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

import "./interfaces/IFraxFarmERC20.sol";
import "./interfaces/IConvexWrapper.sol";
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';


    
contract GaugeExtraRewardDistributor {
    using SafeERC20 for IERC20;

    address public farm;
    address public wrapper;

    address public constant cvx = address(0x4e3FBD56CD56c3e72c1403e103b45Db9da5B9D2B);
    address public constant crv = address(0xD533a949740bb3306d119CC777fa900bA034cd52);

    event Recovered(address _token, uint256 _amount);
    event Distributed(address _token, uint256 _rate);

    constructor(){}

    function initialize(address _farm, address _wrapper) external {
        require(farm == address(0),"init fail");

        farm = _farm;
        wrapper = _wrapper;
    }

    //owner is farm owner
    modifier onlyOwner() {
        require(msg.sender == IFraxFarmERC20(farm).owner(), "!owner");
        _;
    }

    function recoverERC20(address _tokenAddress, uint256 _tokenAmount) external onlyOwner {
        require(_tokenAddress != crv && _tokenAddress != cvx, "invalid");
        IERC20(_tokenAddress).safeTransfer(IFraxFarmERC20(farm).owner(), _tokenAmount);
        emit Recovered(_tokenAddress, _tokenAmount);
    }

    // Add a new reward token to be distributed to stakers
    function distributeReward(address _farm) external returns(uint256 weeks_elapsed, uint256 reward_tally){
        //only allow farm to call
        require(msg.sender == farm);
        
        //get rewards
        IConvexWrapper(wrapper).getReward(_farm);

        //get last period update from farm and figure out period
        uint256 duration = IFraxFarmERC20(_farm).rewardsDuration();
        uint256 periodLength = ((block.timestamp + duration) / duration * duration) - IFraxFarmERC20(_farm).periodFinish();
        weeks_elapsed = (periodLength/duration);

        //reward tokens on farms are constant so dont need to loop, just distribute crv and cvx
        reward_tally = IERC20(crv).balanceOf(address(this));
        uint256 rewardRate = reward_tally / periodLength;
        if(reward_tally > 0){
            IERC20(crv).transfer(farm, reward_tally);
        }
        //if reward_tally is 0, still need to call so reward rate is set to 0
        IFraxFarmERC20(_farm).setRewardVars(crv, rewardRate, address(0), address(this));
        emit Distributed(crv, rewardRate);

        reward_tally = IERC20(cvx).balanceOf(address(this));
        rewardRate = reward_tally / periodLength;
        if(reward_tally > 0){
            IERC20(cvx).transfer(farm, reward_tally);
        }
        IFraxFarmERC20(_farm).setRewardVars(cvx, rewardRate, address(0), address(0)); //keep distributor 0 since its shared
        emit Distributed(cvx, rewardRate);
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;

interface IFraxFarmERC20 {
    
    struct LockedStake {
        bytes32 kek_id;
        uint256 start_timestamp;
        uint256 liquidity;
        uint256 ending_timestamp;
        uint256 lock_multiplier; // 6 decimals of precision. 1x = 1000000
    }

    function owner() external view returns (address);
    function stakingToken() external view returns (address);
    function fraxPerLPToken() external view returns (uint256);
    function calcCurCombinedWeight(address account) external view
        returns (
            uint256 old_combined_weight,
            uint256 new_vefxs_multiplier,
            uint256 new_combined_weight
        );
    function lockedStakesOf(address account) external view returns (LockedStake[] memory);
    function lockedStakesOfLength(address account) external view returns (uint256);
    function lockAdditional(bytes32 kek_id, uint256 addl_liq) external;
    function lockLonger(bytes32 kek_id, uint256 new_ending_ts) external;
    function stakeLocked(uint256 liquidity, uint256 secs) external returns (bytes32);
    function withdrawLocked(bytes32 kek_id, address destination_address) external returns (uint256);



    function periodFinish() external view returns (uint256);
    function rewardsDuration() external view returns (uint256);
    function getAllRewardTokens() external view returns (address[] memory);
    function earned(address account) external view returns (uint256[] memory new_earned);
    function totalLiquidityLocked() external view returns (uint256);
    function lockedLiquidityOf(address account) external view returns (uint256);
    function totalCombinedWeight() external view returns (uint256);
    function combinedWeightOf(address account) external view returns (uint256);
    function lockMultiplier(uint256 secs) external view returns (uint256);
    function rewardRates(uint256 token_idx) external view returns (uint256 rwd_rate);

    function userStakedFrax(address account) external view returns (uint256);
    function proxyStakedFrax(address proxy_address) external view returns (uint256);
    function maxLPForMaxBoost(address account) external view returns (uint256);
    function minVeFXSForMaxBoost(address account) external view returns (uint256);
    function minVeFXSForMaxBoostProxy(address proxy_address) external view returns (uint256);
    function veFXSMultiplier(address account) external view returns (uint256 vefxs_multiplier);

    function toggleValidVeFXSProxy(address proxy_address) external;
    function proxyToggleStaker(address staker_address) external;
    function stakerSetVeFXSProxy(address proxy_address) external;
    function getReward(address destination_address) external returns (uint256[] memory);
    function vefxs_max_multiplier() external view returns(uint256);
    function vefxs_boost_scale_factor() external view returns(uint256);
    function vefxs_per_frax_for_max_boost() external view returns(uint256);
    function getProxyFor(address addr) external view returns (address);

    function sync() external;
    function setRewardVars(address reward_token_address, uint256 _new_rate, address _gauge_controller_address, address _rewards_distributor_address) external;
    function changeTokenManager(address reward_token_address, address new_manager_address) external;
}

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

interface IConvexWrapper{

   struct EarnedData {
        address token;
        uint256 amount;
    }

  function collateralVault() external view returns(address vault);
  function convexPoolId() external view returns(uint256 _poolId);
  function curveToken() external view returns(address);
  function convexToken() external view returns(address);
  function balanceOf(address _account) external view returns(uint256);
  function totalBalanceOf(address _account) external view returns(uint256);
  function deposit(uint256 _amount, address _to) external;
  function stake(uint256 _amount, address _to) external;
  function withdraw(uint256 _amount) external;
  function withdrawAndUnwrap(uint256 _amount) external;
  function getReward(address _account) external;
  function getReward(address _account, address _forwardTo) external;
  function rewardLength() external view returns(uint256);
  function earned(address _account) external view returns(EarnedData[] memory claimable);
  function setVault(address _vault) external;
  function user_checkpoint(address[2] calldata _accounts) external returns(bool);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

        uint256 size;
        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 ^0.8.0;

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

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);
}

{
  "remappings": [],
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "evmVersion": "london",
  "libraries": {},
  "outputSelection": {
    "*": {
      "*": [
        "evm.bytecode",
        "evm.deployedBytecode",
        "devdoc",
        "userdoc",
        "metadata",
        "abi"
      ]
    }
  }
}

[{"inputs":[],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"_token","type":"address"},{"indexed":false,"internalType":"uint256","name":"_rate","type":"uint256"}],"name":"Distributed","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"_token","type":"address"},{"indexed":false,"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"Recovered","type":"event"},{"inputs":[],"name":"crv","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"cvx","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_farm","type":"address"}],"name":"distributeReward","outputs":[{"internalType":"uint256","name":"weeks_elapsed","type":"uint256"},{"internalType":"uint256","name":"reward_tally","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"farm","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_farm","type":"address"},{"internalType":"address","name":"_wrapper","type":"address"}],"name":"initialize","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_tokenAddress","type":"address"},{"internalType":"uint256","name":"_tokenAmount","type":"uint256"}],"name":"recoverERC20","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"wrapper","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"}]