// Goberian
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// Sources flattened with hardhat v2.7.0 https://hardhat.org

// File @openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol@v4.6.0

// 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);
}

// File @openzeppelin/contracts/token/ERC20/IERC20.sol@v4.6.0

// 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/extensions/IERC20Metadata.sol@v4.6.0

// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

// File @openzeppelin/contracts/utils/Context.sol@v4.6.0

// 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/token/ERC20/ERC20.sol@v4.6.0

// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

/**
 * @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 Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `sender` to `recipient`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

// File erc20-extensions/contracts/lib/SafeMath.sol@v1.1.0

pragma solidity ^0.8.0;

library SafeMathInt {
    function toUint256Safe(int256 a) internal pure returns (uint256) {
        assert(a >= 0);
        return uint256(a);
    }
}

library SafeMathUint {
    function toInt256Safe(uint256 a) internal pure returns (int256) {
        int256 b = int256(a);
        assert(b >= 0);
        return b;
    }
}

// File erc20-extensions/interfaces/IStaking.sol@v1.1.0

pragma solidity ^0.8.0;

/// @title Staking contract for ERC20 tokens
/// @author Daniel Gretzke
/// @notice Allows users to stake an underlying ERC20 token and receive a new ERC20 token in return which tracks their stake in the pool
/// @notice Rewards in form of the underlying ERC20 token are distributed proportionally across all staking participants
/// @notice Rewards in ETH are distributed proportionally across all staking participants
interface IStaking {
    event RewardsReceived(address indexed from, uint256 amount);
    event Deposit(address indexed user, uint256 underlyingToken, uint256 overlyingToken);
    event Withdraw(address indexed user, uint256 underlyingToken, uint256 overlyingToken);
    event RewardClaimed(address indexed user, address indexed to, uint256 amount);

    function claimedRewards(address account) external view returns (uint256 claimedRewards);

    /// @notice allows to deposit the underlying token into the staking contract
    /// @dev mints an amount of overlying tokens according to the stake in the pool
    /// @param amount amount of underlying token to deposit
    /// @return amount of overlying tokens received
    function deposit(uint256 amount) external returns (uint256);

    /// @notice allows to withdraw the underlying token from the staking contract
    /// @param amount of overlying tokens to withdraw
    /// @param claim whether or not to claim ETH rewards
    /// @return amount of underlying tokens withdrawn
    function withdraw(uint256 amount, bool claim) external returns (uint256);

    /// @notice allows to claim accumulated ETH rewards
    /// @param to address to send rewards to
    /// @return amount of rewards claimed
    function claimRewards(address to) external returns (uint256);

    /// @return accumulated underlying token balance that can be withdrawn by the user
    function tokenBalance(address user) external view returns (uint256);

    /// @return total amount of ETH rewards earned by user
    function totalRewardsEarned(address user) external view returns (uint256);

    /// @return amount of ETH rewards that can be claimed by user
    function claimableRewardsOf(address user) external view returns (uint256);
}

// File erc20-extensions/contracts/staking/Staking.sol@v1.1.0

pragma solidity ^0.8.0;

contract Staking is ERC20, IStaking {
    using SafeMathUint for uint256;
    using SafeMathInt for int256;

    uint256 private constant MAX_UINT256 = type(uint256).max;
    // allows to distribute small amounts of ETH correctly
    uint256 private constant MAGNITUDE = 10**40;

    IERC20 token;
    uint256 private _magnifiedRewardPerShare;
    mapping(address => int256) private _magnifiedRewardCorrections;
    mapping(address => uint256) public claimedRewards;

    constructor(
        string memory name,
        string memory symbol,
        address underlyingToken
    ) ERC20(name, symbol) {
        token = IERC20(underlyingToken);
    }

    /// @notice when the smart contract receives ETH, register payment
    /// @dev can only receive ETH when tokens are staked
    receive() external payable virtual {
        require(totalSupply() > 0, "NO_TOKENS_STAKED");
        if (msg.value > 0) {
            _magnifiedRewardPerShare += (msg.value * MAGNITUDE) / totalSupply();
            emit RewardsReceived(_msgSender(), msg.value);
        }
    }

    function deposit(uint256 amount) public virtual returns (uint256) {
        uint256 share = 0;
        if (totalSupply() > 0) {
            share = (totalSupply() * amount) / token.balanceOf(address(this));
        } else {
            share = amount;
        }
        token.transferFrom(_msgSender(), address(this), amount);
        _mint(_msgSender(), share);
        emit Deposit(_msgSender(), amount, share);
        return share;
    }

    function withdraw(uint256 amount, bool claim) external virtual returns (uint256) {
        if (claim) {
            claimRewards(_msgSender());
        }
        uint256 withdrawnTokens = (amount * token.balanceOf(address(this))) / totalSupply();
        _burn(_msgSender(), amount);
        token.transfer(_msgSender(), withdrawnTokens);
        emit Withdraw(_msgSender(), withdrawnTokens, amount);
        return withdrawnTokens;
    }

    function claimRewards(address to) public virtual returns (uint256) {
        uint256 claimableRewards = claimableRewardsOf(_msgSender());
        if (claimableRewards > 0) {
            claimedRewards[_msgSender()] += claimableRewards;
            (bool success, ) = to.call{value: claimableRewards}("");
            require(success, "ETH_TRANSFER_FAILED");
            emit RewardClaimed(_msgSender(), to, claimableRewards);
        }
        return claimableRewards;
    }

    /// @dev on mint, burn and transfer adjust corrections so that ETH rewards don't change on these events
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual override {
        super._beforeTokenTransfer(from, to, amount);

        if (from == address(0)) {
            // mint
            _magnifiedRewardCorrections[to] -= (_magnifiedRewardPerShare * amount).toInt256Safe();
        } else if (to == address(0)) {
            // burn
            _magnifiedRewardCorrections[from] += (_magnifiedRewardPerShare * amount).toInt256Safe();
        } else {
            // transfer
            require(_isTransferable(), "TRANSFER_FORBIDDEN");
            int256 magnifiedCorrection = (_magnifiedRewardPerShare * amount).toInt256Safe();
            _magnifiedRewardCorrections[from] += (magnifiedCorrection);
            _magnifiedRewardCorrections[to] -= (magnifiedCorrection);
        }
    }

    function tokenBalance(address user) public view virtual returns (uint256) {
        if (totalSupply() == 0) {
            return 0;
        }
        return (balanceOf(user) * token.balanceOf(address(this))) / totalSupply();
    }

    function totalRewardsEarned(address user) public view virtual returns (uint256) {
        int256 magnifiedRewards = (_magnifiedRewardPerShare * balanceOf(user)).toInt256Safe();
        uint256 correctedRewards = (magnifiedRewards + _magnifiedRewardCorrections[user]).toUint256Safe();
        return correctedRewards / MAGNITUDE;
    }

    function claimableRewardsOf(address user) public view virtual returns (uint256) {
        return totalRewardsEarned(user) - claimedRewards[user];
    }

    function _isTransferable() internal view virtual returns (bool) {
        return false;
    }
}

// File erc20-extensions/interfaces/IStakingPermit.sol@v1.1.0

pragma solidity ^0.8.0;

/// @notice see Staking.sol
/// @dev adds support for depositing tokens with permit if underlying token supports EIP2612
interface IStakingPermit {
    /// @notice allows to deposit tokens without an approve transaction by using the EIP2612 permit standard
    /// @param amount amount of underlying token to deposit
    /// @param deadline until the signature is valid
    /// @param signature permit signature
    /// @return amount of overlying tokens received
    function depositWithPermit(
        uint256 amount,
        uint256 deadline,
        bytes memory signature
    ) external returns (uint256);
}

// File erc20-extensions/contracts/staking/StakingPermit.sol@v1.1.0

pragma solidity ^0.8.0;

contract StakingPermit is IStakingPermit, Staking {
    constructor(
        string memory name,
        string memory symbol,
        address underlyingToken
    ) Staking(name, symbol, underlyingToken) {}

    function depositWithPermit(
        uint256 amount,
        uint256 deadline,
        bytes memory signature
    ) external virtual returns (uint256) {
        require(signature.length == 65);
        bytes32 r;
        bytes32 s;
        uint8 v;

        assembly {
            r := mload(add(signature, 32))
            s := mload(add(signature, 64))
            v := byte(0, mload(add(signature, 96)))
        }

        IERC20Permit(address(token)).permit(_msgSender(), address(this), type(uint256).max, deadline, v, r, s);
        return deposit(amount);
    }
}

// File contracts/GoberianStaking.sol

pragma solidity 0.8.14;

contract GoberianStaking is StakingPermit {
    constructor(address _underlyingToken) StakingPermit("Staked Goberian", "stGOBE", _underlyingToken) {}

    function _isTransferable() internal view virtual override returns (bool) {
        return true;
    }
}