// File: contracts/SafeFarm.sol



//SPDX-License-Identifier: Unlicense
pragma solidity 0.8.7;

import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/access/AccessControl.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

import "./UniswapInterfaces.sol";

/**
 * @dev Implementation of a SafeFarm contract to deposit funds for yield optimizing.
 * This is the contract that receives funds and that users interface with.
 * The yield optimizing strategy itself is implemented in a separate 'Strategy.sol' contract.
 */
contract SafeFarm is ReentrancyGuard, AccessControl {
    using SafeERC20 for IERC20;

    bytes32 public constant ORACLE_ROLE = keccak256("ORACLE_ROLE");

    struct LPToken {
      uint256 amount;
      address token;
    }

    // The strategy currently in use by the vault.
    IStrategy public strategy;
    IVault public vault;

    // Events
    event UpgradeStrat(address newStrategy);

    event Deposit(address indexed account, uint256 shares);
    event Withdraw(address indexed account, uint256 shares);
    event SafeSwap(address indexed account, uint256 shares);
    event Earn(uint256 amount);

    /**
     * @dev Sets the strategy of yield optimizing and initialize the admin account.
     * @param _strategy the address of the strategy.
     */
    constructor (
        address _strategy
    ) {
        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);

        strategy = IStrategy(_strategy);

        emit UpgradeStrat(_strategy);
    }

    /**
     * @notice Strict access by admin role
     */
    modifier onlyAdmin() {
        require(hasRole(DEFAULT_ADMIN_ROLE, msg.sender), "sender doesn't have admin role");
        _;
    }

    /**
     * @notice Strict access by safe farming oracle role
     */
    modifier onlySFOracle() {
        require(hasRole(ORACLE_ROLE, msg.sender), "sender doesn't have oracle role");
        _;
    }

    /**
     * @notice Removes admin role from {msg.sender} and grants it to {newAdmin}.
     * @notice Only callable by an address that currently has the admin role.
     * @param newAdmin Address that admin role will be granted to.
    */
    function renounceAdmin(address newAdmin) external onlyAdmin {
        grantRole(DEFAULT_ADMIN_ROLE, newAdmin);
        renounceRole(DEFAULT_ADMIN_ROLE, msg.sender);
    }

    /**
     * @notice Grants {oracleAddress} the relayer role and increases {_totalOracles} count.
     * @notice Only callable by an address that currently has the admin role.
     * @param oracleAddress Address of safe farm to be added.
    */
    function adminAddOracle(address oracleAddress) external onlyAdmin {
        require(!hasRole(ORACLE_ROLE, oracleAddress), "addr already has oracle role!");
        grantRole(ORACLE_ROLE, oracleAddress);
    }

    /**
     * @notice Removes oracle role for {oracleAddress} and decreases {_totalOracles} count.
     * @notice Only callable by an address that currently has the admin role.
     * @param oracleAddress Address of safe farm to be removed.
    */
    function adminRemoveOracle(address oracleAddress) external onlyAdmin {
        require(hasRole(ORACLE_ROLE, oracleAddress), "addr doesn't have oracle role!");
        revokeRole(ORACLE_ROLE, oracleAddress);
    }

    /**
     * @notice Initialize vault address.
     * @notice Only callable by an address that currently has the admin role.
     * @param _vault Address of vault contract.
    */
    function initVault(address _vault) external onlyAdmin {
        require(address(vault) == address(0), "vault already inited");
        require(_vault != address(0), "empty vault");

        vault = IVault(_vault);
    }

    /**
     * @dev It switches the active strat for the new strat candidate.
     * @param _newStrategy Address of new strategy contract.
     */
    function upgradeStrat(address _newStrategy) external onlyAdmin {
        require(_newStrategy != address(0), "There is no candidate");
        require(strategy.want() == IStrategy(_newStrategy).want(), "Want Token doesn't same");

        IStrategy prevStrategy = strategy;
        strategy = IStrategy(_newStrategy);

        prevStrategy.retireStrat();

        earn();

        emit UpgradeStrat(_newStrategy);
    }

    /**
     * @dev Rescues random funds stuck that the strat can't handle.
     * @param _token address of the token to rescue.
     */
    function inCaseTokensGetStuck(address _token) external onlyAdmin {
        require(_token != address(want()), "!token");

        uint256 amount = IERC20(_token).balanceOf(address(this));
        IERC20(_token).safeTransfer(msg.sender, amount);
    }


    /**
     * @notice A migration function to the new SafeFarm contract
     * @dev Funds will be moved to new contract.
     * @dev Only callable by vault contract
     * @param newSafeFarm Address of new SafeFarm contract.
    */
    function migrate(address newSafeFarm) external {
        require(msg.sender == address(vault), "!vault");

        uint256 amount = available();
        if (amount > 0) {
            want().safeTransfer(newSafeFarm, amount);
        }

        strategy.migrate(newSafeFarm);
    }



    /**
     * @dev Function for various UIs to display the current value of one of our yield tokens.
     * Returns an uint256 with 18 decimals of how much underlying asset one vault share represents.
     */
    function getPricePerFullShare() external view returns (uint256) {
        uint256 totalSupply = vault.totalSupply();
        return totalSupply == 0 ? 1e18 : (balance() * 1e18 / totalSupply);
    }

    /**
     * @dev A helper function to call deposit() with all the sender's funds.
     */
    function depositAll(uint256 _amountOutMin) external {
        deposit(want().balanceOf(msg.sender), _amountOutMin);
    }

    /**
     * @dev A helper function to call deposit() with all the sender's funds.
     * @param route Swap route
     */
    function depositAll(address[] memory route, uint256 _amountOutMin) external {
        IERC20 tokenA = IERC20(route[0]);
        deposit(tokenA.balanceOf(msg.sender), route, _amountOutMin);
    }


    /**
     * @dev A helper function to call withdraw() with all the sender's funds.
     */
    function withdrawAll() external {
        withdraw(vault.balanceOf(msg.sender));
    }

    /**
     * @dev The entrypoint of safe swap from the system by oracle.
     * @param _account Address of account
     * @param _percent Percent of funds
     * @param _fee Additional fee amount for gas compensation
     * @param _route Swap route
     */
    function safeSwap(
        address _account, uint256 _percent,
        uint256 _fee,
        address[] memory _route
    ) external onlySFOracle {
        uint256 shares = calcShares(_account, _percent);
        uint256 totalShares = vault.totalSupply();
        vault.burn(_account, shares);
        strategy.safeSwap(_account, shares, totalShares, _fee, _route);

        emit SafeSwap(_account, shares);
    }


    /**
     * @dev The entrypoint of safe swap from the system by oracle with multi routes.
     * @param _account Address of account
     * @param _percent Percent of funds
     * @param _fee Additional fee amount for gas compensation
     * @param _route0 Swap route
     * @param _route1 Second swap route
     */
    function safeSwap(
        address _account, uint256 _percent,
        uint256 _fee,
        address[] memory _route0, address[] memory _route1
    ) external onlySFOracle {
        uint256 shares = calcShares(_account, _percent);
        uint256 totalShares = vault.totalSupply();
        vault.burn(_account, shares);
        strategy.safeSwap(_account, shares, totalShares, _fee, _route0, _route1);

        emit SafeSwap(_account, shares);
    }


    /**
     * @dev The entrypoint of funds into the system. People deposit with this function
     * into the vault. The vault is then in charge of sending funds into the strategy.
     * @param _amount Amount of funds
     */
    function deposit(uint256 _amount, uint256 _amountOutMin) public nonReentrant {
        address[] memory route = new address[](1);
        route[0] = strategy.want();
        _deposit(msg.sender, _amount, 0, route, _amountOutMin);
    }

    /**
     * @dev The entrypoint of funds into the system. People deposit with this function
     * into the vault. The vault is then in charge of sending funds into the strategy.
     * @param _amount Amount of funds
     * @param route Swap route
     * @param _amountOutMin Minimum swap amount
     */
    function deposit(uint256 _amount, address[] memory route,
        uint256 _amountOutMin
    ) public nonReentrant {
        _deposit(msg.sender, _amount, 0, route, _amountOutMin);
    }

    /**
     * @dev The entrypoint of funds into the system. People deposit with this function
     * into the vault. The vault is then in charge of sending funds into the strategy.
     * @param _amount Amount of funds
     * @param route0 Swap route to lpToken0
     * @param route1 Swap route to lpToken1
     * @param _amountOutMin Minimum amounts for swap by routes and addLiquidity
     *   _amountOutMin[0] - min swap amount by route0
     *   _amountOutMin[1] - min swap amount by route1
     *   _amountOutMin[2] - amountAMin for addLiquidity lpToken
     *   _amountOutMin[3] - amountBMin for addLiquidity lpToken
     */
    function depositLP(uint256 _amount,
        address[] memory route0, address[] memory route1,
        uint256[] memory _amountOutMin
    ) external nonReentrant {
        _depositLP(msg.sender, _amount, 0, route0, route1,
            _amountOutMin
        );
    }


    /**
     * @dev Function to exit the system. The vault will withdraw the required tokens
     * from the strategy and pay up the token holder. A proportional number of IOU
     * tokens are burned in the process.
     */
    function withdraw(uint256 _shares) public nonReentrant {
        uint256 totalShares = vault.totalSupply();
        vault.burn(msg.sender, _shares);
        strategy.withdraw(msg.sender, _shares, totalShares);

        emit Withdraw(msg.sender, _shares);
    }

    /**
     * @dev The entrypoint of auto funds into the system by oracle.
     * @param from Address of account
     * @param _amount Amount of funds
     * @param _fee Additional fee amount for gas compensation
     * @param route Swap route
     * @param _amountOutMin Minimum swap out amount
     */
    function depositAuto(
        address from,
        uint256 _amount,
        uint256 _fee,
        address[] memory route,
        uint256 _amountOutMin
    ) external onlySFOracle {
        _fee+= strategy.safeFarmFeeAmount(_amount);

        _deposit(from, _amount, _fee, route, _amountOutMin);
    }

    /**
     * @dev The entrypoint of auto funds into the system by oracle.
     * @param from Address of account
     * @param _amount Amount of funds
     * @param _fee Additional fee amount for gas compensation
     * @param route0 Swap route to lpToken0
     * @param route1 Swap route to lpToken1
     * @param _amountOutMin min amounts for swap by routes and addLiquidity
     *   _amountOutMin[0] - min swap amount by route0
     *   _amountOutMin[1] - min swap amount by route1
     *   _amountOutMin[2] - amountAMin for addLiquidity lpToken
     *   _amountOutMin[3] - amountBMin for addLiquidity lpToken
     */
    function depositAutoLP(
        address from,
        uint256 _amount,
        uint256 _fee,
        address[] memory route0, address[] memory route1,
        uint256[] memory _amountOutMin
    ) external onlySFOracle {
        _fee+= strategy.safeFarmFeeAmount(_amount);

        _depositLP(from, _amount, _fee, route0, route1, _amountOutMin);
    }


    // it calculates account shares by percent
    function calcShares(
        address _account, uint256 _percent
    ) public view returns (uint256 shares) {
        shares = vault.balanceOf(_account) * _percent / 100;
        return shares;
    }

    function want() public view returns (IERC20) {
        return IERC20(strategy.want());
    }

    /**
     * @dev It calculates the total underlying value of {token} held by the system.
     * It takes into account the vault contract balance, the strategy contract balance
     *  and the balance deployed in other contracts as part of the strategy.
     */
    function balance() public view returns (uint256) {
        return available() + strategy.balanceOf();
    }


    /**
     * @dev Custom logic in here for how much the contract allows to be borrowed.
     * We return 100% of tokens for now. Under certain conditions we might
     * want to keep some of the system funds at hand in the vault, instead
     * of putting them to work.
     */
    function available() public view returns (uint256) {
        return want().balanceOf(address(this));
    }


    /**
     * @dev The entrypoint of funds into the system. People deposit with this function
     * into the vault. The vault is then in charge of sending funds into the strategy.
     */
    function _deposit(
        address _depositor,
        uint256 _amount,
        uint256 _fee,
        address[] memory route,
        uint256 _amountOutMin
    ) internal {
        IERC20 tokenA = IERC20(route[0]);
        address tokenB = route[route.length - 1];
        require(tokenB == strategy.want(), 'invalid route');

        strategy.harvest();
        uint256 _before = balance();

        _amount = _receiveDeposit(tokenA, _depositor, _amount, _fee);

        if (route.length > 1) {
            address unirouter = strategy.unirouter();
            if (tokenA.allowance(address(this), unirouter) < _amount) {
                tokenA.safeApprove(unirouter, type(uint256).max);
            }

            uint256[] memory amounts = IUniswapRouterETH(unirouter).swapExactTokensForTokens(
                _amount,
                _amountOutMin,
                route,
                address(this),
                block.timestamp
            );

            _amount = amounts[amounts.length - 1];
        }

        earn();

        uint256 _after = strategy.balanceOfPool();
        uint256 shares = _after - _before; // Additional check for deflationary tokens
        if (shares > _amount) {
            shares = _amount;
        }

        uint256 totalSupply = vault.totalSupply();
        if (totalSupply > 0) {
            shares = (shares * totalSupply / _before);
        }

        require(shares > 0, 'ZERRO ST');

        vault.mint(_depositor, shares);

        emit Deposit(_depositor, shares);
    }

    function _depositLP(
        address _depositor,
        uint256 _amount,
        uint256 _fee,
        address[] memory _route0, address[] memory _route1,
        uint256[] memory _amountOutMin
    ) internal {
        require(_amountOutMin.length == 4, 'invalid _amountOutMin');

        IERC20 tokenA = IERC20(_checkRoutesLP(_route0, _route1));

        _amount = _receiveDeposit(tokenA, _depositor, _amount, _fee);

        address unirouter = strategy.unirouter();

        if (tokenA.allowance(address(this), unirouter) < _amount) {
            tokenA.safeApprove(unirouter, type(uint256).max);
        }

        uint256 amountHalf = _amount / 2;

        LPToken memory lpt0 = _swapLPToken(unirouter, amountHalf, _route0, _amountOutMin[0]);
        LPToken memory lpt1 = _swapLPToken(unirouter, (_amount - amountHalf), _route1, _amountOutMin[1]);

        strategy.harvest();
        uint256 _pool = balance();

        _amount = _addLpLiquidity(_depositor, unirouter, lpt0, lpt1, _amountOutMin);

        earn();

        uint256 shares = (strategy.balanceOfPool() - _pool); // Additional check for deflationary tokens
        if (shares > _amount) {
            shares = _amount;
        }

        uint256 totalSupply = vault.totalSupply();
        if (totalSupply > 0) {
            shares = (shares * totalSupply / _pool);
        }

        require(shares > 0, 'ZERRO ST');

        vault.mint(_depositor, shares);

        emit Deposit(_depositor, shares);
    }


    function _receiveDeposit(
        IERC20 _token,
        address _depositor,
        uint256 _amount,
        uint256 _fee
    ) internal virtual returns (uint256) {
        _token.safeTransferFrom(_depositor, address(this), _amount);

        if (_fee > 0) {
            address feeRecipient = strategy.safeFarmFeeRecipient();
            _token.safeTransfer(feeRecipient, _fee);
            _amount-= _fee;
        }

        return _amount;
    }

    function _swapLPToken(
        address unirouter,
        uint256 _amount,
        address[] memory route,
        uint256 _amountOutMin
    ) internal virtual returns (LPToken memory)
    {
        address tokenB = route[route.length - 1];

        if (route.length > 1) {
            uint256[] memory amounts = IUniswapRouterETH(unirouter).swapExactTokensForTokens(
                _amount,
                _amountOutMin,
                route,
                address(this),
                block.timestamp
            );

            _amount = amounts[amounts.length - 1];
        }

        return LPToken(_amount, tokenB);
    }

    function _addLpLiquidity(
        address _depositor,
        address unirouter,
        LPToken memory lpt0,
        LPToken memory lpt1,
        uint256[] memory _lptOutMin
    ) internal returns (uint256 _liquidity) {
        (
            uint256 amountA,
            uint256 amountB,
            uint256 liquidity
        ) = _addLiquidity(unirouter, lpt0, lpt1, _lptOutMin);

        if (lpt0.amount > amountA) {
            IERC20(lpt0.token).safeTransfer(_depositor, (lpt0.amount - amountA));
        }

        if (lpt1.amount > amountB) {
            IERC20(lpt1.token).safeTransfer(_depositor, (lpt1.amount - amountB));
        }

        return liquidity;
    }

    function _addLiquidity(
        address unirouter,
        LPToken memory lpt0,
        LPToken memory lpt1,
        uint256[] memory _lptOutMin
    ) internal virtual returns (
        uint256 amountA,
        uint256 amountB,
        uint256 liquidity
    ) {
        if (IERC20(lpt0.token).allowance(address(this), unirouter) < lpt0.amount) {
            IERC20(lpt0.token).safeApprove(unirouter, type(uint256).max);
        }

        if (IERC20(lpt1.token).allowance(address(this), unirouter) < lpt1.amount) {
            IERC20(lpt1.token).safeApprove(unirouter, type(uint256).max);
        }

        return IUniswapRouterETH(unirouter).addLiquidity(
            lpt0.token,
            lpt1.token,
            lpt0.amount,
            lpt1.amount,
            _lptOutMin[2],
            _lptOutMin[3],
            address(this),
            block.timestamp
        );
    }


    function _checkRoutesLP(
        address[] memory _route0,
        address[] memory _route1
    ) internal view returns (address tokenA){
        require(_route0[0] == _route1[0], 'different source tokens at routes');

        IUniswapV2Pair LP = IUniswapV2Pair(strategy.want());

        require(LP.token0() == _route0[_route0.length - 1], 'route0 don`t path to lpt0');
        require(LP.token1() == _route1[_route1.length - 1], 'route1 don`t path to lpt1');

        return _route0[0];
    }



    /**
     * @dev Function to send funds into the strategy and put them to work.
     */
    function earn() internal {
        uint256 _bal = available();
        want().safeTransfer(address(strategy), _bal);
        strategy.deposit();

        emit Earn(_bal);
    }

}

interface IVault {
    function totalSupply() external view returns (uint256);
    function balanceOf(address _owner) external view returns (uint256);
    function mint(address _recipient, uint256 _amount) external;
    function burn(address _owner, uint256 _amount) external;
}

interface IStrategy {
    function migrate(address newSafeFarm) external;

    function want() external view returns (address);
    function unirouter() external view returns (address);

    function balanceOf() external view returns (uint256);
    function balanceOfPool() external view returns (uint256);

    function deposit() external;
    function withdraw(address account, uint256 share, uint256 totalShares) external;
    function harvest() external;
    function retireStrat() external;

    function safeSwap(address account,
        uint256 share, uint256 totalShares,
        uint256 fee,
        address[] memory route) external;
    function safeSwap(address account,
        uint256 share, uint256 totalShares,
        uint256 fee,
        address[] memory route0, address[] memory route1) external;

    function safeFarmFeeRecipient() external returns (address);
    function safeFarmFeeAmount(uint256 amount) external returns (uint256);
}

// File: contracts/UniswapInterfaces.sol



//SPDX-License-Identifier: Unlicense
pragma solidity 0.8.7;


interface IUniswapRouterETH {
    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 removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);

    function swapExactTokensForTokens(
        uint amountIn, 
        uint amountOutMin, 
        address[] calldata path, 
        address to, 
        uint deadline
    ) external returns (uint[] memory amounts);

    function getAmountsOut(uint amountIn, address[] calldata path)
        external view
        returns (uint[] memory amounts);
}


interface IUniswapV2Pair {
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);

    function totalSupply() external view returns (uint256);
    function getReserves() external view returns (uint256, uint256);
}
// File: @openzeppelin/contracts/access/AccessControl.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/AccessControl.sol)

pragma solidity ^0.8.0;

import "./IAccessControl.sol";
import "../utils/Context.sol";
import "../utils/Strings.sol";
import "../utils/introspection/ERC165.sol";

/**
 * @dev Contract module that allows children to implement role-based access
 * control mechanisms. This is a lightweight version that doesn't allow enumerating role
 * members except through off-chain means by accessing the contract event logs. Some
 * applications may benefit from on-chain enumerability, for those cases see
 * {AccessControlEnumerable}.
 *
 * Roles are referred to by their `bytes32` identifier. These should be exposed
 * in the external API and be unique. The best way to achieve this is by
 * using `public constant` hash digests:
 *
 * ```
 * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
 * ```
 *
 * Roles can be used to represent a set of permissions. To restrict access to a
 * function call, use {hasRole}:
 *
 * ```
 * function foo() public {
 *     require(hasRole(MY_ROLE, msg.sender));
 *     ...
 * }
 * ```
 *
 * Roles can be granted and revoked dynamically via the {grantRole} and
 * {revokeRole} functions. Each role has an associated admin role, and only
 * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
 *
 * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
 * that only accounts with this role will be able to grant or revoke other
 * roles. More complex role relationships can be created by using
 * {_setRoleAdmin}.
 *
 * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
 * grant and revoke this role. Extra precautions should be taken to secure
 * accounts that have been granted it.
 */
abstract contract AccessControl is Context, IAccessControl, ERC165 {
    struct RoleData {
        mapping(address => bool) members;
        bytes32 adminRole;
    }

    mapping(bytes32 => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /**
     * @dev Modifier that checks that an account has a specific role. Reverts
     * with a standardized message including the required role.
     *
     * The format of the revert reason is given by the following regular expression:
     *
     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
     *
     * _Available since v4.1._
     */
    modifier onlyRole(bytes32 role) {
        _checkRole(role);
        _;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
        return _roles[role].members[account];
    }

    /**
     * @dev Revert with a standard message if `_msgSender()` is missing `role`.
     * Overriding this function changes the behavior of the {onlyRole} modifier.
     *
     * Format of the revert message is described in {_checkRole}.
     *
     * _Available since v4.6._
     */
    function _checkRole(bytes32 role) internal view virtual {
        _checkRole(role, _msgSender());
    }

    /**
     * @dev Revert with a standard message if `account` is missing `role`.
     *
     * The format of the revert reason is given by the following regular expression:
     *
     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
     */
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!hasRole(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "AccessControl: account ",
                        Strings.toHexString(uint160(account), 20),
                        " is missing role ",
                        Strings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
        return _roles[role].adminRole;
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     *
     * May emit a {RoleGranted} event.
     */
    function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
        _grantRole(role, account);
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     *
     * May emit a {RoleRevoked} event.
     */
    function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
        _revokeRole(role, account);
    }

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been revoked `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     *
     * May emit a {RoleRevoked} event.
     */
    function renounceRole(bytes32 role, address account) public virtual override {
        require(account == _msgSender(), "AccessControl: can only renounce roles for self");

        _revokeRole(role, account);
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event. Note that unlike {grantRole}, this function doesn't perform any
     * checks on the calling account.
     *
     * May emit a {RoleGranted} event.
     *
     * [WARNING]
     * ====
     * This function should only be called from the constructor when setting
     * up the initial roles for the system.
     *
     * Using this function in any other way is effectively circumventing the admin
     * system imposed by {AccessControl}.
     * ====
     *
     * NOTE: This function is deprecated in favor of {_grantRole}.
     */
    function _setupRole(bytes32 role, address account) internal virtual {
        _grantRole(role, account);
    }

    /**
     * @dev Sets `adminRole` as ``role``'s admin role.
     *
     * Emits a {RoleAdminChanged} event.
     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = getRoleAdmin(role);
        _roles[role].adminRole = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * Internal function without access restriction.
     *
     * May emit a {RoleGranted} event.
     */
    function _grantRole(bytes32 role, address account) internal virtual {
        if (!hasRole(role, account)) {
            _roles[role].members[account] = true;
            emit RoleGranted(role, account, _msgSender());
        }
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * Internal function without access restriction.
     *
     * May emit a {RoleRevoked} event.
     */
    function _revokeRole(bytes32 role, address account) internal virtual {
        if (hasRole(role, account)) {
            _roles[role].members[account] = false;
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



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

pragma solidity ^0.8.0;

/**
 * @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].
 */
abstract 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() {
        _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 making 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;
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

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

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

// File: @openzeppelin/contracts/access/IAccessControl.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)

pragma solidity ^0.8.0;

/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IAccessControl {
    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {AccessControl-_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) external;
}

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



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

pragma solidity ^0.8.0;

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

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)

pragma solidity ^0.8.0;

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

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

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

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

// File: @openzeppelin/contracts/utils/introspection/ERC165.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

pragma solidity ^0.8.0;

import "./IERC165.sol";

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
 * for the additional interface id that will be supported. For example:
 *
 * ```solidity
 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
 * }
 * ```
 *
 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
 */
abstract contract ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

// File: @openzeppelin/contracts/utils/introspection/IERC165.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)

pragma solidity ^0.8.1;

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

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://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");

        (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");

        (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");

        (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");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

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



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

pragma solidity ^0.8.0;

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

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

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