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

pragma solidity ^0.8.0;

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

        uint256 size;
        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 Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

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

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

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

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

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

/// @notice A library for performing overflow-/underflow-safe math,
/// updated with awesomeness from of DappHub (https://github.com/dapphub/ds-math).
library AuraMath {
    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
        c = a + b;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256 c) {
        c = a - b;
    }

    function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
        c = a * b;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return 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);
    }

    function to224(uint256 a) internal pure returns (uint224 c) {
        require(a <= type(uint224).max, "AuraMath: uint224 Overflow");
        c = uint224(a);
    }

    function to128(uint256 a) internal pure returns (uint128 c) {
        require(a <= type(uint128).max, "AuraMath: uint128 Overflow");
        c = uint128(a);
    }

    function to112(uint256 a) internal pure returns (uint112 c) {
        require(a <= type(uint112).max, "AuraMath: uint112 Overflow");
        c = uint112(a);
    }

    function to96(uint256 a) internal pure returns (uint96 c) {
        require(a <= type(uint96).max, "AuraMath: uint96 Overflow");
        c = uint96(a);
    }

    function to32(uint256 a) internal pure returns (uint32 c) {
        require(a <= type(uint32).max, "AuraMath: uint32 Overflow");
        c = uint32(a);
    }
}

/// @notice A library for performing overflow-/underflow-safe addition and subtraction on uint32.
library AuraMath32 {
    function sub(uint32 a, uint32 b) internal pure returns (uint32 c) {
        c = a - b;
    }
}

/// @notice A library for performing overflow-/underflow-safe addition and subtraction on uint112.
library AuraMath112 {
    function add(uint112 a, uint112 b) internal pure returns (uint112 c) {
        c = a + b;
    }

    function sub(uint112 a, uint112 b) internal pure returns (uint112 c) {
        c = a - b;
    }
}

/// @notice A library for performing overflow-/underflow-safe addition and subtraction on uint224.
library AuraMath224 {
    function add(uint224 a, uint224 b) internal pure returns (uint224 c) {
        c = a + b;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

interface ICurveGauge {
    function deposit(uint256) external;

    function balanceOf(address) external view returns (uint256);

    function withdraw(uint256) external;

    function claim_rewards() external;

    function reward_tokens(uint256) external view returns (address); //v2

    function rewarded_token() external view returns (address); //v1

    function lp_token() external view returns (address);
}

interface ICurveVoteEscrow {
    function create_lock(uint256, uint256) external;

    function increase_amount(uint256) external;

    function increase_unlock_time(uint256) external;

    function withdraw() external;

    function smart_wallet_checker() external view returns (address);

    function commit_smart_wallet_checker(address) external;

    function apply_smart_wallet_checker() external;
}

interface IWalletChecker {
    function check(address) external view returns (bool);

    function approveWallet(address) external;

    function dao() external view returns (address);
}

interface IVoting {
    function vote(
        uint256,
        bool,
        bool
    ) external; //voteId, support, executeIfDecided

    function getVote(uint256)
        external
        view
        returns (
            bool,
            bool,
            uint64,
            uint64,
            uint64,
            uint64,
            uint256,
            uint256,
            uint256,
            bytes memory
        );

    function vote_for_gauge_weights(address, uint256) external;
}

interface IMinter {
    function mint(address) external;
}

interface IStaker {
    function deposit(address, address) external returns (bool);

    function withdraw(address) external returns (uint256);

    function withdraw(
        address,
        address,
        uint256
    ) external returns (bool);

    function withdrawAll(address, address) external returns (bool);

    function createLock(uint256, uint256) external returns (bool);

    function increaseAmount(uint256) external returns (bool);

    function increaseTime(uint256) external returns (bool);

    function release() external returns (bool);

    function claimCrv(address) external returns (uint256);

    function claimRewards(address) external returns (bool);

    function claimFees(address, address) external returns (uint256);

    function setStashAccess(address, bool) external returns (bool);

    function vote(
        uint256,
        address,
        bool
    ) external returns (bool);

    function voteGaugeWeight(address, uint256) external returns (bool);

    function balanceOfPool(address) external view returns (uint256);

    function operator() external view returns (address);

    function execute(
        address _to,
        uint256 _value,
        bytes calldata _data
    ) external returns (bool, bytes memory);

    function setVote(bytes32 hash, bool valid) external;

    function migrate(address to) external;
}

interface IRewards {
    function stake(address, uint256) external;

    function stakeFor(address, uint256) external;

    function withdraw(address, uint256) external;

    function exit(address) external;

    function getReward(address) external;

    function queueNewRewards(uint256) external;

    function notifyRewardAmount(uint256) external;

    function addExtraReward(address) external;

    function extraRewardsLength() external view returns (uint256);

    function stakingToken() external view returns (address);

    function rewardToken() external view returns (address);

    function earned(address account) external view returns (uint256);
}

interface IStash {
    function stashRewards() external returns (bool);

    function processStash() external returns (bool);

    function claimRewards() external returns (bool);

    function initialize(
        uint256 _pid,
        address _operator,
        address _staker,
        address _gauge,
        address _rewardFactory
    ) external;
}

interface IFeeDistributor {
    function claimToken(address user, address token) external returns (uint256);

    function claimTokens(address user, address[] calldata tokens) external returns (uint256[] memory);

    function getTokenTimeCursor(address token) external view returns (uint256);
}

interface ITokenMinter {
    function mint(address, uint256) external;

    function burn(address, uint256) external;
}

interface IDeposit {
    function isShutdown() external view returns (bool);

    function balanceOf(address _account) external view returns (uint256);

    function totalSupply() external view returns (uint256);

    function poolInfo(uint256)
        external
        view
        returns (
            address,
            address,
            address,
            address,
            address,
            bool
        );

    function rewardClaimed(
        uint256,
        address,
        uint256
    ) external;

    function withdrawTo(
        uint256,
        uint256,
        address
    ) external;

    function claimRewards(uint256, address) external returns (bool);

    function rewardArbitrator() external returns (address);

    function setGaugeRedirect(uint256 _pid) external returns (bool);

    function owner() external returns (address);

    function deposit(
        uint256 _pid,
        uint256 _amount,
        bool _stake
    ) external returns (bool);
}

interface ICrvDeposit {
    function deposit(uint256, bool) external;

    function lockIncentive() external view returns (uint256);
}

interface IRewardFactory {
    function setAccess(address, bool) external;

    function CreateCrvRewards(
        uint256,
        address,
        address
    ) external returns (address);

    function CreateTokenRewards(
        address,
        address,
        address
    ) external returns (address);

    function activeRewardCount(address) external view returns (uint256);

    function addActiveReward(address, uint256) external returns (bool);

    function removeActiveReward(address, uint256) external returns (bool);
}

interface IStashFactory {
    function CreateStash(
        uint256,
        address,
        address,
        uint256
    ) external returns (address);
}

interface ITokenFactory {
    function CreateDepositToken(address) external returns (address);
}

interface IPools {
    function addPool(
        address _lptoken,
        address _gauge,
        uint256 _stashVersion
    ) external returns (bool);

    function forceAddPool(
        address _lptoken,
        address _gauge,
        uint256 _stashVersion
    ) external returns (bool);

    function shutdownPool(uint256 _pid) external returns (bool);

    function poolInfo(uint256)
        external
        view
        returns (
            address,
            address,
            address,
            address,
            address,
            bool
        );

    function poolLength() external view returns (uint256);

    function gaugeMap(address) external view returns (bool);

    function setPoolManager(address _poolM) external;
}

interface IVestedEscrow {
    function fund(address[] calldata _recipient, uint256[] calldata _amount) external returns (bool);
}

interface IRewardDeposit {
    function addReward(address, uint256) external;
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library MathUtil {
    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

/*
   ____            __   __        __   _
  / __/__ __ ___  / /_ / /  ___  / /_ (_)__ __
 _\ \ / // // _ \/ __// _ \/ -_)/ __// / \ \ /
/___/ \_, //_//_/\__//_//_/\__/ \__//_/ /_\_\
     /___/

* Synthetix: MultiRewardPool.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
*/

import "../convex/Interfaces.sol";
import "../convex/MathUtil.sol";
import "@openzeppelin/contracts-0.8/utils/math/SafeMath.sol";
import "@openzeppelin/contracts-0.8/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts-0.8/utils/Address.sol";
import "@openzeppelin/contracts-0.8/token/ERC20/utils/SafeERC20.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts-0.8/security/ReentrancyGuard.sol";
import {AuraMath, AuraMath32, AuraMath112, AuraMath224} from "../utils/AuraMath.sol";

/**
 * @title   MultiRewardPool
 * @author  Synthetix -> ConvexFinance
 * @notice  Unipool rewards contract that is re-deployed from rFactory for each staking pool.
 * @dev     Same as BaseRewardPool except that the DAO can push multiple rewards.
 */
contract MultiRewardPool is ReentrancyGuard {
    using AuraMath for uint256;
    using AuraMath224 for uint224;
    using AuraMath112 for uint112;
    using AuraMath32 for uint32;
    using SafeERC20 for IERC20;

    /* ==========     STRUCTS     ========== */

    struct RewardData {
        /// Timestamp for current period finish
        uint32 periodFinish;
        /// Last time any user took action
        uint32 lastUpdateTime;
        /// RewardRate for the rest of the period
        uint96 rewardRate;
        /// Ever increasing rewardPerToken rate, based on % of total supply
        uint96 rewardPerTokenStored;
    }
    struct UserData {
        uint128 rewardPerTokenPaid;
        uint128 rewards;
    }
    struct EarnedData {
        address token;
        uint256 amount;
    }

    address[] public rewardTokens;
    IERC20 public immutable stakingToken;
    uint256 public constant duration = 12 days;

    address public immutable operator;
    mapping(address => RewardData) public rewardData;

    mapping(address => uint256) public queuedRewards;
    uint256 public currentRewards = 0;
    mapping(address => uint256) public historicalRewards;
    uint256 public constant newRewardRatio = 830;
    uint256 private _totalSupply;
    mapping(address => uint256) public userRewardPerTokenPaid;
    mapping(address => uint256) public rewards;
    mapping(address => uint256) private _balances;

    mapping(address => bool) public rewardDistributors;

    mapping(address => mapping(address => UserData)) public userData;

    event RewardAdded(address indexed _token, 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
    );

    /**
     * @dev This is called directly from RewardFactory
     * @param stakingToken_  Staking token.
     * @param rewardTokens_  Reward tokens
     */
    constructor(
        address stakingToken_,
        address[] memory rewardTokens_,
        address operator_
    ) {
        stakingToken = IERC20(stakingToken_);
        rewardTokens = rewardTokens_;
        operator = operator_;
    }

    modifier updateReward(address _account) {
        {
            uint256 rewardTokensLength = rewardTokens.length;
            for (uint256 i = 0; i < rewardTokensLength; i = unchkIncr(i)) {
                address token = rewardTokens[i];
                uint256 newRewardPerToken = _rewardPerToken(token);
                rewardData[token].rewardPerTokenStored = newRewardPerToken
                    .to96();
                rewardData[token].lastUpdateTime = _lastTimeRewardApplicable(
                    rewardData[token].periodFinish
                ).to32();
                if (_account != address(0)) {
                    userData[_account][token] = UserData({
                        rewardPerTokenPaid: newRewardPerToken.to128(),
                        rewards: _earned(_account, token).to128()
                    });
                }
            }
        }
        _;
    }

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

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

    // Add a new reward token to be distributed to stakers
    function addReward(address _rewardsToken) external {
        require(msg.sender == operator, "!authorized");
        require(
            rewardData[_rewardsToken].lastUpdateTime == 0,
            "Reward already exists"
        );
        require(
            _rewardsToken != address(stakingToken),
            "Cannot add StakingToken as reward"
        );
        require(rewardTokens.length < 5, "Max rewards length");

        rewardTokens.push(_rewardsToken);
        rewardData[_rewardsToken].lastUpdateTime = uint32(block.timestamp);
        rewardData[_rewardsToken].periodFinish = uint32(block.timestamp);
    }

    /***************************************
                VIEWS - REWARDS
    ****************************************/

    // Address and claimable amount of all reward tokens for the given account
    function claimableRewards(
        address _account
    ) external view returns (EarnedData[] memory userRewards) {
        userRewards = new EarnedData[](rewardTokens.length);

        uint256 userRewardsLength = userRewards.length;
        for (uint256 i = 0; i < userRewardsLength; i = unchkIncr(i)) {
            address token = rewardTokens[i];
            userRewards[i].token = token;
            userRewards[i].amount = _earned(_account, token);
        }
        return userRewards;
    }

    function lastTimeRewardApplicable(
        address _rewardsToken
    ) external view returns (uint256) {
        return
            _lastTimeRewardApplicable(rewardData[_rewardsToken].periodFinish);
    }

    function rewardPerToken(
        address _rewardsToken
    ) external view returns (uint256) {
        return _rewardPerToken(_rewardsToken);
    }

    function _earned(
        address _user,
        address _rewardsToken
    ) internal view returns (uint256) {
        UserData memory data = userData[_user][_rewardsToken];
        return
            _balances[_user]
                .mul(
                    _rewardPerToken(_rewardsToken).sub(data.rewardPerTokenPaid)
                )
                .div(1e18)
                .add(data.rewards);
    }

    function _lastTimeRewardApplicable(
        uint256 _finishTime
    ) internal view returns (uint256) {
        return AuraMath.min(block.timestamp, _finishTime);
    }

    function _rewardPerToken(
        address _rewardsToken
    ) internal view returns (uint256) {
        if (_totalSupply == 0) {
            return rewardData[_rewardsToken].rewardPerTokenStored;
        }
        return
            uint256(rewardData[_rewardsToken].rewardPerTokenStored).add(
                _lastTimeRewardApplicable(
                    rewardData[_rewardsToken].periodFinish
                )
                    .sub(rewardData[_rewardsToken].lastUpdateTime)
                    .mul(rewardData[_rewardsToken].rewardRate)
                    .mul(1e18)
                    .div(_totalSupply)
            );
    }

    function deposit(uint256 _amount) public nonReentrant returns (bool) {
        _processStake(_amount, msg.sender);

        stakingToken.safeTransferFrom(msg.sender, address(this), _amount);
        emit Staked(msg.sender, _amount);

        return true;
    }

    function stakeAll() external returns (bool) {
        uint256 balance = stakingToken.balanceOf(msg.sender);
        deposit(balance);
        return true;
    }

    function depositFor(
        uint256 _amount,
        address _for
    ) public nonReentrant returns (bool) {
        _processStake(_amount, _for);

        //take away from sender
        stakingToken.safeTransferFrom(msg.sender, address(this), _amount);
        emit Staked(_for, _amount);

        return true;
    }

    /**
     * @dev Generic internal staking function that basically does 3 things: update rewards based
     *      on previous balance, trigger also on any child contracts, then update balances.
     * @param _amount    Units to add to the users balance
     * @param _receiver  Address of user who will receive the stake
     */
    function _processStake(
        uint256 _amount,
        address _receiver
    ) internal updateReward(_receiver) {
        require(_amount > 0, "RewardPool : Cannot stake 0");

        _totalSupply = _totalSupply.add(_amount);
        _balances[_receiver] = _balances[_receiver].add(_amount);
    }

    function withdraw(
        uint256 amount,
        bool claim
    ) public nonReentrant updateReward(msg.sender) returns (bool) {
        require(amount > 0, "RewardPool : Cannot withdraw 0");

        _totalSupply = _totalSupply.sub(amount);
        _balances[msg.sender] = _balances[msg.sender].sub(amount);

        stakingToken.safeTransfer(msg.sender, amount);

        if (claim) {
            _getReward(msg.sender, true);
        }

        emit Withdrawn(msg.sender, amount);
        return true;
    }

    function withdrawAll(bool claim) external {
        withdraw(_balances[msg.sender], claim);
    }

    function withdrawAndUnwrap(
        uint256 amount,
        bool claim
    ) public nonReentrant returns (bool) {
        _withdrawAndUnwrapTo(amount, msg.sender, msg.sender);
        //get rewards too
        if (claim) {
            getReward(msg.sender, true);
        }
        return true;
    }

    function _withdrawAndUnwrapTo(
        uint256 amount,
        address from,
        address receiver
    ) internal updateReward(from) returns (bool) {
        _totalSupply = _totalSupply.sub(amount);
        _balances[from] = _balances[from].sub(amount);

        stakingToken.transfer(receiver, amount);
        emit Withdrawn(from, amount);

        return true;
    }

    function withdrawAllAndUnwrap(bool claim) external {
        withdrawAndUnwrap(_balances[msg.sender], claim);
    }

    /**
     * @dev Gives a staker their rewards, with the option of claiming extra rewards
     * @param _account     Account for which to claim
     * @param _claimExtras Get the child rewards too?
     */
    function getReward(
        address _account,
        bool _claimExtras
    ) public nonReentrant updateReward(_account) returns (bool) {
        return _getReward(_account, _claimExtras);
    }

    function _getReward(
        address _account,
        bool _claimExtras
    ) internal updateReward(_account) returns (bool) {
        uint256 rewardTokensLength = rewardTokens.length;
        for (uint256 i = 0; i < rewardTokensLength; i = unchkIncr(i)) {
            address _rewardsToken = rewardTokens[i];
            uint256 reward = userData[_account][_rewardsToken].rewards;
            if (reward > 0) {
                userData[_account][_rewardsToken].rewards = 0;
                IERC20(_rewardsToken).safeTransfer(_account, reward);
                emit RewardPaid(_account, _rewardsToken, reward);
            }
        }

        return true;
    }

    /**
     * @dev Called by a staker to get their allocated rewards
     */
    function getReward() external returns (bool) {
        getReward(msg.sender, true);
        return true;
    }

    // Modify approval for an address to call queueNewRewards
    function approveRewardDistributor(
        address _rewardsToken,
        address _distributor,
        bool _approved
    ) external {
        require(msg.sender == operator, "!authorized");
        rewardDistributors[_distributor] = _approved;
    }

    /***************************************
                REWARD FUNDING
    ****************************************/
    function queueNewRewards(
        address _rewardsToken,
        uint256 _rewards
    ) external nonReentrant {
        require(
            rewardDistributors[msg.sender] || msg.sender == operator,
            "!authorized"
        );
        require(_rewards > 0, "No reward");

        RewardData storage rdata = rewardData[_rewardsToken];

        IERC20(_rewardsToken).safeTransferFrom(
            msg.sender,
            address(this),
            _rewards
        );

        _rewards = _rewards.add(queuedRewards[_rewardsToken]);
        require(_rewards < 1e25, "!rewards");

        if (block.timestamp >= rdata.periodFinish) {
            _notifyReward(_rewardsToken, _rewards);
            queuedRewards[_rewardsToken] = 0;
            return;
        }

        //et = now - (finish-duration)
        uint256 elapsedTime = block.timestamp.sub(
            rdata.periodFinish.sub(duration.to32())
        );
        //current at now: rewardRate * elapsedTime
        uint256 currentAtNow = rdata.rewardRate * elapsedTime;
        uint256 queuedRatio = currentAtNow.mul(1000).div(_rewards);
        if (queuedRatio < newRewardRatio) {
            _notifyReward(_rewardsToken, _rewards);
            queuedRewards[_rewardsToken] = 0;
        } else {
            queuedRewards[_rewardsToken] = _rewards;
        }
    }

    function _notifyReward(
        address _rewardsToken,
        uint256 _reward
    ) internal updateReward(address(0)) {
        RewardData storage rdata = rewardData[_rewardsToken];
        historicalRewards[_rewardsToken] = historicalRewards[_rewardsToken].add(
            _reward
        );

        if (block.timestamp >= rdata.periodFinish) {
            rdata.rewardRate = _reward.div(duration).to96();
        } else {
            uint256 remaining = uint256(rdata.periodFinish).sub(
                block.timestamp
            );
            uint256 leftover = remaining.mul(rdata.rewardRate);
            rdata.rewardRate = _reward.add(leftover).div(duration).to96();
        }

        // Equivalent to 10 million tokens over a weeks duration
        require(rdata.rewardRate < 1e20, "!rewardRate");

        rdata.lastUpdateTime = block.timestamp.to32();
        rdata.periodFinish = block.timestamp.add(duration).to32();

        emit RewardAdded(_rewardsToken, _reward);
    }

    function unchkIncr(uint256 i) private pure returns (uint256) {
        unchecked {
            return i + 1;
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

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

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

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

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

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

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

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

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

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

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

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

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

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

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

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

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

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

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

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

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

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

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

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

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

{
  "compilationTarget": {
    "contracts/core/MultiRewardPool.sol": "MultiRewardPool"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "none"
  },
  "optimizer": {
    "enabled": true,
    "runs": 5000
  },
  "remappings": []
}