pragma solidity ^0.6.0;
//pragma experimental ABIEncoderV2;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
import './lib/Safe112.sol';
import './owner/Operator.sol';
import './utils/ContractGuard.sol';
import './interfaces/IBasisAsset.sol';
contract Boardroom is ContractGuard, Operator {
    using SafeERC20 for IERC20;
    using Address for address;
    using SafeMath for uint256;
    using Safe112 for uint112;
    /* ========== DATA STRUCTURES ========== */
    struct Boardseat {
        uint256 appointmentTime;
        uint256 shares;
    }
    struct BoardSnapshot {
        uint256 timestamp;
        uint256 rewardReceived;
        uint256 totalShares;
    }
    /* ========== STATE VARIABLES ========== */
    IERC20 private cash;
    IERC20 private share;
    mapping(address => Boardseat) private directors;
    BoardSnapshot[] private boardHistory;
    /* ========== CONSTRUCTOR ========== */
    constructor(IERC20 _cash, IERC20 _share) public {
        cash = _cash;
        share = _share;
        BoardSnapshot memory genesisSnapshot = BoardSnapshot(now, 0, 0);
        boardHistory.push(genesisSnapshot);
    }
    /* ========== Modifiers =============== */
    modifier directorExists {
        require(
            directors[msg.sender].shares > 0,
            'Boardroom: The director does not exist'
        );
        _;
    }
    /* ========== VIEW FUNCTIONS ========== */
    function totalShare() public view returns (uint256) {
        return boardHistory[boardHistory.length.sub(1)].totalShares;
    }
    function getShareOf(address director) public view returns (uint256) {
        return directors[director].shares;
    }
    function getAppointmentTimeOf(address director)
        public
        view
        returns (uint256)
    {
        return directors[director].appointmentTime;
    }
    function getCashEarningsOf(address director) public view returns (uint256) {
        uint256 totalRewards = 0;
        if (getShareOf(director) <= 0) {
            return totalRewards;
        }
        for (uint256 i = boardHistory.length; i > 0; i = i.sub(1)) {
            BoardSnapshot memory snapshot = boardHistory[i.sub(1)];
            if (snapshot.timestamp < getAppointmentTimeOf(director)) {
                break;
            }
            uint256 snapshotRewards = snapshot
                .rewardReceived
                .mul(getShareOf(director))
                .div(snapshot.totalShares);
            totalRewards = totalRewards.add(snapshotRewards);
        }
        return totalRewards;
    }
    /* ========== MUTATIVE FUNCTIONS ========== */
    function claimDividends() public onlyOneBlock {
        uint256 totalRewards = getCashEarningsOf(msg.sender);
        directors[msg.sender].appointmentTime = now;
        if (totalRewards > 0) {
            cash.safeTransfer(msg.sender, totalRewards);
            emit RewardPaid(msg.sender, totalRewards);
        }
    }
    function stake(uint256 amount) external {
        require(amount > 0, 'Boardroom: Cannot stake 0');
        // Claim all outstanding dividends before making state changes
        claimDividends();
        // Update director's boardseat
        Boardseat memory director = directors[msg.sender];
        director.shares = director.shares.add(amount);
        directors[msg.sender] = director;
        // Update latest snapshot
        uint256 snapshotIndex = boardHistory.length.sub(1);
        boardHistory[snapshotIndex].totalShares = totalShare().add(amount);
        share.safeTransferFrom(msg.sender, address(this), amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount) public directorExists {
        require(amount > 0, 'Boardroom: Cannot withdraw 0');
        // Claim all outstanding dividends before making state changes
        claimDividends();
        // Update director's boardseat
        uint256 directorShare = getShareOf(msg.sender);
        require(
            directorShare >= amount,
            'Boardroom: withdraw request greater than staked amount'
        );
        directors[msg.sender].shares = directorShare.sub(amount);
        // Update latest snapshot
        uint256 snapshotIndex = boardHistory.length.sub(1);
        boardHistory[snapshotIndex].totalShares = totalShare().sub(amount);
        share.safeTransfer(msg.sender, amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(getShareOf(msg.sender));
    }
    function allocateSeigniorage(uint256 amount)
        external
        onlyOneBlock
        onlyOperator
    {
        require(amount > 0, 'Boardroom: Cannot allocate 0');
        // Create & add new snapshot
        BoardSnapshot memory newSnapshot = BoardSnapshot({
            timestamp: now,
            rewardReceived: amount,
            totalShares: totalShare()
        });
        boardHistory.push(newSnapshot);
        cash.safeTransferFrom(msg.sender, address(this), amount);
        emit RewardAdded(msg.sender, amount);
    }
    /* ========== EVENTS ========== */
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    event RewardAdded(address indexed user, uint256 reward);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
 * @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);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    using Address for address;
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
pragma solidity ^0.6.0;
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;
    }
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/GSN/Context.sol';
import '@openzeppelin/contracts/access/Ownable.sol';
contract Operator is Context, Ownable {
    address private _operator;
    event OperatorTransferred(
        address indexed previousOperator,
        address indexed newOperator
    );
    constructor() internal {
        _operator = _msgSender();
        emit OperatorTransferred(address(0), _operator);
    }
    function operator() public view returns (address) {
        return _operator;
    }
    modifier onlyOperator() {
        require(
            _operator == msg.sender,
            'operator: caller is not the operator'
        );
        _;
    }
    function isOperator() public view returns (bool) {
        return _msgSender() == _operator;
    }
    function transferOperator(address newOperator_) public 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_;
    }
}
pragma solidity ^0.6.12;
contract ContractGuard {
    mapping(uint256 => mapping(address => bool)) private _status;
    modifier onlyOneBlock() {
        require(
            !_status[block.number][tx.origin],
            'ContractGuard: one block, one function'
        );
        _;
        _status[block.number][tx.origin] = true;
    }
}
pragma solidity ^0.6.0;
interface IBasisAsset {
    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);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when 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.
 */
library SafeMath {
    /**
     * @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) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @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 sub(a, b, "SafeMath: subtraction overflow");
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;
        return c;
    }
    /**
     * @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) {
        // 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 0;
        }
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * 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) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }
    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * 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) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts 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 mod(a, b, "SafeMath: modulo by zero");
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.2;
/**
 * @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 in 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");
        return _functionCallWithValue(target, data, value, errorMessage);
    }
    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        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);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/*
 * @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 payable) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "../GSN/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.
 */
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 () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view 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;
    }
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '../Treasury.sol';
import '../Boardroom.sol';
import '../owner/Operator.sol';
contract Tester is Operator {
    Treasury public treasury;
    Boardroom public boardroom;
    constructor(address _treasury, address _boardroom) public {
        treasury = Treasury(_treasury);
        boardroom = Boardroom(_boardroom);
    }
    event OKOnlyOperator(address caller);
    function OnlyOperator() public onlyOperator {
        emit OKOnlyOperator(msg.sender);
    }
    function actionTreasury() public {
        treasury.allocateSeigniorage();
        treasury.allocateSeigniorage(); // should revert
    }
    function actionBoardroom(address share, uint256 amount) public {
        IERC20(share).approve(address(boardroom), amount);
        boardroom.stake(amount);
        boardroom.withdraw(amount); // should revert
    }
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
import '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
import './lib/Babylonian.sol';
import './lib/FixedPoint.sol';
import './lib/Safe112.sol';
import './owner/Operator.sol';
import './utils/ContractGuard.sol';
import './interfaces/IBasisAsset.sol';
import './interfaces/IOracle.sol';
import './interfaces/IBoardroom.sol';
/**
 * @title Basis Cash Treasury contract
 * @notice Monetary policy logic to adjust supplies of basis cash assets
 * @author Summer Smith & Rick Sanchez
 */
contract Treasury is ContractGuard, Operator {
    using FixedPoint for *;
    using SafeERC20 for IERC20;
    using Address for address;
    using SafeMath for uint256;
    using Safe112 for uint112;
    /* ========= CONSTANT VARIABLES ======== */
    uint256 public constant allocationDelay = 1 days;
    /* ========== STATE VARIABLES ========== */
    address private cash;
    address private bond;
    address private share;
    address private boardroom;
    IOracle private cashOracle;
    bool private migrated = false;
    uint256 private seigniorageSaved = 0;
    uint256 public startTime;
    uint256 public cashPriceCeiling;
    uint256 public cashPriceOne;
    uint256 private bondDepletionFloor;
    uint256 private lastAllocated;
    /* ========== CONSTRUCTOR ========== */
    constructor(
        address _cash,
        address _bond,
        address _share,
        address _cashOracle,
        address _boardroom,
        uint256 _startTime
    ) public {
        cash = _cash;
        bond = _bond;
        share = _share;
        cashOracle = IOracle(_cashOracle);
        boardroom = _boardroom;
        startTime = _startTime;
        cashPriceOne = 10**18;
        cashPriceCeiling = uint256(105).mul(cashPriceOne).div(10**2);
        bondDepletionFloor = uint256(1000).mul(cashPriceOne);
        lastAllocated = now;
    }
    /* ========== MODIFIER ========== */
    modifier checkMigration {
        require(!migrated, 'Treasury: this contract has been migrated');
        _;
    }
    modifier checkOperator {
        require(
            IBasisAsset(cash).operator() == address(this),
            'Treasury: this contract is not the operator of the basis cash contract'
        );
        require(
            IBasisAsset(bond).operator() == address(this),
            'Treasury: this contract is not the operator of the basis bond contract'
        );
        require(
            Operator(boardroom).operator() == address(this),
            'Treasury: this contract is not the operator of the boardroom contract'
        );
        _;
    }
    /* ========== VIEW FUNCTIONS ========== */
    function getCashPrice() public view returns (uint256 cashPrice) {
        try cashOracle.consult(cash, 1e18) returns (uint256 price) {
            return price;
        } catch {
            revert('Treasury: failed to consult cash price from the oracle');
        }
    }
    /* ========== GOVERNANCE ========== */
    function migrate(address target) public onlyOperator checkMigration {
        require(block.timestamp >= startTime, 'Treasury: not started yet');
        // cash
        Operator(cash).transferOperator(target);
        Operator(cash).transferOwnership(target);
        IERC20(cash).transfer(target, IERC20(cash).balanceOf(address(this)));
        // bond
        Operator(bond).transferOperator(target);
        Operator(bond).transferOwnership(target);
        IERC20(bond).transfer(target, IERC20(bond).balanceOf(address(this)));
        // share
        Operator(share).transferOperator(target);
        Operator(share).transferOwnership(target);
        IERC20(share).transfer(target, IERC20(share).balanceOf(address(this)));
        migrated = true;
        emit Migration(target);
    }
    /* ========== MUTABLE FUNCTIONS ========== */
    function _getCashPrice() internal returns (uint256 cashPrice) {
        cashPrice = getCashPrice();
        try cashOracle.update()  {} catch {
            revert('Treasury: failed to update cash oracle');
        }
    }
    function _allocateSeigniorage(uint256 cashPrice)
        internal
        onlyOneBlock
        checkOperator
        checkMigration
        returns (bool, string memory)
    {
        if (now.sub(lastAllocated) < allocationDelay) {
            return (false, 'Treasury: a day has not passed yet');
        }
        if (block.timestamp < startTime) {
            return (false, 'Treasury: not started yet');
        }
        if (cashPrice <= cashPriceCeiling) {
            return (false, 'Treasury: there is no seigniorage to be allocated');
        }
        uint256 cashSupply = IERC20(cash).totalSupply();
        uint256 percentage = cashPrice.sub(cashPriceOne);
        uint256 seigniorage = cashSupply.mul(percentage).div(1e18);
        if (seigniorageSaved > bondDepletionFloor) {
            IBasisAsset(cash).mint(address(this), seigniorage);
            IERC20(cash).safeApprove(boardroom, seigniorage);
            IBoardroom(boardroom).allocateSeigniorage(seigniorage);
            emit BoardroomFunded(now, seigniorage);
        } else {
            seigniorageSaved = seigniorageSaved.add(seigniorage);
            IBasisAsset(cash).mint(address(this), seigniorage);
            emit TreasuryFunded(now, seigniorage);
        }
        lastAllocated = now;
        return (true, 'Treasury: success');
    }
    function buyBonds(uint256 amount, uint256 targetPrice) external {
        require(amount > 0, 'Treasury: cannot purchase bonds with zero amount');
        uint256 cashPrice = _getCashPrice();
        require(cashPrice == targetPrice, 'Treasury: cash price moved');
        _allocateSeigniorage(cashPrice); // ignore returns
        uint256 bondPrice = cashPrice;
        IBasisAsset(cash).burnFrom(msg.sender, amount);
        IBasisAsset(bond).mint(msg.sender, amount.mul(1e18).div(bondPrice));
        emit BoughtBonds(msg.sender, amount);
    }
    function redeemBonds(uint256 amount, uint256 targetPrice) external {
        require(amount > 0, 'Treasury: cannot redeem bonds with zero amount');
        uint256 cashPrice = _getCashPrice();
        require(cashPrice == targetPrice, 'Treasury: cash price moved');
        _allocateSeigniorage(cashPrice); // ignore returns
        require(
            cashPrice > cashPriceCeiling,
            'Treasury: bond redemption failed; basis cash remains depegged.'
        );
        uint256 treasuryBalance = IERC20(cash).balanceOf(address(this));
        require(
            treasuryBalance >= amount,
            'Treasury: treasury has no more budget'
        );
        if (seigniorageSaved >= amount) {
            seigniorageSaved = seigniorageSaved.sub(amount);
        } else {
            seigniorageSaved = 0;
        }
        IBasisAsset(bond).burnFrom(msg.sender, amount);
        IERC20(cash).safeTransfer(msg.sender, amount);
        emit RedeemedBonds(msg.sender, amount);
    }
    function allocateSeigniorage() external {
        uint256 cashPrice = _getCashPrice();
        (bool result, string memory reason) = _allocateSeigniorage(cashPrice);
        require(result, reason);
    }
    event Migration(address indexed target);
    event RedeemedBonds(address indexed from, uint256 amount);
    event BoughtBonds(address indexed from, uint256 amount);
    event TreasuryFunded(uint256 timestamp, uint256 seigniorage);
    event BoardroomFunded(uint256 timestamp, uint256 seigniorage);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
 * @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].
 */
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 () internal {
        _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 make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
pragma solidity ^0.6.0;
library Babylonian {
    function sqrt(uint256 y) internal pure returns (uint256 z) {
        if (y > 3) {
            z = y;
            uint256 x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
        // else z = 0
    }
}
pragma solidity ^0.6.0;
import './Babylonian.sol';
// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))
library FixedPoint {
    // range: [0, 2**112 - 1]
    // resolution: 1 / 2**112
    struct uq112x112 {
        uint224 _x;
    }
    // range: [0, 2**144 - 1]
    // resolution: 1 / 2**112
    struct uq144x112 {
        uint256 _x;
    }
    uint8 private constant RESOLUTION = 112;
    uint256 private constant Q112 = uint256(1) << RESOLUTION;
    uint256 private constant Q224 = Q112 << RESOLUTION;
    // encode a uint112 as a UQ112x112
    function encode(uint112 x) internal pure returns (uq112x112 memory) {
        return uq112x112(uint224(x) << RESOLUTION);
    }
    // encodes a uint144 as a UQ144x112
    function encode144(uint144 x) internal pure returns (uq144x112 memory) {
        return uq144x112(uint256(x) << RESOLUTION);
    }
    // divide a UQ112x112 by a uint112, returning a UQ112x112
    function div(uq112x112 memory self, uint112 x)
        internal
        pure
        returns (uq112x112 memory)
    {
        require(x != 0, 'FixedPoint: DIV_BY_ZERO');
        return uq112x112(self._x / uint224(x));
    }
    // multiply a UQ112x112 by a uint, returning a UQ144x112
    // reverts on overflow
    function mul(uq112x112 memory self, uint256 y)
        internal
        pure
        returns (uq144x112 memory)
    {
        uint256 z;
        require(
            y == 0 || (z = uint256(self._x) * y) / y == uint256(self._x),
            'FixedPoint: MULTIPLICATION_OVERFLOW'
        );
        return uq144x112(z);
    }
    // returns a UQ112x112 which represents the ratio of the numerator to the denominator
    // equivalent to encode(numerator).div(denominator)
    function fraction(uint112 numerator, uint112 denominator)
        internal
        pure
        returns (uq112x112 memory)
    {
        require(denominator > 0, 'FixedPoint: DIV_BY_ZERO');
        return uq112x112((uint224(numerator) << RESOLUTION) / denominator);
    }
    // decode a UQ112x112 into a uint112 by truncating after the radix point
    function decode(uq112x112 memory self) internal pure returns (uint112) {
        return uint112(self._x >> RESOLUTION);
    }
    // decode a UQ144x112 into a uint144 by truncating after the radix point
    function decode144(uq144x112 memory self) internal pure returns (uint144) {
        return uint144(self._x >> RESOLUTION);
    }
    // take the reciprocal of a UQ112x112
    function reciprocal(uq112x112 memory self)
        internal
        pure
        returns (uq112x112 memory)
    {
        require(self._x != 0, 'FixedPoint: ZERO_RECIPROCAL');
        return uq112x112(uint224(Q224 / self._x));
    }
    // square root of a UQ112x112
    function sqrt(uq112x112 memory self)
        internal
        pure
        returns (uq112x112 memory)
    {
        return uq112x112(uint224(Babylonian.sqrt(uint256(self._x)) << 56));
    }
}
pragma solidity ^0.6.0;
interface IOracle {
    function update() external;
    function consult(address token, uint256 amountIn)
        external
        view
        returns (uint256 amountOut);
    // function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestamp);
}
pragma solidity ^0.6.0;
interface IBoardroom {
    function allocateSeigniorage(uint256 amount) external;
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/math/SafeMath.sol';
import './lib/Babylonian.sol';
import './lib/FixedPoint.sol';
import './lib/UniswapV2Library.sol';
import './lib/UniswapV2OracleLibrary.sol';
import './interfaces/IUniswapV2Pair.sol';
import './interfaces/IUniswapV2Factory.sol';
// fixed window oracle that recomputes the average price for the entire period once every period
// note that the price average is only guaranteed to be over at least 1 period, but may be over a longer period
contract Oracle {
    using FixedPoint for *;
    uint256 public constant PERIOD = 10 minutes;
    IUniswapV2Pair public pair;
    address public token0;
    address public token1;
    uint256 public price0CumulativeLast;
    uint256 public price1CumulativeLast;
    uint32 public blockTimestampLast;
    FixedPoint.uq112x112 public price0Average;
    FixedPoint.uq112x112 public price1Average;
    constructor(
        address factory,
        address tokenA,
        address tokenB
    ) public {
        IUniswapV2Pair _pair = IUniswapV2Pair(
            UniswapV2Library.pairFor(factory, tokenA, tokenB)
        );
        pair = _pair;
        token0 = _pair.token0();
        token1 = _pair.token1();
        price0CumulativeLast = _pair.price0CumulativeLast(); // fetch the current accumulated price value (1 / 0)
        price1CumulativeLast = _pair.price1CumulativeLast(); // fetch the current accumulated price value (0 / 1)
        uint112 reserve0;
        uint112 reserve1;
        (reserve0, reserve1, blockTimestampLast) = _pair.getReserves();
        require(reserve0 != 0 && reserve1 != 0, 'Oracle: NO_RESERVES'); // ensure that there's liquidity in the pair
    }
    /** @dev Updates 1-day EMA price from Uniswap.  */
    function update() external {
        (
            uint256 price0Cumulative,
            uint256 price1Cumulative,
            uint32 blockTimestamp
        ) = UniswapV2OracleLibrary.currentCumulativePrices(address(pair));
        uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
        if (timeElapsed < PERIOD) {
            // doesn't need to be updated, since a minimum period is not elapsed yet
            return;
        }
        // overflow is desired, casting never truncates
        // cumulative price is in (uq112x112 price * seconds) units so we simply wrap it after division by time elapsed
        price0Average = FixedPoint.uq112x112(
            uint224((price0Cumulative - price0CumulativeLast) / timeElapsed)
        );
        price1Average = FixedPoint.uq112x112(
            uint224((price1Cumulative - price1CumulativeLast) / timeElapsed)
        );
        price0CumulativeLast = price0Cumulative;
        price1CumulativeLast = price1Cumulative;
        blockTimestampLast = blockTimestamp;
        emit Updated(price0Cumulative, price1Cumulative);
    }
    // note this will always return 0 before update has been called successfully for the first time.
    function consult(address token, uint256 amountIn)
        external
        view
        returns (uint144 amountOut)
    {
        if (token == token0) {
            amountOut = price0Average.mul(amountIn).decode144();
        } else {
            require(token == token1, 'Oracle: INVALID_TOKEN');
            amountOut = price1Average.mul(amountIn).decode144();
        }
    }
    function pairFor(
        address factory,
        address tokenA,
        address tokenB
    ) external pure returns (address lpt) {
        return UniswapV2Library.pairFor(factory, tokenA, tokenB);
    }
    event Updated(uint256 price0CumulativeLast, uint256 price1CumulativeLast);
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/math/SafeMath.sol';
import '../interfaces/IUniswapV2Pair.sol';
library UniswapV2Library {
    using SafeMath for uint256;
    // returns sorted token addresses, used to handle return values from pairs sorted in this order
    function sortTokens(address tokenA, address tokenB)
        internal
        pure
        returns (address token0, address token1)
    {
        require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
        (token0, token1) = tokenA < tokenB
            ? (tokenA, tokenB)
            : (tokenB, tokenA);
        require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
    }
    // calculates the CREATE2 address for a pair without making any external calls
    function pairFor(
        address factory,
        address tokenA,
        address tokenB
    ) internal pure returns (address pair) {
        (address token0, address token1) = sortTokens(tokenA, tokenB);
        pair = address(
            uint256(
                keccak256(
                    abi.encodePacked(
                        hex'ff',
                        factory,
                        keccak256(abi.encodePacked(token0, token1)),
                        hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
                    )
                )
            )
        );
    }
    // fetches and sorts the reserves for a pair
    function getReserves(
        address factory,
        address tokenA,
        address tokenB
    ) internal view returns (uint256 reserveA, uint256 reserveB) {
        (address token0, ) = sortTokens(tokenA, tokenB);
        (uint256 reserve0, uint256 reserve1, ) = IUniswapV2Pair(
            pairFor(factory, tokenA, tokenB)
        )
            .getReserves();
        (reserveA, reserveB) = tokenA == token0
            ? (reserve0, reserve1)
            : (reserve1, reserve0);
    }
    // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
    function quote(
        uint256 amountA,
        uint256 reserveA,
        uint256 reserveB
    ) internal pure returns (uint256 amountB) {
        require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT');
        require(
            reserveA > 0 && reserveB > 0,
            'UniswapV2Library: INSUFFICIENT_LIQUIDITY'
        );
        amountB = amountA.mul(reserveB) / reserveA;
    }
    // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
    function getAmountOut(
        uint256 amountIn,
        uint256 reserveIn,
        uint256 reserveOut
    ) internal pure returns (uint256 amountOut) {
        require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT');
        require(
            reserveIn > 0 && reserveOut > 0,
            'UniswapV2Library: INSUFFICIENT_LIQUIDITY'
        );
        uint256 amountInWithFee = amountIn.mul(997);
        uint256 numerator = amountInWithFee.mul(reserveOut);
        uint256 denominator = reserveIn.mul(1000).add(amountInWithFee);
        amountOut = numerator / denominator;
    }
    // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
    function getAmountIn(
        uint256 amountOut,
        uint256 reserveIn,
        uint256 reserveOut
    ) internal pure returns (uint256 amountIn) {
        require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
        require(
            reserveIn > 0 && reserveOut > 0,
            'UniswapV2Library: INSUFFICIENT_LIQUIDITY'
        );
        uint256 numerator = reserveIn.mul(amountOut).mul(1000);
        uint256 denominator = reserveOut.sub(amountOut).mul(997);
        amountIn = (numerator / denominator).add(1);
    }
    // performs chained getAmountOut calculations on any number of pairs
    function getAmountsOut(
        address factory,
        uint256 amountIn,
        address[] memory path
    ) internal view returns (uint256[] memory amounts) {
        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
        amounts = new uint256[](path.length);
        amounts[0] = amountIn;
        for (uint256 i; i < path.length - 1; i++) {
            (uint256 reserveIn, uint256 reserveOut) = getReserves(
                factory,
                path[i],
                path[i + 1]
            );
            amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
        }
    }
    // performs chained getAmountIn calculations on any number of pairs
    function getAmountsIn(
        address factory,
        uint256 amountOut,
        address[] memory path
    ) internal view returns (uint256[] memory amounts) {
        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
        amounts = new uint256[](path.length);
        amounts[amounts.length - 1] = amountOut;
        for (uint256 i = path.length - 1; i > 0; i--) {
            (uint256 reserveIn, uint256 reserveOut) = getReserves(
                factory,
                path[i - 1],
                path[i]
            );
            amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
        }
    }
}
pragma solidity ^0.6.0;
import './FixedPoint.sol';
import '../interfaces/IUniswapV2Pair.sol';
// library with helper methods for oracles that are concerned with computing average prices
library UniswapV2OracleLibrary {
    using FixedPoint for *;
    // helper function that returns the current block timestamp within the range of uint32, i.e. [0, 2**32 - 1]
    function currentBlockTimestamp() internal view returns (uint32) {
        return uint32(block.timestamp % 2**32);
    }
    // produces the cumulative price using counterfactuals to save gas and avoid a call to sync.
    function currentCumulativePrices(address pair)
        internal
        view
        returns (
            uint256 price0Cumulative,
            uint256 price1Cumulative,
            uint32 blockTimestamp
        )
    {
        blockTimestamp = currentBlockTimestamp();
        price0Cumulative = IUniswapV2Pair(pair).price0CumulativeLast();
        price1Cumulative = IUniswapV2Pair(pair).price1CumulativeLast();
        // if time has elapsed since the last update on the pair, mock the accumulated price values
        (
            uint112 reserve0,
            uint112 reserve1,
            uint32 blockTimestampLast
        ) = IUniswapV2Pair(pair).getReserves();
        if (blockTimestampLast != blockTimestamp) {
            // subtraction overflow is desired
            uint32 timeElapsed = blockTimestamp - blockTimestampLast;
            // addition overflow is desired
            // counterfactual
            price0Cumulative +=
                uint256(FixedPoint.fraction(reserve1, reserve0)._x) *
                timeElapsed;
            // counterfactual
            price1Cumulative +=
                uint256(FixedPoint.fraction(reserve0, reserve1)._x) *
                timeElapsed;
        }
    }
}
pragma solidity ^0.6.0;
interface IUniswapV2Pair {
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 value);
    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint256);
    function balanceOf(address owner) external view returns (uint256);
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);
    function approve(address spender, uint256 value) external returns (bool);
    function transfer(address to, uint256 value) external returns (bool);
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);
    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint256);
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
    event Mint(address indexed sender, uint256 amount0, uint256 amount1);
    event Burn(
        address indexed sender,
        uint256 amount0,
        uint256 amount1,
        address indexed to
    );
    event Swap(
        address indexed sender,
        uint256 amount0In,
        uint256 amount1In,
        uint256 amount0Out,
        uint256 amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);
    function MINIMUM_LIQUIDITY() external pure returns (uint256);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves()
        external
        view
        returns (
            uint112 reserve0,
            uint112 reserve1,
            uint32 blockTimestampLast
        );
    function price0CumulativeLast() external view returns (uint256);
    function price1CumulativeLast() external view returns (uint256);
    function kLast() external view returns (uint256);
    function mint(address to) external returns (uint256 liquidity);
    function burn(address to)
        external
        returns (uint256 amount0, uint256 amount1);
    function swap(
        uint256 amount0Out,
        uint256 amount1Out,
        address to,
        bytes calldata data
    ) external;
    function skim(address to) external;
    function sync() external;
    function initialize(address, address) external;
}
pragma solidity ^0.6.0;
interface IUniswapV2Factory {
    event PairCreated(
        address indexed token0,
        address indexed token1,
        address pair,
        uint256
    );
    function getPair(address tokenA, address tokenB)
        external
        view
        returns (address pair);
    function allPairs(uint256) external view returns (address pair);
    function allPairsLength() external view returns (uint256);
    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
}
pragma solidity ^0.6.0;
/*
 * Copyright 2020 Compound Labs, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
import '@openzeppelin/contracts/math/SafeMath.sol';
contract Timelock {
    using SafeMath for uint256;
    event NewAdmin(address indexed newAdmin);
    event NewPendingAdmin(address indexed newPendingAdmin);
    event NewDelay(uint256 indexed newDelay);
    event CancelTransaction(
        bytes32 indexed txHash,
        address indexed target,
        uint256 value,
        string signature,
        bytes data,
        uint256 eta
    );
    event ExecuteTransaction(
        bytes32 indexed txHash,
        address indexed target,
        uint256 value,
        string signature,
        bytes data,
        uint256 eta
    );
    event QueueTransaction(
        bytes32 indexed txHash,
        address indexed target,
        uint256 value,
        string signature,
        bytes data,
        uint256 eta
    );
    uint256 public constant GRACE_PERIOD = 14 days;
    uint256 public constant MINIMUM_DELAY = 2 days;
    uint256 public constant MAXIMUM_DELAY = 30 days;
    address public admin;
    address public pendingAdmin;
    uint256 public delay;
    mapping(bytes32 => bool) public queuedTransactions;
    constructor(address admin_, uint256 delay_) public {
        require(
            delay_ >= MINIMUM_DELAY,
            'Timelock::constructor: Delay must exceed minimum delay.'
        );
        require(
            delay_ <= MAXIMUM_DELAY,
            'Timelock::setDelay: Delay must not exceed maximum delay.'
        );
        admin = admin_;
        delay = delay_;
    }
    receive() external payable {}
    function setDelay(uint256 delay_) public {
        require(
            msg.sender == address(this),
            'Timelock::setDelay: Call must come from Timelock.'
        );
        require(
            delay_ >= MINIMUM_DELAY,
            'Timelock::setDelay: Delay must exceed minimum delay.'
        );
        require(
            delay_ <= MAXIMUM_DELAY,
            'Timelock::setDelay: Delay must not exceed maximum delay.'
        );
        delay = delay_;
        emit NewDelay(delay);
    }
    function acceptAdmin() public {
        require(
            msg.sender == pendingAdmin,
            'Timelock::acceptAdmin: Call must come from pendingAdmin.'
        );
        admin = msg.sender;
        pendingAdmin = address(0);
        emit NewAdmin(admin);
    }
    function setPendingAdmin(address pendingAdmin_) public {
        require(
            msg.sender == address(this),
            'Timelock::setPendingAdmin: Call must come from Timelock.'
        );
        pendingAdmin = pendingAdmin_;
        emit NewPendingAdmin(pendingAdmin);
    }
    function queueTransaction(
        address target,
        uint256 value,
        string memory signature,
        bytes memory data,
        uint256 eta
    ) public returns (bytes32) {
        require(
            msg.sender == admin,
            'Timelock::queueTransaction: Call must come from admin.'
        );
        require(
            eta >= getBlockTimestamp().add(delay),
            'Timelock::queueTransaction: Estimated execution block must satisfy delay.'
        );
        bytes32 txHash = keccak256(
            abi.encode(target, value, signature, data, eta)
        );
        queuedTransactions[txHash] = true;
        emit QueueTransaction(txHash, target, value, signature, data, eta);
        return txHash;
    }
    function cancelTransaction(
        address target,
        uint256 value,
        string memory signature,
        bytes memory data,
        uint256 eta
    ) public {
        require(
            msg.sender == admin,
            'Timelock::cancelTransaction: Call must come from admin.'
        );
        bytes32 txHash = keccak256(
            abi.encode(target, value, signature, data, eta)
        );
        queuedTransactions[txHash] = false;
        emit CancelTransaction(txHash, target, value, signature, data, eta);
    }
    function executeTransaction(
        address target,
        uint256 value,
        string memory signature,
        bytes memory data,
        uint256 eta
    ) public payable returns (bytes memory) {
        require(
            msg.sender == admin,
            'Timelock::executeTransaction: Call must come from admin.'
        );
        bytes32 txHash = keccak256(
            abi.encode(target, value, signature, data, eta)
        );
        require(
            queuedTransactions[txHash],
            "Timelock::executeTransaction: Transaction hasn't been queued."
        );
        require(
            getBlockTimestamp() >= eta,
            "Timelock::executeTransaction: Transaction hasn't surpassed time lock."
        );
        require(
            getBlockTimestamp() <= eta.add(GRACE_PERIOD),
            'Timelock::executeTransaction: Transaction is stale.'
        );
        queuedTransactions[txHash] = false;
        bytes memory callData;
        if (bytes(signature).length == 0) {
            callData = data;
        } else {
            callData = abi.encodePacked(
                bytes4(keccak256(bytes(signature))),
                data
            );
        }
        // solium-disable-next-line security/no-call-value
        (bool success, bytes memory returnData) = target.call{value: value}(
            callData
        );
        require(
            success,
            'Timelock::executeTransaction: Transaction execution reverted.'
        );
        emit ExecuteTransaction(txHash, target, value, signature, data, eta);
        return returnData;
    }
    function getBlockTimestamp() internal view returns (uint256) {
        // solium-disable-next-line security/no-block-members
        return block.timestamp;
    }
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/math/SafeMath.sol';
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '../interfaces/IDistributor.sol';
import '../interfaces/IRewardDistributionRecipient.sol';
contract InitialShareDistributor is IDistributor {
    using SafeMath for uint256;
    event Distributed(address pool, uint256 cashAmount);
    bool public once = true;
    IERC20 public share;
    IRewardDistributionRecipient public daibacLPPool;
    uint256 public daibacInitialBalance;
    IRewardDistributionRecipient public daibasLPPool;
    uint256 public daibasInitialBalance;
    constructor(
        IERC20 _share,
        IRewardDistributionRecipient _daibacLPPool,
        uint256 _daibacInitialBalance,
        IRewardDistributionRecipient _daibasLPPool,
        uint256 _daibasInitialBalance
    ) public {
        share = _share;
        daibacLPPool = _daibacLPPool;
        daibacInitialBalance = _daibacInitialBalance;
        daibasLPPool = _daibasLPPool;
        daibasInitialBalance = _daibasInitialBalance;
    }
    function distribute() public override {
        require(
            once,
            'InitialShareDistributor: you cannot run this function twice'
        );
        share.transfer(address(daibacLPPool), daibacInitialBalance);
        daibacLPPool.notifyRewardAmount(daibacInitialBalance);
        emit Distributed(address(daibacLPPool), daibacInitialBalance);
        share.transfer(address(daibasLPPool), daibasInitialBalance);
        daibasLPPool.notifyRewardAmount(daibasInitialBalance);
        emit Distributed(address(daibasLPPool), daibasInitialBalance);
        once = false;
    }
}
pragma solidity ^0.6.0;
interface IDistributor {
    function distribute() external;
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/access/Ownable.sol';
abstract contract IRewardDistributionRecipient is Ownable {
    address public rewardDistribution;
    function notifyRewardAmount(uint256 reward) external virtual;
    modifier onlyRewardDistribution() {
        require(
            _msgSender() == rewardDistribution,
            'Caller is not reward distribution'
        );
        _;
    }
    function setRewardDistribution(address _rewardDistribution)
        external
        virtual
        onlyOwner
    {
        rewardDistribution = _rewardDistribution;
    }
}
pragma solidity ^0.6.0;
/**
 *Submitted for verification at Etherscan.io on 2020-07-17
 */
/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\\ \\ / // // _ \\/ __// _ \\/ -_)/ __// / \\ \\ /
/___/ \\_, //_//_/\\__//_//_/\\__/ \\__//_/ /_\\_\\
     /___/
* Synthetix: BASISCASHRewards.sol
*
* Docs: https://docs.synthetix.io/
*
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
// File: @openzeppelin/contracts/math/Math.sol
import '@openzeppelin/contracts/math/Math.sol';
// File: @openzeppelin/contracts/math/SafeMath.sol
import '@openzeppelin/contracts/math/SafeMath.sol';
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
// File: @openzeppelin/contracts/utils/Address.sol
import '@openzeppelin/contracts/utils/Address.sol';
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
// File: contracts/IRewardDistributionRecipient.sol
import '../interfaces/IRewardDistributionRecipient.sol';
import '../token/LPTokenWrapper.sol';
contract DAIBASLPTokenSharePool is
    LPTokenWrapper,
    IRewardDistributionRecipient
{
    IERC20 public basisShare;
    uint256 public DURATION = 365 days;
    uint256 public starttime;
    uint256 public periodFinish = 0;
    uint256 public rewardRate = 0;
    uint256 public lastUpdateTime;
    uint256 public rewardPerTokenStored;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    event RewardAdded(uint256 reward);
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    constructor(
        address basisShare_,
        address lptoken_,
        uint256 starttime_
    ) public {
        basisShare = IERC20(basisShare_);
        lpt = IERC20(lptoken_);
        starttime = starttime_;
    }
    modifier checkStart() {
        require(
            block.timestamp >= starttime,
            'DAIBASLPTokenSharePool: not start'
        );
        _;
    }
    modifier updateReward(address account) {
        rewardPerTokenStored = rewardPerToken();
        lastUpdateTime = lastTimeRewardApplicable();
        if (account != address(0)) {
            rewards[account] = earned(account);
            userRewardPerTokenPaid[account] = rewardPerTokenStored;
        }
        _;
    }
    function lastTimeRewardApplicable() public view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }
    function rewardPerToken() public view returns (uint256) {
        if (totalSupply() == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored.add(
                lastTimeRewardApplicable()
                    .sub(lastUpdateTime)
                    .mul(rewardRate)
                    .mul(1e18)
                    .div(totalSupply())
            );
    }
    function earned(address account) public view returns (uint256) {
        return
            balanceOf(account)
                .mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
                .div(1e18)
                .add(rewards[account]);
    }
    // stake visibility is public as overriding LPTokenWrapper's stake() function
    function stake(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'DAIBASLPTokenSharePool: Cannot stake 0');
        super.stake(amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'DAIBASLPTokenSharePool: Cannot withdraw 0');
        super.withdraw(amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(balanceOf(msg.sender));
        getReward();
    }
    function getReward() public updateReward(msg.sender) checkStart {
        uint256 reward = earned(msg.sender);
        if (reward > 0) {
            rewards[msg.sender] = 0;
            basisShare.safeTransfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }
    }
    function notifyRewardAmount(uint256 reward)
        external
        override
        onlyRewardDistribution
        updateReward(address(0))
    {
        if (block.timestamp > starttime) {
            if (block.timestamp >= periodFinish) {
                rewardRate = reward.div(DURATION);
            } else {
                uint256 remaining = periodFinish.sub(block.timestamp);
                uint256 leftover = remaining.mul(rewardRate);
                rewardRate = reward.add(leftover).div(DURATION);
            }
            lastUpdateTime = block.timestamp;
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(reward);
        } else {
            rewardRate = reward.div(DURATION);
            lastUpdateTime = starttime;
            periodFinish = starttime.add(DURATION);
            emit RewardAdded(reward);
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    /**
     * @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, so we distribute
        return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
    }
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/math/SafeMath.sol';
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
contract LPTokenWrapper {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    IERC20 public lpt;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }
    function stake(uint256 amount) public virtual {
        _totalSupply = _totalSupply.add(amount);
        _balances[msg.sender] = _balances[msg.sender].add(amount);
        lpt.safeTransferFrom(msg.sender, address(this), amount);
    }
    function withdraw(uint256 amount) public virtual {
        _totalSupply = _totalSupply.sub(amount);
        _balances[msg.sender] = _balances[msg.sender].sub(amount);
        lpt.safeTransfer(msg.sender, amount);
    }
}
pragma solidity ^0.6.0;
/**
 *Submitted for verification at Etherscan.io on 2020-07-17
 */
/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\\ \\ / // // _ \\/ __// _ \\/ -_)/ __// / \\ \\ /
/___/ \\_, //_//_/\\__//_//_/\\__/ \\__//_/ /_\\_\\
     /___/
* Synthetix: BASISCASHRewards.sol
*
* Docs: https://docs.synthetix.io/
*
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
// File: @openzeppelin/contracts/math/Math.sol
import '@openzeppelin/contracts/math/Math.sol';
// File: @openzeppelin/contracts/math/SafeMath.sol
import '@openzeppelin/contracts/math/SafeMath.sol';
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
// File: @openzeppelin/contracts/utils/Address.sol
import '@openzeppelin/contracts/utils/Address.sol';
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
// File: contracts/IRewardDistributionRecipient.sol
import '../interfaces/IRewardDistributionRecipient.sol';
import '../token/LPTokenWrapper.sol';
contract DAIBACLPTokenSharePool is
    LPTokenWrapper,
    IRewardDistributionRecipient
{
    IERC20 public basisShare;
    uint256 public constant DURATION = 30 days;
    uint256 public initreward = 18479995 * 10**16; // 184,799.95 Shares
    uint256 public starttime; // starttime TBD
    uint256 public periodFinish = 0;
    uint256 public rewardRate = 0;
    uint256 public lastUpdateTime;
    uint256 public rewardPerTokenStored;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    event RewardAdded(uint256 reward);
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    constructor(
        address basisShare_,
        address lptoken_,
        uint256 starttime_
    ) public {
        basisShare = IERC20(basisShare_);
        lpt = IERC20(lptoken_);
        starttime = starttime_;
    }
    modifier updateReward(address account) {
        rewardPerTokenStored = rewardPerToken();
        lastUpdateTime = lastTimeRewardApplicable();
        if (account != address(0)) {
            rewards[account] = earned(account);
            userRewardPerTokenPaid[account] = rewardPerTokenStored;
        }
        _;
    }
    function lastTimeRewardApplicable() public view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }
    function rewardPerToken() public view returns (uint256) {
        if (totalSupply() == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored.add(
                lastTimeRewardApplicable()
                    .sub(lastUpdateTime)
                    .mul(rewardRate)
                    .mul(1e18)
                    .div(totalSupply())
            );
    }
    function earned(address account) public view returns (uint256) {
        return
            balanceOf(account)
                .mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
                .div(1e18)
                .add(rewards[account]);
    }
    // stake visibility is public as overriding LPTokenWrapper's stake() function
    function stake(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkhalve
        checkStart
    {
        require(amount > 0, 'Cannot stake 0');
        super.stake(amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkhalve
        checkStart
    {
        require(amount > 0, 'Cannot withdraw 0');
        super.withdraw(amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(balanceOf(msg.sender));
        getReward();
    }
    function getReward() public updateReward(msg.sender) checkhalve checkStart {
        uint256 reward = earned(msg.sender);
        if (reward > 0) {
            rewards[msg.sender] = 0;
            basisShare.safeTransfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }
    }
    modifier checkhalve() {
        if (block.timestamp >= periodFinish) {
            initreward = initreward.mul(75).div(100);
            rewardRate = initreward.div(DURATION);
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(initreward);
        }
        _;
    }
    modifier checkStart() {
        require(block.timestamp >= starttime, 'not start');
        _;
    }
    function notifyRewardAmount(uint256 reward)
        external
        override
        onlyRewardDistribution
        updateReward(address(0))
    {
        if (block.timestamp > starttime) {
            if (block.timestamp >= periodFinish) {
                rewardRate = reward.div(DURATION);
            } else {
                uint256 remaining = periodFinish.sub(block.timestamp);
                uint256 leftover = remaining.mul(rewardRate);
                rewardRate = reward.add(leftover).div(DURATION);
            }
            lastUpdateTime = block.timestamp;
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(reward);
        } else {
            rewardRate = initreward.div(DURATION);
            lastUpdateTime = starttime;
            periodFinish = starttime.add(DURATION);
            emit RewardAdded(reward);
        }
    }
}
pragma solidity ^0.6.0;
/**
 *Submitted for verification at Etherscan.io on 2020-07-17
 */
/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\\ \\ / // // _ \\/ __// _ \\/ -_)/ __// / \\ \\ /
/___/ \\_, //_//_/\\__//_//_/\\__/ \\__//_/ /_\\_\\
     /___/
* Synthetix: BASISCASHRewards.sol
*
* Docs: https://docs.synthetix.io/
*
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
// File: @openzeppelin/contracts/math/Math.sol
import '@openzeppelin/contracts/math/Math.sol';
// File: @openzeppelin/contracts/math/SafeMath.sol
import '@openzeppelin/contracts/math/SafeMath.sol';
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
// File: @openzeppelin/contracts/utils/Address.sol
import '@openzeppelin/contracts/utils/Address.sol';
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
// File: contracts/IRewardDistributionRecipient.sol
import '../interfaces/IRewardDistributionRecipient.sol';
contract yCRVWrapper {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    IERC20 public ycrv;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;
    function totalSupply() public virtual view returns (uint256) {
        return _totalSupply;
    }
    function balanceOf(address account) public virtual view returns (uint256) {
        return _balances[account];
    }
    function stake(uint256 amount) public virtual {
        _totalSupply = _totalSupply.add(amount);
        _balances[msg.sender] = _balances[msg.sender].add(amount);
        ycrv.safeTransferFrom(msg.sender, address(this), amount);
    }
    function withdraw(uint256 amount) public virtual {
        _totalSupply = _totalSupply.sub(amount);
        _balances[msg.sender] = _balances[msg.sender].sub(amount);
        ycrv.safeTransfer(msg.sender, amount);
    }
}
contract BACyCRVPool is yCRVWrapper, IRewardDistributionRecipient {
    IERC20 public basisCash;
    uint256 public DURATION = 5 days;
    uint256 public starttime;
    uint256 public periodFinish = 0;
    uint256 public rewardRate = 0;
    uint256 public lastUpdateTime;
    uint256 public rewardPerTokenStored;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    mapping(address => uint256) public deposits;
    event RewardAdded(uint256 reward);
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    constructor(
        address basisCash_,
        address ycrv_,
        uint256 starttime_
    ) public {
        basisCash = IERC20(basisCash_);
        ycrv = IERC20(ycrv_);
        starttime = starttime_;
    }
    modifier checkStart() {
        require(block.timestamp >= starttime, 'BACyCRVPool: not start');
        _;
    }
    modifier updateReward(address account) {
        rewardPerTokenStored = rewardPerToken();
        lastUpdateTime = lastTimeRewardApplicable();
        if (account != address(0)) {
            rewards[account] = earned(account);
            userRewardPerTokenPaid[account] = rewardPerTokenStored;
        }
        _;
    }
    function lastTimeRewardApplicable() public view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }
    function rewardPerToken() public view returns (uint256) {
        if (totalSupply() == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored.add(
                lastTimeRewardApplicable()
                    .sub(lastUpdateTime)
                    .mul(rewardRate)
                    .mul(1e18)
                    .div(totalSupply())
            );
    }
    function earned(address account) public view returns (uint256) {
        return
            balanceOf(account)
                .mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
                .div(1e18)
                .add(rewards[account]);
    }
    // stake visibility is public as overriding LPTokenWrapper's stake() function
    function stake(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACyCRVPool: Cannot stake 0');
        uint256 newDeposit = deposits[msg.sender].add(amount);
        require(
            newDeposit <= 20000e18,
            'BACyCRVPool: deposit amount exceeds maximum 20000'
        );
        deposits[msg.sender] = newDeposit;
        super.stake(amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACyCRVPool: Cannot withdraw 0');
        deposits[msg.sender] = deposits[msg.sender].sub(amount);
        super.withdraw(amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(balanceOf(msg.sender));
        getReward();
    }
    function getReward() public updateReward(msg.sender) checkStart {
        uint256 reward = earned(msg.sender);
        if (reward > 0) {
            rewards[msg.sender] = 0;
            basisCash.safeTransfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }
    }
    function notifyRewardAmount(uint256 reward)
        external
        override
        onlyRewardDistribution
        updateReward(address(0))
    {
        if (block.timestamp > starttime) {
            if (block.timestamp >= periodFinish) {
                rewardRate = reward.div(DURATION);
            } else {
                uint256 remaining = periodFinish.sub(block.timestamp);
                uint256 leftover = remaining.mul(rewardRate);
                rewardRate = reward.add(leftover).div(DURATION);
            }
            lastUpdateTime = block.timestamp;
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(reward);
        } else {
            rewardRate = reward.div(DURATION);
            lastUpdateTime = starttime;
            periodFinish = starttime.add(DURATION);
            emit RewardAdded(reward);
        }
    }
}
pragma solidity ^0.6.0;
import '../distribution/BACDAIPool.sol';
import '../distribution/BACSUSDPool.sol';
import '../distribution/BACUSDCPool.sol';
import '../distribution/BACUSDTPool.sol';
import '../distribution/BACyCRVPool.sol';
import '../interfaces/IDistributor.sol';
contract InitialCashDistributor is IDistributor {
    using SafeMath for uint256;
    event Distributed(address pool, uint256 cashAmount);
    bool public once = true;
    IERC20 public cash;
    IRewardDistributionRecipient[] public pools;
    uint256 public totalInitialBalance;
    constructor(
        IERC20 _cash,
        IRewardDistributionRecipient[] memory _pools,
        uint256 _totalInitialBalance
    ) public {
        require(_pools.length != 0, 'a list of BAC pools are required');
        cash = _cash;
        pools = _pools;
        totalInitialBalance = _totalInitialBalance;
    }
    function distribute() public override {
        require(
            once,
            'InitialCashDistributor: you cannot run this function twice'
        );
        for (uint256 i = 0; i < pools.length; i++) {
            uint256 amount = totalInitialBalance.div(pools.length);
            cash.transfer(address(pools[i]), amount);
            pools[i].notifyRewardAmount(amount);
            emit Distributed(address(pools[i]), amount);
        }
        once = false;
    }
}
pragma solidity ^0.6.0;
/**
 *Submitted for verification at Etherscan.io on 2020-07-17
 */
/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\\ \\ / // // _ \\/ __// _ \\/ -_)/ __// / \\ \\ /
/___/ \\_, //_//_/\\__//_//_/\\__/ \\__//_/ /_\\_\\
     /___/
* Synthetix: BASISCASHRewards.sol
*
* Docs: https://docs.synthetix.io/
*
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
// File: @openzeppelin/contracts/math/Math.sol
import '@openzeppelin/contracts/math/Math.sol';
// File: @openzeppelin/contracts/math/SafeMath.sol
import '@openzeppelin/contracts/math/SafeMath.sol';
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
// File: @openzeppelin/contracts/utils/Address.sol
import '@openzeppelin/contracts/utils/Address.sol';
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
// File: contracts/IRewardDistributionRecipient.sol
import '../interfaces/IRewardDistributionRecipient.sol';
contract DAIWrapper {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    IERC20 public dai;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }
    function stake(uint256 amount) public virtual {
        _totalSupply = _totalSupply.add(amount);
        _balances[msg.sender] = _balances[msg.sender].add(amount);
        dai.safeTransferFrom(msg.sender, address(this), amount);
    }
    function withdraw(uint256 amount) public virtual {
        _totalSupply = _totalSupply.sub(amount);
        _balances[msg.sender] = _balances[msg.sender].sub(amount);
        dai.safeTransfer(msg.sender, amount);
    }
}
contract BACDAIPool is DAIWrapper, IRewardDistributionRecipient {
    IERC20 public basisCash;
    uint256 public DURATION = 5 days;
    uint256 public starttime;
    uint256 public periodFinish = 0;
    uint256 public rewardRate = 0;
    uint256 public lastUpdateTime;
    uint256 public rewardPerTokenStored;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    mapping(address => uint256) public deposits;
    event RewardAdded(uint256 reward);
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    constructor(
        address basisCash_,
        address dai_,
        uint256 starttime_
    ) public {
        basisCash = IERC20(basisCash_);
        dai = IERC20(dai_);
        starttime = starttime_;
    }
    modifier checkStart() {
        require(block.timestamp >= starttime, 'BACDAIPool: not start');
        _;
    }
    modifier updateReward(address account) {
        rewardPerTokenStored = rewardPerToken();
        lastUpdateTime = lastTimeRewardApplicable();
        if (account != address(0)) {
            rewards[account] = earned(account);
            userRewardPerTokenPaid[account] = rewardPerTokenStored;
        }
        _;
    }
    function lastTimeRewardApplicable() public view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }
    function rewardPerToken() public view returns (uint256) {
        if (totalSupply() == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored.add(
                lastTimeRewardApplicable()
                    .sub(lastUpdateTime)
                    .mul(rewardRate)
                    .mul(1e18)
                    .div(totalSupply())
            );
    }
    function earned(address account) public view returns (uint256) {
        return
            balanceOf(account)
                .mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
                .div(1e18)
                .add(rewards[account]);
    }
    // stake visibility is public as overriding LPTokenWrapper's stake() function
    function stake(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACDAIPool: Cannot stake 0');
        uint256 newDeposit = deposits[msg.sender].add(amount);
        require(
            newDeposit <= 20000e18,
            'BACDAIPool: deposit amount exceeds maximum 20000'
        );
        deposits[msg.sender] = newDeposit;
        super.stake(amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACDAIPool: Cannot withdraw 0');
        deposits[msg.sender] = deposits[msg.sender].sub(amount);
        super.withdraw(amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(balanceOf(msg.sender));
        getReward();
    }
    function getReward() public updateReward(msg.sender) checkStart {
        uint256 reward = earned(msg.sender);
        if (reward > 0) {
            rewards[msg.sender] = 0;
            basisCash.safeTransfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }
    }
    function notifyRewardAmount(uint256 reward)
        external
        override
        onlyRewardDistribution
        updateReward(address(0))
    {
        if (block.timestamp > starttime) {
            if (block.timestamp >= periodFinish) {
                rewardRate = reward.div(DURATION);
            } else {
                uint256 remaining = periodFinish.sub(block.timestamp);
                uint256 leftover = remaining.mul(rewardRate);
                rewardRate = reward.add(leftover).div(DURATION);
            }
            lastUpdateTime = block.timestamp;
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(reward);
        } else {
            rewardRate = reward.div(DURATION);
            lastUpdateTime = starttime;
            periodFinish = starttime.add(DURATION);
            emit RewardAdded(reward);
        }
    }
}
pragma solidity ^0.6.0;
/**
 *Submitted for verification at Etherscan.io on 2020-07-17
 */
/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\\ \\ / // // _ \\/ __// _ \\/ -_)/ __// / \\ \\ /
/___/ \\_, //_//_/\\__//_//_/\\__/ \\__//_/ /_\\_\\
     /___/
* Synthetix: BASISCASHRewards.sol
*
* Docs: https://docs.synthetix.io/
*
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
// File: @openzeppelin/contracts/math/Math.sol
import '@openzeppelin/contracts/math/Math.sol';
// File: @openzeppelin/contracts/math/SafeMath.sol
import '@openzeppelin/contracts/math/SafeMath.sol';
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
// File: @openzeppelin/contracts/utils/Address.sol
import '@openzeppelin/contracts/utils/Address.sol';
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
// File: contracts/IRewardDistributionRecipient.sol
import '../interfaces/IRewardDistributionRecipient.sol';
contract SUSDWrapper {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    IERC20 public SUSD;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }
    function stake(uint256 amount) public virtual {
        _totalSupply = _totalSupply.add(amount);
        _balances[msg.sender] = _balances[msg.sender].add(amount);
        SUSD.safeTransferFrom(msg.sender, address(this), amount);
    }
    function withdraw(uint256 amount) public virtual {
        _totalSupply = _totalSupply.sub(amount);
        _balances[msg.sender] = _balances[msg.sender].sub(amount);
        SUSD.safeTransfer(msg.sender, amount);
    }
}
contract BACSUSDPool is SUSDWrapper, IRewardDistributionRecipient {
    IERC20 public basisCash;
    uint256 public DURATION = 5 days;
    uint256 public starttime;
    uint256 public periodFinish = 0;
    uint256 public rewardRate = 0;
    uint256 public lastUpdateTime;
    uint256 public rewardPerTokenStored;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    mapping(address => uint256) public deposits;
    event RewardAdded(uint256 reward);
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    constructor(
        address basisCash_,
        address susd_,
        uint256 starttime_
    ) public {
        basisCash = IERC20(basisCash_);
        SUSD = IERC20(susd_);
        starttime = starttime_;
    }
    modifier checkStart() {
        require(block.timestamp >= starttime, 'BACSUSDPool: not start');
        _;
    }
    modifier updateReward(address account) {
        rewardPerTokenStored = rewardPerToken();
        lastUpdateTime = lastTimeRewardApplicable();
        if (account != address(0)) {
            rewards[account] = earned(account);
            userRewardPerTokenPaid[account] = rewardPerTokenStored;
        }
        _;
    }
    function lastTimeRewardApplicable() public view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }
    function rewardPerToken() public view returns (uint256) {
        if (totalSupply() == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored.add(
                lastTimeRewardApplicable()
                    .sub(lastUpdateTime)
                    .mul(rewardRate)
                    .mul(1e18)
                    .div(totalSupply())
            );
    }
    function earned(address account) public view returns (uint256) {
        return
            balanceOf(account)
                .mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
                .div(1e18)
                .add(rewards[account]);
    }
    // stake visibility is public as overriding LPTokenWrapper's stake() function
    function stake(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACSUSDPool: Cannot stake 0');
        uint256 newDeposit = deposits[msg.sender].add(amount);
        require(
            newDeposit <= 20000e18,
            'BACSUSDPool: deposit amount exceeds maximum 20000'
        );
        deposits[msg.sender] = newDeposit;
        super.stake(amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACSUSDPool: Cannot withdraw 0');
        deposits[msg.sender] = deposits[msg.sender].sub(amount);
        super.withdraw(amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(balanceOf(msg.sender));
        getReward();
    }
    function getReward() public updateReward(msg.sender) checkStart {
        uint256 reward = earned(msg.sender);
        if (reward > 0) {
            rewards[msg.sender] = 0;
            basisCash.safeTransfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }
    }
    function notifyRewardAmount(uint256 reward)
        external
        override
        onlyRewardDistribution
        updateReward(address(0))
    {
        if (block.timestamp > starttime) {
            if (block.timestamp >= periodFinish) {
                rewardRate = reward.div(DURATION);
            } else {
                uint256 remaining = periodFinish.sub(block.timestamp);
                uint256 leftover = remaining.mul(rewardRate);
                rewardRate = reward.add(leftover).div(DURATION);
            }
            lastUpdateTime = block.timestamp;
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(reward);
        } else {
            rewardRate = reward.div(DURATION);
            lastUpdateTime = starttime;
            periodFinish = starttime.add(DURATION);
            emit RewardAdded(reward);
        }
    }
}
pragma solidity ^0.6.0;
/**
 *Submitted for verification at Etherscan.io on 2020-07-17
 */
/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\\ \\ / // // _ \\/ __// _ \\/ -_)/ __// / \\ \\ /
/___/ \\_, //_//_/\\__//_//_/\\__/ \\__//_/ /_\\_\\
     /___/
* Synthetix: BASISCASHRewards.sol
*
* Docs: https://docs.synthetix.io/
*
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
// File: @openzeppelin/contracts/math/Math.sol
import '@openzeppelin/contracts/math/Math.sol';
// File: @openzeppelin/contracts/math/SafeMath.sol
import '@openzeppelin/contracts/math/SafeMath.sol';
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
// File: @openzeppelin/contracts/utils/Address.sol
import '@openzeppelin/contracts/utils/Address.sol';
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
// File: contracts/IRewardDistributionRecipient.sol
import '../interfaces/IRewardDistributionRecipient.sol';
contract USDCWrapper {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    IERC20 public usdc;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }
    function stake(uint256 amount) public virtual {
        _totalSupply = _totalSupply.add(amount);
        _balances[msg.sender] = _balances[msg.sender].add(amount);
        usdc.safeTransferFrom(msg.sender, address(this), amount);
    }
    function withdraw(uint256 amount) public virtual {
        _totalSupply = _totalSupply.sub(amount);
        _balances[msg.sender] = _balances[msg.sender].sub(amount);
        usdc.safeTransfer(msg.sender, amount);
    }
}
contract BACUSDCPool is USDCWrapper, IRewardDistributionRecipient {
    IERC20 public basisCash;
    uint256 public DURATION = 5 days;
    uint256 public starttime;
    uint256 public periodFinish = 0;
    uint256 public rewardRate = 0;
    uint256 public lastUpdateTime;
    uint256 public rewardPerTokenStored;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    mapping(address => uint256) public deposits;
    event RewardAdded(uint256 reward);
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    constructor(
        address basisCash_,
        address usdc_,
        uint256 starttime_
    ) public {
        basisCash = IERC20(basisCash_);
        usdc = IERC20(usdc_);
        starttime = starttime_;
    }
    modifier checkStart() {
        require(block.timestamp >= starttime, 'BACUSDCPool: not start');
        _;
    }
    modifier updateReward(address account) {
        rewardPerTokenStored = rewardPerToken();
        lastUpdateTime = lastTimeRewardApplicable();
        if (account != address(0)) {
            rewards[account] = earned(account);
            userRewardPerTokenPaid[account] = rewardPerTokenStored;
        }
        _;
    }
    function lastTimeRewardApplicable() public view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }
    function rewardPerToken() public view returns (uint256) {
        if (totalSupply() == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored.add(
                lastTimeRewardApplicable()
                    .sub(lastUpdateTime)
                    .mul(rewardRate)
                    .mul(1e18)
                    .div(totalSupply())
            );
    }
    function earned(address account) public view returns (uint256) {
        return
            balanceOf(account)
                .mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
                .div(1e18)
                .add(rewards[account]);
    }
    // stake visibility is public as overriding LPTokenWrapper's stake() function
    function stake(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACUSDCPool: Cannot stake 0');
        uint256 newDeposit = deposits[msg.sender].add(amount);
        require(
            newDeposit <= 20000e6,
            'BACUSDCPool: deposit amount exceeds maximum 20000'
        );
        deposits[msg.sender] = newDeposit;
        super.stake(amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACUSDCPool: Cannot withdraw 0');
        deposits[msg.sender] = deposits[msg.sender].sub(amount);
        super.withdraw(amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(balanceOf(msg.sender));
        getReward();
    }
    function getReward() public updateReward(msg.sender) checkStart {
        uint256 reward = earned(msg.sender);
        if (reward > 0) {
            rewards[msg.sender] = 0;
            basisCash.safeTransfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }
    }
    function notifyRewardAmount(uint256 reward)
        external
        override
        onlyRewardDistribution
        updateReward(address(0))
    {
        if (block.timestamp > starttime) {
            if (block.timestamp >= periodFinish) {
                rewardRate = reward.div(DURATION);
            } else {
                uint256 remaining = periodFinish.sub(block.timestamp);
                uint256 leftover = remaining.mul(rewardRate);
                rewardRate = reward.add(leftover).div(DURATION);
            }
            lastUpdateTime = block.timestamp;
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(reward);
        } else {
            rewardRate = reward.div(DURATION);
            lastUpdateTime = starttime;
            periodFinish = starttime.add(DURATION);
            emit RewardAdded(reward);
        }
    }
}
pragma solidity ^0.6.0;
/**
 *Submitted for verification at Etherscan.io on 2020-07-17
 */
/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\\ \\ / // // _ \\/ __// _ \\/ -_)/ __// / \\ \\ /
/___/ \\_, //_//_/\\__//_//_/\\__/ \\__//_/ /_\\_\\
     /___/
* Synthetix: BASISCASHRewards.sol
*
* Docs: https://docs.synthetix.io/
*
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
// File: @openzeppelin/contracts/math/Math.sol
import '@openzeppelin/contracts/math/Math.sol';
// File: @openzeppelin/contracts/math/SafeMath.sol
import '@openzeppelin/contracts/math/SafeMath.sol';
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
// File: @openzeppelin/contracts/utils/Address.sol
import '@openzeppelin/contracts/utils/Address.sol';
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
import '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
// File: contracts/IRewardDistributionRecipient.sol
import '../interfaces/IRewardDistributionRecipient.sol';
contract USDTWrapper {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    IERC20 public usdt;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }
    function stake(uint256 amount) public virtual {
        _totalSupply = _totalSupply.add(amount);
        _balances[msg.sender] = _balances[msg.sender].add(amount);
        usdt.safeTransferFrom(msg.sender, address(this), amount);
    }
    function withdraw(uint256 amount) public virtual {
        _totalSupply = _totalSupply.sub(amount);
        _balances[msg.sender] = _balances[msg.sender].sub(amount);
        usdt.safeTransfer(msg.sender, amount);
    }
}
contract BACUSDTPool is USDTWrapper, IRewardDistributionRecipient {
    IERC20 public basisCash;
    uint256 public DURATION = 5 days;
    uint256 public starttime;
    uint256 public periodFinish = 0;
    uint256 public rewardRate = 0;
    uint256 public lastUpdateTime;
    uint256 public rewardPerTokenStored;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    mapping(address => uint256) public deposits;
    event RewardAdded(uint256 reward);
    event Staked(address indexed user, uint256 amount);
    event Withdrawn(address indexed user, uint256 amount);
    event RewardPaid(address indexed user, uint256 reward);
    constructor(
        address basisCash_,
        address usdt_,
        uint256 starttime_
    ) public {
        basisCash = IERC20(basisCash_);
        usdt = IERC20(usdt_);
        starttime = starttime_;
    }
    modifier checkStart() {
        require(block.timestamp >= starttime, 'BACUSDTPool: not start');
        _;
    }
    modifier updateReward(address account) {
        rewardPerTokenStored = rewardPerToken();
        lastUpdateTime = lastTimeRewardApplicable();
        if (account != address(0)) {
            rewards[account] = earned(account);
            userRewardPerTokenPaid[account] = rewardPerTokenStored;
        }
        _;
    }
    function lastTimeRewardApplicable() public view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }
    function rewardPerToken() public view returns (uint256) {
        if (totalSupply() == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored.add(
                lastTimeRewardApplicable()
                    .sub(lastUpdateTime)
                    .mul(rewardRate)
                    .mul(1e18)
                    .div(totalSupply())
            );
    }
    function earned(address account) public view returns (uint256) {
        return
            balanceOf(account)
                .mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
                .div(1e18)
                .add(rewards[account]);
    }
    // stake visibility is public as overriding LPTokenWrapper's stake() function
    function stake(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACUSDTPool: Cannot stake 0');
        uint256 newDeposit = deposits[msg.sender].add(amount);
        require(
            newDeposit <= 20000e6,
            'BACUSDTPool: deposit amount exceeds maximum 20000'
        );
        deposits[msg.sender] = newDeposit;
        super.stake(amount);
        emit Staked(msg.sender, amount);
    }
    function withdraw(uint256 amount)
        public
        override
        updateReward(msg.sender)
        checkStart
    {
        require(amount > 0, 'BACUSDTPool: Cannot withdraw 0');
        deposits[msg.sender] = deposits[msg.sender].sub(amount);
        super.withdraw(amount);
        emit Withdrawn(msg.sender, amount);
    }
    function exit() external {
        withdraw(balanceOf(msg.sender));
        getReward();
    }
    function getReward() public updateReward(msg.sender) checkStart {
        uint256 reward = earned(msg.sender);
        if (reward > 0) {
            rewards[msg.sender] = 0;
            basisCash.safeTransfer(msg.sender, reward);
            emit RewardPaid(msg.sender, reward);
        }
    }
    function notifyRewardAmount(uint256 reward)
        external
        override
        onlyRewardDistribution
        updateReward(address(0))
    {
        if (block.timestamp > starttime) {
            if (block.timestamp >= periodFinish) {
                rewardRate = reward.div(DURATION);
            } else {
                uint256 remaining = periodFinish.sub(block.timestamp);
                uint256 leftover = remaining.mul(rewardRate);
                rewardRate = reward.add(leftover).div(DURATION);
            }
            lastUpdateTime = block.timestamp;
            periodFinish = block.timestamp.add(DURATION);
            emit RewardAdded(reward);
        } else {
            rewardRate = reward.div(DURATION);
            lastUpdateTime = starttime;
            periodFinish = starttime.add(DURATION);
            emit RewardAdded(reward);
        }
    }
}
pragma solidity ^0.6.0;
import './interfaces/IDistributor.sol';
contract Distributor {
    IDistributor[] public distributors;
    constructor(IDistributor[] memory _distributors) public {
        distributors = _distributors;
    }
    function distribute() public {
        for (uint256 i = 0; i < distributors.length; i++) {
            distributors[i].distribute();
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "../../GSN/Context.sol";
import "./IERC20.sol";
import "../../math/SafeMath.sol";
import "../../utils/Address.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;
    using Address for address;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals;
    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name, string memory symbol) public {
        _name = name;
        _symbol = symbol;
        _decimals = 18;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view returns (uint8) {
        return _decimals;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }
    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(sender, recipient, amount);
        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal {
        _decimals = decimals_;
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "../../GSN/Context.sol";
import "./ERC20.sol";
/**
 * @dev Extension of {ERC20} that allows token holders to destroy both their own
 * tokens and those that they have an allowance for, in a way that can be
 * recognized off-chain (via event analysis).
 */
abstract contract ERC20Burnable is Context, ERC20 {
    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for ``accounts``'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");
        _approve(account, _msgSender(), decreasedAllowance);
        _burn(account, amount);
    }
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/token/ERC20/ERC20Burnable.sol';
import '../owner/Operator.sol';
contract MockDai is ERC20Burnable, Operator {
    /**
     * @notice Constructs the Basis Cash ERC-20 contract.
     */
    constructor() public ERC20('DAI', 'DAI') {
        _mint(msg.sender, 10000 * 10**18);
    }
    /**
     * @notice Operator mints dino cash to a recipient
     * @param recipient_ The address of recipient
     * @param amount_ The amount of dino cash to mint to
     * @return whether the process has been done
     */
    function mint(address recipient_, uint256 amount_)
        public
        onlyOperator
        returns (bool)
    {
        uint256 balanceBefore = balanceOf(recipient_);
        _mint(recipient_, amount_);
        uint256 balanceAfter = balanceOf(recipient_);
        return balanceAfter > balanceBefore;
    }
}
pragma solidity ^0.6.0;
import './owner/Operator.sol';
import '@openzeppelin/contracts/token/ERC20/ERC20Burnable.sol';
contract Share is ERC20Burnable, Operator {
    constructor() public ERC20('BAS', 'BAS') {
        // Mints 1 Basis Share to contract creator for initial Uniswap oracle deployment.
        // Will be burned after oracle deployment
        _mint(msg.sender, 1 * 10**18);
    }
    /**
     * @notice Operator mints basis cash to a recipient
     * @param recipient_ The address of recipient
     * @param amount_ The amount of basis cash to mint to
     */
    function mint(address recipient_, uint256 amount_)
        public
        onlyOperator
        returns (bool)
    {
        uint256 balanceBefore = balanceOf(recipient_);
        _mint(recipient_, amount_);
        uint256 balanceAfter = balanceOf(recipient_);
        return balanceAfter >= balanceBefore;
    }
    function burn(uint256 amount) public override onlyOperator {
        super.burn(amount);
    }
    function burnFrom(address account, uint256 amount)
        public
        override
        onlyOperator
    {
        super.burnFrom(account, amount);
    }
}
pragma solidity ^0.6.0;
import '@openzeppelin/contracts/token/ERC20/ERC20Burnable.sol';
import './owner/Operator.sol';
contract Cash is ERC20Burnable, Operator {
    /**
     * @notice Constructs the Basis Cash ERC-20 contract.
     */
    constructor() public ERC20('BAC', 'BAC') {
        // Mints 1 Basis Cash to contract creator for initial Uniswap oracle deployment.
        // Will be burned after oracle deployment
        _mint(msg.sender, 1 * 10**18);
    }
    //    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual override {
    //        super._beforeTokenTransfer(from, to, amount);
    //        require(
    //            to != operator(),
    //            "basis.cash: operator as a recipient is not allowed"
    //        );
    //    }
    /**
     * @notice Operator mints basis cash to a recipient
     * @param recipient_ The address of recipient
     * @param amount_ The amount of basis cash to mint to
     * @return whether the process has been done
     */
    function mint(address recipient_, uint256 amount_)
        public
        onlyOperator
        returns (bool)
    {
        uint256 balanceBefore = balanceOf(recipient_);
        _mint(recipient_, amount_);
        uint256 balanceAfter = balanceOf(recipient_);
        return balanceAfter > balanceBefore;
    }
    function burn(uint256 amount) public override onlyOperator {
        super.burn(amount);
    }
    function burnFrom(address account, uint256 amount)
        public
        override
        onlyOperator
    {
        super.burnFrom(account, amount);
    }
}
pragma solidity ^0.6.0;
import './owner/Operator.sol';
import '@openzeppelin/contracts/token/ERC20/ERC20Burnable.sol';
contract Bond is ERC20Burnable, Ownable, Operator {
    /**
     * @notice Constructs the Basis Bond ERC-20 contract.
     */
    constructor() public ERC20('BAB', 'BAB') {}
    /**
     * @notice Operator mints basis bonds to a recipient
     * @param recipient_ The address of recipient
     * @param amount_ The amount of basis bonds to mint to
     * @return whether the process has been done
     */
    function mint(address recipient_, uint256 amount_)
        public
        onlyOperator
        returns (bool)
    {
        uint256 balanceBefore = balanceOf(recipient_);
        _mint(recipient_, amount_);
        uint256 balanceAfter = balanceOf(recipient_);
        return balanceAfter > balanceBefore;
    }
    function burn(uint256 amount) public override onlyOperator {
        super.burn(amount);
    }
    function burnFrom(address account, uint256 amount)
        public
        override
        onlyOperator
    {
        super.burnFrom(account, amount);
    }
}
pragma solidity ^0.6.0;
interface IUniswapV2Callee {
    function uniswapV2Call(
        address sender,
        uint256 amount0,
        uint256 amount1,
        bytes calldata data
    ) external;
}
pragma solidity ^0.6.0;
interface IUniswapV2ERC20 {
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 value);
    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint256);
    function balanceOf(address owner) external view returns (uint256);
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);
    function approve(address spender, uint256 value) external returns (bool);
    function transfer(address to, uint256 value) external returns (bool);
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);
    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint256);
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.8.0;
contract Migrations {
    address public owner;
    uint256 public last_completed_migration;
    constructor() public {
        owner = msg.sender;
    }
    modifier restricted() {
        if (msg.sender == owner) _;
    }
    function setCompleted(uint256 completed) public restricted {
        last_completed_migration = completed;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.7.0 <0.8.0;
import {
    ERC20,
    ERC20Burnable
} from '@openzeppelin/contracts/token/ERC20/ERC20Burnable.sol';
import {Operator} from '../access/Operator.sol';
contract ShareV2 is ERC20Burnable, Operator {
    /**
     * @notice Constructs the Basis Cash ERC-20 contract.
     */
    constructor() ERC20('BASv2', 'BASv2') {}
    /**
     * @notice Operator mints basis cash to a recipient
     * @param recipient_ The address of recipient
     * @param amount_ The amount of basis cash to mint to
     */
    function mint(address recipient_, uint256 amount_)
        public
        onlyOperator
        returns (bool)
    {
        uint256 balanceBefore = balanceOf(recipient_);
        _mint(recipient_, amount_);
        uint256 balanceAfter = balanceOf(recipient_);
        return balanceAfter >= balanceBefore;
    }
    function burn(uint256 amount) public override onlyOperator {
        super.burn(amount);
    }
    function burnFrom(address account, uint256 amount)
        public
        override
        onlyOperator
    {
        super.burnFrom(account, amount);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../../utils/Context.sol";
import "./ERC20.sol";
/**
 * @dev Extension of {ERC20} that allows token holders to destroy both their own
 * tokens and those that they have an allowance for, in a way that can be
 * recognized off-chain (via event analysis).
 */
abstract contract ERC20Burnable is Context, ERC20 {
    using SafeMath for uint256;
    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for ``accounts``'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");
        _approve(account, _msgSender(), decreasedAllowance);
        _burn(account, amount);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.7.0 <0.8.0;
import {Context, Ownable} from '@openzeppelin/contracts/access/Ownable.sol';
abstract contract Operator is Context, Ownable {
    address private _operator;
    event OperatorTransferred(
        address indexed previousOperator,
        address indexed newOperator
    );
    constructor() {
        _operator = _msgSender();
        emit OperatorTransferred(address(0), _operator);
    }
    function operator() public view returns (address) {
        return _operator;
    }
    modifier onlyOperator() {
        require(
            _operator == _msgSender(),
            'operator: caller is not the operator'
        );
        _;
    }
    function isOperator() public view returns (bool) {
        return _msgSender() == _operator;
    }
    function transferOperator(address newOperator_) public 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_;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <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 payable) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../../utils/Context.sol";
import "./IERC20.sol";
import "../../math/SafeMath.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals;
    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name_, string memory symbol_) public {
        _name = name_;
        _symbol = symbol_;
        _decimals = 18;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual returns (uint8) {
        return _decimals;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }
    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(sender, recipient, amount);
        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal virtual {
        _decimals = decimals_;
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <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);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when 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.
 */
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) {
        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) {
        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) {
        // 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) {
        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) {
        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) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @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) {
        require(b <= a, "SafeMath: subtraction overflow");
        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) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @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. 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) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        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) {
        require(b > 0, "SafeMath: modulo by zero");
        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) {
        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.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * 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) {
        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) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <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 () internal {
        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;
    }
}