Contract Source Code:

// SPDX-License-Identifier: MIT
pragma solidity 0.8.23;
pragma abicoder v2;

import { AccessControlDefaultAdminRules } from "@openzeppelin/contracts/access/AccessControlDefaultAdminRules.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { ReentrancyGuard } from "@openzeppelin/contracts/security/ReentrancyGuard.sol";

import "../vesting/TokenVesting.sol";

contract FairAuctionVesting is ReentrancyGuard, AccessControlDefaultAdminRules {
    using SafeERC20 for IERC20;

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

    /// @notice The contribution and claim status of each user
    struct UserInfo {
        uint256 contribution; // amount taken into account to obtain TOKEN
        bool hasClaimed; // has already claimed its contribution
    }

    /// @notice BIO's main token contract
    IERC20 public immutable BIO_TOKEN;

    /// @notice The BIO vesting contract
    TokenVesting public immutable VBIO_TOKEN;

    /// @notice The DAO token used to participate in the swap
    IERC20 public immutable DAO_TOKEN;

    /// @notice The start time of the swap period
    uint256 public immutable START_TIME;

    /// @notice The end time of the swap period
    uint256 public immutable END_TIME;

    /// @notice The information about each swaper
    mapping(address => UserInfo) public userInfo;

    /// @notice The total amount swapped
    uint256 public totalRaised;

    /// @notice The maximum amount of BIO_TOKEN to distribute during the sale
    uint256 public immutable MAX_BIO_TO_DISTRIBUTE;

    /// @notice The maximum amount of VBIO_TOKEN to distribute during the sale
    uint256 public immutable MAX_VBIO_TO_DISTRIBUTE;

    /// @notice The minimum amount to raise to distribute the maximum amount of BIO and vBIO
    uint256 public immutable MIN_DAO_RAISED_FOR_MAX_BIO;

    /// @notice The maximum amount to raise to distribute the maximum amount of BIO and vBIO
    uint256 public immutable MAX_DAO_RAISE;

    /// @notice The treasury multisig, which will receive the swaps
    address public immutable treasury;

    /// @notice Whether unsold tokens have been withdrawn
    bool public unsoldTokensWithdrew;

    /// @notice Whether the claim period is enabled
    bool public claimEnabled;

    /// @notice Whether the sale is paused
    bool public isPaused;

    // Parameters for vestingSchedule setups on vBIO
    /// @notice The cliff period for vesting
    uint256 public vestingCliff;
    /// @notice The start time for vesting
    uint256 public vestingStart;
    /// @notice The duration of the vesting period
    uint256 public vestingDuration = 365 days;
    /// @notice The number of slices per second for vesting
    uint256 public vestingSlicePerSecond = 1;
    /// @notice Whether the vesting is revocable
    bool public vestingIsRevocable = false;

    /**
     * @notice Constructor for the FairAuctionVesting contract.
     * @param bioToken_ The address of the BIO token contract.
     * @param vbioToken_ The address of the VBIO token vesting contract.
     * @param daoToken_ The address of the DAO token contract used to swap.
     * @param startTime_ The start time of the sale.
     * @param endTime_ The end time of the sale.
     * @param treasury_ The address of the treasury multisig, which will receive the raised amount.
     * @param maxToDistribute_ The maximum amount of BIO tokens to distribute during the sale.
     * @param maxToDistribute2_ The maximum amount of VBIO tokens to distribute during the sale.
     * @param minToRaise_ The minimum amount to raise for maximum BIO token distribution.
     *
     * Reverts if the start time is later than or equal to the end time, if the treasury address is the zero address,
     * or if the BIO or VBIO token addresses are the zero address. Vesting start time is set to the end time of the swap period.
     */
    constructor(
        IERC20 bioToken_,
        TokenVesting vbioToken_,
        IERC20 daoToken_,
        uint256 startTime_,
        uint256 endTime_,
        address treasury_,
        uint256 maxToDistribute_,
        uint256 maxToDistribute2_,
        uint256 minToRaise_,
        uint256 maxToRaise_
    ) AccessControlDefaultAdminRules(0, msg.sender) {
        if (startTime_ < block.timestamp) revert InvalidConstructorParameters();
        if (startTime_ >= endTime_) revert InvalidConstructorParameters();
        if (treasury_ == address(0)) revert InvalidConstructorParameters();
        if (address(bioToken_) == address(0)) revert InvalidConstructorParameters();
        if (address(vbioToken_) == address(0)) revert InvalidConstructorParameters();
        if (address(daoToken_) == address(0)) revert InvalidConstructorParameters();

        BIO_TOKEN = bioToken_;
        VBIO_TOKEN = vbioToken_;
        DAO_TOKEN = daoToken_;
        START_TIME = startTime_;
        END_TIME = endTime_;
        vestingStart = endTime_;
        treasury = treasury_;
        MAX_BIO_TO_DISTRIBUTE = maxToDistribute_;
        MAX_VBIO_TO_DISTRIBUTE = maxToDistribute2_;
        MIN_DAO_RAISED_FOR_MAX_BIO = minToRaise_;
        if (maxToRaise_ == 0) {
            maxToRaise_ = type(uint256).max;
        }
        MAX_DAO_RAISE = maxToRaise_;
    }

    /**
     * EVENTS
     */
    event Swap(address indexed user, uint256 amount);
    event Claim(address indexed user, uint256 amount, uint256 amount2);
    event EmergencyWithdraw(address token, uint256 amount);
    event SetPause(bool status);

    /**
     * ERRORS
     */

    /// @dev This error is fired when trying to perform an action that is not
    /// supported by the contract, like transfers and approvals. These actions
    /// will never be supported.
    error InvalidConstructorParameters();
    error SaleInactive();
    error SaleNotFilled();
    error SalePause();
    error SaleNotEnded();
    error SaleNotClaimable();
    error ZeroAmount();
    error ZeroContribution();
    error AlreadyClaimed();
    error TokensAlreadyWithdrawn();
    error TransferFailed();
    error InvalidScheduleParameter();
    error SaleStarted();
    error CapReached();
    error MinRaiseReached();

    /**
     * MODIFIERS
     */

    /**
     * @dev Check whether the sale is currently active
     *
     * Will be marked as inactive if BIO_TOKEN has not been swapped into the contract
     */
    modifier isSaleActive() {
        if (!hasStarted() || hasEnded()) revert SaleInactive();
        if (BIO_TOKEN.balanceOf(address(this)) < (MAX_BIO_TO_DISTRIBUTE + MAX_VBIO_TO_DISTRIBUTE)) revert SaleNotFilled();
        // check if this contract has vesting creator role
        if (!VBIO_TOKEN.hasRole(VBIO_TOKEN.VESTING_CREATOR_ROLE(), address(this))) revert SaleNotFilled();
        if (totalRaised >= MAX_DAO_RAISE) revert CapReached();
        _;
    }

    /**
     * @dev Check whether the sale is currently paused
     */
    modifier isNotPaused() {
        if (isPaused) revert SalePause();
        _;
    }

    /**
     * @dev Check whether users can claim their purchased BIO_TOKEN
     *
     * If sale has not ended but the cap is reached and claim is enabled, users can claim their tokens
     * If sale has ended
     */
    modifier isClaimable() {
        if (!hasEnded() && totalRaised < MAX_DAO_RAISE) revert SaleNotEnded();
        if (!claimEnabled) revert SaleNotClaimable();
        _;
    }

    /**
     * PUBLIC VIEWS
     */

    /**
     * @dev Get remaining duration before the end of the sale
     */
    function getRemainingTime() external view returns (uint256) {
        if (hasEnded()) return 0;
        return END_TIME - _currentBlockTimestamp();
    }

    /**
     * @dev Returns whether the sale has already started
     */
    function hasStarted() public view returns (bool) {
        return _currentBlockTimestamp() >= START_TIME;
    }

    /**
     * @dev Returns whether the sale has already ended
     */
    function hasEnded() public view returns (bool) {
        return END_TIME <= _currentBlockTimestamp();
    }

    /**
     * @dev Returns the amount of BIO_TOKEN to be distributed based on the current total raised
     */
    function bioToDistribute() public view returns (uint256) {
        if (MIN_DAO_RAISED_FOR_MAX_BIO > totalRaised) {
            return MAX_BIO_TO_DISTRIBUTE * totalRaised / MIN_DAO_RAISED_FOR_MAX_BIO;
        }
        return MAX_BIO_TO_DISTRIBUTE;
    }

    /**
     * @dev Returns the amount of VBIO_TOKEN to be distributed based on the current total raised
     */
    function vbioToDistribute() public view returns (uint256) {
        if (MIN_DAO_RAISED_FOR_MAX_BIO > totalRaised) {
            return MAX_VBIO_TO_DISTRIBUTE * totalRaised / MIN_DAO_RAISED_FOR_MAX_BIO;
        }
        return MAX_VBIO_TO_DISTRIBUTE;
    }

    /**
     * @dev Returns the amount of BIO_TOKEN + VBIO_TOKEN to be distributed based on the current total raised
     */
    function tokensToDistribute() public view returns (uint256) {
        return bioToDistribute() + vbioToDistribute();
    }

    /**
     * @dev Get user tokens amount to claim
     */
    function getExpectedClaimAmount(address account) public view returns (uint256 bioTokenAmount, uint256 vbioTokenAmount) {
        if (totalRaised == 0) return (0, 0);

        UserInfo memory user = userInfo[account];
        bioTokenAmount = user.contribution * bioToDistribute() / totalRaised;
        vbioTokenAmount = user.contribution * vbioToDistribute() / totalRaised;
    }

    /**
     * @dev Purchase a contribution for the sale for a value of "amount" DAO_TOKEN
     */
    function swap(uint256 amount) external isSaleActive isNotPaused nonReentrant {
        if (amount == 0) revert ZeroAmount();
        
        // If the user tries to swap more than the remaining amount, 
        // we will swap the remaining amount
        if (MAX_DAO_RAISE - totalRaised < amount) {
            amount = MAX_DAO_RAISE - totalRaised;
        } 

        // Update user information and total raised
        UserInfo storage user = userInfo[msg.sender];
        user.contribution = user.contribution + amount;
        totalRaised = totalRaised + amount;

        // Emit an event for the purchase
        emit Swap(msg.sender, amount);

        // Transfer DAO_TOKEN directly from the sender to the treasury
        DAO_TOKEN.safeTransferFrom(msg.sender, treasury, amount);
    }

    /**
     * @dev Claim purchased BIO_TOKEN during the sale
     */
    function claim() external nonReentrant isClaimable {
        UserInfo storage user = userInfo[msg.sender];

        if (totalRaised == 0 || user.contribution == 0) revert ZeroContribution();
        if (user.hasClaimed) revert AlreadyClaimed();

        (uint256 bioAmount, uint256 vbioAmount) = getExpectedClaimAmount(msg.sender);

        uint256 contractBalance = BIO_TOKEN.balanceOf(address(this));
        uint256 totalRequired = bioAmount + vbioAmount;

        // Check if the contract has enough BIO_TOKEN for the claim
        if (totalRequired > contractBalance) revert TransferFailed();

        user.hasClaimed = true;

        emit Claim(msg.sender, bioAmount, vbioAmount);

        // Transfer BIO_TOKEN to the user
        if (bioAmount > 0) {
            bool bioTransferSuccess = BIO_TOKEN.transfer(msg.sender, bioAmount);
            if (!bioTransferSuccess) revert TransferFailed();
        }

        // Transfer BIO_TOKEN to the VBIO_TOKEN contract and create vesting schedule
        if (vbioAmount > 0) {
            bool vbioTransferSuccess = BIO_TOKEN.transfer(address(VBIO_TOKEN), vbioAmount);
            if (!vbioTransferSuccess) revert TransferFailed();
            VBIO_TOKEN.createVestingSchedule(
                msg.sender, vestingStart, vestingCliff, vestingDuration, vestingSlicePerSecond, vestingIsRevocable, vbioAmount
            );
        }
    }

    /**
     * OWNABLE FUNCTIONS
     */
    function setPause(bool value) external onlyRole(PAUSER_ROLE) {
        isPaused = value;
        emit SetPause(value);
    }

    /**
     * @dev Withdraw unsold BIO_TOKEN + VBIO_TOKEN if MIN_DAO_RAISED_FOR_MAX_BIO has not been reached
     *
     * Must only be called by the Admin
     */
    function withdrawUnsoldTokens() external onlyRole(DEFAULT_ADMIN_ROLE) {
        if (!hasEnded()) revert SaleNotEnded();
        if (totalRaised >= MIN_DAO_RAISED_FOR_MAX_BIO) revert MinRaiseReached();
        if (unsoldTokensWithdrew) revert TokensAlreadyWithdrawn();

        uint256 totalBIOSold = bioToDistribute();
        uint256 totalVBIOSold = vbioToDistribute();

        unsoldTokensWithdrew = true;
        //because VBIO is BIO and is sent to VBIO contract before claiming
        BIO_TOKEN.transfer(treasury, MAX_BIO_TO_DISTRIBUTE + MAX_VBIO_TO_DISTRIBUTE - totalBIOSold - totalVBIOSold);
    }

    // setters

    function setVestingStart(uint256 start_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _start should be no further away than 30 weeks
        if (start_ > block.timestamp + 30 weeks) revert InvalidScheduleParameter();
        vestingStart = start_;
    }

    function setCliff(uint256 cliff_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _duration must be longer than _cliff
        if (vestingDuration < cliff_) revert InvalidScheduleParameter();
        vestingCliff = cliff_;
    }

    function setDuration(uint256 duration_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _duration should be at least 7 days and max 50 years
        if (duration_ < 7 days || duration_ > 50 * (365 days)) revert InvalidScheduleParameter();
        vestingDuration = duration_;
    }

    function setSlicePerSecond(uint256 slicePerSecond_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _slicePeriodSeconds should be between 1 and 60 seconds
        if (slicePerSecond_ == 0 || slicePerSecond_ > 60) revert InvalidScheduleParameter();
        vestingSlicePerSecond = slicePerSecond_;
    }

    function setIsRevocable(bool isRevocable_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        vestingIsRevocable = isRevocable_;
    }

    /**
     * /!\ EMERGENCY ONLY
     */

    /**
     * @dev Failsafe
     */
    function emergencyWithdrawFunds(address token, uint256 amount) external onlyRole(DEFAULT_ADMIN_ROLE) {
        IERC20(token).safeTransfer(treasury, amount);

        emit EmergencyWithdraw(token, amount);
    }

    /**
     * @dev Failsafe
     */
    function emergencyWithdrawBIO() external onlyRole(DEFAULT_ADMIN_ROLE) {
        uint256 amount = BIO_TOKEN.balanceOf(address(this));
        BIO_TOKEN.safeTransfer(treasury, amount);

        emit EmergencyWithdraw(address(BIO_TOKEN), amount);
    }

    function enableClaim() external onlyRole(DEFAULT_ADMIN_ROLE) {
        claimEnabled = true;
    }

    /**
     * INTERNAL FUNCTIONS
     */

    /**
     * @dev Utility function to get the current block timestamp
     */
    function _currentBlockTimestamp() internal view virtual returns (uint256) {
        return block.timestamp;
    }
}

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

pragma solidity ^0.8.0;

import "./AccessControl.sol";
import "./IAccessControlDefaultAdminRules.sol";
import "../utils/math/SafeCast.sol";
import "../interfaces/IERC5313.sol";

/**
 * @dev Extension of {AccessControl} that allows specifying special rules to manage
 * the `DEFAULT_ADMIN_ROLE` holder, which is a sensitive role with special permissions
 * over other roles that may potentially have privileged rights in the system.
 *
 * If a specific role doesn't have an admin role assigned, the holder of the
 * `DEFAULT_ADMIN_ROLE` will have the ability to grant it and revoke it.
 *
 * This contract implements the following risk mitigations on top of {AccessControl}:
 *
 * * Only one account holds the `DEFAULT_ADMIN_ROLE` since deployment until it's potentially renounced.
 * * Enforces a 2-step process to transfer the `DEFAULT_ADMIN_ROLE` to another account.
 * * Enforces a configurable delay between the two steps, with the ability to cancel before the transfer is accepted.
 * * The delay can be changed by scheduling, see {changeDefaultAdminDelay}.
 * * It is not possible to use another role to manage the `DEFAULT_ADMIN_ROLE`.
 *
 * Example usage:
 *
 * ```solidity
 * contract MyToken is AccessControlDefaultAdminRules {
 *   constructor() AccessControlDefaultAdminRules(
 *     3 days,
 *     msg.sender // Explicit initial `DEFAULT_ADMIN_ROLE` holder
 *    ) {}
 * }
 * ```
 *
 * _Available since v4.9._
 */
abstract contract AccessControlDefaultAdminRules is IAccessControlDefaultAdminRules, IERC5313, AccessControl {
    // pending admin pair read/written together frequently
    address private _pendingDefaultAdmin;
    uint48 private _pendingDefaultAdminSchedule; // 0 == unset

    uint48 private _currentDelay;
    address private _currentDefaultAdmin;

    // pending delay pair read/written together frequently
    uint48 private _pendingDelay;
    uint48 private _pendingDelaySchedule; // 0 == unset

    /**
     * @dev Sets the initial values for {defaultAdminDelay} and {defaultAdmin} address.
     */
    constructor(uint48 initialDelay, address initialDefaultAdmin) {
        require(initialDefaultAdmin != address(0), "AccessControl: 0 default admin");
        _currentDelay = initialDelay;
        _grantRole(DEFAULT_ADMIN_ROLE, initialDefaultAdmin);
    }

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

    /**
     * @dev See {IERC5313-owner}.
     */
    function owner() public view virtual returns (address) {
        return defaultAdmin();
    }

    ///
    /// Override AccessControl role management
    ///

    /**
     * @dev See {AccessControl-grantRole}. Reverts for `DEFAULT_ADMIN_ROLE`.
     */
    function grantRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        require(role != DEFAULT_ADMIN_ROLE, "AccessControl: can't directly grant default admin role");
        super.grantRole(role, account);
    }

    /**
     * @dev See {AccessControl-revokeRole}. Reverts for `DEFAULT_ADMIN_ROLE`.
     */
    function revokeRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        require(role != DEFAULT_ADMIN_ROLE, "AccessControl: can't directly revoke default admin role");
        super.revokeRole(role, account);
    }

    /**
     * @dev See {AccessControl-renounceRole}.
     *
     * For the `DEFAULT_ADMIN_ROLE`, it only allows renouncing in two steps by first calling
     * {beginDefaultAdminTransfer} to the `address(0)`, so it's required that the {pendingDefaultAdmin} schedule
     * has also passed when calling this function.
     *
     * After its execution, it will not be possible to call `onlyRole(DEFAULT_ADMIN_ROLE)` functions.
     *
     * NOTE: Renouncing `DEFAULT_ADMIN_ROLE` will leave the contract without a {defaultAdmin},
     * thereby disabling any functionality that is only available for it, and the possibility of reassigning a
     * non-administrated role.
     */
    function renounceRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        if (role == DEFAULT_ADMIN_ROLE && account == defaultAdmin()) {
            (address newDefaultAdmin, uint48 schedule) = pendingDefaultAdmin();
            require(
                newDefaultAdmin == address(0) && _isScheduleSet(schedule) && _hasSchedulePassed(schedule),
                "AccessControl: only can renounce in two delayed steps"
            );
            delete _pendingDefaultAdminSchedule;
        }
        super.renounceRole(role, account);
    }

    /**
     * @dev See {AccessControl-_grantRole}.
     *
     * For `DEFAULT_ADMIN_ROLE`, it only allows granting if there isn't already a {defaultAdmin} or if the
     * role has been previously renounced.
     *
     * NOTE: Exposing this function through another mechanism may make the `DEFAULT_ADMIN_ROLE`
     * assignable again. Make sure to guarantee this is the expected behavior in your implementation.
     */
    function _grantRole(bytes32 role, address account) internal virtual override {
        if (role == DEFAULT_ADMIN_ROLE) {
            require(defaultAdmin() == address(0), "AccessControl: default admin already granted");
            _currentDefaultAdmin = account;
        }
        super._grantRole(role, account);
    }

    /**
     * @dev See {AccessControl-_revokeRole}.
     */
    function _revokeRole(bytes32 role, address account) internal virtual override {
        if (role == DEFAULT_ADMIN_ROLE && account == defaultAdmin()) {
            delete _currentDefaultAdmin;
        }
        super._revokeRole(role, account);
    }

    /**
     * @dev See {AccessControl-_setRoleAdmin}. Reverts for `DEFAULT_ADMIN_ROLE`.
     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual override {
        require(role != DEFAULT_ADMIN_ROLE, "AccessControl: can't violate default admin rules");
        super._setRoleAdmin(role, adminRole);
    }

    ///
    /// AccessControlDefaultAdminRules accessors
    ///

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function defaultAdmin() public view virtual returns (address) {
        return _currentDefaultAdmin;
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function pendingDefaultAdmin() public view virtual returns (address newAdmin, uint48 schedule) {
        return (_pendingDefaultAdmin, _pendingDefaultAdminSchedule);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function defaultAdminDelay() public view virtual returns (uint48) {
        uint48 schedule = _pendingDelaySchedule;
        return (_isScheduleSet(schedule) && _hasSchedulePassed(schedule)) ? _pendingDelay : _currentDelay;
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function pendingDefaultAdminDelay() public view virtual returns (uint48 newDelay, uint48 schedule) {
        schedule = _pendingDelaySchedule;
        return (_isScheduleSet(schedule) && !_hasSchedulePassed(schedule)) ? (_pendingDelay, schedule) : (0, 0);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function defaultAdminDelayIncreaseWait() public view virtual returns (uint48) {
        return 5 days;
    }

    ///
    /// AccessControlDefaultAdminRules public and internal setters for defaultAdmin/pendingDefaultAdmin
    ///

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function beginDefaultAdminTransfer(address newAdmin) public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _beginDefaultAdminTransfer(newAdmin);
    }

    /**
     * @dev See {beginDefaultAdminTransfer}.
     *
     * Internal function without access restriction.
     */
    function _beginDefaultAdminTransfer(address newAdmin) internal virtual {
        uint48 newSchedule = SafeCast.toUint48(block.timestamp) + defaultAdminDelay();
        _setPendingDefaultAdmin(newAdmin, newSchedule);
        emit DefaultAdminTransferScheduled(newAdmin, newSchedule);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function cancelDefaultAdminTransfer() public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _cancelDefaultAdminTransfer();
    }

    /**
     * @dev See {cancelDefaultAdminTransfer}.
     *
     * Internal function without access restriction.
     */
    function _cancelDefaultAdminTransfer() internal virtual {
        _setPendingDefaultAdmin(address(0), 0);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function acceptDefaultAdminTransfer() public virtual {
        (address newDefaultAdmin, ) = pendingDefaultAdmin();
        require(_msgSender() == newDefaultAdmin, "AccessControl: pending admin must accept");
        _acceptDefaultAdminTransfer();
    }

    /**
     * @dev See {acceptDefaultAdminTransfer}.
     *
     * Internal function without access restriction.
     */
    function _acceptDefaultAdminTransfer() internal virtual {
        (address newAdmin, uint48 schedule) = pendingDefaultAdmin();
        require(_isScheduleSet(schedule) && _hasSchedulePassed(schedule), "AccessControl: transfer delay not passed");
        _revokeRole(DEFAULT_ADMIN_ROLE, defaultAdmin());
        _grantRole(DEFAULT_ADMIN_ROLE, newAdmin);
        delete _pendingDefaultAdmin;
        delete _pendingDefaultAdminSchedule;
    }

    ///
    /// AccessControlDefaultAdminRules public and internal setters for defaultAdminDelay/pendingDefaultAdminDelay
    ///

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function changeDefaultAdminDelay(uint48 newDelay) public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _changeDefaultAdminDelay(newDelay);
    }

    /**
     * @dev See {changeDefaultAdminDelay}.
     *
     * Internal function without access restriction.
     */
    function _changeDefaultAdminDelay(uint48 newDelay) internal virtual {
        uint48 newSchedule = SafeCast.toUint48(block.timestamp) + _delayChangeWait(newDelay);
        _setPendingDelay(newDelay, newSchedule);
        emit DefaultAdminDelayChangeScheduled(newDelay, newSchedule);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function rollbackDefaultAdminDelay() public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _rollbackDefaultAdminDelay();
    }

    /**
     * @dev See {rollbackDefaultAdminDelay}.
     *
     * Internal function without access restriction.
     */
    function _rollbackDefaultAdminDelay() internal virtual {
        _setPendingDelay(0, 0);
    }

    /**
     * @dev Returns the amount of seconds to wait after the `newDelay` will
     * become the new {defaultAdminDelay}.
     *
     * The value returned guarantees that if the delay is reduced, it will go into effect
     * after a wait that honors the previously set delay.
     *
     * See {defaultAdminDelayIncreaseWait}.
     */
    function _delayChangeWait(uint48 newDelay) internal view virtual returns (uint48) {
        uint48 currentDelay = defaultAdminDelay();

        // When increasing the delay, we schedule the delay change to occur after a period of "new delay" has passed, up
        // to a maximum given by defaultAdminDelayIncreaseWait, by default 5 days. For example, if increasing from 1 day
        // to 3 days, the new delay will come into effect after 3 days. If increasing from 1 day to 10 days, the new
        // delay will come into effect after 5 days. The 5 day wait period is intended to be able to fix an error like
        // using milliseconds instead of seconds.
        //
        // When decreasing the delay, we wait the difference between "current delay" and "new delay". This guarantees
        // that an admin transfer cannot be made faster than "current delay" at the time the delay change is scheduled.
        // For example, if decreasing from 10 days to 3 days, the new delay will come into effect after 7 days.
        return
            newDelay > currentDelay
                ? uint48(Math.min(newDelay, defaultAdminDelayIncreaseWait())) // no need to safecast, both inputs are uint48
                : currentDelay - newDelay;
    }

    ///
    /// Private setters
    ///

    /**
     * @dev Setter of the tuple for pending admin and its schedule.
     *
     * May emit a DefaultAdminTransferCanceled event.
     */
    function _setPendingDefaultAdmin(address newAdmin, uint48 newSchedule) private {
        (, uint48 oldSchedule) = pendingDefaultAdmin();

        _pendingDefaultAdmin = newAdmin;
        _pendingDefaultAdminSchedule = newSchedule;

        // An `oldSchedule` from `pendingDefaultAdmin()` is only set if it hasn't been accepted.
        if (_isScheduleSet(oldSchedule)) {
            // Emit for implicit cancellations when another default admin was scheduled.
            emit DefaultAdminTransferCanceled();
        }
    }

    /**
     * @dev Setter of the tuple for pending delay and its schedule.
     *
     * May emit a DefaultAdminDelayChangeCanceled event.
     */
    function _setPendingDelay(uint48 newDelay, uint48 newSchedule) private {
        uint48 oldSchedule = _pendingDelaySchedule;

        if (_isScheduleSet(oldSchedule)) {
            if (_hasSchedulePassed(oldSchedule)) {
                // Materialize a virtual delay
                _currentDelay = _pendingDelay;
            } else {
                // Emit for implicit cancellations when another delay was scheduled.
                emit DefaultAdminDelayChangeCanceled();
            }
        }

        _pendingDelay = newDelay;
        _pendingDelaySchedule = newSchedule;
    }

    ///
    /// Private helpers
    ///

    /**
     * @dev Defines if an `schedule` is considered set. For consistency purposes.
     */
    function _isScheduleSet(uint48 schedule) private pure returns (bool) {
        return schedule != 0;
    }

    /**
     * @dev Defines if an `schedule` is considered passed. For consistency purposes.
     */
    function _hasSchedulePassed(uint48 schedule) private view returns (bool) {
        return schedule < block.timestamp;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
    }

    function _nonReentrantAfter() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
     * `nonReentrant` function in the call stack.
     */
    function _reentrancyGuardEntered() internal view returns (bool) {
        return _status == _ENTERED;
    }
}

// contracts/TokenVesting.sol
// SPDX-License-Identifier: Apache-2.0
pragma solidity 0.8.23;

import { IERC20Metadata } from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import { AccessControlDefaultAdminRules } from "@openzeppelin/contracts/access/AccessControlDefaultAdminRules.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { ReentrancyGuard } from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import { Pausable } from "@openzeppelin/contracts/security/Pausable.sol";

/// @title TokenVesting - On-Chain vesting scheme enabled by smart contracts.
/// The TokenVesting contract can release its token balance gradually like a
/// typical vesting scheme, with a cliff and vesting period. The contract owner
/// can create vesting schedules for different users, even multiple for the same person.
/// Vesting schedules are optionally revokable by the owner. Additionally the
/// smart contract functions as an ERC20 compatible non-transferable virtual
/// token which can be used e.g. for governance.
/// This work is based on the TokenVesting contract by schmackofant
/// (https://github.com/moleculeprotocol/token-vesting-contract/)
/// and was extended to support the purchasing of vesting schedules and tokens for tax reasons
/// @author ElliottAnastassios (MTX Studio) - [email protected]
/// @author clepp (MTX Studio) - [email protected]
/// @author Schmackofant - [email protected]

contract TokenVesting is IERC20Metadata, ReentrancyGuard, Pausable, AccessControlDefaultAdminRules {
    using SafeERC20 for IERC20Metadata;

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

    /// VARIABLES ///

    /**
     * @notice The ERC20 name of the virtual token
     */
    string public override name;

    /**
     * @notice The ERC20 symbol of the virtual token
     */
    string public override symbol;

    /**
     * @notice address of the ERC20 underlying Token
     */
    IERC20Metadata public immutable underlyingToken;

    /**
     * @notice The ERC20 number of decimals of the virtual token
     * @dev This contract only supports underlying Token with 18 decimals
     */
    uint8 public constant override decimals = 18;

    /**
     * @notice total amount of base tokens in all vesting schedules
     */
    uint256 internal vestingSchedulesTotalAmount;

    enum Status {
        INVALID, //0
        INITIALIZED,
        REVOKED
    }

    /// STRUCTS ///

    /**
     * @dev vesting schedule struct
     * @param cliff cliff period in seconds
     * @param start start time of the vesting period
     * @param duration duration of the vesting period in seconds
     * @param slicePeriodSeconds duration of a slice period for the vesting in seconds
     * @param amountTotal total amount of tokens to be released at the end of the vesting
     * @param released amount of tokens released so far
     * @param status schedule status (initialized, revoked)
     * @param beneficiary address of beneficiary of the vesting schedule
     * @param revokable whether or not the vesting is revokable
     */
    struct VestingSchedule {
        uint256 cliff;
        uint256 start;
        uint256 duration;
        uint256 slicePeriodSeconds;
        uint256 amountTotal;
        uint256 released;
        Status status;
        address beneficiary;
        bool revokable;
    }

    /// MAPPINGS ///

    /**
     * @dev This mapping is used to keep track of the vesting schedules
     */
    mapping(bytes32 => VestingSchedule) internal vestingSchedules;

    /**
     * @notice This mapping is used to keep track of the number of vesting schedules for each beneficiary
     */
    mapping(address => uint256) public holdersVestingScheduleCount;

    /**
     * @dev This mapping is used to keep track of the total amount of vested tokens for each beneficiary
     */
    mapping(address => uint256) internal holdersVestedAmount;

    /// EVENTS ///

    event ScheduleCreated(
        bytes32 indexed scheduleId,
        address indexed beneficiary,
        uint256 amount,
        uint256 start,
        uint256 cliff,
        uint256 duration,
        uint256 slicePeriodSeconds,
        bool revokable
    );
    event TokensReleased(bytes32 indexed scheduleId, address indexed beneficiary, uint256 amount);
    event ScheduleRevoked(bytes32 indexed scheduleId);

    /// MODIFIERS ///

    /**
     * @dev Reverts if the vesting schedule does not exist or has been revoked.
     */
    modifier onlyIfVestingScheduleNotRevoked(bytes32 vestingScheduleId) {
        // Check if schedule exists
        if (vestingSchedules[vestingScheduleId].duration == 0) revert InvalidSchedule();
        //slither-disable-next-line incorrect-equality
        if (vestingSchedules[vestingScheduleId].status == Status.REVOKED) revert ScheduleWasRevoked();
        _;
    }

    /// ERRORS ///

    /**
     * @dev This error is fired when trying to perform an action that is not
     * supported by the contract, like transfers and approvals. These actions
     * will never be supported.
     */
    error NotSupported();

    error DecimalsError();
    error InsufficientTokensInContract();
    error InsufficientReleasableTokens();
    error InvalidSchedule();
    error InvalidDuration();
    error InvalidAmount();
    error InvalidSlicePeriod();
    error InvalidStart();
    error DurationShorterThanCliff();
    error NotRevokable();
    error Unauthorized();
    error ScheduleWasRevoked();
    error TooManySchedulesForBeneficiary();
    error VestingScheduleCapacityReached();
    error InvalidAddress();

    /// CONSTRUCTOR ///

    /**
     * @notice Creates a vesting contract.
     * @param _underlyingToken address of the ERC20 base token contract
     * @param _name name of the virtual token
     * @param _symbol symbol of the virtual token
     */
    constructor(IERC20Metadata _underlyingToken, string memory _name, string memory _symbol, address _vestingCreator)
        AccessControlDefaultAdminRules(0, msg.sender)
    {
        underlyingToken = _underlyingToken;
        if (underlyingToken.decimals() != 18) revert DecimalsError();
        name = _name;
        symbol = _symbol;
        _grantRole(VESTING_CREATOR_ROLE, _vestingCreator);
    }

    /// FUNCTIONS ///

    /**
     * @dev All types of transfers are permanently disabled.
     */
    function transferFrom(address, address, uint256) public pure override returns (bool) {
        revert NotSupported();
    }

    /**
     * @dev All types of transfers are permanently disabled.
     */
    function transfer(address, uint256) public pure override returns (bool) {
        revert NotSupported();
    }

    /**
     * @dev All types of approvals are permanently disabled to reduce code size.
     */
    function approve(address, uint256) public pure override returns (bool) {
        revert NotSupported();
    }

    /**
     * @dev Approvals cannot be set, so allowances are always zero.
     */
    function allowance(address, address) public pure override returns (uint256) {
        return 0;
    }

    /**
     * @notice Returns the amount of virtual tokens in existence
     */
    function totalSupply() public view virtual override returns (uint256) {
        return vestingSchedulesTotalAmount;
    }

    /**
     * @notice Returns the sum of virtual tokens for a user
     * @param user The user for whom the balance is calculated
     * @return Balance of the user
     */
    function balanceOf(address user) public view virtual override returns (uint256) {
        return holdersVestedAmount[user];
    }

    /**
     * @notice Returns the vesting schedule information for a given holder and index.
     * @return the vesting schedule structure information
     */
    function getVestingScheduleByAddressAndIndex(address holder, uint256 index) external view returns (VestingSchedule memory) {
        return getVestingSchedule(computeVestingScheduleIdForAddressAndIndex(holder, index));
    }

    /**
     * @notice Public function for creating a vesting schedule.
     * @param _beneficiary address of the beneficiary to whom vested tokens are transferred
     * @param _start start time of the vesting period
     * @param _cliff duration in seconds of the cliff in which tokens will begin to vest
     * @param _duration duration in seconds of the period in which the tokens will vest
     * @param _slicePeriodSeconds duration of a slice period for the vesting in seconds
     * @param _revokable whether the vesting is revokable or not
     * @param _amount total amount of tokens to be released at the end of the vesting
     */
    function createVestingSchedule(
        address _beneficiary,
        uint256 _start,
        uint256 _cliff,
        uint256 _duration,
        uint256 _slicePeriodSeconds,
        bool _revokable,
        uint256 _amount
    ) external whenNotPaused onlyRole(VESTING_CREATOR_ROLE) {
        _createVestingSchedule(_beneficiary, _start, _cliff, _duration, _slicePeriodSeconds, _revokable, _amount);
    }

    /**
     * @notice Internal function for creating a vesting schedule.
     * @param _beneficiary address of the beneficiary to whom vested tokens are transferred
     * @param _start start time of the vesting period
     * @param _cliff duration in seconds of the cliff in which tokens will begin to vest
     * @param _duration duration in seconds of the period in which the tokens will vest
     * @param _slicePeriodSeconds duration of a slice period for the vesting in seconds
     * @param _revokable whether the vesting is revokable or not
     * @param _amount total amount of tokens to be released at the end of the vesting
     */
    function _createVestingSchedule(
        address _beneficiary,
        uint256 _start,
        uint256 _cliff,
        uint256 _duration,
        uint256 _slicePeriodSeconds,
        bool _revokable,
        uint256 _amount
    ) internal {
        if (getWithdrawableAmount() < _amount) revert InsufficientTokensInContract();

        // _start should be no further away than 30 weeks
        if (_start > block.timestamp + 30 weeks) revert InvalidStart();

        // _duration should be at least 7 days and max 50 years
        if (_duration < 7 days || _duration > 50 * (365 days)) revert InvalidDuration();

        if (_amount == 0 || _amount > 2 ** 200) revert InvalidAmount();

        // _slicePeriodSeconds should be between 1 and 60 seconds
        if (_slicePeriodSeconds == 0 || _slicePeriodSeconds > 60) revert InvalidSlicePeriod();

        // _duration must be longer than _cliff
        if (_duration < _cliff) revert DurationShorterThanCliff();

        if (holdersVestingScheduleCount[_beneficiary] >= 100) revert TooManySchedulesForBeneficiary();

        bytes32 vestingScheduleId = computeVestingScheduleIdForAddressAndIndex(_beneficiary, holdersVestingScheduleCount[_beneficiary]++);
        vestingSchedules[vestingScheduleId] =
            VestingSchedule(_start + _cliff, _start, _duration, _slicePeriodSeconds, _amount, 0, Status.INITIALIZED, _beneficiary, _revokable);
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount + _amount;

        holdersVestedAmount[_beneficiary] = holdersVestedAmount[_beneficiary] + _amount;
        emit ScheduleCreated(vestingScheduleId, _beneficiary, _amount, _start, _cliff, _duration, _slicePeriodSeconds, _revokable);
        emit Transfer(address(0), _beneficiary, _amount);
    }

    /**
     * @notice Revokes the vesting schedule for given identifier.
     * @param vestingScheduleId the vesting schedule identifier
     */
    function revoke(bytes32 vestingScheduleId) external onlyRole(DEFAULT_ADMIN_ROLE) onlyIfVestingScheduleNotRevoked(vestingScheduleId) {
        VestingSchedule storage vestingSchedule = vestingSchedules[vestingScheduleId];
        if (!vestingSchedule.revokable) revert NotRevokable();
        if (_computeReleasableAmount(vestingSchedule) > 0) {
            _release(vestingScheduleId, _computeReleasableAmount(vestingSchedule));
        }
        uint256 unreleased = vestingSchedule.amountTotal - vestingSchedule.released;
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount - unreleased;
        holdersVestedAmount[vestingSchedule.beneficiary] = holdersVestedAmount[vestingSchedule.beneficiary] - unreleased;
        vestingSchedule.status = Status.REVOKED;
        emit ScheduleRevoked(vestingScheduleId);
        emit Transfer(vestingSchedule.beneficiary, address(0), unreleased);
    }

    /**
     * @notice Pauses or unpauses the creation of new vesting schedules and the purchase of those vesting schedules
     * @param paused true if the creation of vesting schedules and purchase of those should be paused, false otherwise
     */
    function setPaused(bool paused) external onlyRole(DEFAULT_ADMIN_ROLE) {
        if (paused) {
            _pause();
        } else {
            _unpause();
        }
    }

    /**
     * @notice Withdraw the specified amount if possible.
     * @param amount the amount to withdraw
     */
    function withdraw(uint256 amount) external nonReentrant onlyRole(DEFAULT_ADMIN_ROLE) {
        if (amount > getWithdrawableAmount()) revert InsufficientTokensInContract();
        underlyingToken.safeTransfer(msg.sender, amount);
    }

    /**
     * @notice Internal function for releasing vested amount of tokens.
     * @param vestingScheduleId the vesting schedule identifier
     * @param amount the amount to release
     */
    function _release(bytes32 vestingScheduleId, uint256 amount) internal {
        VestingSchedule storage vestingSchedule = vestingSchedules[vestingScheduleId];
        bool isBeneficiary = msg.sender == vestingSchedule.beneficiary;
        bool isOwner = msg.sender == owner();
        if (!isBeneficiary && !isOwner) revert Unauthorized();
        if (amount > _computeReleasableAmount(vestingSchedule)) revert InsufficientReleasableTokens();
        vestingSchedule.released = vestingSchedule.released + amount;
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount - amount;
        holdersVestedAmount[vestingSchedule.beneficiary] = holdersVestedAmount[vestingSchedule.beneficiary] - amount;
        emit TokensReleased(vestingScheduleId, vestingSchedule.beneficiary, amount);
        underlyingToken.safeTransfer(vestingSchedule.beneficiary, amount);
        emit Transfer(vestingSchedule.beneficiary, address(0), amount);
    }

    /**
     * @notice Release vested amount of tokens.
     * @param vestingScheduleId the vesting schedule identifier
     * @param amount the amount to release
     */
    function release(bytes32 vestingScheduleId, uint256 amount) external nonReentrant onlyIfVestingScheduleNotRevoked(vestingScheduleId) {
        _release(vestingScheduleId, amount);
    }

    /**
     * @notice Release all available tokens for holder address
     * @param holder address of the holder & beneficiary
     */
    function releaseAvailableTokensForHolder(address holder) external nonReentrant {
        if (msg.sender != holder && msg.sender != owner()) revert Unauthorized();
        uint256 vestingScheduleCount = holdersVestingScheduleCount[holder];
        for (uint256 i = 0; i < vestingScheduleCount; i++) {
            bytes32 vestingScheduleId = computeVestingScheduleIdForAddressAndIndex(holder, i);
            uint256 releasable = _computeReleasableAmount(vestingSchedules[vestingScheduleId]);
            if (releasable > 0) {
                _release(vestingScheduleId, releasable);
            }
        }
    }

    /// GETTERS ///

    /**
     * @notice Computes the vested amount of tokens for the given vesting schedule identifier.
     * @return the vested amount
     */
    function computeReleasableAmount(bytes32 vestingScheduleId) external view onlyIfVestingScheduleNotRevoked(vestingScheduleId) returns (uint256) {
        return _computeReleasableAmount(vestingSchedules[vestingScheduleId]);
    }

    /**
     * @notice Returns the vesting schedule information for a given identifier.
     * @return the vesting schedule structure information
     */
    function getVestingSchedule(bytes32 vestingScheduleId) public view returns (VestingSchedule memory) {
        return vestingSchedules[vestingScheduleId];
    }

    /**
     * @notice Returns the amount of base tokens that can be withdrawn by the owner.
     * @return the amount of tokens
     */
    function getWithdrawableAmount() public view returns (uint256) {
        return underlyingToken.balanceOf(address(this)) - vestingSchedulesTotalAmount;
    }

    /**
     * @notice Computes the vesting schedule identifier for an address and an index.
     */
    function computeVestingScheduleIdForAddressAndIndex(address holder, uint256 index) public pure returns (bytes32) {
        return keccak256(abi.encodePacked(holder, index));
    }

    /**
     * @dev Computes the releasable amount of tokens for a vesting schedule.
     * @return the amount of releasable tokens
     */
    function _computeReleasableAmount(VestingSchedule storage vestingSchedule) internal view returns (uint256) {
        uint256 currentTime = block.timestamp;
        //slither-disable-next-line incorrect-equality
        if (currentTime < vestingSchedule.cliff || vestingSchedule.status == Status.REVOKED) {
            return 0;
        } else if (currentTime >= vestingSchedule.start + vestingSchedule.duration) {
            return vestingSchedule.amountTotal - vestingSchedule.released;
        } else {
            uint256 timeFromStart = currentTime - vestingSchedule.start;
            uint256 secondsPerSlice = vestingSchedule.slicePeriodSeconds;
            uint256 vestedSlicePeriods = timeFromStart / secondsPerSlice;
            // Disable warning: duration and token amounts are checked in schedule creation and prevent underflow/overflow
            //slither-disable-next-line divide-before-multiply
            uint256 vestedSeconds = vestedSlicePeriods * secondsPerSlice;
            // Disable warning: duration and token amounts are checked in schedule creation and prevent underflow/overflow
            //slither-disable-next-line divide-before-multiply
            uint256 vestedAmount = vestingSchedule.amountTotal * vestedSeconds / vestingSchedule.duration;
            return vestedAmount - vestingSchedule.released;
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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:
 *
 * ```solidity
 * 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}:
 *
 * ```solidity
 * 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. We recommend using {AccessControlDefaultAdminRules}
 * to enforce additional security measures for this role.
 */
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(account),
                        " 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());
        }
    }
}

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

pragma solidity ^0.8.0;

import "./IAccessControl.sol";

/**
 * @dev External interface of AccessControlDefaultAdminRules declared to support ERC165 detection.
 *
 * _Available since v4.9._
 */
interface IAccessControlDefaultAdminRules is IAccessControl {
    /**
     * @dev Emitted when a {defaultAdmin} transfer is started, setting `newAdmin` as the next
     * address to become the {defaultAdmin} by calling {acceptDefaultAdminTransfer} only after `acceptSchedule`
     * passes.
     */
    event DefaultAdminTransferScheduled(address indexed newAdmin, uint48 acceptSchedule);

    /**
     * @dev Emitted when a {pendingDefaultAdmin} is reset if it was never accepted, regardless of its schedule.
     */
    event DefaultAdminTransferCanceled();

    /**
     * @dev Emitted when a {defaultAdminDelay} change is started, setting `newDelay` as the next
     * delay to be applied between default admin transfer after `effectSchedule` has passed.
     */
    event DefaultAdminDelayChangeScheduled(uint48 newDelay, uint48 effectSchedule);

    /**
     * @dev Emitted when a {pendingDefaultAdminDelay} is reset if its schedule didn't pass.
     */
    event DefaultAdminDelayChangeCanceled();

    /**
     * @dev Returns the address of the current `DEFAULT_ADMIN_ROLE` holder.
     */
    function defaultAdmin() external view returns (address);

    /**
     * @dev Returns a tuple of a `newAdmin` and an accept schedule.
     *
     * After the `schedule` passes, the `newAdmin` will be able to accept the {defaultAdmin} role
     * by calling {acceptDefaultAdminTransfer}, completing the role transfer.
     *
     * A zero value only in `acceptSchedule` indicates no pending admin transfer.
     *
     * NOTE: A zero address `newAdmin` means that {defaultAdmin} is being renounced.
     */
    function pendingDefaultAdmin() external view returns (address newAdmin, uint48 acceptSchedule);

    /**
     * @dev Returns the delay required to schedule the acceptance of a {defaultAdmin} transfer started.
     *
     * This delay will be added to the current timestamp when calling {beginDefaultAdminTransfer} to set
     * the acceptance schedule.
     *
     * NOTE: If a delay change has been scheduled, it will take effect as soon as the schedule passes, making this
     * function returns the new delay. See {changeDefaultAdminDelay}.
     */
    function defaultAdminDelay() external view returns (uint48);

    /**
     * @dev Returns a tuple of `newDelay` and an effect schedule.
     *
     * After the `schedule` passes, the `newDelay` will get into effect immediately for every
     * new {defaultAdmin} transfer started with {beginDefaultAdminTransfer}.
     *
     * A zero value only in `effectSchedule` indicates no pending delay change.
     *
     * NOTE: A zero value only for `newDelay` means that the next {defaultAdminDelay}
     * will be zero after the effect schedule.
     */
    function pendingDefaultAdminDelay() external view returns (uint48 newDelay, uint48 effectSchedule);

    /**
     * @dev Starts a {defaultAdmin} transfer by setting a {pendingDefaultAdmin} scheduled for acceptance
     * after the current timestamp plus a {defaultAdminDelay}.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * Emits a DefaultAdminRoleChangeStarted event.
     */
    function beginDefaultAdminTransfer(address newAdmin) external;

    /**
     * @dev Cancels a {defaultAdmin} transfer previously started with {beginDefaultAdminTransfer}.
     *
     * A {pendingDefaultAdmin} not yet accepted can also be cancelled with this function.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * May emit a DefaultAdminTransferCanceled event.
     */
    function cancelDefaultAdminTransfer() external;

    /**
     * @dev Completes a {defaultAdmin} transfer previously started with {beginDefaultAdminTransfer}.
     *
     * After calling the function:
     *
     * - `DEFAULT_ADMIN_ROLE` should be granted to the caller.
     * - `DEFAULT_ADMIN_ROLE` should be revoked from the previous holder.
     * - {pendingDefaultAdmin} should be reset to zero values.
     *
     * Requirements:
     *
     * - Only can be called by the {pendingDefaultAdmin}'s `newAdmin`.
     * - The {pendingDefaultAdmin}'s `acceptSchedule` should've passed.
     */
    function acceptDefaultAdminTransfer() external;

    /**
     * @dev Initiates a {defaultAdminDelay} update by setting a {pendingDefaultAdminDelay} scheduled for getting
     * into effect after the current timestamp plus a {defaultAdminDelay}.
     *
     * This function guarantees that any call to {beginDefaultAdminTransfer} done between the timestamp this
     * method is called and the {pendingDefaultAdminDelay} effect schedule will use the current {defaultAdminDelay}
     * set before calling.
     *
     * The {pendingDefaultAdminDelay}'s effect schedule is defined in a way that waiting until the schedule and then
     * calling {beginDefaultAdminTransfer} with the new delay will take at least the same as another {defaultAdmin}
     * complete transfer (including acceptance).
     *
     * The schedule is designed for two scenarios:
     *
     * - When the delay is changed for a larger one the schedule is `block.timestamp + newDelay` capped by
     * {defaultAdminDelayIncreaseWait}.
     * - When the delay is changed for a shorter one, the schedule is `block.timestamp + (current delay - new delay)`.
     *
     * A {pendingDefaultAdminDelay} that never got into effect will be canceled in favor of a new scheduled change.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * Emits a DefaultAdminDelayChangeScheduled event and may emit a DefaultAdminDelayChangeCanceled event.
     */
    function changeDefaultAdminDelay(uint48 newDelay) external;

    /**
     * @dev Cancels a scheduled {defaultAdminDelay} change.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * May emit a DefaultAdminDelayChangeCanceled event.
     */
    function rollbackDefaultAdminDelay() external;

    /**
     * @dev Maximum time in seconds for an increase to {defaultAdminDelay} (that is scheduled using {changeDefaultAdminDelay})
     * to take effect. Default to 5 days.
     *
     * When the {defaultAdminDelay} is scheduled to be increased, it goes into effect after the new delay has passed with
     * the purpose of giving enough time for reverting any accidental change (i.e. using milliseconds instead of seconds)
     * that may lock the contract. However, to avoid excessive schedules, the wait is capped by this function and it can
     * be overrode for a custom {defaultAdminDelay} increase scheduling.
     *
     * IMPORTANT: Make sure to add a reasonable amount of time while overriding this value, otherwise,
     * there's a risk of setting a high new delay that goes into effect almost immediately without the
     * possibility of human intervention in the case of an input error (eg. set milliseconds instead of seconds).
     */
    function defaultAdminDelayIncreaseWait() external view returns (uint48);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SafeCast.sol)
// This file was procedurally generated from scripts/generate/templates/SafeCast.js.

pragma solidity ^0.8.0;

/**
 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
 * checks.
 *
 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
 * easily result in undesired exploitation or bugs, since developers usually
 * assume that overflows raise errors. `SafeCast` restores this intuition by
 * reverting the transaction when such an operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 *
 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
 * all math on `uint256` and `int256` and then downcasting.
 */
library SafeCast {
    /**
     * @dev Returns the downcasted uint248 from uint256, reverting on
     * overflow (when the input is greater than largest uint248).
     *
     * Counterpart to Solidity's `uint248` operator.
     *
     * Requirements:
     *
     * - input must fit into 248 bits
     *
     * _Available since v4.7._
     */
    function toUint248(uint256 value) internal pure returns (uint248) {
        require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits");
        return uint248(value);
    }

    /**
     * @dev Returns the downcasted uint240 from uint256, reverting on
     * overflow (when the input is greater than largest uint240).
     *
     * Counterpart to Solidity's `uint240` operator.
     *
     * Requirements:
     *
     * - input must fit into 240 bits
     *
     * _Available since v4.7._
     */
    function toUint240(uint256 value) internal pure returns (uint240) {
        require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits");
        return uint240(value);
    }

    /**
     * @dev Returns the downcasted uint232 from uint256, reverting on
     * overflow (when the input is greater than largest uint232).
     *
     * Counterpart to Solidity's `uint232` operator.
     *
     * Requirements:
     *
     * - input must fit into 232 bits
     *
     * _Available since v4.7._
     */
    function toUint232(uint256 value) internal pure returns (uint232) {
        require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits");
        return uint232(value);
    }

    /**
     * @dev Returns the downcasted uint224 from uint256, reverting on
     * overflow (when the input is greater than largest uint224).
     *
     * Counterpart to Solidity's `uint224` operator.
     *
     * Requirements:
     *
     * - input must fit into 224 bits
     *
     * _Available since v4.2._
     */
    function toUint224(uint256 value) internal pure returns (uint224) {
        require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
        return uint224(value);
    }

    /**
     * @dev Returns the downcasted uint216 from uint256, reverting on
     * overflow (when the input is greater than largest uint216).
     *
     * Counterpart to Solidity's `uint216` operator.
     *
     * Requirements:
     *
     * - input must fit into 216 bits
     *
     * _Available since v4.7._
     */
    function toUint216(uint256 value) internal pure returns (uint216) {
        require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits");
        return uint216(value);
    }

    /**
     * @dev Returns the downcasted uint208 from uint256, reverting on
     * overflow (when the input is greater than largest uint208).
     *
     * Counterpart to Solidity's `uint208` operator.
     *
     * Requirements:
     *
     * - input must fit into 208 bits
     *
     * _Available since v4.7._
     */
    function toUint208(uint256 value) internal pure returns (uint208) {
        require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits");
        return uint208(value);
    }

    /**
     * @dev Returns the downcasted uint200 from uint256, reverting on
     * overflow (when the input is greater than largest uint200).
     *
     * Counterpart to Solidity's `uint200` operator.
     *
     * Requirements:
     *
     * - input must fit into 200 bits
     *
     * _Available since v4.7._
     */
    function toUint200(uint256 value) internal pure returns (uint200) {
        require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits");
        return uint200(value);
    }

    /**
     * @dev Returns the downcasted uint192 from uint256, reverting on
     * overflow (when the input is greater than largest uint192).
     *
     * Counterpart to Solidity's `uint192` operator.
     *
     * Requirements:
     *
     * - input must fit into 192 bits
     *
     * _Available since v4.7._
     */
    function toUint192(uint256 value) internal pure returns (uint192) {
        require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits");
        return uint192(value);
    }

    /**
     * @dev Returns the downcasted uint184 from uint256, reverting on
     * overflow (when the input is greater than largest uint184).
     *
     * Counterpart to Solidity's `uint184` operator.
     *
     * Requirements:
     *
     * - input must fit into 184 bits
     *
     * _Available since v4.7._
     */
    function toUint184(uint256 value) internal pure returns (uint184) {
        require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits");
        return uint184(value);
    }

    /**
     * @dev Returns the downcasted uint176 from uint256, reverting on
     * overflow (when the input is greater than largest uint176).
     *
     * Counterpart to Solidity's `uint176` operator.
     *
     * Requirements:
     *
     * - input must fit into 176 bits
     *
     * _Available since v4.7._
     */
    function toUint176(uint256 value) internal pure returns (uint176) {
        require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits");
        return uint176(value);
    }

    /**
     * @dev Returns the downcasted uint168 from uint256, reverting on
     * overflow (when the input is greater than largest uint168).
     *
     * Counterpart to Solidity's `uint168` operator.
     *
     * Requirements:
     *
     * - input must fit into 168 bits
     *
     * _Available since v4.7._
     */
    function toUint168(uint256 value) internal pure returns (uint168) {
        require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits");
        return uint168(value);
    }

    /**
     * @dev Returns the downcasted uint160 from uint256, reverting on
     * overflow (when the input is greater than largest uint160).
     *
     * Counterpart to Solidity's `uint160` operator.
     *
     * Requirements:
     *
     * - input must fit into 160 bits
     *
     * _Available since v4.7._
     */
    function toUint160(uint256 value) internal pure returns (uint160) {
        require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits");
        return uint160(value);
    }

    /**
     * @dev Returns the downcasted uint152 from uint256, reverting on
     * overflow (when the input is greater than largest uint152).
     *
     * Counterpart to Solidity's `uint152` operator.
     *
     * Requirements:
     *
     * - input must fit into 152 bits
     *
     * _Available since v4.7._
     */
    function toUint152(uint256 value) internal pure returns (uint152) {
        require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits");
        return uint152(value);
    }

    /**
     * @dev Returns the downcasted uint144 from uint256, reverting on
     * overflow (when the input is greater than largest uint144).
     *
     * Counterpart to Solidity's `uint144` operator.
     *
     * Requirements:
     *
     * - input must fit into 144 bits
     *
     * _Available since v4.7._
     */
    function toUint144(uint256 value) internal pure returns (uint144) {
        require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits");
        return uint144(value);
    }

    /**
     * @dev Returns the downcasted uint136 from uint256, reverting on
     * overflow (when the input is greater than largest uint136).
     *
     * Counterpart to Solidity's `uint136` operator.
     *
     * Requirements:
     *
     * - input must fit into 136 bits
     *
     * _Available since v4.7._
     */
    function toUint136(uint256 value) internal pure returns (uint136) {
        require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits");
        return uint136(value);
    }

    /**
     * @dev Returns the downcasted uint128 from uint256, reverting on
     * overflow (when the input is greater than largest uint128).
     *
     * Counterpart to Solidity's `uint128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v2.5._
     */
    function toUint128(uint256 value) internal pure returns (uint128) {
        require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
        return uint128(value);
    }

    /**
     * @dev Returns the downcasted uint120 from uint256, reverting on
     * overflow (when the input is greater than largest uint120).
     *
     * Counterpart to Solidity's `uint120` operator.
     *
     * Requirements:
     *
     * - input must fit into 120 bits
     *
     * _Available since v4.7._
     */
    function toUint120(uint256 value) internal pure returns (uint120) {
        require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits");
        return uint120(value);
    }

    /**
     * @dev Returns the downcasted uint112 from uint256, reverting on
     * overflow (when the input is greater than largest uint112).
     *
     * Counterpart to Solidity's `uint112` operator.
     *
     * Requirements:
     *
     * - input must fit into 112 bits
     *
     * _Available since v4.7._
     */
    function toUint112(uint256 value) internal pure returns (uint112) {
        require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits");
        return uint112(value);
    }

    /**
     * @dev Returns the downcasted uint104 from uint256, reverting on
     * overflow (when the input is greater than largest uint104).
     *
     * Counterpart to Solidity's `uint104` operator.
     *
     * Requirements:
     *
     * - input must fit into 104 bits
     *
     * _Available since v4.7._
     */
    function toUint104(uint256 value) internal pure returns (uint104) {
        require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits");
        return uint104(value);
    }

    /**
     * @dev Returns the downcasted uint96 from uint256, reverting on
     * overflow (when the input is greater than largest uint96).
     *
     * Counterpart to Solidity's `uint96` operator.
     *
     * Requirements:
     *
     * - input must fit into 96 bits
     *
     * _Available since v4.2._
     */
    function toUint96(uint256 value) internal pure returns (uint96) {
        require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
        return uint96(value);
    }

    /**
     * @dev Returns the downcasted uint88 from uint256, reverting on
     * overflow (when the input is greater than largest uint88).
     *
     * Counterpart to Solidity's `uint88` operator.
     *
     * Requirements:
     *
     * - input must fit into 88 bits
     *
     * _Available since v4.7._
     */
    function toUint88(uint256 value) internal pure returns (uint88) {
        require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits");
        return uint88(value);
    }

    /**
     * @dev Returns the downcasted uint80 from uint256, reverting on
     * overflow (when the input is greater than largest uint80).
     *
     * Counterpart to Solidity's `uint80` operator.
     *
     * Requirements:
     *
     * - input must fit into 80 bits
     *
     * _Available since v4.7._
     */
    function toUint80(uint256 value) internal pure returns (uint80) {
        require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits");
        return uint80(value);
    }

    /**
     * @dev Returns the downcasted uint72 from uint256, reverting on
     * overflow (when the input is greater than largest uint72).
     *
     * Counterpart to Solidity's `uint72` operator.
     *
     * Requirements:
     *
     * - input must fit into 72 bits
     *
     * _Available since v4.7._
     */
    function toUint72(uint256 value) internal pure returns (uint72) {
        require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits");
        return uint72(value);
    }

    /**
     * @dev Returns the downcasted uint64 from uint256, reverting on
     * overflow (when the input is greater than largest uint64).
     *
     * Counterpart to Solidity's `uint64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v2.5._
     */
    function toUint64(uint256 value) internal pure returns (uint64) {
        require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
        return uint64(value);
    }

    /**
     * @dev Returns the downcasted uint56 from uint256, reverting on
     * overflow (when the input is greater than largest uint56).
     *
     * Counterpart to Solidity's `uint56` operator.
     *
     * Requirements:
     *
     * - input must fit into 56 bits
     *
     * _Available since v4.7._
     */
    function toUint56(uint256 value) internal pure returns (uint56) {
        require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits");
        return uint56(value);
    }

    /**
     * @dev Returns the downcasted uint48 from uint256, reverting on
     * overflow (when the input is greater than largest uint48).
     *
     * Counterpart to Solidity's `uint48` operator.
     *
     * Requirements:
     *
     * - input must fit into 48 bits
     *
     * _Available since v4.7._
     */
    function toUint48(uint256 value) internal pure returns (uint48) {
        require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits");
        return uint48(value);
    }

    /**
     * @dev Returns the downcasted uint40 from uint256, reverting on
     * overflow (when the input is greater than largest uint40).
     *
     * Counterpart to Solidity's `uint40` operator.
     *
     * Requirements:
     *
     * - input must fit into 40 bits
     *
     * _Available since v4.7._
     */
    function toUint40(uint256 value) internal pure returns (uint40) {
        require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits");
        return uint40(value);
    }

    /**
     * @dev Returns the downcasted uint32 from uint256, reverting on
     * overflow (when the input is greater than largest uint32).
     *
     * Counterpart to Solidity's `uint32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v2.5._
     */
    function toUint32(uint256 value) internal pure returns (uint32) {
        require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
        return uint32(value);
    }

    /**
     * @dev Returns the downcasted uint24 from uint256, reverting on
     * overflow (when the input is greater than largest uint24).
     *
     * Counterpart to Solidity's `uint24` operator.
     *
     * Requirements:
     *
     * - input must fit into 24 bits
     *
     * _Available since v4.7._
     */
    function toUint24(uint256 value) internal pure returns (uint24) {
        require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits");
        return uint24(value);
    }

    /**
     * @dev Returns the downcasted uint16 from uint256, reverting on
     * overflow (when the input is greater than largest uint16).
     *
     * Counterpart to Solidity's `uint16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v2.5._
     */
    function toUint16(uint256 value) internal pure returns (uint16) {
        require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
        return uint16(value);
    }

    /**
     * @dev Returns the downcasted uint8 from uint256, reverting on
     * overflow (when the input is greater than largest uint8).
     *
     * Counterpart to Solidity's `uint8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits
     *
     * _Available since v2.5._
     */
    function toUint8(uint256 value) internal pure returns (uint8) {
        require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
        return uint8(value);
    }

    /**
     * @dev Converts a signed int256 into an unsigned uint256.
     *
     * Requirements:
     *
     * - input must be greater than or equal to 0.
     *
     * _Available since v3.0._
     */
    function toUint256(int256 value) internal pure returns (uint256) {
        require(value >= 0, "SafeCast: value must be positive");
        return uint256(value);
    }

    /**
     * @dev Returns the downcasted int248 from int256, reverting on
     * overflow (when the input is less than smallest int248 or
     * greater than largest int248).
     *
     * Counterpart to Solidity's `int248` operator.
     *
     * Requirements:
     *
     * - input must fit into 248 bits
     *
     * _Available since v4.7._
     */
    function toInt248(int256 value) internal pure returns (int248 downcasted) {
        downcasted = int248(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 248 bits");
    }

    /**
     * @dev Returns the downcasted int240 from int256, reverting on
     * overflow (when the input is less than smallest int240 or
     * greater than largest int240).
     *
     * Counterpart to Solidity's `int240` operator.
     *
     * Requirements:
     *
     * - input must fit into 240 bits
     *
     * _Available since v4.7._
     */
    function toInt240(int256 value) internal pure returns (int240 downcasted) {
        downcasted = int240(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 240 bits");
    }

    /**
     * @dev Returns the downcasted int232 from int256, reverting on
     * overflow (when the input is less than smallest int232 or
     * greater than largest int232).
     *
     * Counterpart to Solidity's `int232` operator.
     *
     * Requirements:
     *
     * - input must fit into 232 bits
     *
     * _Available since v4.7._
     */
    function toInt232(int256 value) internal pure returns (int232 downcasted) {
        downcasted = int232(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 232 bits");
    }

    /**
     * @dev Returns the downcasted int224 from int256, reverting on
     * overflow (when the input is less than smallest int224 or
     * greater than largest int224).
     *
     * Counterpart to Solidity's `int224` operator.
     *
     * Requirements:
     *
     * - input must fit into 224 bits
     *
     * _Available since v4.7._
     */
    function toInt224(int256 value) internal pure returns (int224 downcasted) {
        downcasted = int224(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 224 bits");
    }

    /**
     * @dev Returns the downcasted int216 from int256, reverting on
     * overflow (when the input is less than smallest int216 or
     * greater than largest int216).
     *
     * Counterpart to Solidity's `int216` operator.
     *
     * Requirements:
     *
     * - input must fit into 216 bits
     *
     * _Available since v4.7._
     */
    function toInt216(int256 value) internal pure returns (int216 downcasted) {
        downcasted = int216(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 216 bits");
    }

    /**
     * @dev Returns the downcasted int208 from int256, reverting on
     * overflow (when the input is less than smallest int208 or
     * greater than largest int208).
     *
     * Counterpart to Solidity's `int208` operator.
     *
     * Requirements:
     *
     * - input must fit into 208 bits
     *
     * _Available since v4.7._
     */
    function toInt208(int256 value) internal pure returns (int208 downcasted) {
        downcasted = int208(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 208 bits");
    }

    /**
     * @dev Returns the downcasted int200 from int256, reverting on
     * overflow (when the input is less than smallest int200 or
     * greater than largest int200).
     *
     * Counterpart to Solidity's `int200` operator.
     *
     * Requirements:
     *
     * - input must fit into 200 bits
     *
     * _Available since v4.7._
     */
    function toInt200(int256 value) internal pure returns (int200 downcasted) {
        downcasted = int200(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 200 bits");
    }

    /**
     * @dev Returns the downcasted int192 from int256, reverting on
     * overflow (when the input is less than smallest int192 or
     * greater than largest int192).
     *
     * Counterpart to Solidity's `int192` operator.
     *
     * Requirements:
     *
     * - input must fit into 192 bits
     *
     * _Available since v4.7._
     */
    function toInt192(int256 value) internal pure returns (int192 downcasted) {
        downcasted = int192(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 192 bits");
    }

    /**
     * @dev Returns the downcasted int184 from int256, reverting on
     * overflow (when the input is less than smallest int184 or
     * greater than largest int184).
     *
     * Counterpart to Solidity's `int184` operator.
     *
     * Requirements:
     *
     * - input must fit into 184 bits
     *
     * _Available since v4.7._
     */
    function toInt184(int256 value) internal pure returns (int184 downcasted) {
        downcasted = int184(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 184 bits");
    }

    /**
     * @dev Returns the downcasted int176 from int256, reverting on
     * overflow (when the input is less than smallest int176 or
     * greater than largest int176).
     *
     * Counterpart to Solidity's `int176` operator.
     *
     * Requirements:
     *
     * - input must fit into 176 bits
     *
     * _Available since v4.7._
     */
    function toInt176(int256 value) internal pure returns (int176 downcasted) {
        downcasted = int176(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 176 bits");
    }

    /**
     * @dev Returns the downcasted int168 from int256, reverting on
     * overflow (when the input is less than smallest int168 or
     * greater than largest int168).
     *
     * Counterpart to Solidity's `int168` operator.
     *
     * Requirements:
     *
     * - input must fit into 168 bits
     *
     * _Available since v4.7._
     */
    function toInt168(int256 value) internal pure returns (int168 downcasted) {
        downcasted = int168(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 168 bits");
    }

    /**
     * @dev Returns the downcasted int160 from int256, reverting on
     * overflow (when the input is less than smallest int160 or
     * greater than largest int160).
     *
     * Counterpart to Solidity's `int160` operator.
     *
     * Requirements:
     *
     * - input must fit into 160 bits
     *
     * _Available since v4.7._
     */
    function toInt160(int256 value) internal pure returns (int160 downcasted) {
        downcasted = int160(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 160 bits");
    }

    /**
     * @dev Returns the downcasted int152 from int256, reverting on
     * overflow (when the input is less than smallest int152 or
     * greater than largest int152).
     *
     * Counterpart to Solidity's `int152` operator.
     *
     * Requirements:
     *
     * - input must fit into 152 bits
     *
     * _Available since v4.7._
     */
    function toInt152(int256 value) internal pure returns (int152 downcasted) {
        downcasted = int152(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 152 bits");
    }

    /**
     * @dev Returns the downcasted int144 from int256, reverting on
     * overflow (when the input is less than smallest int144 or
     * greater than largest int144).
     *
     * Counterpart to Solidity's `int144` operator.
     *
     * Requirements:
     *
     * - input must fit into 144 bits
     *
     * _Available since v4.7._
     */
    function toInt144(int256 value) internal pure returns (int144 downcasted) {
        downcasted = int144(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 144 bits");
    }

    /**
     * @dev Returns the downcasted int136 from int256, reverting on
     * overflow (when the input is less than smallest int136 or
     * greater than largest int136).
     *
     * Counterpart to Solidity's `int136` operator.
     *
     * Requirements:
     *
     * - input must fit into 136 bits
     *
     * _Available since v4.7._
     */
    function toInt136(int256 value) internal pure returns (int136 downcasted) {
        downcasted = int136(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 136 bits");
    }

    /**
     * @dev Returns the downcasted int128 from int256, reverting on
     * overflow (when the input is less than smallest int128 or
     * greater than largest int128).
     *
     * Counterpart to Solidity's `int128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v3.1._
     */
    function toInt128(int256 value) internal pure returns (int128 downcasted) {
        downcasted = int128(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 128 bits");
    }

    /**
     * @dev Returns the downcasted int120 from int256, reverting on
     * overflow (when the input is less than smallest int120 or
     * greater than largest int120).
     *
     * Counterpart to Solidity's `int120` operator.
     *
     * Requirements:
     *
     * - input must fit into 120 bits
     *
     * _Available since v4.7._
     */
    function toInt120(int256 value) internal pure returns (int120 downcasted) {
        downcasted = int120(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 120 bits");
    }

    /**
     * @dev Returns the downcasted int112 from int256, reverting on
     * overflow (when the input is less than smallest int112 or
     * greater than largest int112).
     *
     * Counterpart to Solidity's `int112` operator.
     *
     * Requirements:
     *
     * - input must fit into 112 bits
     *
     * _Available since v4.7._
     */
    function toInt112(int256 value) internal pure returns (int112 downcasted) {
        downcasted = int112(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 112 bits");
    }

    /**
     * @dev Returns the downcasted int104 from int256, reverting on
     * overflow (when the input is less than smallest int104 or
     * greater than largest int104).
     *
     * Counterpart to Solidity's `int104` operator.
     *
     * Requirements:
     *
     * - input must fit into 104 bits
     *
     * _Available since v4.7._
     */
    function toInt104(int256 value) internal pure returns (int104 downcasted) {
        downcasted = int104(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 104 bits");
    }

    /**
     * @dev Returns the downcasted int96 from int256, reverting on
     * overflow (when the input is less than smallest int96 or
     * greater than largest int96).
     *
     * Counterpart to Solidity's `int96` operator.
     *
     * Requirements:
     *
     * - input must fit into 96 bits
     *
     * _Available since v4.7._
     */
    function toInt96(int256 value) internal pure returns (int96 downcasted) {
        downcasted = int96(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 96 bits");
    }

    /**
     * @dev Returns the downcasted int88 from int256, reverting on
     * overflow (when the input is less than smallest int88 or
     * greater than largest int88).
     *
     * Counterpart to Solidity's `int88` operator.
     *
     * Requirements:
     *
     * - input must fit into 88 bits
     *
     * _Available since v4.7._
     */
    function toInt88(int256 value) internal pure returns (int88 downcasted) {
        downcasted = int88(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 88 bits");
    }

    /**
     * @dev Returns the downcasted int80 from int256, reverting on
     * overflow (when the input is less than smallest int80 or
     * greater than largest int80).
     *
     * Counterpart to Solidity's `int80` operator.
     *
     * Requirements:
     *
     * - input must fit into 80 bits
     *
     * _Available since v4.7._
     */
    function toInt80(int256 value) internal pure returns (int80 downcasted) {
        downcasted = int80(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 80 bits");
    }

    /**
     * @dev Returns the downcasted int72 from int256, reverting on
     * overflow (when the input is less than smallest int72 or
     * greater than largest int72).
     *
     * Counterpart to Solidity's `int72` operator.
     *
     * Requirements:
     *
     * - input must fit into 72 bits
     *
     * _Available since v4.7._
     */
    function toInt72(int256 value) internal pure returns (int72 downcasted) {
        downcasted = int72(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 72 bits");
    }

    /**
     * @dev Returns the downcasted int64 from int256, reverting on
     * overflow (when the input is less than smallest int64 or
     * greater than largest int64).
     *
     * Counterpart to Solidity's `int64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v3.1._
     */
    function toInt64(int256 value) internal pure returns (int64 downcasted) {
        downcasted = int64(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 64 bits");
    }

    /**
     * @dev Returns the downcasted int56 from int256, reverting on
     * overflow (when the input is less than smallest int56 or
     * greater than largest int56).
     *
     * Counterpart to Solidity's `int56` operator.
     *
     * Requirements:
     *
     * - input must fit into 56 bits
     *
     * _Available since v4.7._
     */
    function toInt56(int256 value) internal pure returns (int56 downcasted) {
        downcasted = int56(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 56 bits");
    }

    /**
     * @dev Returns the downcasted int48 from int256, reverting on
     * overflow (when the input is less than smallest int48 or
     * greater than largest int48).
     *
     * Counterpart to Solidity's `int48` operator.
     *
     * Requirements:
     *
     * - input must fit into 48 bits
     *
     * _Available since v4.7._
     */
    function toInt48(int256 value) internal pure returns (int48 downcasted) {
        downcasted = int48(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 48 bits");
    }

    /**
     * @dev Returns the downcasted int40 from int256, reverting on
     * overflow (when the input is less than smallest int40 or
     * greater than largest int40).
     *
     * Counterpart to Solidity's `int40` operator.
     *
     * Requirements:
     *
     * - input must fit into 40 bits
     *
     * _Available since v4.7._
     */
    function toInt40(int256 value) internal pure returns (int40 downcasted) {
        downcasted = int40(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 40 bits");
    }

    /**
     * @dev Returns the downcasted int32 from int256, reverting on
     * overflow (when the input is less than smallest int32 or
     * greater than largest int32).
     *
     * Counterpart to Solidity's `int32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v3.1._
     */
    function toInt32(int256 value) internal pure returns (int32 downcasted) {
        downcasted = int32(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 32 bits");
    }

    /**
     * @dev Returns the downcasted int24 from int256, reverting on
     * overflow (when the input is less than smallest int24 or
     * greater than largest int24).
     *
     * Counterpart to Solidity's `int24` operator.
     *
     * Requirements:
     *
     * - input must fit into 24 bits
     *
     * _Available since v4.7._
     */
    function toInt24(int256 value) internal pure returns (int24 downcasted) {
        downcasted = int24(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 24 bits");
    }

    /**
     * @dev Returns the downcasted int16 from int256, reverting on
     * overflow (when the input is less than smallest int16 or
     * greater than largest int16).
     *
     * Counterpart to Solidity's `int16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v3.1._
     */
    function toInt16(int256 value) internal pure returns (int16 downcasted) {
        downcasted = int16(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 16 bits");
    }

    /**
     * @dev Returns the downcasted int8 from int256, reverting on
     * overflow (when the input is less than smallest int8 or
     * greater than largest int8).
     *
     * Counterpart to Solidity's `int8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits
     *
     * _Available since v3.1._
     */
    function toInt8(int256 value) internal pure returns (int8 downcasted) {
        downcasted = int8(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 8 bits");
    }

    /**
     * @dev Converts an unsigned uint256 into a signed int256.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxInt256.
     *
     * _Available since v3.0._
     */
    function toInt256(uint256 value) internal pure returns (int256) {
        // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
        require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
        return int256(value);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC5313.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface for the Light Contract Ownership Standard.
 *
 * A standardized minimal interface required to identify an account that controls a contract
 *
 * _Available since v4.9._
 */
interface IERC5313 {
    /**
     * @dev Gets the address of the owner.
     */
    function owner() external view returns (address);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
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].
     *
     * CAUTION: See Security Considerations above.
     */
    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);
}

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

pragma solidity ^0.8.1;

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

        return account.code.length > 0;
    }

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

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

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

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

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

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

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

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

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

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

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

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

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

// 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);
}

// 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());
    }
}

// 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;
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (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;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}

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

pragma solidity ^0.8.0;

import "./math/Math.sol";
import "./math/SignedMath.sol";

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

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `int256` to its ASCII `string` decimal representation.
     */
    function toString(int256 value) internal pure returns (string memory) {
        return string(abi.encodePacked(value < 0 ? "-" : "", toString(SignedMath.abs(value))));
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

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

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

    /**
     * @dev Returns true if the two strings are equal.
     */
    function equal(string memory a, string memory b) internal pure returns (bool) {
        return keccak256(bytes(a)) == keccak256(bytes(b));
    }
}

// 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;
    }
}

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

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                // The surrounding unchecked block does not change this fact.
                // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1, "Math: mulDiv overflow");

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10 ** 64) {
                value /= 10 ** 64;
                result += 64;
            }
            if (value >= 10 ** 32) {
                value /= 10 ** 32;
                result += 32;
            }
            if (value >= 10 ** 16) {
                value /= 10 ** 16;
                result += 16;
            }
            if (value >= 10 ** 8) {
                value /= 10 ** 8;
                result += 8;
            }
            if (value >= 10 ** 4) {
                value /= 10 ** 4;
                result += 4;
            }
            if (value >= 10 ** 2) {
                value /= 10 ** 2;
                result += 2;
            }
            if (value >= 10 ** 1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SignedMath.sol)

pragma solidity ^0.8.0;

/**
 * @dev Standard signed math utilities missing in the Solidity language.
 */
library SignedMath {
    /**
     * @dev Returns the largest of two signed numbers.
     */
    function max(int256 a, int256 b) internal pure returns (int256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two signed numbers.
     */
    function min(int256 a, int256 b) internal pure returns (int256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two signed numbers without overflow.
     * The result is rounded towards zero.
     */
    function average(int256 a, int256 b) internal pure returns (int256) {
        // Formula from the book "Hacker's Delight"
        int256 x = (a & b) + ((a ^ b) >> 1);
        return x + (int256(uint256(x) >> 255) & (a ^ b));
    }

    /**
     * @dev Returns the absolute unsigned value of a signed value.
     */
    function abs(int256 n) internal pure returns (uint256) {
        unchecked {
            // must be unchecked in order to support `n = type(int256).min`
            return uint256(n >= 0 ? n : -n);
        }
    }
}

// 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);
}

Contract Source Code:

// SPDX-License-Identifier: MIT
pragma solidity 0.8.23;
pragma abicoder v2;

import { AccessControlDefaultAdminRules } from "@openzeppelin/contracts/access/AccessControlDefaultAdminRules.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { ReentrancyGuard } from "@openzeppelin/contracts/security/ReentrancyGuard.sol";

import "../vesting/TokenVesting.sol";

contract FairAuctionVesting is ReentrancyGuard, AccessControlDefaultAdminRules {
    using SafeERC20 for IERC20;

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

    /// @notice The contribution and claim status of each user
    struct UserInfo {
        uint256 contribution; // amount taken into account to obtain TOKEN
        bool hasClaimed; // has already claimed its contribution
    }

    /// @notice BIO's main token contract
    IERC20 public immutable BIO_TOKEN;

    /// @notice The BIO vesting contract
    TokenVesting public immutable VBIO_TOKEN;

    /// @notice The DAO token used to participate in the swap
    IERC20 public immutable DAO_TOKEN;

    /// @notice The start time of the swap period
    uint256 public immutable START_TIME;

    /// @notice The end time of the swap period
    uint256 public immutable END_TIME;

    /// @notice The information about each swaper
    mapping(address => UserInfo) public userInfo;

    /// @notice The total amount swapped
    uint256 public totalRaised;

    /// @notice The maximum amount of BIO_TOKEN to distribute during the sale
    uint256 public immutable MAX_BIO_TO_DISTRIBUTE;

    /// @notice The maximum amount of VBIO_TOKEN to distribute during the sale
    uint256 public immutable MAX_VBIO_TO_DISTRIBUTE;

    /// @notice The minimum amount to raise to distribute the maximum amount of BIO and vBIO
    uint256 public immutable MIN_DAO_RAISED_FOR_MAX_BIO;

    /// @notice The maximum amount to raise to distribute the maximum amount of BIO and vBIO
    uint256 public immutable MAX_DAO_RAISE;

    /// @notice The treasury multisig, which will receive the swaps
    address public immutable treasury;

    /// @notice Whether unsold tokens have been withdrawn
    bool public unsoldTokensWithdrew;

    /// @notice Whether the claim period is enabled
    bool public claimEnabled;

    /// @notice Whether the sale is paused
    bool public isPaused;

    // Parameters for vestingSchedule setups on vBIO
    /// @notice The cliff period for vesting
    uint256 public vestingCliff;
    /// @notice The start time for vesting
    uint256 public vestingStart;
    /// @notice The duration of the vesting period
    uint256 public vestingDuration = 365 days;
    /// @notice The number of slices per second for vesting
    uint256 public vestingSlicePerSecond = 1;
    /// @notice Whether the vesting is revocable
    bool public vestingIsRevocable = false;

    /**
     * @notice Constructor for the FairAuctionVesting contract.
     * @param bioToken_ The address of the BIO token contract.
     * @param vbioToken_ The address of the VBIO token vesting contract.
     * @param daoToken_ The address of the DAO token contract used to swap.
     * @param startTime_ The start time of the sale.
     * @param endTime_ The end time of the sale.
     * @param treasury_ The address of the treasury multisig, which will receive the raised amount.
     * @param maxToDistribute_ The maximum amount of BIO tokens to distribute during the sale.
     * @param maxToDistribute2_ The maximum amount of VBIO tokens to distribute during the sale.
     * @param minToRaise_ The minimum amount to raise for maximum BIO token distribution.
     *
     * Reverts if the start time is later than or equal to the end time, if the treasury address is the zero address,
     * or if the BIO or VBIO token addresses are the zero address. Vesting start time is set to the end time of the swap period.
     */
    constructor(
        IERC20 bioToken_,
        TokenVesting vbioToken_,
        IERC20 daoToken_,
        uint256 startTime_,
        uint256 endTime_,
        address treasury_,
        uint256 maxToDistribute_,
        uint256 maxToDistribute2_,
        uint256 minToRaise_,
        uint256 maxToRaise_
    ) AccessControlDefaultAdminRules(0, msg.sender) {
        if (startTime_ < block.timestamp) revert InvalidConstructorParameters();
        if (startTime_ >= endTime_) revert InvalidConstructorParameters();
        if (treasury_ == address(0)) revert InvalidConstructorParameters();
        if (address(bioToken_) == address(0)) revert InvalidConstructorParameters();
        if (address(vbioToken_) == address(0)) revert InvalidConstructorParameters();
        if (address(daoToken_) == address(0)) revert InvalidConstructorParameters();

        BIO_TOKEN = bioToken_;
        VBIO_TOKEN = vbioToken_;
        DAO_TOKEN = daoToken_;
        START_TIME = startTime_;
        END_TIME = endTime_;
        vestingStart = endTime_;
        treasury = treasury_;
        MAX_BIO_TO_DISTRIBUTE = maxToDistribute_;
        MAX_VBIO_TO_DISTRIBUTE = maxToDistribute2_;
        MIN_DAO_RAISED_FOR_MAX_BIO = minToRaise_;
        if (maxToRaise_ == 0) {
            maxToRaise_ = type(uint256).max;
        }
        MAX_DAO_RAISE = maxToRaise_;
    }

    /**
     * EVENTS
     */
    event Swap(address indexed user, uint256 amount);
    event Claim(address indexed user, uint256 amount, uint256 amount2);
    event EmergencyWithdraw(address token, uint256 amount);
    event SetPause(bool status);

    /**
     * ERRORS
     */

    /// @dev This error is fired when trying to perform an action that is not
    /// supported by the contract, like transfers and approvals. These actions
    /// will never be supported.
    error InvalidConstructorParameters();
    error SaleInactive();
    error SaleNotFilled();
    error SalePause();
    error SaleNotEnded();
    error SaleNotClaimable();
    error ZeroAmount();
    error ZeroContribution();
    error AlreadyClaimed();
    error TokensAlreadyWithdrawn();
    error TransferFailed();
    error InvalidScheduleParameter();
    error SaleStarted();
    error CapReached();
    error MinRaiseReached();

    /**
     * MODIFIERS
     */

    /**
     * @dev Check whether the sale is currently active
     *
     * Will be marked as inactive if BIO_TOKEN has not been swapped into the contract
     */
    modifier isSaleActive() {
        if (!hasStarted() || hasEnded()) revert SaleInactive();
        if (BIO_TOKEN.balanceOf(address(this)) < (MAX_BIO_TO_DISTRIBUTE + MAX_VBIO_TO_DISTRIBUTE)) revert SaleNotFilled();
        // check if this contract has vesting creator role
        if (!VBIO_TOKEN.hasRole(VBIO_TOKEN.VESTING_CREATOR_ROLE(), address(this))) revert SaleNotFilled();
        if (totalRaised >= MAX_DAO_RAISE) revert CapReached();
        _;
    }

    /**
     * @dev Check whether the sale is currently paused
     */
    modifier isNotPaused() {
        if (isPaused) revert SalePause();
        _;
    }

    /**
     * @dev Check whether users can claim their purchased BIO_TOKEN
     *
     * If sale has not ended but the cap is reached and claim is enabled, users can claim their tokens
     * If sale has ended
     */
    modifier isClaimable() {
        if (!hasEnded() && totalRaised < MAX_DAO_RAISE) revert SaleNotEnded();
        if (!claimEnabled) revert SaleNotClaimable();
        _;
    }

    /**
     * PUBLIC VIEWS
     */

    /**
     * @dev Get remaining duration before the end of the sale
     */
    function getRemainingTime() external view returns (uint256) {
        if (hasEnded()) return 0;
        return END_TIME - _currentBlockTimestamp();
    }

    /**
     * @dev Returns whether the sale has already started
     */
    function hasStarted() public view returns (bool) {
        return _currentBlockTimestamp() >= START_TIME;
    }

    /**
     * @dev Returns whether the sale has already ended
     */
    function hasEnded() public view returns (bool) {
        return END_TIME <= _currentBlockTimestamp();
    }

    /**
     * @dev Returns the amount of BIO_TOKEN to be distributed based on the current total raised
     */
    function bioToDistribute() public view returns (uint256) {
        if (MIN_DAO_RAISED_FOR_MAX_BIO > totalRaised) {
            return MAX_BIO_TO_DISTRIBUTE * totalRaised / MIN_DAO_RAISED_FOR_MAX_BIO;
        }
        return MAX_BIO_TO_DISTRIBUTE;
    }

    /**
     * @dev Returns the amount of VBIO_TOKEN to be distributed based on the current total raised
     */
    function vbioToDistribute() public view returns (uint256) {
        if (MIN_DAO_RAISED_FOR_MAX_BIO > totalRaised) {
            return MAX_VBIO_TO_DISTRIBUTE * totalRaised / MIN_DAO_RAISED_FOR_MAX_BIO;
        }
        return MAX_VBIO_TO_DISTRIBUTE;
    }

    /**
     * @dev Returns the amount of BIO_TOKEN + VBIO_TOKEN to be distributed based on the current total raised
     */
    function tokensToDistribute() public view returns (uint256) {
        return bioToDistribute() + vbioToDistribute();
    }

    /**
     * @dev Get user tokens amount to claim
     */
    function getExpectedClaimAmount(address account) public view returns (uint256 bioTokenAmount, uint256 vbioTokenAmount) {
        if (totalRaised == 0) return (0, 0);

        UserInfo memory user = userInfo[account];
        bioTokenAmount = user.contribution * bioToDistribute() / totalRaised;
        vbioTokenAmount = user.contribution * vbioToDistribute() / totalRaised;
    }

    /**
     * @dev Purchase a contribution for the sale for a value of "amount" DAO_TOKEN
     */
    function swap(uint256 amount) external isSaleActive isNotPaused nonReentrant {
        if (amount == 0) revert ZeroAmount();
        
        // If the user tries to swap more than the remaining amount, 
        // we will swap the remaining amount
        if (MAX_DAO_RAISE - totalRaised < amount) {
            amount = MAX_DAO_RAISE - totalRaised;
        } 

        // Update user information and total raised
        UserInfo storage user = userInfo[msg.sender];
        user.contribution = user.contribution + amount;
        totalRaised = totalRaised + amount;

        // Emit an event for the purchase
        emit Swap(msg.sender, amount);

        // Transfer DAO_TOKEN directly from the sender to the treasury
        DAO_TOKEN.safeTransferFrom(msg.sender, treasury, amount);
    }

    /**
     * @dev Claim purchased BIO_TOKEN during the sale
     */
    function claim() external nonReentrant isClaimable {
        UserInfo storage user = userInfo[msg.sender];

        if (totalRaised == 0 || user.contribution == 0) revert ZeroContribution();
        if (user.hasClaimed) revert AlreadyClaimed();

        (uint256 bioAmount, uint256 vbioAmount) = getExpectedClaimAmount(msg.sender);

        uint256 contractBalance = BIO_TOKEN.balanceOf(address(this));
        uint256 totalRequired = bioAmount + vbioAmount;

        // Check if the contract has enough BIO_TOKEN for the claim
        if (totalRequired > contractBalance) revert TransferFailed();

        user.hasClaimed = true;

        emit Claim(msg.sender, bioAmount, vbioAmount);

        // Transfer BIO_TOKEN to the user
        if (bioAmount > 0) {
            bool bioTransferSuccess = BIO_TOKEN.transfer(msg.sender, bioAmount);
            if (!bioTransferSuccess) revert TransferFailed();
        }

        // Transfer BIO_TOKEN to the VBIO_TOKEN contract and create vesting schedule
        if (vbioAmount > 0) {
            bool vbioTransferSuccess = BIO_TOKEN.transfer(address(VBIO_TOKEN), vbioAmount);
            if (!vbioTransferSuccess) revert TransferFailed();
            VBIO_TOKEN.createVestingSchedule(
                msg.sender, vestingStart, vestingCliff, vestingDuration, vestingSlicePerSecond, vestingIsRevocable, vbioAmount
            );
        }
    }

    /**
     * OWNABLE FUNCTIONS
     */
    function setPause(bool value) external onlyRole(PAUSER_ROLE) {
        isPaused = value;
        emit SetPause(value);
    }

    /**
     * @dev Withdraw unsold BIO_TOKEN + VBIO_TOKEN if MIN_DAO_RAISED_FOR_MAX_BIO has not been reached
     *
     * Must only be called by the Admin
     */
    function withdrawUnsoldTokens() external onlyRole(DEFAULT_ADMIN_ROLE) {
        if (!hasEnded()) revert SaleNotEnded();
        if (totalRaised >= MIN_DAO_RAISED_FOR_MAX_BIO) revert MinRaiseReached();
        if (unsoldTokensWithdrew) revert TokensAlreadyWithdrawn();

        uint256 totalBIOSold = bioToDistribute();
        uint256 totalVBIOSold = vbioToDistribute();

        unsoldTokensWithdrew = true;
        //because VBIO is BIO and is sent to VBIO contract before claiming
        BIO_TOKEN.transfer(treasury, MAX_BIO_TO_DISTRIBUTE + MAX_VBIO_TO_DISTRIBUTE - totalBIOSold - totalVBIOSold);
    }

    // setters

    function setVestingStart(uint256 start_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _start should be no further away than 30 weeks
        if (start_ > block.timestamp + 30 weeks) revert InvalidScheduleParameter();
        vestingStart = start_;
    }

    function setCliff(uint256 cliff_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _duration must be longer than _cliff
        if (vestingDuration < cliff_) revert InvalidScheduleParameter();
        vestingCliff = cliff_;
    }

    function setDuration(uint256 duration_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _duration should be at least 7 days and max 50 years
        if (duration_ < 7 days || duration_ > 50 * (365 days)) revert InvalidScheduleParameter();
        vestingDuration = duration_;
    }

    function setSlicePerSecond(uint256 slicePerSecond_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        // _slicePeriodSeconds should be between 1 and 60 seconds
        if (slicePerSecond_ == 0 || slicePerSecond_ > 60) revert InvalidScheduleParameter();
        vestingSlicePerSecond = slicePerSecond_;
    }

    function setIsRevocable(bool isRevocable_) external onlyRole(DEFAULT_ADMIN_ROLE) {
        // cannot update vesting parameter after the sale has started
        if (hasStarted()) revert SaleStarted();
        vestingIsRevocable = isRevocable_;
    }

    /**
     * /!\ EMERGENCY ONLY
     */

    /**
     * @dev Failsafe
     */
    function emergencyWithdrawFunds(address token, uint256 amount) external onlyRole(DEFAULT_ADMIN_ROLE) {
        IERC20(token).safeTransfer(treasury, amount);

        emit EmergencyWithdraw(token, amount);
    }

    /**
     * @dev Failsafe
     */
    function emergencyWithdrawBIO() external onlyRole(DEFAULT_ADMIN_ROLE) {
        uint256 amount = BIO_TOKEN.balanceOf(address(this));
        BIO_TOKEN.safeTransfer(treasury, amount);

        emit EmergencyWithdraw(address(BIO_TOKEN), amount);
    }

    function enableClaim() external onlyRole(DEFAULT_ADMIN_ROLE) {
        claimEnabled = true;
    }

    /**
     * INTERNAL FUNCTIONS
     */

    /**
     * @dev Utility function to get the current block timestamp
     */
    function _currentBlockTimestamp() internal view virtual returns (uint256) {
        return block.timestamp;
    }
}

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

pragma solidity ^0.8.0;

import "./AccessControl.sol";
import "./IAccessControlDefaultAdminRules.sol";
import "../utils/math/SafeCast.sol";
import "../interfaces/IERC5313.sol";

/**
 * @dev Extension of {AccessControl} that allows specifying special rules to manage
 * the `DEFAULT_ADMIN_ROLE` holder, which is a sensitive role with special permissions
 * over other roles that may potentially have privileged rights in the system.
 *
 * If a specific role doesn't have an admin role assigned, the holder of the
 * `DEFAULT_ADMIN_ROLE` will have the ability to grant it and revoke it.
 *
 * This contract implements the following risk mitigations on top of {AccessControl}:
 *
 * * Only one account holds the `DEFAULT_ADMIN_ROLE` since deployment until it's potentially renounced.
 * * Enforces a 2-step process to transfer the `DEFAULT_ADMIN_ROLE` to another account.
 * * Enforces a configurable delay between the two steps, with the ability to cancel before the transfer is accepted.
 * * The delay can be changed by scheduling, see {changeDefaultAdminDelay}.
 * * It is not possible to use another role to manage the `DEFAULT_ADMIN_ROLE`.
 *
 * Example usage:
 *
 * ```solidity
 * contract MyToken is AccessControlDefaultAdminRules {
 *   constructor() AccessControlDefaultAdminRules(
 *     3 days,
 *     msg.sender // Explicit initial `DEFAULT_ADMIN_ROLE` holder
 *    ) {}
 * }
 * ```
 *
 * _Available since v4.9._
 */
abstract contract AccessControlDefaultAdminRules is IAccessControlDefaultAdminRules, IERC5313, AccessControl {
    // pending admin pair read/written together frequently
    address private _pendingDefaultAdmin;
    uint48 private _pendingDefaultAdminSchedule; // 0 == unset

    uint48 private _currentDelay;
    address private _currentDefaultAdmin;

    // pending delay pair read/written together frequently
    uint48 private _pendingDelay;
    uint48 private _pendingDelaySchedule; // 0 == unset

    /**
     * @dev Sets the initial values for {defaultAdminDelay} and {defaultAdmin} address.
     */
    constructor(uint48 initialDelay, address initialDefaultAdmin) {
        require(initialDefaultAdmin != address(0), "AccessControl: 0 default admin");
        _currentDelay = initialDelay;
        _grantRole(DEFAULT_ADMIN_ROLE, initialDefaultAdmin);
    }

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

    /**
     * @dev See {IERC5313-owner}.
     */
    function owner() public view virtual returns (address) {
        return defaultAdmin();
    }

    ///
    /// Override AccessControl role management
    ///

    /**
     * @dev See {AccessControl-grantRole}. Reverts for `DEFAULT_ADMIN_ROLE`.
     */
    function grantRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        require(role != DEFAULT_ADMIN_ROLE, "AccessControl: can't directly grant default admin role");
        super.grantRole(role, account);
    }

    /**
     * @dev See {AccessControl-revokeRole}. Reverts for `DEFAULT_ADMIN_ROLE`.
     */
    function revokeRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        require(role != DEFAULT_ADMIN_ROLE, "AccessControl: can't directly revoke default admin role");
        super.revokeRole(role, account);
    }

    /**
     * @dev See {AccessControl-renounceRole}.
     *
     * For the `DEFAULT_ADMIN_ROLE`, it only allows renouncing in two steps by first calling
     * {beginDefaultAdminTransfer} to the `address(0)`, so it's required that the {pendingDefaultAdmin} schedule
     * has also passed when calling this function.
     *
     * After its execution, it will not be possible to call `onlyRole(DEFAULT_ADMIN_ROLE)` functions.
     *
     * NOTE: Renouncing `DEFAULT_ADMIN_ROLE` will leave the contract without a {defaultAdmin},
     * thereby disabling any functionality that is only available for it, and the possibility of reassigning a
     * non-administrated role.
     */
    function renounceRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        if (role == DEFAULT_ADMIN_ROLE && account == defaultAdmin()) {
            (address newDefaultAdmin, uint48 schedule) = pendingDefaultAdmin();
            require(
                newDefaultAdmin == address(0) && _isScheduleSet(schedule) && _hasSchedulePassed(schedule),
                "AccessControl: only can renounce in two delayed steps"
            );
            delete _pendingDefaultAdminSchedule;
        }
        super.renounceRole(role, account);
    }

    /**
     * @dev See {AccessControl-_grantRole}.
     *
     * For `DEFAULT_ADMIN_ROLE`, it only allows granting if there isn't already a {defaultAdmin} or if the
     * role has been previously renounced.
     *
     * NOTE: Exposing this function through another mechanism may make the `DEFAULT_ADMIN_ROLE`
     * assignable again. Make sure to guarantee this is the expected behavior in your implementation.
     */
    function _grantRole(bytes32 role, address account) internal virtual override {
        if (role == DEFAULT_ADMIN_ROLE) {
            require(defaultAdmin() == address(0), "AccessControl: default admin already granted");
            _currentDefaultAdmin = account;
        }
        super._grantRole(role, account);
    }

    /**
     * @dev See {AccessControl-_revokeRole}.
     */
    function _revokeRole(bytes32 role, address account) internal virtual override {
        if (role == DEFAULT_ADMIN_ROLE && account == defaultAdmin()) {
            delete _currentDefaultAdmin;
        }
        super._revokeRole(role, account);
    }

    /**
     * @dev See {AccessControl-_setRoleAdmin}. Reverts for `DEFAULT_ADMIN_ROLE`.
     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual override {
        require(role != DEFAULT_ADMIN_ROLE, "AccessControl: can't violate default admin rules");
        super._setRoleAdmin(role, adminRole);
    }

    ///
    /// AccessControlDefaultAdminRules accessors
    ///

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function defaultAdmin() public view virtual returns (address) {
        return _currentDefaultAdmin;
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function pendingDefaultAdmin() public view virtual returns (address newAdmin, uint48 schedule) {
        return (_pendingDefaultAdmin, _pendingDefaultAdminSchedule);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function defaultAdminDelay() public view virtual returns (uint48) {
        uint48 schedule = _pendingDelaySchedule;
        return (_isScheduleSet(schedule) && _hasSchedulePassed(schedule)) ? _pendingDelay : _currentDelay;
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function pendingDefaultAdminDelay() public view virtual returns (uint48 newDelay, uint48 schedule) {
        schedule = _pendingDelaySchedule;
        return (_isScheduleSet(schedule) && !_hasSchedulePassed(schedule)) ? (_pendingDelay, schedule) : (0, 0);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function defaultAdminDelayIncreaseWait() public view virtual returns (uint48) {
        return 5 days;
    }

    ///
    /// AccessControlDefaultAdminRules public and internal setters for defaultAdmin/pendingDefaultAdmin
    ///

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function beginDefaultAdminTransfer(address newAdmin) public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _beginDefaultAdminTransfer(newAdmin);
    }

    /**
     * @dev See {beginDefaultAdminTransfer}.
     *
     * Internal function without access restriction.
     */
    function _beginDefaultAdminTransfer(address newAdmin) internal virtual {
        uint48 newSchedule = SafeCast.toUint48(block.timestamp) + defaultAdminDelay();
        _setPendingDefaultAdmin(newAdmin, newSchedule);
        emit DefaultAdminTransferScheduled(newAdmin, newSchedule);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function cancelDefaultAdminTransfer() public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _cancelDefaultAdminTransfer();
    }

    /**
     * @dev See {cancelDefaultAdminTransfer}.
     *
     * Internal function without access restriction.
     */
    function _cancelDefaultAdminTransfer() internal virtual {
        _setPendingDefaultAdmin(address(0), 0);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function acceptDefaultAdminTransfer() public virtual {
        (address newDefaultAdmin, ) = pendingDefaultAdmin();
        require(_msgSender() == newDefaultAdmin, "AccessControl: pending admin must accept");
        _acceptDefaultAdminTransfer();
    }

    /**
     * @dev See {acceptDefaultAdminTransfer}.
     *
     * Internal function without access restriction.
     */
    function _acceptDefaultAdminTransfer() internal virtual {
        (address newAdmin, uint48 schedule) = pendingDefaultAdmin();
        require(_isScheduleSet(schedule) && _hasSchedulePassed(schedule), "AccessControl: transfer delay not passed");
        _revokeRole(DEFAULT_ADMIN_ROLE, defaultAdmin());
        _grantRole(DEFAULT_ADMIN_ROLE, newAdmin);
        delete _pendingDefaultAdmin;
        delete _pendingDefaultAdminSchedule;
    }

    ///
    /// AccessControlDefaultAdminRules public and internal setters for defaultAdminDelay/pendingDefaultAdminDelay
    ///

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function changeDefaultAdminDelay(uint48 newDelay) public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _changeDefaultAdminDelay(newDelay);
    }

    /**
     * @dev See {changeDefaultAdminDelay}.
     *
     * Internal function without access restriction.
     */
    function _changeDefaultAdminDelay(uint48 newDelay) internal virtual {
        uint48 newSchedule = SafeCast.toUint48(block.timestamp) + _delayChangeWait(newDelay);
        _setPendingDelay(newDelay, newSchedule);
        emit DefaultAdminDelayChangeScheduled(newDelay, newSchedule);
    }

    /**
     * @inheritdoc IAccessControlDefaultAdminRules
     */
    function rollbackDefaultAdminDelay() public virtual onlyRole(DEFAULT_ADMIN_ROLE) {
        _rollbackDefaultAdminDelay();
    }

    /**
     * @dev See {rollbackDefaultAdminDelay}.
     *
     * Internal function without access restriction.
     */
    function _rollbackDefaultAdminDelay() internal virtual {
        _setPendingDelay(0, 0);
    }

    /**
     * @dev Returns the amount of seconds to wait after the `newDelay` will
     * become the new {defaultAdminDelay}.
     *
     * The value returned guarantees that if the delay is reduced, it will go into effect
     * after a wait that honors the previously set delay.
     *
     * See {defaultAdminDelayIncreaseWait}.
     */
    function _delayChangeWait(uint48 newDelay) internal view virtual returns (uint48) {
        uint48 currentDelay = defaultAdminDelay();

        // When increasing the delay, we schedule the delay change to occur after a period of "new delay" has passed, up
        // to a maximum given by defaultAdminDelayIncreaseWait, by default 5 days. For example, if increasing from 1 day
        // to 3 days, the new delay will come into effect after 3 days. If increasing from 1 day to 10 days, the new
        // delay will come into effect after 5 days. The 5 day wait period is intended to be able to fix an error like
        // using milliseconds instead of seconds.
        //
        // When decreasing the delay, we wait the difference between "current delay" and "new delay". This guarantees
        // that an admin transfer cannot be made faster than "current delay" at the time the delay change is scheduled.
        // For example, if decreasing from 10 days to 3 days, the new delay will come into effect after 7 days.
        return
            newDelay > currentDelay
                ? uint48(Math.min(newDelay, defaultAdminDelayIncreaseWait())) // no need to safecast, both inputs are uint48
                : currentDelay - newDelay;
    }

    ///
    /// Private setters
    ///

    /**
     * @dev Setter of the tuple for pending admin and its schedule.
     *
     * May emit a DefaultAdminTransferCanceled event.
     */
    function _setPendingDefaultAdmin(address newAdmin, uint48 newSchedule) private {
        (, uint48 oldSchedule) = pendingDefaultAdmin();

        _pendingDefaultAdmin = newAdmin;
        _pendingDefaultAdminSchedule = newSchedule;

        // An `oldSchedule` from `pendingDefaultAdmin()` is only set if it hasn't been accepted.
        if (_isScheduleSet(oldSchedule)) {
            // Emit for implicit cancellations when another default admin was scheduled.
            emit DefaultAdminTransferCanceled();
        }
    }

    /**
     * @dev Setter of the tuple for pending delay and its schedule.
     *
     * May emit a DefaultAdminDelayChangeCanceled event.
     */
    function _setPendingDelay(uint48 newDelay, uint48 newSchedule) private {
        uint48 oldSchedule = _pendingDelaySchedule;

        if (_isScheduleSet(oldSchedule)) {
            if (_hasSchedulePassed(oldSchedule)) {
                // Materialize a virtual delay
                _currentDelay = _pendingDelay;
            } else {
                // Emit for implicit cancellations when another delay was scheduled.
                emit DefaultAdminDelayChangeCanceled();
            }
        }

        _pendingDelay = newDelay;
        _pendingDelaySchedule = newSchedule;
    }

    ///
    /// Private helpers
    ///

    /**
     * @dev Defines if an `schedule` is considered set. For consistency purposes.
     */
    function _isScheduleSet(uint48 schedule) private pure returns (bool) {
        return schedule != 0;
    }

    /**
     * @dev Defines if an `schedule` is considered passed. For consistency purposes.
     */
    function _hasSchedulePassed(uint48 schedule) private view returns (bool) {
        return schedule < block.timestamp;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
    }

    function _nonReentrantAfter() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
     * `nonReentrant` function in the call stack.
     */
    function _reentrancyGuardEntered() internal view returns (bool) {
        return _status == _ENTERED;
    }
}

// contracts/TokenVesting.sol
// SPDX-License-Identifier: Apache-2.0
pragma solidity 0.8.23;

import { IERC20Metadata } from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import { AccessControlDefaultAdminRules } from "@openzeppelin/contracts/access/AccessControlDefaultAdminRules.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { ReentrancyGuard } from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import { Pausable } from "@openzeppelin/contracts/security/Pausable.sol";

/// @title TokenVesting - On-Chain vesting scheme enabled by smart contracts.
/// The TokenVesting contract can release its token balance gradually like a
/// typical vesting scheme, with a cliff and vesting period. The contract owner
/// can create vesting schedules for different users, even multiple for the same person.
/// Vesting schedules are optionally revokable by the owner. Additionally the
/// smart contract functions as an ERC20 compatible non-transferable virtual
/// token which can be used e.g. for governance.
/// This work is based on the TokenVesting contract by schmackofant
/// (https://github.com/moleculeprotocol/token-vesting-contract/)
/// and was extended to support the purchasing of vesting schedules and tokens for tax reasons
/// @author ElliottAnastassios (MTX Studio) - [email protected]
/// @author clepp (MTX Studio) - [email protected]
/// @author Schmackofant - [email protected]

contract TokenVesting is IERC20Metadata, ReentrancyGuard, Pausable, AccessControlDefaultAdminRules {
    using SafeERC20 for IERC20Metadata;

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

    /// VARIABLES ///

    /**
     * @notice The ERC20 name of the virtual token
     */
    string public override name;

    /**
     * @notice The ERC20 symbol of the virtual token
     */
    string public override symbol;

    /**
     * @notice address of the ERC20 underlying Token
     */
    IERC20Metadata public immutable underlyingToken;

    /**
     * @notice The ERC20 number of decimals of the virtual token
     * @dev This contract only supports underlying Token with 18 decimals
     */
    uint8 public constant override decimals = 18;

    /**
     * @notice total amount of base tokens in all vesting schedules
     */
    uint256 internal vestingSchedulesTotalAmount;

    enum Status {
        INVALID, //0
        INITIALIZED,
        REVOKED
    }

    /// STRUCTS ///

    /**
     * @dev vesting schedule struct
     * @param cliff cliff period in seconds
     * @param start start time of the vesting period
     * @param duration duration of the vesting period in seconds
     * @param slicePeriodSeconds duration of a slice period for the vesting in seconds
     * @param amountTotal total amount of tokens to be released at the end of the vesting
     * @param released amount of tokens released so far
     * @param status schedule status (initialized, revoked)
     * @param beneficiary address of beneficiary of the vesting schedule
     * @param revokable whether or not the vesting is revokable
     */
    struct VestingSchedule {
        uint256 cliff;
        uint256 start;
        uint256 duration;
        uint256 slicePeriodSeconds;
        uint256 amountTotal;
        uint256 released;
        Status status;
        address beneficiary;
        bool revokable;
    }

    /// MAPPINGS ///

    /**
     * @dev This mapping is used to keep track of the vesting schedules
     */
    mapping(bytes32 => VestingSchedule) internal vestingSchedules;

    /**
     * @notice This mapping is used to keep track of the number of vesting schedules for each beneficiary
     */
    mapping(address => uint256) public holdersVestingScheduleCount;

    /**
     * @dev This mapping is used to keep track of the total amount of vested tokens for each beneficiary
     */
    mapping(address => uint256) internal holdersVestedAmount;

    /// EVENTS ///

    event ScheduleCreated(
        bytes32 indexed scheduleId,
        address indexed beneficiary,
        uint256 amount,
        uint256 start,
        uint256 cliff,
        uint256 duration,
        uint256 slicePeriodSeconds,
        bool revokable
    );
    event TokensReleased(bytes32 indexed scheduleId, address indexed beneficiary, uint256 amount);
    event ScheduleRevoked(bytes32 indexed scheduleId);

    /// MODIFIERS ///

    /**
     * @dev Reverts if the vesting schedule does not exist or has been revoked.
     */
    modifier onlyIfVestingScheduleNotRevoked(bytes32 vestingScheduleId) {
        // Check if schedule exists
        if (vestingSchedules[vestingScheduleId].duration == 0) revert InvalidSchedule();
        //slither-disable-next-line incorrect-equality
        if (vestingSchedules[vestingScheduleId].status == Status.REVOKED) revert ScheduleWasRevoked();
        _;
    }

    /// ERRORS ///

    /**
     * @dev This error is fired when trying to perform an action that is not
     * supported by the contract, like transfers and approvals. These actions
     * will never be supported.
     */
    error NotSupported();

    error DecimalsError();
    error InsufficientTokensInContract();
    error InsufficientReleasableTokens();
    error InvalidSchedule();
    error InvalidDuration();
    error InvalidAmount();
    error InvalidSlicePeriod();
    error InvalidStart();
    error DurationShorterThanCliff();
    error NotRevokable();
    error Unauthorized();
    error ScheduleWasRevoked();
    error TooManySchedulesForBeneficiary();
    error VestingScheduleCapacityReached();
    error InvalidAddress();

    /// CONSTRUCTOR ///

    /**
     * @notice Creates a vesting contract.
     * @param _underlyingToken address of the ERC20 base token contract
     * @param _name name of the virtual token
     * @param _symbol symbol of the virtual token
     */
    constructor(IERC20Metadata _underlyingToken, string memory _name, string memory _symbol, address _vestingCreator)
        AccessControlDefaultAdminRules(0, msg.sender)
    {
        underlyingToken = _underlyingToken;
        if (underlyingToken.decimals() != 18) revert DecimalsError();
        name = _name;
        symbol = _symbol;
        _grantRole(VESTING_CREATOR_ROLE, _vestingCreator);
    }

    /// FUNCTIONS ///

    /**
     * @dev All types of transfers are permanently disabled.
     */
    function transferFrom(address, address, uint256) public pure override returns (bool) {
        revert NotSupported();
    }

    /**
     * @dev All types of transfers are permanently disabled.
     */
    function transfer(address, uint256) public pure override returns (bool) {
        revert NotSupported();
    }

    /**
     * @dev All types of approvals are permanently disabled to reduce code size.
     */
    function approve(address, uint256) public pure override returns (bool) {
        revert NotSupported();
    }

    /**
     * @dev Approvals cannot be set, so allowances are always zero.
     */
    function allowance(address, address) public pure override returns (uint256) {
        return 0;
    }

    /**
     * @notice Returns the amount of virtual tokens in existence
     */
    function totalSupply() public view virtual override returns (uint256) {
        return vestingSchedulesTotalAmount;
    }

    /**
     * @notice Returns the sum of virtual tokens for a user
     * @param user The user for whom the balance is calculated
     * @return Balance of the user
     */
    function balanceOf(address user) public view virtual override returns (uint256) {
        return holdersVestedAmount[user];
    }

    /**
     * @notice Returns the vesting schedule information for a given holder and index.
     * @return the vesting schedule structure information
     */
    function getVestingScheduleByAddressAndIndex(address holder, uint256 index) external view returns (VestingSchedule memory) {
        return getVestingSchedule(computeVestingScheduleIdForAddressAndIndex(holder, index));
    }

    /**
     * @notice Public function for creating a vesting schedule.
     * @param _beneficiary address of the beneficiary to whom vested tokens are transferred
     * @param _start start time of the vesting period
     * @param _cliff duration in seconds of the cliff in which tokens will begin to vest
     * @param _duration duration in seconds of the period in which the tokens will vest
     * @param _slicePeriodSeconds duration of a slice period for the vesting in seconds
     * @param _revokable whether the vesting is revokable or not
     * @param _amount total amount of tokens to be released at the end of the vesting
     */
    function createVestingSchedule(
        address _beneficiary,
        uint256 _start,
        uint256 _cliff,
        uint256 _duration,
        uint256 _slicePeriodSeconds,
        bool _revokable,
        uint256 _amount
    ) external whenNotPaused onlyRole(VESTING_CREATOR_ROLE) {
        _createVestingSchedule(_beneficiary, _start, _cliff, _duration, _slicePeriodSeconds, _revokable, _amount);
    }

    /**
     * @notice Internal function for creating a vesting schedule.
     * @param _beneficiary address of the beneficiary to whom vested tokens are transferred
     * @param _start start time of the vesting period
     * @param _cliff duration in seconds of the cliff in which tokens will begin to vest
     * @param _duration duration in seconds of the period in which the tokens will vest
     * @param _slicePeriodSeconds duration of a slice period for the vesting in seconds
     * @param _revokable whether the vesting is revokable or not
     * @param _amount total amount of tokens to be released at the end of the vesting
     */
    function _createVestingSchedule(
        address _beneficiary,
        uint256 _start,
        uint256 _cliff,
        uint256 _duration,
        uint256 _slicePeriodSeconds,
        bool _revokable,
        uint256 _amount
    ) internal {
        if (getWithdrawableAmount() < _amount) revert InsufficientTokensInContract();

        // _start should be no further away than 30 weeks
        if (_start > block.timestamp + 30 weeks) revert InvalidStart();

        // _duration should be at least 7 days and max 50 years
        if (_duration < 7 days || _duration > 50 * (365 days)) revert InvalidDuration();

        if (_amount == 0 || _amount > 2 ** 200) revert InvalidAmount();

        // _slicePeriodSeconds should be between 1 and 60 seconds
        if (_slicePeriodSeconds == 0 || _slicePeriodSeconds > 60) revert InvalidSlicePeriod();

        // _duration must be longer than _cliff
        if (_duration < _cliff) revert DurationShorterThanCliff();

        if (holdersVestingScheduleCount[_beneficiary] >= 100) revert TooManySchedulesForBeneficiary();

        bytes32 vestingScheduleId = computeVestingScheduleIdForAddressAndIndex(_beneficiary, holdersVestingScheduleCount[_beneficiary]++);
        vestingSchedules[vestingScheduleId] =
            VestingSchedule(_start + _cliff, _start, _duration, _slicePeriodSeconds, _amount, 0, Status.INITIALIZED, _beneficiary, _revokable);
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount + _amount;

        holdersVestedAmount[_beneficiary] = holdersVestedAmount[_beneficiary] + _amount;
        emit ScheduleCreated(vestingScheduleId, _beneficiary, _amount, _start, _cliff, _duration, _slicePeriodSeconds, _revokable);
        emit Transfer(address(0), _beneficiary, _amount);
    }

    /**
     * @notice Revokes the vesting schedule for given identifier.
     * @param vestingScheduleId the vesting schedule identifier
     */
    function revoke(bytes32 vestingScheduleId) external onlyRole(DEFAULT_ADMIN_ROLE) onlyIfVestingScheduleNotRevoked(vestingScheduleId) {
        VestingSchedule storage vestingSchedule = vestingSchedules[vestingScheduleId];
        if (!vestingSchedule.revokable) revert NotRevokable();
        if (_computeReleasableAmount(vestingSchedule) > 0) {
            _release(vestingScheduleId, _computeReleasableAmount(vestingSchedule));
        }
        uint256 unreleased = vestingSchedule.amountTotal - vestingSchedule.released;
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount - unreleased;
        holdersVestedAmount[vestingSchedule.beneficiary] = holdersVestedAmount[vestingSchedule.beneficiary] - unreleased;
        vestingSchedule.status = Status.REVOKED;
        emit ScheduleRevoked(vestingScheduleId);
        emit Transfer(vestingSchedule.beneficiary, address(0), unreleased);
    }

    /**
     * @notice Pauses or unpauses the creation of new vesting schedules and the purchase of those vesting schedules
     * @param paused true if the creation of vesting schedules and purchase of those should be paused, false otherwise
     */
    function setPaused(bool paused) external onlyRole(DEFAULT_ADMIN_ROLE) {
        if (paused) {
            _pause();
        } else {
            _unpause();
        }
    }

    /**
     * @notice Withdraw the specified amount if possible.
     * @param amount the amount to withdraw
     */
    function withdraw(uint256 amount) external nonReentrant onlyRole(DEFAULT_ADMIN_ROLE) {
        if (amount > getWithdrawableAmount()) revert InsufficientTokensInContract();
        underlyingToken.safeTransfer(msg.sender, amount);
    }

    /**
     * @notice Internal function for releasing vested amount of tokens.
     * @param vestingScheduleId the vesting schedule identifier
     * @param amount the amount to release
     */
    function _release(bytes32 vestingScheduleId, uint256 amount) internal {
        VestingSchedule storage vestingSchedule = vestingSchedules[vestingScheduleId];
        bool isBeneficiary = msg.sender == vestingSchedule.beneficiary;
        bool isOwner = msg.sender == owner();
        if (!isBeneficiary && !isOwner) revert Unauthorized();
        if (amount > _computeReleasableAmount(vestingSchedule)) revert InsufficientReleasableTokens();
        vestingSchedule.released = vestingSchedule.released + amount;
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount - amount;
        holdersVestedAmount[vestingSchedule.beneficiary] = holdersVestedAmount[vestingSchedule.beneficiary] - amount;
        emit TokensReleased(vestingScheduleId, vestingSchedule.beneficiary, amount);
        underlyingToken.safeTransfer(vestingSchedule.beneficiary, amount);
        emit Transfer(vestingSchedule.beneficiary, address(0), amount);
    }

    /**
     * @notice Release vested amount of tokens.
     * @param vestingScheduleId the vesting schedule identifier
     * @param amount the amount to release
     */
    function release(bytes32 vestingScheduleId, uint256 amount) external nonReentrant onlyIfVestingScheduleNotRevoked(vestingScheduleId) {
        _release(vestingScheduleId, amount);
    }

    /**
     * @notice Release all available tokens for holder address
     * @param holder address of the holder & beneficiary
     */
    function releaseAvailableTokensForHolder(address holder) external nonReentrant {
        if (msg.sender != holder && msg.sender != owner()) revert Unauthorized();
        uint256 vestingScheduleCount = holdersVestingScheduleCount[holder];
        for (uint256 i = 0; i < vestingScheduleCount; i++) {
            bytes32 vestingScheduleId = computeVestingScheduleIdForAddressAndIndex(holder, i);
            uint256 releasable = _computeReleasableAmount(vestingSchedules[vestingScheduleId]);
            if (releasable > 0) {
                _release(vestingScheduleId, releasable);
            }
        }
    }

    /// GETTERS ///

    /**
     * @notice Computes the vested amount of tokens for the given vesting schedule identifier.
     * @return the vested amount
     */
    function computeReleasableAmount(bytes32 vestingScheduleId) external view onlyIfVestingScheduleNotRevoked(vestingScheduleId) returns (uint256) {
        return _computeReleasableAmount(vestingSchedules[vestingScheduleId]);
    }

    /**
     * @notice Returns the vesting schedule information for a given identifier.
     * @return the vesting schedule structure information
     */
    function getVestingSchedule(bytes32 vestingScheduleId) public view returns (VestingSchedule memory) {
        return vestingSchedules[vestingScheduleId];
    }

    /**
     * @notice Returns the amount of base tokens that can be withdrawn by the owner.
     * @return the amount of tokens
     */
    function getWithdrawableAmount() public view returns (uint256) {
        return underlyingToken.balanceOf(address(this)) - vestingSchedulesTotalAmount;
    }

    /**
     * @notice Computes the vesting schedule identifier for an address and an index.
     */
    function computeVestingScheduleIdForAddressAndIndex(address holder, uint256 index) public pure returns (bytes32) {
        return keccak256(abi.encodePacked(holder, index));
    }

    /**
     * @dev Computes the releasable amount of tokens for a vesting schedule.
     * @return the amount of releasable tokens
     */
    function _computeReleasableAmount(VestingSchedule storage vestingSchedule) internal view returns (uint256) {
        uint256 currentTime = block.timestamp;
        //slither-disable-next-line incorrect-equality
        if (currentTime < vestingSchedule.cliff || vestingSchedule.status == Status.REVOKED) {
            return 0;
        } else if (currentTime >= vestingSchedule.start + vestingSchedule.duration) {
            return vestingSchedule.amountTotal - vestingSchedule.released;
        } else {
            uint256 timeFromStart = currentTime - vestingSchedule.start;
            uint256 secondsPerSlice = vestingSchedule.slicePeriodSeconds;
            uint256 vestedSlicePeriods = timeFromStart / secondsPerSlice;
            // Disable warning: duration and token amounts are checked in schedule creation and prevent underflow/overflow
            //slither-disable-next-line divide-before-multiply
            uint256 vestedSeconds = vestedSlicePeriods * secondsPerSlice;
            // Disable warning: duration and token amounts are checked in schedule creation and prevent underflow/overflow
            //slither-disable-next-line divide-before-multiply
            uint256 vestedAmount = vestingSchedule.amountTotal * vestedSeconds / vestingSchedule.duration;
            return vestedAmount - vestingSchedule.released;
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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:
 *
 * ```solidity
 * 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}:
 *
 * ```solidity
 * 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. We recommend using {AccessControlDefaultAdminRules}
 * to enforce additional security measures for this role.
 */
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(account),
                        " 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());
        }
    }
}

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

pragma solidity ^0.8.0;

import "./IAccessControl.sol";

/**
 * @dev External interface of AccessControlDefaultAdminRules declared to support ERC165 detection.
 *
 * _Available since v4.9._
 */
interface IAccessControlDefaultAdminRules is IAccessControl {
    /**
     * @dev Emitted when a {defaultAdmin} transfer is started, setting `newAdmin` as the next
     * address to become the {defaultAdmin} by calling {acceptDefaultAdminTransfer} only after `acceptSchedule`
     * passes.
     */
    event DefaultAdminTransferScheduled(address indexed newAdmin, uint48 acceptSchedule);

    /**
     * @dev Emitted when a {pendingDefaultAdmin} is reset if it was never accepted, regardless of its schedule.
     */
    event DefaultAdminTransferCanceled();

    /**
     * @dev Emitted when a {defaultAdminDelay} change is started, setting `newDelay` as the next
     * delay to be applied between default admin transfer after `effectSchedule` has passed.
     */
    event DefaultAdminDelayChangeScheduled(uint48 newDelay, uint48 effectSchedule);

    /**
     * @dev Emitted when a {pendingDefaultAdminDelay} is reset if its schedule didn't pass.
     */
    event DefaultAdminDelayChangeCanceled();

    /**
     * @dev Returns the address of the current `DEFAULT_ADMIN_ROLE` holder.
     */
    function defaultAdmin() external view returns (address);

    /**
     * @dev Returns a tuple of a `newAdmin` and an accept schedule.
     *
     * After the `schedule` passes, the `newAdmin` will be able to accept the {defaultAdmin} role
     * by calling {acceptDefaultAdminTransfer}, completing the role transfer.
     *
     * A zero value only in `acceptSchedule` indicates no pending admin transfer.
     *
     * NOTE: A zero address `newAdmin` means that {defaultAdmin} is being renounced.
     */
    function pendingDefaultAdmin() external view returns (address newAdmin, uint48 acceptSchedule);

    /**
     * @dev Returns the delay required to schedule the acceptance of a {defaultAdmin} transfer started.
     *
     * This delay will be added to the current timestamp when calling {beginDefaultAdminTransfer} to set
     * the acceptance schedule.
     *
     * NOTE: If a delay change has been scheduled, it will take effect as soon as the schedule passes, making this
     * function returns the new delay. See {changeDefaultAdminDelay}.
     */
    function defaultAdminDelay() external view returns (uint48);

    /**
     * @dev Returns a tuple of `newDelay` and an effect schedule.
     *
     * After the `schedule` passes, the `newDelay` will get into effect immediately for every
     * new {defaultAdmin} transfer started with {beginDefaultAdminTransfer}.
     *
     * A zero value only in `effectSchedule` indicates no pending delay change.
     *
     * NOTE: A zero value only for `newDelay` means that the next {defaultAdminDelay}
     * will be zero after the effect schedule.
     */
    function pendingDefaultAdminDelay() external view returns (uint48 newDelay, uint48 effectSchedule);

    /**
     * @dev Starts a {defaultAdmin} transfer by setting a {pendingDefaultAdmin} scheduled for acceptance
     * after the current timestamp plus a {defaultAdminDelay}.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * Emits a DefaultAdminRoleChangeStarted event.
     */
    function beginDefaultAdminTransfer(address newAdmin) external;

    /**
     * @dev Cancels a {defaultAdmin} transfer previously started with {beginDefaultAdminTransfer}.
     *
     * A {pendingDefaultAdmin} not yet accepted can also be cancelled with this function.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * May emit a DefaultAdminTransferCanceled event.
     */
    function cancelDefaultAdminTransfer() external;

    /**
     * @dev Completes a {defaultAdmin} transfer previously started with {beginDefaultAdminTransfer}.
     *
     * After calling the function:
     *
     * - `DEFAULT_ADMIN_ROLE` should be granted to the caller.
     * - `DEFAULT_ADMIN_ROLE` should be revoked from the previous holder.
     * - {pendingDefaultAdmin} should be reset to zero values.
     *
     * Requirements:
     *
     * - Only can be called by the {pendingDefaultAdmin}'s `newAdmin`.
     * - The {pendingDefaultAdmin}'s `acceptSchedule` should've passed.
     */
    function acceptDefaultAdminTransfer() external;

    /**
     * @dev Initiates a {defaultAdminDelay} update by setting a {pendingDefaultAdminDelay} scheduled for getting
     * into effect after the current timestamp plus a {defaultAdminDelay}.
     *
     * This function guarantees that any call to {beginDefaultAdminTransfer} done between the timestamp this
     * method is called and the {pendingDefaultAdminDelay} effect schedule will use the current {defaultAdminDelay}
     * set before calling.
     *
     * The {pendingDefaultAdminDelay}'s effect schedule is defined in a way that waiting until the schedule and then
     * calling {beginDefaultAdminTransfer} with the new delay will take at least the same as another {defaultAdmin}
     * complete transfer (including acceptance).
     *
     * The schedule is designed for two scenarios:
     *
     * - When the delay is changed for a larger one the schedule is `block.timestamp + newDelay` capped by
     * {defaultAdminDelayIncreaseWait}.
     * - When the delay is changed for a shorter one, the schedule is `block.timestamp + (current delay - new delay)`.
     *
     * A {pendingDefaultAdminDelay} that never got into effect will be canceled in favor of a new scheduled change.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * Emits a DefaultAdminDelayChangeScheduled event and may emit a DefaultAdminDelayChangeCanceled event.
     */
    function changeDefaultAdminDelay(uint48 newDelay) external;

    /**
     * @dev Cancels a scheduled {defaultAdminDelay} change.
     *
     * Requirements:
     *
     * - Only can be called by the current {defaultAdmin}.
     *
     * May emit a DefaultAdminDelayChangeCanceled event.
     */
    function rollbackDefaultAdminDelay() external;

    /**
     * @dev Maximum time in seconds for an increase to {defaultAdminDelay} (that is scheduled using {changeDefaultAdminDelay})
     * to take effect. Default to 5 days.
     *
     * When the {defaultAdminDelay} is scheduled to be increased, it goes into effect after the new delay has passed with
     * the purpose of giving enough time for reverting any accidental change (i.e. using milliseconds instead of seconds)
     * that may lock the contract. However, to avoid excessive schedules, the wait is capped by this function and it can
     * be overrode for a custom {defaultAdminDelay} increase scheduling.
     *
     * IMPORTANT: Make sure to add a reasonable amount of time while overriding this value, otherwise,
     * there's a risk of setting a high new delay that goes into effect almost immediately without the
     * possibility of human intervention in the case of an input error (eg. set milliseconds instead of seconds).
     */
    function defaultAdminDelayIncreaseWait() external view returns (uint48);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SafeCast.sol)
// This file was procedurally generated from scripts/generate/templates/SafeCast.js.

pragma solidity ^0.8.0;

/**
 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
 * checks.
 *
 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
 * easily result in undesired exploitation or bugs, since developers usually
 * assume that overflows raise errors. `SafeCast` restores this intuition by
 * reverting the transaction when such an operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 *
 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
 * all math on `uint256` and `int256` and then downcasting.
 */
library SafeCast {
    /**
     * @dev Returns the downcasted uint248 from uint256, reverting on
     * overflow (when the input is greater than largest uint248).
     *
     * Counterpart to Solidity's `uint248` operator.
     *
     * Requirements:
     *
     * - input must fit into 248 bits
     *
     * _Available since v4.7._
     */
    function toUint248(uint256 value) internal pure returns (uint248) {
        require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits");
        return uint248(value);
    }

    /**
     * @dev Returns the downcasted uint240 from uint256, reverting on
     * overflow (when the input is greater than largest uint240).
     *
     * Counterpart to Solidity's `uint240` operator.
     *
     * Requirements:
     *
     * - input must fit into 240 bits
     *
     * _Available since v4.7._
     */
    function toUint240(uint256 value) internal pure returns (uint240) {
        require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits");
        return uint240(value);
    }

    /**
     * @dev Returns the downcasted uint232 from uint256, reverting on
     * overflow (when the input is greater than largest uint232).
     *
     * Counterpart to Solidity's `uint232` operator.
     *
     * Requirements:
     *
     * - input must fit into 232 bits
     *
     * _Available since v4.7._
     */
    function toUint232(uint256 value) internal pure returns (uint232) {
        require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits");
        return uint232(value);
    }

    /**
     * @dev Returns the downcasted uint224 from uint256, reverting on
     * overflow (when the input is greater than largest uint224).
     *
     * Counterpart to Solidity's `uint224` operator.
     *
     * Requirements:
     *
     * - input must fit into 224 bits
     *
     * _Available since v4.2._
     */
    function toUint224(uint256 value) internal pure returns (uint224) {
        require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
        return uint224(value);
    }

    /**
     * @dev Returns the downcasted uint216 from uint256, reverting on
     * overflow (when the input is greater than largest uint216).
     *
     * Counterpart to Solidity's `uint216` operator.
     *
     * Requirements:
     *
     * - input must fit into 216 bits
     *
     * _Available since v4.7._
     */
    function toUint216(uint256 value) internal pure returns (uint216) {
        require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits");
        return uint216(value);
    }

    /**
     * @dev Returns the downcasted uint208 from uint256, reverting on
     * overflow (when the input is greater than largest uint208).
     *
     * Counterpart to Solidity's `uint208` operator.
     *
     * Requirements:
     *
     * - input must fit into 208 bits
     *
     * _Available since v4.7._
     */
    function toUint208(uint256 value) internal pure returns (uint208) {
        require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits");
        return uint208(value);
    }

    /**
     * @dev Returns the downcasted uint200 from uint256, reverting on
     * overflow (when the input is greater than largest uint200).
     *
     * Counterpart to Solidity's `uint200` operator.
     *
     * Requirements:
     *
     * - input must fit into 200 bits
     *
     * _Available since v4.7._
     */
    function toUint200(uint256 value) internal pure returns (uint200) {
        require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits");
        return uint200(value);
    }

    /**
     * @dev Returns the downcasted uint192 from uint256, reverting on
     * overflow (when the input is greater than largest uint192).
     *
     * Counterpart to Solidity's `uint192` operator.
     *
     * Requirements:
     *
     * - input must fit into 192 bits
     *
     * _Available since v4.7._
     */
    function toUint192(uint256 value) internal pure returns (uint192) {
        require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits");
        return uint192(value);
    }

    /**
     * @dev Returns the downcasted uint184 from uint256, reverting on
     * overflow (when the input is greater than largest uint184).
     *
     * Counterpart to Solidity's `uint184` operator.
     *
     * Requirements:
     *
     * - input must fit into 184 bits
     *
     * _Available since v4.7._
     */
    function toUint184(uint256 value) internal pure returns (uint184) {
        require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits");
        return uint184(value);
    }

    /**
     * @dev Returns the downcasted uint176 from uint256, reverting on
     * overflow (when the input is greater than largest uint176).
     *
     * Counterpart to Solidity's `uint176` operator.
     *
     * Requirements:
     *
     * - input must fit into 176 bits
     *
     * _Available since v4.7._
     */
    function toUint176(uint256 value) internal pure returns (uint176) {
        require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits");
        return uint176(value);
    }

    /**
     * @dev Returns the downcasted uint168 from uint256, reverting on
     * overflow (when the input is greater than largest uint168).
     *
     * Counterpart to Solidity's `uint168` operator.
     *
     * Requirements:
     *
     * - input must fit into 168 bits
     *
     * _Available since v4.7._
     */
    function toUint168(uint256 value) internal pure returns (uint168) {
        require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits");
        return uint168(value);
    }

    /**
     * @dev Returns the downcasted uint160 from uint256, reverting on
     * overflow (when the input is greater than largest uint160).
     *
     * Counterpart to Solidity's `uint160` operator.
     *
     * Requirements:
     *
     * - input must fit into 160 bits
     *
     * _Available since v4.7._
     */
    function toUint160(uint256 value) internal pure returns (uint160) {
        require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits");
        return uint160(value);
    }

    /**
     * @dev Returns the downcasted uint152 from uint256, reverting on
     * overflow (when the input is greater than largest uint152).
     *
     * Counterpart to Solidity's `uint152` operator.
     *
     * Requirements:
     *
     * - input must fit into 152 bits
     *
     * _Available since v4.7._
     */
    function toUint152(uint256 value) internal pure returns (uint152) {
        require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits");
        return uint152(value);
    }

    /**
     * @dev Returns the downcasted uint144 from uint256, reverting on
     * overflow (when the input is greater than largest uint144).
     *
     * Counterpart to Solidity's `uint144` operator.
     *
     * Requirements:
     *
     * - input must fit into 144 bits
     *
     * _Available since v4.7._
     */
    function toUint144(uint256 value) internal pure returns (uint144) {
        require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits");
        return uint144(value);
    }

    /**
     * @dev Returns the downcasted uint136 from uint256, reverting on
     * overflow (when the input is greater than largest uint136).
     *
     * Counterpart to Solidity's `uint136` operator.
     *
     * Requirements:
     *
     * - input must fit into 136 bits
     *
     * _Available since v4.7._
     */
    function toUint136(uint256 value) internal pure returns (uint136) {
        require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits");
        return uint136(value);
    }

    /**
     * @dev Returns the downcasted uint128 from uint256, reverting on
     * overflow (when the input is greater than largest uint128).
     *
     * Counterpart to Solidity's `uint128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v2.5._
     */
    function toUint128(uint256 value) internal pure returns (uint128) {
        require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
        return uint128(value);
    }

    /**
     * @dev Returns the downcasted uint120 from uint256, reverting on
     * overflow (when the input is greater than largest uint120).
     *
     * Counterpart to Solidity's `uint120` operator.
     *
     * Requirements:
     *
     * - input must fit into 120 bits
     *
     * _Available since v4.7._
     */
    function toUint120(uint256 value) internal pure returns (uint120) {
        require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits");
        return uint120(value);
    }

    /**
     * @dev Returns the downcasted uint112 from uint256, reverting on
     * overflow (when the input is greater than largest uint112).
     *
     * Counterpart to Solidity's `uint112` operator.
     *
     * Requirements:
     *
     * - input must fit into 112 bits
     *
     * _Available since v4.7._
     */
    function toUint112(uint256 value) internal pure returns (uint112) {
        require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits");
        return uint112(value);
    }

    /**
     * @dev Returns the downcasted uint104 from uint256, reverting on
     * overflow (when the input is greater than largest uint104).
     *
     * Counterpart to Solidity's `uint104` operator.
     *
     * Requirements:
     *
     * - input must fit into 104 bits
     *
     * _Available since v4.7._
     */
    function toUint104(uint256 value) internal pure returns (uint104) {
        require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits");
        return uint104(value);
    }

    /**
     * @dev Returns the downcasted uint96 from uint256, reverting on
     * overflow (when the input is greater than largest uint96).
     *
     * Counterpart to Solidity's `uint96` operator.
     *
     * Requirements:
     *
     * - input must fit into 96 bits
     *
     * _Available since v4.2._
     */
    function toUint96(uint256 value) internal pure returns (uint96) {
        require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
        return uint96(value);
    }

    /**
     * @dev Returns the downcasted uint88 from uint256, reverting on
     * overflow (when the input is greater than largest uint88).
     *
     * Counterpart to Solidity's `uint88` operator.
     *
     * Requirements:
     *
     * - input must fit into 88 bits
     *
     * _Available since v4.7._
     */
    function toUint88(uint256 value) internal pure returns (uint88) {
        require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits");
        return uint88(value);
    }

    /**
     * @dev Returns the downcasted uint80 from uint256, reverting on
     * overflow (when the input is greater than largest uint80).
     *
     * Counterpart to Solidity's `uint80` operator.
     *
     * Requirements:
     *
     * - input must fit into 80 bits
     *
     * _Available since v4.7._
     */
    function toUint80(uint256 value) internal pure returns (uint80) {
        require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits");
        return uint80(value);
    }

    /**
     * @dev Returns the downcasted uint72 from uint256, reverting on
     * overflow (when the input is greater than largest uint72).
     *
     * Counterpart to Solidity's `uint72` operator.
     *
     * Requirements:
     *
     * - input must fit into 72 bits
     *
     * _Available since v4.7._
     */
    function toUint72(uint256 value) internal pure returns (uint72) {
        require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits");
        return uint72(value);
    }

    /**
     * @dev Returns the downcasted uint64 from uint256, reverting on
     * overflow (when the input is greater than largest uint64).
     *
     * Counterpart to Solidity's `uint64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v2.5._
     */
    function toUint64(uint256 value) internal pure returns (uint64) {
        require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
        return uint64(value);
    }

    /**
     * @dev Returns the downcasted uint56 from uint256, reverting on
     * overflow (when the input is greater than largest uint56).
     *
     * Counterpart to Solidity's `uint56` operator.
     *
     * Requirements:
     *
     * - input must fit into 56 bits
     *
     * _Available since v4.7._
     */
    function toUint56(uint256 value) internal pure returns (uint56) {
        require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits");
        return uint56(value);
    }

    /**
     * @dev Returns the downcasted uint48 from uint256, reverting on
     * overflow (when the input is greater than largest uint48).
     *
     * Counterpart to Solidity's `uint48` operator.
     *
     * Requirements:
     *
     * - input must fit into 48 bits
     *
     * _Available since v4.7._
     */
    function toUint48(uint256 value) internal pure returns (uint48) {
        require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits");
        return uint48(value);
    }

    /**
     * @dev Returns the downcasted uint40 from uint256, reverting on
     * overflow (when the input is greater than largest uint40).
     *
     * Counterpart to Solidity's `uint40` operator.
     *
     * Requirements:
     *
     * - input must fit into 40 bits
     *
     * _Available since v4.7._
     */
    function toUint40(uint256 value) internal pure returns (uint40) {
        require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits");
        return uint40(value);
    }

    /**
     * @dev Returns the downcasted uint32 from uint256, reverting on
     * overflow (when the input is greater than largest uint32).
     *
     * Counterpart to Solidity's `uint32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v2.5._
     */
    function toUint32(uint256 value) internal pure returns (uint32) {
        require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
        return uint32(value);
    }

    /**
     * @dev Returns the downcasted uint24 from uint256, reverting on
     * overflow (when the input is greater than largest uint24).
     *
     * Counterpart to Solidity's `uint24` operator.
     *
     * Requirements:
     *
     * - input must fit into 24 bits
     *
     * _Available since v4.7._
     */
    function toUint24(uint256 value) internal pure returns (uint24) {
        require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits");
        return uint24(value);
    }

    /**
     * @dev Returns the downcasted uint16 from uint256, reverting on
     * overflow (when the input is greater than largest uint16).
     *
     * Counterpart to Solidity's `uint16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v2.5._
     */
    function toUint16(uint256 value) internal pure returns (uint16) {
        require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
        return uint16(value);
    }

    /**
     * @dev Returns the downcasted uint8 from uint256, reverting on
     * overflow (when the input is greater than largest uint8).
     *
     * Counterpart to Solidity's `uint8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits
     *
     * _Available since v2.5._
     */
    function toUint8(uint256 value) internal pure returns (uint8) {
        require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
        return uint8(value);
    }

    /**
     * @dev Converts a signed int256 into an unsigned uint256.
     *
     * Requirements:
     *
     * - input must be greater than or equal to 0.
     *
     * _Available since v3.0._
     */
    function toUint256(int256 value) internal pure returns (uint256) {
        require(value >= 0, "SafeCast: value must be positive");
        return uint256(value);
    }

    /**
     * @dev Returns the downcasted int248 from int256, reverting on
     * overflow (when the input is less than smallest int248 or
     * greater than largest int248).
     *
     * Counterpart to Solidity's `int248` operator.
     *
     * Requirements:
     *
     * - input must fit into 248 bits
     *
     * _Available since v4.7._
     */
    function toInt248(int256 value) internal pure returns (int248 downcasted) {
        downcasted = int248(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 248 bits");
    }

    /**
     * @dev Returns the downcasted int240 from int256, reverting on
     * overflow (when the input is less than smallest int240 or
     * greater than largest int240).
     *
     * Counterpart to Solidity's `int240` operator.
     *
     * Requirements:
     *
     * - input must fit into 240 bits
     *
     * _Available since v4.7._
     */
    function toInt240(int256 value) internal pure returns (int240 downcasted) {
        downcasted = int240(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 240 bits");
    }

    /**
     * @dev Returns the downcasted int232 from int256, reverting on
     * overflow (when the input is less than smallest int232 or
     * greater than largest int232).
     *
     * Counterpart to Solidity's `int232` operator.
     *
     * Requirements:
     *
     * - input must fit into 232 bits
     *
     * _Available since v4.7._
     */
    function toInt232(int256 value) internal pure returns (int232 downcasted) {
        downcasted = int232(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 232 bits");
    }

    /**
     * @dev Returns the downcasted int224 from int256, reverting on
     * overflow (when the input is less than smallest int224 or
     * greater than largest int224).
     *
     * Counterpart to Solidity's `int224` operator.
     *
     * Requirements:
     *
     * - input must fit into 224 bits
     *
     * _Available since v4.7._
     */
    function toInt224(int256 value) internal pure returns (int224 downcasted) {
        downcasted = int224(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 224 bits");
    }

    /**
     * @dev Returns the downcasted int216 from int256, reverting on
     * overflow (when the input is less than smallest int216 or
     * greater than largest int216).
     *
     * Counterpart to Solidity's `int216` operator.
     *
     * Requirements:
     *
     * - input must fit into 216 bits
     *
     * _Available since v4.7._
     */
    function toInt216(int256 value) internal pure returns (int216 downcasted) {
        downcasted = int216(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 216 bits");
    }

    /**
     * @dev Returns the downcasted int208 from int256, reverting on
     * overflow (when the input is less than smallest int208 or
     * greater than largest int208).
     *
     * Counterpart to Solidity's `int208` operator.
     *
     * Requirements:
     *
     * - input must fit into 208 bits
     *
     * _Available since v4.7._
     */
    function toInt208(int256 value) internal pure returns (int208 downcasted) {
        downcasted = int208(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 208 bits");
    }

    /**
     * @dev Returns the downcasted int200 from int256, reverting on
     * overflow (when the input is less than smallest int200 or
     * greater than largest int200).
     *
     * Counterpart to Solidity's `int200` operator.
     *
     * Requirements:
     *
     * - input must fit into 200 bits
     *
     * _Available since v4.7._
     */
    function toInt200(int256 value) internal pure returns (int200 downcasted) {
        downcasted = int200(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 200 bits");
    }

    /**
     * @dev Returns the downcasted int192 from int256, reverting on
     * overflow (when the input is less than smallest int192 or
     * greater than largest int192).
     *
     * Counterpart to Solidity's `int192` operator.
     *
     * Requirements:
     *
     * - input must fit into 192 bits
     *
     * _Available since v4.7._
     */
    function toInt192(int256 value) internal pure returns (int192 downcasted) {
        downcasted = int192(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 192 bits");
    }

    /**
     * @dev Returns the downcasted int184 from int256, reverting on
     * overflow (when the input is less than smallest int184 or
     * greater than largest int184).
     *
     * Counterpart to Solidity's `int184` operator.
     *
     * Requirements:
     *
     * - input must fit into 184 bits
     *
     * _Available since v4.7._
     */
    function toInt184(int256 value) internal pure returns (int184 downcasted) {
        downcasted = int184(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 184 bits");
    }

    /**
     * @dev Returns the downcasted int176 from int256, reverting on
     * overflow (when the input is less than smallest int176 or
     * greater than largest int176).
     *
     * Counterpart to Solidity's `int176` operator.
     *
     * Requirements:
     *
     * - input must fit into 176 bits
     *
     * _Available since v4.7._
     */
    function toInt176(int256 value) internal pure returns (int176 downcasted) {
        downcasted = int176(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 176 bits");
    }

    /**
     * @dev Returns the downcasted int168 from int256, reverting on
     * overflow (when the input is less than smallest int168 or
     * greater than largest int168).
     *
     * Counterpart to Solidity's `int168` operator.
     *
     * Requirements:
     *
     * - input must fit into 168 bits
     *
     * _Available since v4.7._
     */
    function toInt168(int256 value) internal pure returns (int168 downcasted) {
        downcasted = int168(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 168 bits");
    }

    /**
     * @dev Returns the downcasted int160 from int256, reverting on
     * overflow (when the input is less than smallest int160 or
     * greater than largest int160).
     *
     * Counterpart to Solidity's `int160` operator.
     *
     * Requirements:
     *
     * - input must fit into 160 bits
     *
     * _Available since v4.7._
     */
    function toInt160(int256 value) internal pure returns (int160 downcasted) {
        downcasted = int160(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 160 bits");
    }

    /**
     * @dev Returns the downcasted int152 from int256, reverting on
     * overflow (when the input is less than smallest int152 or
     * greater than largest int152).
     *
     * Counterpart to Solidity's `int152` operator.
     *
     * Requirements:
     *
     * - input must fit into 152 bits
     *
     * _Available since v4.7._
     */
    function toInt152(int256 value) internal pure returns (int152 downcasted) {
        downcasted = int152(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 152 bits");
    }

    /**
     * @dev Returns the downcasted int144 from int256, reverting on
     * overflow (when the input is less than smallest int144 or
     * greater than largest int144).
     *
     * Counterpart to Solidity's `int144` operator.
     *
     * Requirements:
     *
     * - input must fit into 144 bits
     *
     * _Available since v4.7._
     */
    function toInt144(int256 value) internal pure returns (int144 downcasted) {
        downcasted = int144(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 144 bits");
    }

    /**
     * @dev Returns the downcasted int136 from int256, reverting on
     * overflow (when the input is less than smallest int136 or
     * greater than largest int136).
     *
     * Counterpart to Solidity's `int136` operator.
     *
     * Requirements:
     *
     * - input must fit into 136 bits
     *
     * _Available since v4.7._
     */
    function toInt136(int256 value) internal pure returns (int136 downcasted) {
        downcasted = int136(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 136 bits");
    }

    /**
     * @dev Returns the downcasted int128 from int256, reverting on
     * overflow (when the input is less than smallest int128 or
     * greater than largest int128).
     *
     * Counterpart to Solidity's `int128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v3.1._
     */
    function toInt128(int256 value) internal pure returns (int128 downcasted) {
        downcasted = int128(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 128 bits");
    }

    /**
     * @dev Returns the downcasted int120 from int256, reverting on
     * overflow (when the input is less than smallest int120 or
     * greater than largest int120).
     *
     * Counterpart to Solidity's `int120` operator.
     *
     * Requirements:
     *
     * - input must fit into 120 bits
     *
     * _Available since v4.7._
     */
    function toInt120(int256 value) internal pure returns (int120 downcasted) {
        downcasted = int120(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 120 bits");
    }

    /**
     * @dev Returns the downcasted int112 from int256, reverting on
     * overflow (when the input is less than smallest int112 or
     * greater than largest int112).
     *
     * Counterpart to Solidity's `int112` operator.
     *
     * Requirements:
     *
     * - input must fit into 112 bits
     *
     * _Available since v4.7._
     */
    function toInt112(int256 value) internal pure returns (int112 downcasted) {
        downcasted = int112(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 112 bits");
    }

    /**
     * @dev Returns the downcasted int104 from int256, reverting on
     * overflow (when the input is less than smallest int104 or
     * greater than largest int104).
     *
     * Counterpart to Solidity's `int104` operator.
     *
     * Requirements:
     *
     * - input must fit into 104 bits
     *
     * _Available since v4.7._
     */
    function toInt104(int256 value) internal pure returns (int104 downcasted) {
        downcasted = int104(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 104 bits");
    }

    /**
     * @dev Returns the downcasted int96 from int256, reverting on
     * overflow (when the input is less than smallest int96 or
     * greater than largest int96).
     *
     * Counterpart to Solidity's `int96` operator.
     *
     * Requirements:
     *
     * - input must fit into 96 bits
     *
     * _Available since v4.7._
     */
    function toInt96(int256 value) internal pure returns (int96 downcasted) {
        downcasted = int96(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 96 bits");
    }

    /**
     * @dev Returns the downcasted int88 from int256, reverting on
     * overflow (when the input is less than smallest int88 or
     * greater than largest int88).
     *
     * Counterpart to Solidity's `int88` operator.
     *
     * Requirements:
     *
     * - input must fit into 88 bits
     *
     * _Available since v4.7._
     */
    function toInt88(int256 value) internal pure returns (int88 downcasted) {
        downcasted = int88(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 88 bits");
    }

    /**
     * @dev Returns the downcasted int80 from int256, reverting on
     * overflow (when the input is less than smallest int80 or
     * greater than largest int80).
     *
     * Counterpart to Solidity's `int80` operator.
     *
     * Requirements:
     *
     * - input must fit into 80 bits
     *
     * _Available since v4.7._
     */
    function toInt80(int256 value) internal pure returns (int80 downcasted) {
        downcasted = int80(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 80 bits");
    }

    /**
     * @dev Returns the downcasted int72 from int256, reverting on
     * overflow (when the input is less than smallest int72 or
     * greater than largest int72).
     *
     * Counterpart to Solidity's `int72` operator.
     *
     * Requirements:
     *
     * - input must fit into 72 bits
     *
     * _Available since v4.7._
     */
    function toInt72(int256 value) internal pure returns (int72 downcasted) {
        downcasted = int72(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 72 bits");
    }

    /**
     * @dev Returns the downcasted int64 from int256, reverting on
     * overflow (when the input is less than smallest int64 or
     * greater than largest int64).
     *
     * Counterpart to Solidity's `int64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v3.1._
     */
    function toInt64(int256 value) internal pure returns (int64 downcasted) {
        downcasted = int64(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 64 bits");
    }

    /**
     * @dev Returns the downcasted int56 from int256, reverting on
     * overflow (when the input is less than smallest int56 or
     * greater than largest int56).
     *
     * Counterpart to Solidity's `int56` operator.
     *
     * Requirements:
     *
     * - input must fit into 56 bits
     *
     * _Available since v4.7._
     */
    function toInt56(int256 value) internal pure returns (int56 downcasted) {
        downcasted = int56(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 56 bits");
    }

    /**
     * @dev Returns the downcasted int48 from int256, reverting on
     * overflow (when the input is less than smallest int48 or
     * greater than largest int48).
     *
     * Counterpart to Solidity's `int48` operator.
     *
     * Requirements:
     *
     * - input must fit into 48 bits
     *
     * _Available since v4.7._
     */
    function toInt48(int256 value) internal pure returns (int48 downcasted) {
        downcasted = int48(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 48 bits");
    }

    /**
     * @dev Returns the downcasted int40 from int256, reverting on
     * overflow (when the input is less than smallest int40 or
     * greater than largest int40).
     *
     * Counterpart to Solidity's `int40` operator.
     *
     * Requirements:
     *
     * - input must fit into 40 bits
     *
     * _Available since v4.7._
     */
    function toInt40(int256 value) internal pure returns (int40 downcasted) {
        downcasted = int40(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 40 bits");
    }

    /**
     * @dev Returns the downcasted int32 from int256, reverting on
     * overflow (when the input is less than smallest int32 or
     * greater than largest int32).
     *
     * Counterpart to Solidity's `int32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v3.1._
     */
    function toInt32(int256 value) internal pure returns (int32 downcasted) {
        downcasted = int32(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 32 bits");
    }

    /**
     * @dev Returns the downcasted int24 from int256, reverting on
     * overflow (when the input is less than smallest int24 or
     * greater than largest int24).
     *
     * Counterpart to Solidity's `int24` operator.
     *
     * Requirements:
     *
     * - input must fit into 24 bits
     *
     * _Available since v4.7._
     */
    function toInt24(int256 value) internal pure returns (int24 downcasted) {
        downcasted = int24(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 24 bits");
    }

    /**
     * @dev Returns the downcasted int16 from int256, reverting on
     * overflow (when the input is less than smallest int16 or
     * greater than largest int16).
     *
     * Counterpart to Solidity's `int16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v3.1._
     */
    function toInt16(int256 value) internal pure returns (int16 downcasted) {
        downcasted = int16(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 16 bits");
    }

    /**
     * @dev Returns the downcasted int8 from int256, reverting on
     * overflow (when the input is less than smallest int8 or
     * greater than largest int8).
     *
     * Counterpart to Solidity's `int8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits
     *
     * _Available since v3.1._
     */
    function toInt8(int256 value) internal pure returns (int8 downcasted) {
        downcasted = int8(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 8 bits");
    }

    /**
     * @dev Converts an unsigned uint256 into a signed int256.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxInt256.
     *
     * _Available since v3.0._
     */
    function toInt256(uint256 value) internal pure returns (int256) {
        // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
        require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
        return int256(value);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC5313.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface for the Light Contract Ownership Standard.
 *
 * A standardized minimal interface required to identify an account that controls a contract
 *
 * _Available since v4.9._
 */
interface IERC5313 {
    /**
     * @dev Gets the address of the owner.
     */
    function owner() external view returns (address);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
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].
     *
     * CAUTION: See Security Considerations above.
     */
    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);
}

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

pragma solidity ^0.8.1;

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

        return account.code.length > 0;
    }

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

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

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

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

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

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

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

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

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

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

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

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

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

// 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);
}

// 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());
    }
}

// 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;
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (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;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}

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

pragma solidity ^0.8.0;

import "./math/Math.sol";
import "./math/SignedMath.sol";

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

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `int256` to its ASCII `string` decimal representation.
     */
    function toString(int256 value) internal pure returns (string memory) {
        return string(abi.encodePacked(value < 0 ? "-" : "", toString(SignedMath.abs(value))));
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

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

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

    /**
     * @dev Returns true if the two strings are equal.
     */
    function equal(string memory a, string memory b) internal pure returns (bool) {
        return keccak256(bytes(a)) == keccak256(bytes(b));
    }
}

// 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;
    }
}

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

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                // The surrounding unchecked block does not change this fact.
                // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1, "Math: mulDiv overflow");

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10 ** 64) {
                value /= 10 ** 64;
                result += 64;
            }
            if (value >= 10 ** 32) {
                value /= 10 ** 32;
                result += 32;
            }
            if (value >= 10 ** 16) {
                value /= 10 ** 16;
                result += 16;
            }
            if (value >= 10 ** 8) {
                value /= 10 ** 8;
                result += 8;
            }
            if (value >= 10 ** 4) {
                value /= 10 ** 4;
                result += 4;
            }
            if (value >= 10 ** 2) {
                value /= 10 ** 2;
                result += 2;
            }
            if (value >= 10 ** 1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SignedMath.sol)

pragma solidity ^0.8.0;

/**
 * @dev Standard signed math utilities missing in the Solidity language.
 */
library SignedMath {
    /**
     * @dev Returns the largest of two signed numbers.
     */
    function max(int256 a, int256 b) internal pure returns (int256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two signed numbers.
     */
    function min(int256 a, int256 b) internal pure returns (int256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two signed numbers without overflow.
     * The result is rounded towards zero.
     */
    function average(int256 a, int256 b) internal pure returns (int256) {
        // Formula from the book "Hacker's Delight"
        int256 x = (a & b) + ((a ^ b) >> 1);
        return x + (int256(uint256(x) >> 255) & (a ^ b));
    }

    /**
     * @dev Returns the absolute unsigned value of a signed value.
     */
    function abs(int256 n) internal pure returns (uint256) {
        unchecked {
            // must be unchecked in order to support `n = type(int256).min`
            return uint256(n >= 0 ? n : -n);
        }
    }
}

// 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);
}