// 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/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/access/Ownable.sol



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

pragma solidity ^0.8.0;

import "../utils/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.
 */
abstract 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() {
        _transferOwnership(_msgSender());
    }

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

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        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 {
        _transferOwnership(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");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

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



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

pragma solidity ^0.8.0;

import "../utils/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.
 */
abstract 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() {
        _paused = false;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Throws if the contract is paused.
     */
    function _requireNotPaused() internal view virtual {
        require(!paused(), "Pausable: paused");
    }

    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        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());
    }
}

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



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

pragma solidity ^0.8.0;

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

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.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 `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _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: @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);
}

// File: @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol



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

pragma solidity ^0.8.0;

import "../IERC20.sol";

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

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

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

// 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/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/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/Counters.sol



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

pragma solidity ^0.8.0;

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

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

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

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

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

// File: @openzeppelin/contracts/utils/cryptography/draft-EIP712.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol)

pragma solidity ^0.8.0;

import "./ECDSA.sol";

/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
    uint256 private immutable _CACHED_CHAIN_ID;
    address private immutable _CACHED_THIS;

    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;

    /* solhint-enable var-name-mixedcase */

    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        bytes32 hashedName = keccak256(bytes(name));
        bytes32 hashedVersion = keccak256(bytes(version));
        bytes32 typeHash = keccak256(
            "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
        );
        _HASHED_NAME = hashedName;
        _HASHED_VERSION = hashedVersion;
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
        _CACHED_THIS = address(this);
        _TYPE_HASH = typeHash;
    }

    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
        }
    }

    function _buildDomainSeparator(
        bytes32 typeHash,
        bytes32 nameHash,
        bytes32 versionHash
    ) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
    }

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.3) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;

import "../Strings.sol";

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

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

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

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

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

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

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

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

        return (signer, RecoverError.NoError);
    }

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

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

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

    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
    }
}

// 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/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: contracts/blocklist/extensions/UserBlocklist.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

import { IGetStatus } from "../interfaces/IGetStatus.sol";
import { IGetUserStatus } from "../interfaces/IGetUserStatus.sol";
import { VerboseReverts } from "../libraries/VerboseReverts.sol";

import { ERC165 } from "@openzeppelin/contracts/utils/introspection/ERC165.sol";

bytes4 constant USER_LOCK_HASH = 0x91659165;

// Check if user is blocked and perform action
contract UserBlocklist is ERC165 {
    struct BlocklistInfo {
        bool enabled;
        address blocklist;
    }

    event BlocklistChanged(address indexed oldBlocklist, address indexed newBlocklist);
    event BlocklistStatusChanged(bool indexed newStatus);

    string internal constant USERLOCK_MESSAGE = "UserBlocklist: Action is blocked for";

    // For some gas optimization these two variables are in the same slot, so they can be read in one SLOAD
    BlocklistInfo private _blocklistInfo;

    /**
     * @param blocklist_ address of the blocklist
     */
    constructor(address blocklist_) {
        _setBlocklist(blocklist_);
    }

    /**
     * @inheritdoc ERC165
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165) returns (bool) {
        return interfaceId == USER_LOCK_HASH || super.supportsInterface(interfaceId);
    }

    /**
     * @dev Returns the address of the blocklist.
     * @return address of the blocklist
     */
    function blocklist() public view returns (address) {
        return _blocklistInfo.blocklist;
    }

    /**
     * @dev If true the blocklist is enabled, false otherwise.
     * @param state true if the blocklist is enabled, false otherwise
     */
    function _changeBlocklistState(bool state) internal virtual {
        emit BlocklistStatusChanged(state);
        _blocklistInfo.enabled = state;
    }

    /**
     * @dev Sets the address of the blocklist.
     * @param blocklist_ address of the blocklist
     */
    function _setBlocklist(address blocklist_) internal virtual {
        emit BlocklistChanged(_blocklistInfo.blocklist, blocklist_);
        _blocklistInfo.blocklist = blocklist_;

        _changeBlocklistState(blocklist_ == address(0) ? false : true);
    }

    /**
     * @dev Returns blocklist info.
     * @return Full blocklist info
     */
    function _getBlocklist() internal view returns (BlocklistInfo memory) {
        return _blocklistInfo;
    }

    /**
     * @dev Reverts if the user is blocked.
     * @param user address of the user
     * @param message message to revert with
     */
    function _checkIfActionIsAllowed(address user, string memory message) internal view virtual {
        BlocklistInfo memory ri = _blocklistInfo;
        if (!ri.enabled) return;
        _checkIfActionIsAllowed(ri.blocklist, user, message);
    }

    /**
     * @dev Reverts if the user is blocked.
     * @param blocklist_ address of the blocklist
     * @param user address of the user
     * @param message message to revert with
     */
    function _checkIfActionIsAllowed(address blocklist_, address user, string memory message) internal view virtual {
        if (IGetUserStatus(blocklist_).isUserBlocked(user)) {
            VerboseReverts._revertWithAddress(bytes(message).length > 0 ? message : USERLOCK_MESSAGE, user);
        }
    }

    /**
     * @dev Reverts if any of the users are blocked.
     * @param users array of addresses of the users
     * @param message message to revert with
     */
    function _batchCheckIfActionIsAllowed(address[] memory users, string memory message) internal view virtual {
        BlocklistInfo memory ri = _blocklistInfo;
        if (!ri.enabled) return;
        _batchCheckIfActionIsAllowed(ri.blocklist, users, message);
    }

    /**
     * @dev Reverts if any of the users are blocked.
     * @param blocklist_ address of the blocklist
     * @param users array of addresses of the users
     * @param message message to revert with
     */
    function _batchCheckIfActionIsAllowed(
        address blocklist_,
        address[] memory users,
        string memory message
    ) internal view virtual {
        bool[] memory statuses = IGetUserStatus(blocklist_).batchIsUserBlocked(users);
        for (uint256 i = 0; i < users.length; i++) {
            if (statuses[i]) {
                VerboseReverts._revertWithAddress(bytes(message).length > 0 ? message : USERLOCK_MESSAGE, users[i]);
            }
        }
    }
}

// File: contracts/blocklist/interfaces/IGetStatus.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

interface IGetStatus {
    /**
     * @dev Returns if the user is blocked and if the token is blocked
     * @param user The user address
     * @param contractAddress The contract address
     * @param tokenId The token id
     * @return (userBlocked, tokenBlocked)
     */
    function userTokenIdBlockStatus(
        address user,
        address contractAddress,
        uint256 tokenId
    ) external view returns (bool, bool);

    /**
     * @dev Returns if the user is blocked and if the tokens are blocked
     * @param user The user address
     * @param contractAddress The contract address
     * @param tokenIds Array of token ids
     * @return (userBlocked, tokenIdsBlocked)
     */
    function userTokenIdsBlockStatus(
        address user,
        address contractAddress,
        uint256[] calldata tokenIds
    ) external view returns (bool, bool[] memory);

    /**
     * @dev Returns if the user is blocked and if the tokens are blocked
     * @param users Array of user addresses
     * @param contractAddress The contract address
     * @param tokenId The token id
     * @return (usersBlocked, tokenBlocked)
     */
    function usersTokenIdBlockStatus(
        address[] calldata users,
        address contractAddress,
        uint256 tokenId
    ) external view returns (bool[] memory, bool);

    /**
     * @dev Returns if the users are blocked and if the tokens ids of a token are blocked
     * @param users Array of user addresses
     * @param contractAddress The contract address
     * @param tokenIds Array of token ids
     * @return (usersBlocked, tokenIdsBlocked)
     */
    function usersTokenIdsBlockStatus(
        address[] calldata users,
        address contractAddress,
        uint256[] calldata tokenIds
    ) external view returns (bool[] memory, bool[] memory);

    /**
     * @dev Returns if the users are blocked and if the tokens are blocked
     * @param users Array of user addresses
     * @param contractAddresses Array of contract addresses
     * @param tokenIds Array of token ids
     * @return (usersBlocked, tokenIdsBlocked)
     */
    function usersTokensIdsBlockStatus(
        address[] calldata users,
        address[] calldata contractAddresses,
        uint256[][] calldata tokenIds
    ) external view returns (bool[] memory, bool[][] memory);
}

// File: contracts/blocklist/interfaces/IGetUserStatus.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

interface IGetUserStatus {
    /**
     * @dev Returns true if the user is blocked.
     * @param user address of the user
     * @return true if the user is blocked, false otherwise
     */
    function isUserBlocked(address user) external view returns (bool);

    /**
     * @dev Returns true if the user is blocked.
     * @param users array of addresses of the users
     * @return array of booleans, true if the user is blocked, false otherwise
     */
    function batchIsUserBlocked(address[] calldata users) external view returns (bool[] memory);
}

// File: contracts/blocklist/libraries/VerboseReverts.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";

library VerboseReverts {
    function _revertWithAddress(string memory message, address user) internal pure {
        revert(string(abi.encodePacked(message, ": ", Strings.toHexString(uint160(user), 20))));
    }

    function _revertWithUint(string memory message, uint256 value) internal pure {
        revert(string(abi.encodePacked(message, ": ", Strings.toHexString(value, 32))));
    }
}

// File: contracts/kale-bridge-v2/BridgeBase.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/security/Pausable.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

import "./BridgeUserBlocklist.sol";
import "./BridgeTransfer.sol";
import "./BridgeSignatureTransfer.sol";
import "./BridgeSignatures.sol";
import "./BridgeRefundRequest.sol";
import "./BridgeRoles.sol";

contract BridgeBase is Pausable, BridgeSignatures, BridgeSignatureTransfer, BridgeUserBlocklist, BridgeRefundRequest {
    event EmergencyTokenWithdraw(address indexed token, address indexed to, uint amount, uint timestamp);

    using SafeERC20 for IERC20;

    constructor(
        address owner_,
        address admin_,
        address refundManager_,
        address[] memory signers_,
        address token_,
        address blocklist_,
        string memory name
    )
        BridgeUserBlocklist(blocklist_)
        BridgeRoles(owner_, admin_, refundManager_, signers_)
        BridgeSignatures(name, "1")
        BridgeTransfer(token_)
    {
        _setMinTeleportAmount(1000);
    }

    receive() external payable {
        revert("Bridge: ether can not be sent to the bridge contract");
    }

    modifier moreThanMinTeleportAmount(uint amount) {
        require(amount >= minTeleportAmount, "Bridge: amount is less than min teleport amount");
        _;
    }

    /**
     * @inheritdoc IERC165
     */
    function supportsInterface(
        bytes4 interfaceId
    ) public view virtual override(BridgeUserBlocklist, AccessControl) returns (bool) {
        return AccessControl.supportsInterface(interfaceId) || BridgeUserBlocklist.supportsInterface(interfaceId);
    }

    /******************************************************************************/
    /*                     BridgeTransfer & BridgeSigTransfer                     */
    /******************************************************************************/

    /**
     * @dev Teleports tokens from the user to the bridge contract.
     * @param amount The amount of tokens to teleport.
     * @notice The user must approve the bridge contract to transfer the tokens.
     */
    function teleport(
        uint256 amount
    ) external userIsNotBlocked(msg.sender) whenNotPaused moreThanMinTeleportAmount(amount) {
        _teleport(msg.sender, address(this), amount);
    }

    /**
     * @dev Teleports tokens from the user to the bridge contract.
     * @param from The address of the user to teleport the tokens from.
     * @param amount The amount of tokens to teleport.
     * @param deadline The deadline for the signature.
     * @param r The signature's R value.
     * @param s The signature's S value.
     * @param v The signature's V value.
     * @notice The user must approve the bridge contract to transfer the tokens.
     */
    function teleportSig(
        address from,
        uint256 amount,
        uint256 deadline,
        bytes32 r,
        bytes32 s,
        uint8 v
    ) external userIsNotBlocked(from) whenNotPaused moreThanMinTeleportAmount(amount) {
        _teleportSig(from, amount, deadline, r, s, v);
    }

    /**
     * @dev Claims tokens from the bridge contract to the user.
     * @param to The address of the user to claim the tokens to.
     * @param amount The amount of tokens to claim.
     * @param otherChainNonce The nonce of the teleport on the other chain.
     * @param signerInfo The array of signer info.
     */
    function claimSig(
        address to,
        uint256 amount,
        uint256 otherChainNonce,
        SignatureWithDeadline[] calldata signerInfo
    ) external userIsNotBlocked(to) whenNotPaused {
        _claimSig(to, amount, otherChainNonce, signerInfo);
    }

    /**
     * @dev Sets the minimum amount of tokens to teleport.
     * @param amount The minimum amount of tokens to teleport.
     */
    function setMinTeleportAmount(uint256 amount) external onlyOwner whenNotPaused {
        _setMinTeleportAmount(amount);
    }

    /******************************************************************************/
    /*                            BridgeRefundRequest                             */
    /******************************************************************************/

    // To open refund request user must call openRefundRequest function first
    // After it's done user must await for the refund request to be approved or declined
    // In case of approval tokens will be transferred to the user instantly
    // In case of decline tokens will not be transferred, but user can contact us to reopen the refund request
    // Either approve or decline of refund request cannot be done quicker than 1 day after the request was opened due to security reasons

    /**
     * @notice Approves a refund request.
     * @param nonce The nonce of the refund(teleport) request.
     * @param signatures The signatures for the refund.
     */
    function approveRefund(
        uint256 nonce,
        SignatureWithDeadline[] memory signatures
    ) external onlyRefundManager whenNotPaused {
        _approveRefund(nonce, signatures);
    }

    /**
     * @notice Declines a refund request.
     * @param nonce The nonce of the refund(teleport) request.
     */
    function declineRefund(uint256 nonce) external onlyRefundManager whenNotPaused {
        _declineRefund(nonce);
    }

    /**
     * @notice Reopens a refund request.
     * @param nonce The nonce of the refund(teleport) request.
     */
    function reopenRefund(uint256 nonce) external onlyRefundManager whenNotPaused {
        _reopenRefund(nonce);
    }

    /**
     * @notice Opens a refund request.
     * @param nonces The nonces of the refund(teleport) requests.
     * @param approved The status of the refund requests.
     * @param signatures Signatures for each of the approved refunds.
     */
    function processRefunds(
        uint256[] calldata nonces,
        bool[] calldata approved,
        SignatureWithDeadline[][] memory signatures
    ) external onlyRefundManager whenNotPaused {
        require(nonces.length == approved.length, "Bridge: nonces and approved arrays must have the same length");
        require(nonces.length == signatures.length, "Bridge: nonces and signatures arrays must have the same length");
        for (uint256 i = 0; i < nonces.length; i++) {
            if (approved[i]) {
                _approveRefund(nonces[i], signatures[i]);
            } else {
                _declineRefund(nonces[i]);
            }
        }
    }

    /******************************************************************************/
    /*                                                                            */
    /******************************************************************************/

    /**
     * @dev Returns the status of the nonces.
     * @param nonces The nonces to check.
     */
    function areProcessedNonces(uint256[] calldata nonces) external view returns (bool[] memory) {
        uint256 length = nonces.length;
        bool[] memory result = new bool[](length);
        for (uint256 i = 0; i < length; i++) {
            result[i] = processedNonces[nonces[i]];
        }
        return result;
    }

    /******************************************************************************/
    /*                                  Pausable                                  */
    /******************************************************************************/

    /**
     * @dev Pauses the bridge.
     */
    function pause() external onlyAdmin {
        _pause();
    }

    /**
     * @dev Unpauses the bridge.
     */
    function unpause() external onlyAdmin {
        _unpause();
    }

    /******************************************************************************/
    /*                                    Misc                                    */
    /******************************************************************************/

    /**
     * @dev This function can be used if the bridge contract receives tokens by mistake or some scam tokens are transferred to contract.
     * @param tokens The tokens to withdraw.
     */
    function withdrawTokens(address[] memory tokens) external onlyOwner {
        address bridgeToken = address(token);
        for (uint256 i = 0; i < tokens.length; i++) {
            require(
                tokens[i] != bridgeToken,
                "Bridge: token address is the same as the bridge token. Can not withdraw bridge token."
            );
            uint256 amount = IERC20(tokens[i]).balanceOf(address(this));
            IERC20(tokens[i]).safeTransfer(_msgSender(), amount);
        }
    }

    /**
     * @dev This function can be used if the bridge contract receives ether by mistake.
     */
    function withdrawEther() external onlyOwner {
        payable(_msgSender()).transfer(address(this).balance);
    }
}

// File: contracts/kale-bridge-v2/BridgeEth.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;

import "./BridgeBase.sol";

contract BridgeEth is BridgeBase {
    constructor(
        address owner_,
        address admin_,
        address refundManager_,
        address[] memory signers_,
        address token,
        address blocklist_
    ) BridgeBase(owner_, admin_, refundManager_, signers_, token, blocklist_, "ETH_KALE_BRIDGE") {}
}

// File: contracts/kale-bridge-v2/BridgeRefundRequest.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

import "./BridgeTransfer.sol";
import "./BridgeSignatures.sol";

// Import SafeERC20 from OpenZeppelin Contracts
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

abstract contract BridgeRefundRequest is BridgeTransfer, BridgeSignatures {
    using SafeERC20 for IERC20;

    event RefundStatusChanged(
        address indexed from,
        uint256 indexed nonce,
        RefundStatus indexed status,
        uint64 timestamp
    );

    enum RefundStatus {
        None,
        Requested,
        Claimed,
        Declined
    }

    uint256 public constant REFUND_REQUEST_MIN_DELAY = 1 days;
    bytes32 public constant REFUND_APPROVE_SIGNATURE =
        keccak256("REFUND_APPROVE_SIGNATURE(uint256 nonce,bool approved,uint256 deadline)");

    /**
     * @dev Refund request struct.
     * @param status The status of the refund request.
     * @param timestamp The timestamp of the refund request.
     * @param from The address of the user who requested the refund.
     * @param nonce The nonce of the teleport.
     */
    struct RefundRequest {
        RefundStatus status;
        uint64 timestamp;
        address from;
        uint256 nonce;
    }

    mapping(uint256 => RefundRequest) public refundRequests;

    /**
     * @dev Modifier to check if the refund request exists and is in the requested state.
     * @param nonce The nonce of the request(teleport).
     */
    modifier onlyRequestedRefund(uint256 nonce) {
        require(
            refundRequests[nonce].status == RefundStatus.Requested,
            "Bridge: Refund not requested or is already processed"
        );
        _;
    }

    /**
     * @dev Modifier to check if the refund request delay has passed.
     * @param nonce The nonce of the request(teleport).
     */
    modifier onlyRefundRequestDelayPassed(uint256 nonce) {
        require(
            refundRequests[nonce].timestamp + REFUND_REQUEST_MIN_DELAY <= block.timestamp,
            "Bridge: Refund request delay has not passed"
        );
        _;
    }

    /**
     * @dev Requests a refund for a teleport if tokens were not transferred for some reason.
     * @param nonce The nonce of the teleport.
     */
    function requestRefund(uint256 nonce) public {
        require(
            teleports[nonce].from == msg.sender,
            "Bridge: Only the sender can request a refund or teleport does not exist"
        );
        require(
            refundRequests[nonce].status == RefundStatus.None,
            "Bridge: Refund already requested or is already processed"
        );

        emit RefundStatusChanged(msg.sender, nonce, RefundStatus.Requested, uint64(block.timestamp));

        refundRequests[nonce] = RefundRequest({
            status: RefundStatus.Requested,
            timestamp: uint64(block.timestamp),
            from: msg.sender,
            nonce: nonce
        });
    }

    /**
     * @dev Approves a refund request.
     * @param nonce The nonce of the teleport.
     * @param signatures Signatures for the approved refund.
     */
    function _approveRefund(
        uint256 nonce,
        SignatureWithDeadline[] memory signatures
    ) internal onlyRequestedRefund(nonce) onlyRefundRequestDelayPassed(nonce) {
        bytes32[] memory digests = new bytes32[](signatures.length);

        for (uint256 id = 0; id < signatures.length; id++) {
            digests[id] = _getRefundApproveDigest(nonce, signatures[id].deadline);
        }

        _checkSignatures(digests, signatures);

        emit RefundStatusChanged(refundRequests[nonce].from, nonce, RefundStatus.Claimed, uint64(block.timestamp));

        refundRequests[nonce].status = RefundStatus.Claimed;

        token.safeTransfer(refundRequests[nonce].from, teleports[nonce].amount);
    }

    /**
     * @dev Declines a refund request.
     * @param nonce The nonce of the teleport.
     */
    function _declineRefund(uint256 nonce) internal onlyRequestedRefund(nonce) onlyRefundRequestDelayPassed(nonce) {
        emit RefundStatusChanged(refundRequests[nonce].from, nonce, RefundStatus.Declined, uint64(block.timestamp));

        refundRequests[nonce].status = RefundStatus.Declined;
    }

    /**
     * @dev Reopens a declined refund request.
     * @param nonce The nonce of the teleport.
     */
    function _reopenRefund(uint256 nonce) internal {
        require(refundRequests[nonce].status == RefundStatus.Declined, "Bridge: Refund not declined");

        emit RefundStatusChanged(refundRequests[nonce].from, nonce, RefundStatus.Requested, uint64(block.timestamp));

        refundRequests[nonce].status = RefundStatus.Requested;
        refundRequests[nonce].timestamp = uint64(block.timestamp);
    }

    /**
     * @dev Get typehash of the refund request
     * @param nonce Nonce of the refund to process
     * @param deadline Deadline of the signature
     */
    function _getRefundApproveDigest(uint256 nonce, uint256 deadline) internal view returns (bytes32) {
        bytes32 structHash = keccak256(abi.encode(REFUND_APPROVE_SIGNATURE, nonce, true, deadline));
        bytes32 digest = _hashTypedDataV4(structHash);
        return digest;
    }
}

// File: contracts/kale-bridge-v2/BridgeRoles.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

// Import AccessControl from OpenZeppelin Contracts
import "@openzeppelin/contracts/access/AccessControl.sol";

abstract contract BridgeRoles is AccessControl {
    bytes32 public constant SIGNER_ROLE = keccak256("SIGNER_ROLE");
    bytes32 public constant ADMIN_ROLE = keccak256("ADMIN_ROLE");
    bytes32 public constant OWNER_ROLE = keccak256("OWNER_ROLE");
    bytes32 public constant REFUND_ROLE = keccak256("REFUND_ROLE");

    uint256 public signerCount = 0;

    /**
     * @dev Grant the admin role to the deployer and the signer role to the signers.
     * @param owner The address of the owner.
     * @param admin The address of the admin.
     * @param refundManager The address of the refund manager.
     * @param signers The addresses of the signers.
     */
    constructor(address owner, address admin, address refundManager, address[] memory signers) {
        _grantRole(OWNER_ROLE, owner);
        _grantRole(ADMIN_ROLE, admin);
        _grantRole(REFUND_ROLE, refundManager);

        for (uint256 i = 0; i < signers.length; i++) {
            _addSigner(signers[i]);
        }
    }

    modifier onlyOwner() {
        require(hasRole(OWNER_ROLE, msg.sender), "BridgeRoles: Caller is not the owner");
        _;
    }

    modifier onlyAdmin() {
        require(hasRole(ADMIN_ROLE, msg.sender), "BridgeRoles: Caller is not an admin");
        _;
    }

    modifier onlyRefundManager() {
        require(hasRole(REFUND_ROLE, msg.sender), "BridgeRoles: Caller is not a refund manager");
        _;
    }

    /**
     * @dev Add owner.
     * @param account The address of the owner.
     */
    function addOwner(address account) external onlyOwner {
        _grantRole(OWNER_ROLE, account);
    }

    /**
     * @dev Revoke owner.
     * @param account The address of the owner.
     */
    function revokeOwner(address account) external onlyOwner {
        require(account != msg.sender, "BridgeRoles: Cannot revoke self from owner");
        _revokeRole(OWNER_ROLE, account);
    }

    /**
     * @dev Add admin.
     * @param account The address of the admin.
     */
    function addAdmin(address account) external onlyOwner {
        _grantRole(ADMIN_ROLE, account);
    }

    /**
     * @dev Revoke admin.
     * @param account The address of the admin.
     */
    function revokeAdmin(address account) external onlyOwner {
        _revokeRole(ADMIN_ROLE, account);
    }

    /**
     * @dev Add refund manager.
     * @param account The address of the refund manager.
     */
    function addRefundManager(address account) external onlyOwner {
        _grantRole(REFUND_ROLE, account);
    }

    /**
     * @dev Revoke refund manager.
     * @param account The address of the refund manager.
     */
    function revokeRefundManager(address account) external onlyOwner {
        _revokeRole(REFUND_ROLE, account);
    }

    /**
     * @dev Add signers.
     * @param accounts The addresses of the signers.
     */
    function addSigners(address[] calldata accounts) external onlyOwner {
        for (uint256 i = 0; i < accounts.length; i++) {
            _addSigner(accounts[i]);
        }
    }

    /**
     * @dev Revoke signers.
     * @param accounts The addresses of the signers.
     */
    function revokeSigners(address[] calldata accounts) external onlyOwner {
        for (uint256 i = 0; i < accounts.length; i++) {
            _revokeSigner(accounts[i]);
        }
    }

    /**
     * @dev This function is overridden to prevent renouncing roles.
     * @inheritdoc AccessControl
     */
    function renounceRole(bytes32, address) public pure override {
        revert("BridgeRoles: Cannot renounce roles");
    }

    /**
     * @dev This function is overridden to prevent granting roles.
     * @inheritdoc AccessControl
     */
    function grantRole(bytes32, address) public pure override {
        revert("BridgeRoles: Cannot grant roles");
    }

    /**
     * @dev This function is overridden to prevent revoking roles.
     * @inheritdoc AccessControl
     */
    function revokeRole(bytes32, address) public pure override {
        revert("BridgeRoles: Cannot revoke roles");
    }

    /**
     * @dev Add signer and increment signer count.
     * @param account The address of the signer.
     */
    function _addSigner(address account) private {
        if (!hasSignerRole(account)) {
            _grantRole(SIGNER_ROLE, account);
            signerCount++;
        }
    }

    /**
     * @dev Revoke signer and decrement signer count.
     * @param account The address of the signer.
     */
    function _revokeSigner(address account) private {
        if (hasSignerRole(account)) {
            _revokeRole(SIGNER_ROLE, account);
            signerCount--;
        }
    }

    function hasSignerRole(address account) public view returns (bool) {
        return hasRole(SIGNER_ROLE, account);
    }
}

// File: contracts/kale-bridge-v2/BridgeSignatures.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

import { ECDSA } from "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
import { EIP712 } from "@openzeppelin/contracts/utils/cryptography/draft-EIP712.sol";

import "./BridgeRoles.sol";

abstract contract BridgeSignatures is EIP712, BridgeRoles {
    struct SignatureWithDeadline {
        uint256 deadline;
        bytes32 r;
        bytes32 s;
        uint8 v;
    }

    enum SigInvalidReason {
        None,
        Deadline,
        Recover,
        Signer
    }

    event InvalidSigDetected(uint256 id, SigInvalidReason reason);

    constructor(string memory name, string memory version) EIP712(name, version) {}

    /**
     * @dev Check sigantures for the bridge contract.
     * @param sigs The signatures of the backend signers.
     */
    function _checkSignatures(bytes32[] memory structHashes, SignatureWithDeadline[] memory sigs) internal {
        uint256 _requiredSignatures = requiredSignatures();

        // Check if the amount of signatures is enough (>= requiredSignatures)
        require(sigs.length >= _requiredSignatures, "Bridge: Not enough signatures");
        require(sigs.length <= signerCount, "Bridge: Too many signatures");

        // Instead of checking the signatures one by one, we check the amount of incorrect signatures.
        // In this way, we can save some gas if the signatures are incorrect.

        uint256 possibleIncorrectSignatures = sigs.length - _requiredSignatures;
        uint256 incorrectSignatures = 0;
        uint256 correctSignatures = 0;

        // This variable is used to check for unique signatures.
        // Check https://github.com/balancer-labs/balancer-v2-monorepo/blob/537076996a93d654b19e2074f1bd952b70fbfcd0/pkg/vault/contracts/FlashLoans.sol#L50 for more info.
        address _uniqueSigner = address(0);

        for (uint256 i = 0; i < sigs.length; i++) {
            SignatureWithDeadline memory info = sigs[i];

            // Check if the deadline has passed, if the signature is valid and if the signer has the claim signer role.

            bool validDeadline = _checkDeadline(info.deadline);

            if (!validDeadline) {
                incorrectSignatures++;
                emit InvalidSigDetected(i, SigInvalidReason.Deadline);
                _requireCorrectSigsAmount(incorrectSignatures, possibleIncorrectSignatures);
                continue;
            }

            address signer = _getSignerAddress(structHashes[i], sigs[i]);

            if (signer == address(0)) {
                incorrectSignatures++;
                emit InvalidSigDetected(i, SigInvalidReason.Recover);
                _requireCorrectSigsAmount(incorrectSignatures, possibleIncorrectSignatures);
                continue;
            }

            bool signerIsCorrect = hasSignerRole(signer);

            if (!signerIsCorrect) {
                incorrectSignatures++;
                emit InvalidSigDetected(i, SigInvalidReason.Signer);
                _requireCorrectSigsAmount(incorrectSignatures, possibleIncorrectSignatures);
                continue;
            }

            // Used to check for unique signatures.
            require(signer > _uniqueSigner, "Bridge: Signatures must be unique");

            _uniqueSigner = signer;
            correctSignatures++;
            if (correctSignatures == _requiredSignatures) {
                break;
            }
        }
    }

    function _requireCorrectSigsAmount(uint256 incorrectSignatures, uint256 possibleIncorrectSignatures) internal pure {
        require(incorrectSignatures <= possibleIncorrectSignatures, "Bridge: Too many incorrect signatures");
    }

    /**
     * @dev Checks if the deadline has passed.
     * @param deadline The deadline to check.
     */
    function _checkDeadline(uint256 deadline) internal view returns (bool) {
        return deadline >= block.timestamp;
    }

    /**
     * @dev Get signer address using ECDSA
     * @param digest Typed data hash
     * @param sig Signature provided for the hash
     */
    function _getSignerAddress(bytes32 digest, SignatureWithDeadline memory sig) internal pure returns (address) {
        (address signer, ) = ECDSA.tryRecover(digest, sig.v, sig.r, sig.s);

        return signer;
    }

    /**
     * @dev Required amount of signers is calculated as follows:
     *  0 -> Reverts
        1 -> 1
        2 -> 2
        3 -> 3
        4 -> 3
        5 -> 4
        6 -> 5
        7 -> 5
        ...
        14 -> 10
        15 -> 11
        ...
     */
    function requiredSignatures() public view returns (uint256) {
        uint256 totalSigners = signerCount;

        return (totalSigners * 2) / 3 + 1;
    }
}

// File: contracts/kale-bridge-v2/BridgeSignatureTransfer.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

import { ECDSA } from "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
import { EIP712 } from "@openzeppelin/contracts/utils/cryptography/draft-EIP712.sol";

import "./BridgeTransfer.sol";
import "./BridgeRoles.sol";
import "./BridgeSignatures.sol";

abstract contract BridgeSignatureTransfer is BridgeTransfer, BridgeSignatures {
    bytes32 public constant TELEPORT_TYPEHASH =
        keccak256("Teleport(address from,uint256 amount,uint256 nonce,uint256 deadline)");

    bytes32 public constant CLAIM_TYPEHASH =
        keccak256("Claim(address to,uint256 amount,uint256 otherChainNonce,uint256 deadline)");

    function _teleportSig(address from, uint256 amount, uint256 deadline, bytes32 r, bytes32 s, uint8 v) internal {
        require(_checkDeadline(deadline), "Bridge: Signature expired");
        bytes32 structHash = keccak256(abi.encode(TELEPORT_TYPEHASH, from, amount, nonce(), deadline));

        bytes32 digest = _hashTypedDataV4(structHash);

        address signer = ECDSA.recover(digest, v, r, s);

        require(signer == from, "Bridge: Invalid signature");

        _teleport(from, address(this), amount);
    }

    /**
     * @dev Claims tokens from the bridge contract.
     * @param to The address of the user who will receive the tokens.
     * @param amount The amount of tokens to claim.
     * @param otherChainNonce The nonce of the teleport on the other chain.
     * @param signatures The signatures of the backend signers.
     */
    function _claimSig(
        address to,
        uint256 amount,
        uint256 otherChainNonce,
        SignatureWithDeadline[] calldata signatures
    ) internal {
        bytes32[] memory digests = new bytes32[](signatures.length);

        for (uint256 id = 0; id < signatures.length; id++) {
            digests[id] = _getClaimTypehash(to, amount, otherChainNonce, signatures[id].deadline);
        }

        _checkSignatures(digests, signatures);

        _claim(to, amount, otherChainNonce);
    }

    /**
     * @dev Gets typehash of the claim request.
     * @param to The address of the user who will receive the tokens.
     * @param amount The amount of tokens to claim.
     * @param nonce The nonce of the claim.
     * @param deadline The deadline of the signature.
     */
    function _getClaimTypehash(
        address to,
        uint256 amount,
        uint256 nonce,
        uint256 deadline
    ) internal view returns (bytes32) {
        bytes32 structHash = keccak256(abi.encode(CLAIM_TYPEHASH, to, amount, nonce, deadline));
        bytes32 digest = _hashTypedDataV4(structHash);
        return digest;
    }
}

// File: contracts/kale-bridge-v2/BridgeTransfer.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Counters.sol";

abstract contract BridgeTransfer {
    // Strange layout to use less storage slots (3 instead of 4/5)
    struct TeleportInfo {
        uint64 timestamp;
        address from;
        uint64 nonce;
        address to;
        uint256 amount;
    }

    using SafeERC20 for IERC20;
    using Counters for Counters.Counter;

    // The token to teleport.
    IERC20 public immutable token;
    // The minimum amount of tokens to teleport.
    uint256 public minTeleportAmount;
    // Nonce for teleporting tokens to the bridge contract.
    Counters.Counter private _teleportNonce;
    // Nonces for claiming tokens from the bridge contract.
    mapping(uint256 => bool) public processedNonces;
    // Teleport info for each teleport.
    mapping(uint256 => TeleportInfo) public teleports;

    event Teleport(address indexed from, address indexed to, uint amount, uint indexed nonce);
    event Claimed(address indexed from, address indexed to, uint amount, uint indexed nonce);
    event MinTeleportAmountChanged(address changer, uint amount);

    constructor(address _token) {
        require(_token != address(0), "Bridge: token address is zero");
        token = IERC20(_token);
    }

    /**
     * @dev Returns the current teleport nonce.
     */
    function nonce() public view returns (uint) {
        return _teleportNonce.current();
    }

    /**
     * @dev Teleports tokens from the user to the bridge contract.
     * @param from The address of the user who will send the tokens.
     * @param to The address of the user who will receive the tokens.
     * @param amount The amount of tokens to teleport.
     */
    function _teleport(address from, address to, uint amount) internal {
        uint256 currentNonce = _teleportNonce.current();

        emit Teleport(from, to, amount, currentNonce);

        teleports[currentNonce] = TeleportInfo({
            timestamp: uint64(block.timestamp),
            from: from,
            nonce: uint64(currentNonce),
            to: to,
            amount: amount
        });

        token.safeTransferFrom(from, to, amount);

        _teleportNonce.increment();
    }

    /**
     * @dev Claims tokens from the bridge contract.
     * @param to The address of the user who will receive the tokens.
     * @param amount The amount of tokens to claim.
     * @param otherChainNonce The nonce of the teleport on the other chain.
     */
    function _claim(address to, uint amount, uint otherChainNonce) internal {
        require(!processedNonces[otherChainNonce], "Bridge: nonce already processed");
        processedNonces[otherChainNonce] = true;

        token.safeTransfer(to, amount);

        emit Claimed(address(this), to, amount, otherChainNonce);
    }

    /**
     * @dev Changes the minimum amount of tokens to teleport.
     * @param amount The minimum amount of tokens to teleport.
     */
    function _setMinTeleportAmount(uint256 amount) internal {
        ERC20 _token = ERC20(address(token));
        uint256 _minTeleportAmount = amount * (10 ** _token.decimals());
        emit MinTeleportAmountChanged(msg.sender, _minTeleportAmount);
        minTeleportAmount = _minTeleportAmount;
    }
}

// File: contracts/kale-bridge-v2/BridgeUserBlocklist.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

import "@openzeppelin/contracts/access/Ownable.sol";

import "../blocklist/extensions/UserBlocklist.sol";
import "./BridgeRoles.sol";

abstract contract BridgeUserBlocklist is BridgeRoles, UserBlocklist {
    /**
     * @inheritdoc IERC165
     */
    function supportsInterface(
        bytes4 interfaceId
    ) public view virtual override(AccessControl, UserBlocklist) returns (bool) {
        return AccessControl.supportsInterface(interfaceId) || UserBlocklist.supportsInterface(interfaceId);
    }

    string internal constant USERBLOCK_MESSAGE = "Bridge: Action is blocked for";

    constructor(address blocklist_) UserBlocklist(blocklist_) {
        if (blocklist_ == address(0)) {
            _changeBlocklistState(false);
        }
    }

    function changeBlocklistState(bool state) external onlyAdmin {
        _changeBlocklistState(state);
    }

    function setBlocklist(address blocklist_) external onlyOwner {
        _setBlocklist(blocklist_);
    }

    modifier userIsNotBlocked(address user) {
        _checkIfActionIsAllowed(user, USERBLOCK_MESSAGE);
        _;
    }
}