r)
                    mstore(add(m, 0xf4), s)
                    success := call(gas(), token, 0, add(m, 0x10), 0x104, codesize(), 0x00)
                    break
                }
                mstore(m, 0xd505accf000000000000000000000000) // `IERC20Permit.permit`.
                mstore(add(m, 0x54), amount)
                mstore(add(m, 0x94), and(0xff, v))
                mstore(add(m, 0xb4), r)
                mstore(add(m, 0xd4), s)
                success := call(gas(), token, 0, add(m, 0x10), 0xe4, codesize(), 0x00)
                break
            }
        }
        if (!success) simplePermit2(token, owner, spender, amount, deadline, v, r, s);
    }

    /// @dev Simple permit on the Permit2 contract.
    function simplePermit2(
        address token,
        address owner,
        address spender,
        uint256 amount,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40)
            mstore(m, 0x927da105) // `allowance(address,address,address)`.
            {
                let addressMask := shr(96, not(0))
                mstore(add(m, 0x20), and(addressMask, owner))
                mstore(add(m, 0x40), and(addressMask, token))
                mstore(add(m, 0x60), and(addressMask, spender))
                mstore(add(m, 0xc0), and(addressMask, spender))
            }
            let p := mul(PERMIT2, iszero(shr(160, amount)))
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    gt(returndatasize(), 0x5f), // Returns 3 words: `amount`, `expiration`, `nonce`.
                    staticcall(gas(), p, add(m, 0x1c), 0x64, add(m, 0x60), 0x60)
                )
            ) {
                mstore(0x00, 0x6b836e6b8757f0fd) // `Permit2Failed()` or `Permit2AmountOverflow()`.
                revert(add(0x18, shl(2, iszero(p))), 0x04)
            }
            mstore(m, 0x2b67b570) // `Permit2.permit` (PermitSingle variant).
            // `owner` is already `add(m, 0x20)`.
            // `token` is already at `add(m, 0x40)`.
            mstore(add(m, 0x60), amount)
            mstore(add(m, 0x80), 0xffffffffffff) // `expiration = type(uint48).max`.
            // `nonce` is already at `add(m, 0xa0)`.
            // `spender` is already at `add(m, 0xc0)`.
            mstore(add(m, 0xe0), deadline)
            mstore(add(m, 0x100), 0x100) // `signature` offset.
            mstore(add(m, 0x120), 0x41) // `signature` length.
            mstore(add(m, 0x140), r)
            mstore(add(m, 0x160), s)
            mstore(add(m, 0x180), shl(248, v))
            if iszero(call(gas(), p, 0, add(m, 0x1c), 0x184, codesize(), 0x00)) {
                mstore(0x00, 0x6b836e6b) // `Permit2Failed()`.
                revert(0x1c, 0x04)
            }
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/ShortStrings.sol)

pragma solidity ^0.8.8;

import "./StorageSlot.sol";

// | string  | 0xAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA   |
// | length  | 0x                                                              BB |
type ShortString is bytes32;

/**
 * @dev This library provides functions to convert short memory strings
 * into a `ShortString` type that can be used as an immutable variable.
 *
 * Strings of arbitrary length can be optimized using this library if
 * they are short enough (up to 31 bytes) by packing them with their
 * length (1 byte) in a single EVM word (32 bytes). Additionally, a
 * fallback mechanism can be used for every other case.
 *
 * Usage example:
 *
 * ```solidity
 * contract Named {
 *     using ShortStrings for *;
 *
 *     ShortString private immutable _name;
 *     string private _nameFallback;
 *
 *     constructor(string memory contractName) {
 *         _name = contractName.toShortStringWithFallback(_nameFallback);
 *     }
 *
 *     function name() external view returns (string memory) {
 *         return _name.toStringWithFallback(_nameFallback);
 *     }
 * }
 * ```
 */
library ShortStrings {
    // Used as an identifier for strings longer than 31 bytes.
    bytes32 private constant _FALLBACK_SENTINEL = 0x00000000000000000000000000000000000000000000000000000000000000FF;

    error StringTooLong(string str);
    error InvalidShortString();

    /**
     * @dev Encode a string of at most 31 chars into a `ShortString`.
     *
     * This will trigger a `StringTooLong` error is the input string is too long.
     */
    function toShortString(string memory str) internal pure returns (ShortString) {
        bytes memory bstr = bytes(str);
        if (bstr.length > 31) {
            revert StringTooLong(str);
        }
        return ShortString.wrap(bytes32(uint256(bytes32(bstr)) | bstr.length));
    }

    /**
     * @dev Decode a `ShortString` back to a "normal" string.
     */
    function toString(ShortString sstr) internal pure returns (string memory) {
        uint256 len = byteLength(sstr);
        // using `new string(len)` would work locally but is not memory safe.
        string memory str = new string(32);
        /// @solidity memory-safe-assembly
        assembly {
            mstore(str, len)
            mstore(add(str, 0x20), sstr)
        }
        return str;
    }

    /**
     * @dev Return the length of a `ShortString`.
     */
    function byteLength(ShortString sstr) internal pure returns (uint256) {
        uint256 result = uint256(ShortString.unwrap(sstr)) & 0xFF;
        if (result > 31) {
            revert InvalidShortString();
        }
        return result;
    }

    /**
     * @dev Encode a string into a `ShortString`, or write it to storage if it is too long.
     */
    function toShortStringWithFallback(string memory value, string storage store) internal returns (ShortString) {
        if (bytes(value).length < 32) {
            return toShortString(value);
        } else {
            StorageSlot.getStringSlot(store).value = value;
            return ShortString.wrap(_FALLBACK_SENTINEL);
        }
    }

    /**
     * @dev Decode a string that was encoded to `ShortString` or written to storage using {setWithFallback}.
     */
    function toStringWithFallback(ShortString value, string storage store) internal pure returns (string memory) {
        if (ShortString.unwrap(value) != _FALLBACK_SENTINEL) {
            return toString(value);
        } else {
            return store;
        }
    }

    /**
     * @dev Return the length of a string that was encoded to `ShortString` or written to storage using {setWithFallback}.
     *
     * WARNING: This will return the "byte length" of the string. This may not reflect the actual length in terms of
     * actual characters as the UTF-8 encoding of a single character can span over multiple bytes.
     */
    function byteLengthWithFallback(ShortString value, string storage store) internal view returns (uint256) {
        if (ShortString.unwrap(value) != _FALLBACK_SENTINEL) {
            return byteLength(value);
        } else {
            return bytes(store).length;
        }
    }
}

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

pragma solidity ^0.8.0;

/**
 * @dev Standard signed math utilities missing in the Solidity language.
 */
library SignedMath {
    /**
     * @dev Returns the largest of two signed numbers.
     */
    function max(int256 a, int256 b) internal pure returns (int256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two signed numbers.
     */
    function min(int256 a, int256 b) internal pure returns (int256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two signed numbers without overflow.
     * The result is rounded towards zero.
     */
    function average(int256 a, int256 b) internal pure returns (int256) {
        // Formula from the book "Hacker's Delight"
        int256 x = (a & b) + ((a ^ b) >> 1);
        return x + (int256(uint256(x) >> 255) & (a ^ b));
    }

    /**
     * @dev Returns the absolute unsigned value of a signed value.
     */
    function abs(int256 n) internal pure returns (uint256) {
        unchecked {
            // must be unchecked in order to support `n = type(int256).min`
            return uint256(n >= 0 ? n : -n);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/StorageSlot.sol)
// This file was procedurally generated from scripts/generate/templates/StorageSlot.js.

pragma solidity ^0.8.0;

/**
 * @dev Library for reading and writing primitive types to specific storage slots.
 *
 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
 * This library helps with reading and writing to such slots without the need for inline assembly.
 *
 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
 *
 * Example usage to set ERC1967 implementation slot:
 * ```solidity
 * contract ERC1967 {
 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
 *
 *     function _getImplementation() internal view returns (address) {
 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
 *     }
 *
 *     function _setImplementation(address newImplementation) internal {
 *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
 *     }
 * }
 * ```
 *
 * _Available since v4.1 for `address`, `bool`, `bytes32`, `uint256`._
 * _Available since v4.9 for `string`, `bytes`._
 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }

    struct BooleanSlot {
        bool value;
    }

    struct Bytes32Slot {
        bytes32 value;
    }

    struct Uint256Slot {
        uint256 value;
    }

    struct StringSlot {
        string value;
    }

    struct BytesSlot {
        bytes value;
    }

    /**
     * @dev Returns an `AddressSlot` with member `value` located at `slot`.
     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `StringSlot` with member `value` located at `slot`.
     */
    function getStringSlot(bytes32 slot) internal pure returns (StringSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `StringSlot` representation of the string storage pointer `store`.
     */
    function getStringSlot(string storage store) internal pure returns (StringSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := store.slot
        }
    }

    /**
     * @dev Returns an `BytesSlot` with member `value` located at `slot`.
     */
    function getBytesSlot(bytes32 slot) internal pure returns (BytesSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `BytesSlot` representation of the bytes storage pointer `store`.
     */
    function getBytesSlot(bytes storage store) internal pure returns (BytesSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := store.slot
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Strings.sol)

pragma solidity ^0.8.0;

import "./math/Math.sol";
import "./math/SignedMath.sol";

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `int256` to its ASCII `string` decimal representation.
     */
    function toString(int256 value) internal pure returns (string memory) {
        return string(abi.encodePacked(value < 0 ? "-" : "", toString(SignedMath.abs(value))));
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }

    /**
     * @dev Returns true if the two strings are equal.
     */
    function equal(string memory a, string memory b) internal pure returns (bool) {
        return keccak256(bytes(a)) == keccak256(bytes(b));
    }
}

{
  "compilationTarget": {
    "contracts/TestToken.sol": "TestToken"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "none"
  },
  "optimizer": {
    "enabled": true,
    "runs": 10000000
  },
  "remappings": []
}