// File: contracts/boardoom/v2/ArthArthBoardroomV2.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import {Vault} from '../core/Vault.sol';
import {IERC20} from '@openzeppelin/contracts/contracts/token/ERC20/IERC20.sol';
import {VaultBoardroom} from '../core/VaultBoardroom.sol';

contract ArthArthBoardroomV2 is VaultBoardroom {
    constructor(IERC20 cash_, Vault arthVault_)
        VaultBoardroom(cash_, arthVault_)
    {}
}

// File: contracts/boardoom/core/Vault.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import {IERC20} from '@openzeppelin/contracts/contracts/token/ERC20/IERC20.sol';
import {
    AccessControl
} from '@openzeppelin/contracts/contracts/access/AccessControl.sol';
import {Operator} from '../../owner/Operator.sol';
import {SafeMath} from '@openzeppelin/contracts/contracts/math/SafeMath.sol';
import {StakingTimelock} from '../../timelock/StakingTimelock.sol';
import {IVaultBoardroom} from '../../interfaces/IVaultBoardroom.sol';

// import 'hardhat/console.sol';

/**
 * A vault is a contract that handles only the bonding & unbonding of tokens;
 * Rewards are handled by the boardroom contracts.
 */
contract Vault is AccessControl, StakingTimelock, Operator {
    using SafeMath for uint256;

    bytes32 public constant BOARDROOM_ROLE = keccak256('BOARDROOM_ROLE');

    /**
     * Data structures.
     */
    struct BondingDetail {
        uint256 firstBondedOn;
        uint256 latestBondedOn;
        uint256 previousBondedOn;
    }

    /**
     * State variables.
     */

    // The staked token.
    IERC20 public token;
    IVaultBoardroom public expansionBoardroom;
    IVaultBoardroom public contractionBoardroom;

    uint256 internal _totalSupply;
    bool public enableDeposits = true;
    uint256 internal _totalBondedSupply;

    mapping(address => uint256) internal _balances;

    /**
     * Modifier.
     */

    modifier stakerExists(address who) {
        require(balanceOf(who) > 0, 'Boardroom: The director does not exist');
        _;
    }

    /**
     * Events.
     */

    event Bonded(address indexed user, uint256 amount);
    event Unbonded(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);

    /**
     * Constructor.
     */
    constructor(IERC20 token_, uint256 duration_) StakingTimelock(duration_) {
        token = token_;
        _setupRole(DEFAULT_ADMIN_ROLE, _msgSender());
        _setupRole(BOARDROOM_ROLE, _msgSender());
    }

    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }

    function setBoardrooms(
        IVaultBoardroom expansionBoardroom_,
        IVaultBoardroom contractionBoardroom_
    ) public {
        expansionBoardroom = expansionBoardroom_;
        contractionBoardroom = contractionBoardroom_;
    }

    function balanceOf(address who) public view returns (uint256) {
        return _balances[who];
    }

    function totalBondedSupply() public view returns (uint256) {
        return _totalBondedSupply;
    }

    function balanceWithoutBonded(address who) public view returns (uint256) {
        uint256 unbondingAmount = getStakedAmount(msg.sender);
        return _balances[who].sub(unbondingAmount);
    }

    function toggleDeposits(bool val) external onlyOwner {
        enableDeposits = val;
    }

    function bond(uint256 amount) external virtual {
        _bond(msg.sender, amount);
    }

    function bondFor(address who, uint256 amount) external virtual {
        require(
            hasRole(BOARDROOM_ROLE, _msgSender()),
            'Vault: must have boardroom role to bond for someone else'
        );

        _bond(who, amount);
    }

    function unbond(uint256 amount) external virtual {
        _unbond(msg.sender, amount);
    }

    function withdraw() external virtual {
        _withdraw(msg.sender);
    }

    function _updateRewards(address who) private {
        if (address(expansionBoardroom) != address(0))
            expansionBoardroom.updateReward(who);

        if (address(contractionBoardroom) != address(0))
            contractionBoardroom.updateReward(who);
    }

    function _bond(address who, uint256 amount) private {
        require(amount > 0, 'Boardroom: cannot bond 0');
        require(enableDeposits, 'Boardroom: deposits are disabled');

        // console.log('vault bonding for %s', who);
        // console.log('vault bonding amount %s', amount);

        _totalSupply = _totalSupply.add(amount);
        _balances[who] = _balances[who].add(amount);
        _totalBondedSupply = _totalBondedSupply.add(amount);

        // NOTE: has to be pre-approved.
        token.transferFrom(who, address(this), amount);

        _updateRewards(who);

        emit Bonded(who, amount);
    }

    function _unbond(address who, uint256 amount) private stakerExists(who) {
        require(amount > 0, 'Boardroom: cannot unbond 0');

        uint256 directorShare = _balances[who];

        require(
            directorShare >= amount,
            'Boardroom: unbond request greater than staked amount'
        );

        _updateStakerDetails(who, amount);
        _updateRewards(who);

        _totalBondedSupply = _totalBondedSupply.sub(amount);

        emit Unbonded(who, amount);
    }

    function _withdraw(address who)
        private
        stakerExists(who)
        checkLockDurationFor(who)
    {
        uint256 directorShare = _balances[who];
        uint256 unbondingAmount = getStakedAmount(who);

        require(
            directorShare >= unbondingAmount,
            'Boardroom: withdraw request greater than unbonded amount'
        );

        // Reset the bonding timestamp, as we are withdrawing the entire amount.
        _totalSupply = _totalSupply.sub(unbondingAmount);
        _balances[who] = directorShare.sub(unbondingAmount);
        token.transfer(who, unbondingAmount);

        _updateStakerDetails(who, 0);
        _updateRewards(who);

        emit Withdrawn(who, unbondingAmount);
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

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

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

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

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

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

// File: contracts/boardoom/core/VaultBoardroom.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import {IERC20} from '@openzeppelin/contracts/contracts/token/ERC20/IERC20.sol';
import {Vault} from './Vault.sol';
import {SafeMath} from '@openzeppelin/contracts/contracts/math/SafeMath.sol';
import {Safe112} from '../../lib/Safe112.sol';
import {ContractGuard} from '../../utils/ContractGuard.sol';
import {Operator} from '../../owner/Operator.sol';
import {IBoardroom} from '../../interfaces/IBoardroom.sol';
import {IBasisAsset} from '../../interfaces/IBasisAsset.sol';

// import 'hardhat/console.sol';

contract VaultBoardroom is ContractGuard, Operator, IBoardroom {
    using Safe112 for uint112;
    using SafeMath for uint256;

    // The vault which has state of the stakes.
    Vault public vault;
    IERC20 public token;
    uint256 public currentEpoch = 1;

    BoardSnapshot[] public boardHistory;
    mapping(address => Boardseat) public directors;
    mapping(address => mapping(uint256 => BondingSnapshot))
        public bondingHistory;

    mapping(address => mapping(uint256 => uint256)) directorBalanceForEpoch;
    mapping(address => uint256) directorBalanceLastEpoch;

    modifier directorExists {
        require(
            vault.balanceOf(msg.sender) > 0,
            'Boardroom: The director does not exist'
        );
        _;
    }

    modifier onlyVault {
        require(msg.sender == address(vault), 'Boardroom: not vault');

        _;
    }

    event RewardPaid(address indexed user, uint256 reward);
    event RewardAdded(address indexed user, uint256 reward);

    constructor(IERC20 token_, Vault vault_) {
        token = token_;
        vault = vault_;

        BoardSnapshot memory genesisSnapshot =
            BoardSnapshot({
                number: block.number,
                time: 0,
                rewardReceived: 0,
                rewardPerShare: 0
            });
        boardHistory.push(genesisSnapshot);
    }

    function latestSnapshotIndex() public view returns (uint256) {
        return boardHistory.length.sub(1);
    }

    function getDirector(address who)
        external
        view
        override
        returns (Boardseat memory)
    {
        return directors[who];
    }

    function getBoardhistory(uint256 i)
        public
        view
        returns (BoardSnapshot memory)
    {
        return boardHistory[i];
    }

    function getBondingHistory(address who, uint256 epoch)
        public
        view
        returns (BondingSnapshot memory)
    {
        return bondingHistory[who][epoch];
    }

    function getLatestSnapshot() public view returns (BoardSnapshot memory) {
        return boardHistory[latestSnapshotIndex()];
    }

    function getLastSnapshotIndexOf(address director)
        external
        view
        override
        returns (uint256)
    {
        return directors[director].lastSnapshotIndex;
    }

    function getLastSnapshotOf(address director)
        public
        view
        returns (BoardSnapshot memory)
    {
        return boardHistory[directors[director].lastSnapshotIndex];
    }

    function rewardPerShare() public view returns (uint256) {
        return getLatestSnapshot().rewardPerShare;
    }

    function earned(address director) public view virtual returns (uint256) {
        uint256 latestRPS = getLatestSnapshot().rewardPerShare;
        uint256 storedRPS = getLastSnapshotOf(director).rewardPerShare;

        return
            vault
                .balanceWithoutBonded(director)
                .mul(latestRPS.sub(storedRPS))
                .div(1e18)
                .add(directors[director].rewardEarnedCurrEpoch);
    }

    function claimReward() external virtual directorExists returns (uint256) {
        _updateReward(msg.sender);

        uint256 reward = directors[msg.sender].rewardEarnedCurrEpoch;

        if (reward > 0) {
            directors[msg.sender].rewardEarnedCurrEpoch = 0;
            token.transfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }

        return reward;
    }

    function allocateSeigniorage(uint256 amount)
        external
        override
        onlyOneBlock
        onlyOperator
    {
        require(amount > 0, 'Boardroom: Cannot allocate 0');

        uint256 totalSupply = vault.totalBondedSupply();

        // 'Boardroom: Cannot allocate when totalSupply is 0'
        if (totalSupply == 0) return;

        // Create & add new snapshot
        uint256 prevRPS = getLatestSnapshot().rewardPerShare;
        uint256 nextRPS = prevRPS.add(amount.mul(1e18).div(totalSupply));

        BoardSnapshot memory snap =
            BoardSnapshot({
                number: block.number,
                time: block.timestamp,
                rewardReceived: amount,
                rewardPerShare: nextRPS
            });
        boardHistory.push(snap);

        // console.log('allocateSeigniorage totalSupply: %s', totalSupply);
        // console.log('allocateSeigniorage time: %s', block.timestamp);
        // console.log('allocateSeigniorage rewardReceived: %s', amount);
        // console.log('allocateSeigniorage rewardPerShare: %s', nextRPS);

        token.transferFrom(msg.sender, address(this), amount);
        currentEpoch = currentEpoch.add(1);
        emit RewardAdded(msg.sender, amount);
    }

    function updateReward(address director) external virtual onlyVault {
        _updateReward(director);
    }

    function refundReward() external onlyOwner {
        token.transfer(msg.sender, token.balanceOf(address(this)));
    }

    function _updateReward(address director) internal {
        Boardseat memory seat = directors[director];
        seat.rewardEarnedCurrEpoch = earned(director);
        seat.lastSnapshotIndex = latestSnapshotIndex();
        directors[director] = seat;
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/EnumerableSet.sol";
import "../utils/Address.sol";
import "../utils/Context.sol";

/**
 * @dev Contract module that allows children to implement role-based access
 * control mechanisms.
 *
 * Roles are referred to by their `bytes32` identifier. These should be exposed
 * in the external API and be unique. The best way to achieve this is by
 * using `public constant` hash digests:
 *
 * ```
 * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
 * ```
 *
 * Roles can be used to represent a set of permissions. To restrict access to a
 * function call, use {hasRole}:
 *
 * ```
 * function foo() public {
 *     require(hasRole(MY_ROLE, msg.sender));
 *     ...
 * }
 * ```
 *
 * Roles can be granted and revoked dynamically via the {grantRole} and
 * {revokeRole} functions. Each role has an associated admin role, and only
 * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
 *
 * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
 * that only accounts with this role will be able to grant or revoke other
 * roles. More complex role relationships can be created by using
 * {_setRoleAdmin}.
 *
 * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
 * grant and revoke this role. Extra precautions should be taken to secure
 * accounts that have been granted it.
 */
abstract contract AccessControl is Context {
    using EnumerableSet for EnumerableSet.AddressSet;
    using Address for address;

    struct RoleData {
        EnumerableSet.AddressSet members;
        bytes32 adminRole;
    }

    mapping (bytes32 => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /**
     * @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 {_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) public view returns (bool) {
        return _roles[role].members.contains(account);
    }

    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) public view returns (uint256) {
        return _roles[role].members.length();
    }

    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) public view returns (address) {
        return _roles[role].members.at(index);
    }

    /**
     * @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 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.
     */
    function grantRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to grant");

        _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.
     */
    function revokeRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to revoke");

        _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 granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) public virtual {
        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.
     *
     * [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}.
     * ====
     */
    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 {
        emit RoleAdminChanged(role, _roles[role].adminRole, adminRole);
        _roles[role].adminRole = adminRole;
    }

    function _grantRole(bytes32 role, address account) private {
        if (_roles[role].members.add(account)) {
            emit RoleGranted(role, account, _msgSender());
        }
    }

    function _revokeRole(bytes32 role, address account) private {
        if (_roles[role].members.remove(account)) {
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

// File: contracts/owner/Operator.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import '@openzeppelin/contracts/contracts/GSN/Context.sol';
import '@openzeppelin/contracts/contracts/access/Ownable.sol';
import {IOperator} from '../interfaces/IOperator.sol';

abstract contract Operator is Context, Ownable, IOperator {
    address private _operator;

    event OperatorTransferred(
        address indexed previousOperator,
        address indexed newOperator
    );

    constructor() {
        _operator = _msgSender();

        emit OperatorTransferred(address(0), _operator);
    }

    function operator() public view override returns (address) {
        return _operator;
    }

    modifier onlyOperator() {
        require(
            _operator == msg.sender,
            'operator: caller is not the operator'
        );
        _;
    }

    function isOperator() public view override returns (bool) {
        return _msgSender() == _operator;
    }

    function transferOperator(address newOperator_) public override onlyOwner {
        _transferOperator(newOperator_);
    }

    function _transferOperator(address newOperator_) internal {
        require(
            newOperator_ != address(0),
            'operator: zero address given for new operator'
        );

        emit OperatorTransferred(address(0), newOperator_);

        _operator = newOperator_;
    }
}

// File: @openzeppelin/contracts/contracts/math/SafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: contracts/timelock/StakingTimelock.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import {SafeMath} from '@openzeppelin/contracts/contracts/math/SafeMath.sol';
import {Ownable} from '@openzeppelin/contracts/contracts/access/Ownable.sol';

abstract contract StakingTimelock is Ownable {
    using SafeMath for uint256;

    uint256 public duration = 1 days;

    struct StakingDetails {
        uint256 deadline;
        uint256 amount;
        uint256 updatedOn;
    }

    mapping(address => StakingDetails) public stakingDetails;

    constructor(uint256 _duration) {
        duration = _duration;
    }

    modifier checkLockDuration {
        StakingDetails storage _stakerDetails = stakingDetails[msg.sender];

        require(_stakerDetails.deadline != 0);
        require(_stakerDetails.amount != 0);
        require(_stakerDetails.deadline <= block.timestamp);
        _;
    }

    modifier checkLockDurationFor(address who) {
        StakingDetails storage _stakerDetails = stakingDetails[who];

        require(_stakerDetails.deadline != 0);
        require(_stakerDetails.amount != 0);
        require(_stakerDetails.deadline <= block.timestamp);
        _;
    }

    modifier checkLockDurationWithAmount(uint256 amount) {
        StakingDetails storage _stakerDetails = stakingDetails[msg.sender];

        require(_stakerDetails.deadline != 0);
        require(_stakerDetails.amount <= amount);
        require(_stakerDetails.deadline <= block.timestamp);
        _;
    }

    function getStakerDetails(address who)
        public
        view
        returns (
            uint256,
            uint256,
            uint256
        )
    {
        StakingDetails storage _stakerDetails = stakingDetails[who];
        return (
            _stakerDetails.amount,
            _stakerDetails.deadline,
            _stakerDetails.updatedOn
        );
    }

    function getStakedAmount(address who) public view returns (uint256) {
        StakingDetails storage _stakerDetails = stakingDetails[who];
        return _stakerDetails.amount;
    }

    function _updateStakerDetails(address who, uint256 _amount) internal {
        StakingDetails storage _stakerDetails = stakingDetails[who];
        _stakerDetails.deadline = block.timestamp + duration;
        _stakerDetails.updatedOn = block.timestamp;
        _stakerDetails.amount = _amount;
    }

    function changeLockDuration(uint256 _duration) public onlyOwner {
        duration = _duration;
    }

    function getLockDuration() public view returns (uint256) {
        return duration;
    }
}

// File: contracts/interfaces/IVaultBoardroom.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import {IBoardroom} from './IBoardroom.sol';

interface IVaultBoardroom is IBoardroom {
    function updateReward(address who) external;
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;

        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.

            bytes32 lastvalue = set._values[lastIndex];

            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }

    // Bytes32Set

    struct Bytes32Set {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }


    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

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

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

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

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

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

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



// SPDX-License-Identifier: MIT

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 GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/Context.sol";

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

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

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: contracts/interfaces/IOperator.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import {IEpoch} from './IEpoch.sol';

interface IOperator {
    function operator() external view returns (address);

    function isOperator() external view returns (bool);

    function transferOperator(address newOperator_) external;
}

// File: contracts/interfaces/IEpoch.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IEpoch {
    function callable() external view returns (bool);

    function getLastEpoch() external view returns (uint256);

    function getCurrentEpoch() external view returns (uint256);

    function getNextEpoch() external view returns (uint256);

    function nextEpochPoint() external view returns (uint256);

    function getPeriod() external view returns (uint256);

    function getStartTime() external view returns (uint256);

    function setPeriod(uint256 _period) external;
}

// File: contracts/interfaces/IBoardroom.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import {IOperator} from './IOperator.sol';

interface IBoardroom is IOperator {
    struct Boardseat {
        uint256 rewardClaimed;
        uint256 lastRPS;
        uint256 firstRPS;
        uint256 lastBoardSnapshotIndex;
        // // Pending reward from the previous epochs.
        // uint256 rewardPending;
        // Total reward earned in this epoch.
        uint256 rewardEarnedCurrEpoch;
        // Last time reward was claimed(not bound by current epoch).
        uint256 lastClaimedOn;
        // // The reward claimed in vesting period of this epoch.
        // uint256 rewardClaimedCurrEpoch;
        // // Snapshot of boardroom state when last epoch claimed.
        uint256 lastSnapshotIndex;
        // // Rewards claimable now in the current/next claim.
        // uint256 rewardClaimableNow;
        // // keep track of the current rps
        // uint256 claimedRPS;
    }

    struct BoardSnapshot {
        // Block number when recording a snapshot.
        uint256 number;
        // Block timestamp when recording a snapshot.
        uint256 time;
        // Amount of funds received.
        uint256 rewardReceived;
        // Equivalent amount per share staked.
        uint256 rewardPerShare;
    }

    struct BondingSnapshot {
        uint256 epoch;
        // Time when first bonding was made.
        uint256 when;
        // The snapshot index of when first bonded.
        uint256 balance;
        uint256 valid;
    }

    // function updateReward(address director) external;

    function allocateSeigniorage(uint256 amount) external;

    function getDirector(address who) external view returns (Boardseat memory);

    function getLastSnapshotIndexOf(address director)
        external
        view
        returns (uint256);
}

// File: contracts/lib/Safe112.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

library Safe112 {
    function add(uint112 a, uint112 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, 'Safe112: addition overflow');

        return c;
    }

    function sub(uint112 a, uint112 b) internal pure returns (uint256) {
        return sub(a, b, 'Safe112: subtraction overflow');
    }

    function sub(
        uint112 a,
        uint112 b,
        string memory errorMessage
    ) internal pure returns (uint112) {
        require(b <= a, errorMessage);
        uint112 c = a - b;

        return c;
    }

    function mul(uint112 a, uint112 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, 'Safe112: multiplication overflow');

        return c;
    }

    function div(uint112 a, uint112 b) internal pure returns (uint256) {
        return div(a, b, 'Safe112: division by zero');
    }

    function div(
        uint112 a,
        uint112 b,
        string memory errorMessage
    ) internal pure returns (uint112) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint112 c = a / b;

        return c;
    }

    function mod(uint112 a, uint112 b) internal pure returns (uint256) {
        return mod(a, b, 'Safe112: modulo by zero');
    }

    function mod(
        uint112 a,
        uint112 b,
        string memory errorMessage
    ) internal pure returns (uint112) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

// File: contracts/utils/ContractGuard.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

contract ContractGuard {
    mapping(uint256 => mapping(address => bool)) private _status;

    function checkSameOriginReentranted() internal view returns (bool) {
        return _status[block.number][tx.origin];
    }

    function checkSameSenderReentranted() internal view returns (bool) {
        return _status[block.number][msg.sender];
    }

    modifier onlyOneBlock() {
        require(
            !checkSameOriginReentranted(),
            'ContractGuard: one block, one function'
        );
        require(
            !checkSameSenderReentranted(),
            'ContractGuard: one block, one function'
        );

        _;

        _status[block.number][tx.origin] = true;
        _status[block.number][msg.sender] = true;
    }
}

// File: contracts/interfaces/IBasisAsset.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;
import {IERC20} from '@openzeppelin/contracts/contracts/token/ERC20/IERC20.sol';

interface IBasisAsset is IERC20 {
    function mint(address recipient, uint256 amount) external returns (bool);

    function burn(uint256 amount) external;

    function burnFrom(address from, uint256 amount) external;

    function isOperator() external returns (bool);

    function operator() external view returns (address);

    function transferOperator(address newOperator_) external;

    function transferOwnership(address newOwner) external;
}