pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "../Constants.sol";
contract CommonAdapter {
    using SafeERC20 for IERC20;
    using Address for address;
    using Address for address payable;
    /**
     * @dev Performs a swap
     * @param recipient The original msg.sender performing the swap
     * @param aggregator Address of the aggregator's contract
     * @param spender Address to which tokens will be approved
     * @param method Selector of the function to be called in the aggregator's contract
     * @param tokenFrom Token to be swapped
     * @param tokenTo Token to be received
     * @param amountFrom Amount of tokenFrom to swap
     * @param amountTo Minimum amount of tokenTo to receive
     * @param data Data used for the call made to the aggregator's contract
     */
    function swap(
        address payable recipient,
        address aggregator,
        address spender,
        bytes4 method,
        IERC20 tokenFrom,
        IERC20 tokenTo,
        uint256 amountFrom,
        uint256 amountTo,
        bytes calldata data
    ) external payable {
        require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
        if (address(tokenFrom) != Constants.ETH) {
            _approveSpender(tokenFrom, spender, amountFrom);
        }
        // We always forward msg.value as it may be necessary to pay fees
        bytes memory encodedData = abi.encodePacked(method, data);
        aggregator.functionCallWithValue(encodedData, msg.value);
        // Transfer remaining balance of tokenFrom to sender
        if (address(tokenFrom) != Constants.ETH) {
            uint256 balance = tokenFrom.balanceOf(address(this));
            _transfer(tokenFrom, balance, recipient);
        }
        uint256 weiBalance = address(this).balance;
        // Transfer remaining balance of tokenTo to sender
        if (address(tokenTo) != Constants.ETH) {
            uint256 balance = tokenTo.balanceOf(address(this));
            require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
            _transfer(tokenTo, balance, recipient);
        } else {
            // If tokenTo == ETH, then check that the remaining ETH balance >= amountTo
            require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
        }
        // If there are unused fees or if tokenTo is ETH, transfer to sender
        if (weiBalance > 0) {
            recipient.sendValue(weiBalance);
        }
    }
    /**
     * @dev Transfers token to sender if amount > 0
     * @param token IERC20 token to transfer to sender
     * @param amount Amount of token to transfer
     * @param recipient Address that will receive the tokens
     */
    function _transfer(
        IERC20 token,
        uint256 amount,
        address recipient
    ) internal {
        if (amount > 0) {
            token.safeTransfer(recipient, amount);
        }
    }
    // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
    /**
     * @dev Approves max amount of token to the spender if the allowance is lower than amount
     * @param token The ERC20 token to approve
     * @param spender Address to which funds will be approved
     * @param amount Amount used to compare current allowance
     */
    function _approveSpender(
        IERC20 token,
        address spender,
        uint256 amount
    ) internal {
        // If allowance is not enough, approve max possible amount
        uint256 allowance = token.allowance(address(this), spender);
        if (allowance < amount) {
            bytes memory returndata = address(token).functionCall(
                abi.encodeWithSelector(
                    token.approve.selector,
                    spender,
                    type(uint256).max
                )
            );
            if (returndata.length > 0) {
                // Return data is optional
                require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    using Address for address;
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;
        return c;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }
    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.2;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies in extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return _functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        return _functionCallWithValue(target, data, value, errorMessage);
    }
    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
library Constants {
    address internal constant ETH = 0x0000000000000000000000000000000000000000;
}
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "../Constants.sol";
contract FeeCommonAdapter {
    using SafeERC20 for IERC20;
    using Address for address;
    using Address for address payable;
    using SafeMath for uint256;
    // solhint-disable-next-line var-name-mixedcase
    address payable public immutable FEE_WALLET;
    constructor(address payable feeWallet) public {
        FEE_WALLET = feeWallet;
    }
    /**
     * @dev Performs a swap
     * @param recipient The original msg.sender performing the swap
     * @param aggregator Address of the aggregator's contract
     * @param spender Address to which tokens will be approved
     * @param method Selector of the function to be called in the aggregator's contract
     * @param tokenFrom Token to be swapped
     * @param tokenTo Token to be received
     * @param amountFrom Amount of tokenFrom to swap
     * @param amountTo Minimum amount of tokenTo to receive
     * @param data Data used for the call made to the aggregator's contract
     * @param fee Amount of tokenFrom sent to the fee wallet
     */
    function swap(
        address payable recipient,
        address aggregator,
        address spender,
        bytes4 method,
        IERC20 tokenFrom,
        IERC20 tokenTo,
        uint256 amountFrom,
        uint256 amountTo,
        bytes calldata data,
        uint256 fee
    ) external payable {
        require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
        if (address(tokenFrom) == Constants.ETH) {
            FEE_WALLET.sendValue(fee);
        } else {
            _transfer(tokenFrom, fee, FEE_WALLET);
            _approveSpender(tokenFrom, spender, amountFrom);
        }
        // We always forward msg.value as it may be necessary to pay fees
        aggregator.functionCallWithValue(
            abi.encodePacked(method, data),
            address(this).balance
        );
        // Transfer remaining balance of tokenFrom to sender
        if (address(tokenFrom) != Constants.ETH) {
            _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
        }
        uint256 weiBalance = address(this).balance;
        // Transfer remaining balance of tokenTo to sender
        if (address(tokenTo) != Constants.ETH) {
            uint256 balance = tokenTo.balanceOf(address(this));
            require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
            _transfer(tokenTo, balance, recipient);
        } else {
            // If tokenTo == ETH, then check that the remaining ETH balance >= amountTo
            require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
        }
        // If there are unused fees or if tokenTo is ETH, transfer to sender
        if (weiBalance > 0) {
            recipient.sendValue(weiBalance);
        }
    }
    /**
     * @dev Transfers token to sender if amount > 0
     * @param token IERC20 token to transfer to sender
     * @param amount Amount of token to transfer
     * @param recipient Address that will receive the tokens
     */
    function _transfer(
        IERC20 token,
        uint256 amount,
        address recipient
    ) internal {
        if (amount > 0) {
            token.safeTransfer(recipient, amount);
        }
    }
    // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
    /**
     * @dev Approves max amount of token to the spender if the allowance is lower than amount
     * @param token The ERC20 token to approve
     * @param spender Address to which funds will be approved
     * @param amount Amount used to compare current allowance
     */
    function _approveSpender(
        IERC20 token,
        address spender,
        uint256 amount
    ) internal {
        // If allowance is not enough, approve max possible amount
        uint256 allowance = token.allowance(address(this), spender);
        if (allowance < amount) {
            bytes memory returndata = address(token).functionCall(
                abi.encodeWithSelector(
                    token.approve.selector,
                    spender,
                    type(uint256).max
                )
            );
            if (returndata.length > 0) {
                // Return data is optional
                require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
            }
        }
    }
}
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "../Constants.sol";
import "../IWETH.sol";
contract FeeWethAdapter {
    using SafeERC20 for IERC20;
    using Address for address;
    using Address for address payable;
    using SafeMath for uint256;
    IWETH public immutable weth;
    // solhint-disable-next-line var-name-mixedcase
    address payable public immutable FEE_WALLET;
    constructor(IWETH _weth, address payable feeWallet) public {
        weth = _weth;
        FEE_WALLET = feeWallet;
    }
    /**
     * @dev Performs a swap
     * @param recipient The original msg.sender performing the swap
     * @param aggregator Address of the aggregator's contract
     * @param spender Address to which tokens will be approved
     * @param method Selector of the function to be called in the aggregator's contract
     * @param tokenFrom Token to be swapped
     * @param tokenTo Token to be received
     * @param amountFrom Amount of tokenFrom to swap
     * @param amountTo Minimum amount of tokenTo to receive
     * @param data Data used for the call made to the aggregator's contract
     * @param fee Amount of tokenFrom sent to the fee wallet
     */
    function swap(
        address payable recipient,
        address aggregator,
        address spender,
        bytes4 method,
        IERC20 tokenFrom,
        IERC20 tokenTo,
        uint256 amountFrom,
        uint256 amountTo,
        bytes calldata data,
        uint256 fee
    ) external payable {
        require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
        if (address(tokenFrom) == Constants.ETH) {
            FEE_WALLET.sendValue(fee);
            // If tokenFrom is ETH, msg.value = fee + amountFrom (total fee could be 0)
            // Can't deal with ETH, convert to WETH, the remaining balance will be the fee
            weth.deposit{value: amountFrom}();
            _approveSpender(weth, spender, amountFrom);
        } else {
            _transfer(tokenFrom, fee, FEE_WALLET);
            // Otherwise capture tokens from sender
            _approveSpender(tokenFrom, spender, amountFrom);
        }
        // Perform the swap
        aggregator.functionCallWithValue(
            abi.encodePacked(method, data),
            address(this).balance
        );
        // Transfer remaining balance of tokenFrom to sender
        if (address(tokenFrom) != Constants.ETH) {
            _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
        } else {
            // If using ETH, just unwrap any remaining WETH
            // At the end of this function all ETH will be transferred to the sender
            _unwrapWETH();
        }
        uint256 weiBalance = address(this).balance;
        // Transfer remaining balance of tokenTo to sender
        if (address(tokenTo) != Constants.ETH) {
            uint256 balance = tokenTo.balanceOf(address(this));
            require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
            _transfer(tokenTo, balance, recipient);
        } else {
            // If tokenTo == ETH, unwrap received WETH and add it to the wei balance,
            // then check that the remaining ETH balance >= amountTo
            // It is safe to not use safeMath as no one can have enough Ether to overflow
            weiBalance += _unwrapWETH();
            require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
        }
        // If there are unused fees or if tokenTo is ETH, transfer to sender
        if (weiBalance > 0) {
            recipient.sendValue(weiBalance);
        }
    }
    /**
     * @dev Unwraps all available WETH into ETH
     */
    function _unwrapWETH() internal returns (uint256) {
        uint256 balance = weth.balanceOf(address(this));
        weth.withdraw(balance);
        return balance;
    }
    /**
     * @dev Transfers token to sender if amount > 0
     * @param token IERC20 token to transfer to sender
     * @param amount Amount of token to transfer
     * @param recipient Address that will receive the tokens
     */
    function _transfer(
        IERC20 token,
        uint256 amount,
        address recipient
    ) internal {
        if (amount > 0) {
            token.safeTransfer(recipient, amount);
        }
    }
    // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
    /**
     * @dev Approves max amount of token to the spender if the allowance is lower than amount
     * @param token The ERC20 token to approve
     * @param spender Address to which funds will be approved
     * @param amount Amount used to compare current allowance
     */
    function _approveSpender(
        IERC20 token,
        address spender,
        uint256 amount
    ) internal {
        // If allowance is not enough, approve max possible amount
        uint256 allowance = token.allowance(address(this), spender);
        if (allowance < amount) {
            bytes memory returndata = address(token).functionCall(
                abi.encodeWithSelector(
                    token.approve.selector,
                    spender,
                    type(uint256).max
                )
            );
            if (returndata.length > 0) {
                // Return data is optional
                require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
            }
        }
    }
}
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface IWETH is IERC20 {
    function deposit() external payable;
    function withdraw(uint256) external;
}
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
import "../Constants.sol";
contract UniswapAdapter {
    using SafeERC20 for IERC20;
    using Address for address;
    using Address for address payable;
    using SafeMath for uint256;
    // solhint-disable-next-line var-name-mixedcase
    IUniswapV2Router02 public immutable UNISWAP;
    // solhint-disable-next-line var-name-mixedcase
    address payable public immutable FEE_WALLET;
    constructor(address payable feeWallet, IUniswapV2Router02 uniswap) public {
        FEE_WALLET = feeWallet;
        UNISWAP = uniswap;
    }
    /**
     * @dev Performs a swap
     * @param recipient The original msg.sender performing the swap
     * @param tokenFrom Token to be swapped
     * @param tokenTo Token to be received
     * @param amountFrom Amount of tokenFrom to swap
     * @param amountTo Minimum amount of tokenTo to receive
     * @param path Used by Uniswap
     * @param deadline Timestamp at which the swap becomes invalid. Used by Uniswap
     * @param feeOnTransfer Use `supportingFeeOnTransfer` Uniswap methods
     * @param fee Amount of tokenFrom sent to the fee wallet
     */
    function swap(
        address payable recipient,
        IERC20 tokenFrom,
        IERC20 tokenTo,
        uint256 amountFrom,
        uint256 amountTo,
        address[] calldata path,
        uint256 deadline,
        bool feeOnTransfer,
        uint256 fee
    ) external payable {
        require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
        if (address(tokenFrom) == Constants.ETH) {
            FEE_WALLET.sendValue(fee);
        } else {
            _transfer(tokenFrom, fee, FEE_WALLET);
        }
        if (address(tokenFrom) == Constants.ETH) {
            if (feeOnTransfer) {
                UNISWAP.swapExactETHForTokensSupportingFeeOnTransferTokens{
                    value: address(this).balance
                }(amountTo, path, address(this), deadline);
            } else {
                UNISWAP.swapExactETHForTokens{value: address(this).balance}(
                    amountTo,
                    path,
                    address(this),
                    deadline
                );
            }
        } else {
            _approveSpender(tokenFrom, address(UNISWAP), amountFrom);
            if (address(tokenTo) == Constants.ETH) {
                if (feeOnTransfer) {
                    UNISWAP.swapExactTokensForETHSupportingFeeOnTransferTokens(
                        amountFrom,
                        amountTo,
                        path,
                        address(this),
                        deadline
                    );
                } else {
                    UNISWAP.swapExactTokensForETH(
                        amountFrom,
                        amountTo,
                        path,
                        address(this),
                        deadline
                    );
                }
            } else {
                if (feeOnTransfer) {
                    UNISWAP
                        .swapExactTokensForTokensSupportingFeeOnTransferTokens(
                        amountFrom,
                        amountTo,
                        path,
                        address(this),
                        deadline
                    );
                } else {
                    UNISWAP.swapExactTokensForTokens(
                        amountFrom,
                        amountTo,
                        path,
                        address(this),
                        deadline
                    );
                }
            }
        }
        // Transfer remaining balance of tokenFrom to sender
        if (address(tokenFrom) != Constants.ETH) {
            _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
        }
        uint256 weiBalance = address(this).balance;
        // Transfer remaining balance of tokenTo to sender
        if (address(tokenTo) != Constants.ETH) {
            uint256 balance = tokenTo.balanceOf(address(this));
            require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
            _transfer(tokenTo, balance, recipient);
        } else {
            // If tokenTo == ETH, then check that the remaining ETH balance >= amountTo
            require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
        }
        // If there are unused fees or if tokenTo is ETH, transfer to sender
        if (weiBalance > 0) {
            recipient.sendValue(weiBalance);
        }
    }
    /**
     * @dev Transfers token to sender if amount > 0
     * @param token IERC20 token to transfer to sender
     * @param amount Amount of token to transfer
     * @param recipient Address that will receive the tokens
     */
    function _transfer(
        IERC20 token,
        uint256 amount,
        address recipient
    ) internal {
        if (amount > 0) {
            token.safeTransfer(recipient, amount);
        }
    }
    // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
    /**
     * @dev Approves max amount of token to the spender if the allowance is lower than amount
     * @param token The ERC20 token to approve
     * @param spender Address to which funds will be approved
     * @param amount Amount used to compare current allowance
     */
    function _approveSpender(
        IERC20 token,
        address spender,
        uint256 amount
    ) internal {
        // If allowance is not enough, approve max possible amount
        uint256 allowance = token.allowance(address(this), spender);
        if (allowance < amount) {
            bytes memory returndata = address(token).functionCall(
                abi.encodeWithSelector(
                    token.approve.selector,
                    spender,
                    type(uint256).max
                )
            );
            if (returndata.length > 0) {
                // Return data is optional
                require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
            }
        }
    }
}
pragma solidity >=0.6.2;
import './IUniswapV2Router01.sol';
interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}
pragma solidity >=0.6.2;
interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "../Constants.sol";
import "../IWETH.sol";
contract WethAdapter {
    using SafeERC20 for IERC20;
    using Address for address;
    using Address for address payable;
    IWETH public immutable weth;
    constructor(IWETH _weth) public {
        weth = _weth;
    }
    /**
     * @dev Performs a swap
     * @param recipient The original msg.sender performing the swap
     * @param aggregator Address of the aggregator's contract
     * @param spender Address to which tokens will be approved
     * @param method Selector of the function to be called in the aggregator's contract
     * @param tokenFrom Token to be swapped
     * @param tokenTo Token to be received
     * @param amountFrom Amount of tokenFrom to swap
     * @param amountTo Minimum amount of tokenTo to receive
     * @param data Data used for the call made to the aggregator's contract
     */
    function swap(
        address payable recipient,
        address aggregator,
        address spender,
        bytes4 method,
        IERC20 tokenFrom,
        IERC20 tokenTo,
        uint256 amountFrom,
        uint256 amountTo,
        bytes calldata data
    ) external payable {
        require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
        if (address(tokenFrom) == Constants.ETH) {
            // If tokenFrom is ETH, msg.value = fee + amountFrom (total fee could be 0)
            // Can't deal with ETH, convert to WETH, the remaining balance will be the fee
            weth.deposit{value: amountFrom}();
            _approveSpender(weth, spender, amountFrom);
        } else {
            // Otherwise capture tokens from sender
            _approveSpender(tokenFrom, spender, amountFrom);
        }
        // Perform the swap
        aggregator.functionCallWithValue(
            abi.encodePacked(method, data),
            address(this).balance
        );
        // Transfer remaining balance of tokenFrom to sender
        if (address(tokenFrom) != Constants.ETH) {
            _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
        } else {
            // If using ETH, just unwrap any remaining WETH
            // At the end of this function all ETH will be transferred to the sender
            _unwrapWETH();
        }
        uint256 weiBalance = address(this).balance;
        // Transfer remaining balance of tokenTo to sender
        if (address(tokenTo) != Constants.ETH) {
            uint256 balance = tokenTo.balanceOf(address(this));
            require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
            _transfer(tokenTo, balance, recipient);
        } else {
            // If tokenTo == ETH, unwrap received WETH and add it to the wei balance,
            // then check that the remaining ETH balance >= amountTo
            // It is safe to not use safeMath as no one can have enough Ether to overflow
            weiBalance += _unwrapWETH();
            require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
        }
        // If there are unused fees or if tokenTo is ETH, transfer to sender
        if (weiBalance > 0) {
            recipient.sendValue(weiBalance);
        }
    }
    /**
     * @dev Unwraps all available WETH into ETH
     */
    function _unwrapWETH() internal returns (uint256) {
        uint256 balance = weth.balanceOf(address(this));
        weth.withdraw(balance);
        return balance;
    }
    /**
     * @dev Transfers token to sender if amount > 0
     * @param token IERC20 token to transfer to sender
     * @param amount Amount of token to transfer
     * @param recipient Address that will receive the tokens
     */
    function _transfer(
        IERC20 token,
        uint256 amount,
        address recipient
    ) internal {
        if (amount > 0) {
            token.safeTransfer(recipient, amount);
        }
    }
    // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
    /**
     * @dev Approves max amount of token to the spender if the allowance is lower than amount
     * @param token The ERC20 token to approve
     * @param spender Address to which funds will be approved
     * @param amount Amount used to compare current allowance
     */
    function _approveSpender(
        IERC20 token,
        address spender,
        uint256 amount
    ) internal {
        // If allowance is not enough, approve max possible amount
        uint256 allowance = token.allowance(address(this), spender);
        if (allowance < amount) {
            bytes memory returndata = address(token).functionCall(
                abi.encodeWithSelector(
                    token.approve.selector,
                    spender,
                    type(uint256).max
                )
            );
            if (returndata.length > 0) {
                // Return data is optional
                require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface ICHI is IERC20 {
    function freeUpTo(uint256 value) external returns (uint256);
    function freeFromUpTo(
        address from,
        uint256 value
    ) external returns (uint256);
    function mint(uint256 value) external;
}
  
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.6.0;
// We import the contract so truffle compiles it, and we have the ABI
// available when working from truffle console.
import "@openzeppelin/contracts/token/ERC20/ERC20.sol"; //helpers// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "../../GSN/Context.sol";
import "./IERC20.sol";
import "../../math/SafeMath.sol";
import "../../utils/Address.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;
    using Address for address;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals;
    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name, string memory symbol) public {
        _name = name;
        _symbol = symbol;
        _decimals = 18;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view returns (uint8) {
        return _decimals;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }
    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(sender, recipient, amount);
        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal {
        _decimals = decimals_;
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/*
 * @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 GSN 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 payable) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Pausable.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./ICHI.sol";
import "./Spender.sol";
/**
 * @title MetaSwap
 */
contract MetaSwap is Ownable, Pausable, ReentrancyGuard {
    using SafeERC20 for IERC20;
    using Address for address;
    using Address for address payable;
    struct Adapter {
        address addr; // adapter's address
        bytes4 selector;
        bytes data; // adapter's fixed data
    }
    ICHI public immutable chi;
    Spender public immutable spender;
    // Mapping of aggregatorId to aggregator
    mapping(string => Adapter) public adapters;
    mapping(string => bool) public adapterRemoved;
    event AdapterSet(
        string indexed aggregatorId,
        address indexed addr,
        bytes4 selector,
        bytes data
    );
    event AdapterRemoved(string indexed aggregatorId);
    event Swap(string indexed aggregatorId, address indexed sender);
    constructor(ICHI _chi) public {
        chi = _chi;
        spender = new Spender();
    }
    /**
     * @dev Sets the adapter for an aggregator. It can't be changed later.
     * @param aggregatorId Aggregator's identifier
     * @param addr Address of the contract that contains the logic for this aggregator
     * @param selector The function selector of the swap function in the adapter
     * @param data Fixed abi encoded data the will be passed in each delegatecall made to the adapter
     */
    function setAdapter(
        string calldata aggregatorId,
        address addr,
        bytes4 selector,
        bytes calldata data
    ) external onlyOwner {
        require(addr.isContract(), "ADAPTER_IS_NOT_A_CONTRACT");
        require(!adapterRemoved[aggregatorId], "ADAPTER_REMOVED");
        Adapter storage adapter = adapters[aggregatorId];
        require(adapter.addr == address(0), "ADAPTER_EXISTS");
        adapter.addr = addr;
        adapter.selector = selector;
        adapter.data = data;
        emit AdapterSet(aggregatorId, addr, selector, data);
    }
    /**
     * @dev Removes the adapter for an existing aggregator. This can't be undone.
     * @param aggregatorId Aggregator's identifier
     */
    function removeAdapter(string calldata aggregatorId) external onlyOwner {
        require(
            adapters[aggregatorId].addr != address(0),
            "ADAPTER_DOES_NOT_EXIST"
        );
        delete adapters[aggregatorId];
        adapterRemoved[aggregatorId] = true;
        emit AdapterRemoved(aggregatorId);
    }
    /**
     * @dev Performs a swap
     * @param aggregatorId Identifier of the aggregator to be used for the swap
     * @param data Dynamic data which is concatenated with the fixed aggregator's
     * data in the delecatecall made to the adapter
     */
    function swap(
        string calldata aggregatorId,
        IERC20 tokenFrom,
        uint256 amount,
        bytes calldata data
    ) external payable whenNotPaused nonReentrant {
        _swap(aggregatorId, tokenFrom, amount, data);
    }
    /**
     * @dev Performs a swap
     * @param aggregatorId Identifier of the aggregator to be used for the swap
     * @param data Dynamic data which is concatenated with the fixed aggregator's
     * data in the delecatecall made to the adapter
     */
    function swapUsingGasToken(
        string calldata aggregatorId,
        IERC20 tokenFrom,
        uint256 amount,
        bytes calldata data
    ) external payable whenNotPaused nonReentrant {
        uint256 gas = gasleft();
        _swap(aggregatorId, tokenFrom, amount, data);
        uint256 gasSpent = 21000 + gas - gasleft() + 16 * msg.data.length;
        chi.freeFromUpTo(msg.sender, (gasSpent + 14154) / 41947);
    }
    function pauseSwaps() external onlyOwner {
        _pause();
    }
    function unpauseSwaps() external onlyOwner {
        _unpause();
    }
    function _swap(
        string calldata aggregatorId,
        IERC20 tokenFrom,
        uint256 amount,
        bytes calldata data
    ) internal {
        Adapter storage adapter = adapters[aggregatorId];
        if (address(tokenFrom) != Constants.ETH) {
            tokenFrom.safeTransferFrom(msg.sender, address(spender), amount);
        }
        spender.swap{value: msg.value}(
            adapter.addr,
            abi.encodePacked(
                adapter.selector,
                abi.encode(msg.sender),
                adapter.data,
                data
            )
        );
        emit Swap(aggregatorId, msg.sender);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "../GSN/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "../GSN/Context.sol";
/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);
    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);
    bool private _paused;
    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor () internal {
        _paused = false;
    }
    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view returns (bool) {
        return _paused;
    }
    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        require(!_paused, "Pausable: paused");
        _;
    }
    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        require(_paused, "Pausable: not paused");
        _;
    }
    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }
    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;
    uint256 private _status;
    constructor () internal {
        _status = _NOT_ENTERED;
    }
    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "./Constants.sol";
contract Spender {
    address public immutable metaswap;
    constructor() public {
        metaswap = msg.sender;
    }
    /// @dev Receives ether from swaps
    fallback() external payable {}
    function swap(address adapter, bytes calldata data) external payable {
        require(msg.sender == metaswap, "FORBIDDEN");
        require(adapter != address(0), "ADAPTER_NOT_PROVIDED");
        _delegate(adapter, data, "ADAPTER_DELEGATECALL_FAILED");
    }
    /**
     * @dev Performs a delegatecall and bubbles up the errors, adapted from
     * https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Address.sol
     * @param target Address of the contract to delegatecall
     * @param data Data passed in the delegatecall
     * @param errorMessage Fallback revert reason
     */
    function _delegate(
        address target,
        bytes memory data,
        string memory errorMessage
    ) private returns (bytes memory) {
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
pragma solidity ^0.6.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
contract MockAdapter {
    using SafeERC20 for IERC20;
    using Address for address;
    using Address for address payable;
    event MockAdapterEvent(
        address sender,
        uint256 valueFixed,
        uint256 valueDynamic
    );
    function test(
        address sender,
        uint256 valueFixed,
        uint256 valueDynamic
    ) external payable {
        emit MockAdapterEvent(sender, valueFixed, valueDynamic);
    }
    function testRevert(
        address,
        uint256,
        uint256
    ) external payable {
        revert("SWAP_FAILED");
    }
    function testRevertNoReturnData(
        address,
        uint256,
        uint256
    ) external payable {
        revert();
    }
}
pragma solidity ^0.6.0;
// TAKEN FROM https://github.com/gnosis/mock-contract
// TODO: use their npm package once it is published for solidity 0.6
interface MockInterface {
    /**
     * @dev After calling this method, the mock will return `response` when it is called
     * with any calldata that is not mocked more specifically below
     * (e.g. using givenMethodReturn).
     * @param response ABI encoded response that will be returned if method is invoked
     */
    function givenAnyReturn(bytes calldata response) external;
    function givenAnyReturnBool(bool response) external;
    function givenAnyReturnUint(uint256 response) external;
    function givenAnyReturnAddress(address response) external;
    function givenAnyRevert() external;
    function givenAnyRevertWithMessage(string calldata message) external;
    function givenAnyRunOutOfGas() external;
    /**
     * @dev After calling this method, the mock will return `response` when the given
     * methodId is called regardless of arguments. If the methodId and arguments
     * are mocked more specifically (using `givenMethodAndArguments`) the latter
     * will take precedence.
     * @param method ABI encoded methodId. It is valid to pass full calldata (including arguments). The mock will extract the methodId from it
     * @param response ABI encoded response that will be returned if method is invoked
     */
    function givenMethodReturn(bytes calldata method, bytes calldata response)
        external;
    function givenMethodReturnBool(bytes calldata method, bool response)
        external;
    function givenMethodReturnUint(bytes calldata method, uint256 response)
        external;
    function givenMethodReturnAddress(bytes calldata method, address response)
        external;
    function givenMethodRevert(bytes calldata method) external;
    function givenMethodRevertWithMessage(
        bytes calldata method,
        string calldata message
    ) external;
    function givenMethodRunOutOfGas(bytes calldata method) external;
    /**
     * @dev After calling this method, the mock will return `response` when the given
     * methodId is called with matching arguments. These exact calldataMocks will take
     * precedence over all other calldataMocks.
     * @param call ABI encoded calldata (methodId and arguments)
     * @param response ABI encoded response that will be returned if contract is invoked with calldata
     */
    function givenCalldataReturn(bytes calldata call, bytes calldata response)
        external;
    function givenCalldataReturnBool(bytes calldata call, bool response)
        external;
    function givenCalldataReturnUint(bytes calldata call, uint256 response)
        external;
    function givenCalldataReturnAddress(bytes calldata call, address response)
        external;
    function givenCalldataRevert(bytes calldata call) external;
    function givenCalldataRevertWithMessage(
        bytes calldata call,
        string calldata message
    ) external;
    function givenCalldataRunOutOfGas(bytes calldata call) external;
    /**
     * @dev Returns the number of times anything has been called on this mock since last reset
     */
    function invocationCount() external returns (uint256);
    /**
     * @dev Returns the number of times the given method has been called on this mock since last reset
     * @param method ABI encoded methodId. It is valid to pass full calldata (including arguments). The mock will extract the methodId from it
     */
    function invocationCountForMethod(bytes calldata method)
        external
        returns (uint256);
    /**
     * @dev Returns the number of times this mock has been called with the exact calldata since last reset.
     * @param call ABI encoded calldata (methodId and arguments)
     */
    function invocationCountForCalldata(bytes calldata call)
        external
        returns (uint256);
    /**
     * @dev Resets all mocked methods and invocation counts.
     */
    function reset() external;
}
/**
 * Implementation of the MockInterface.
 */
contract MockContract is MockInterface {
    enum MockType {Return, Revert, OutOfGas}
    bytes32 public constant MOCKS_LIST_START = hex"01";
    bytes public constant MOCKS_LIST_END = "0xff";
    bytes32 public constant MOCKS_LIST_END_HASH = keccak256(MOCKS_LIST_END);
    bytes4 public constant SENTINEL_ANY_MOCKS = hex"01";
    bytes public constant DEFAULT_FALLBACK_VALUE = abi.encode(false);
    // A linked list allows easy iteration and inclusion checks
    mapping(bytes32 => bytes) calldataMocks;
    mapping(bytes => MockType) calldataMockTypes;
    mapping(bytes => bytes) calldataExpectations;
    mapping(bytes => string) calldataRevertMessage;
    mapping(bytes32 => uint256) calldataInvocations;
    mapping(bytes4 => bytes4) methodIdMocks;
    mapping(bytes4 => MockType) methodIdMockTypes;
    mapping(bytes4 => bytes) methodIdExpectations;
    mapping(bytes4 => string) methodIdRevertMessages;
    mapping(bytes32 => uint256) methodIdInvocations;
    MockType fallbackMockType;
    bytes fallbackExpectation = DEFAULT_FALLBACK_VALUE;
    string fallbackRevertMessage;
    uint256 invocations;
    uint256 resetCount;
    constructor() public {
        calldataMocks[MOCKS_LIST_START] = MOCKS_LIST_END;
        methodIdMocks[SENTINEL_ANY_MOCKS] = SENTINEL_ANY_MOCKS;
    }
    function trackCalldataMock(bytes memory call) private {
        bytes32 callHash = keccak256(call);
        if (calldataMocks[callHash].length == 0) {
            calldataMocks[callHash] = calldataMocks[MOCKS_LIST_START];
            calldataMocks[MOCKS_LIST_START] = call;
        }
    }
    function trackMethodIdMock(bytes4 methodId) private {
        if (methodIdMocks[methodId] == 0x0) {
            methodIdMocks[methodId] = methodIdMocks[SENTINEL_ANY_MOCKS];
            methodIdMocks[SENTINEL_ANY_MOCKS] = methodId;
        }
    }
    function _givenAnyReturn(bytes memory response) internal {
        fallbackMockType = MockType.Return;
        fallbackExpectation = response;
    }
    function givenAnyReturn(bytes calldata response) external override {
        _givenAnyReturn(response);
    }
    function givenAnyReturnBool(bool response) external override {
        uint256 flag = response ? 1 : 0;
        _givenAnyReturn(uintToBytes(flag));
    }
    function givenAnyReturnUint(uint256 response) external override {
        _givenAnyReturn(uintToBytes(response));
    }
    function givenAnyReturnAddress(address response) external override {
        _givenAnyReturn(uintToBytes(uint256(response)));
    }
    function givenAnyRevert() external override {
        fallbackMockType = MockType.Revert;
        fallbackRevertMessage = "";
    }
    function givenAnyRevertWithMessage(string calldata message)
        external
        override
    {
        fallbackMockType = MockType.Revert;
        fallbackRevertMessage = message;
    }
    function givenAnyRunOutOfGas() external override {
        fallbackMockType = MockType.OutOfGas;
    }
    function _givenCalldataReturn(bytes memory call, bytes memory response)
        private
    {
        calldataMockTypes[call] = MockType.Return;
        calldataExpectations[call] = response;
        trackCalldataMock(call);
    }
    function givenCalldataReturn(bytes calldata call, bytes calldata response)
        external
        override
    {
        _givenCalldataReturn(call, response);
    }
    function givenCalldataReturnBool(bytes calldata call, bool response)
        external
        override
    {
        uint256 flag = response ? 1 : 0;
        _givenCalldataReturn(call, uintToBytes(flag));
    }
    function givenCalldataReturnUint(bytes calldata call, uint256 response)
        external
        override
    {
        _givenCalldataReturn(call, uintToBytes(response));
    }
    function givenCalldataReturnAddress(bytes calldata call, address response)
        external
        override
    {
        _givenCalldataReturn(call, uintToBytes(uint256(response)));
    }
    function _givenMethodReturn(bytes memory call, bytes memory response)
        private
    {
        bytes4 method = bytesToBytes4(call);
        methodIdMockTypes[method] = MockType.Return;
        methodIdExpectations[method] = response;
        trackMethodIdMock(method);
    }
    function givenMethodReturn(bytes calldata call, bytes calldata response)
        external
        override
    {
        _givenMethodReturn(call, response);
    }
    function givenMethodReturnBool(bytes calldata call, bool response)
        external
        override
    {
        uint256 flag = response ? 1 : 0;
        _givenMethodReturn(call, uintToBytes(flag));
    }
    function givenMethodReturnUint(bytes calldata call, uint256 response)
        external
        override
    {
        _givenMethodReturn(call, uintToBytes(response));
    }
    function givenMethodReturnAddress(bytes calldata call, address response)
        external
        override
    {
        _givenMethodReturn(call, uintToBytes(uint256(response)));
    }
    function givenCalldataRevert(bytes calldata call) external override {
        calldataMockTypes[call] = MockType.Revert;
        calldataRevertMessage[call] = "";
        trackCalldataMock(call);
    }
    function givenMethodRevert(bytes calldata call) external override {
        bytes4 method = bytesToBytes4(call);
        methodIdMockTypes[method] = MockType.Revert;
        trackMethodIdMock(method);
    }
    function givenCalldataRevertWithMessage(
        bytes calldata call,
        string calldata message
    ) external override {
        calldataMockTypes[call] = MockType.Revert;
        calldataRevertMessage[call] = message;
        trackCalldataMock(call);
    }
    function givenMethodRevertWithMessage(
        bytes calldata call,
        string calldata message
    ) external override {
        bytes4 method = bytesToBytes4(call);
        methodIdMockTypes[method] = MockType.Revert;
        methodIdRevertMessages[method] = message;
        trackMethodIdMock(method);
    }
    function givenCalldataRunOutOfGas(bytes calldata call) external override {
        calldataMockTypes[call] = MockType.OutOfGas;
        trackCalldataMock(call);
    }
    function givenMethodRunOutOfGas(bytes calldata call) external override {
        bytes4 method = bytesToBytes4(call);
        methodIdMockTypes[method] = MockType.OutOfGas;
        trackMethodIdMock(method);
    }
    function invocationCount() external override returns (uint256) {
        return invocations;
    }
    function invocationCountForMethod(bytes calldata call)
        external
        override
        returns (uint256)
    {
        bytes4 method = bytesToBytes4(call);
        return
            methodIdInvocations[keccak256(
                abi.encodePacked(resetCount, method)
            )];
    }
    function invocationCountForCalldata(bytes calldata call)
        external
        override
        returns (uint256)
    {
        return
            calldataInvocations[keccak256(abi.encodePacked(resetCount, call))];
    }
    function reset() external override {
        // Reset all exact calldataMocks
        bytes memory nextMock = calldataMocks[MOCKS_LIST_START];
        bytes32 mockHash = keccak256(nextMock);
        // We cannot compary bytes
        while (mockHash != MOCKS_LIST_END_HASH) {
            // Reset all mock maps
            calldataMockTypes[nextMock] = MockType.Return;
            calldataExpectations[nextMock] = hex"";
            calldataRevertMessage[nextMock] = "";
            // Set next mock to remove
            nextMock = calldataMocks[mockHash];
            // Remove from linked list
            calldataMocks[mockHash] = "";
            // Update mock hash
            mockHash = keccak256(nextMock);
        }
        // Clear list
        calldataMocks[MOCKS_LIST_START] = MOCKS_LIST_END;
        // Reset all any calldataMocks
        bytes4 nextAnyMock = methodIdMocks[SENTINEL_ANY_MOCKS];
        while (nextAnyMock != SENTINEL_ANY_MOCKS) {
            bytes4 currentAnyMock = nextAnyMock;
            methodIdMockTypes[currentAnyMock] = MockType.Return;
            methodIdExpectations[currentAnyMock] = hex"";
            methodIdRevertMessages[currentAnyMock] = "";
            nextAnyMock = methodIdMocks[currentAnyMock];
            // Remove from linked list
            methodIdMocks[currentAnyMock] = 0x0;
        }
        // Clear list
        methodIdMocks[SENTINEL_ANY_MOCKS] = SENTINEL_ANY_MOCKS;
        fallbackExpectation = DEFAULT_FALLBACK_VALUE;
        fallbackMockType = MockType.Return;
        invocations = 0;
        resetCount += 1;
    }
    function useAllGas() private {
        while (true) {
            bool s;
            assembly {
                //expensive call to EC multiply contract
                s := call(sub(gas(), 2000), 6, 0, 0x0, 0xc0, 0x0, 0x60)
            }
        }
    }
    function bytesToBytes4(bytes memory b) private pure returns (bytes4) {
        bytes4 out;
        for (uint256 i = 0; i < 4; i++) {
            out |= bytes4(b[i] & 0xFF) >> (i * 8);
        }
        return out;
    }
    function uintToBytes(uint256 x) private pure returns (bytes memory b) {
        b = new bytes(32);
        assembly {
            mstore(add(b, 32), x)
        }
    }
    function updateInvocationCount(
        bytes4 methodId,
        bytes memory originalMsgData
    ) public {
        require(
            msg.sender == address(this),
            "Can only be called from the contract itself"
        );
        invocations += 1;
        methodIdInvocations[keccak256(
            abi.encodePacked(resetCount, methodId)
        )] += 1;
        calldataInvocations[keccak256(
            abi.encodePacked(resetCount, originalMsgData)
        )] += 1;
    }
    fallback() external payable {
        bytes4 methodId;
        assembly {
            methodId := calldataload(0)
        }
        // First, check exact matching overrides
        if (calldataMockTypes[msg.data] == MockType.Revert) {
            revert(calldataRevertMessage[msg.data]);
        }
        if (calldataMockTypes[msg.data] == MockType.OutOfGas) {
            useAllGas();
        }
        bytes memory result = calldataExpectations[msg.data];
        // Then check method Id overrides
        if (result.length == 0) {
            if (methodIdMockTypes[methodId] == MockType.Revert) {
                revert(methodIdRevertMessages[methodId]);
            }
            if (methodIdMockTypes[methodId] == MockType.OutOfGas) {
                useAllGas();
            }
            result = methodIdExpectations[methodId];
        }
        // Last, use the fallback override
        if (result.length == 0) {
            if (fallbackMockType == MockType.Revert) {
                revert(fallbackRevertMessage);
            }
            if (fallbackMockType == MockType.OutOfGas) {
                useAllGas();
            }
            result = fallbackExpectation;
        }
        // Record invocation as separate call so we don't rollback in case we are called with STATICCALL
        (, bytes memory r) = address(this).call{gas: 100000}(
            abi.encodeWithSignature(
                "updateInvocationCount(bytes4,bytes)",
                methodId,
                msg.data
            )
        );
        assert(r.length == 0);
        assembly {
            return(add(0x20, result), mload(result))
        }
    }
}
pragma solidity ^0.6.0;
contract MockSelfDestruct {
    constructor() public payable {}
    fallback() external payable {
        selfdestruct(msg.sender);
    }
    function kill(address payable target) external payable {
        selfdestruct(target);
    }
}

pragma solidity ^0.4.24;

// File: zos-lib/contracts/upgradeability/Proxy.sol

/**
 * @title Proxy
 * @dev Implements delegation of calls to other contracts, with proper
 * forwarding of return values and bubbling of failures.
 * It defines a fallback function that delegates all calls to the address
 * returned by the abstract _implementation() internal function.
 */
contract Proxy {
  /**
   * @dev Fallback function.
   * Implemented entirely in `_fallback`.
   */
  function () payable external {
    _fallback();
  }

  /**
   * @return The Address of the implementation.
   */
  function _implementation() internal view returns (address);

  /**
   * @dev Delegates execution to an implementation contract.
   * This is a low level function that doesn't return to its internal call site.
   * It will return to the external caller whatever the implementation returns.
   * @param implementation Address to delegate.
   */
  function _delegate(address implementation) internal {
    assembly {
      // Copy msg.data. We take full control of memory in this inline assembly
      // block because it will not return to Solidity code. We overwrite the
      // Solidity scratch pad at memory position 0.
      calldatacopy(0, 0, calldatasize)

      // Call the implementation.
      // out and outsize are 0 because we don't know the size yet.
      let result := delegatecall(gas, implementation, 0, calldatasize, 0, 0)

      // Copy the returned data.
      returndatacopy(0, 0, returndatasize)

      switch result
      // delegatecall returns 0 on error.
      case 0 { revert(0, returndatasize) }
      default { return(0, returndatasize) }
    }
  }

  /**
   * @dev Function that is run as the first thing in the fallback function.
   * Can be redefined in derived contracts to add functionality.
   * Redefinitions must call super._willFallback().
   */
  function _willFallback() internal {
  }

  /**
   * @dev fallback implementation.
   * Extracted to enable manual triggering.
   */
  function _fallback() internal {
    _willFallback();
    _delegate(_implementation());
  }
}

// File: openzeppelin-solidity/contracts/AddressUtils.sol

/**
 * Utility library of inline functions on addresses
 */
library AddressUtils {

  /**
   * Returns whether the target address is a contract
   * @dev This function will return false if invoked during the constructor of a contract,
   * as the code is not actually created until after the constructor finishes.
   * @param addr address to check
   * @return whether the target address is a contract
   */
  function isContract(address addr) internal view returns (bool) {
    uint256 size;
    // XXX Currently there is no better way to check if there is a contract in an address
    // than to check the size of the code at that address.
    // See https://ethereum.stackexchange.com/a/14016/36603
    // for more details about how this works.
    // TODO Check this again before the Serenity release, because all addresses will be
    // contracts then.
    // solium-disable-next-line security/no-inline-assembly
    assembly { size := extcodesize(addr) }
    return size > 0;
  }

}

// File: zos-lib/contracts/upgradeability/UpgradeabilityProxy.sol

/**
 * @title UpgradeabilityProxy
 * @dev This contract implements a proxy that allows to change the
 * implementation address to which it will delegate.
 * Such a change is called an implementation upgrade.
 */
contract UpgradeabilityProxy is Proxy {
  /**
   * @dev Emitted when the implementation is upgraded.
   * @param implementation Address of the new implementation.
   */
  event Upgraded(address implementation);

  /**
   * @dev Storage slot with the address of the current implementation.
   * This is the keccak-256 hash of "org.zeppelinos.proxy.implementation", and is
   * validated in the constructor.
   */
  bytes32 private constant IMPLEMENTATION_SLOT = 0x7050c9e0f4ca769c69bd3a8ef740bc37934f8e2c036e5a723fd8ee048ed3f8c3;

  /**
   * @dev Contract constructor.
   * @param _implementation Address of the initial implementation.
   */
  constructor(address _implementation) public {
    assert(IMPLEMENTATION_SLOT == keccak256("org.zeppelinos.proxy.implementation"));

    _setImplementation(_implementation);
  }

  /**
   * @dev Returns the current implementation.
   * @return Address of the current implementation
   */
  function _implementation() internal view returns (address impl) {
    bytes32 slot = IMPLEMENTATION_SLOT;
    assembly {
      impl := sload(slot)
    }
  }

  /**
   * @dev Upgrades the proxy to a new implementation.
   * @param newImplementation Address of the new implementation.
   */
  function _upgradeTo(address newImplementation) internal {
    _setImplementation(newImplementation);
    emit Upgraded(newImplementation);
  }

  /**
   * @dev Sets the implementation address of the proxy.
   * @param newImplementation Address of the new implementation.
   */
  function _setImplementation(address newImplementation) private {
    require(AddressUtils.isContract(newImplementation), "Cannot set a proxy implementation to a non-contract address");

    bytes32 slot = IMPLEMENTATION_SLOT;

    assembly {
      sstore(slot, newImplementation)
    }
  }
}

// File: zos-lib/contracts/upgradeability/AdminUpgradeabilityProxy.sol

/**
 * @title AdminUpgradeabilityProxy
 * @dev This contract combines an upgradeability proxy with an authorization
 * mechanism for administrative tasks.
 * All external functions in this contract must be guarded by the
 * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
 * feature proposal that would enable this to be done automatically.
 */
contract AdminUpgradeabilityProxy is UpgradeabilityProxy {
  /**
   * @dev Emitted when the administration has been transferred.
   * @param previousAdmin Address of the previous admin.
   * @param newAdmin Address of the new admin.
   */
  event AdminChanged(address previousAdmin, address newAdmin);

  /**
   * @dev Storage slot with the admin of the contract.
   * This is the keccak-256 hash of "org.zeppelinos.proxy.admin", and is
   * validated in the constructor.
   */
  bytes32 private constant ADMIN_SLOT = 0x10d6a54a4754c8869d6886b5f5d7fbfa5b4522237ea5c60d11bc4e7a1ff9390b;

  /**
   * @dev Modifier to check whether the `msg.sender` is the admin.
   * If it is, it will run the function. Otherwise, it will delegate the call
   * to the implementation.
   */
  modifier ifAdmin() {
    if (msg.sender == _admin()) {
      _;
    } else {
      _fallback();
    }
  }

  /**
   * Contract constructor.
   * It sets the `msg.sender` as the proxy administrator.
   * @param _implementation address of the initial implementation.
   */
  constructor(address _implementation) UpgradeabilityProxy(_implementation) public {
    assert(ADMIN_SLOT == keccak256("org.zeppelinos.proxy.admin"));

    _setAdmin(msg.sender);
  }

  /**
   * @return The address of the proxy admin.
   */
  function admin() external view ifAdmin returns (address) {
    return _admin();
  }

  /**
   * @return The address of the implementation.
   */
  function implementation() external view ifAdmin returns (address) {
    return _implementation();
  }

  /**
   * @dev Changes the admin of the proxy.
   * Only the current admin can call this function.
   * @param newAdmin Address to transfer proxy administration to.
   */
  function changeAdmin(address newAdmin) external ifAdmin {
    require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address");
    emit AdminChanged(_admin(), newAdmin);
    _setAdmin(newAdmin);
  }

  /**
   * @dev Upgrade the backing implementation of the proxy.
   * Only the admin can call this function.
   * @param newImplementation Address of the new implementation.
   */
  function upgradeTo(address newImplementation) external ifAdmin {
    _upgradeTo(newImplementation);
  }

  /**
   * @dev Upgrade the backing implementation of the proxy and call a function
   * on the new implementation.
   * This is useful to initialize the proxied contract.
   * @param newImplementation Address of the new implementation.
   * @param data Data to send as msg.data in the low level call.
   * It should include the signature and the parameters of the function to be
   * called, as described in
   * https://solidity.readthedocs.io/en/develop/abi-spec.html#function-selector-and-argument-encoding.
   */
  function upgradeToAndCall(address newImplementation, bytes data) payable external ifAdmin {
    _upgradeTo(newImplementation);
    require(address(this).call.value(msg.value)(data));
  }

  /**
   * @return The admin slot.
   */
  function _admin() internal view returns (address adm) {
    bytes32 slot = ADMIN_SLOT;
    assembly {
      adm := sload(slot)
    }
  }

  /**
   * @dev Sets the address of the proxy admin.
   * @param newAdmin Address of the new proxy admin.
   */
  function _setAdmin(address newAdmin) internal {
    bytes32 slot = ADMIN_SLOT;

    assembly {
      sstore(slot, newAdmin)
    }
  }

  /**
   * @dev Only fall back when the sender is not the admin.
   */
  function _willFallback() internal {
    require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin");
    super._willFallback();
  }
}

// File: contracts/FiatTokenProxy.sol

/**
* Copyright CENTRE SECZ 2018
*
* Permission is hereby granted, free of charge, to any person obtaining a copy 
* of this software and associated documentation files (the "Software"), to deal 
* in the Software without restriction, including without limitation the rights 
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
* copies of the Software, and to permit persons to whom the Software is furnished to 
* do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all 
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

pragma solidity ^0.4.24;


/**
 * @title FiatTokenProxy
 * @dev This contract proxies FiatToken calls and enables FiatToken upgrades
*/ 
contract FiatTokenProxy is AdminUpgradeabilityProxy {
    constructor(address _implementation) public AdminUpgradeabilityProxy(_implementation) {
    }
}

{"Constants.84ef19f8.sol":{"content":"// SPDX-License-Identifier: MIT\r\n\r\npragma solidity ^0.6.0;\r\n\r\nlibrary Constants {\r\n    address internal constant ETH = 0x0000000000000000000000000000000000000000;\r\n}\r\n"},"Spender.3372a096.sol":{"content":"// SPDX-License-Identifier: MIT\r\n\r\npragma solidity ^0.6.0;\r\n\r\nimport \"./Constants.84ef19f8.sol\";\r\n\r\ncontract Spender {\r\n    address public immutable metaswap;\r\n\r\n    constructor() public {\r\n        metaswap = msg.sender;\r\n    }\r\n\r\n    /// @dev Receives ether from swaps\r\n    fallback() external payable {}\r\n\r\n    function swap(address adapter, bytes calldata data) external payable {\r\n        require(msg.sender == metaswap, \"FORBIDDEN\");\r\n        require(adapter != address(0), \"ADAPTER_NOT_PROVIDED\");\r\n        _delegate(adapter, data, \"ADAPTER_DELEGATECALL_FAILED\");\r\n    }\r\n\r\n    /**\r\n     * @dev Performs a delegatecall and bubbles up the errors, adapted from\r\n     * https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Address.sol\r\n     * @param target Address of the contract to delegatecall\r\n     * @param data Data passed in the delegatecall\r\n     * @param errorMessage Fallback revert reason\r\n     */\r\n    function _delegate(\r\n        address target,\r\n        bytes memory data,\r\n        string memory errorMessage\r\n    ) private returns (bytes memory) {\r\n        // solhint-disable-next-line avoid-low-level-calls\r\n        (bool success, bytes memory returndata) = target.delegatecall(data);\r\n        if (success) {\r\n            return returndata;\r\n        } else {\r\n            // Look for revert reason and bubble it up if present\r\n            if (returndata.length \u003e 0) {\r\n                // The easiest way to bubble the revert reason is using memory via assembly\r\n\r\n                // solhint-disable-next-line no-inline-assembly\r\n                assembly {\r\n                    let returndata_size := mload(returndata)\r\n                    revert(add(32, returndata), returndata_size)\r\n                }\r\n            } else {\r\n                revert(errorMessage);\r\n            }\r\n        }\r\n    }\r\n}\r\n"}}

pragma solidity ^0.4.17;

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        assert(c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        // assert(b > 0); // Solidity automatically throws when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        assert(b <= a);
        return a - b;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        assert(c >= a);
        return c;
    }
}

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
    address public owner;

    /**
      * @dev The Ownable constructor sets the original `owner` of the contract to the sender
      * account.
      */
    function Ownable() public {
        owner = msg.sender;
    }

    /**
      * @dev Throws if called by any account other than the owner.
      */
    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    /**
    * @dev Allows the current owner to transfer control of the contract to a newOwner.
    * @param newOwner The address to transfer ownership to.
    */
    function transferOwnership(address newOwner) public onlyOwner {
        if (newOwner != address(0)) {
            owner = newOwner;
        }
    }

}

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20Basic {
    uint public _totalSupply;
    function totalSupply() public constant returns (uint);
    function balanceOf(address who) public constant returns (uint);
    function transfer(address to, uint value) public;
    event Transfer(address indexed from, address indexed to, uint value);
}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
    function allowance(address owner, address spender) public constant returns (uint);
    function transferFrom(address from, address to, uint value) public;
    function approve(address spender, uint value) public;
    event Approval(address indexed owner, address indexed spender, uint value);
}

/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is Ownable, ERC20Basic {
    using SafeMath for uint;

    mapping(address => uint) public balances;

    // additional variables for use if transaction fees ever became necessary
    uint public basisPointsRate = 0;
    uint public maximumFee = 0;

    /**
    * @dev Fix for the ERC20 short address attack.
    */
    modifier onlyPayloadSize(uint size) {
        require(!(msg.data.length < size + 4));
        _;
    }

    /**
    * @dev transfer token for a specified address
    * @param _to The address to transfer to.
    * @param _value The amount to be transferred.
    */
    function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        uint sendAmount = _value.sub(fee);
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(msg.sender, owner, fee);
        }
        Transfer(msg.sender, _to, sendAmount);
    }

    /**
    * @dev Gets the balance of the specified address.
    * @param _owner The address to query the the balance of.
    * @return An uint representing the amount owned by the passed address.
    */
    function balanceOf(address _owner) public constant returns (uint balance) {
        return balances[_owner];
    }

}

/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is BasicToken, ERC20 {

    mapping (address => mapping (address => uint)) public allowed;

    uint public constant MAX_UINT = 2**256 - 1;

    /**
    * @dev Transfer tokens from one address to another
    * @param _from address The address which you want to send tokens from
    * @param _to address The address which you want to transfer to
    * @param _value uint the amount of tokens to be transferred
    */
    function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
        var _allowance = allowed[_from][msg.sender];

        // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
        // if (_value > _allowance) throw;

        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        if (_allowance < MAX_UINT) {
            allowed[_from][msg.sender] = _allowance.sub(_value);
        }
        uint sendAmount = _value.sub(fee);
        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(_from, owner, fee);
        }
        Transfer(_from, _to, sendAmount);
    }

    /**
    * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
    * @param _spender The address which will spend the funds.
    * @param _value The amount of tokens to be spent.
    */
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {

        // To change the approve amount you first have to reduce the addresses`
        //  allowance to zero by calling `approve(_spender, 0)` if it is not
        //  already 0 to mitigate the race condition described here:
        //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
        require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));

        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
    }

    /**
    * @dev Function to check the amount of tokens than an owner allowed to a spender.
    * @param _owner address The address which owns the funds.
    * @param _spender address The address which will spend the funds.
    * @return A uint specifying the amount of tokens still available for the spender.
    */
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        return allowed[_owner][_spender];
    }

}


/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() onlyOwner whenNotPaused public {
    paused = true;
    Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() onlyOwner whenPaused public {
    paused = false;
    Unpause();
  }
}

contract BlackList is Ownable, BasicToken {

    /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
    function getBlackListStatus(address _maker) external constant returns (bool) {
        return isBlackListed[_maker];
    }

    function getOwner() external constant returns (address) {
        return owner;
    }

    mapping (address => bool) public isBlackListed;
    
    function addBlackList (address _evilUser) public onlyOwner {
        isBlackListed[_evilUser] = true;
        AddedBlackList(_evilUser);
    }

    function removeBlackList (address _clearedUser) public onlyOwner {
        isBlackListed[_clearedUser] = false;
        RemovedBlackList(_clearedUser);
    }

    function destroyBlackFunds (address _blackListedUser) public onlyOwner {
        require(isBlackListed[_blackListedUser]);
        uint dirtyFunds = balanceOf(_blackListedUser);
        balances[_blackListedUser] = 0;
        _totalSupply -= dirtyFunds;
        DestroyedBlackFunds(_blackListedUser, dirtyFunds);
    }

    event DestroyedBlackFunds(address _blackListedUser, uint _balance);

    event AddedBlackList(address _user);

    event RemovedBlackList(address _user);

}

contract UpgradedStandardToken is StandardToken{
    // those methods are called by the legacy contract
    // and they must ensure msg.sender to be the contract address
    function transferByLegacy(address from, address to, uint value) public;
    function transferFromByLegacy(address sender, address from, address spender, uint value) public;
    function approveByLegacy(address from, address spender, uint value) public;
}

contract TetherToken is Pausable, StandardToken, BlackList {

    string public name;
    string public symbol;
    uint public decimals;
    address public upgradedAddress;
    bool public deprecated;

    //  The contract can be initialized with a number of tokens
    //  All the tokens are deposited to the owner address
    //
    // @param _balance Initial supply of the contract
    // @param _name Token Name
    // @param _symbol Token symbol
    // @param _decimals Token decimals
    function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
        _totalSupply = _initialSupply;
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        balances[owner] = _initialSupply;
        deprecated = false;
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transfer(address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[msg.sender]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
        } else {
            return super.transfer(_to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[_from]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
        } else {
            return super.transferFrom(_from, _to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function balanceOf(address who) public constant returns (uint) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).balanceOf(who);
        } else {
            return super.balanceOf(who);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
        } else {
            return super.approve(_spender, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        if (deprecated) {
            return StandardToken(upgradedAddress).allowance(_owner, _spender);
        } else {
            return super.allowance(_owner, _spender);
        }
    }

    // deprecate current contract in favour of a new one
    function deprecate(address _upgradedAddress) public onlyOwner {
        deprecated = true;
        upgradedAddress = _upgradedAddress;
        Deprecate(_upgradedAddress);
    }

    // deprecate current contract if favour of a new one
    function totalSupply() public constant returns (uint) {
        if (deprecated) {
            return StandardToken(upgradedAddress).totalSupply();
        } else {
            return _totalSupply;
        }
    }

    // Issue a new amount of tokens
    // these tokens are deposited into the owner address
    //
    // @param _amount Number of tokens to be issued
    function issue(uint amount) public onlyOwner {
        require(_totalSupply + amount > _totalSupply);
        require(balances[owner] + amount > balances[owner]);

        balances[owner] += amount;
        _totalSupply += amount;
        Issue(amount);
    }

    // Redeem tokens.
    // These tokens are withdrawn from the owner address
    // if the balance must be enough to cover the redeem
    // or the call will fail.
    // @param _amount Number of tokens to be issued
    function redeem(uint amount) public onlyOwner {
        require(_totalSupply >= amount);
        require(balances[owner] >= amount);

        _totalSupply -= amount;
        balances[owner] -= amount;
        Redeem(amount);
    }

    function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
        // Ensure transparency by hardcoding limit beyond which fees can never be added
        require(newBasisPoints < 20);
        require(newMaxFee < 50);

        basisPointsRate = newBasisPoints;
        maximumFee = newMaxFee.mul(10**decimals);

        Params(basisPointsRate, maximumFee);
    }

    // Called when new token are issued
    event Issue(uint amount);

    // Called when tokens are redeemed
    event Redeem(uint amount);

    // Called when contract is deprecated
    event Deprecate(address newAddress);

    // Called if contract ever adds fees
    event Params(uint feeBasisPoints, uint maxFee);
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity 0.8.4;
import {ISplitMain} from './interfaces/ISplitMain.sol';
import {ERC20} from '@rari-capital/solmate/src/tokens/ERC20.sol';
import {SafeTransferLib} from '@rari-capital/solmate/src/utils/SafeTransferLib.sol';
/**
 * ERRORS
 */
/// @notice Unauthorized sender
error Unauthorized();
/**
 * @title SplitWallet
 * @author 0xSplits <[email protected]>
 * @notice The implementation logic for `SplitProxy`.
 * @dev `SplitProxy` handles `receive()` itself to avoid the gas cost with `DELEGATECALL`.
 */
contract SplitWallet {
  using SafeTransferLib for address;
  using SafeTransferLib for ERC20;
  /**
   * EVENTS
   */
  /** @notice emitted after each successful ETH transfer to proxy
   *  @param split Address of the split that received ETH
   *  @param amount Amount of ETH received
   */
  event ReceiveETH(address indexed split, uint256 amount);
  /**
   * STORAGE
   */
  /**
   * STORAGE - CONSTANTS & IMMUTABLES
   */
  /// @notice address of SplitMain for split distributions & EOA/SC withdrawals
  ISplitMain public immutable splitMain;
  /**
   * MODIFIERS
   */
  /// @notice Reverts if the sender isn't SplitMain
  modifier onlySplitMain() {
    if (msg.sender != address(splitMain)) revert Unauthorized();
    _;
  }
  /**
   * CONSTRUCTOR
   */
  constructor() {
    splitMain = ISplitMain(msg.sender);
  }
  /**
   * FUNCTIONS - PUBLIC & EXTERNAL
   */
  /** @notice Sends amount `amount` of ETH in proxy to SplitMain
   *  @dev payable reduces gas cost; no vulnerability to accidentally lock
   *  ETH introduced since fn call is restricted to SplitMain
   *  @param amount Amount to send
   */
  function sendETHToMain(uint256 amount) external payable onlySplitMain() {
    address(splitMain).safeTransferETH(amount);
  }
  /** @notice Sends amount `amount` of ERC20 `token` in proxy to SplitMain
   *  @dev payable reduces gas cost; no vulnerability to accidentally lock
   *  ETH introduced since fn call is restricted to SplitMain
   *  @param token Token to send
   *  @param amount Amount to send
   */
  function sendERC20ToMain(ERC20 token, uint256 amount)
    external
    payable
    onlySplitMain()
  {
    token.safeTransfer(address(splitMain), amount);
  }
}
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity 0.8.4;
import {ERC20} from '@rari-capital/solmate/src/tokens/ERC20.sol';
/**
 * @title ISplitMain
 * @author 0xSplits <[email protected]>
 */
interface ISplitMain {
  /**
   * FUNCTIONS
   */
  function walletImplementation() external returns (address);
  function createSplit(
    address[] calldata accounts,
    uint32[] calldata percentAllocations,
    uint32 distributorFee,
    address controller
  ) external returns (address);
  function predictImmutableSplitAddress(
    address[] calldata accounts,
    uint32[] calldata percentAllocations,
    uint32 distributorFee
  ) external view returns (address);
  function updateSplit(
    address split,
    address[] calldata accounts,
    uint32[] calldata percentAllocations,
    uint32 distributorFee
  ) external;
  function transferControl(address split, address newController) external;
  function cancelControlTransfer(address split) external;
  function acceptControl(address split) external;
  function makeSplitImmutable(address split) external;
  function distributeETH(
    address split,
    address[] calldata accounts,
    uint32[] calldata percentAllocations,
    uint32 distributorFee,
    address distributorAddress
  ) external;
  function updateAndDistributeETH(
    address split,
    address[] calldata accounts,
    uint32[] calldata percentAllocations,
    uint32 distributorFee,
    address distributorAddress
  ) external;
  function distributeERC20(
    address split,
    ERC20 token,
    address[] calldata accounts,
    uint32[] calldata percentAllocations,
    uint32 distributorFee,
    address distributorAddress
  ) external;
  function updateAndDistributeERC20(
    address split,
    ERC20 token,
    address[] calldata accounts,
    uint32[] calldata percentAllocations,
    uint32 distributorFee,
    address distributorAddress
  ) external;
  function withdraw(
    address account,
    uint256 withdrawETH,
    ERC20[] calldata tokens
  ) external;
  /**
   * EVENTS
   */
  /** @notice emitted after each successful split creation
   *  @param split Address of the created split
   */
  event CreateSplit(address indexed split);
  /** @notice emitted after each successful split update
   *  @param split Address of the updated split
   */
  event UpdateSplit(address indexed split);
  /** @notice emitted after each initiated split control transfer
   *  @param split Address of the split control transfer was initiated for
   *  @param newPotentialController Address of the split's new potential controller
   */
  event InitiateControlTransfer(
    address indexed split,
    address indexed newPotentialController
  );
  /** @notice emitted after each canceled split control transfer
   *  @param split Address of the split control transfer was canceled for
   */
  event CancelControlTransfer(address indexed split);
  /** @notice emitted after each successful split control transfer
   *  @param split Address of the split control was transferred for
   *  @param previousController Address of the split's previous controller
   *  @param newController Address of the split's new controller
   */
  event ControlTransfer(
    address indexed split,
    address indexed previousController,
    address indexed newController
  );
  /** @notice emitted after each successful ETH balance split
   *  @param split Address of the split that distributed its balance
   *  @param amount Amount of ETH distributed
   *  @param distributorAddress Address to credit distributor fee to
   */
  event DistributeETH(
    address indexed split,
    uint256 amount,
    address indexed distributorAddress
  );
  /** @notice emitted after each successful ERC20 balance split
   *  @param split Address of the split that distributed its balance
   *  @param token Address of ERC20 distributed
   *  @param amount Amount of ERC20 distributed
   *  @param distributorAddress Address to credit distributor fee to
   */
  event DistributeERC20(
    address indexed split,
    ERC20 indexed token,
    uint256 amount,
    address indexed distributorAddress
  );
  /** @notice emitted after each successful withdrawal
   *  @param account Address that funds were withdrawn to
   *  @param ethAmount Amount of ETH withdrawn
   *  @param tokens Addresses of ERC20s withdrawn
   *  @param tokenAmounts Amounts of corresponding ERC20s withdrawn
   */
  event Withdrawal(
    address indexed account,
    uint256 ethAmount,
    ERC20[] tokens,
    uint256[] tokenAmounts
  );
}
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;
/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/Rari-Capital/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*///////////////////////////////////////////////////////////////
                                  EVENTS
    //////////////////////////////////////////////////////////////*/
    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
    /*///////////////////////////////////////////////////////////////
                             METADATA STORAGE
    //////////////////////////////////////////////////////////////*/
    string public name;
    string public symbol;
    uint8 public immutable decimals;
    /*///////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/
    uint256 public totalSupply;
    mapping(address => uint256) public balanceOf;
    mapping(address => mapping(address => uint256)) public allowance;
    /*///////////////////////////////////////////////////////////////
                             EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/
    bytes32 public constant PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    uint256 internal immutable INITIAL_CHAIN_ID;
    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
    mapping(address => uint256) public nonces;
    /*///////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/
    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals
    ) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }
    /*///////////////////////////////////////////////////////////////
                              ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/
    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }
    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;
        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }
        emit Transfer(msg.sender, to, amount);
        return true;
    }
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.
        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;
        balanceOf[from] -= amount;
        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }
        emit Transfer(from, to, amount);
        return true;
    }
    /*///////////////////////////////////////////////////////////////
                              EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");
        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            bytes32 digest = keccak256(
                abi.encodePacked(
                    "\\x19\\x01",
                    DOMAIN_SEPARATOR(),
                    keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
                )
            );
            address recoveredAddress = ecrecover(digest, v, r, s);
            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");
            allowance[recoveredAddress][spender] = value;
        }
        emit Approval(owner, spender, value);
    }
    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }
    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }
    /*///////////////////////////////////////////////////////////////
                       INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/
    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;
        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }
        emit Transfer(address(0), to, amount);
    }
    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;
        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }
        emit Transfer(from, address(0), amount);
    }
}
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;
import {ERC20} from "../tokens/ERC20.sol";
/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/Rari-Capital/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @author Modified from Gnosis (https://github.com/gnosis/gp-v2-contracts/blob/main/src/contracts/libraries/GPv2SafeERC20.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
library SafeTransferLib {
    /*///////////////////////////////////////////////////////////////
                            ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/
    function safeTransferETH(address to, uint256 amount) internal {
        bool callStatus;
        assembly {
            // Transfer the ETH and store if it succeeded or not.
            callStatus := call(gas(), to, amount, 0, 0, 0, 0)
        }
        require(callStatus, "ETH_TRANSFER_FAILED");
    }
    /*///////////////////////////////////////////////////////////////
                           ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/
    function safeTransferFrom(
        ERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        bool callStatus;
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata to memory piece by piece:
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000) // Begin with the function selector.
            mstore(add(freeMemoryPointer, 4), and(from, 0xffffffffffffffffffffffffffffffffffffffff)) // Mask and append the "from" argument.
            mstore(add(freeMemoryPointer, 36), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Mask and append the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Finally append the "amount" argument. No mask as it's a full 32 byte value.
            // Call the token and store if it succeeded or not.
            // We use 100 because the calldata length is 4 + 32 * 3.
            callStatus := call(gas(), token, 0, freeMemoryPointer, 100, 0, 0)
        }
        require(didLastOptionalReturnCallSucceed(callStatus), "TRANSFER_FROM_FAILED");
    }
    function safeTransfer(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool callStatus;
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata to memory piece by piece:
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000) // Begin with the function selector.
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Mask and append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Finally append the "amount" argument. No mask as it's a full 32 byte value.
            // Call the token and store if it succeeded or not.
            // We use 68 because the calldata length is 4 + 32 * 2.
            callStatus := call(gas(), token, 0, freeMemoryPointer, 68, 0, 0)
        }
        require(didLastOptionalReturnCallSucceed(callStatus), "TRANSFER_FAILED");
    }
    function safeApprove(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool callStatus;
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata to memory piece by piece:
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000) // Begin with the function selector.
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Mask and append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Finally append the "amount" argument. No mask as it's a full 32 byte value.
            // Call the token and store if it succeeded or not.
            // We use 68 because the calldata length is 4 + 32 * 2.
            callStatus := call(gas(), token, 0, freeMemoryPointer, 68, 0, 0)
        }
        require(didLastOptionalReturnCallSucceed(callStatus), "APPROVE_FAILED");
    }
    /*///////////////////////////////////////////////////////////////
                         INTERNAL HELPER LOGIC
    //////////////////////////////////////////////////////////////*/
    function didLastOptionalReturnCallSucceed(bool callStatus) private pure returns (bool success) {
        assembly {
            // Get how many bytes the call returned.
            let returnDataSize := returndatasize()
            // If the call reverted:
            if iszero(callStatus) {
                // Copy the revert message into memory.
                returndatacopy(0, 0, returnDataSize)
                // Revert with the same message.
                revert(0, returnDataSize)
            }
            switch returnDataSize
            case 32 {
                // Copy the return data into memory.
                returndatacopy(0, 0, returnDataSize)
                // Set success to whether it returned true.
                success := iszero(iszero(mload(0)))
            }
            case 0 {
                // There was no return data.
                success := 1
            }
            default {
                // It returned some malformed input.
                success := 0
            }
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity 0.8.23;
interface ISwapERC20 {
  struct OrderERC20 {
    uint256 nonce; // Unique number per signatory per order
    uint256 expiry; // Expiry time (seconds since unix epoch)
    address signerWallet; // Party to the swap that sets terms
    address signerToken; // ERC20 token address transferred from signer
    uint256 signerAmount; // Amount of tokens transferred from signer
    address senderWallet; // Party to the swap that accepts terms
    address senderToken; // ERC20 token address transferred from sender
    uint256 senderAmount; // Amount of tokens transferred from sender
    uint8 v; // ECDSA
    bytes32 r;
    bytes32 s;
  }
  event SwapERC20(uint256 indexed nonce, address indexed signerWallet);
  event Cancel(uint256 indexed nonce, address indexed signerWallet);
  event Authorize(address indexed signer, address indexed signerWallet);
  event Revoke(address indexed signer, address indexed signerWallet);
  event SetProtocolFee(uint256 protocolFee);
  event SetProtocolFeeLight(uint256 protocolFeeLight);
  event SetProtocolFeeWallet(address indexed feeWallet);
  event SetBonusScale(uint256 bonusScale);
  event SetBonusMax(uint256 bonusMax);
  event SetStaking(address indexed staking);
  error ChainIdChanged();
  error InvalidFee();
  error InvalidFeeLight();
  error InvalidFeeWallet();
  error InvalidStaking();
  error OrderExpired();
  error MaxTooHigh();
  error NonceAlreadyUsed(uint256);
  error ScaleTooHigh();
  error SignatoryInvalid();
  error SignatureInvalid();
  error TransferFromFailed();
  function swap(
    address recipient,
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external;
  function swapAnySender(
    address recipient,
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external;
  function swapLight(
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external;
  function authorize(address sender) external;
  function revoke() external;
  function cancel(uint256[] calldata nonces) external;
  function check(
    address senderWallet,
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external view returns (bytes32[] memory);
  function nonceUsed(address, uint256) external view returns (bool);
  function authorized(address) external view returns (address);
  function calculateProtocolFee(
    address,
    uint256
  ) external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.23;
import { ECDSA } from "solady/src/utils/ECDSA.sol";
import { EIP712 } from "solady/src/utils/EIP712.sol";
import { ERC20 } from "solady/src/tokens/ERC20.sol";
import { Ownable } from "solady/src/auth/Ownable.sol";
import { SafeTransferLib } from "solady/src/utils/SafeTransferLib.sol";
import { SignatureCheckerLib } from "solady/src/utils/SignatureCheckerLib.sol";
import "./interfaces/ISwapERC20.sol";
/**
 * @title AirSwap: Atomic ERC20 Token Swap
 * @notice https://www.airswap.io/
 */
contract SwapERC20 is ISwapERC20, Ownable, EIP712 {
  uint256 public immutable DOMAIN_CHAIN_ID;
  bytes32 public immutable DOMAIN_SEPARATOR;
  bytes32 public constant ORDER_TYPEHASH =
    keccak256(
      abi.encodePacked(
        "OrderERC20(uint256 nonce,uint256 expiry,address signerWallet,address signerToken,uint256 signerAmount,",
        "uint256 protocolFee,address senderWallet,address senderToken,uint256 senderAmount)"
      )
    );
  uint256 public constant FEE_DIVISOR = 10000;
  uint256 private constant MAX_ERROR_COUNT = 8;
  uint256 private constant MAX_MAX = 100;
  uint256 private constant MAX_SCALE = 77;
  /**
   * @notice Double mapping of signers to nonce groups to nonce states
   * @dev The nonce group is computed as nonce / 256, so each group of 256 sequential nonces uses the same key
   * @dev The nonce states are encoded as 256 bits, for each nonce in the group 0 means available and 1 means used
   */
  mapping(address => mapping(uint256 => uint256)) private _nonceGroups;
  // Mapping of signer to authorized signatory
  mapping(address => address) public override authorized;
  uint256 public protocolFee;
  uint256 public protocolFeeLight;
  address public protocolFeeWallet;
  uint256 public bonusScale;
  uint256 public bonusMax;
  address public stakingToken;
  /**
   * @notice SwapERC20 constructor
   * @dev Sets domain and version for EIP712 signatures
   * @param _protocolFee uin256 protocol fee to be assessed on swaps
   * @param _protocolFeeWallet address destination for protocol fees
   * @param _bonusScale uin256 scale factor for bonus
   * @param _bonusMax uint256 max bonus percentage
   */
  constructor(
    uint256 _protocolFee,
    uint256 _protocolFeeLight,
    address _protocolFeeWallet,
    uint256 _bonusScale,
    uint256 _bonusMax
  ) {
    if (_protocolFee >= FEE_DIVISOR) revert InvalidFee();
    if (_protocolFeeLight >= FEE_DIVISOR) revert InvalidFeeLight();
    if (_protocolFeeWallet == address(0)) revert InvalidFeeWallet();
    if (_bonusMax > MAX_MAX) revert MaxTooHigh();
    if (_bonusScale > MAX_SCALE) revert ScaleTooHigh();
    _initializeOwner(msg.sender);
    DOMAIN_CHAIN_ID = block.chainid;
    DOMAIN_SEPARATOR = _domainSeparator();
    protocolFee = _protocolFee;
    protocolFeeLight = _protocolFeeLight;
    protocolFeeWallet = _protocolFeeWallet;
    bonusMax = _bonusMax;
    bonusScale = _bonusScale;
  }
  /**
   * @notice Return EIP712 domain values
   * @return name EIP712 domain name
   * @return version EIP712 domain version
   */
  function _domainNameAndVersion()
    internal
    pure
    override
    returns (string memory name, string memory version)
  {
    name = "SWAP_ERC20";
    version = "4.3";
  }
  /**
   * @notice Atomic ERC20 Swap
   * @param recipient address Wallet to receive sender proceeds
   * @param nonce uint256 Unique and should be sequential
   * @param expiry uint256 Expiry in seconds since 1 January 1970
   * @param signerWallet address Wallet of the signer
   * @param signerToken address ERC20 token transferred from the signer
   * @param signerAmount uint256 Amount transferred from the signer
   * @param senderToken address ERC20 token transferred from the sender
   * @param senderAmount uint256 Amount transferred from the sender
   * @param v uint8 "v" value of the ECDSA signature
   * @param r bytes32 "r" value of the ECDSA signature
   * @param s bytes32 "s" value of the ECDSA signature
   */
  function swap(
    address recipient,
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external override {
    // Ensure the order is valid
    _check(
      nonce,
      expiry,
      signerWallet,
      signerToken,
      signerAmount,
      msg.sender,
      senderToken,
      senderAmount,
      v,
      r,
      s
    );
    // Transfer token from sender to signer
    SafeTransferLib.safeTransferFrom(
      senderToken,
      msg.sender,
      signerWallet,
      senderAmount
    );
    // Transfer token from signer to recipient
    SafeTransferLib.safeTransferFrom(
      signerToken,
      signerWallet,
      recipient,
      signerAmount
    );
    // Calculate and transfer protocol fee
    _transferProtocolFee(signerToken, signerWallet, signerAmount);
    // Emit event
    emit SwapERC20(nonce, signerWallet);
  }
  /**
   * @notice Atomic ERC20 Swap for Any Sender
   * @param recipient address Wallet to receive sender proceeds
   * @param nonce uint256 Unique and should be sequential
   * @param expiry uint256 Expiry in seconds since 1 January 1970
   * @param signerWallet address Wallet of the signer
   * @param signerToken address ERC20 token transferred from the signer
   * @param signerAmount uint256 Amount transferred from the signer
   * @param senderToken address ERC20 token transferred from the sender
   * @param senderAmount uint256 Amount transferred from the sender
   * @param v uint8 "v" value of the ECDSA signature
   * @param r bytes32 "r" value of the ECDSA signature
   * @param s bytes32 "s" value of the ECDSA signature
   */
  function swapAnySender(
    address recipient,
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external override {
    // Ensure the order is valid
    _check(
      nonce,
      expiry,
      signerWallet,
      signerToken,
      signerAmount,
      address(0),
      senderToken,
      senderAmount,
      v,
      r,
      s
    );
    // Transfer token from sender to signer
    SafeTransferLib.safeTransferFrom(
      senderToken,
      msg.sender,
      signerWallet,
      senderAmount
    );
    // Transfer token from signer to recipient
    SafeTransferLib.safeTransferFrom(
      signerToken,
      signerWallet,
      recipient,
      signerAmount
    );
    // Calculate and transfer protocol fee
    _transferProtocolFee(signerToken, signerWallet, signerAmount);
    // Emit event
    emit SwapERC20(nonce, signerWallet);
  }
  /**
   * @notice Swap Atomic ERC20 Swap (Minimal Gas)
   * @dev No transfer checks. Only use with known tokens.
   * @param nonce uint256 Unique and should be sequential
   * @param expiry uint256 Expiry in seconds since 1 January 1970
   * @param signerWallet address Wallet of the signer
   * @param signerToken address ERC20 token transferred from the signer
   * @param signerAmount uint256 Amount transferred from the signer
   * @param senderToken address ERC20 token transferred from the sender
   * @param senderAmount uint256 Amount transferred from the sender
   * @param v uint8 "v" value of the ECDSA signature
   * @param r bytes32 "r" value of the ECDSA signature
   * @param s bytes32 "s" value of the ECDSA signature
   */
  function swapLight(
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external override {
    // Ensure the expiry is not passed
    if (expiry <= block.timestamp) revert OrderExpired();
    // Recover the signatory from the hash and signature
    address signatory = ECDSA.tryRecover(
      keccak256(
        abi.encodePacked(
          "\\x19\\x01", // EIP191: Indicates EIP712
          DOMAIN_SEPARATOR,
          keccak256(
            abi.encode(
              ORDER_TYPEHASH,
              nonce,
              expiry,
              signerWallet,
              signerToken,
              signerAmount,
              protocolFeeLight,
              msg.sender,
              senderToken,
              senderAmount
            )
          )
        )
      ),
      v,
      r,
      s
    );
    // Ensure the signatory is not null
    if (signatory == address(0)) revert SignatureInvalid();
    // Ensure the nonce is not yet used and if not mark it used
    if (!_markNonceAsUsed(signatory, nonce)) revert NonceAlreadyUsed(nonce);
    // Ensure signatory is authorized to sign
    if (authorized[signerWallet] != address(0)) {
      // If one is set by signer wallet, signatory must be authorized
      if (signatory != authorized[signerWallet]) revert SignatureInvalid();
    } else {
      // Otherwise, signatory must be signer wallet
      if (signatory != signerWallet) revert SignatureInvalid();
    }
    // Transfer token from sender to signer
    SafeTransferLib.safeTransferFrom(
      senderToken,
      msg.sender,
      signerWallet,
      senderAmount
    );
    // Transfer token from signer to sender
    SafeTransferLib.safeTransferFrom(
      signerToken,
      signerWallet,
      msg.sender,
      signerAmount
    );
    // Transfer protocol fee from signer to fee wallet
    SafeTransferLib.safeTransferFrom(
      signerToken,
      signerWallet,
      protocolFeeWallet,
      (signerAmount * protocolFeeLight) / FEE_DIVISOR
    );
    // Emit event
    emit SwapERC20(nonce, signerWallet);
  }
  /**
   * @notice Set the protocol fee
   * @param _protocolFee uint256 Value of the fee in basis points
   */
  function setProtocolFee(uint256 _protocolFee) external onlyOwner {
    // Ensure the fee is less than divisor
    if (_protocolFee >= FEE_DIVISOR) revert InvalidFee();
    protocolFee = _protocolFee;
    emit SetProtocolFee(_protocolFee);
  }
  /**
   * @notice Set the light protocol fee
   * @param _protocolFeeLight uint256 Value of the fee in basis points
   */
  function setProtocolFeeLight(uint256 _protocolFeeLight) external onlyOwner {
    // Ensure the fee is less than divisor
    if (_protocolFeeLight >= FEE_DIVISOR) revert InvalidFeeLight();
    protocolFeeLight = _protocolFeeLight;
    emit SetProtocolFeeLight(_protocolFeeLight);
  }
  /**
   * @notice Set the protocol fee wallet
   * @param _protocolFeeWallet address Wallet to transfer fee to
   */
  function setProtocolFeeWallet(address _protocolFeeWallet) external onlyOwner {
    // Ensure the new fee wallet is not null
    if (_protocolFeeWallet == address(0)) revert InvalidFeeWallet();
    protocolFeeWallet = _protocolFeeWallet;
    emit SetProtocolFeeWallet(_protocolFeeWallet);
  }
  /**
   * @notice Set staking bonus max
   * @dev Only owner
   * @param _bonusMax uint256
   */
  function setBonusMax(uint256 _bonusMax) external onlyOwner {
    if (_bonusMax > MAX_MAX) revert MaxTooHigh();
    bonusMax = _bonusMax;
    emit SetBonusMax(_bonusMax);
  }
  /**
   * @notice Set staking bonus scale
   * @dev Only owner
   * @param _bonusScale uint256
   */
  function setBonusScale(uint256 _bonusScale) external onlyOwner {
    if (_bonusScale > MAX_SCALE) revert ScaleTooHigh();
    bonusScale = _bonusScale;
    emit SetBonusScale(_bonusScale);
  }
  /**
   * @notice Set staking token
   * @param _stakingToken address Token to check balances on
   */
  function setStaking(address _stakingToken) external onlyOwner {
    // Ensure the new staking token is not null
    if (_stakingToken == address(0)) revert InvalidStaking();
    stakingToken = _stakingToken;
    emit SetStaking(_stakingToken);
  }
  /**
   * @notice Authorize a signatory
   * @param signatory address Wallet of the signatory to authorize
   * @dev Emits an Authorize event
   */
  function authorize(address signatory) external override {
    if (signatory == address(0)) revert SignatoryInvalid();
    authorized[msg.sender] = signatory;
    emit Authorize(signatory, msg.sender);
  }
  /**
   * @notice Revoke the signatory
   * @dev Emits a Revoke event
   */
  function revoke() external override {
    address tmp = authorized[msg.sender];
    delete authorized[msg.sender];
    emit Revoke(tmp, msg.sender);
  }
  /**
   * @notice Cancel one or more nonces
   * @dev Cancelled nonces are marked as used
   * @dev Emits a Cancel event
   * @dev Out of gas may occur in arrays of length > 400
   * @param nonces uint256[] List of nonces to cancel
   */
  function cancel(uint256[] calldata nonces) external override {
    for (uint256 i; i < nonces.length; ) {
      uint256 nonce = nonces[i];
      if (_markNonceAsUsed(msg.sender, nonce)) {
        emit Cancel(nonce, msg.sender);
      }
      unchecked {
        ++i;
      }
    }
  }
  /**
   * @notice Checks an order for errors
   * @param senderWallet address Wallet that would send the order
   * @param nonce uint256 Unique and should be sequential
   * @param expiry uint256 Expiry in seconds since 1 January 1970
   * @param signerWallet address Wallet of the signer
   * @param signerToken address ERC20 token transferred from the signer
   * @param signerAmount uint256 Amount transferred from the signer
   * @param senderToken address ERC20 token transferred from the sender
   * @param senderAmount uint256 Amount transferred from the sender
   * @param v uint8 "v" value of the ECDSA signature
   * @param r bytes32 "r" value of the ECDSA signature
   * @param s bytes32 "s" value of the ECDSA signature
   * @return bytes32[] errors
   */
  function check(
    address senderWallet,
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external view returns (bytes32[] memory) {
    bytes32[] memory errors = new bytes32[](MAX_ERROR_COUNT);
    uint256 count;
    OrderERC20 memory order;
    order.nonce = nonce;
    order.expiry = expiry;
    order.signerWallet = signerWallet;
    order.signerToken = signerToken;
    order.signerAmount = signerAmount;
    order.senderToken = senderToken;
    order.senderAmount = senderAmount;
    order.v = v;
    order.r = r;
    order.s = s;
    order.senderWallet = senderWallet;
    if (DOMAIN_CHAIN_ID != block.chainid) {
      errors[count++] = "ChainIdChanged";
    }
    // Validate as the authorized signatory if set
    address signatory = order.signerWallet;
    if (authorized[signatory] != address(0)) {
      signatory = authorized[signatory];
    }
    if (
      !SignatureCheckerLib.isValidSignatureNow(
        signatory,
        _getOrderHash(
          order.nonce,
          order.expiry,
          order.signerWallet,
          order.signerToken,
          order.signerAmount,
          order.senderWallet,
          order.senderToken,
          order.senderAmount
        ),
        abi.encodePacked(r, s, v)
      )
    ) {
      errors[count++] = "SignatureInvalid";
    } else if (nonceUsed(signatory, order.nonce)) {
      errors[count++] = "NonceAlreadyUsed";
    }
    if (order.expiry < block.timestamp) {
      errors[count++] = "OrderExpired";
    }
    if (order.senderWallet != address(0)) {
      uint256 senderBalance = ERC20(order.senderToken).balanceOf(
        order.senderWallet
      );
      uint256 senderAllowance = ERC20(order.senderToken).allowance(
        order.senderWallet,
        address(this)
      );
      if (senderAllowance < order.senderAmount) {
        errors[count++] = "SenderAllowanceLow";
      }
      if (senderBalance < order.senderAmount) {
        errors[count++] = "SenderBalanceLow";
      }
    }
    uint256 signerBalance = ERC20(order.signerToken).balanceOf(
      order.signerWallet
    );
    uint256 signerAllowance = ERC20(order.signerToken).allowance(
      order.signerWallet,
      address(this)
    );
    uint256 signerFeeAmount = (order.signerAmount * protocolFee) / FEE_DIVISOR;
    if (signerAllowance < order.signerAmount + signerFeeAmount) {
      errors[count++] = "SignerAllowanceLow";
    }
    if (signerBalance < order.signerAmount + signerFeeAmount) {
      errors[count++] = "SignerBalanceLow";
    }
    // Truncate errors array to actual count
    if (count != errors.length) {
      assembly {
        mstore(errors, count)
      }
    }
    return errors;
  }
  /**
   * @notice Calculates bonus from staking balance
   * @param stakingBalance uint256
   * @param feeAmount uint256
   */
  function calculateBonus(
    uint256 stakingBalance,
    uint256 feeAmount
  ) public view returns (uint256) {
    uint256 divisor = (uint256(10) ** bonusScale) + stakingBalance;
    return (bonusMax * stakingBalance * feeAmount) / divisor / MAX_MAX;
  }
  /**
   * @notice Calculates protocol fee for an account
   * @param wallet address
   * @param amount uint256
   */
  function calculateProtocolFee(
    address wallet,
    uint256 amount
  ) external view override returns (uint256) {
    // Transfer fee from signer to feeWallet
    uint256 feeAmount = (amount * protocolFee) / FEE_DIVISOR;
    if (stakingToken != address(0) && feeAmount > 0) {
      uint256 bonusAmount = calculateBonus(
        ERC20(stakingToken).balanceOf(wallet),
        feeAmount
      );
      return feeAmount - bonusAmount;
    }
    return feeAmount;
  }
  /**
   * @notice Returns true if the nonce has been used
   * @param signer address Address of the signer
   * @param nonce uint256 Nonce being checked
   */
  function nonceUsed(
    address signer,
    uint256 nonce
  ) public view override returns (bool) {
    uint256 groupKey = nonce / 256;
    uint256 indexInGroup = nonce % 256;
    return (_nonceGroups[signer][groupKey] >> indexInGroup) & 1 == 1;
  }
  /**
   * @notice Marks a nonce as used for the given signer
   * @param signer address Address of the signer for which to mark the nonce as used
   * @param nonce uint256 Nonce to be marked as used
   * @return bool True if the nonce was not marked as used already
   */
  function _markNonceAsUsed(
    address signer,
    uint256 nonce
  ) private returns (bool) {
    uint256 groupKey = nonce / 256;
    uint256 indexInGroup = nonce % 256;
    uint256 group = _nonceGroups[signer][groupKey];
    // If it is already used, return false
    if ((group >> indexInGroup) & 1 == 1) {
      return false;
    }
    _nonceGroups[signer][groupKey] = group | (uint256(1) << indexInGroup);
    return true;
  }
  /**
   * @notice Checks order and reverts on error
   * @param nonce uint256 Unique and should be sequential
   * @param expiry uint256 Expiry in seconds since 1 January 1970
   * @param signerWallet address Wallet of the signer
   * @param signerToken address ERC20 token transferred from the signer
   * @param signerAmount uint256 Amount transferred from the signer
   * @param senderToken address ERC20 token transferred from the sender
   * @param senderAmount uint256 Amount transferred from the sender
   * @param v uint8 "v" value of the ECDSA signature
   * @param r bytes32 "r" value of the ECDSA signature
   * @param s bytes32 "s" value of the ECDSA signature
   */
  function _check(
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderWallet,
    address senderToken,
    uint256 senderAmount,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) private {
    // Ensure execution on the intended chain
    if (DOMAIN_CHAIN_ID != block.chainid) revert ChainIdChanged();
    // Ensure the expiry is not passed
    if (expiry <= block.timestamp) revert OrderExpired();
    // Validate as the authorized signatory if set
    address signatory = signerWallet;
    if (authorized[signatory] != address(0)) {
      signatory = authorized[signatory];
    }
    // Ensure the signature is correct for the order
    if (
      !SignatureCheckerLib.isValidSignatureNow(
        signatory,
        _getOrderHash(
          nonce,
          expiry,
          signerWallet,
          signerToken,
          signerAmount,
          senderWallet,
          senderToken,
          senderAmount
        ),
        abi.encodePacked(r, s, v)
      )
    ) revert SignatureInvalid();
    // Ensure the nonce is not yet used and if not mark as used
    if (!_markNonceAsUsed(signatory, nonce)) revert NonceAlreadyUsed(nonce);
  }
  /**
   * @notice Hashes order parameters
   * @param nonce uint256
   * @param expiry uint256
   * @param signerWallet address
   * @param signerToken address
   * @param signerAmount uint256
   * @param senderToken address
   * @param senderAmount uint256
   * @return bytes32
   */
  function _getOrderHash(
    uint256 nonce,
    uint256 expiry,
    address signerWallet,
    address signerToken,
    uint256 signerAmount,
    address senderWallet,
    address senderToken,
    uint256 senderAmount
  ) private view returns (bytes32) {
    return
      keccak256(
        abi.encodePacked(
          "\\x19\\x01", // EIP191: Indicates EIP712
          DOMAIN_SEPARATOR,
          keccak256(
            abi.encode(
              ORDER_TYPEHASH,
              nonce,
              expiry,
              signerWallet,
              signerToken,
              signerAmount,
              protocolFee,
              senderWallet,
              senderToken,
              senderAmount
            )
          )
        )
      );
  }
  /**
   * @notice Calculates and transfers protocol fee and staking bonus
   * @param sourceToken address
   * @param sourceWallet address
   * @param amount uint256
   */
  function _transferProtocolFee(
    address sourceToken,
    address sourceWallet,
    uint256 amount
  ) private {
    // Determine protocol fee from amount
    uint256 feeAmount = (amount * protocolFee) / FEE_DIVISOR;
    if (feeAmount > 0) {
      uint256 bonusAmount;
      if (stakingToken != address(0)) {
        // Only check staking bonus if staking token set
        bonusAmount = calculateBonus(
          ERC20(stakingToken).balanceOf(msg.sender),
          feeAmount
        );
      }
      if (bonusAmount > 0) {
        // Transfer staking bonus from source to msg.sender
        SafeTransferLib.safeTransferFrom(
          sourceToken,
          sourceWallet,
          msg.sender,
          bonusAmount
        );
        // Transfer remaining protocol fee from source to fee wallet
        SafeTransferLib.safeTransferFrom(
          sourceToken,
          sourceWallet,
          protocolFeeWallet,
          feeAmount - bonusAmount
        );
      } else {
        // Transfer full protocol fee from source to fee wallet
        SafeTransferLib.safeTransferFrom(
          sourceToken,
          sourceWallet,
          protocolFeeWallet,
          feeAmount
        );
      }
    }
  }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;
/// @notice Simple single owner authorization mixin.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/auth/Ownable.sol)
///
/// @dev Note:
/// This implementation does NOT auto-initialize the owner to `msg.sender`.
/// You MUST call the `_initializeOwner` in the constructor / initializer.
///
/// While the ownable portion follows
/// [EIP-173](https://eips.ethereum.org/EIPS/eip-173) for compatibility,
/// the nomenclature for the 2-step ownership handover may be unique to this codebase.
abstract contract Ownable {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev The caller is not authorized to call the function.
    error Unauthorized();
    /// @dev The `newOwner` cannot be the zero address.
    error NewOwnerIsZeroAddress();
    /// @dev The `pendingOwner` does not have a valid handover request.
    error NoHandoverRequest();
    /// @dev Cannot double-initialize.
    error AlreadyInitialized();
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev The ownership is transferred from `oldOwner` to `newOwner`.
    /// This event is intentionally kept the same as OpenZeppelin's Ownable to be
    /// compatible with indexers and [EIP-173](https://eips.ethereum.org/EIPS/eip-173),
    /// despite it not being as lightweight as a single argument event.
    event OwnershipTransferred(address indexed oldOwner, address indexed newOwner);
    /// @dev An ownership handover to `pendingOwner` has been requested.
    event OwnershipHandoverRequested(address indexed pendingOwner);
    /// @dev The ownership handover to `pendingOwner` has been canceled.
    event OwnershipHandoverCanceled(address indexed pendingOwner);
    /// @dev `keccak256(bytes("OwnershipTransferred(address,address)"))`.
    uint256 private constant _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE =
        0x8be0079c531659141344cd1fd0a4f28419497f9722a3daafe3b4186f6b6457e0;
    /// @dev `keccak256(bytes("OwnershipHandoverRequested(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE =
        0xdbf36a107da19e49527a7176a1babf963b4b0ff8cde35ee35d6cd8f1f9ac7e1d;
    /// @dev `keccak256(bytes("OwnershipHandoverCanceled(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE =
        0xfa7b8eab7da67f412cc9575ed43464468f9bfbae89d1675917346ca6d8fe3c92;
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev The owner slot is given by:
    /// `bytes32(~uint256(uint32(bytes4(keccak256("_OWNER_SLOT_NOT")))))`.
    /// It is intentionally chosen to be a high value
    /// to avoid collision with lower slots.
    /// The choice of manual storage layout is to enable compatibility
    /// with both regular and upgradeable contracts.
    bytes32 internal constant _OWNER_SLOT =
        0xffffffffffffffffffffffffffffffffffffffffffffffffffffffff74873927;
    /// The ownership handover slot of `newOwner` is given by:
    /// ```
    ///     mstore(0x00, or(shl(96, user), _HANDOVER_SLOT_SEED))
    ///     let handoverSlot := keccak256(0x00, 0x20)
    /// ```
    /// It stores the expiry timestamp of the two-step ownership handover.
    uint256 private constant _HANDOVER_SLOT_SEED = 0x389a75e1;
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     INTERNAL FUNCTIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Override to return true to make `_initializeOwner` prevent double-initialization.
    function _guardInitializeOwner() internal pure virtual returns (bool guard) {}
    /// @dev Initializes the owner directly without authorization guard.
    /// This function must be called upon initialization,
    /// regardless of whether the contract is upgradeable or not.
    /// This is to enable generalization to both regular and upgradeable contracts,
    /// and to save gas in case the initial owner is not the caller.
    /// For performance reasons, this function will not check if there
    /// is an existing owner.
    function _initializeOwner(address newOwner) internal virtual {
        if (_guardInitializeOwner()) {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                if sload(ownerSlot) {
                    mstore(0x00, 0x0dc149f0) // `AlreadyInitialized()`.
                    revert(0x1c, 0x04)
                }
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Store the new value.
                sstore(ownerSlot, or(newOwner, shl(255, iszero(newOwner))))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
            }
        } else {
            /// @solidity memory-safe-assembly
            assembly {
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Store the new value.
                sstore(_OWNER_SLOT, newOwner)
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
            }
        }
    }
    /// @dev Sets the owner directly without authorization guard.
    function _setOwner(address newOwner) internal virtual {
        if (_guardInitializeOwner()) {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
                // Store the new value.
                sstore(ownerSlot, or(newOwner, shl(255, iszero(newOwner))))
            }
        } else {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
                // Store the new value.
                sstore(ownerSlot, newOwner)
            }
        }
    }
    /// @dev Throws if the sender is not the owner.
    function _checkOwner() internal view virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // If the caller is not the stored owner, revert.
            if iszero(eq(caller(), sload(_OWNER_SLOT))) {
                mstore(0x00, 0x82b42900) // `Unauthorized()`.
                revert(0x1c, 0x04)
            }
        }
    }
    /// @dev Returns how long a two-step ownership handover is valid for in seconds.
    /// Override to return a different value if needed.
    /// Made internal to conserve bytecode. Wrap it in a public function if needed.
    function _ownershipHandoverValidFor() internal view virtual returns (uint64) {
        return 48 * 3600;
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  PUBLIC UPDATE FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Allows the owner to transfer the ownership to `newOwner`.
    function transferOwnership(address newOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(shl(96, newOwner)) {
                mstore(0x00, 0x7448fbae) // `NewOwnerIsZeroAddress()`.
                revert(0x1c, 0x04)
            }
        }
        _setOwner(newOwner);
    }
    /// @dev Allows the owner to renounce their ownership.
    function renounceOwnership() public payable virtual onlyOwner {
        _setOwner(address(0));
    }
    /// @dev Request a two-step ownership handover to the caller.
    /// The request will automatically expire in 48 hours (172800 seconds) by default.
    function requestOwnershipHandover() public payable virtual {
        unchecked {
            uint256 expires = block.timestamp + _ownershipHandoverValidFor();
            /// @solidity memory-safe-assembly
            assembly {
                // Compute and set the handover slot to `expires`.
                mstore(0x0c, _HANDOVER_SLOT_SEED)
                mstore(0x00, caller())
                sstore(keccak256(0x0c, 0x20), expires)
                // Emit the {OwnershipHandoverRequested} event.
                log2(0, 0, _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE, caller())
            }
        }
    }
    /// @dev Cancels the two-step ownership handover to the caller, if any.
    function cancelOwnershipHandover() public payable virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x20), 0)
            // Emit the {OwnershipHandoverCanceled} event.
            log2(0, 0, _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE, caller())
        }
    }
    /// @dev Allows the owner to complete the two-step ownership handover to `pendingOwner`.
    /// Reverts if there is no existing ownership handover requested by `pendingOwner`.
    function completeOwnershipHandover(address pendingOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            let handoverSlot := keccak256(0x0c, 0x20)
            // If the handover does not exist, or has expired.
            if gt(timestamp(), sload(handoverSlot)) {
                mstore(0x00, 0x6f5e8818) // `NoHandoverRequest()`.
                revert(0x1c, 0x04)
            }
            // Set the handover slot to 0.
            sstore(handoverSlot, 0)
        }
        _setOwner(pendingOwner);
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   PUBLIC READ FUNCTIONS                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns the owner of the contract.
    function owner() public view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := sload(_OWNER_SLOT)
        }
    }
    /// @dev Returns the expiry timestamp for the two-step ownership handover to `pendingOwner`.
    function ownershipHandoverExpiresAt(address pendingOwner)
        public
        view
        virtual
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the handover slot.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            // Load the handover slot.
            result := sload(keccak256(0x0c, 0x20))
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         MODIFIERS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Marks a function as only callable by the owner.
    modifier onlyOwner() virtual {
        _checkOwner();
        _;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;
/// @notice Simple ERC20 + EIP-2612 implementation.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/ERC20.sol)
///
/// @dev Note:
/// - The ERC20 standard allows minting and transferring to and from the zero address,
///   minting and transferring zero tokens, as well as self-approvals.
///   For performance, this implementation WILL NOT revert for such actions.
///   Please add any checks with overrides if desired.
/// - The `permit` function uses the ecrecover precompile (0x1).
///
/// If you are overriding:
/// - NEVER violate the ERC20 invariant:
///   the total sum of all balances must be equal to `totalSupply()`.
/// - Check that the overridden function is actually used in the function you want to
///   change the behavior of. Much of the code has been manually inlined for performance.
abstract contract ERC20 {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev The total supply has overflowed.
    error TotalSupplyOverflow();
    /// @dev The allowance has overflowed.
    error AllowanceOverflow();
    /// @dev The allowance has underflowed.
    error AllowanceUnderflow();
    /// @dev Insufficient balance.
    error InsufficientBalance();
    /// @dev Insufficient allowance.
    error InsufficientAllowance();
    /// @dev The permit is invalid.
    error InvalidPermit();
    /// @dev The permit has expired.
    error PermitExpired();
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Emitted when `amount` tokens is transferred from `from` to `to`.
    event Transfer(address indexed from, address indexed to, uint256 amount);
    /// @dev Emitted when `amount` tokens is approved by `owner` to be used by `spender`.
    event Approval(address indexed owner, address indexed spender, uint256 amount);
    /// @dev `keccak256(bytes("Transfer(address,address,uint256)"))`.
    uint256 private constant _TRANSFER_EVENT_SIGNATURE =
        0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;
    /// @dev `keccak256(bytes("Approval(address,address,uint256)"))`.
    uint256 private constant _APPROVAL_EVENT_SIGNATURE =
        0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925;
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev The storage slot for the total supply.
    uint256 private constant _TOTAL_SUPPLY_SLOT = 0x05345cdf77eb68f44c;
    /// @dev The balance slot of `owner` is given by:
    /// ```
    ///     mstore(0x0c, _BALANCE_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let balanceSlot := keccak256(0x0c, 0x20)
    /// ```
    uint256 private constant _BALANCE_SLOT_SEED = 0x87a211a2;
    /// @dev The allowance slot of (`owner`, `spender`) is given by:
    /// ```
    ///     mstore(0x20, spender)
    ///     mstore(0x0c, _ALLOWANCE_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let allowanceSlot := keccak256(0x0c, 0x34)
    /// ```
    uint256 private constant _ALLOWANCE_SLOT_SEED = 0x7f5e9f20;
    /// @dev The nonce slot of `owner` is given by:
    /// ```
    ///     mstore(0x0c, _NONCES_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let nonceSlot := keccak256(0x0c, 0x20)
    /// ```
    uint256 private constant _NONCES_SLOT_SEED = 0x38377508;
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev `(_NONCES_SLOT_SEED << 16) | 0x1901`.
    uint256 private constant _NONCES_SLOT_SEED_WITH_SIGNATURE_PREFIX = 0x383775081901;
    /// @dev `keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")`.
    bytes32 private constant _DOMAIN_TYPEHASH =
        0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f;
    /// @dev `keccak256("1")`.
    bytes32 private constant _VERSION_HASH =
        0xc89efdaa54c0f20c7adf612882df0950f5a951637e0307cdcb4c672f298b8bc6;
    /// @dev `keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")`.
    bytes32 private constant _PERMIT_TYPEHASH =
        0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       ERC20 METADATA                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns the name of the token.
    function name() public view virtual returns (string memory);
    /// @dev Returns the symbol of the token.
    function symbol() public view virtual returns (string memory);
    /// @dev Returns the decimals places of the token.
    function decimals() public view virtual returns (uint8) {
        return 18;
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           ERC20                            */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns the amount of tokens in existence.
    function totalSupply() public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := sload(_TOTAL_SUPPLY_SLOT)
        }
    }
    /// @dev Returns the amount of tokens owned by `owner`.
    function balanceOf(address owner) public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x20))
        }
    }
    /// @dev Returns the amount of tokens that `spender` can spend on behalf of `owner`.
    function allowance(address owner, address spender)
        public
        view
        virtual
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x34))
        }
    }
    /// @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
    ///
    /// Emits a {Approval} event.
    function approve(address spender, uint256 amount) public virtual returns (bool) {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the allowance slot and store the amount.
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x34), amount)
            // Emit the {Approval} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _APPROVAL_EVENT_SIGNATURE, caller(), shr(96, mload(0x2c)))
        }
        return true;
    }
    /// @dev Transfer `amount` tokens from the caller to `to`.
    ///
    /// Requirements:
    /// - `from` must at least have `amount`.
    ///
    /// Emits a {Transfer} event.
    function transfer(address to, uint256 amount) public virtual returns (bool) {
        _beforeTokenTransfer(msg.sender, to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the balance slot and load its value.
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, caller())
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Compute the balance slot of `to`.
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance of `to`.
            // Will not overflow because the sum of all user balances
            // cannot exceed the maximum uint256 value.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, caller(), shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(msg.sender, to, amount);
        return true;
    }
    /// @dev Transfers `amount` tokens from `from` to `to`.
    ///
    /// Note: Does not update the allowance if it is the maximum uint256 value.
    ///
    /// Requirements:
    /// - `from` must at least have `amount`.
    /// - The caller must have at least `amount` of allowance to transfer the tokens of `from`.
    ///
    /// Emits a {Transfer} event.
    function transferFrom(address from, address to, uint256 amount) public virtual returns (bool) {
        _beforeTokenTransfer(from, to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            let from_ := shl(96, from)
            // Compute the allowance slot and load its value.
            mstore(0x20, caller())
            mstore(0x0c, or(from_, _ALLOWANCE_SLOT_SEED))
            let allowanceSlot := keccak256(0x0c, 0x34)
            let allowance_ := sload(allowanceSlot)
            // If the allowance is not the maximum uint256 value.
            if add(allowance_, 1) {
                // Revert if the amount to be transferred exceeds the allowance.
                if gt(amount, allowance_) {
                    mstore(0x00, 0x13be252b) // `InsufficientAllowance()`.
                    revert(0x1c, 0x04)
                }
                // Subtract and store the updated allowance.
                sstore(allowanceSlot, sub(allowance_, amount))
            }
            // Compute the balance slot and load its value.
            mstore(0x0c, or(from_, _BALANCE_SLOT_SEED))
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Compute the balance slot of `to`.
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance of `to`.
            // Will not overflow because the sum of all user balances
            // cannot exceed the maximum uint256 value.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, shr(96, from_), shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(from, to, amount);
        return true;
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          EIP-2612                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev For more performance, override to return the constant value
    /// of `keccak256(bytes(name()))` if `name()` will never change.
    function _constantNameHash() internal view virtual returns (bytes32 result) {}
    /// @dev Returns the current nonce for `owner`.
    /// This value is used to compute the signature for EIP-2612 permit.
    function nonces(address owner) public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the nonce slot and load its value.
            mstore(0x0c, _NONCES_SLOT_SEED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x20))
        }
    }
    /// @dev Sets `value` as the allowance of `spender` over the tokens of `owner`,
    /// authorized by a signed approval by `owner`.
    ///
    /// Emits a {Approval} event.
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        bytes32 nameHash = _constantNameHash();
        //  We simply calculate it on-the-fly to allow for cases where the `name` may change.
        if (nameHash == bytes32(0)) nameHash = keccak256(bytes(name()));
        /// @solidity memory-safe-assembly
        assembly {
            // Revert if the block timestamp is greater than `deadline`.
            if gt(timestamp(), deadline) {
                mstore(0x00, 0x1a15a3cc) // `PermitExpired()`.
                revert(0x1c, 0x04)
            }
            let m := mload(0x40) // Grab the free memory pointer.
            // Clean the upper 96 bits.
            owner := shr(96, shl(96, owner))
            spender := shr(96, shl(96, spender))
            // Compute the nonce slot and load its value.
            mstore(0x0e, _NONCES_SLOT_SEED_WITH_SIGNATURE_PREFIX)
            mstore(0x00, owner)
            let nonceSlot := keccak256(0x0c, 0x20)
            let nonceValue := sload(nonceSlot)
            // Prepare the domain separator.
            mstore(m, _DOMAIN_TYPEHASH)
            mstore(add(m, 0x20), nameHash)
            mstore(add(m, 0x40), _VERSION_HASH)
            mstore(add(m, 0x60), chainid())
            mstore(add(m, 0x80), address())
            mstore(0x2e, keccak256(m, 0xa0))
            // Prepare the struct hash.
            mstore(m, _PERMIT_TYPEHASH)
            mstore(add(m, 0x20), owner)
            mstore(add(m, 0x40), spender)
            mstore(add(m, 0x60), value)
            mstore(add(m, 0x80), nonceValue)
            mstore(add(m, 0xa0), deadline)
            mstore(0x4e, keccak256(m, 0xc0))
            // Prepare the ecrecover calldata.
            mstore(0x00, keccak256(0x2c, 0x42))
            mstore(0x20, and(0xff, v))
            mstore(0x40, r)
            mstore(0x60, s)
            let t := staticcall(gas(), 1, 0, 0x80, 0x20, 0x20)
            // If the ecrecover fails, the returndatasize will be 0x00,
            // `owner` will be checked if it equals the hash at 0x00,
            // which evaluates to false (i.e. 0), and we will revert.
            // If the ecrecover succeeds, the returndatasize will be 0x20,
            // `owner` will be compared against the returned address at 0x20.
            if iszero(eq(mload(returndatasize()), owner)) {
                mstore(0x00, 0xddafbaef) // `InvalidPermit()`.
                revert(0x1c, 0x04)
            }
            // Increment and store the updated nonce.
            sstore(nonceSlot, add(nonceValue, t)) // `t` is 1 if ecrecover succeeds.
            // Compute the allowance slot and store the value.
            // The `owner` is already at slot 0x20.
            mstore(0x40, or(shl(160, _ALLOWANCE_SLOT_SEED), spender))
            sstore(keccak256(0x2c, 0x34), value)
            // Emit the {Approval} event.
            log3(add(m, 0x60), 0x20, _APPROVAL_EVENT_SIGNATURE, owner, spender)
            mstore(0x40, m) // Restore the free memory pointer.
            mstore(0x60, 0) // Restore the zero pointer.
        }
    }
    /// @dev Returns the EIP-712 domain separator for the EIP-2612 permit.
    function DOMAIN_SEPARATOR() public view virtual returns (bytes32 result) {
        bytes32 nameHash = _constantNameHash();
        //  We simply calculate it on-the-fly to allow for cases where the `name` may change.
        if (nameHash == bytes32(0)) nameHash = keccak256(bytes(name()));
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Grab the free memory pointer.
            mstore(m, _DOMAIN_TYPEHASH)
            mstore(add(m, 0x20), nameHash)
            mstore(add(m, 0x40), _VERSION_HASH)
            mstore(add(m, 0x60), chainid())
            mstore(add(m, 0x80), address())
            result := keccak256(m, 0xa0)
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL MINT FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Mints `amount` tokens to `to`, increasing the total supply.
    ///
    /// Emits a {Transfer} event.
    function _mint(address to, uint256 amount) internal virtual {
        _beforeTokenTransfer(address(0), to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            let totalSupplyBefore := sload(_TOTAL_SUPPLY_SLOT)
            let totalSupplyAfter := add(totalSupplyBefore, amount)
            // Revert if the total supply overflows.
            if lt(totalSupplyAfter, totalSupplyBefore) {
                mstore(0x00, 0xe5cfe957) // `TotalSupplyOverflow()`.
                revert(0x1c, 0x04)
            }
            // Store the updated total supply.
            sstore(_TOTAL_SUPPLY_SLOT, totalSupplyAfter)
            // Compute the balance slot and load its value.
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, 0, shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(address(0), to, amount);
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL BURN FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Burns `amount` tokens from `from`, reducing the total supply.
    ///
    /// Emits a {Transfer} event.
    function _burn(address from, uint256 amount) internal virtual {
        _beforeTokenTransfer(from, address(0), amount);
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the balance slot and load its value.
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, from)
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Subtract and store the updated total supply.
            sstore(_TOTAL_SUPPLY_SLOT, sub(sload(_TOTAL_SUPPLY_SLOT), amount))
            // Emit the {Transfer} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _TRANSFER_EVENT_SIGNATURE, shr(96, shl(96, from)), 0)
        }
        _afterTokenTransfer(from, address(0), amount);
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL TRANSFER FUNCTIONS                 */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Moves `amount` of tokens from `from` to `to`.
    function _transfer(address from, address to, uint256 amount) internal virtual {
        _beforeTokenTransfer(from, to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            let from_ := shl(96, from)
            // Compute the balance slot and load its value.
            mstore(0x0c, or(from_, _BALANCE_SLOT_SEED))
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Compute the balance slot of `to`.
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance of `to`.
            // Will not overflow because the sum of all user balances
            // cannot exceed the maximum uint256 value.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, shr(96, from_), shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(from, to, amount);
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL ALLOWANCE FUNCTIONS                */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Updates the allowance of `owner` for `spender` based on spent `amount`.
    function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the allowance slot and load its value.
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, owner)
            let allowanceSlot := keccak256(0x0c, 0x34)
            let allowance_ := sload(allowanceSlot)
            // If the allowance is not the maximum uint256 value.
            if add(allowance_, 1) {
                // Revert if the amount to be transferred exceeds the allowance.
                if gt(amount, allowance_) {
                    mstore(0x00, 0x13be252b) // `InsufficientAllowance()`.
                    revert(0x1c, 0x04)
                }
                // Subtract and store the updated allowance.
                sstore(allowanceSlot, sub(allowance_, amount))
            }
        }
    }
    /// @dev Sets `amount` as the allowance of `spender` over the tokens of `owner`.
    ///
    /// Emits a {Approval} event.
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            let owner_ := shl(96, owner)
            // Compute the allowance slot and store the amount.
            mstore(0x20, spender)
            mstore(0x0c, or(owner_, _ALLOWANCE_SLOT_SEED))
            sstore(keccak256(0x0c, 0x34), amount)
            // Emit the {Approval} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _APPROVAL_EVENT_SIGNATURE, shr(96, owner_), shr(96, mload(0x2c)))
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     HOOKS TO OVERRIDE                      */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Hook that is called before any transfer of tokens.
    /// This includes minting and burning.
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}
    /// @dev Hook that is called after any transfer of tokens.
    /// This includes minting and burning.
    function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;
/// @notice Gas optimized ECDSA wrapper.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/ECDSA.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/ECDSA.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/ECDSA.sol)
///
/// @dev Note:
/// - The recovery functions use the ecrecover precompile (0x1).
/// - As of Solady version 0.0.68, the `recover` variants will revert upon recovery failure.
///   This is for more safety by default.
///   Use the `tryRecover` variants if you need to get the zero address back
///   upon recovery failure instead.
/// - As of Solady version 0.0.134, all `bytes signature` variants accept both
///   regular 65-byte `(r, s, v)` and EIP-2098 `(r, vs)` short form signatures.
///   See: https://eips.ethereum.org/EIPS/eip-2098
///   This is for calldata efficiency on smart accounts prevalent on L2s.
///
/// WARNING! Do NOT use signatures as unique identifiers:
/// - Use a nonce in the digest to prevent replay attacks on the same contract.
/// - Use EIP-712 for the digest to prevent replay attacks across different chains and contracts.
///   EIP-712 also enables readable signing of typed data for better user safety.
/// This implementation does NOT check if a signature is non-malleable.
library ECDSA {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                        CUSTOM ERRORS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev The signature is invalid.
    error InvalidSignature();
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                    RECOVERY OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function recover(bytes32 hash, bytes memory signature) internal view returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            for {} 1 {} {
                mstore(0x00, hash)
                mstore(0x40, mload(add(signature, 0x20))) // `r`.
                if eq(mload(signature), 64) {
                    let vs := mload(add(signature, 0x40))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(mload(signature), 65) {
                    mstore(0x20, byte(0, mload(add(signature, 0x60)))) // `v`.
                    mstore(0x60, mload(add(signature, 0x40))) // `s`.
                    break
                }
                result := 0
                break
            }
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        result, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function recoverCalldata(bytes32 hash, bytes calldata signature)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            for {} 1 {} {
                if eq(signature.length, 64) {
                    let vs := calldataload(add(signature.offset, 0x20))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x40, calldataload(signature.offset)) // `r`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(signature.length, 65) {
                    mstore(0x20, byte(0, calldataload(add(signature.offset, 0x40)))) // `v`.
                    calldatacopy(0x40, signature.offset, 0x40) // Copy `r` and `s`.
                    break
                }
                result := 0
                break
            }
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        result, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the EIP-2098 short form signature defined by `r` and `vs`.
    function recover(bytes32 hash, bytes32 r, bytes32 vs) internal view returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, add(shr(255, vs), 27)) // `v`.
            mstore(0x40, r)
            mstore(0x60, shr(1, shl(1, vs))) // `s`.
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        1, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the signature defined by `v`, `r`, `s`.
    function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, and(v, 0xff))
            mstore(0x40, r)
            mstore(0x60, s)
            result :=
                mload(
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        1, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                )
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            if iszero(returndatasize()) {
                mstore(0x00, 0x8baa579f) // `InvalidSignature()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   TRY-RECOVER OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    // WARNING!
    // These functions will NOT revert upon recovery failure.
    // Instead, they will return the zero address upon recovery failure.
    // It is critical that the returned address is NEVER compared against
    // a zero address (e.g. an uninitialized address variable).
    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function tryRecover(bytes32 hash, bytes memory signature)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            for {} 1 {} {
                mstore(0x00, hash)
                mstore(0x40, mload(add(signature, 0x20))) // `r`.
                if eq(mload(signature), 64) {
                    let vs := mload(add(signature, 0x40))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(mload(signature), 65) {
                    mstore(0x20, byte(0, mload(add(signature, 0x60)))) // `v`.
                    mstore(0x60, mload(add(signature, 0x40))) // `s`.
                    break
                }
                result := 0
                break
            }
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    result, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Recovers the signer's address from a message digest `hash`, and the `signature`.
    function tryRecoverCalldata(bytes32 hash, bytes calldata signature)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            for {} 1 {} {
                if eq(signature.length, 64) {
                    let vs := calldataload(add(signature.offset, 0x20))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x40, calldataload(signature.offset)) // `r`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    break
                }
                if eq(signature.length, 65) {
                    mstore(0x20, byte(0, calldataload(add(signature.offset, 0x40)))) // `v`.
                    calldatacopy(0x40, signature.offset, 0x40) // Copy `r` and `s`.
                    break
                }
                result := 0
                break
            }
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    result, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the EIP-2098 short form signature defined by `r` and `vs`.
    function tryRecover(bytes32 hash, bytes32 r, bytes32 vs)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, add(shr(255, vs), 27)) // `v`.
            mstore(0x40, r)
            mstore(0x60, shr(1, shl(1, vs))) // `s`.
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    1, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Recovers the signer's address from a message digest `hash`,
    /// and the signature defined by `v`, `r`, `s`.
    function tryRecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s)
        internal
        view
        returns (address result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x00, hash)
            mstore(0x20, and(v, 0xff))
            mstore(0x40, r)
            mstore(0x60, s)
            pop(
                staticcall(
                    gas(), // Amount of gas left for the transaction.
                    1, // Address of `ecrecover`.
                    0x00, // Start of input.
                    0x80, // Size of input.
                    0x40, // Start of output.
                    0x20 // Size of output.
                )
            )
            mstore(0x60, 0) // Restore the zero slot.
            // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
            result := mload(xor(0x60, returndatasize()))
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     HASHING OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns an Ethereum Signed Message, created from a `hash`.
    /// This produces a hash corresponding to the one signed with the
    /// [`eth_sign`](https://eth.wiki/json-rpc/API#eth_sign)
    /// JSON-RPC method as part of EIP-191.
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, hash) // Store into scratch space for keccak256.
            mstore(0x00, "\\x00\\x00\\x00\\x00\\x19Ethereum Signed Message:\
32") // 28 bytes.
            result := keccak256(0x04, 0x3c) // `32 * 2 - (32 - 28) = 60 = 0x3c`.
        }
    }
    /// @dev Returns an Ethereum Signed Message, created from `s`.
    /// This produces a hash corresponding to the one signed with the
    /// [`eth_sign`](https://eth.wiki/json-rpc/API#eth_sign)
    /// JSON-RPC method as part of EIP-191.
    /// Note: Supports lengths of `s` up to 999999 bytes.
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            let sLength := mload(s)
            let o := 0x20
            mstore(o, "\\x19Ethereum Signed Message:\
") // 26 bytes, zero-right-padded.
            mstore(0x00, 0x00)
            // Convert the `s.length` to ASCII decimal representation: `base10(s.length)`.
            for { let temp := sLength } 1 {} {
                o := sub(o, 1)
                mstore8(o, add(48, mod(temp, 10)))
                temp := div(temp, 10)
                if iszero(temp) { break }
            }
            let n := sub(0x3a, o) // Header length: `26 + 32 - o`.
            // Throw an out-of-offset error (consumes all gas) if the header exceeds 32 bytes.
            returndatacopy(returndatasize(), returndatasize(), gt(n, 0x20))
            mstore(s, or(mload(0x00), mload(n))) // Temporarily store the header.
            result := keccak256(add(s, sub(0x20, n)), add(n, sLength))
            mstore(s, sLength) // Restore the length.
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   EMPTY CALLDATA HELPERS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns an empty calldata bytes.
    function emptySignature() internal pure returns (bytes calldata signature) {
        /// @solidity memory-safe-assembly
        assembly {
            signature.length := 0
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;
/// @notice Contract for EIP-712 typed structured data hashing and signing.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/EIP712.sol)
/// @author Modified from Solbase (https://github.com/Sol-DAO/solbase/blob/main/src/utils/EIP712.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/EIP712.sol)
///
/// @dev Note, this implementation:
/// - Uses `address(this)` for the `verifyingContract` field.
/// - Does NOT use the optional EIP-712 salt.
/// - Does NOT use any EIP-712 extensions.
/// This is for simplicity and to save gas.
/// If you need to customize, please fork / modify accordingly.
abstract contract EIP712 {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  CONSTANTS AND IMMUTABLES                  */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev `keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")`.
    bytes32 internal constant _DOMAIN_TYPEHASH =
        0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f;
    uint256 private immutable _cachedThis;
    uint256 private immutable _cachedChainId;
    bytes32 private immutable _cachedNameHash;
    bytes32 private immutable _cachedVersionHash;
    bytes32 private immutable _cachedDomainSeparator;
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                        CONSTRUCTOR                         */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Cache the hashes for cheaper runtime gas costs.
    /// In the case of upgradeable contracts (i.e. proxies),
    /// or if the chain id changes due to a hard fork,
    /// the domain separator will be seamlessly calculated on-the-fly.
    constructor() {
        _cachedThis = uint256(uint160(address(this)));
        _cachedChainId = block.chainid;
        string memory name;
        string memory version;
        if (!_domainNameAndVersionMayChange()) (name, version) = _domainNameAndVersion();
        bytes32 nameHash = _domainNameAndVersionMayChange() ? bytes32(0) : keccak256(bytes(name));
        bytes32 versionHash =
            _domainNameAndVersionMayChange() ? bytes32(0) : keccak256(bytes(version));
        _cachedNameHash = nameHash;
        _cachedVersionHash = versionHash;
        bytes32 separator;
        if (!_domainNameAndVersionMayChange()) {
            /// @solidity memory-safe-assembly
            assembly {
                let m := mload(0x40) // Load the free memory pointer.
                mstore(m, _DOMAIN_TYPEHASH)
                mstore(add(m, 0x20), nameHash)
                mstore(add(m, 0x40), versionHash)
                mstore(add(m, 0x60), chainid())
                mstore(add(m, 0x80), address())
                separator := keccak256(m, 0xa0)
            }
        }
        _cachedDomainSeparator = separator;
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   FUNCTIONS TO OVERRIDE                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Please override this function to return the domain name and version.
    /// ```
    ///     function _domainNameAndVersion()
    ///         internal
    ///         pure
    ///         virtual
    ///         returns (string memory name, string memory version)
    ///     {
    ///         name = "Solady";
    ///         version = "1";
    ///     }
    /// ```
    ///
    /// Note: If the returned result may change after the contract has been deployed,
    /// you must override `_domainNameAndVersionMayChange()` to return true.
    function _domainNameAndVersion()
        internal
        view
        virtual
        returns (string memory name, string memory version);
    /// @dev Returns if `_domainNameAndVersion()` may change
    /// after the contract has been deployed (i.e. after the constructor).
    /// Default: false.
    function _domainNameAndVersionMayChange() internal pure virtual returns (bool result) {}
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     HASHING OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns the EIP-712 domain separator.
    function _domainSeparator() internal view virtual returns (bytes32 separator) {
        if (_domainNameAndVersionMayChange()) {
            separator = _buildDomainSeparator();
        } else {
            separator = _cachedDomainSeparator;
            if (_cachedDomainSeparatorInvalidated()) separator = _buildDomainSeparator();
        }
    }
    /// @dev Returns the hash of the fully encoded EIP-712 message for this domain,
    /// given `structHash`, as defined in
    /// https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct.
    ///
    /// The hash can be used together with {ECDSA-recover} to obtain the signer of a message:
    /// ```
    ///     bytes32 digest = _hashTypedData(keccak256(abi.encode(
    ///         keccak256("Mail(address to,string contents)"),
    ///         mailTo,
    ///         keccak256(bytes(mailContents))
    ///     )));
    ///     address signer = ECDSA.recover(digest, signature);
    /// ```
    function _hashTypedData(bytes32 structHash) internal view virtual returns (bytes32 digest) {
        // We will use `digest` to store the domain separator to save a bit of gas.
        if (_domainNameAndVersionMayChange()) {
            digest = _buildDomainSeparator();
        } else {
            digest = _cachedDomainSeparator;
            if (_cachedDomainSeparatorInvalidated()) digest = _buildDomainSeparator();
        }
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the digest.
            mstore(0x00, 0x1901000000000000) // Store "\\x19\\x01".
            mstore(0x1a, digest) // Store the domain separator.
            mstore(0x3a, structHash) // Store the struct hash.
            digest := keccak256(0x18, 0x42)
            // Restore the part of the free memory slot that was overwritten.
            mstore(0x3a, 0)
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                    EIP-5267 OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev See: https://eips.ethereum.org/EIPS/eip-5267
    function eip712Domain()
        public
        view
        virtual
        returns (
            bytes1 fields,
            string memory name,
            string memory version,
            uint256 chainId,
            address verifyingContract,
            bytes32 salt,
            uint256[] memory extensions
        )
    {
        fields = hex"0f"; // `0b01111`.
        (name, version) = _domainNameAndVersion();
        chainId = block.chainid;
        verifyingContract = address(this);
        salt = salt; // `bytes32(0)`.
        extensions = extensions; // `new uint256[](0)`.
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      PRIVATE HELPERS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns the EIP-712 domain separator.
    function _buildDomainSeparator() private view returns (bytes32 separator) {
        // We will use `separator` to store the name hash to save a bit of gas.
        bytes32 versionHash;
        if (_domainNameAndVersionMayChange()) {
            (string memory name, string memory version) = _domainNameAndVersion();
            separator = keccak256(bytes(name));
            versionHash = keccak256(bytes(version));
        } else {
            separator = _cachedNameHash;
            versionHash = _cachedVersionHash;
        }
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Load the free memory pointer.
            mstore(m, _DOMAIN_TYPEHASH)
            mstore(add(m, 0x20), separator) // Name hash.
            mstore(add(m, 0x40), versionHash)
            mstore(add(m, 0x60), chainid())
            mstore(add(m, 0x80), address())
            separator := keccak256(m, 0xa0)
        }
    }
    /// @dev Returns if the cached domain separator has been invalidated.
    function _cachedDomainSeparatorInvalidated() private view returns (bool result) {
        uint256 cachedChainId = _cachedChainId;
        uint256 cachedThis = _cachedThis;
        /// @solidity memory-safe-assembly
        assembly {
            result := iszero(and(eq(chainid(), cachedChainId), eq(address(), cachedThis)))
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;
/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/SafeTransferLib.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
///
/// @dev Note:
/// - For ETH transfers, please use `forceSafeTransferETH` for DoS protection.
/// - For ERC20s, this implementation won't check that a token has code,
///   responsibility is delegated to the caller.
library SafeTransferLib {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev The ETH transfer has failed.
    error ETHTransferFailed();
    /// @dev The ERC20 `transferFrom` has failed.
    error TransferFromFailed();
    /// @dev The ERC20 `transfer` has failed.
    error TransferFailed();
    /// @dev The ERC20 `approve` has failed.
    error ApproveFailed();
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Suggested gas stipend for contract receiving ETH that disallows any storage writes.
    uint256 internal constant GAS_STIPEND_NO_STORAGE_WRITES = 2300;
    /// @dev Suggested gas stipend for contract receiving ETH to perform a few
    /// storage reads and writes, but low enough to prevent griefing.
    uint256 internal constant GAS_STIPEND_NO_GRIEF = 100000;
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       ETH OPERATIONS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    // If the ETH transfer MUST succeed with a reasonable gas budget, use the force variants.
    //
    // The regular variants:
    // - Forwards all remaining gas to the target.
    // - Reverts if the target reverts.
    // - Reverts if the current contract has insufficient balance.
    //
    // The force variants:
    // - Forwards with an optional gas stipend
    //   (defaults to `GAS_STIPEND_NO_GRIEF`, which is sufficient for most cases).
    // - If the target reverts, or if the gas stipend is exhausted,
    //   creates a temporary contract to force send the ETH via `SELFDESTRUCT`.
    //   Future compatible with `SENDALL`: https://eips.ethereum.org/EIPS/eip-4758.
    // - Reverts if the current contract has insufficient balance.
    //
    // The try variants:
    // - Forwards with a mandatory gas stipend.
    // - Instead of reverting, returns whether the transfer succeeded.
    /// @dev Sends `amount` (in wei) ETH to `to`.
    function safeTransferETH(address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(call(gas(), to, amount, codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
        }
    }
    /// @dev Sends all the ETH in the current contract to `to`.
    function safeTransferAllETH(address to) internal {
        /// @solidity memory-safe-assembly
        assembly {
            // Transfer all the ETH and check if it succeeded or not.
            if iszero(call(gas(), to, selfbalance(), codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
        }
    }
    /// @dev Force sends `amount` (in wei) ETH to `to`, with a `gasStipend`.
    function forceSafeTransferETH(address to, uint256 amount, uint256 gasStipend) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if lt(selfbalance(), amount) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
            if iszero(call(gasStipend, to, amount, codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(amount, 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }
    /// @dev Force sends all the ETH in the current contract to `to`, with a `gasStipend`.
    function forceSafeTransferAllETH(address to, uint256 gasStipend) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(call(gasStipend, to, selfbalance(), codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(selfbalance(), 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }
    /// @dev Force sends `amount` (in wei) ETH to `to`, with `GAS_STIPEND_NO_GRIEF`.
    function forceSafeTransferETH(address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            if lt(selfbalance(), amount) {
                mstore(0x00, 0xb12d13eb) // `ETHTransferFailed()`.
                revert(0x1c, 0x04)
            }
            if iszero(call(GAS_STIPEND_NO_GRIEF, to, amount, codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(amount, 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }
    /// @dev Force sends all the ETH in the current contract to `to`, with `GAS_STIPEND_NO_GRIEF`.
    function forceSafeTransferAllETH(address to) internal {
        /// @solidity memory-safe-assembly
        assembly {
            // forgefmt: disable-next-item
            if iszero(call(GAS_STIPEND_NO_GRIEF, to, selfbalance(), codesize(), 0x00, codesize(), 0x00)) {
                mstore(0x00, to) // Store the address in scratch space.
                mstore8(0x0b, 0x73) // Opcode `PUSH20`.
                mstore8(0x20, 0xff) // Opcode `SELFDESTRUCT`.
                if iszero(create(selfbalance(), 0x0b, 0x16)) { revert(codesize(), codesize()) } // For gas estimation.
            }
        }
    }
    /// @dev Sends `amount` (in wei) ETH to `to`, with a `gasStipend`.
    function trySafeTransferETH(address to, uint256 amount, uint256 gasStipend)
        internal
        returns (bool success)
    {
        /// @solidity memory-safe-assembly
        assembly {
            success := call(gasStipend, to, amount, codesize(), 0x00, codesize(), 0x00)
        }
    }
    /// @dev Sends all the ETH in the current contract to `to`, with a `gasStipend`.
    function trySafeTransferAllETH(address to, uint256 gasStipend)
        internal
        returns (bool success)
    {
        /// @solidity memory-safe-assembly
        assembly {
            success := call(gasStipend, to, selfbalance(), codesize(), 0x00, codesize(), 0x00)
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      ERC20 OPERATIONS                      */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Sends `amount` of ERC20 `token` from `from` to `to`.
    /// Reverts upon failure.
    ///
    /// The `from` account must have at least `amount` approved for
    /// the current contract to manage.
    function safeTransferFrom(address token, address from, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x60, amount) // Store the `amount` argument.
            mstore(0x40, to) // Store the `to` argument.
            mstore(0x2c, shl(96, from)) // Store the `from` argument.
            mstore(0x0c, 0x23b872dd000000000000000000000000) // `transferFrom(address,address,uint256)`.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x1c, 0x64, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x7939f424) // `TransferFromFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot to zero.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Sends all of ERC20 `token` from `from` to `to`.
    /// Reverts upon failure.
    ///
    /// The `from` account must have their entire balance approved for
    /// the current contract to manage.
    function safeTransferAllFrom(address token, address from, address to)
        internal
        returns (uint256 amount)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40) // Cache the free memory pointer.
            mstore(0x40, to) // Store the `to` argument.
            mstore(0x2c, shl(96, from)) // Store the `from` argument.
            mstore(0x0c, 0x70a08231000000000000000000000000) // `balanceOf(address)`.
            // Read the balance, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    gt(returndatasize(), 0x1f), // At least 32 bytes returned.
                    staticcall(gas(), token, 0x1c, 0x24, 0x60, 0x20)
                )
            ) {
                mstore(0x00, 0x7939f424) // `TransferFromFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x00, 0x23b872dd) // `transferFrom(address,address,uint256)`.
            amount := mload(0x60) // The `amount` is already at 0x60. We'll need to return it.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x1c, 0x64, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x7939f424) // `TransferFromFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x60, 0) // Restore the zero slot to zero.
            mstore(0x40, m) // Restore the free memory pointer.
        }
    }
    /// @dev Sends `amount` of ERC20 `token` from the current contract to `to`.
    /// Reverts upon failure.
    function safeTransfer(address token, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, to) // Store the `to` argument.
            mstore(0x34, amount) // Store the `amount` argument.
            mstore(0x00, 0xa9059cbb000000000000000000000000) // `transfer(address,uint256)`.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x90b8ec18) // `TransferFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }
    /// @dev Sends all of ERC20 `token` from the current contract to `to`.
    /// Reverts upon failure.
    function safeTransferAll(address token, address to) internal returns (uint256 amount) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, 0x70a08231) // Store the function selector of `balanceOf(address)`.
            mstore(0x20, address()) // Store the address of the current contract.
            // Read the balance, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    gt(returndatasize(), 0x1f), // At least 32 bytes returned.
                    staticcall(gas(), token, 0x1c, 0x24, 0x34, 0x20)
                )
            ) {
                mstore(0x00, 0x90b8ec18) // `TransferFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x14, to) // Store the `to` argument.
            amount := mload(0x34) // The `amount` is already at 0x34. We'll need to return it.
            mstore(0x00, 0xa9059cbb000000000000000000000000) // `transfer(address,uint256)`.
            // Perform the transfer, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x90b8ec18) // `TransferFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }
    /// @dev Sets `amount` of ERC20 `token` for `to` to manage on behalf of the current contract.
    /// Reverts upon failure.
    function safeApprove(address token, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, to) // Store the `to` argument.
            mstore(0x34, amount) // Store the `amount` argument.
            mstore(0x00, 0x095ea7b3000000000000000000000000) // `approve(address,uint256)`.
            // Perform the approval, reverting upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0x3e3f8f73) // `ApproveFailed()`.
                revert(0x1c, 0x04)
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }
    /// @dev Sets `amount` of ERC20 `token` for `to` to manage on behalf of the current contract.
    /// If the initial attempt to approve fails, attempts to reset the approved amount to zero,
    /// then retries the approval again (some tokens, e.g. USDT, requires this).
    /// Reverts upon failure.
    function safeApproveWithRetry(address token, address to, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, to) // Store the `to` argument.
            mstore(0x34, amount) // Store the `amount` argument.
            mstore(0x00, 0x095ea7b3000000000000000000000000) // `approve(address,uint256)`.
            // Perform the approval, retrying upon failure.
            if iszero(
                and( // The arguments of `and` are evaluated from right to left.
                    or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                    call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                )
            ) {
                mstore(0x34, 0) // Store 0 for the `amount`.
                mstore(0x00, 0x095ea7b3000000000000000000000000) // `approve(address,uint256)`.
                pop(call(gas(), token, 0, 0x10, 0x44, codesize(), 0x00)) // Reset the approval.
                mstore(0x34, amount) // Store back the original `amount`.
                // Retry the approval, reverting upon failure.
                if iszero(
                    and(
                        or(eq(mload(0x00), 1), iszero(returndatasize())), // Returned 1 or nothing.
                        call(gas(), token, 0, 0x10, 0x44, 0x00, 0x20)
                    )
                ) {
                    mstore(0x00, 0x3e3f8f73) // `ApproveFailed()`.
                    revert(0x1c, 0x04)
                }
            }
            mstore(0x34, 0) // Restore the part of the free memory pointer that was overwritten.
        }
    }
    /// @dev Returns the amount of ERC20 `token` owned by `account`.
    /// Returns zero if the `token` does not exist.
    function balanceOf(address token, address account) internal view returns (uint256 amount) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x14, account) // Store the `account` argument.
            mstore(0x00, 0x70a08231000000000000000000000000) // `balanceOf(address)`.
            amount :=
                mul(
                    mload(0x20),
                    and( // The arguments of `and` are evaluated from right to left.
                        gt(returndatasize(), 0x1f), // At least 32 bytes returned.
                        staticcall(gas(), token, 0x10, 0x24, 0x20, 0x20)
                    )
                )
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;
/// @notice Signature verification helper that supports both ECDSA signatures from EOAs
/// and ERC1271 signatures from smart contract wallets like Argent and Gnosis safe.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/SignatureCheckerLib.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/SignatureChecker.sol)
///
/// @dev Note:
/// - The signature checking functions use the ecrecover precompile (0x1).
/// - The `bytes memory signature` variants use the identity precompile (0x4)
///   to copy memory internally.
/// - Unlike ECDSA signatures, contract signatures are revocable.
/// - As of Solady version 0.0.134, all `bytes signature` variants accept both
///   regular 65-byte `(r, s, v)` and EIP-2098 `(r, vs)` short form signatures.
///   See: https://eips.ethereum.org/EIPS/eip-2098
///   This is for calldata efficiency on smart accounts prevalent on L2s.
///
/// WARNING! Do NOT use signatures as unique identifiers:
/// - Use a nonce in the digest to prevent replay attacks on the same contract.
/// - Use EIP-712 for the digest to prevent replay attacks across different chains and contracts.
///   EIP-712 also enables readable signing of typed data for better user safety.
/// This implementation does NOT check if a signature is non-malleable.
library SignatureCheckerLib {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*               SIGNATURE CHECKING OPERATIONS                */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns whether `signature` is valid for `signer` and `hash`.
    /// If `signer` is a smart contract, the signature is validated with ERC1271.
    /// Otherwise, the signature is validated with `ECDSA.recover`.
    function isValidSignatureNow(address signer, bytes32 hash, bytes memory signature)
        internal
        view
        returns (bool isValid)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Clean the upper 96 bits of `signer` in case they are dirty.
            for { signer := shr(96, shl(96, signer)) } signer {} {
                let m := mload(0x40)
                mstore(0x00, hash)
                mstore(0x40, mload(add(signature, 0x20))) // `r`.
                if eq(mload(signature), 64) {
                    let vs := mload(add(signature, 0x40))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    let t :=
                        staticcall(
                            gas(), // Amount of gas left for the transaction.
                            1, // Address of `ecrecover`.
                            0x00, // Start of input.
                            0x80, // Size of input.
                            0x01, // Start of output.
                            0x20 // Size of output.
                        )
                    // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
                    if iszero(or(iszero(returndatasize()), xor(signer, mload(t)))) {
                        isValid := 1
                        mstore(0x60, 0) // Restore the zero slot.
                        mstore(0x40, m) // Restore the free memory pointer.
                        break
                    }
                }
                if eq(mload(signature), 65) {
                    mstore(0x20, byte(0, mload(add(signature, 0x60)))) // `v`.
                    mstore(0x60, mload(add(signature, 0x40))) // `s`.
                    let t :=
                        staticcall(
                            gas(), // Amount of gas left for the transaction.
                            1, // Address of `ecrecover`.
                            0x00, // Start of input.
                            0x80, // Size of input.
                            0x01, // Start of output.
                            0x20 // Size of output.
                        )
                    // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
                    if iszero(or(iszero(returndatasize()), xor(signer, mload(t)))) {
                        isValid := 1
                        mstore(0x60, 0) // Restore the zero slot.
                        mstore(0x40, m) // Restore the free memory pointer.
                        break
                    }
                }
                mstore(0x60, 0) // Restore the zero slot.
                mstore(0x40, m) // Restore the free memory pointer.
                let f := shl(224, 0x1626ba7e)
                mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
                mstore(add(m, 0x04), hash)
                let d := add(m, 0x24)
                mstore(d, 0x40) // The offset of the `signature` in the calldata.
                // Copy the `signature` over.
                let n := add(0x20, mload(signature))
                pop(staticcall(gas(), 4, signature, n, add(m, 0x44), n))
                // forgefmt: disable-next-item
                isValid := and(
                    // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                    eq(mload(d), f),
                    // Whether the staticcall does not revert.
                    // This must be placed at the end of the `and` clause,
                    // as the arguments are evaluated from right to left.
                    staticcall(
                        gas(), // Remaining gas.
                        signer, // The `signer` address.
                        m, // Offset of calldata in memory.
                        add(returndatasize(), 0x44), // Length of calldata in memory.
                        d, // Offset of returndata.
                        0x20 // Length of returndata to write.
                    )
                )
                break
            }
        }
    }
    /// @dev Returns whether `signature` is valid for `signer` and `hash`.
    /// If `signer` is a smart contract, the signature is validated with ERC1271.
    /// Otherwise, the signature is validated with `ECDSA.recover`.
    function isValidSignatureNowCalldata(address signer, bytes32 hash, bytes calldata signature)
        internal
        view
        returns (bool isValid)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Clean the upper 96 bits of `signer` in case they are dirty.
            for { signer := shr(96, shl(96, signer)) } signer {} {
                let m := mload(0x40)
                mstore(0x00, hash)
                if eq(signature.length, 64) {
                    let vs := calldataload(add(signature.offset, 0x20))
                    mstore(0x20, add(shr(255, vs), 27)) // `v`.
                    mstore(0x40, calldataload(signature.offset)) // `r`.
                    mstore(0x60, shr(1, shl(1, vs))) // `s`.
                    let t :=
                        staticcall(
                            gas(), // Amount of gas left for the transaction.
                            1, // Address of `ecrecover`.
                            0x00, // Start of input.
                            0x80, // Size of input.
                            0x01, // Start of output.
                            0x20 // Size of output.
                        )
                    // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
                    if iszero(or(iszero(returndatasize()), xor(signer, mload(t)))) {
                        isValid := 1
                        mstore(0x60, 0) // Restore the zero slot.
                        mstore(0x40, m) // Restore the free memory pointer.
                        break
                    }
                }
                if eq(signature.length, 65) {
                    mstore(0x20, byte(0, calldataload(add(signature.offset, 0x40)))) // `v`.
                    calldatacopy(0x40, signature.offset, 0x40) // `r`, `s`.
                    let t :=
                        staticcall(
                            gas(), // Amount of gas left for the transaction.
                            1, // Address of `ecrecover`.
                            0x00, // Start of input.
                            0x80, // Size of input.
                            0x01, // Start of output.
                            0x20 // Size of output.
                        )
                    // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
                    if iszero(or(iszero(returndatasize()), xor(signer, mload(t)))) {
                        isValid := 1
                        mstore(0x60, 0) // Restore the zero slot.
                        mstore(0x40, m) // Restore the free memory pointer.
                        break
                    }
                }
                mstore(0x60, 0) // Restore the zero slot.
                mstore(0x40, m) // Restore the free memory pointer.
                let f := shl(224, 0x1626ba7e)
                mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
                mstore(add(m, 0x04), hash)
                let d := add(m, 0x24)
                mstore(d, 0x40) // The offset of the `signature` in the calldata.
                mstore(add(m, 0x44), signature.length)
                // Copy the `signature` over.
                calldatacopy(add(m, 0x64), signature.offset, signature.length)
                // forgefmt: disable-next-item
                isValid := and(
                    // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                    eq(mload(d), f),
                    // Whether the staticcall does not revert.
                    // This must be placed at the end of the `and` clause,
                    // as the arguments are evaluated from right to left.
                    staticcall(
                        gas(), // Remaining gas.
                        signer, // The `signer` address.
                        m, // Offset of calldata in memory.
                        add(signature.length, 0x64), // Length of calldata in memory.
                        d, // Offset of returndata.
                        0x20 // Length of returndata to write.
                    )
                )
                break
            }
        }
    }
    /// @dev Returns whether the signature (`r`, `vs`) is valid for `signer` and `hash`.
    /// If `signer` is a smart contract, the signature is validated with ERC1271.
    /// Otherwise, the signature is validated with `ECDSA.recover`.
    function isValidSignatureNow(address signer, bytes32 hash, bytes32 r, bytes32 vs)
        internal
        view
        returns (bool isValid)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Clean the upper 96 bits of `signer` in case they are dirty.
            for { signer := shr(96, shl(96, signer)) } signer {} {
                let m := mload(0x40)
                mstore(0x00, hash)
                mstore(0x20, add(shr(255, vs), 27)) // `v`.
                mstore(0x40, r) // `r`.
                mstore(0x60, shr(1, shl(1, vs))) // `s`.
                let t :=
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        1, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
                if iszero(or(iszero(returndatasize()), xor(signer, mload(t)))) {
                    isValid := 1
                    mstore(0x60, 0) // Restore the zero slot.
                    mstore(0x40, m) // Restore the free memory pointer.
                    break
                }
                let f := shl(224, 0x1626ba7e)
                mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
                mstore(add(m, 0x04), hash)
                let d := add(m, 0x24)
                mstore(d, 0x40) // The offset of the `signature` in the calldata.
                mstore(add(m, 0x44), 65) // Length of the signature.
                mstore(add(m, 0x64), r) // `r`.
                mstore(add(m, 0x84), mload(0x60)) // `s`.
                mstore8(add(m, 0xa4), mload(0x20)) // `v`.
                // forgefmt: disable-next-item
                isValid := and(
                    // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                    eq(mload(d), f),
                    // Whether the staticcall does not revert.
                    // This must be placed at the end of the `and` clause,
                    // as the arguments are evaluated from right to left.
                    staticcall(
                        gas(), // Remaining gas.
                        signer, // The `signer` address.
                        m, // Offset of calldata in memory.
                        0xa5, // Length of calldata in memory.
                        d, // Offset of returndata.
                        0x20 // Length of returndata to write.
                    )
                )
                mstore(0x60, 0) // Restore the zero slot.
                mstore(0x40, m) // Restore the free memory pointer.
                break
            }
        }
    }
    /// @dev Returns whether the signature (`v`, `r`, `s`) is valid for `signer` and `hash`.
    /// If `signer` is a smart contract, the signature is validated with ERC1271.
    /// Otherwise, the signature is validated with `ECDSA.recover`.
    function isValidSignatureNow(address signer, bytes32 hash, uint8 v, bytes32 r, bytes32 s)
        internal
        view
        returns (bool isValid)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Clean the upper 96 bits of `signer` in case they are dirty.
            for { signer := shr(96, shl(96, signer)) } signer {} {
                let m := mload(0x40)
                mstore(0x00, hash)
                mstore(0x20, and(v, 0xff)) // `v`.
                mstore(0x40, r) // `r`.
                mstore(0x60, s) // `s`.
                let t :=
                    staticcall(
                        gas(), // Amount of gas left for the transaction.
                        1, // Address of `ecrecover`.
                        0x00, // Start of input.
                        0x80, // Size of input.
                        0x01, // Start of output.
                        0x20 // Size of output.
                    )
                // `returndatasize()` will be `0x20` upon success, and `0x00` otherwise.
                if iszero(or(iszero(returndatasize()), xor(signer, mload(t)))) {
                    isValid := 1
                    mstore(0x60, 0) // Restore the zero slot.
                    mstore(0x40, m) // Restore the free memory pointer.
                    break
                }
                let f := shl(224, 0x1626ba7e)
                mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
                mstore(add(m, 0x04), hash)
                let d := add(m, 0x24)
                mstore(d, 0x40) // The offset of the `signature` in the calldata.
                mstore(add(m, 0x44), 65) // Length of the signature.
                mstore(add(m, 0x64), r) // `r`.
                mstore(add(m, 0x84), s) // `s`.
                mstore8(add(m, 0xa4), v) // `v`.
                // forgefmt: disable-next-item
                isValid := and(
                    // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                    eq(mload(d), f),
                    // Whether the staticcall does not revert.
                    // This must be placed at the end of the `and` clause,
                    // as the arguments are evaluated from right to left.
                    staticcall(
                        gas(), // Remaining gas.
                        signer, // The `signer` address.
                        m, // Offset of calldata in memory.
                        0xa5, // Length of calldata in memory.
                        d, // Offset of returndata.
                        0x20 // Length of returndata to write.
                    )
                )
                mstore(0x60, 0) // Restore the zero slot.
                mstore(0x40, m) // Restore the free memory pointer.
                break
            }
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     ERC1271 OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns whether `signature` is valid for `hash` for an ERC1271 `signer` contract.
    function isValidERC1271SignatureNow(address signer, bytes32 hash, bytes memory signature)
        internal
        view
        returns (bool isValid)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40)
            let f := shl(224, 0x1626ba7e)
            mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
            mstore(add(m, 0x04), hash)
            let d := add(m, 0x24)
            mstore(d, 0x40) // The offset of the `signature` in the calldata.
            // Copy the `signature` over.
            let n := add(0x20, mload(signature))
            pop(staticcall(gas(), 4, signature, n, add(m, 0x44), n))
            // forgefmt: disable-next-item
            isValid := and(
                // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                eq(mload(d), f),
                // Whether the staticcall does not revert.
                // This must be placed at the end of the `and` clause,
                // as the arguments are evaluated from right to left.
                staticcall(
                    gas(), // Remaining gas.
                    signer, // The `signer` address.
                    m, // Offset of calldata in memory.
                    add(returndatasize(), 0x44), // Length of calldata in memory.
                    d, // Offset of returndata.
                    0x20 // Length of returndata to write.
                )
            )
        }
    }
    /// @dev Returns whether `signature` is valid for `hash` for an ERC1271 `signer` contract.
    function isValidERC1271SignatureNowCalldata(
        address signer,
        bytes32 hash,
        bytes calldata signature
    ) internal view returns (bool isValid) {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40)
            let f := shl(224, 0x1626ba7e)
            mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
            mstore(add(m, 0x04), hash)
            let d := add(m, 0x24)
            mstore(d, 0x40) // The offset of the `signature` in the calldata.
            mstore(add(m, 0x44), signature.length)
            // Copy the `signature` over.
            calldatacopy(add(m, 0x64), signature.offset, signature.length)
            // forgefmt: disable-next-item
            isValid := and(
                // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                eq(mload(d), f),
                // Whether the staticcall does not revert.
                // This must be placed at the end of the `and` clause,
                // as the arguments are evaluated from right to left.
                staticcall(
                    gas(), // Remaining gas.
                    signer, // The `signer` address.
                    m, // Offset of calldata in memory.
                    add(signature.length, 0x64), // Length of calldata in memory.
                    d, // Offset of returndata.
                    0x20 // Length of returndata to write.
                )
            )
        }
    }
    /// @dev Returns whether the signature (`r`, `vs`) is valid for `hash`
    /// for an ERC1271 `signer` contract.
    function isValidERC1271SignatureNow(address signer, bytes32 hash, bytes32 r, bytes32 vs)
        internal
        view
        returns (bool isValid)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40)
            let f := shl(224, 0x1626ba7e)
            mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
            mstore(add(m, 0x04), hash)
            let d := add(m, 0x24)
            mstore(d, 0x40) // The offset of the `signature` in the calldata.
            mstore(add(m, 0x44), 65) // Length of the signature.
            mstore(add(m, 0x64), r) // `r`.
            mstore(add(m, 0x84), shr(1, shl(1, vs))) // `s`.
            mstore8(add(m, 0xa4), add(shr(255, vs), 27)) // `v`.
            // forgefmt: disable-next-item
            isValid := and(
                // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                eq(mload(d), f),
                // Whether the staticcall does not revert.
                // This must be placed at the end of the `and` clause,
                // as the arguments are evaluated from right to left.
                staticcall(
                    gas(), // Remaining gas.
                    signer, // The `signer` address.
                    m, // Offset of calldata in memory.
                    0xa5, // Length of calldata in memory.
                    d, // Offset of returndata.
                    0x20 // Length of returndata to write.
                )
            )
        }
    }
    /// @dev Returns whether the signature (`v`, `r`, `s`) is valid for `hash`
    /// for an ERC1271 `signer` contract.
    function isValidERC1271SignatureNow(address signer, bytes32 hash, uint8 v, bytes32 r, bytes32 s)
        internal
        view
        returns (bool isValid)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40)
            let f := shl(224, 0x1626ba7e)
            mstore(m, f) // `bytes4(keccak256("isValidSignature(bytes32,bytes)"))`.
            mstore(add(m, 0x04), hash)
            let d := add(m, 0x24)
            mstore(d, 0x40) // The offset of the `signature` in the calldata.
            mstore(add(m, 0x44), 65) // Length of the signature.
            mstore(add(m, 0x64), r) // `r`.
            mstore(add(m, 0x84), s) // `s`.
            mstore8(add(m, 0xa4), v) // `v`.
            // forgefmt: disable-next-item
            isValid := and(
                // Whether the returndata is the magic value `0x1626ba7e` (left-aligned).
                eq(mload(d), f),
                // Whether the staticcall does not revert.
                // This must be placed at the end of the `and` clause,
                // as the arguments are evaluated from right to left.
                staticcall(
                    gas(), // Remaining gas.
                    signer, // The `signer` address.
                    m, // Offset of calldata in memory.
                    0xa5, // Length of calldata in memory.
                    d, // Offset of returndata.
                    0x20 // Length of returndata to write.
                )
            )
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     HASHING OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns an Ethereum Signed Message, created from a `hash`.
    /// This produces a hash corresponding to the one signed with the
    /// [`eth_sign`](https://eth.wiki/json-rpc/API#eth_sign)
    /// JSON-RPC method as part of EIP-191.
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, hash) // Store into scratch space for keccak256.
            mstore(0x00, "\\x00\\x00\\x00\\x00\\x19Ethereum Signed Message:\
32") // 28 bytes.
            result := keccak256(0x04, 0x3c) // `32 * 2 - (32 - 28) = 60 = 0x3c`.
        }
    }
    /// @dev Returns an Ethereum Signed Message, created from `s`.
    /// This produces a hash corresponding to the one signed with the
    /// [`eth_sign`](https://eth.wiki/json-rpc/API#eth_sign)
    /// JSON-RPC method as part of EIP-191.
    /// Note: Supports lengths of `s` up to 999999 bytes.
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            let sLength := mload(s)
            let o := 0x20
            mstore(o, "\\x19Ethereum Signed Message:\
") // 26 bytes, zero-right-padded.
            mstore(0x00, 0x00)
            // Convert the `s.length` to ASCII decimal representation: `base10(s.length)`.
            for { let temp := sLength } 1 {} {
                o := sub(o, 1)
                mstore8(o, add(48, mod(temp, 10)))
                temp := div(temp, 10)
                if iszero(temp) { break }
            }
            let n := sub(0x3a, o) // Header length: `26 + 32 - o`.
            // Throw an out-of-offset error (consumes all gas) if the header exceeds 32 bytes.
            returndatacopy(returndatasize(), returndatasize(), gt(n, 0x20))
            mstore(s, or(mload(0x00), mload(n))) // Temporarily store the header.
            result := keccak256(add(s, sub(0x20, n)), add(n, sLength))
            mstore(s, sLength) // Restore the length.
        }
    }
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   EMPTY CALLDATA HELPERS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
    /// @dev Returns an empty calldata bytes.
    function emptySignature() internal pure returns (bytes calldata signature) {
        /// @solidity memory-safe-assembly
        assembly {
            signature.length := 0
        }
    }
}

/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { EIP712Domain } from "./EIP712Domain.sol"; // solhint-disable-line no-unused-import
import { Blacklistable } from "../v1/Blacklistable.sol"; // solhint-disable-line no-unused-import
import { FiatTokenV1 } from "../v1/FiatTokenV1.sol"; // solhint-disable-line no-unused-import
import { FiatTokenV2 } from "./FiatTokenV2.sol"; // solhint-disable-line no-unused-import
import { FiatTokenV2_1 } from "./FiatTokenV2_1.sol";
import { EIP712 } from "../util/EIP712.sol";
// solhint-disable func-name-mixedcase
/**
 * @title FiatToken V2.2
 * @notice ERC20 Token backed by fiat reserves, version 2.2
 */
contract FiatTokenV2_2 is FiatTokenV2_1 {
    /**
     * @notice Initialize v2.2
     * @param accountsToBlacklist   A list of accounts to migrate from the old blacklist
     * @param newSymbol             New token symbol
     * data structure to the new blacklist data structure.
     */
    function initializeV2_2(
        address[] calldata accountsToBlacklist,
        string calldata newSymbol
    ) external {
        // solhint-disable-next-line reason-string
        require(_initializedVersion == 2);
        // Update fiat token symbol
        symbol = newSymbol;
        // Add previously blacklisted accounts to the new blacklist data structure
        // and remove them from the old blacklist data structure.
        for (uint256 i = 0; i < accountsToBlacklist.length; i++) {
            require(
                _deprecatedBlacklisted[accountsToBlacklist[i]],
                "FiatTokenV2_2: Blacklisting previously unblacklisted account!"
            );
            _blacklist(accountsToBlacklist[i]);
            delete _deprecatedBlacklisted[accountsToBlacklist[i]];
        }
        _blacklist(address(this));
        delete _deprecatedBlacklisted[address(this)];
        _initializedVersion = 3;
    }
    /**
     * @dev Internal function to get the current chain id.
     * @return The current chain id.
     */
    function _chainId() internal virtual view returns (uint256) {
        uint256 chainId;
        assembly {
            chainId := chainid()
        }
        return chainId;
    }
    /**
     * @inheritdoc EIP712Domain
     */
    function _domainSeparator() internal override view returns (bytes32) {
        return EIP712.makeDomainSeparator(name, "2", _chainId());
    }
    /**
     * @notice Update allowance with a signed permit
     * @dev EOA wallet signatures should be packed in the order of r, s, v.
     * @param owner       Token owner's address (Authorizer)
     * @param spender     Spender's address
     * @param value       Amount of allowance
     * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
     * @param signature   Signature bytes signed by an EOA wallet or a contract wallet
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        bytes memory signature
    ) external whenNotPaused {
        _permit(owner, spender, value, deadline, signature);
    }
    /**
     * @notice Execute a transfer with a signed authorization
     * @dev EOA wallet signatures should be packed in the order of r, s, v.
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
     */
    function transferWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        bytes memory signature
    ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
        _transferWithAuthorization(
            from,
            to,
            value,
            validAfter,
            validBefore,
            nonce,
            signature
        );
    }
    /**
     * @notice Receive a transfer with a signed authorization from the payer
     * @dev This has an additional check to ensure that the payee's address
     * matches the caller of this function to prevent front-running attacks.
     * EOA wallet signatures should be packed in the order of r, s, v.
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
     */
    function receiveWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        bytes memory signature
    ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
        _receiveWithAuthorization(
            from,
            to,
            value,
            validAfter,
            validBefore,
            nonce,
            signature
        );
    }
    /**
     * @notice Attempt to cancel an authorization
     * @dev Works only if the authorization is not yet used.
     * EOA wallet signatures should be packed in the order of r, s, v.
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
     */
    function cancelAuthorization(
        address authorizer,
        bytes32 nonce,
        bytes memory signature
    ) external whenNotPaused {
        _cancelAuthorization(authorizer, nonce, signature);
    }
    /**
     * @dev Helper method that sets the blacklist state of an account on balanceAndBlacklistStates.
     * If _shouldBlacklist is true, we apply a (1 << 255) bitmask with an OR operation on the
     * account's balanceAndBlacklistState. This flips the high bit for the account to 1,
     * indicating that the account is blacklisted.
     *
     * If _shouldBlacklist if false, we reset the account's balanceAndBlacklistStates to their
     * balances. This clears the high bit for the account, indicating that the account is unblacklisted.
     * @param _account         The address of the account.
     * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
     */
    function _setBlacklistState(address _account, bool _shouldBlacklist)
        internal
        override
    {
        balanceAndBlacklistStates[_account] = _shouldBlacklist
            ? balanceAndBlacklistStates[_account] | (1 << 255)
            : _balanceOf(_account);
    }
    /**
     * @dev Helper method that sets the balance of an account on balanceAndBlacklistStates.
     * Since balances are stored in the last 255 bits of the balanceAndBlacklistStates value,
     * we need to ensure that the updated balance does not exceed (2^255 - 1).
     * Since blacklisted accounts' balances cannot be updated, the method will also
     * revert if the account is blacklisted
     * @param _account The address of the account.
     * @param _balance The new fiat token balance of the account (max: (2^255 - 1)).
     */
    function _setBalance(address _account, uint256 _balance) internal override {
        require(
            _balance <= ((1 << 255) - 1),
            "FiatTokenV2_2: Balance exceeds (2^255 - 1)"
        );
        require(
            !_isBlacklisted(_account),
            "FiatTokenV2_2: Account is blacklisted"
        );
        balanceAndBlacklistStates[_account] = _balance;
    }
    /**
     * @inheritdoc Blacklistable
     */
    function _isBlacklisted(address _account)
        internal
        override
        view
        returns (bool)
    {
        return balanceAndBlacklistStates[_account] >> 255 == 1;
    }
    /**
     * @dev Helper method to obtain the balance of an account. Since balances
     * are stored in the last 255 bits of the balanceAndBlacklistStates value,
     * we apply a ((1 << 255) - 1) bit bitmask with an AND operation on the
     * balanceAndBlacklistState to obtain the balance.
     * @param _account  The address of the account.
     * @return          The fiat token balance of the account.
     */
    function _balanceOf(address _account)
        internal
        override
        view
        returns (uint256)
    {
        return balanceAndBlacklistStates[_account] & ((1 << 255) - 1);
    }
    /**
     * @inheritdoc FiatTokenV1
     */
    function approve(address spender, uint256 value)
        external
        override
        whenNotPaused
        returns (bool)
    {
        _approve(msg.sender, spender, value);
        return true;
    }
    /**
     * @inheritdoc FiatTokenV2
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external override whenNotPaused {
        _permit(owner, spender, value, deadline, v, r, s);
    }
    /**
     * @inheritdoc FiatTokenV2
     */
    function increaseAllowance(address spender, uint256 increment)
        external
        override
        whenNotPaused
        returns (bool)
    {
        _increaseAllowance(msg.sender, spender, increment);
        return true;
    }
    /**
     * @inheritdoc FiatTokenV2
     */
    function decreaseAllowance(address spender, uint256 decrement)
        external
        override
        whenNotPaused
        returns (bool)
    {
        _decreaseAllowance(msg.sender, spender, decrement);
        return true;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    using Address for address;
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { FiatTokenV2 } from "./FiatTokenV2.sol";
// solhint-disable func-name-mixedcase
/**
 * @title FiatToken V2.1
 * @notice ERC20 Token backed by fiat reserves, version 2.1
 */
contract FiatTokenV2_1 is FiatTokenV2 {
    /**
     * @notice Initialize v2.1
     * @param lostAndFound  The address to which the locked funds are sent
     */
    function initializeV2_1(address lostAndFound) external {
        // solhint-disable-next-line reason-string
        require(_initializedVersion == 1);
        uint256 lockedAmount = _balanceOf(address(this));
        if (lockedAmount > 0) {
            _transfer(address(this), lostAndFound, lockedAmount);
        }
        _blacklist(address(this));
        _initializedVersion = 2;
    }
    /**
     * @notice Version string for the EIP712 domain separator
     * @return Version string
     */
    function version() external pure returns (string memory) {
        return "2";
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { FiatTokenV1_1 } from "../v1.1/FiatTokenV1_1.sol";
import { EIP712 } from "../util/EIP712.sol";
import { EIP3009 } from "./EIP3009.sol";
import { EIP2612 } from "./EIP2612.sol";
/**
 * @title FiatToken V2
 * @notice ERC20 Token backed by fiat reserves, version 2
 */
contract FiatTokenV2 is FiatTokenV1_1, EIP3009, EIP2612 {
    uint8 internal _initializedVersion;
    /**
     * @notice Initialize v2
     * @param newName   New token name
     */
    function initializeV2(string calldata newName) external {
        // solhint-disable-next-line reason-string
        require(initialized && _initializedVersion == 0);
        name = newName;
        _DEPRECATED_CACHED_DOMAIN_SEPARATOR = EIP712.makeDomainSeparator(
            newName,
            "2"
        );
        _initializedVersion = 1;
    }
    /**
     * @notice Increase the allowance by a given increment
     * @param spender   Spender's address
     * @param increment Amount of increase in allowance
     * @return True if successful
     */
    function increaseAllowance(address spender, uint256 increment)
        external
        virtual
        whenNotPaused
        notBlacklisted(msg.sender)
        notBlacklisted(spender)
        returns (bool)
    {
        _increaseAllowance(msg.sender, spender, increment);
        return true;
    }
    /**
     * @notice Decrease the allowance by a given decrement
     * @param spender   Spender's address
     * @param decrement Amount of decrease in allowance
     * @return True if successful
     */
    function decreaseAllowance(address spender, uint256 decrement)
        external
        virtual
        whenNotPaused
        notBlacklisted(msg.sender)
        notBlacklisted(spender)
        returns (bool)
    {
        _decreaseAllowance(msg.sender, spender, decrement);
        return true;
    }
    /**
     * @notice Execute a transfer with a signed authorization
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param v             v of the signature
     * @param r             r of the signature
     * @param s             s of the signature
     */
    function transferWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
        _transferWithAuthorization(
            from,
            to,
            value,
            validAfter,
            validBefore,
            nonce,
            v,
            r,
            s
        );
    }
    /**
     * @notice Receive a transfer with a signed authorization from the payer
     * @dev This has an additional check to ensure that the payee's address
     * matches the caller of this function to prevent front-running attacks.
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param v             v of the signature
     * @param r             r of the signature
     * @param s             s of the signature
     */
    function receiveWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
        _receiveWithAuthorization(
            from,
            to,
            value,
            validAfter,
            validBefore,
            nonce,
            v,
            r,
            s
        );
    }
    /**
     * @notice Attempt to cancel an authorization
     * @dev Works only if the authorization is not yet used.
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     * @param v             v of the signature
     * @param r             r of the signature
     * @param s             s of the signature
     */
    function cancelAuthorization(
        address authorizer,
        bytes32 nonce,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external whenNotPaused {
        _cancelAuthorization(authorizer, nonce, v, r, s);
    }
    /**
     * @notice Update allowance with a signed permit
     * @param owner       Token owner's address (Authorizer)
     * @param spender     Spender's address
     * @param value       Amount of allowance
     * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
     * @param v           v of the signature
     * @param r           r of the signature
     * @param s           s of the signature
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    )
        external
        virtual
        whenNotPaused
        notBlacklisted(owner)
        notBlacklisted(spender)
    {
        _permit(owner, spender, value, deadline, v, r, s);
    }
    /**
     * @dev Internal function to increase the allowance by a given increment
     * @param owner     Token owner's address
     * @param spender   Spender's address
     * @param increment Amount of increase
     */
    function _increaseAllowance(
        address owner,
        address spender,
        uint256 increment
    ) internal override {
        _approve(owner, spender, allowed[owner][spender].add(increment));
    }
    /**
     * @dev Internal function to decrease the allowance by a given decrement
     * @param owner     Token owner's address
     * @param spender   Spender's address
     * @param decrement Amount of decrease
     */
    function _decreaseAllowance(
        address owner,
        address spender,
        uint256 decrement
    ) internal override {
        _approve(
            owner,
            spender,
            allowed[owner][spender].sub(
                decrement,
                "ERC20: decreased allowance below zero"
            )
        );
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
// solhint-disable func-name-mixedcase
/**
 * @title EIP712 Domain
 */
contract EIP712Domain {
    // was originally DOMAIN_SEPARATOR
    // but that has been moved to a method so we can override it in V2_2+
    bytes32 internal _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
    /**
     * @notice Get the EIP712 Domain Separator.
     * @return The bytes32 EIP712 domain separator.
     */
    function DOMAIN_SEPARATOR() external view returns (bytes32) {
        return _domainSeparator();
    }
    /**
     * @dev Internal method to get the EIP712 Domain Separator.
     * @return The bytes32 EIP712 domain separator.
     */
    function _domainSeparator() internal virtual view returns (bytes32) {
        return _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
import { EIP712Domain } from "./EIP712Domain.sol";
import { SignatureChecker } from "../util/SignatureChecker.sol";
import { MessageHashUtils } from "../util/MessageHashUtils.sol";
/**
 * @title EIP-3009
 * @notice Provide internal implementation for gas-abstracted transfers
 * @dev Contracts that inherit from this must wrap these with publicly
 * accessible functions, optionally adding modifiers where necessary
 */
abstract contract EIP3009 is AbstractFiatTokenV2, EIP712Domain {
    // keccak256("TransferWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
    bytes32
        public constant TRANSFER_WITH_AUTHORIZATION_TYPEHASH = 0x7c7c6cdb67a18743f49ec6fa9b35f50d52ed05cbed4cc592e13b44501c1a2267;
    // keccak256("ReceiveWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
    bytes32
        public constant RECEIVE_WITH_AUTHORIZATION_TYPEHASH = 0xd099cc98ef71107a616c4f0f941f04c322d8e254fe26b3c6668db87aae413de8;
    // keccak256("CancelAuthorization(address authorizer,bytes32 nonce)")
    bytes32
        public constant CANCEL_AUTHORIZATION_TYPEHASH = 0x158b0a9edf7a828aad02f63cd515c68ef2f50ba807396f6d12842833a1597429;
    /**
     * @dev authorizer address => nonce => bool (true if nonce is used)
     */
    mapping(address => mapping(bytes32 => bool)) private _authorizationStates;
    event AuthorizationUsed(address indexed authorizer, bytes32 indexed nonce);
    event AuthorizationCanceled(
        address indexed authorizer,
        bytes32 indexed nonce
    );
    /**
     * @notice Returns the state of an authorization
     * @dev Nonces are randomly generated 32-byte data unique to the
     * authorizer's address
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     * @return True if the nonce is used
     */
    function authorizationState(address authorizer, bytes32 nonce)
        external
        view
        returns (bool)
    {
        return _authorizationStates[authorizer][nonce];
    }
    /**
     * @notice Execute a transfer with a signed authorization
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param v             v of the signature
     * @param r             r of the signature
     * @param s             s of the signature
     */
    function _transferWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        _transferWithAuthorization(
            from,
            to,
            value,
            validAfter,
            validBefore,
            nonce,
            abi.encodePacked(r, s, v)
        );
    }
    /**
     * @notice Execute a transfer with a signed authorization
     * @dev EOA wallet signatures should be packed in the order of r, s, v.
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
     */
    function _transferWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        bytes memory signature
    ) internal {
        _requireValidAuthorization(from, nonce, validAfter, validBefore);
        _requireValidSignature(
            from,
            keccak256(
                abi.encode(
                    TRANSFER_WITH_AUTHORIZATION_TYPEHASH,
                    from,
                    to,
                    value,
                    validAfter,
                    validBefore,
                    nonce
                )
            ),
            signature
        );
        _markAuthorizationAsUsed(from, nonce);
        _transfer(from, to, value);
    }
    /**
     * @notice Receive a transfer with a signed authorization from the payer
     * @dev This has an additional check to ensure that the payee's address
     * matches the caller of this function to prevent front-running attacks.
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param v             v of the signature
     * @param r             r of the signature
     * @param s             s of the signature
     */
    function _receiveWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        _receiveWithAuthorization(
            from,
            to,
            value,
            validAfter,
            validBefore,
            nonce,
            abi.encodePacked(r, s, v)
        );
    }
    /**
     * @notice Receive a transfer with a signed authorization from the payer
     * @dev This has an additional check to ensure that the payee's address
     * matches the caller of this function to prevent front-running attacks.
     * EOA wallet signatures should be packed in the order of r, s, v.
     * @param from          Payer's address (Authorizer)
     * @param to            Payee's address
     * @param value         Amount to be transferred
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     * @param nonce         Unique nonce
     * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
     */
    function _receiveWithAuthorization(
        address from,
        address to,
        uint256 value,
        uint256 validAfter,
        uint256 validBefore,
        bytes32 nonce,
        bytes memory signature
    ) internal {
        require(to == msg.sender, "FiatTokenV2: caller must be the payee");
        _requireValidAuthorization(from, nonce, validAfter, validBefore);
        _requireValidSignature(
            from,
            keccak256(
                abi.encode(
                    RECEIVE_WITH_AUTHORIZATION_TYPEHASH,
                    from,
                    to,
                    value,
                    validAfter,
                    validBefore,
                    nonce
                )
            ),
            signature
        );
        _markAuthorizationAsUsed(from, nonce);
        _transfer(from, to, value);
    }
    /**
     * @notice Attempt to cancel an authorization
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     * @param v             v of the signature
     * @param r             r of the signature
     * @param s             s of the signature
     */
    function _cancelAuthorization(
        address authorizer,
        bytes32 nonce,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        _cancelAuthorization(authorizer, nonce, abi.encodePacked(r, s, v));
    }
    /**
     * @notice Attempt to cancel an authorization
     * @dev EOA wallet signatures should be packed in the order of r, s, v.
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
     */
    function _cancelAuthorization(
        address authorizer,
        bytes32 nonce,
        bytes memory signature
    ) internal {
        _requireUnusedAuthorization(authorizer, nonce);
        _requireValidSignature(
            authorizer,
            keccak256(
                abi.encode(CANCEL_AUTHORIZATION_TYPEHASH, authorizer, nonce)
            ),
            signature
        );
        _authorizationStates[authorizer][nonce] = true;
        emit AuthorizationCanceled(authorizer, nonce);
    }
    /**
     * @notice Validates that signature against input data struct
     * @param signer        Signer's address
     * @param dataHash      Hash of encoded data struct
     * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
     */
    function _requireValidSignature(
        address signer,
        bytes32 dataHash,
        bytes memory signature
    ) private view {
        require(
            SignatureChecker.isValidSignatureNow(
                signer,
                MessageHashUtils.toTypedDataHash(_domainSeparator(), dataHash),
                signature
            ),
            "FiatTokenV2: invalid signature"
        );
    }
    /**
     * @notice Check that an authorization is unused
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     */
    function _requireUnusedAuthorization(address authorizer, bytes32 nonce)
        private
        view
    {
        require(
            !_authorizationStates[authorizer][nonce],
            "FiatTokenV2: authorization is used or canceled"
        );
    }
    /**
     * @notice Check that authorization is valid
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     * @param validAfter    The time after which this is valid (unix time)
     * @param validBefore   The time before which this is valid (unix time)
     */
    function _requireValidAuthorization(
        address authorizer,
        bytes32 nonce,
        uint256 validAfter,
        uint256 validBefore
    ) private view {
        require(
            now > validAfter,
            "FiatTokenV2: authorization is not yet valid"
        );
        require(now < validBefore, "FiatTokenV2: authorization is expired");
        _requireUnusedAuthorization(authorizer, nonce);
    }
    /**
     * @notice Mark an authorization as used
     * @param authorizer    Authorizer's address
     * @param nonce         Nonce of the authorization
     */
    function _markAuthorizationAsUsed(address authorizer, bytes32 nonce)
        private
    {
        _authorizationStates[authorizer][nonce] = true;
        emit AuthorizationUsed(authorizer, nonce);
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
import { EIP712Domain } from "./EIP712Domain.sol";
import { MessageHashUtils } from "../util/MessageHashUtils.sol";
import { SignatureChecker } from "../util/SignatureChecker.sol";
/**
 * @title EIP-2612
 * @notice Provide internal implementation for gas-abstracted approvals
 */
abstract contract EIP2612 is AbstractFiatTokenV2, EIP712Domain {
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")
    bytes32
        public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint256) private _permitNonces;
    /**
     * @notice Nonces for permit
     * @param owner Token owner's address (Authorizer)
     * @return Next nonce
     */
    function nonces(address owner) external view returns (uint256) {
        return _permitNonces[owner];
    }
    /**
     * @notice Verify a signed approval permit and execute if valid
     * @param owner     Token owner's address (Authorizer)
     * @param spender   Spender's address
     * @param value     Amount of allowance
     * @param deadline  The time at which the signature expires (unix time), or max uint256 value to signal no expiration
     * @param v         v of the signature
     * @param r         r of the signature
     * @param s         s of the signature
     */
    function _permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        _permit(owner, spender, value, deadline, abi.encodePacked(r, s, v));
    }
    /**
     * @notice Verify a signed approval permit and execute if valid
     * @dev EOA wallet signatures should be packed in the order of r, s, v.
     * @param owner      Token owner's address (Authorizer)
     * @param spender    Spender's address
     * @param value      Amount of allowance
     * @param deadline   The time at which the signature expires (unix time), or max uint256 value to signal no expiration
     * @param signature  Signature byte array signed by an EOA wallet or a contract wallet
     */
    function _permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        bytes memory signature
    ) internal {
        require(
            deadline == type(uint256).max || deadline >= now,
            "FiatTokenV2: permit is expired"
        );
        bytes32 typedDataHash = MessageHashUtils.toTypedDataHash(
            _domainSeparator(),
            keccak256(
                abi.encode(
                    PERMIT_TYPEHASH,
                    owner,
                    spender,
                    value,
                    _permitNonces[owner]++,
                    deadline
                )
            )
        );
        require(
            SignatureChecker.isValidSignatureNow(
                owner,
                typedDataHash,
                signature
            ),
            "EIP2612: invalid signature"
        );
        _approve(owner, spender, value);
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { AbstractFiatTokenV1 } from "../v1/AbstractFiatTokenV1.sol";
abstract contract AbstractFiatTokenV2 is AbstractFiatTokenV1 {
    function _increaseAllowance(
        address owner,
        address spender,
        uint256 increment
    ) internal virtual;
    function _decreaseAllowance(
        address owner,
        address spender,
        uint256 decrement
    ) internal virtual;
}
/**
 * SPDX-License-Identifier: MIT
 *
 * Copyright (c) 2016 Smart Contract Solutions, Inc.
 * Copyright (c) 2018-2020 CENTRE SECZ
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
pragma solidity 0.6.12;
import { Ownable } from "./Ownable.sol";
/**
 * @notice Base contract which allows children to implement an emergency stop
 * mechanism
 * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/feb665136c0dae9912e08397c1a21c4af3651ef3/contracts/lifecycle/Pausable.sol
 * Modifications:
 * 1. Added pauser role, switched pause/unpause to be onlyPauser (6/14/2018)
 * 2. Removed whenNotPause/whenPaused from pause/unpause (6/14/2018)
 * 3. Removed whenPaused (6/14/2018)
 * 4. Switches ownable library to use ZeppelinOS (7/12/18)
 * 5. Remove constructor (7/13/18)
 * 6. Reformat, conform to Solidity 0.6 syntax and add error messages (5/13/20)
 * 7. Make public functions external (5/27/20)
 */
contract Pausable is Ownable {
    event Pause();
    event Unpause();
    event PauserChanged(address indexed newAddress);
    address public pauser;
    bool public paused = false;
    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     */
    modifier whenNotPaused() {
        require(!paused, "Pausable: paused");
        _;
    }
    /**
     * @dev throws if called by any account other than the pauser
     */
    modifier onlyPauser() {
        require(msg.sender == pauser, "Pausable: caller is not the pauser");
        _;
    }
    /**
     * @dev called by the owner to pause, triggers stopped state
     */
    function pause() external onlyPauser {
        paused = true;
        emit Pause();
    }
    /**
     * @dev called by the owner to unpause, returns to normal state
     */
    function unpause() external onlyPauser {
        paused = false;
        emit Unpause();
    }
    /**
     * @notice Updates the pauser address.
     * @param _newPauser The address of the new pauser.
     */
    function updatePauser(address _newPauser) external onlyOwner {
        require(
            _newPauser != address(0),
            "Pausable: new pauser is the zero address"
        );
        pauser = _newPauser;
        emit PauserChanged(pauser);
    }
}
/**
 * SPDX-License-Identifier: MIT
 *
 * Copyright (c) 2018 zOS Global Limited.
 * Copyright (c) 2018-2020 CENTRE SECZ
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
pragma solidity 0.6.12;
/**
 * @notice The Ownable contract has an owner address, and provides basic
 * authorization control functions
 * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-labs/blob/3887ab77b8adafba4a26ace002f3a684c1a3388b/upgradeability_ownership/contracts/ownership/Ownable.sol
 * Modifications:
 * 1. Consolidate OwnableStorage into this contract (7/13/18)
 * 2. Reformat, conform to Solidity 0.6 syntax, and add error messages (5/13/20)
 * 3. Make public functions external (5/27/20)
 */
contract Ownable {
    // Owner of the contract
    address private _owner;
    /**
     * @dev Event to show ownership has been transferred
     * @param previousOwner representing the address of the previous owner
     * @param newOwner representing the address of the new owner
     */
    event OwnershipTransferred(address previousOwner, address newOwner);
    /**
     * @dev The constructor sets the original owner of the contract to the sender account.
     */
    constructor() public {
        setOwner(msg.sender);
    }
    /**
     * @dev Tells the address of the owner
     * @return the address of the owner
     */
    function owner() external view returns (address) {
        return _owner;
    }
    /**
     * @dev Sets a new owner address
     */
    function setOwner(address newOwner) internal {
        _owner = newOwner;
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(msg.sender == _owner, "Ownable: caller is not the owner");
        _;
    }
    /**
     * @dev Allows the current owner to transfer control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function transferOwnership(address newOwner) external onlyOwner {
        require(
            newOwner != address(0),
            "Ownable: new owner is the zero address"
        );
        emit OwnershipTransferred(_owner, newOwner);
        setOwner(newOwner);
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
import { AbstractFiatTokenV1 } from "./AbstractFiatTokenV1.sol";
import { Ownable } from "./Ownable.sol";
import { Pausable } from "./Pausable.sol";
import { Blacklistable } from "./Blacklistable.sol";
/**
 * @title FiatToken
 * @dev ERC20 Token backed by fiat reserves
 */
contract FiatTokenV1 is AbstractFiatTokenV1, Ownable, Pausable, Blacklistable {
    using SafeMath for uint256;
    string public name;
    string public symbol;
    uint8 public decimals;
    string public currency;
    address public masterMinter;
    bool internal initialized;
    /// @dev A mapping that stores the balance and blacklist states for a given address.
    /// The first bit defines whether the address is blacklisted (1 if blacklisted, 0 otherwise).
    /// The last 255 bits define the balance for the address.
    mapping(address => uint256) internal balanceAndBlacklistStates;
    mapping(address => mapping(address => uint256)) internal allowed;
    uint256 internal totalSupply_ = 0;
    mapping(address => bool) internal minters;
    mapping(address => uint256) internal minterAllowed;
    event Mint(address indexed minter, address indexed to, uint256 amount);
    event Burn(address indexed burner, uint256 amount);
    event MinterConfigured(address indexed minter, uint256 minterAllowedAmount);
    event MinterRemoved(address indexed oldMinter);
    event MasterMinterChanged(address indexed newMasterMinter);
    /**
     * @notice Initializes the fiat token contract.
     * @param tokenName       The name of the fiat token.
     * @param tokenSymbol     The symbol of the fiat token.
     * @param tokenCurrency   The fiat currency that the token represents.
     * @param tokenDecimals   The number of decimals that the token uses.
     * @param newMasterMinter The masterMinter address for the fiat token.
     * @param newPauser       The pauser address for the fiat token.
     * @param newBlacklister  The blacklister address for the fiat token.
     * @param newOwner        The owner of the fiat token.
     */
    function initialize(
        string memory tokenName,
        string memory tokenSymbol,
        string memory tokenCurrency,
        uint8 tokenDecimals,
        address newMasterMinter,
        address newPauser,
        address newBlacklister,
        address newOwner
    ) public {
        require(!initialized, "FiatToken: contract is already initialized");
        require(
            newMasterMinter != address(0),
            "FiatToken: new masterMinter is the zero address"
        );
        require(
            newPauser != address(0),
            "FiatToken: new pauser is the zero address"
        );
        require(
            newBlacklister != address(0),
            "FiatToken: new blacklister is the zero address"
        );
        require(
            newOwner != address(0),
            "FiatToken: new owner is the zero address"
        );
        name = tokenName;
        symbol = tokenSymbol;
        currency = tokenCurrency;
        decimals = tokenDecimals;
        masterMinter = newMasterMinter;
        pauser = newPauser;
        blacklister = newBlacklister;
        setOwner(newOwner);
        initialized = true;
    }
    /**
     * @dev Throws if called by any account other than a minter.
     */
    modifier onlyMinters() {
        require(minters[msg.sender], "FiatToken: caller is not a minter");
        _;
    }
    /**
     * @notice Mints fiat tokens to an address.
     * @param _to The address that will receive the minted tokens.
     * @param _amount The amount of tokens to mint. Must be less than or equal
     * to the minterAllowance of the caller.
     * @return True if the operation was successful.
     */
    function mint(address _to, uint256 _amount)
        external
        whenNotPaused
        onlyMinters
        notBlacklisted(msg.sender)
        notBlacklisted(_to)
        returns (bool)
    {
        require(_to != address(0), "FiatToken: mint to the zero address");
        require(_amount > 0, "FiatToken: mint amount not greater than 0");
        uint256 mintingAllowedAmount = minterAllowed[msg.sender];
        require(
            _amount <= mintingAllowedAmount,
            "FiatToken: mint amount exceeds minterAllowance"
        );
        totalSupply_ = totalSupply_.add(_amount);
        _setBalance(_to, _balanceOf(_to).add(_amount));
        minterAllowed[msg.sender] = mintingAllowedAmount.sub(_amount);
        emit Mint(msg.sender, _to, _amount);
        emit Transfer(address(0), _to, _amount);
        return true;
    }
    /**
     * @dev Throws if called by any account other than the masterMinter
     */
    modifier onlyMasterMinter() {
        require(
            msg.sender == masterMinter,
            "FiatToken: caller is not the masterMinter"
        );
        _;
    }
    /**
     * @notice Gets the minter allowance for an account.
     * @param minter The address to check.
     * @return The remaining minter allowance for the account.
     */
    function minterAllowance(address minter) external view returns (uint256) {
        return minterAllowed[minter];
    }
    /**
     * @notice Checks if an account is a minter.
     * @param account The address to check.
     * @return True if the account is a minter, false if the account is not a minter.
     */
    function isMinter(address account) external view returns (bool) {
        return minters[account];
    }
    /**
     * @notice Gets the remaining amount of fiat tokens a spender is allowed to transfer on
     * behalf of the token owner.
     * @param owner   The token owner's address.
     * @param spender The spender's address.
     * @return The remaining allowance.
     */
    function allowance(address owner, address spender)
        external
        override
        view
        returns (uint256)
    {
        return allowed[owner][spender];
    }
    /**
     * @notice Gets the totalSupply of the fiat token.
     * @return The totalSupply of the fiat token.
     */
    function totalSupply() external override view returns (uint256) {
        return totalSupply_;
    }
    /**
     * @notice Gets the fiat token balance of an account.
     * @param account  The address to check.
     * @return balance The fiat token balance of the account.
     */
    function balanceOf(address account)
        external
        override
        view
        returns (uint256)
    {
        return _balanceOf(account);
    }
    /**
     * @notice Sets a fiat token allowance for a spender to spend on behalf of the caller.
     * @param spender The spender's address.
     * @param value   The allowance amount.
     * @return True if the operation was successful.
     */
    function approve(address spender, uint256 value)
        external
        virtual
        override
        whenNotPaused
        notBlacklisted(msg.sender)
        notBlacklisted(spender)
        returns (bool)
    {
        _approve(msg.sender, spender, value);
        return true;
    }
    /**
     * @dev Internal function to set allowance.
     * @param owner     Token owner's address.
     * @param spender   Spender's address.
     * @param value     Allowance amount.
     */
    function _approve(
        address owner,
        address spender,
        uint256 value
    ) internal override {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        allowed[owner][spender] = value;
        emit Approval(owner, spender, value);
    }
    /**
     * @notice Transfers tokens from an address to another by spending the caller's allowance.
     * @dev The caller must have some fiat token allowance on the payer's tokens.
     * @param from  Payer's address.
     * @param to    Payee's address.
     * @param value Transfer amount.
     * @return True if the operation was successful.
     */
    function transferFrom(
        address from,
        address to,
        uint256 value
    )
        external
        override
        whenNotPaused
        notBlacklisted(msg.sender)
        notBlacklisted(from)
        notBlacklisted(to)
        returns (bool)
    {
        require(
            value <= allowed[from][msg.sender],
            "ERC20: transfer amount exceeds allowance"
        );
        _transfer(from, to, value);
        allowed[from][msg.sender] = allowed[from][msg.sender].sub(value);
        return true;
    }
    /**
     * @notice Transfers tokens from the caller.
     * @param to    Payee's address.
     * @param value Transfer amount.
     * @return True if the operation was successful.
     */
    function transfer(address to, uint256 value)
        external
        override
        whenNotPaused
        notBlacklisted(msg.sender)
        notBlacklisted(to)
        returns (bool)
    {
        _transfer(msg.sender, to, value);
        return true;
    }
    /**
     * @dev Internal function to process transfers.
     * @param from  Payer's address.
     * @param to    Payee's address.
     * @param value Transfer amount.
     */
    function _transfer(
        address from,
        address to,
        uint256 value
    ) internal override {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        require(
            value <= _balanceOf(from),
            "ERC20: transfer amount exceeds balance"
        );
        _setBalance(from, _balanceOf(from).sub(value));
        _setBalance(to, _balanceOf(to).add(value));
        emit Transfer(from, to, value);
    }
    /**
     * @notice Adds or updates a new minter with a mint allowance.
     * @param minter The address of the minter.
     * @param minterAllowedAmount The minting amount allowed for the minter.
     * @return True if the operation was successful.
     */
    function configureMinter(address minter, uint256 minterAllowedAmount)
        external
        whenNotPaused
        onlyMasterMinter
        returns (bool)
    {
        minters[minter] = true;
        minterAllowed[minter] = minterAllowedAmount;
        emit MinterConfigured(minter, minterAllowedAmount);
        return true;
    }
    /**
     * @notice Removes a minter.
     * @param minter The address of the minter to remove.
     * @return True if the operation was successful.
     */
    function removeMinter(address minter)
        external
        onlyMasterMinter
        returns (bool)
    {
        minters[minter] = false;
        minterAllowed[minter] = 0;
        emit MinterRemoved(minter);
        return true;
    }
    /**
     * @notice Allows a minter to burn some of its own tokens.
     * @dev The caller must be a minter, must not be blacklisted, and the amount to burn
     * should be less than or equal to the account's balance.
     * @param _amount the amount of tokens to be burned.
     */
    function burn(uint256 _amount)
        external
        whenNotPaused
        onlyMinters
        notBlacklisted(msg.sender)
    {
        uint256 balance = _balanceOf(msg.sender);
        require(_amount > 0, "FiatToken: burn amount not greater than 0");
        require(balance >= _amount, "FiatToken: burn amount exceeds balance");
        totalSupply_ = totalSupply_.sub(_amount);
        _setBalance(msg.sender, balance.sub(_amount));
        emit Burn(msg.sender, _amount);
        emit Transfer(msg.sender, address(0), _amount);
    }
    /**
     * @notice Updates the master minter address.
     * @param _newMasterMinter The address of the new master minter.
     */
    function updateMasterMinter(address _newMasterMinter) external onlyOwner {
        require(
            _newMasterMinter != address(0),
            "FiatToken: new masterMinter is the zero address"
        );
        masterMinter = _newMasterMinter;
        emit MasterMinterChanged(masterMinter);
    }
    /**
     * @inheritdoc Blacklistable
     */
    function _blacklist(address _account) internal override {
        _setBlacklistState(_account, true);
    }
    /**
     * @inheritdoc Blacklistable
     */
    function _unBlacklist(address _account) internal override {
        _setBlacklistState(_account, false);
    }
    /**
     * @dev Helper method that sets the blacklist state of an account.
     * @param _account         The address of the account.
     * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
     */
    function _setBlacklistState(address _account, bool _shouldBlacklist)
        internal
        virtual
    {
        _deprecatedBlacklisted[_account] = _shouldBlacklist;
    }
    /**
     * @dev Helper method that sets the balance of an account.
     * @param _account The address of the account.
     * @param _balance The new fiat token balance of the account.
     */
    function _setBalance(address _account, uint256 _balance) internal virtual {
        balanceAndBlacklistStates[_account] = _balance;
    }
    /**
     * @inheritdoc Blacklistable
     */
    function _isBlacklisted(address _account)
        internal
        virtual
        override
        view
        returns (bool)
    {
        return _deprecatedBlacklisted[_account];
    }
    /**
     * @dev Helper method to obtain the balance of an account.
     * @param _account  The address of the account.
     * @return          The fiat token balance of the account.
     */
    function _balanceOf(address _account)
        internal
        virtual
        view
        returns (uint256)
    {
        return balanceAndBlacklistStates[_account];
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { Ownable } from "./Ownable.sol";
/**
 * @title Blacklistable Token
 * @dev Allows accounts to be blacklisted by a "blacklister" role
 */
abstract contract Blacklistable is Ownable {
    address public blacklister;
    mapping(address => bool) internal _deprecatedBlacklisted;
    event Blacklisted(address indexed _account);
    event UnBlacklisted(address indexed _account);
    event BlacklisterChanged(address indexed newBlacklister);
    /**
     * @dev Throws if called by any account other than the blacklister.
     */
    modifier onlyBlacklister() {
        require(
            msg.sender == blacklister,
            "Blacklistable: caller is not the blacklister"
        );
        _;
    }
    /**
     * @dev Throws if argument account is blacklisted.
     * @param _account The address to check.
     */
    modifier notBlacklisted(address _account) {
        require(
            !_isBlacklisted(_account),
            "Blacklistable: account is blacklisted"
        );
        _;
    }
    /**
     * @notice Checks if account is blacklisted.
     * @param _account The address to check.
     * @return True if the account is blacklisted, false if the account is not blacklisted.
     */
    function isBlacklisted(address _account) external view returns (bool) {
        return _isBlacklisted(_account);
    }
    /**
     * @notice Adds account to blacklist.
     * @param _account The address to blacklist.
     */
    function blacklist(address _account) external onlyBlacklister {
        _blacklist(_account);
        emit Blacklisted(_account);
    }
    /**
     * @notice Removes account from blacklist.
     * @param _account The address to remove from the blacklist.
     */
    function unBlacklist(address _account) external onlyBlacklister {
        _unBlacklist(_account);
        emit UnBlacklisted(_account);
    }
    /**
     * @notice Updates the blacklister address.
     * @param _newBlacklister The address of the new blacklister.
     */
    function updateBlacklister(address _newBlacklister) external onlyOwner {
        require(
            _newBlacklister != address(0),
            "Blacklistable: new blacklister is the zero address"
        );
        blacklister = _newBlacklister;
        emit BlacklisterChanged(blacklister);
    }
    /**
     * @dev Checks if account is blacklisted.
     * @param _account The address to check.
     * @return true if the account is blacklisted, false otherwise.
     */
    function _isBlacklisted(address _account)
        internal
        virtual
        view
        returns (bool);
    /**
     * @dev Helper method that blacklists an account.
     * @param _account The address to blacklist.
     */
    function _blacklist(address _account) internal virtual;
    /**
     * @dev Helper method that unblacklists an account.
     * @param _account The address to unblacklist.
     */
    function _unBlacklist(address _account) internal virtual;
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
abstract contract AbstractFiatTokenV1 is IERC20 {
    function _approve(
        address owner,
        address spender,
        uint256 value
    ) internal virtual;
    function _transfer(
        address from,
        address to,
        uint256 value
    ) internal virtual;
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { Ownable } from "../v1/Ownable.sol";
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
contract Rescuable is Ownable {
    using SafeERC20 for IERC20;
    address private _rescuer;
    event RescuerChanged(address indexed newRescuer);
    /**
     * @notice Returns current rescuer
     * @return Rescuer's address
     */
    function rescuer() external view returns (address) {
        return _rescuer;
    }
    /**
     * @notice Revert if called by any account other than the rescuer.
     */
    modifier onlyRescuer() {
        require(msg.sender == _rescuer, "Rescuable: caller is not the rescuer");
        _;
    }
    /**
     * @notice Rescue ERC20 tokens locked up in this contract.
     * @param tokenContract ERC20 token contract address
     * @param to        Recipient address
     * @param amount    Amount to withdraw
     */
    function rescueERC20(
        IERC20 tokenContract,
        address to,
        uint256 amount
    ) external onlyRescuer {
        tokenContract.safeTransfer(to, amount);
    }
    /**
     * @notice Updates the rescuer address.
     * @param newRescuer The address of the new rescuer.
     */
    function updateRescuer(address newRescuer) external onlyOwner {
        require(
            newRescuer != address(0),
            "Rescuable: new rescuer is the zero address"
        );
        _rescuer = newRescuer;
        emit RescuerChanged(newRescuer);
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { FiatTokenV1 } from "../v1/FiatTokenV1.sol";
import { Rescuable } from "./Rescuable.sol";
/**
 * @title FiatTokenV1_1
 * @dev ERC20 Token backed by fiat reserves
 */
contract FiatTokenV1_1 is FiatTokenV1, Rescuable {
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
import { ECRecover } from "./ECRecover.sol";
import { IERC1271 } from "../interface/IERC1271.sol";
/**
 * @dev Signature verification helper that can be used instead of `ECRecover.recover` to seamlessly support both ECDSA
 * signatures from externally owned accounts (EOAs) as well as ERC1271 signatures from smart contract wallets.
 *
 * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/SignatureChecker.sol
 */
library SignatureChecker {
    /**
     * @dev Checks if a signature is valid for a given signer and data hash. If the signer is a smart contract, the
     * signature is validated against that smart contract using ERC1271, otherwise it's validated using `ECRecover.recover`.
     * @param signer        Address of the claimed signer
     * @param digest        Keccak-256 hash digest of the signed message
     * @param signature     Signature byte array associated with hash
     */
    function isValidSignatureNow(
        address signer,
        bytes32 digest,
        bytes memory signature
    ) external view returns (bool) {
        if (!isContract(signer)) {
            return ECRecover.recover(digest, signature) == signer;
        }
        return isValidERC1271SignatureNow(signer, digest, signature);
    }
    /**
     * @dev Checks if a signature is valid for a given signer and data hash. The signature is validated
     * against the signer smart contract using ERC1271.
     * @param signer        Address of the claimed signer
     * @param digest        Keccak-256 hash digest of the signed message
     * @param signature     Signature byte array associated with hash
     *
     * NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
     * change through time. It could return true at block N and false at block N+1 (or the opposite).
     */
    function isValidERC1271SignatureNow(
        address signer,
        bytes32 digest,
        bytes memory signature
    ) internal view returns (bool) {
        (bool success, bytes memory result) = signer.staticcall(
            abi.encodeWithSelector(
                IERC1271.isValidSignature.selector,
                digest,
                signature
            )
        );
        return (success &&
            result.length >= 32 &&
            abi.decode(result, (bytes32)) ==
            bytes32(IERC1271.isValidSignature.selector));
    }
    /**
     * @dev Checks if the input address is a smart contract.
     */
    function isContract(address addr) internal view returns (bool) {
        uint256 size;
        assembly {
            size := extcodesize(addr)
        }
        return size > 0;
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
/**
 * @dev Signature message hash utilities for producing digests to be consumed by {ECDSA} recovery or signing.
 *
 * The library provides methods for generating a hash of a message that conforms to the
 * https://eips.ethereum.org/EIPS/eip-191[EIP 191] and https://eips.ethereum.org/EIPS/eip-712[EIP 712]
 * specifications.
 */
library MessageHashUtils {
    /**
     * @dev Returns the keccak256 digest of an EIP-712 typed data (EIP-191 version `0x01`).
     * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/MessageHashUtils.sol
     *
     * The digest is calculated from a `domainSeparator` and a `structHash`, by prefixing them with
     * `\\x19\\x01` and hashing the result. It corresponds to the hash signed by the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] JSON-RPC method as part of EIP-712.
     *
     * @param domainSeparator    Domain separator
     * @param structHash         Hashed EIP-712 data struct
     * @return digest            The keccak256 digest of an EIP-712 typed data
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash)
        internal
        pure
        returns (bytes32 digest)
    {
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, "\\x19\\x01")
            mstore(add(ptr, 0x02), domainSeparator)
            mstore(add(ptr, 0x22), structHash)
            digest := keccak256(ptr, 0x42)
        }
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
/**
 * @title EIP712
 * @notice A library that provides EIP712 helper functions
 */
library EIP712 {
    /**
     * @notice Make EIP712 domain separator
     * @param name      Contract name
     * @param version   Contract version
     * @param chainId   Blockchain ID
     * @return Domain separator
     */
    function makeDomainSeparator(
        string memory name,
        string memory version,
        uint256 chainId
    ) internal view returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                    0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f,
                    keccak256(bytes(name)),
                    keccak256(bytes(version)),
                    chainId,
                    address(this)
                )
            );
    }
    /**
     * @notice Make EIP712 domain separator
     * @param name      Contract name
     * @param version   Contract version
     * @return Domain separator
     */
    function makeDomainSeparator(string memory name, string memory version)
        internal
        view
        returns (bytes32)
    {
        uint256 chainId;
        assembly {
            chainId := chainid()
        }
        return makeDomainSeparator(name, version, chainId);
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
/**
 * @title ECRecover
 * @notice A library that provides a safe ECDSA recovery function
 */
library ECRecover {
    /**
     * @notice Recover signer's address from a signed message
     * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/65e4ffde586ec89af3b7e9140bdc9235d1254853/contracts/cryptography/ECDSA.sol
     * Modifications: Accept v, r, and s as separate arguments
     * @param digest    Keccak-256 hash digest of the signed message
     * @param v         v of the signature
     * @param r         r of the signature
     * @param s         s of the signature
     * @return Signer address
     */
    function recover(
        bytes32 digest,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address) {
        // 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 (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): 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
        ) {
            revert("ECRecover: invalid signature 's' value");
        }
        if (v != 27 && v != 28) {
            revert("ECRecover: invalid signature 'v' value");
        }
        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(digest, v, r, s);
        require(signer != address(0), "ECRecover: invalid signature");
        return signer;
    }
    /**
     * @notice Recover signer's address from a signed message
     * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/0053ee040a7ff1dbc39691c9e67a69f564930a88/contracts/utils/cryptography/ECDSA.sol
     * @param digest    Keccak-256 hash digest of the signed message
     * @param signature Signature byte array associated with hash
     * @return Signer address
     */
    function recover(bytes32 digest, bytes memory signature)
        internal
        pure
        returns (address)
    {
        require(signature.length == 65, "ECRecover: invalid signature length");
        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 recover(digest, v, r, s);
    }
}
/**
 * SPDX-License-Identifier: Apache-2.0
 *
 * Copyright (c) 2023, Circle Internet Financial, LLC.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
pragma solidity 0.6.12;
/**
 * @dev Interface of the ERC1271 standard signature validation method for
 * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
 */
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 the provided data hash
     * @return magicValue   bytes4 magic value 0x1626ba7e when function passes
     */
    function isValidSignature(bytes32 hash, bytes memory signature)
        external
        view
        returns (bytes4 magicValue);
}