Contract

// SPDX-License-Identifier: MIT
pragma solidity 0.8.10;


import {MathUpgradeable as Math} from "MathUpgradeable.sol";
import {OwnableUpgradeable as Ownable} from "OwnableUpgradeable.sol";
import {IERC20Upgradeable as IERC20} from "IERC20Upgradeable.sol";
import {PausableUpgradeable as Pausable} from "PausableUpgradeable.sol";
import {SafeERC20Upgradeable as SafeERC20} from "SafeERC20Upgradeable.sol";
import {ReentrancyGuardUpgradeable as ReentrancyGuard} from "ReentrancyGuardUpgradeable.sol";

contract MultiRewards is Ownable, ReentrancyGuard, Pausable {
  using SafeERC20 for IERC20;

  /* ========== STATE VARIABLES ========== */

  struct Reward {
    bool shouldTransfer;
    address rewardsDistributor;
    uint256 rewardsDuration;
    uint256 periodFinish;
    uint256 rewardRate;
    uint256 lastUpdateTime;
    uint256 rewardPerTokenStored;
  }
  IERC20 public stakingToken;
  mapping(address => Reward) public rewardData;
  address[] public rewardTokens;

  // user -> reward token -> amount
  mapping(address => mapping(address => uint256)) public userRewardPerTokenPaid;
  mapping(address => mapping(address => uint256)) public rewards;

  uint256 private _totalSupply;
  mapping(address => uint256) private _balances;

  /* ========== INITIALIZE ========== */

  function initialize(address _owner, address _stakingToken) public initializer {
    stakingToken = IERC20(_stakingToken);

    // Init base contracts.

    __Ownable_init();
    __Pausable_init();
    __ReentrancyGuard_init();

    // Transfer ownership.
    transferOwnership(_owner);
  }

  /* ========== ADD NEW REWARD TOKEN ========== */
  function addReward(
    address _rewardsToken,
    address _rewardsDistributor,
    uint256 _rewardsDuration,
    bool _shouldTransfer // wheter to transfer the rewards from the rewards distributor upon notifyReward call or not
  ) public onlyOwner {
    require(rewardData[_rewardsToken].rewardsDuration == 0);
    rewardTokens.push(_rewardsToken);
    rewardData[_rewardsToken].rewardsDistributor = _rewardsDistributor;
    rewardData[_rewardsToken].rewardsDuration = _rewardsDuration;
    rewardData[_rewardsToken].shouldTransfer = _shouldTransfer;
  }

  /* ========== VIEWS ========== */

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

  function balanceOf(address account) external view returns (uint256) {
    return _balances[account];
  }

  function lastTimeRewardApplicable(address _rewardsToken) public view returns (uint256) {
    return Math.min(block.timestamp, rewardData[_rewardsToken].periodFinish);
  }

  function rewardPerToken(address _rewardsToken) public view returns (uint256) {
    if (_totalSupply == 0) {
      return rewardData[_rewardsToken].rewardPerTokenStored;
    }
    return rewardData[_rewardsToken].rewardPerTokenStored + (
      (lastTimeRewardApplicable(_rewardsToken) - rewardData[_rewardsToken].lastUpdateTime) * rewardData[_rewardsToken].rewardRate * 1e18 / _totalSupply
    );
  }

  function earned(address account, address _rewardsToken) public view returns (uint256) {
    return (_balances[account] * (rewardPerToken(_rewardsToken) - userRewardPerTokenPaid[account][_rewardsToken]) / 1e18 ) + rewards[account][_rewardsToken];
  }

  function getRewardForDuration(address _rewardsToken) external view returns (uint256) {
    return rewardData[_rewardsToken].rewardRate * rewardData[_rewardsToken].rewardsDuration;
  }

  /* ========== MUTATIVE FUNCTIONS ========== */

  function setRewardsDistributor(address _rewardsToken, address _rewardsDistributor) external onlyOwner {
    rewardData[_rewardsToken].rewardsDistributor = _rewardsDistributor;
  }

  function stake(uint256 amount) external nonReentrant whenNotPaused updateReward(msg.sender) {
    require(amount > 0, "Cannot stake 0");
    _totalSupply += amount;
    _balances[msg.sender] += amount;
    stakingToken.safeTransferFrom(msg.sender, address(this), amount);
    emit Staked(msg.sender, amount);
  }

  function withdraw(uint256 amount) public nonReentrant updateReward(msg.sender) {
    require(amount > 0, "Cannot withdraw 0");
    _totalSupply -= amount;
    _balances[msg.sender] -= amount;
    stakingToken.safeTransfer(msg.sender, amount);
    emit Withdrawn(msg.sender, amount);
  }

  function getReward() public nonReentrant updateReward(msg.sender) {
    address[] memory _rewardsTokenArr = rewardTokens;

    for (uint256 i; i < _rewardsTokenArr.length; i++) {
      address _rewardsToken = _rewardsTokenArr[i];
      uint256 reward = rewards[msg.sender][_rewardsToken];
      if (reward > 0) {
        rewards[msg.sender][_rewardsToken] = 0;
        IERC20(_rewardsToken).safeTransfer(msg.sender, reward);
        emit RewardPaid(msg.sender, _rewardsToken, reward);
      }
    }
  }

  function exit() external {
    withdraw(_balances[msg.sender]);
    getReward();
  }

  /* ========== RESTRICTED FUNCTIONS ========== */

  function depositReward(address _rewardsToken, uint256 reward) external updateReward(address(0)) {
    require(rewardData[_rewardsToken].rewardsDistributor == msg.sender);
    if (rewardData[_rewardsToken].shouldTransfer) {
      IERC20(_rewardsToken).safeTransferFrom(msg.sender, address(this), reward);
    }

    if (block.timestamp >= rewardData[_rewardsToken].periodFinish) {
      rewardData[_rewardsToken].rewardRate = reward / rewardData[_rewardsToken].rewardsDuration;
    } else {
      uint256 remaining = rewardData[_rewardsToken].periodFinish - block.timestamp;
      uint256 leftover = remaining * rewardData[_rewardsToken].rewardRate;
      rewardData[_rewardsToken].rewardRate = (reward + leftover) / rewardData[_rewardsToken].rewardsDuration;
    }

    rewardData[_rewardsToken].lastUpdateTime = block.timestamp;
    rewardData[_rewardsToken].periodFinish = block.timestamp + rewardData[_rewardsToken].rewardsDuration;
    emit RewardAdded(reward);
  }

  // Added to support recovering LP Rewards from other systems such as BAL to be distributed to holders
  function recoverERC20(address tokenAddress, uint256 tokenAmount) external onlyOwner {
    require(tokenAddress != address(stakingToken), "Cannot withdraw staking token");
    require(rewardData[tokenAddress].lastUpdateTime == 0, "Cannot withdraw reward token");
    IERC20(tokenAddress).safeTransfer(owner(), tokenAmount);
    emit Recovered(tokenAddress, tokenAmount);
  }

  function setRewardsDuration(address _rewardsToken, uint256 _rewardsDuration) external {
    require(
      block.timestamp > rewardData[_rewardsToken].periodFinish,
      "Reward period still active"
    );
    require(rewardData[_rewardsToken].rewardsDistributor == msg.sender);
    require(_rewardsDuration > 0, "Reward duration must be non-zero");
    rewardData[_rewardsToken].rewardsDuration = _rewardsDuration;
    emit RewardsDurationUpdated(_rewardsToken, rewardData[_rewardsToken].rewardsDuration);
  }

  function setShouldTransferRewards(address _rewardsToken, bool _shouldTransfer) external onlyOwner {
    rewardData[_rewardsToken].shouldTransfer = _shouldTransfer;
  }

  function pause() external onlyOwner {
    _pause();
  }

  function unpause() external onlyOwner {
    _unpause();
  }

  /* ========== MODIFIERS ========== */

  modifier updateReward(address account) {
    address[] memory _rewardsToken = rewardTokens;

    for (uint256 i; i < _rewardsToken.length; i++) {
      address token = _rewardsToken[i];
      rewardData[token].rewardPerTokenStored = rewardPerToken(token);
      rewardData[token].lastUpdateTime = lastTimeRewardApplicable(token);
      if (account != address(0)) {
        rewards[account][token] = earned(account, token);
        userRewardPerTokenPaid[account][token] = rewardData[token].rewardPerTokenStored;
      }
    }
    _;
  }

  /* ========== EVENTS ========== */

  event RewardAdded(uint256 reward);
  event Staked(address indexed user, uint256 amount);
  event Withdrawn(address indexed user, uint256 amount);
  event RewardPaid(address indexed user, address indexed rewardsToken, uint256 reward);
  event RewardsDurationUpdated(address token, uint256 newDuration);
  event Recovered(address token, uint256 amount);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library MathUpgradeable {
    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }

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

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

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

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "ContextUpgradeable.sol";
import "Initializable.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 OwnableUpgradeable is Initializable, ContextUpgradeable {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    function __Ownable_init() internal initializer {
        __Context_init_unchained();
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal initializer {
        _setOwner(_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 {
        _setOwner(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");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
    uint256[49] private __gap;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;
import "Initializable.sol";

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract ContextUpgradeable is Initializable {
    function __Context_init() internal initializer {
        __Context_init_unchained();
    }

    function __Context_init_unchained() internal initializer {
    }
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
    uint256[50] private __gap;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 */
abstract contract Initializable {
    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        require(_initializing || !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20Upgradeable {
    /**
     * @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 ^0.8.0;

import "ContextUpgradeable.sol";
import "Initializable.sol";

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    function __Pausable_init() internal initializer {
        __Context_init_unchained();
        __Pausable_init_unchained();
    }

    function __Pausable_init_unchained() internal initializer {
        _paused = false;
    }

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

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

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

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
    uint256[49] private __gap;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "IERC20Upgradeable.sol";
import "AddressUpgradeable.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 SafeERC20Upgradeable {
    using AddressUpgradeable for address;

    function safeTransfer(
        IERC20Upgradeable token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20Upgradeable 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(
        IERC20Upgradeable token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(
        IERC20Upgradeable token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20Upgradeable token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    /**
     * @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(IERC20Upgradeable token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

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

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

        uint256 size;
        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");

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

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

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

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

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

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

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

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

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;
import "Initializable.sol";

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuardUpgradeable is Initializable {
    // 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;

    function __ReentrancyGuard_init() internal initializer {
        __ReentrancyGuard_init_unchained();
    }

    function __ReentrancyGuard_init_unchained() internal initializer {
        _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;
    }
    uint256[49] private __gap;
}

{
  "evmVersion": "istanbul",
  "optimizer": {
    "enabled": true,
    "runs": 1000
  },
  "libraries": {
    "Multirewards.sol": {}
  },
  "outputSelection": {
    "*": {
      "*": [
        "evm.bytecode",
        "evm.deployedBytecode",
        "devdoc",
        "userdoc",
        "metadata",
        "abi"
      ]
    }
  }
}

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6"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_rewardsToken","type":"address"}],"name":"rewardPerToken","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"}],"name":"rewardTokens","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"","type":"address"},{"internalType":"address","name":"","type":"address"}],"name":"rewards","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_rewardsToken","type":"address"},{"internalType":"address","name":"_rewardsDistributor","type":"address"}],"name":"setRewardsDistributor","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_rewardsToken","type":"address"},{"internalType":"uint256","name":"_rewardsDuration","type":"uint256"}],"name":"setRewardsDuration","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_rewardsToken","type":"address"},{"internalType":"bool","name":"_shouldTransfer","type":"bool"}],"name":"setShouldTransferRewards","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"stake","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"stakingToken","outputs":[{"internalType":"contract IERC20Upgradeable","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"totalSupply","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"unpause","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"","type":"address"},{"internalType":"address","name":"","type":"address"}],"name":"userRewardPerTokenPaid","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"withdraw","outputs":[],"stateMutability":"nonpayable","type":"function"}]