// File: contracts/sushi/APWRewarder.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;
import "./interfaces/IRewarder.sol";

import "@boringcrypto/boring-solidity/contracts/libraries/BoringERC20.sol";
import "@boringcrypto/boring-solidity/contracts/libraries/BoringMath.sol";
import "@boringcrypto/boring-solidity/contracts/BoringOwnable.sol";

import "./MasterChefV2.sol";

// https://github.com/sushiswap/sushiswap/blob/master/contracts/mocks/ComplexRewarder.sol
contract APWRewarder is IRewarder, BoringOwnable {
    using BoringMath for uint256;
    using BoringMath128 for uint128;
    using BoringERC20 for IERC20;

    address private MASTERCHEF_V2;

    /// @notice Info of each MCV2 user.
    /// `amount` LP token amount the user has provided.
    /// `rewardDebt` The amount of SUSHI entitled to the user.
    struct UserInfo {
        uint256 amount;
        uint256 rewardDebt;
    }

    /// @notice Info of each MCV2 pool.
    /// `allocPoint` The amount of allocation points assigned to the pool.
    /// Also known as the amount of SUSHI to distribute per block.
    struct PoolInfo {
        uint128 accSushiPerShare;
        uint64 lastRewardBlock;
        uint64 allocPoint;
    }

    /// @notice Info of each pool.
    mapping(uint256 => PoolInfo) public poolInfo;

    uint256[] public poolIds;

    /// @notice Info of each user that stakes LP tokens.
    mapping(uint256 => mapping(address => UserInfo)) public userInfo;
    /// @dev Total allocation points. Must be the sum of all allocation points in all pools.
    uint256 totalAllocPoint;

    IERC20 public rewardToken;
    uint256 public tokenPerBlock;
    uint256 private constant ACC_TOKEN_PRECISION = 1e12;

    event TokenPerBlockSet(uint256 tokenPerBlock);
    event RewardClaimed(
        address indexed user,
        uint256 indexed pid,
        uint256 amount,
        address indexed to
    );
    event PoolAdded(uint256 indexed pid, uint256 allocPoint);
    event PoolSet(uint256 indexed pid, uint256 allocPoint);
    event PoolUpdated(
        uint256 indexed pid,
        uint64 lastRewardBlock,
        uint256 lpSupply,
        uint256 accSushiPerShare
    );

    /* Modifiers */

    modifier onlyMCV2 {
        require(msg.sender == MASTERCHEF_V2, "ERR_MCV2");
        _;
    }

    /**
     * @notice APWReward constructor
     * @param _MASTERCHEF_V2 Sushi MasterChefV2 address
     * @dev Requires further setup with setTokenPerBlock(uint256)
     */
    constructor(address _MASTERCHEF_V2, IERC20 _rewardToken) public {
        MASTERCHEF_V2 = _MASTERCHEF_V2;
        rewardToken = _rewardToken;
    }

    /* Sushi IRewarder overrides */

    function onSushiReward(
        uint256 _pid,
        address _user,
        address _to,
        uint256,
        uint256 _lpToken
    ) external override onlyMCV2 {
        PoolInfo memory pool = updatePool(_pid);
        UserInfo storage user = userInfo[_pid][_user];
        uint256 pending;
        if (user.amount > 0) {
            pending = (user.amount.mul(pool.accSushiPerShare) /
                ACC_TOKEN_PRECISION)
                .sub(user.rewardDebt);
            rewardToken.safeTransfer(_to, pending);
        }
        user.amount = _lpToken;
        user.rewardDebt =
            _lpToken.mul(pool.accSushiPerShare) /
            ACC_TOKEN_PRECISION;
        emit RewardClaimed(_user, _pid, pending, _to);
    }

    function pendingTokens(
        uint256 _pid,
        address _user,
        uint256
    )
        external
        view
        override
        returns (IERC20[] memory rewardTokens, uint256[] memory rewardAmounts)
    {
        IERC20[] memory _rewardTokens = new IERC20[](1);
        _rewardTokens[0] = (rewardToken);
        uint256[] memory _rewardAmounts = new uint256[](1);
        _rewardAmounts[0] = pendingToken(_pid, _user);
        return (_rewardTokens, _rewardAmounts);
    }

    /* Public */

    /// @notice Returns the number of MCV2 pools.
    function poolLength() public view returns (uint256 pools) {
        pools = poolIds.length;
    }

    /// @notice View function to see pending Token
    /// @param _pid The index of the pool. See `poolInfo`.
    /// @param _user Address of user.
    /// @return pending SUSHI reward for a given user.
    function pendingToken(uint256 _pid, address _user)
        public
        view
        returns (uint256 pending)
    {
        PoolInfo memory pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_user];
        uint256 accSushiPerShare = pool.accSushiPerShare;
        uint256 lpSupply =
            MasterChefV2(MASTERCHEF_V2).lpToken(_pid).balanceOf(MASTERCHEF_V2);
        if (block.number > pool.lastRewardBlock && lpSupply != 0) {
            uint256 blocks = block.number.sub(pool.lastRewardBlock);
            uint256 sushiReward =
                blocks.mul(tokenPerBlock).mul(pool.allocPoint) /
                    totalAllocPoint;
            accSushiPerShare = accSushiPerShare.add(
                sushiReward.mul(ACC_TOKEN_PRECISION) / lpSupply
            );
        }
        pending = (user.amount.mul(accSushiPerShare) / ACC_TOKEN_PRECISION).sub(
            user.rewardDebt
        );
    }

    /// @notice Update reward variables for all pools. Be careful of gas spending!
    /// @param pids Pool IDs of all to be updated. Make sure to update all active pools.
    function massUpdatePools(uint256[] calldata pids) external {
        uint256 len = pids.length;
        for (uint256 i = 0; i < len; ++i) {
            updatePool(pids[i]);
        }
    }

    /// @notice Update reward variables for all pools registered in the contract.
    function updateAllPools() public {
        uint256 len = poolIds.length;
        for (uint256 i = 0; i < len; ++i) {
            updatePool(poolIds[i]);
        }
    }

    /// @notice Update reward variables of the given pool.
    /// @param pid The index of the pool. See `poolInfo`.
    /// @return pool Returns the pool that was updated.
    function updatePool(uint256 pid) public returns (PoolInfo memory pool) {
        pool = poolInfo[pid];
        require(pool.lastRewardBlock != 0, "ERR_INVALID_POOL");
        if (block.number > pool.lastRewardBlock) {
            uint256 lpSupply =
                MasterChefV2(MASTERCHEF_V2).lpToken(pid).balanceOf(
                    MASTERCHEF_V2
                );
            if (lpSupply > 0) {
                uint256 blocks = block.number.sub(pool.lastRewardBlock);
                uint256 sushiReward =
                    blocks.mul(tokenPerBlock).mul(pool.allocPoint) /
                        totalAllocPoint;
                pool.accSushiPerShare = pool.accSushiPerShare.add(
                    (sushiReward.mul(ACC_TOKEN_PRECISION) / lpSupply).to128()
                );
            }
            pool.lastRewardBlock = block.number.to64();
            poolInfo[pid] = pool;
            emit PoolUpdated(
                pid,
                pool.lastRewardBlock,
                lpSupply,
                pool.accSushiPerShare
            );
        }
    }

    /* Admin control */

    function setTokenPerBlock(uint256 _tokenPerBlock) public onlyOwner {
        updateAllPools();
        tokenPerBlock = _tokenPerBlock;
        emit TokenPerBlockSet(_tokenPerBlock);
    }

    function withdraw(address _token, uint256 _amount) public onlyOwner {
        IERC20(_token).safeTransfer(msg.sender, _amount);
    }

    /// @notice Add a new LP to the pool.  Can only be called by the owner.
    /// DO NOT add the same LP token more than once. Rewards will be messed up if you do.
    /// @param allocPoint AP of the new pool.
    /// @param _pid Pid on MCV2
    function addPool(uint256 allocPoint, uint256 _pid) public onlyOwner {
        require(poolInfo[_pid].lastRewardBlock == 0, "ERR_POOL_EXISTS");
        uint256 lastRewardBlock = block.number;
        totalAllocPoint = totalAllocPoint.add(allocPoint);

        poolInfo[_pid] = PoolInfo({
            allocPoint: allocPoint.to64(),
            lastRewardBlock: lastRewardBlock.to64(),
            accSushiPerShare: 0
        });
        poolIds.push(_pid);
        emit PoolAdded(_pid, allocPoint);
    }

    /// @notice Update the given pool's SUSHI allocation point and `IRewarder` contract. Can only be called by the owner.
    /// @param _pid The index of the pool. See `poolInfo`.
    /// @param _allocPoint New AP of the pool.
    function setPool(uint256 _pid, uint256 _allocPoint) public onlyOwner {
        totalAllocPoint = totalAllocPoint.sub(poolInfo[_pid].allocPoint).add(
            _allocPoint
        );
        poolInfo[_pid].allocPoint = _allocPoint.to64();
        emit PoolSet(_pid, _allocPoint);
    }
}

// File: contracts/sushi/interfaces/IRewarder.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;
import "@boringcrypto/boring-solidity/contracts/libraries/BoringERC20.sol";

interface IRewarder {
    using BoringERC20 for IERC20;

    function onSushiReward(
        uint256 pid,
        address user,
        address recipient,
        uint256 sushiAmount,
        uint256 newLpAmount
    ) external;

    function pendingTokens(
        uint256 pid,
        address user,
        uint256 sushiAmount
    ) external view returns (IERC20[] memory, uint256[] memory);
}

// File: @boringcrypto/boring-solidity/contracts/libraries/BoringERC20.sol



// SPDX-License-Identifier: UNLICENSED
pragma solidity 0.6.12;

import "../interfaces/IERC20.sol";

library BoringERC20 {
    function safeSymbol(IERC20 token) internal view returns(string memory) {
        (bool success, bytes memory data) = address(token).staticcall(abi.encodeWithSelector(0x95d89b41));
        return success && data.length > 0 ? abi.decode(data, (string)) : "???";
    }

    function safeName(IERC20 token) internal view returns(string memory) {
        (bool success, bytes memory data) = address(token).staticcall(abi.encodeWithSelector(0x06fdde03));
        return success && data.length > 0 ? abi.decode(data, (string)) : "???";
    }

    function safeDecimals(IERC20 token) internal view returns (uint8) {
        (bool success, bytes memory data) = address(token).staticcall(abi.encodeWithSelector(0x313ce567));
        return success && data.length == 32 ? abi.decode(data, (uint8)) : 18;
    }

    function safeTransfer(IERC20 token, address to, uint256 amount) internal {
        (bool success, bytes memory data) = address(token).call(abi.encodeWithSelector(0xa9059cbb, to, amount));
        require(success && (data.length == 0 || abi.decode(data, (bool))), "BoringERC20: Transfer failed");
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 amount) internal {
        (bool success, bytes memory data) = address(token).call(abi.encodeWithSelector(0x23b872dd, from, to, amount));
        require(success && (data.length == 0 || abi.decode(data, (bool))), "BoringERC20: TransferFrom failed");
    }
}
// File: @boringcrypto/boring-solidity/contracts/libraries/BoringMath.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.6.12;
// a library for performing overflow-safe math, updated with awesomeness from of DappHub (https://github.com/dapphub/ds-math)
library BoringMath {
    function add(uint256 a, uint256 b) internal pure returns (uint256 c) {require((c = a + b) >= b, "BoringMath: Add Overflow");}
    function sub(uint256 a, uint256 b) internal pure returns (uint256 c) {require((c = a - b) <= a, "BoringMath: Underflow");}
    function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {require(b == 0 || (c = a * b)/b == a, "BoringMath: Mul Overflow");}
    function to128(uint256 a) internal pure returns (uint128 c) {
        require(a <= uint128(-1), "BoringMath: uint128 Overflow");
        c = uint128(a);
    }
    function to64(uint256 a) internal pure returns (uint64 c) {
        require(a <= uint64(-1), "BoringMath: uint64 Overflow");
        c = uint64(a);
    }
    function to32(uint256 a) internal pure returns (uint32 c) {
        require(a <= uint32(-1), "BoringMath: uint32 Overflow");
        c = uint32(a);
    }
}

library BoringMath128 {
    function add(uint128 a, uint128 b) internal pure returns (uint128 c) {require((c = a + b) >= b, "BoringMath: Add Overflow");}
    function sub(uint128 a, uint128 b) internal pure returns (uint128 c) {require((c = a - b) <= a, "BoringMath: Underflow");}
}

library BoringMath64 {
    function add(uint64 a, uint64 b) internal pure returns (uint64 c) {require((c = a + b) >= b, "BoringMath: Add Overflow");}
    function sub(uint64 a, uint64 b) internal pure returns (uint64 c) {require((c = a - b) <= a, "BoringMath: Underflow");}
}

library BoringMath32 {
    function add(uint32 a, uint32 b) internal pure returns (uint32 c) {require((c = a + b) >= b, "BoringMath: Add Overflow");}
    function sub(uint32 a, uint32 b) internal pure returns (uint32 c) {require((c = a - b) <= a, "BoringMath: Underflow");}
}
// File: @boringcrypto/boring-solidity/contracts/BoringOwnable.sol



// SPDX-License-Identifier: MIT
// Audit on 5-Jan-2021 by Keno and BoringCrypto

// P1 - P3: OK
pragma solidity 0.6.12;

// Source: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/access/Ownable.sol + Claimable.sol
// Edited by BoringCrypto

// T1 - T4: OK
contract BoringOwnableData {
    // V1 - V5: OK
    address public owner;
    // V1 - V5: OK
    address public pendingOwner;
}

// T1 - T4: OK
contract BoringOwnable is BoringOwnableData {
    // E1: OK
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    constructor () public {
        owner = msg.sender;
        emit OwnershipTransferred(address(0), msg.sender);
    }

    // F1 - F9: OK
    // C1 - C21: OK
    function transferOwnership(address newOwner, bool direct, bool renounce) public onlyOwner {
        if (direct) {
            // Checks
            require(newOwner != address(0) || renounce, "Ownable: zero address");

            // Effects
            emit OwnershipTransferred(owner, newOwner);
            owner = newOwner;
            pendingOwner = address(0);
        } else {
            // Effects
            pendingOwner = newOwner;
        }
    }

    // F1 - F9: OK
    // C1 - C21: OK
    function claimOwnership() public {
        address _pendingOwner = pendingOwner;
        
        // Checks
        require(msg.sender == _pendingOwner, "Ownable: caller != pending owner");

        // Effects
        emit OwnershipTransferred(owner, _pendingOwner);
        owner = _pendingOwner;
        pendingOwner = address(0);
    }

    // M1 - M5: OK
    // C1 - C21: OK
    modifier onlyOwner() {
        require(msg.sender == owner, "Ownable: caller is not the owner");
        _;
    }
}
// File: contracts/sushi/MasterChefV2.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import "@boringcrypto/boring-solidity/contracts/libraries/BoringMath.sol";
import "@boringcrypto/boring-solidity/contracts/BoringBatchable.sol";
import "@boringcrypto/boring-solidity/contracts/BoringOwnable.sol";
import "./libraries/SignedSafeMath.sol";
import "./interfaces/IRewarder.sol";
import "./interfaces/IMasterChef.sol";

interface IMigratorChef {
    // Take the current LP token address and return the new LP token address.
    // Migrator should have full access to the caller's LP token.
    function migrate(IERC20 token) external returns (IERC20);
}

/// @notice The (older) MasterChef contract gives out a constant number of SUSHI tokens per block.
/// It is the only address with minting rights for SUSHI.
/// The idea for this MasterChef V2 (MCV2) contract is therefore to be the owner of a dummy token
/// that is deposited into the MasterChef V1 (MCV1) contract.
/// The allocation point for this pool on MCV1 is the total allocation point for all pools that receive double incentives.
contract MasterChefV2 is BoringOwnable, BoringBatchable {
    using BoringMath for uint256;
    using BoringMath128 for uint128;
    using BoringERC20 for IERC20;
    using SignedSafeMath for int256;

    /// @notice Info of each MCV2 user.
    /// `amount` LP token amount the user has provided.
    /// `rewardDebt` The amount of SUSHI entitled to the user.
    struct UserInfo {
        uint256 amount;
        int256 rewardDebt;
    }

    /// @notice Info of each MCV2 pool.
    /// `allocPoint` The amount of allocation points assigned to the pool.
    /// Also known as the amount of SUSHI to distribute per block.
    struct PoolInfo {
        uint128 accSushiPerShare;
        uint64 lastRewardBlock;
        uint64 allocPoint;
    }

    /// @notice Address of MCV1 contract.
    IMasterChef public immutable MASTER_CHEF;
    /// @notice Address of SUSHI contract.
    IERC20 public immutable SUSHI;
    /// @notice The index of MCV2 master pool in MCV1.
    uint256 public immutable MASTER_PID;
    // @notice The migrator contract. It has a lot of power. Can only be set through governance (owner).
    IMigratorChef public migrator;

    /// @notice Info of each MCV2 pool.
    PoolInfo[] public poolInfo;
    /// @notice Address of the LP token for each MCV2 pool.
    IERC20[] public lpToken;
    /// @notice Address of each `IRewarder` contract in MCV2.
    IRewarder[] public rewarder;

    /// @notice Info of each user that stakes LP tokens.
    mapping(uint256 => mapping(address => UserInfo)) public userInfo;
    /// @dev Total allocation points. Must be the sum of all allocation points in all pools.
    uint256 public totalAllocPoint;

    uint256 private constant MASTERCHEF_SUSHI_PER_BLOCK = 1e20;
    uint256 private constant ACC_SUSHI_PRECISION = 1e12;

    event Deposit(
        address indexed user,
        uint256 indexed pid,
        uint256 amount,
        address indexed to
    );
    event Withdraw(
        address indexed user,
        uint256 indexed pid,
        uint256 amount,
        address indexed to
    );
    event EmergencyWithdraw(
        address indexed user,
        uint256 indexed pid,
        uint256 amount,
        address indexed to
    );
    event Harvest(address indexed user, uint256 indexed pid, uint256 amount);
    event LogPoolAddition(
        uint256 indexed pid,
        uint256 allocPoint,
        IERC20 indexed lpToken,
        IRewarder indexed rewarder
    );
    event LogSetPool(
        uint256 indexed pid,
        uint256 allocPoint,
        IRewarder indexed rewarder,
        bool overwrite
    );
    event LogUpdatePool(
        uint256 indexed pid,
        uint64 lastRewardBlock,
        uint256 lpSupply,
        uint256 accSushiPerShare
    );
    event LogInit();

    /// @param _MASTER_CHEF The SushiSwap MCV1 contract address.
    /// @param _sushi The SUSHI token contract address.
    /// @param _MASTER_PID The pool ID of the dummy token on the base MCV1 contract.
    constructor(
        IMasterChef _MASTER_CHEF,
        IERC20 _sushi,
        uint256 _MASTER_PID
    ) public {
        MASTER_CHEF = _MASTER_CHEF;
        SUSHI = _sushi;
        MASTER_PID = _MASTER_PID;
    }

    /// @notice Deposits a dummy token to `MASTER_CHEF` MCV1. This is required because MCV1 holds the minting rights for SUSHI.
    /// Any balance of transaction sender in `dummyToken` is transferred.
    /// The allocation point for the pool on MCV1 is the total allocation point for all pools that receive double incentives.
    /// @param dummyToken The address of the ERC-20 token to deposit into MCV1.
    function init(IERC20 dummyToken) external {
        uint256 balance = dummyToken.balanceOf(msg.sender);
        require(balance != 0, "MasterChefV2: Balance must exceed 0");
        dummyToken.safeTransferFrom(msg.sender, address(this), balance);
        dummyToken.approve(address(MASTER_CHEF), balance);
        MASTER_CHEF.deposit(MASTER_PID, balance);
        emit LogInit();
    }

    /// @notice Returns the number of MCV2 pools.
    function poolLength() public view returns (uint256 pools) {
        pools = poolInfo.length;
    }

    /// @notice Add a new LP to the pool. Can only be called by the owner.
    /// DO NOT add the same LP token more than once. Rewards will be messed up if you do.
    /// @param allocPoint AP of the new pool.
    /// @param _lpToken Address of the LP ERC-20 token.
    /// @param _rewarder Address of the rewarder delegate.
    function add(
        uint256 allocPoint,
        IERC20 _lpToken,
        IRewarder _rewarder
    ) public onlyOwner {
        uint256 lastRewardBlock = block.number;
        totalAllocPoint = totalAllocPoint.add(allocPoint);
        lpToken.push(_lpToken);
        rewarder.push(_rewarder);

        poolInfo.push(
            PoolInfo({
                allocPoint: allocPoint.to64(),
                lastRewardBlock: lastRewardBlock.to64(),
                accSushiPerShare: 0
            })
        );
        emit LogPoolAddition(
            lpToken.length.sub(1),
            allocPoint,
            _lpToken,
            _rewarder
        );
    }

    /// @notice Update the given pool's SUSHI allocation point and `IRewarder` contract. Can only be called by the owner.
    /// @param _pid The index of the pool. See `poolInfo`.
    /// @param _allocPoint New AP of the pool.
    /// @param _rewarder Address of the rewarder delegate.
    /// @param overwrite True if _rewarder should be `set`. Otherwise `_rewarder` is ignored.
    function set(
        uint256 _pid,
        uint256 _allocPoint,
        IRewarder _rewarder,
        bool overwrite
    ) public onlyOwner {
        totalAllocPoint = totalAllocPoint.sub(poolInfo[_pid].allocPoint).add(
            _allocPoint
        );
        poolInfo[_pid].allocPoint = _allocPoint.to64();
        if (overwrite) {
            rewarder[_pid] = _rewarder;
        }
        emit LogSetPool(
            _pid,
            _allocPoint,
            overwrite ? _rewarder : rewarder[_pid],
            overwrite
        );
    }

    /// @notice Set the `migrator` contract. Can only be called by the owner.
    /// @param _migrator The contract address to set.
    function setMigrator(IMigratorChef _migrator) public onlyOwner {
        migrator = _migrator;
    }

    /// @notice Migrate LP token to another LP contract through the `migrator` contract.
    /// @param _pid The index of the pool. See `poolInfo`.
    function migrate(uint256 _pid) public {
        require(
            address(migrator) != address(0),
            "MasterChefV2: no migrator set"
        );
        IERC20 _lpToken = lpToken[_pid];
        uint256 bal = _lpToken.balanceOf(address(this));
        _lpToken.approve(address(migrator), bal);
        IERC20 newLpToken = migrator.migrate(_lpToken);
        require(
            bal == newLpToken.balanceOf(address(this)),
            "MasterChefV2: migrated balance must match"
        );
        lpToken[_pid] = newLpToken;
    }

    /// @notice View function to see pending SUSHI on frontend.
    /// @param _pid The index of the pool. See `poolInfo`.
    /// @param _user Address of user.
    /// @return pending SUSHI reward for a given user.
    function pendingSushi(uint256 _pid, address _user)
        external
        view
        returns (uint256 pending)
    {
        PoolInfo memory pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_user];
        uint256 accSushiPerShare = pool.accSushiPerShare;
        uint256 lpSupply = lpToken[_pid].balanceOf(address(this));
        if (block.number > pool.lastRewardBlock && lpSupply != 0) {
            uint256 blocks = block.number.sub(pool.lastRewardBlock);
            uint256 sushiReward =
                blocks.mul(sushiPerBlock()).mul(pool.allocPoint) /
                    totalAllocPoint;
            accSushiPerShare = accSushiPerShare.add(
                sushiReward.mul(ACC_SUSHI_PRECISION) / lpSupply
            );
        }
        pending = int256(
            user.amount.mul(accSushiPerShare) / ACC_SUSHI_PRECISION
        )
            .sub(user.rewardDebt)
            .toUInt256();
    }

    /// @notice Update reward variables for all pools. Be careful of gas spending!
    /// @param pids Pool IDs of all to be updated. Make sure to update all active pools.
    function massUpdatePools(uint256[] calldata pids) external {
        uint256 len = pids.length;
        for (uint256 i = 0; i < len; ++i) {
            updatePool(pids[i]);
        }
    }

    /// @notice Calculates and returns the `amount` of SUSHI per block.
    function sushiPerBlock() public view returns (uint256 amount) {
        amount =
            uint256(MASTERCHEF_SUSHI_PER_BLOCK).mul(
                MASTER_CHEF.poolInfo(MASTER_PID).allocPoint
            ) /
            MASTER_CHEF.totalAllocPoint();
    }

    /// @notice Update reward variables of the given pool.
    /// @param pid The index of the pool. See `poolInfo`.
    /// @return pool Returns the pool that was updated.
    function updatePool(uint256 pid) public returns (PoolInfo memory pool) {
        pool = poolInfo[pid];
        if (block.number > pool.lastRewardBlock) {
            uint256 lpSupply = lpToken[pid].balanceOf(address(this));
            if (lpSupply > 0) {
                uint256 blocks = block.number.sub(pool.lastRewardBlock);
                uint256 sushiReward =
                    blocks.mul(sushiPerBlock()).mul(pool.allocPoint) /
                        totalAllocPoint;
                pool.accSushiPerShare = pool.accSushiPerShare.add(
                    (sushiReward.mul(ACC_SUSHI_PRECISION) / lpSupply).to128()
                );
            }
            pool.lastRewardBlock = block.number.to64();
            poolInfo[pid] = pool;
            emit LogUpdatePool(
                pid,
                pool.lastRewardBlock,
                lpSupply,
                pool.accSushiPerShare
            );
        }
    }

    /// @notice Deposit LP tokens to MCV2 for SUSHI allocation.
    /// @param pid The index of the pool. See `poolInfo`.
    /// @param amount LP token amount to deposit.
    /// @param to The receiver of `amount` deposit benefit.
    function deposit(
        uint256 pid,
        uint256 amount,
        address to
    ) public {
        PoolInfo memory pool = updatePool(pid);
        UserInfo storage user = userInfo[pid][to];

        // Effects
        user.amount = user.amount.add(amount);
        user.rewardDebt = user.rewardDebt.add(
            int256(amount.mul(pool.accSushiPerShare) / ACC_SUSHI_PRECISION)
        );

        // Interactions
        IRewarder _rewarder = rewarder[pid];
        if (address(_rewarder) != address(0)) {
            _rewarder.onSushiReward(pid, to, to, 0, user.amount);
        }

        lpToken[pid].safeTransferFrom(msg.sender, address(this), amount);

        emit Deposit(msg.sender, pid, amount, to);
    }

    /// @notice Withdraw LP tokens from MCV2.
    /// @param pid The index of the pool. See `poolInfo`.
    /// @param amount LP token amount to withdraw.
    /// @param to Receiver of the LP tokens.
    function withdraw(
        uint256 pid,
        uint256 amount,
        address to
    ) public {
        PoolInfo memory pool = updatePool(pid);
        UserInfo storage user = userInfo[pid][msg.sender];

        // Effects
        user.rewardDebt = user.rewardDebt.sub(
            int256(amount.mul(pool.accSushiPerShare) / ACC_SUSHI_PRECISION)
        );
        user.amount = user.amount.sub(amount);

        // Interactions
        IRewarder _rewarder = rewarder[pid];
        if (address(_rewarder) != address(0)) {
            _rewarder.onSushiReward(pid, msg.sender, to, 0, user.amount);
        }

        lpToken[pid].safeTransfer(to, amount);

        emit Withdraw(msg.sender, pid, amount, to);
    }

    /// @notice Harvest proceeds for transaction sender to `to`.
    /// @param pid The index of the pool. See `poolInfo`.
    /// @param to Receiver of SUSHI rewards.
    function harvest(uint256 pid, address to) public {
        PoolInfo memory pool = updatePool(pid);
        UserInfo storage user = userInfo[pid][msg.sender];
        int256 accumulatedSushi =
            int256(
                user.amount.mul(pool.accSushiPerShare) / ACC_SUSHI_PRECISION
            );
        uint256 _pendingSushi =
            accumulatedSushi.sub(user.rewardDebt).toUInt256();

        // Effects
        user.rewardDebt = accumulatedSushi;

        // Interactions
        if (_pendingSushi != 0) {
            SUSHI.safeTransfer(to, _pendingSushi);
        }

        IRewarder _rewarder = rewarder[pid];
        if (address(_rewarder) != address(0)) {
            _rewarder.onSushiReward(
                pid,
                msg.sender,
                to,
                _pendingSushi,
                user.amount
            );
        }

        emit Harvest(msg.sender, pid, _pendingSushi);
    }

    /// @notice Withdraw LP tokens from MCV2 and harvest proceeds for transaction sender to `to`.
    /// @param pid The index of the pool. See `poolInfo`.
    /// @param amount LP token amount to withdraw.
    /// @param to Receiver of the LP tokens and SUSHI rewards.
    function withdrawAndHarvest(
        uint256 pid,
        uint256 amount,
        address to
    ) public {
        PoolInfo memory pool = updatePool(pid);
        UserInfo storage user = userInfo[pid][msg.sender];
        int256 accumulatedSushi =
            int256(
                user.amount.mul(pool.accSushiPerShare) / ACC_SUSHI_PRECISION
            );
        uint256 _pendingSushi =
            accumulatedSushi.sub(user.rewardDebt).toUInt256();

        // Effects
        user.rewardDebt = accumulatedSushi.sub(
            int256(amount.mul(pool.accSushiPerShare) / ACC_SUSHI_PRECISION)
        );
        user.amount = user.amount.sub(amount);

        // Interactions
        SUSHI.safeTransfer(to, _pendingSushi);

        IRewarder _rewarder = rewarder[pid];
        if (address(_rewarder) != address(0)) {
            _rewarder.onSushiReward(
                pid,
                msg.sender,
                to,
                _pendingSushi,
                user.amount
            );
        }

        lpToken[pid].safeTransfer(to, amount);

        emit Withdraw(msg.sender, pid, amount, to);
        emit Harvest(msg.sender, pid, _pendingSushi);
    }

    /// @notice Harvests SUSHI from `MASTER_CHEF` MCV1 and pool `MASTER_PID` to this MCV2 contract.
    function harvestFromMasterChef() public {
        MASTER_CHEF.deposit(MASTER_PID, 0);
    }

    /// @notice Withdraw without caring about rewards. EMERGENCY ONLY.
    /// @param pid The index of the pool. See `poolInfo`.
    /// @param to Receiver of the LP tokens.
    function emergencyWithdraw(uint256 pid, address to) public {
        UserInfo storage user = userInfo[pid][msg.sender];
        uint256 amount = user.amount;
        user.amount = 0;
        user.rewardDebt = 0;

        IRewarder _rewarder = rewarder[pid];
        if (address(_rewarder) != address(0)) {
            _rewarder.onSushiReward(pid, msg.sender, to, 0, 0);
        }

        // Note: transfer can fail or succeed if `amount` is zero.
        lpToken[pid].safeTransfer(to, amount);
        emit EmergencyWithdraw(msg.sender, pid, amount, to);
    }
}

// File: @boringcrypto/boring-solidity/contracts/interfaces/IERC20.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.6.12;

interface IERC20 {
    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 amount) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);

    // EIP 2612
    function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external;
}
// File: @boringcrypto/boring-solidity/contracts/BoringBatchable.sol



// SPDX-License-Identifier: UNLICENSED
// Audit on 5-Jan-2021 by Keno and BoringCrypto

// P1 - P3: OK
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;
// solhint-disable avoid-low-level-calls

import "./libraries/BoringERC20.sol";

// T1 - T4: OK
contract BaseBoringBatchable {
    function _getRevertMsg(bytes memory _returnData) internal pure returns (string memory) {
        // If the _res length is less than 68, then the transaction failed silently (without a revert message)
        if (_returnData.length < 68) return "Transaction reverted silently";

        assembly {
            // Slice the sighash.
            _returnData := add(_returnData, 0x04)
        }
        return abi.decode(_returnData, (string)); // All that remains is the revert string
    }    
    
    // F3 - F9: OK
    // F1: External is ok here because this is the batch function, adding it to a batch makes no sense
    // F2: Calls in the batch may be payable, delegatecall operates in the same context, so each call in the batch has access to msg.value
    // C1 - C21: OK
    // C3: The length of the loop is fully under user control, so can't be exploited
    // C7: Delegatecall is only used on the same contract, so it's safe
    function batch(bytes[] calldata calls, bool revertOnFail) external payable returns(bool[] memory successes, bytes[] memory results) {
        // Interactions
        successes = new bool[](calls.length);
        results = new bytes[](calls.length);
        for (uint256 i = 0; i < calls.length; i++) {
            (bool success, bytes memory result) = address(this).delegatecall(calls[i]);
            require(success || !revertOnFail, _getRevertMsg(result));
            successes[i] = success;
            results[i] = result;
        }
    }
}

// T1 - T4: OK
contract BoringBatchable is BaseBoringBatchable {
    // F1 - F9: OK
    // F6: Parameters can be used front-run the permit and the user's permit will fail (due to nonce or other revert)
    //     if part of a batch this could be used to grief once as the second call would not need the permit
    // C1 - C21: OK
    function permitToken(IERC20 token, address from, address to, uint256 amount, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
        // Interactions
        // X1 - X5
        token.permit(from, to, amount, deadline, v, r, s);
    }
}
// File: contracts/sushi/libraries/SignedSafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

library SignedSafeMath {
    int256 private constant _INT256_MIN = -2**255;

    /**
     * @dev Returns the multiplication of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(int256 a, int256 b) internal pure returns (int256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        require(
            !(a == -1 && b == _INT256_MIN),
            "SignedSafeMath: multiplication overflow"
        );

        int256 c = a * b;
        require(c / a == b, "SignedSafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two signed integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(int256 a, int256 b) internal pure returns (int256) {
        require(b != 0, "SignedSafeMath: division by zero");
        require(
            !(b == -1 && a == _INT256_MIN),
            "SignedSafeMath: division overflow"
        );

        int256 c = a / b;

        return c;
    }

    /**
     * @dev Returns the subtraction of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        require(
            (b >= 0 && c <= a) || (b < 0 && c > a),
            "SignedSafeMath: subtraction overflow"
        );

        return c;
    }

    /**
     * @dev Returns the addition of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        require(
            (b >= 0 && c >= a) || (b < 0 && c < a),
            "SignedSafeMath: addition overflow"
        );

        return c;
    }

    function toUInt256(int256 a) internal pure returns (uint256) {
        require(a >= 0, "Integer < 0");
        return uint256(a);
    }
}

// File: contracts/sushi/interfaces/IMasterChef.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;
import "@boringcrypto/boring-solidity/contracts/libraries/BoringERC20.sol";

interface IMasterChef {
    using BoringERC20 for IERC20;
    struct UserInfo {
        uint256 amount; // How many LP tokens the user has provided.
        uint256 rewardDebt; // Reward debt. See explanation below.
    }

    struct PoolInfo {
        IERC20 lpToken; // Address of LP token contract.
        uint256 allocPoint; // How many allocation points assigned to this pool. SUSHI to distribute per block.
        uint256 lastRewardBlock; // Last block number that SUSHI distribution occurs.
        uint256 accSushiPerShare; // Accumulated SUSHI per share, times 1e12. See below.
    }

    function poolInfo(uint256 pid)
        external
        view
        returns (IMasterChef.PoolInfo memory);

    function totalAllocPoint() external view returns (uint256);

    function deposit(uint256 _pid, uint256 _amount) external;
}