// File: @openzeppelin/contracts/interfaces/IERC1271.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC1271.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC1271 standard signature validation method for
 * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
 *
 * _Available since v4.1._
 */
interface IERC1271 {
    /**
     * @dev Should return whether the signature provided is valid for the provided data
     * @param hash      Hash of the data to be signed
     * @param signature Signature byte array associated with _data
     */
    function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
}

// File: @openzeppelin/contracts/proxy/utils/Initializable.sol



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

pragma solidity ^0.8.2;

import "../../utils/Address.sol";

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
 * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
 * case an upgrade adds a module that needs to be initialized.
 *
 * For example:
 *
 * [.hljs-theme-light.nopadding]
 * ```solidity
 * contract MyToken is ERC20Upgradeable {
 *     function initialize() initializer public {
 *         __ERC20_init("MyToken", "MTK");
 *     }
 * }
 *
 * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
 *     function initializeV2() reinitializer(2) public {
 *         __ERC20Permit_init("MyToken");
 *     }
 * }
 * ```
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 *
 * [CAUTION]
 * ====
 * Avoid leaving a contract uninitialized.
 *
 * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
 * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
 * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() {
 *     _disableInitializers();
 * }
 * ```
 * ====
 */
abstract contract Initializable {
    /**
     * @dev Indicates that the contract has been initialized.
     * @custom:oz-retyped-from bool
     */
    uint8 private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Triggered when the contract has been initialized or reinitialized.
     */
    event Initialized(uint8 version);

    /**
     * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
     * `onlyInitializing` functions can be used to initialize parent contracts.
     *
     * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
     * constructor.
     *
     * Emits an {Initialized} event.
     */
    modifier initializer() {
        bool isTopLevelCall = !_initializing;
        require(
            (isTopLevelCall && _initialized < 1) || (!Address.isContract(address(this)) && _initialized == 1),
            "Initializable: contract is already initialized"
        );
        _initialized = 1;
        if (isTopLevelCall) {
            _initializing = true;
        }
        _;
        if (isTopLevelCall) {
            _initializing = false;
            emit Initialized(1);
        }
    }

    /**
     * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
     * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
     * used to initialize parent contracts.
     *
     * A reinitializer may be used after the original initialization step. This is essential to configure modules that
     * are added through upgrades and that require initialization.
     *
     * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
     * cannot be nested. If one is invoked in the context of another, execution will revert.
     *
     * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
     * a contract, executing them in the right order is up to the developer or operator.
     *
     * WARNING: setting the version to 255 will prevent any future reinitialization.
     *
     * Emits an {Initialized} event.
     */
    modifier reinitializer(uint8 version) {
        require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
        _initialized = version;
        _initializing = true;
        _;
        _initializing = false;
        emit Initialized(version);
    }

    /**
     * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
     * {initializer} and {reinitializer} modifiers, directly or indirectly.
     */
    modifier onlyInitializing() {
        require(_initializing, "Initializable: contract is not initializing");
        _;
    }

    /**
     * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
     * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
     * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
     * through proxies.
     *
     * Emits an {Initialized} event the first time it is successfully executed.
     */
    function _disableInitializers() internal virtual {
        require(!_initializing, "Initializable: contract is initializing");
        if (_initialized != type(uint8).max) {
            _initialized = type(uint8).max;
            emit Initialized(type(uint8).max);
        }
    }

    /**
     * @dev Returns the highest version that has been initialized. See {reinitializer}.
     */
    function _getInitializedVersion() internal view returns (uint8) {
        return _initialized;
    }

    /**
     * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
     */
    function _isInitializing() internal view returns (bool) {
        return _initializing;
    }
}

// File: @openzeppelin/contracts/token/ERC20/extensions/IERC20Permit.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

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

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

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// 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);
}

// File: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/IERC20Permit.sol";
import "../../../utils/Address.sol";

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

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

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

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Compatible with tokens that require the approval to be set to
     * 0 before setting it to a non-zero value.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
     * Revert on invalid signature.
     */
    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

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

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

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}

// File: @openzeppelin/contracts/utils/Address.sol



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

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// File: @openzeppelin/contracts/utils/Context.sol



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

pragma solidity ^0.8.0;

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

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

// File: @openzeppelin/contracts/utils/cryptography/ECDSA.sol



// 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));
    }
}

// File: @openzeppelin/contracts/utils/math/Math.sol



// 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);
        }
    }
}

// File: @openzeppelin/contracts/utils/math/SignedMath.sol



// 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);
        }
    }
}

// File: @openzeppelin/contracts/utils/Strings.sol



// 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));
    }
}

// File: contracts/interfaces/external/IWETH.sol



/**
 * SPDX-License-Identifier: UNLICENSED
 */
pragma solidity >=0.8.0;

interface IWETH {
    function deposit() external payable;

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

    function withdraw(uint256) external;
}

// File: contracts/interfaces/IHashflowPool.sol



/**
 * SPDX-License-Identifier: UNLICENSED
 */
pragma solidity >=0.8.0;

import '@openzeppelin/contracts/interfaces/IERC1271.sol';

import './IQuote.sol';

/// @title IHashflowPool
/// @author Victor Ionescu
/**
 * Pool contract used for trading. The Pool can either hold funds or
 * rely on external accounts. External accounts are used in order to preserve
 * Capital Efficiency on the Market Maker side. This way, a Market Maker can
 * make markets using funds that are also used on other venues.
 */
interface IHashflowPool is IQuote, IERC1271 {
    /// @notice Specifies a HashflowPool on a foreign chain.
    struct AuthorizedXChainPool {
        uint16 chainId;
        bytes32 pool;
    }

    /// @notice Contains a signer verification address, and whether trading is enabled.
    struct SignerConfiguration {
        address signer;
        bool enabled;
    }

    /// @notice Emitted when the authorization status of a withdrawal account changes.
    /// @param account The account for which the status changes.
    /// @param authorized The new authorization status.
    event UpdateWithdrawalAccount(address account, bool authorized);

    /// @notice Emitted when the signer key used for the pool has changed.
    /// @param signer The new signer key.
    /// @param prevSigner The old signer key.
    event UpdateSigner(address signer, address prevSigner);

    /// @notice Emitted when liquidity is withdrawn from the pool.
    /// @param token Token being withdrawn.
    /// @param recipient Address receiving the token.
    /// @param withdrawAmount Amount being withdrawn.
    event RemoveLiquidity(
        address token,
        address recipient,
        uint256 withdrawAmount
    );

    /// @notice Emitted when an intra-chain trade happens.
    /// @param trader The trader.
    /// @param effectiveTrader The effective Trader.
    /// @param txid The txid of the quote.
    /// @param baseToken The token the trader sold.
    /// @param quoteToken The token the trader bought.
    /// @param baseTokenAmount The amount of baseToken sold.
    /// @param quoteTokenAmount The amount of quoteToken bought.
    event Trade(
        address trader,
        address effectiveTrader,
        bytes32 txid,
        address baseToken,
        address quoteToken,
        uint256 baseTokenAmount,
        uint256 quoteTokenAmount
    );

    /// @notice Emitted when a cross-chain trade happens.
    /// @param dstChainId The Hashflow Chain ID for the destination chain.
    /// @param dstPool The pool address on the destination chain.
    /// @param trader The trader address.
    /// @param txid The txid of the quote.
    /// @param baseToken The token the trader sold.
    /// @param quoteToken The token the trader bought.
    /// @param baseTokenAmount The amount of baseToken sold.
    /// @param quoteTokenAmount The amount of quoteToken bought.
    event XChainTrade(
        uint16 dstChainId,
        bytes32 dstPool,
        address trader,
        bytes32 dstTrader,
        bytes32 txid,
        address baseToken,
        bytes32 quoteToken,
        uint256 baseTokenAmount,
        uint256 quoteTokenAmount
    );

    /// @notice Emitted when a cross-chain trade is filled.
    /// @param txid The txid identified the quote that was filled.
    event XChainTradeFill(bytes32 txid);

    /// @notice Main initializer.
    /// @param name Name of the pool.
    /// @param signer Signer key used for quote / deposit verification.
    /// @param operations Operations key that governs the pool.
    /// @param router Address of the HashflowRouter contract.
    function initialize(
        string calldata name,
        address signer,
        address operations,
        address router
    ) external;

    /// @notice Returns the pool name.
    function name() external view returns (string memory);

    /// @notice Returns the signer address and whether the pool is enabled.
    function signerConfiguration() external view returns (address, bool);

    /// @notice Returns the Operations address of this pool.
    function operations() external view returns (address);

    /// @notice Returns the Router contract address.
    function router() external view returns (address);

    /// @notice Returns the current nonce for a trader.
    function nonces(address trader) external view returns (uint256);

    /// @notice Removes liquidity from the pool.
    /// @param token Token to withdraw.
    /// @param recipient Address to send token to.
    /// @param amount Amount to withdraw.
    function removeLiquidity(
        address token,
        address recipient,
        uint256 amount
    ) external;

    /// @notice Execute an RFQ-T trade.
    /// @param quote The quote to be executed.
    function tradeRFQT(RFQTQuote memory quote) external payable;

    /// @notice Execute an RFQ-M trade.
    /// @param quote The quote to be executed.
    function tradeRFQM(RFQMQuote memory quote) external;

    /// @notice Execute a cross-chain RFQ-T trade.
    /// @param quote The quote to be executed.
    /// @param trader The account that sends baseToken on this chain.
    function tradeXChainRFQT(XChainRFQTQuote memory quote, address trader)
        external
        payable;

    /// @notice Execute a cross-chain RFQ-M trade.
    /// @param quote The quote to be executed.
    function tradeXChainRFQM(XChainRFQMQuote memory quote) external;

    /// @notice Changes authorization for a set of pools to send X-Chain messages.
    /// @param pools The pools to change authorization status for.
    /// @param authorized The new authorization status.
    function updateXChainPoolAuthorization(
        AuthorizedXChainPool[] calldata pools,
        bool authorized
    ) external;

    /// @notice Changes authorization for an X-Chain Messenger app.
    /// @param xChainMessenger The address of the Messenger app.
    /// @param authorized The new authorization status.
    function updateXChainMessengerAuthorization(
        address xChainMessenger,
        bool authorized
    ) external;

    /// @notice Fills an x-chain order that completed on the source chain.
    /// @param externalAccount The external account to fill from, if any.
    /// @param txid The txid of the quote.
    /// @param trader The trader to receive the funds.
    /// @param quoteToken The token to be sent.
    /// @param quoteTokenAmount The amount of quoteToken to be sent.
    function fillXChain(
        address externalAccount,
        bytes32 txid,
        address trader,
        address quoteToken,
        uint256 quoteTokenAmount
    ) external;

    /// @notice Updates withdrawal account authorization.
    /// @param withdrawalAccounts the accounts for which to update authorization status.
    /// @param authorized The new authorization status.
    function updateWithdrawalAccount(
        address[] memory withdrawalAccounts,
        bool authorized
    ) external;

    /// @notice Updates the signer key.
    /// @param signer The new signer key.
    function updateSigner(address signer) external;

    /// @notice Used by the router to disable pool actions (Trade, Withdraw, Deposit)
    function killswitchOperations(bool enabled) external;

    /// @notice Returns the token reserves for this pool.
    /// @param token The token to check reserves for.
    function getReserves(address token) external view returns (uint256);

    /// @notice Approves a token for spend. Used for 1inch RFQ protocol.
    /// @param token The address of the ERC-20 token.
    /// @param spender The spender address (typically the 1inch RFQ order router)
    /// @param amount The approval amount.
    function approveToken(
        address token,
        address spender,
        uint256 amount
    ) external;

    /// @notice Increases allowance for a token. Used for 1inch RFQ protocol.
    /// @param token The address of the ERC-20 token.
    /// @param spender The spender address (typically the 1inch RFQ order router).
    /// @param amount The approval amount.
    function increaseTokenAllowance(
        address token,
        address spender,
        uint256 amount
    ) external;

    /// @notice Decreases allowance for a token. Used for 1inch RFQ protocol.
    /// @param token The address of the ERC-20 token.
    /// @param spender The spender address (typically the 1inch RFQ order router)
    /// @param amount The approval amount.
    function decreaseTokenAllowance(
        address token,
        address spender,
        uint256 amount
    ) external;
}

// File: contracts/interfaces/IHashflowRouter.sol



/**
 * SPDX-License-Identifier: UNLICENSED
 */
pragma solidity >=0.8.0;

import './IQuote.sol';

/// @title IHashflowRouter
/// @author Victor Ionescu
/**
 * @notice In terms of user-facing functionality, the Router is responsible for:
 * - orchestrating trades
 * - managing cross-chain permissions
 *
 * Every trade requires consent from two parties: the Trader and the Market Maker.
 * However, there are two models to establish consent:
 * - RFQ-T: in this model, the Market Maker provides an EIP-191 signature for the quote,
 *   while the Trader signs the transaction and submits it on-chain
 * - RFQ-M: in this model, the Trader provides an EIP-712 signature for the quote,
 *   the Market Maker provides an EIP-191 signature, and a 3rd party relays the trade.
 *   The 3rd party can be the Market Maker itself.
 *
 * In terms of Hashflow internals, the Router maintains a set of authorized pool
 * contracts that are allowed to be used for trading. This allowlist creates
 * guarantees against malicious behavior, as documented in specific places.
 *
 * The Router contract is not upgradeable. In order to change functionality, a new
 * Router has to be deployed, and new HashflowPool contracts have to be deployed
 * by the Market Makers.
 */
/// @dev Trade / liquidity events are emitted at the HashflowPool level, rather than the router.
interface IHashflowRouter is IQuote {
    /**
     * @notice X-Chain message received from an X-Chain Messenger. This is used by the
     * Router to communicate a fill to a HashflowPool.
     */
    struct XChainFillMessage {
        /// @notice The Hashflow Chain ID of the source chain.
        uint16 srcHashflowChainId;
        /// @notice The address of the HashflowPool on the source chain.
        bytes32 srcPool;
        /// @notice The HashflowPool to disburse funds on the destination chain.
        address dstPool;
        /**
         * @notice The external account linked to the HashflowPool on the destination chain.
         * If the HashflowPool holds funds, this should be bytes32(0).
         */
        address dstExternalAccount;
        /// @notice The recipient of the quoteToken on the destination chain.
        address dstTrader;
        /// @notice The token that the trader buys on the destination chain.
        address quoteToken;
        /// @notice The amount of quoteToken bought.
        uint256 quoteTokenAmount;
        /// @notice Unique identifier for the quote.
        /// @dev Generated off-chain via a distributed UUID generator.
        bytes32 txid;
        /// @notice The caller of the trade function on the source chain.
        bytes32 srcCaller;
        /// @notice The contract to call, if any.
        address dstContract;
        /// @notice The calldata for the contract.
        bytes dstContractCalldata;
    }

    /// @notice Emitted when the authorization status of a pool changes.
    /// @param pool The pool whose status changed.
    /// @param authorized The new auth status.
    event UpdatePoolAuthorizaton(address pool, bool authorized);

    /// @notice Emitted when a sender pool authorization changes.
    /// @param pool Pool address on this chain.
    /// @param otherHashflowChainId Hashflow Chain ID of the other chain.
    /// @param otherChainPool Pool address on the other chain.
    /// @param authorized Whether the pool is authorized.
    event UpdateXChainPoolAuthorization(
        address indexed pool,
        uint16 otherHashflowChainId,
        bytes32 otherChainPool,
        bool authorized
    );

    /// @notice Emitted when the authorization of an x-caller changes.
    /// @param pool Pool address on this chain.
    /// @param otherHashflowChainId Hashflow Chain ID of the other chain.
    /// @param caller Caller address on the other chain.
    /// @param authorized Whether the caller is authorized.
    event UpdateXChainCallerAuthorization(
        address indexed pool,
        uint16 otherHashflowChainId,
        bytes32 caller,
        bool authorized
    );

    /// @notice Emitted when the authorization status of an X-Chain Messenger changes for a pool.
    /// @param pool Pool address for which the Messenger authorization changes.
    /// @param xChainMessenger Address of the Messenger.
    /// @param authorized Whether the X-Chain Messenger is authorized.
    event UpdateXChainMessengerAuthorization(
        address indexed pool,
        address xChainMessenger,
        bool authorized
    );

    /// @notice Emitted when the authorized status of an X-Chain Messenger changes for a callee.
    /// @param callee Address of the callee.
    /// @param xChainMessenger Address of the Messenger.
    /// @param authorized Whether the X-Chain Messenger is authorized.
    event UpdateXChainMessengerCallerAuthorization(
        address indexed callee,
        address xChainMessenger,
        bool authorized
    );

    /// @notice Emitted when the Limit Order Guardian address is updated.
    /// @param guardian The new Guardian address.
    event UpdateLimitOrderGuardian(address guardian);

    /// @notice Initializes the Router. Called one time.
    /// @param factory The address of the HashflowFactory contract.
    function initialize(address factory) external;

    /// @notice Returns the address of the associated HashflowFactor contract.
    function factory() external view returns (address);

    function authorizedXChainPools(
        bytes32 dstPool,
        uint16 srcHChainId,
        bytes32 srcPool
    ) external view returns (bool);

    function authorizedXChainCallers(
        address dstContract,
        uint16 srcHashflowChainId,
        bytes32 caller
    ) external view returns (bool);

    function authorizedXChainMessengersByPool(address pool, address messenger)
        external
        view
        returns (bool);

    function authorizedXChainMessengersByCallee(
        address callee,
        address messenger
    ) external view returns (bool);

    /// @notice Executes an intra-chain RFQ-T trade.
    /// @param quote The quote data to be executed.
    function tradeRFQT(RFQTQuote memory quote) external payable;

    /// @notice Executes an intra-chain RFQ-T trade, leveraging an ERC-20 permit.
    /// @param quote The quote data to be executed.
    /// @dev Does not support native tokens for the baseToken.
    function tradeRFQTWithPermit(
        RFQTQuote memory quote,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s,
        uint256 amountToApprove
    ) external;

    /// @notice Executes an intra-chain RFQ-T trade.
    /// @param quote The quote to be executed.
    function tradeRFQM(RFQMQuote memory quote) external;

    /// @notice Executes an intra-chain RFQ-T trade, leveraging an ERC-20 permit.
    /// @param quote The quote to be executed.
    /// @param deadline The deadline of the ERC-20 permit.
    /// @param v v-part of the signature.
    /// @param r r-part of the signature.
    /// @param s s-part of the signature.
    /// @param amountToApprove The amount being approved.
    function tradeRFQMWithPermit(
        RFQMQuote memory quote,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s,
        uint256 amountToApprove
    ) external;

    /// @notice Executes an intra-chain RFQ-T trade.
    /// @param quote The quote to be executed.
    /// @param guardianSignature A signature issued by the Limit Order Guardian.
    function tradeRFQMLimitOrder(
        RFQMQuote memory quote,
        bytes memory guardianSignature
    ) external;

    /// @notice Executes an intra-chain RFQ-T trade, leveraging an ERC-20 permit.
    /// @param quote The quote to be executed.
    /// @param guardianSignature A signature issued by the Limit Order Guardian.
    /// @param deadline The deadline of the ERC-20 permit.
    /// @param v v-part of the signature.
    /// @param r r-part of the signature.
    /// @param s s-part of the signature.
    /// @param amountToApprove The amount being approved.
    function tradeRFQMLimitOrderWithPermit(
        RFQMQuote memory quote,
        bytes memory guardianSignature,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s,
        uint256 amountToApprove
    ) external;

    /// @notice Executes an RFQ-T cross-chain trade.
    /// @param quote The quote to be executed.
    /// @param dstContract The address of the contract to be called on the destination chain.
    /// @param dstCalldata The calldata for the smart contract call.
    function tradeXChainRFQT(
        XChainRFQTQuote memory quote,
        bytes32 dstContract,
        bytes memory dstCalldata
    ) external payable;

    /// @notice Executes an RFQ-T cross-chain trade, leveraging an ERC-20 permit.
    /// @param quote The quote to be executed.
    /// @param dstContract The address of the contract to be called on the destination chain.
    /// @param dstCalldata The calldata for the smart contract call.
    /// @param deadline The deadline of the ERC-20 permit.
    /// @param v v-part of the signature.
    /// @param r r-part of the signature.
    /// @param s s-part of the signature.
    /// @param amountToApprove The amount being approved.
    function tradeXChainRFQTWithPermit(
        XChainRFQTQuote memory quote,
        bytes32 dstContract,
        bytes memory dstCalldata,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s,
        uint256 amountToApprove
    ) external payable;

    /// @notice Executes an RFQ-M cross-chain trade.
    /// @param quote The quote to be executed.
    /// @param dstContract The address of the contract to be called on the destination chain.
    /// @param dstCalldata The calldata for the smart contract call.
    function tradeXChainRFQM(
        XChainRFQMQuote memory quote,
        bytes32 dstContract,
        bytes memory dstCalldata
    ) external payable;

    /// @notice Similar to tradeXChainRFQm, but includes a spend permit for the baseToken.
    /// @param quote The quote to be executed.
    /// @param dstContract The address of the contract to be called on the destination chain.
    /// @param dstCalldata The calldata for the smart contract call.
    /// @param deadline The deadline of the ERC-20 permit.
    /// @param v v-part of the signature.
    /// @param r r-part of the signature.
    /// @param s s-part of the signature.
    /// @param amountToApprove The amount to approve.
    function tradeXChainRFQMWithPermit(
        XChainRFQMQuote memory quote,
        bytes32 dstContract,
        bytes memory dstCalldata,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s,
        uint256 amountToApprove
    ) external payable;

    /// @notice Completes the second leg of a cross-chain trade.
    /// @param fillMessage Payload containing information necessary to complete the trade.
    function fillXChain(XChainFillMessage memory fillMessage) external;

    /// @notice Returns whether the pool is authorized for trading.
    /// @param pool The address of the HashflowPool.
    function authorizedPools(address pool) external view returns (bool);

    /// @notice Allows the owner to unauthorize a potentially compromised pool. Cannot be reverted.
    /// @param pool The address of the HashflowPool.
    function forceUnauthorizePool(address pool) external;

    /// @notice Authorizes a HashflowPool for trading.
    /// @dev Can only be called by the HashflowFactory or the admin.
    function updatePoolAuthorization(address pool, bool authorized) external;

    /// @notice Updates the authorization status of an X-Chain pool pair.
    /// @param otherHashflowChainId The Hashflow Chain ID of the peer chain.
    /// @param otherPool The 32-byte representation of the Pool address on the peer chain.
    /// @param authorized Whether the pool is authorized to communicate with the sender pool.
    function updateXChainPoolAuthorization(
        uint16 otherHashflowChainId,
        bytes32 otherPool,
        bool authorized
    ) external;

    /// @notice Updates the authorization status of an X-Chain caller.
    /// @param otherHashflowChainId The Hashflow Chain ID of the peer chain.
    /// @param caller The caller address.
    /// @param authorized Whether the caller is authorized to send an x-call to the sender pool.
    function updateXChainCallerAuthorization(
        uint16 otherHashflowChainId,
        bytes32 caller,
        bool authorized
    ) external;

    /// @notice Updates the authorization status of an X-Chain Messenger app.
    /// @param xChainMessenger The address of the Messenger App.
    /// @param authorized The new authorization status.
    function updateXChainMessengerAuthorization(
        address xChainMessenger,
        bool authorized
    ) external;

    /// @notice Updates the authorization status of an X-Chain Messenger app.
    /// @param xChainMessenger The address of the Messenger App.
    /// @param authorized The new authorization status.
    function updateXChainMessengerCallerAuthorization(
        address xChainMessenger,
        bool authorized
    ) external;

    /// @notice Used to stop all operations on a pool, in case of an emergency.
    /// @param pool The address of the HashflowPool.
    /// @param enabled Whether the pool is enabled.
    function killswitchPool(address pool, bool enabled) external;

    /// @notice Used to update the Limit Order Guardian.
    /// @param guardian The address of the new Guardian.
    function updateLimitOrderGuardian(address guardian) external;

    /// @notice Allows the owner to withdraw excess funds from the Router.
    /// @dev Under normal operations, the Router should not have excess funds.
    function withdrawFunds(address token) external;
}

// File: contracts/interfaces/IQuote.sol



/**
 * SPDX-License-Identifier: UNLICENSED
 */
pragma solidity >=0.8.0;

/// @title IQuote
/// @author Victor Ionescu
/**
 * @notice Interface for quote structs used for trading. There are two major types of trades:
 * - intra-chain: atomic transactions within one chain
 * - cross-chain: multi-leg transactions between two chains, which utilize interoperability protocols
 *                such as Wormhole.
 *
 * Separately, there are two trading modes:
 * - RFQ-T: the trader signs the transaction, the market maker signs the quote
 * - RFQ-M: both the trader and Market Maker sign the quote, any relayer can sign the transaction
 */
interface IQuote {
    /// @notice Used for intra-chain RFQ-T trades.
    struct RFQTQuote {
        /// @notice The address of the HashflowPool to trade against.
        address pool;
        /**
         * @notice The external account linked to the HashflowPool.
         * If the HashflowPool holds funds, this should be address(0).
         */
        address externalAccount;
        /// @notice The recipient of the quoteToken at the end of the trade.
        address trader;
        /**
         * @notice The account "effectively" making the trade (ultimately receiving the funds).
         * This is commonly used by aggregators, where a proxy contract (the 'trader')
         * receives the quoteToken, and the effective trader is the user initiating the call.
         *
         * This field DOES NOT influence movement of funds. However, it is used to check against
         * quote replay.
         */
        address effectiveTrader;
        /// @notice The token that the trader sells.
        address baseToken;
        /// @notice The token that the trader buys.
        address quoteToken;
        /**
         * @notice The amount of baseToken sold in this trade. The exchange rate
         * is going to be preserved as the quoteTokenAmount / baseTokenAmount ratio.
         *
         * Most commonly, effectiveBaseTokenAmount will == baseTokenAmount.
         */
        uint256 effectiveBaseTokenAmount;
        /// @notice The max amount of baseToken sold.
        uint256 baseTokenAmount;
        /// @notice The amount of quoteToken bought when baseTokenAmount is sold.
        uint256 quoteTokenAmount;
        /// @notice The Unix timestamp (in seconds) when the quote expires.
        /// @dev This gets checked against block.timestamp.
        uint256 quoteExpiry;
        /// @notice The nonce used by this effectiveTrader. Nonces are used to protect against replay.
        uint256 nonce;
        /// @notice Unique identifier for the quote.
        /// @dev Generated off-chain via a distributed UUID generator.
        bytes32 txid;
        /// @notice Signature provided by the market maker (EIP-191).
        bytes signature;
    }

    /// @notice Used for intra-chain RFQ-M trades.
    struct RFQMQuote {
        /// @notice The address of the HashflowPool to trade against.
        address pool;
        /**
         * @notice The external account linked to the HashflowPool.
         * If the HashflowPool holds funds, this should be address(0).
         */
        address externalAccount;
        /// @notice The account that will be debited baseToken / credited quoteToken.
        address trader;
        /// @notice The token that the trader sells.
        address baseToken;
        /// @notice The token that the trader buys.
        address quoteToken;
        /// @notice The amount of baseToken sold.
        uint256 baseTokenAmount;
        /// @notice The amount of quoteToken bought.
        uint256 quoteTokenAmount;
        /// @notice The Unix timestamp (in seconds) when the quote expires.
        /// @dev This gets checked against block.timestamp.
        uint256 quoteExpiry;
        /// @notice Unique identifier for the quote.
        /// @dev Generated off-chain via a distributed UUID generator.
        bytes32 txid;
        /// @notice Signature provided by the trader (EIP-712).
        bytes takerSignature;
        /// @notice Signature provided by the market maker (EIP-191).
        bytes makerSignature;
    }

    /// @notice Used for cross-chain RFQ-T trades.
    struct XChainRFQTQuote {
        /// @notice The Hashflow Chain ID of the source chain.
        uint16 srcChainId;
        /// @notice The Hashflow Chain ID of the destination chain.
        uint16 dstChainId;
        /// @notice The address of the HashflowPool to trade against on the source chain.
        address srcPool;
        /// @notice The HashflowPool to disburse funds on the destination chain.
        /// @dev This is bytes32 in order to anticipate non-EVM chains.
        bytes32 dstPool;
        /**
         * @notice The external account linked to the HashflowPool on the source chain.
         * If the HashflowPool holds funds, this should be address(0).
         */
        address srcExternalAccount;
        /**
         * @notice The external account linked to the HashflowPool on the destination chain.
         * If the HashflowPool holds funds, this should be bytes32(0).
         */
        bytes32 dstExternalAccount;
        /// @notice The recipient of the quoteToken on the destination chain.
        bytes32 dstTrader;
        /// @notice The token that the trader sells on the source chain.
        address baseToken;
        /// @notice The token that the trader buys on the destination chain.
        bytes32 quoteToken;
        /**
         * @notice The amount of baseToken sold in this trade. The exchange rate
         * is going to be preserved as the quoteTokenAmount / baseTokenAmount ratio.
         *
         * Most commonly, effectiveBaseTokenAmount will == baseTokenAmount.
         */
        uint256 effectiveBaseTokenAmount;
        /// @notice The amount of baseToken sold.
        uint256 baseTokenAmount;
        /// @notice The amount of quoteToken bought.
        uint256 quoteTokenAmount;
        /**
         * @notice The Unix timestamp (in seconds) when the quote expire. Only enforced
         * on the source chain.
         */
        /// @dev This gets checked against block.timestamp.
        uint256 quoteExpiry;
        /// @notice The nonce used by this trader.
        uint256 nonce;
        /// @notice Unique identifier for the quote.
        /// @dev Generated off-chain via a distributed UUID generator.
        bytes32 txid;
        /**
         * @notice The address of the IHashflowXChainMessenger contract used for
         * cross-chain communication.
         */
        address xChainMessenger;
        /// @notice Signature provided by the market maker (EIP-191).
        bytes signature;
    }

    /// @notice Used for Cross-Chain RFQ-M trades.
    struct XChainRFQMQuote {
        /// @notice The Hashflow Chain ID of the source chain.
        uint16 srcChainId;
        /// @notice The Hashflow Chain ID of the destination chain.
        uint16 dstChainId;
        /// @notice The address of the HashflowPool to trade against on the source chain.
        address srcPool;
        /// @notice The HashflowPool to disburse funds on the destination chain.
        /// @dev This is bytes32 in order to anticipate non-EVM chains.
        bytes32 dstPool;
        /**
         * @notice The external account linked to the HashflowPool on the source chain.
         * If the HashflowPool holds funds, this should be address(0).
         */
        address srcExternalAccount;
        /**
         * @notice The external account linked to the HashflowPool on the destination chain.
         * If the HashflowPool holds funds, this should be bytes32(0).
         */
        bytes32 dstExternalAccount;
        /// @notice The account that will be debited baseToken on the source chain.
        address trader;
        /// @notice The recipient of the quoteToken on the destination chain.
        bytes32 dstTrader;
        /// @notice The token that the trader sells on the source chain.
        address baseToken;
        /// @notice The token that the trader buys on the destination chain.
        bytes32 quoteToken;
        /// @notice The amount of baseToken sold.
        uint256 baseTokenAmount;
        /// @notice The amount of quoteToken bought.
        uint256 quoteTokenAmount;
        /**
         * @notice The Unix timestamp (in seconds) when the quote expire. Only enforced
         * on the source chain.
         */
        /// @dev This gets checked against block.timestamp.
        uint256 quoteExpiry;
        /// @notice Unique identifier for the quote.
        /// @dev Generated off-chain via a distributed UUID generator.
        bytes32 txid;
        /**
         * @notice The address of the IHashflowXChainMessenger contract used for
         * cross-chain communication.
         */
        address xChainMessenger;
        /// @notice Signature provided by the trader (EIP-712).
        bytes takerSignature;
        /// @notice Signature provided by the market maker (EIP-191).
        bytes makerSignature;
    }
}

// File: contracts/pools/HashflowPool.sol



/**
 * SPDX-License-Identifier: UNLICENSED
 */
pragma solidity 0.8.18;

import '@openzeppelin/contracts/proxy/utils/Initializable.sol';
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';
import '@openzeppelin/contracts/utils/cryptography/ECDSA.sol';
import '@openzeppelin/contracts/utils/Context.sol';

import '../interfaces/external/IWETH.sol';
import '../interfaces/IHashflowPool.sol';
import '../interfaces/IHashflowRouter.sol';

interface IERC20AllowanceExtension {
    function increaseAllowance(address spender, uint256 addedValue)
        external
        returns (bool);

    function decreaseAllowance(address spender, uint256 subtractedValue)
        external
        returns (bool);
}

contract HashflowPool is IHashflowPool, Initializable, Context {
    using Address for address payable;
    using SafeERC20 for IERC20;
    using ECDSA for bytes32;

    string public name;

    SignerConfiguration public signerConfiguration;
    address public operations;

    address public router;

    mapping(address => uint256) public nonces;
    mapping(bytes32 => uint256) public xChainNonces;

    mapping(address => bool) internal _withrawalAccountAuth;
    mapping(bytes32 => bool) internal _filledXChainTxids;

    address public immutable _WETH;

    constructor(address weth) {
        require(
            weth != address(0),
            'HashflowPool::constructor WETH cannot be 0 address.'
        );
        _WETH = weth;
    }

    /// @dev Fallback function to receive native token.
    receive() external payable {}

    /// @inheritdoc IHashflowPool
    function initialize(
        string memory _name,
        address _signer,
        address _operations,
        address _router
    ) public override initializer {
        require(
            _signer != address(0),
            'HashflowPool::initialize Signer cannot be 0 address.'
        );
        require(
            _operations != address(0),
            'HashflowPool::initialize Operations cannot be 0 address.'
        );
        require(
            _router != address(0),
            'HashflowPool::initialize Router cannot be 0 address.'
        );
        require(
            bytes(_name).length > 0,
            'HashflowPool::initialize Name cannot be empty'
        );

        name = _name;

        SignerConfiguration memory signerConfig;
        signerConfig.enabled = true;
        signerConfig.signer = _signer;

        emit UpdateSigner(_signer, address(0));

        signerConfiguration = signerConfig;

        operations = _operations;
        router = _router;
    }

    modifier authorizedOperations() {
        require(
            _msgSender() == operations,
            'HashflowPool:authorizedOperations Sender must be operator.'
        );
        _;
    }

    modifier authorizedRouter() {
        require(
            _msgSender() == router,
            'HashflowPool::authorizedRouter Sender must be Router.'
        );
        _;
    }

    /// @inheritdoc IHashflowPool
    function tradeRFQT(RFQTQuote memory quote)
        external
        payable
        override
        authorizedRouter
    {
        /// Trust assumption: the Router has transferred baseToken.
        require(
            quote.baseToken != address(0) ||
                quote.externalAccount != address(0) ||
                msg.value == quote.effectiveBaseTokenAmount,
            'HashflowPool::tradeRFQT msg.value must equal effectiveBaseTokenAmount'
        );
        bytes32 quoteHash = _hashQuoteRFQT(quote);

        SignerConfiguration memory signerConfig = signerConfiguration;
        require(signerConfig.enabled, 'HashflowPool::tradeRFQT Disabled.');

        require(
            quoteHash.recover(quote.signature) == signerConfig.signer,
            'HashflowPool::tradeRFQT Invalid signer.'
        );
        _updateNonce(quote.effectiveTrader, quote.nonce);

        uint256 quoteTokenAmount = quote.quoteTokenAmount;
        if (quote.effectiveBaseTokenAmount < quote.baseTokenAmount) {
            quoteTokenAmount =
                (quote.effectiveBaseTokenAmount * quote.quoteTokenAmount) /
                quote.baseTokenAmount;
        }

        emit Trade(
            quote.trader,
            quote.effectiveTrader,
            quote.txid,
            quote.baseToken,
            quote.quoteToken,
            quote.effectiveBaseTokenAmount,
            quoteTokenAmount
        );

        if (quote.externalAccount == address(0)) {
            _transferFromPool(quote.quoteToken, quote.trader, quoteTokenAmount);
        } else {
            _transferFromExternalAccount(
                quote.externalAccount,
                quote.quoteToken,
                quote.trader,
                quoteTokenAmount
            );
        }
    }

    /// @inheritdoc IHashflowPool
    function tradeRFQM(RFQMQuote memory quote)
        external
        override
        authorizedRouter
    {
        SignerConfiguration memory signerConfig = signerConfiguration;
        require(signerConfig.enabled, 'HashflowPool::tradeRFQM Disabled.');

        bytes32 quoteHash = _hashQuoteRFQM(quote);
        require(
            quoteHash.recover(quote.makerSignature) == signerConfig.signer,
            'HashflowPool::tradeRFQM Invalid signer.'
        );

        emit Trade(
            quote.trader,
            quote.trader,
            quote.txid,
            quote.baseToken,
            quote.quoteToken,
            quote.baseTokenAmount,
            quote.quoteTokenAmount
        );

        if (quote.externalAccount == address(0)) {
            _transferFromPool(
                quote.quoteToken,
                quote.trader,
                quote.quoteTokenAmount
            );
        } else {
            _transferFromExternalAccount(
                quote.externalAccount,
                quote.quoteToken,
                quote.trader,
                quote.quoteTokenAmount
            );
        }
    }

    /// @inheritdoc IHashflowPool
    function tradeXChainRFQT(XChainRFQTQuote memory quote, address trader)
        external
        payable
        override
        authorizedRouter
    {
        require(
            quote.srcExternalAccount != address(0) ||
                quote.baseToken != address(0) ||
                msg.value == quote.effectiveBaseTokenAmount,
            'HashflowPool::tradeXChainRFQT msg.value must = amount'
        );

        SignerConfiguration memory signerConfig = signerConfiguration;
        require(
            signerConfig.enabled,
            'HashflowPool::tradeXChainRFQT Disabled.'
        );

        _updateNonceXChain(quote.dstTrader, quote.nonce);
        bytes32 quoteHash = _hashXChainQuoteRFQT(quote);
        require(
            quoteHash.recover(quote.signature) == signerConfig.signer,
            'HashflowPool::tradeXChainRFQT Invalid signer'
        );

        uint256 effectiveQuoteTokenAmount = quote.quoteTokenAmount;
        if (quote.effectiveBaseTokenAmount < quote.baseTokenAmount) {
            effectiveQuoteTokenAmount =
                (quote.quoteTokenAmount * quote.effectiveBaseTokenAmount) /
                quote.baseTokenAmount;
        }

        emit XChainTrade(
            quote.dstChainId,
            quote.dstPool,
            trader,
            quote.dstTrader,
            quote.txid,
            quote.baseToken,
            quote.quoteToken,
            quote.effectiveBaseTokenAmount,
            effectiveQuoteTokenAmount
        );
    }

    /// @inheritdoc IHashflowPool
    function fillXChain(
        address externalAccount,
        bytes32 txid,
        address trader,
        address quoteToken,
        uint256 quoteTokenAmount
    ) external override authorizedRouter {
        require(
            !_filledXChainTxids[txid],
            'HashflowPool::fillXChain Quote has been executed previously.'
        );
        _filledXChainTxids[txid] = true;

        emit XChainTradeFill(txid);

        if (externalAccount == address(0)) {
            _transferFromPool(quoteToken, trader, quoteTokenAmount);
        } else {
            _transferFromExternalAccount(
                externalAccount,
                quoteToken,
                trader,
                quoteTokenAmount
            );
        }
    }

    /// @inheritdoc IHashflowPool
    function tradeXChainRFQM(XChainRFQMQuote memory quote)
        external
        override
        authorizedRouter
    {
        SignerConfiguration memory signerConfig = signerConfiguration;
        require(
            signerConfig.enabled,
            'HashflowPool::tradeXChainRFQM Disabled.'
        );

        bytes32 quoteHash = _hashXChainQuoteRFQM(quote);
        require(
            quoteHash.recover(quote.makerSignature) == signerConfig.signer,
            'HashflowPool::tradeXChainRFQM Invalid signer'
        );
        emit XChainTrade(
            quote.dstChainId,
            quote.dstPool,
            quote.trader,
            quote.dstTrader,
            quote.txid,
            quote.baseToken,
            quote.quoteToken,
            quote.baseTokenAmount,
            quote.quoteTokenAmount
        );
    }

    /// @inheritdoc IHashflowPool
    function updateXChainPoolAuthorization(
        AuthorizedXChainPool[] calldata pools,
        bool status
    ) external override authorizedOperations {
        for (uint256 i = 0; i < pools.length; i++) {
            require(pools[i].pool != bytes32(0));
            IHashflowRouter(router).updateXChainPoolAuthorization(
                pools[i].chainId,
                pools[i].pool,
                status
            );
        }
    }

    /// @inheritdoc IHashflowPool
    function updateXChainMessengerAuthorization(
        address xChainMessenger,
        bool authorized
    ) external override authorizedOperations {
        require(
            xChainMessenger != address(0),
            'HashflowPool::updateXChainMessengerAuthorization Invalid messenger address.'
        );
        IHashflowRouter(router).updateXChainMessengerAuthorization(
            xChainMessenger,
            authorized
        );
    }

    /// @dev ERC1271 implementation.
    function isValidSignature(bytes32 hash, bytes memory signature)
        external
        view
        override
        returns (bytes4 magicValue)
    {
        if (hash.recover(signature) == signerConfiguration.signer) {
            magicValue = 0x1626ba7e;
        }
    }

    /// @inheritdoc IHashflowPool
    function approveToken(
        address token,
        address spender,
        uint256 amount
    ) external override authorizedOperations {
        IERC20(token).forceApprove(spender, amount);
    }

    /// @inheritdoc IHashflowPool
    function increaseTokenAllowance(
        address token,
        address spender,
        uint256 amount
    ) external override authorizedOperations {
        IERC20(token).safeIncreaseAllowance(spender, amount);
    }

    /// @inheritdoc IHashflowPool
    function decreaseTokenAllowance(
        address token,
        address spender,
        uint256 amount
    ) external override authorizedOperations {
        IERC20(token).safeDecreaseAllowance(spender, amount);
    }

    /// @inheritdoc IHashflowPool
    function removeLiquidity(
        address token,
        address recipient,
        uint256 amount
    ) external override authorizedOperations {
        SignerConfiguration memory signerConfig = signerConfiguration;
        require(
            signerConfig.enabled,
            'HashflowPool::removeLiquidity Disabled.'
        );

        require(amount > 0, 'HashflowPool::removeLiquidity Invalid amount');
        address _recipient;
        if (recipient != address(0)) {
            require(
                _withrawalAccountAuth[recipient],
                'HashflowPool::removeLiquidity Recipient must be hedging account'
            );

            _recipient = recipient;
        } else {
            _recipient = _msgSender();
        }

        emit RemoveLiquidity(token, _recipient, amount);

        _transferFromPool(token, _recipient, amount);
    }

    /// @inheritdoc IHashflowPool
    function updateWithdrawalAccount(
        address[] memory withdrawalAccounts,
        bool authorized
    ) external override authorizedOperations {
        for (uint256 i = 0; i < withdrawalAccounts.length; i++) {
            require(withdrawalAccounts[i] != address(0));
            _withrawalAccountAuth[withdrawalAccounts[i]] = authorized;
            emit UpdateWithdrawalAccount(withdrawalAccounts[i], authorized);
        }
    }

    /// @inheritdoc IHashflowPool
    function updateSigner(address newSigner)
        external
        override
        authorizedOperations
    {
        require(newSigner != address(0));

        SignerConfiguration memory signerConfig = signerConfiguration;

        emit UpdateSigner(newSigner, signerConfig.signer);

        signerConfig.signer = newSigner;
        signerConfiguration = signerConfig;
    }

    /// @inheritdoc IHashflowPool
    function killswitchOperations(bool enabled)
        external
        override
        authorizedRouter
    {
        SignerConfiguration memory signerConfig = signerConfiguration;

        signerConfig.enabled = enabled;

        signerConfiguration = signerConfig;
    }

    function getReserves(address token)
        external
        view
        override
        returns (uint256)
    {
        return _getReserves(token);
    }

    /**
     * @dev Prevents against replay for RFQ-T. Checks that nonces are strictly increasing.
     */
    function _updateNonce(address trader, uint256 nonce) internal {
        require(
            nonce > nonces[trader],
            'HashflowPool::_updateNonce Invalid nonce.'
        );
        nonces[trader] = nonce;
    }

    /**
     * @dev Prevents against replay for X-Chain RFQ-T. Checks that nonces are strictly increasing.
     */
    function _updateNonceXChain(bytes32 trader, uint256 nonce) internal {
        require(
            nonce > xChainNonces[trader],
            'HashflowPool::_updateNonceXChain Invalid nonce.'
        );
        xChainNonces[trader] = nonce;
    }

    function _transferFromPool(
        address token,
        address recipient,
        uint256 value
    ) internal {
        if (token == address(0)) {
            payable(recipient).sendValue(value);
        } else {
            IERC20(token).safeTransfer(recipient, value);
        }
    }

    /// @dev Helper function to transfer quoteToken from external account.
    function _transferFromExternalAccount(
        address externalAccount,
        address token,
        address receiver,
        uint256 value
    ) private {
        if (token == address(0)) {
            IERC20(_WETH).safeTransferFrom(
                externalAccount,
                address(this),
                value
            );

            IWETH(_WETH).withdraw(value);
            payable(receiver).sendValue(value);
        } else {
            IERC20(token).safeTransferFrom(externalAccount, receiver, value);
        }
    }

    function _getReserves(address token) internal view returns (uint256) {
        return
            token == address(0)
                ? address(this).balance
                : IERC20(token).balanceOf(address(this));
    }

    /**
     * @dev Generates a quote hash for RFQ-t.
     */
    function _hashQuoteRFQT(RFQTQuote memory quote)
        private
        view
        returns (bytes32)
    {
        return
            keccak256(
                abi.encodePacked(
                    '\x19Ethereum Signed Message:\n32',
                    keccak256(
                        abi.encodePacked(
                            address(this),
                            quote.trader,
                            quote.effectiveTrader,
                            quote.externalAccount,
                            quote.baseToken,
                            quote.quoteToken,
                            quote.baseTokenAmount,
                            quote.quoteTokenAmount,
                            quote.nonce,
                            quote.quoteExpiry,
                            quote.txid,
                            block.chainid
                        )
                    )
                )
            );
    }

    function _hashQuoteRFQM(RFQMQuote memory quote)
        private
        view
        returns (bytes32)
    {
        return
            keccak256(
                abi.encodePacked(
                    '\x19Ethereum Signed Message:\n32',
                    keccak256(
                        abi.encodePacked(
                            quote.pool,
                            quote.externalAccount,
                            quote.trader,
                            quote.baseToken,
                            quote.quoteToken,
                            quote.baseTokenAmount,
                            quote.quoteTokenAmount,
                            quote.quoteExpiry,
                            quote.txid,
                            block.chainid
                        )
                    )
                )
            );
    }

    function _hashXChainQuoteRFQT(XChainRFQTQuote memory quote)
        private
        pure
        returns (bytes32)
    {
        bytes32 digest = keccak256(
            abi.encodePacked(
                keccak256(
                    abi.encodePacked(
                        quote.srcChainId,
                        quote.dstChainId,
                        quote.srcPool,
                        quote.dstPool,
                        quote.srcExternalAccount,
                        quote.dstExternalAccount
                    )
                ),
                quote.dstTrader,
                quote.baseToken,
                quote.quoteToken,
                quote.baseTokenAmount,
                quote.quoteTokenAmount,
                quote.quoteExpiry,
                quote.nonce,
                quote.txid,
                quote.xChainMessenger
            )
        );
        return
            keccak256(
                abi.encodePacked('\x19Ethereum Signed Message:\n32', digest)
            );
    }

    function _hashXChainQuoteRFQM(XChainRFQMQuote memory quote)
        private
        pure
        returns (bytes32)
    {
        return
            keccak256(
                abi.encodePacked(
                    '\x19Ethereum Signed Message:\n32',
                    keccak256(
                        abi.encodePacked(
                            keccak256(
                                abi.encodePacked(
                                    quote.srcChainId,
                                    quote.dstChainId,
                                    quote.srcPool,
                                    quote.dstPool,
                                    quote.srcExternalAccount,
                                    quote.dstExternalAccount
                                )
                            ),
                            quote.trader,
                            quote.baseToken,
                            quote.quoteToken,
                            quote.baseTokenAmount,
                            quote.quoteTokenAmount,
                            quote.quoteExpiry,
                            quote.txid,
                            quote.xChainMessenger
                        )
                    )
                )
            );
    }
}