// File: contracts/strategies/convex/ConvexStrategyMIMMainnet.sol



pragma solidity 0.5.16;

import "./base/ConvexStrategyUL.sol";

contract ConvexStrategyMIMMainnet is ConvexStrategyUL {

  address public mim_unused; // just a differentiator for the bytecode

  constructor() public {}

  function initializeStrategy(
    address _storage,
    address _vault
  ) public initializer {
    address underlying = address(0x5a6A4D54456819380173272A5E8E9B9904BdF41B);
    address rewardPool = address(0xFd5AbF66b003881b88567EB9Ed9c651F14Dc4771);
    address crv = address(0xD533a949740bb3306d119CC777fa900bA034cd52);
    address cvx = address(0x4e3FBD56CD56c3e72c1403e103b45Db9da5B9D2B);
    address spell = address(0x090185f2135308BaD17527004364eBcC2D37e5F6);
    address dai = address(0x6B175474E89094C44Da98b954EedeAC495271d0F);
    address metaCurveDeposit = address(0xA79828DF1850E8a3A3064576f380D90aECDD3359);
    bytes32 sushiDex = bytes32(0xcb2d20206d906069351c89a2cb7cdbd96c71998717cd5a82e724d955b654f67a);
    ConvexStrategyUL.initializeBaseStrategy(
      _storage,
      underlying,
      _vault,
      rewardPool, //rewardPool
      40,  // Pool id
      dai,
      1, //depositArrayPosition
      metaCurveDeposit,
      4, //nTokens
      true //metaPool
    );
    rewardTokens = [crv, cvx, spell];
    storedLiquidationPaths[crv][weth] = [crv, weth];
    storedLiquidationDexes[crv][weth] = [sushiDex];
    storedLiquidationPaths[cvx][weth] = [cvx, weth];
    storedLiquidationDexes[cvx][weth] = [sushiDex];
    storedLiquidationPaths[spell][weth] = [spell, weth];
    storedLiquidationDexes[spell][weth] = [sushiDex];
    storedLiquidationPaths[weth][dai] = [weth, dai];
    storedLiquidationDexes[weth][dai] = [sushiDex];
  }
}

// File: contracts/strategies/convex/base/ConvexStrategyUL.sol



pragma solidity 0.5.16;

import "@openzeppelin/contracts/math/Math.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/ERC20Detailed.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "../../../base/interface/uniswap/IUniswapV2Router02.sol";
import "../../../base/interface/IStrategy.sol";
import "../../../base/interface/IVault.sol";
import "../../../base/upgradability/BaseUpgradeableStrategyUL.sol";
import "../../../base/interface/uniswap/IUniswapV2Pair.sol";
import "../interface/IBooster.sol";
import "../interface/IBaseRewardPool.sol";
import "../../../base/interface/curve/ICurveDeposit_2token.sol";
import "../../../base/interface/curve/ICurveDeposit_3token.sol";
import "../../../base/interface/curve/ICurveDeposit_4token.sol";
import "../../../base/interface/curve/ICurveDeposit_4token_meta.sol";

contract ConvexStrategyUL is IStrategy, BaseUpgradeableStrategyUL {

  using SafeMath for uint256;
  using SafeERC20 for IERC20;

  address public constant booster = address(0xF403C135812408BFbE8713b5A23a04b3D48AAE31);
  address public constant weth = address(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2);
  address public constant multiSigAddr = 0xF49440C1F012d041802b25A73e5B0B9166a75c02;

  // additional storage slots (on top of BaseUpgradeableStrategy ones) are defined here
  bytes32 internal constant _POOLID_SLOT = 0x3fd729bfa2e28b7806b03a6e014729f59477b530f995be4d51defc9dad94810b;
  bytes32 internal constant _DEPOSIT_TOKEN_SLOT = 0x219270253dbc530471c88a9e7c321b36afda219583431e7b6c386d2d46e70c86;
  bytes32 internal constant _DEPOSIT_RECEIPT_SLOT = 0x414478d5ad7f54ead8a3dd018bba4f8d686ba5ab5975cd376e0c98f98fb713c5;
  bytes32 internal constant _DEPOSIT_ARRAY_POSITION_SLOT = 0xb7c50ef998211fff3420379d0bf5b8dfb0cee909d1b7d9e517f311c104675b09;
  bytes32 internal constant _CURVE_DEPOSIT_SLOT = 0xb306bb7adebd5a22f5e4cdf1efa00bc5f62d4f5554ef9d62c1b16327cd3ab5f9;
  bytes32 internal constant _HODL_RATIO_SLOT = 0xb487e573671f10704ed229d25cf38dda6d287a35872859d096c0395110a0adb1;
  bytes32 internal constant _HODL_VAULT_SLOT = 0xc26d330f887c749cb38ae7c37873ff08ac4bba7aec9113c82d48a0cf6cc145f2;
  bytes32 internal constant _NTOKENS_SLOT = 0xbb60b35bae256d3c1378ff05e8d7bee588cd800739c720a107471dfa218f74c1;
  bytes32 internal constant _METAPOOL_SLOT = 0x567ad8b67c826974a167f1a361acbef5639a3e7e02e99edbc648a84b0923d5b7;

  uint256 public constant hodlRatioBase = 10000;
  address[] public rewardTokens;

  constructor() public BaseUpgradeableStrategyUL() {
    assert(_POOLID_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.poolId")) - 1));
    assert(_DEPOSIT_TOKEN_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.depositToken")) - 1));
    assert(_DEPOSIT_RECEIPT_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.depositReceipt")) - 1));
    assert(_DEPOSIT_ARRAY_POSITION_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.depositArrayPosition")) - 1));
    assert(_CURVE_DEPOSIT_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.curveDeposit")) - 1));
    assert(_HODL_RATIO_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.hodlRatio")) - 1));
    assert(_HODL_VAULT_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.hodlVault")) - 1));
    assert(_NTOKENS_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.nTokens")) - 1));
    assert(_METAPOOL_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.metaPool")) - 1));

  }

  function initializeBaseStrategy(
    address _storage,
    address _underlying,
    address _vault,
    address _rewardPool,
    uint256 _poolID,
    address _depositToken,
    uint256 _depositArrayPosition,
    address _curveDeposit,
    uint256 _nTokens,
    bool _metaPool
  ) public initializer {

    BaseUpgradeableStrategyUL.initialize(
      _storage,
      _underlying,
      _vault,
      _rewardPool,
      weth,
      300,  // profit sharing numerator
      1000, // profit sharing denominator
      true, // sell
      0, // sell floor
      12 hours, // implementation change delay
      address(0x7882172921E99d590E097cD600554339fBDBc480) //UL Registry
    );

    address _lpt;
    address _depositReceipt;
    (_lpt,_depositReceipt,,,,) = IBooster(booster).poolInfo(_poolID);
    require(_lpt == underlying(), "Pool Info does not match underlying");
    require(_depositArrayPosition < _nTokens, "Deposit array position out of bounds");
    require(1 < _nTokens && _nTokens < 5, "_nTokens should be 2, 3 or 4");
    _setDepositArrayPosition(_depositArrayPosition);
    _setPoolId(_poolID);
    _setDepositToken(_depositToken);
    _setDepositReceipt(_depositReceipt);
    _setCurveDeposit(_curveDeposit);
    _setNTokens(_nTokens);
    _setMetaPool(_metaPool);
    setHodlRatio(1000);
    setHodlVault(multiSigAddr);
    rewardTokens = new address[](0);
  }

  function setHodlRatio(uint256 _value) public onlyGovernance {
    setUint256(_HODL_RATIO_SLOT, _value);
  }

  function hodlRatio() public view returns (uint256) {
    return getUint256(_HODL_RATIO_SLOT);
  }

  function setHodlVault(address _address) public onlyGovernance {
    setAddress(_HODL_VAULT_SLOT, _address);
  }

  function hodlVault() public view returns (address) {
    return getAddress(_HODL_VAULT_SLOT);
  }

  function depositArbCheck() public view returns(bool) {
    return true;
  }

  function rewardPoolBalance() internal view returns (uint256 bal) {
      bal = IBaseRewardPool(rewardPool()).balanceOf(address(this));
  }

  function exitRewardPool() internal {
      uint256 stakedBalance = rewardPoolBalance();
      if (stakedBalance != 0) {
          IBaseRewardPool(rewardPool()).withdrawAll(true);
      }
      uint256 depositBalance = IERC20(depositReceipt()).balanceOf(address(this));
      if (depositBalance != 0) {
        IBooster(booster).withdrawAll(poolId());
      }
  }

  function partialWithdrawalRewardPool(uint256 amount) internal {
    IBaseRewardPool(rewardPool()).withdraw(amount, false);  //don't claim rewards at this point
    uint256 depositBalance = IERC20(depositReceipt()).balanceOf(address(this));
    if (depositBalance != 0) {
      IBooster(booster).withdrawAll(poolId());
    }
  }

  function emergencyExitRewardPool() internal {
    uint256 stakedBalance = rewardPoolBalance();
    if (stakedBalance != 0) {
        IBaseRewardPool(rewardPool()).withdrawAll(false); //don't claim rewards
    }
    uint256 depositBalance = IERC20(depositReceipt()).balanceOf(address(this));
    if (depositBalance != 0) {
      IBooster(booster).withdrawAll(poolId());
    }
  }

  function unsalvagableTokens(address token) public view returns (bool) {
    return (token == rewardToken() || token == underlying() || token == depositReceipt());
  }

  function enterRewardPool() internal {
    uint256 entireBalance = IERC20(underlying()).balanceOf(address(this));
    IERC20(underlying()).safeApprove(booster, 0);
    IERC20(underlying()).safeApprove(booster, entireBalance);
    IBooster(booster).depositAll(poolId(), true); //deposit and stake
  }

  /*
  *   In case there are some issues discovered about the pool or underlying asset
  *   Governance can exit the pool properly
  *   The function is only used for emergency to exit the pool
  */
  function emergencyExit() public onlyGovernance {
    emergencyExitRewardPool();
    _setPausedInvesting(true);
  }

  /*
  *   Resumes the ability to invest into the underlying reward pools
  */

  function continueInvesting() public onlyGovernance {
    _setPausedInvesting(false);
  }

  function addRewardToken(address _token) public onlyGovernance {
    rewardTokens.push(_token);
  }

  // We assume that all the tradings can be done on Sushiswap
  function _liquidateReward() internal {
    if (!sell()) {
      // Profits can be disabled for possible simplified and rapoolId exit
      emit ProfitsNotCollected(sell(), false);
      return;
    }

    for(uint256 i = 0; i < rewardTokens.length; i++){
      address token = rewardTokens[i];
      uint256 rewardBalance = IERC20(token).balanceOf(address(this));
      if (rewardBalance == 0 || storedLiquidationDexes[token][weth].length < 1) {
        continue;
      }

      uint256 toHodl = rewardBalance.mul(hodlRatio()).div(hodlRatioBase);
      if (toHodl > 0) {
        IERC20(token).safeTransfer(hodlVault(), toHodl);
        rewardBalance = rewardBalance.sub(toHodl);
        if (rewardBalance == 0) {
          continue;
        }
      }
      IERC20(token).safeApprove(universalLiquidator(), 0);
      IERC20(token).safeApprove(universalLiquidator(), rewardBalance);
      // we can accept 1 as the minimum because this will be called only by a trusted worker
      ILiquidator(universalLiquidator()).swapTokenOnMultipleDEXes(
        rewardBalance,
        1,
        address(this), // target
        storedLiquidationDexes[token][weth],
        storedLiquidationPaths[token][weth]
      );
    }

    uint256 rewardBalance = IERC20(weth).balanceOf(address(this));

    notifyProfitInRewardToken(rewardBalance);
    uint256 remainingRewardBalance = IERC20(rewardToken()).balanceOf(address(this));

    if (remainingRewardBalance == 0) {
      return;
    }

    IERC20(rewardToken()).safeApprove(universalLiquidator(), 0);
    IERC20(rewardToken()).safeApprove(universalLiquidator(), remainingRewardBalance);

    // we can accept 1 as minimum because this is called only by a trusted role
    ILiquidator(universalLiquidator()).swapTokenOnMultipleDEXes(
      remainingRewardBalance,
      1,
      address(this), // target
      storedLiquidationDexes[weth][depositToken()],
      storedLiquidationPaths[weth][depositToken()]
    );

    uint256 tokenBalance = IERC20(depositToken()).balanceOf(address(this));
    if (tokenBalance > 0) {
      depositCurve();
    }
  }

  function depositCurve() internal {
    uint256 tokenBalance = IERC20(depositToken()).balanceOf(address(this));
    IERC20(depositToken()).safeApprove(curveDeposit(), 0);
    IERC20(depositToken()).safeApprove(curveDeposit(), tokenBalance);

    // we can accept 0 as minimum, this will be called only by trusted roles
    uint256 minimum = 0;
    if (nTokens() == 2) {
      uint256[2] memory depositArray;
      depositArray[depositArrayPosition()] = tokenBalance;
      ICurveDeposit_2token(curveDeposit()).add_liquidity(depositArray, minimum);
    } else if (nTokens() == 3) {
      uint256[3] memory depositArray;
      depositArray[depositArrayPosition()] = tokenBalance;
      ICurveDeposit_3token(curveDeposit()).add_liquidity(depositArray, minimum);
    } else if (nTokens() == 4) {
      uint256[4] memory depositArray;
      depositArray[depositArrayPosition()] = tokenBalance;
      if (metaPool()) {
        ICurveDeposit_4token_meta(curveDeposit()).add_liquidity(underlying(), depositArray, minimum);
      } else {
        ICurveDeposit_4token(curveDeposit()).add_liquidity(depositArray, minimum);
      }
    }
  }


  /*
  *   Stakes everything the strategy holds into the reward pool
  */
  function investAllUnderlying() internal onlyNotPausedInvesting {
    // this check is needed, because most of the SNX reward pools will revert if
    // you try to stake(0).
    if(IERC20(underlying()).balanceOf(address(this)) > 0) {
      enterRewardPool();
    }
  }

  /*
  *   Withdraws all the asset to the vault
  */
  function withdrawAllToVault() public restricted {
    if (address(rewardPool()) != address(0)) {
      exitRewardPool();
    }
    _liquidateReward();
    IERC20(underlying()).safeTransfer(vault(), IERC20(underlying()).balanceOf(address(this)));
  }

  /*
  *   Withdraws all the asset to the vault
  */
  function withdrawToVault(uint256 amount) public restricted {
    // Typically there wouldn't be any amount here
    // however, it is possible because of the emergencyExit
    uint256 entireBalance = IERC20(underlying()).balanceOf(address(this));

    if(amount > entireBalance){
      // While we have the check above, we still using SafeMath below
      // for the peace of mind (in case something gets changed in between)
      uint256 needToWithdraw = amount.sub(entireBalance);
      uint256 toWithdraw = Math.min(rewardPoolBalance(), needToWithdraw);
      partialWithdrawalRewardPool(toWithdraw);
    }
    IERC20(underlying()).safeTransfer(vault(), amount);
  }

  /*
  *   Note that we currently do not have a mechanism here to include the
  *   amount of reward that is accrued.
  */
  function investedUnderlyingBalance() external view returns (uint256) {
    return rewardPoolBalance()
      .add(IERC20(depositReceipt()).balanceOf(address(this)))
      .add(IERC20(underlying()).balanceOf(address(this)));
  }

  /*
  *   Governance or Controller can claim coins that are somehow transferred into the contract
  *   Note that they cannot come in take away coins that are used and defined in the strategy itself
  */
  function salvage(address recipient, address token, uint256 amount) external onlyControllerOrGovernance {
     // To make sure that governance cannot come in and take away the coins
    require(!unsalvagableTokens(token), "token is defined as not salvagable");
    IERC20(token).safeTransfer(recipient, amount);
  }

  /*
  *   Get the reward, sell it in exchange for underlying, invest what you got.
  *   It's not much, but it's honest work.
  *
  *   Note that although `onlyNotPausedInvesting` is not added here,
  *   calling `investAllUnderlying()` affectively blocks the usage of `doHardWork`
  *   when the investing is being paused by governance.
  */
  function doHardWork() external onlyNotPausedInvesting restricted {
    IBaseRewardPool(rewardPool()).getReward();
    _liquidateReward();
    investAllUnderlying();
  }

  /**
  * Can completely disable claiming UNI rewards and selling. Good for emergency withdraw in the
  * simplest possible way.
  */
  function setSell(bool s) public onlyGovernance {
    _setSell(s);
  }

  /**
  * Sets the minimum amount of CRV needed to trigger a sale.
  */
  function setSellFloor(uint256 floor) public onlyGovernance {
    _setSellFloor(floor);
  }

  // masterchef rewards pool ID
  function _setPoolId(uint256 _value) internal {
    setUint256(_POOLID_SLOT, _value);
  }

  function poolId() public view returns (uint256) {
    return getUint256(_POOLID_SLOT);
  }

  function _setDepositToken(address _address) internal {
    setAddress(_DEPOSIT_TOKEN_SLOT, _address);
  }

  function depositToken() public view returns (address) {
    return getAddress(_DEPOSIT_TOKEN_SLOT);
  }

  function _setDepositReceipt(address _address) internal {
    setAddress(_DEPOSIT_RECEIPT_SLOT, _address);
  }

  function depositReceipt() public view returns (address) {
    return getAddress(_DEPOSIT_RECEIPT_SLOT);
  }

  function _setDepositArrayPosition(uint256 _value) internal {
    setUint256(_DEPOSIT_ARRAY_POSITION_SLOT, _value);
  }

  function depositArrayPosition() public view returns (uint256) {
    return getUint256(_DEPOSIT_ARRAY_POSITION_SLOT);
  }

  function _setCurveDeposit(address _address) internal {
    setAddress(_CURVE_DEPOSIT_SLOT, _address);
  }

  function curveDeposit() public view returns (address) {
    return getAddress(_CURVE_DEPOSIT_SLOT);
  }

  function _setNTokens(uint256 _value) internal {
    setUint256(_NTOKENS_SLOT, _value);
  }

  function nTokens() public view returns (uint256) {
    return getUint256(_NTOKENS_SLOT);
  }

  function _setMetaPool(bool _value) internal {
    setBoolean(_METAPOOL_SLOT, _value);
  }

  function metaPool() public view returns (bool) {
    return getBoolean(_METAPOOL_SLOT);
  }


  function finalizeUpgrade() external onlyGovernance {
    _finalizeUpgrade();
    setHodlVault(multiSigAddr);
    setHodlRatio(1000); // 10%
  }
}

// File: @openzeppelin/contracts/math/Math.sol



pragma solidity ^0.5.0;

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

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

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

// File: @openzeppelin/contracts/math/SafeMath.sol



pragma solidity ^0.5.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

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

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     *
     * _Available since v2.4.0._
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

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

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

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

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts/token/ERC20/ERC20Detailed.sol



pragma solidity ^0.5.0;

import "./IERC20.sol";

/**
 * @dev Optional functions from the ERC20 standard.
 */
contract ERC20Detailed is IERC20 {
    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for `name`, `symbol`, and `decimals`. All three of
     * these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name, string memory symbol, uint8 decimals) public {
        _name = name;
        _symbol = symbol;
        _decimals = decimals;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view returns (uint8) {
        return _decimals;
    }
}

// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol



pragma solidity ^0.5.0;

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

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

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

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

    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

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

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves.

        // A Solidity high level call has three parts:
        //  1. The target address is checked to verify it contains contract code
        //  2. The call itself is made, and success asserted
        //  3. The return value is decoded, which in turn checks the size of the returned data.
        // solhint-disable-next-line max-line-length
        require(address(token).isContract(), "SafeERC20: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success, "SafeERC20: low-level call failed");

        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// File: contracts/base/interface/uniswap/IUniswapV2Router02.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;

import './IUniswapV2Router01.sol';

interface IUniswapV2Router02 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);

    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// File: contracts/base/interface/IStrategy.sol



pragma solidity 0.5.16;

interface IStrategy {
    
    function unsalvagableTokens(address tokens) external view returns (bool);
    
    function governance() external view returns (address);
    function controller() external view returns (address);
    function underlying() external view returns (address);
    function vault() external view returns (address);

    function withdrawAllToVault() external;
    function withdrawToVault(uint256 amount) external;

    function investedUnderlyingBalance() external view returns (uint256); // itsNotMuch()

    // should only be called by controller
    function salvage(address recipient, address token, uint256 amount) external;

    function doHardWork() external;
    function depositArbCheck() external view returns(bool);
}

// File: contracts/base/interface/IVault.sol



pragma solidity 0.5.16;

interface IVault {

    function initializeVault(
      address _storage,
      address _underlying,
      uint256 _toInvestNumerator,
      uint256 _toInvestDenominator
    ) external ;

    function balanceOf(address) external view returns (uint256);

    function underlyingBalanceInVault() external view returns (uint256);
    function underlyingBalanceWithInvestment() external view returns (uint256);

    // function store() external view returns (address);
    function governance() external view returns (address);
    function controller() external view returns (address);
    function underlying() external view returns (address);
    function strategy() external view returns (address);

    function setStrategy(address _strategy) external;
    function announceStrategyUpdate(address _strategy) external;
    function setVaultFractionToInvest(uint256 numerator, uint256 denominator) external;

    function deposit(uint256 amountWei) external;
    function depositFor(uint256 amountWei, address holder) external;

    function withdrawAll() external;
    function withdraw(uint256 numberOfShares) external;
    function getPricePerFullShare() external view returns (uint256);

    function underlyingBalanceWithInvestmentForHolder(address holder) view external returns (uint256);

    // hard work should be callable only by the controller (by the hard worker) or by governance
    function doHardWork() external;
}

// File: contracts/base/upgradability/BaseUpgradeableStrategyUL.sol



pragma solidity 0.5.16;

import "@openzeppelin/upgrades/contracts/Initializable.sol";
import "./BaseUpgradeableStrategyStorage.sol";
import "../inheritance/ControllableInit.sol";
import "../interface/IController.sol";
import "../interface/IFeeRewardForwarderV6.sol";
import "../interface/ILiquidator.sol";
import "../interface/ILiquidatorRegistry.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";

contract BaseUpgradeableStrategyUL is Initializable, ControllableInit, BaseUpgradeableStrategyStorage {
  using SafeMath for uint256;
  using SafeERC20 for IERC20;

  bytes32 internal constant _UL_REGISTRY_SLOT = 0x7a4b558e8ed4a66729f4a918db093413f0f1ae77c0de7c88bea8b99e084b2a17;
  bytes32 internal constant _UL_SLOT = 0xebfe408f65547b28326a79acf512c0f9a2bf4211ece39254d7c3ec96dd3dd242;

  mapping(address => mapping(address => address[])) public storedLiquidationPaths;
  mapping(address => mapping(address => bytes32[])) public storedLiquidationDexes;

  event ProfitsNotCollected(bool sell, bool floor);
  event ProfitLogInReward(uint256 profitAmount, uint256 feeAmount, uint256 timestamp);
  event ProfitAndBuybackLog(uint256 profitAmount, uint256 feeAmount, uint256 timestamp);

  modifier restricted() {
    require(msg.sender == vault() || msg.sender == controller()
      || msg.sender == governance(),
      "The sender has to be the controller, governance, or vault");
    _;
  }

  // This is only used in `investAllUnderlying()`
  // The user can still freely withdraw from the strategy
  modifier onlyNotPausedInvesting() {
    require(!pausedInvesting(), "Action blocked as the strategy is in emergency state");
    _;
  }

  constructor() public BaseUpgradeableStrategyStorage() {
    assert(_UL_REGISTRY_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.ULRegistry")) - 1));
    assert(_UL_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.UL")) - 1));
  }

  function initialize(
    address _storage,
    address _underlying,
    address _vault,
    address _rewardPool,
    address _rewardToken,
    uint256 _profitSharingNumerator,
    uint256 _profitSharingDenominator,
    bool _sell,
    uint256 _sellFloor,
    uint256 _implementationChangeDelay,
    address _universalLiquidatorRegistry
  ) public initializer {
    ControllableInit.initialize(
      _storage
    );
    _setUnderlying(_underlying);
    _setVault(_vault);
    _setRewardPool(_rewardPool);
    _setRewardToken(_rewardToken);
    _setProfitSharingNumerator(_profitSharingNumerator);
    _setProfitSharingDenominator(_profitSharingDenominator);

    _setSell(_sell);
    _setSellFloor(_sellFloor);
    _setNextImplementationDelay(_implementationChangeDelay);
    _setPausedInvesting(false);
    _setUniversalLiquidatorRegistry(_universalLiquidatorRegistry);
    _setUniversalLiquidator(ILiquidatorRegistry(universalLiquidatorRegistry()).universalLiquidator());
  }

  /**
  * Schedules an upgrade for this vault's proxy.
  */
  function scheduleUpgrade(address impl) public onlyGovernance {
    _setNextImplementation(impl);
    _setNextImplementationTimestamp(block.timestamp.add(nextImplementationDelay()));
  }

  function _finalizeUpgrade() internal {
    _setNextImplementation(address(0));
    _setNextImplementationTimestamp(0);
  }

  function shouldUpgrade() external view returns (bool, address) {
    return (
      nextImplementationTimestamp() != 0
        && block.timestamp > nextImplementationTimestamp()
        && nextImplementation() != address(0),
      nextImplementation()
    );
  }

  // reward notification

  function notifyProfitInRewardToken(uint256 _rewardBalance) internal {
    if( _rewardBalance > 0 ){
      uint256 feeAmount = _rewardBalance.mul(profitSharingNumerator()).div(profitSharingDenominator());
      emit ProfitLogInReward(_rewardBalance, feeAmount, block.timestamp);
      IERC20(rewardToken()).safeApprove(controller(), 0);
      IERC20(rewardToken()).safeApprove(controller(), feeAmount);

      IController(controller()).notifyFee(
        rewardToken(),
        feeAmount
      );
    } else {
      emit ProfitLogInReward(0, 0, block.timestamp);
    }
  }

  function notifyProfitAndBuybackInRewardToken(uint256 _rewardBalance, address pool, uint256 _buybackRatio) internal {
    if( _rewardBalance > 0 ){
      uint256 feeAmount = _rewardBalance.mul(profitSharingNumerator()).div(profitSharingDenominator());
      uint256 buybackAmount = _rewardBalance.sub(feeAmount).mul(_buybackRatio).div(10000);

      address forwarder = IController(controller()).feeRewardForwarder();
      emit ProfitAndBuybackLog(_rewardBalance, feeAmount, block.timestamp);

      IERC20(rewardToken()).safeApprove(forwarder, 0);
      IERC20(rewardToken()).safeApprove(forwarder, _rewardBalance);

      IFeeRewardForwarderV6(forwarder).notifyFeeAndBuybackAmounts(
        rewardToken(),
        feeAmount,
        pool,
        buybackAmount
      );
    } else {
      emit ProfitAndBuybackLog(0, 0, block.timestamp);
    }
  }

  function _setUniversalLiquidatorRegistry(address _address) internal {
    setAddress(_UL_REGISTRY_SLOT, _address);
  }

  function universalLiquidatorRegistry() public view returns (address) {
    return getAddress(_UL_REGISTRY_SLOT);
  }

  function _setUniversalLiquidator(address _address) internal {
    setAddress(_UL_SLOT, _address);
  }

  function universalLiquidator() public view returns (address) {
    return getAddress(_UL_SLOT);
  }

  function configureLiquidation(address[] memory path, bytes32[] memory dexes) public onlyGovernance {
    address fromToken = path[0];
    address toToken = path[path.length - 1];

    require(dexes.length == path.length - 1, "lengths do not match");

    storedLiquidationPaths[fromToken][toToken] = path;
    storedLiquidationDexes[fromToken][toToken] = dexes;
  }
}

// File: contracts/base/interface/uniswap/IUniswapV2Pair.sol



// SPDX-License-Identifier: MIT
/**
 *Submitted for verification at Etherscan.io on 2020-05-05
*/

// File: contracts/interfaces/IUniswapV2Pair.sol

pragma solidity >=0.5.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}
// File: contracts/strategies/convex/interface/IBooster.sol



pragma solidity 0.5.16;

interface IBooster {
    function deposit(uint256 _pid, uint256 _amount, bool _stake) external;
    function depositAll(uint256 _pid, bool _stake) external;
    function withdraw(uint256 _pid, uint256 _amount) external;
    function withdrawAll(uint256 _pid) external;
    function poolInfo(uint256 _pid) external view returns (address lpToken, address, address, address, address, bool);
    function earmarkRewards(uint256 _pid) external;
}

// File: contracts/strategies/convex/interface/IBaseRewardPool.sol



pragma solidity 0.5.16;

interface IBaseRewardPool {
    function balanceOf(address account) external view returns(uint256 amount);
    function pid() external view returns (uint256 _pid);
    function stakingToken() external view returns (address _stakingToken);
    function getReward() external;
    function stake(uint256 _amount) external;
    function stakeAll() external;
    function withdraw(uint256 amount, bool claim) external;
    function withdrawAll(bool claim) external;
    function withdrawAndUnwrap(uint256 amount, bool claim) external;
    function withdrawAllAndUnwrap(bool claim) external;
}

// File: contracts/base/interface/curve/ICurveDeposit_2token.sol



pragma solidity 0.5.16;

interface ICurveDeposit_2token {
  function get_virtual_price() external view returns (uint);
  function add_liquidity(
    uint256[2] calldata amounts,
    uint256 min_mint_amount
  ) external payable;
  function remove_liquidity_imbalance(
    uint256[2] calldata amounts,
    uint256 max_burn_amount
  ) external;
  function remove_liquidity(
    uint256 _amount,
    uint256[2] calldata amounts
  ) external;
  function exchange(
    int128 from, int128 to, uint256 _from_amount, uint256 _min_to_amount
  ) external payable;
  function calc_token_amount(
    uint256[2] calldata amounts,
    bool deposit
  ) external view returns(uint);
}

// File: contracts/base/interface/curve/ICurveDeposit_3token.sol



pragma solidity 0.5.16;

interface ICurveDeposit_3token {
  function get_virtual_price() external view returns (uint);
  function add_liquidity(
    uint256[3] calldata amounts,
    uint256 min_mint_amount
  ) external;
  function remove_liquidity_imbalance(
    uint256[3] calldata amounts,
    uint256 max_burn_amount
  ) external;
  function remove_liquidity(
    uint256 _amount,
    uint256[3] calldata amounts
  ) external;
  function exchange(
    int128 from, int128 to, uint256 _from_amount, uint256 _min_to_amount
  ) external;
  function calc_token_amount(
    uint256[3] calldata amounts,
    bool deposit
  ) external view returns(uint);
}

// File: contracts/base/interface/curve/ICurveDeposit_4token.sol



pragma solidity 0.5.16;

interface ICurveDeposit_4token {
  function get_virtual_price() external view returns (uint);
  function add_liquidity(
    uint256[4] calldata amounts,
    uint256 min_mint_amount
  ) external;
  function remove_liquidity_imbalance(
    uint256[4] calldata amounts,
    uint256 max_burn_amount
  ) external;
  function remove_liquidity(
    uint256 _amount,
    uint256[4] calldata amounts
  ) external;
  function exchange(
    int128 from, int128 to, uint256 _from_amount, uint256 _min_to_amount
  ) external;
  function calc_token_amount(
    uint256[4] calldata amounts,
    bool deposit
  ) external view returns(uint);
}

// File: contracts/base/interface/curve/ICurveDeposit_4token_meta.sol



pragma solidity 0.5.16;

interface ICurveDeposit_4token_meta {
  function add_liquidity(
    address pool,
    uint256[4] calldata amounts,
    uint256 min_mint_amount
  ) external;
  function remove_liquidity_imbalance(
    address pool,
    uint256[4] calldata amounts,
    uint256 max_burn_amount
  ) external;
  function remove_liquidity(
    address pool,
    uint256 _amount,
    uint256[4] calldata amounts
  ) external;
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



pragma solidity ^0.5.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
 * the optional functions; to access them see {ERC20Detailed}.
 */
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);
}

// File: @openzeppelin/contracts/utils/Address.sol



pragma solidity ^0.5.5;

/**
 * @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) {
        // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
        // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
        // for accounts without code, i.e. `keccak256('')`
        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        // solhint-disable-next-line no-inline-assembly
        assembly { codehash := extcodehash(account) }
        return (codehash != accountHash && codehash != 0x0);
    }

    /**
     * @dev Converts an `address` into `address payable`. Note that this is
     * simply a type cast: the actual underlying value is not changed.
     *
     * _Available since v2.4.0._
     */
    function toPayable(address account) internal pure returns (address payable) {
        return address(uint160(account));
    }

    /**
     * @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].
     *
     * _Available since v2.4.0._
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-call-value
        (bool success, ) = recipient.call.value(amount)("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
}

// File: contracts/base/interface/uniswap/IUniswapV2Router01.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

// File: @openzeppelin/upgrades/contracts/Initializable.sol



pragma solidity >=0.4.24 <0.7.0;


/**
 * @title Initializable
 *
 * @dev Helper contract to support initializer functions. To use it, replace
 * the constructor with a function that has the `initializer` modifier.
 * WARNING: Unlike constructors, initializer functions must be manually
 * invoked. This applies both to deploying an Initializable contract, as well
 * as extending an Initializable contract via inheritance.
 * WARNING: When used with inheritance, manual care must be taken to not invoke
 * a parent initializer twice, or ensure that all initializers are idempotent,
 * because this is not dealt with automatically as with constructors.
 */
contract Initializable {

  /**
   * @dev Indicates that the contract has been initialized.
   */
  bool private initialized;

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

  /**
   * @dev Modifier to use in the initializer function of a contract.
   */
  modifier initializer() {
    require(initializing || isConstructor() || !initialized, "Contract instance has already been initialized");

    bool isTopLevelCall = !initializing;
    if (isTopLevelCall) {
      initializing = true;
      initialized = true;
    }

    _;

    if (isTopLevelCall) {
      initializing = false;
    }
  }

  /// @dev Returns true if and only if the function is running in the constructor
  function isConstructor() private view returns (bool) {
    // extcodesize checks the size of the code stored in an address, and
    // address returns the current address. Since the code is still not
    // deployed when running a constructor, any checks on its code size will
    // yield zero, making it an effective way to detect if a contract is
    // under construction or not.
    address self = address(this);
    uint256 cs;
    assembly { cs := extcodesize(self) }
    return cs == 0;
  }

  // Reserved storage space to allow for layout changes in the future.
  uint256[50] private ______gap;
}

// File: contracts/base/upgradability/BaseUpgradeableStrategyStorage.sol



pragma solidity 0.5.16;

import "@openzeppelin/upgrades/contracts/Initializable.sol";

contract BaseUpgradeableStrategyStorage {

  bytes32 internal constant _UNDERLYING_SLOT = 0xa1709211eeccf8f4ad5b6700d52a1a9525b5f5ae1e9e5f9e5a0c2fc23c86e530;
  bytes32 internal constant _VAULT_SLOT = 0xefd7c7d9ef1040fc87e7ad11fe15f86e1d11e1df03c6d7c87f7e1f4041f08d41;

  bytes32 internal constant _REWARD_TOKEN_SLOT = 0xdae0aafd977983cb1e78d8f638900ff361dc3c48c43118ca1dd77d1af3f47bbf;
  bytes32 internal constant _REWARD_POOL_SLOT = 0x3d9bb16e77837e25cada0cf894835418b38e8e18fbec6cfd192eb344bebfa6b8;
  bytes32 internal constant _SELL_FLOOR_SLOT = 0xc403216a7704d160f6a3b5c3b149a1226a6080f0a5dd27b27d9ba9c022fa0afc;
  bytes32 internal constant _SELL_SLOT = 0x656de32df98753b07482576beb0d00a6b949ebf84c066c765f54f26725221bb6;
  bytes32 internal constant _PAUSED_INVESTING_SLOT = 0xa07a20a2d463a602c2b891eb35f244624d9068572811f63d0e094072fb54591a;

  bytes32 internal constant _PROFIT_SHARING_NUMERATOR_SLOT = 0xe3ee74fb7893020b457d8071ed1ef76ace2bf4903abd7b24d3ce312e9c72c029;
  bytes32 internal constant _PROFIT_SHARING_DENOMINATOR_SLOT = 0x0286fd414602b432a8c80a0125e9a25de9bba96da9d5068c832ff73f09208a3b;

  bytes32 internal constant _NEXT_IMPLEMENTATION_SLOT = 0x29f7fcd4fe2517c1963807a1ec27b0e45e67c60a874d5eeac7a0b1ab1bb84447;
  bytes32 internal constant _NEXT_IMPLEMENTATION_TIMESTAMP_SLOT = 0x414c5263b05428f1be1bfa98e25407cc78dd031d0d3cd2a2e3d63b488804f22e;
  bytes32 internal constant _NEXT_IMPLEMENTATION_DELAY_SLOT = 0x82b330ca72bcd6db11a26f10ce47ebcfe574a9c646bccbc6f1cd4478eae16b31;

  bytes32 internal constant _REWARD_CLAIMABLE_SLOT = 0xbc7c0d42a71b75c3129b337a259c346200f901408f273707402da4b51db3b8e7;
  bytes32 internal constant _MULTISIG_SLOT = 0x3e9de78b54c338efbc04e3a091b87dc7efb5d7024738302c548fc59fba1c34e6;

  constructor() public {
    assert(_UNDERLYING_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.underlying")) - 1));
    assert(_VAULT_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.vault")) - 1));
    assert(_REWARD_TOKEN_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.rewardToken")) - 1));
    assert(_REWARD_POOL_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.rewardPool")) - 1));
    assert(_SELL_FLOOR_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.sellFloor")) - 1));
    assert(_SELL_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.sell")) - 1));
    assert(_PAUSED_INVESTING_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.pausedInvesting")) - 1));

    assert(_PROFIT_SHARING_NUMERATOR_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.profitSharingNumerator")) - 1));
    assert(_PROFIT_SHARING_DENOMINATOR_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.profitSharingDenominator")) - 1));

    assert(_NEXT_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.nextImplementation")) - 1));
    assert(_NEXT_IMPLEMENTATION_TIMESTAMP_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.nextImplementationTimestamp")) - 1));
    assert(_NEXT_IMPLEMENTATION_DELAY_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.nextImplementationDelay")) - 1));

    assert(_REWARD_CLAIMABLE_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.rewardClaimable")) - 1));
    assert(_MULTISIG_SLOT == bytes32(uint256(keccak256("eip1967.strategyStorage.multiSig")) - 1));
  }

  function _setUnderlying(address _address) internal {
    setAddress(_UNDERLYING_SLOT, _address);
  }

  function underlying() public view returns (address) {
    return getAddress(_UNDERLYING_SLOT);
  }

  function _setRewardPool(address _address) internal {
    setAddress(_REWARD_POOL_SLOT, _address);
  }

  function rewardPool() public view returns (address) {
    return getAddress(_REWARD_POOL_SLOT);
  }

  function _setRewardToken(address _address) internal {
    setAddress(_REWARD_TOKEN_SLOT, _address);
  }

  function rewardToken() public view returns (address) {
    return getAddress(_REWARD_TOKEN_SLOT);
  }

  function _setVault(address _address) internal {
    setAddress(_VAULT_SLOT, _address);
  }

  function vault() public view returns (address) {
    return getAddress(_VAULT_SLOT);
  }

  // a flag for disabling selling for simplified emergency exit
  function _setSell(bool _value) internal {
    setBoolean(_SELL_SLOT, _value);
  }

  function sell() public view returns (bool) {
    return getBoolean(_SELL_SLOT);
  }

  function _setPausedInvesting(bool _value) internal {
    setBoolean(_PAUSED_INVESTING_SLOT, _value);
  }

  function pausedInvesting() public view returns (bool) {
    return getBoolean(_PAUSED_INVESTING_SLOT);
  }

  function _setSellFloor(uint256 _value) internal {
    setUint256(_SELL_FLOOR_SLOT, _value);
  }

  function sellFloor() public view returns (uint256) {
    return getUint256(_SELL_FLOOR_SLOT);
  }

  function _setProfitSharingNumerator(uint256 _value) internal {
    setUint256(_PROFIT_SHARING_NUMERATOR_SLOT, _value);
  }

  function profitSharingNumerator() public view returns (uint256) {
    return getUint256(_PROFIT_SHARING_NUMERATOR_SLOT);
  }

  function _setProfitSharingDenominator(uint256 _value) internal {
    setUint256(_PROFIT_SHARING_DENOMINATOR_SLOT, _value);
  }

  function profitSharingDenominator() public view returns (uint256) {
    return getUint256(_PROFIT_SHARING_DENOMINATOR_SLOT);
  }

  function allowedRewardClaimable() public view returns (bool) {
    return getBoolean(_REWARD_CLAIMABLE_SLOT);
  }

  function _setRewardClaimable(bool _value) internal {
    setBoolean(_REWARD_CLAIMABLE_SLOT, _value);
  }

  function multiSig() public view returns(address) {
    return getAddress(_MULTISIG_SLOT);
  }

  function _setMultiSig(address _address) internal {
    setAddress(_MULTISIG_SLOT, _address);
  }

  // upgradeability

  function _setNextImplementation(address _address) internal {
    setAddress(_NEXT_IMPLEMENTATION_SLOT, _address);
  }

  function nextImplementation() public view returns (address) {
    return getAddress(_NEXT_IMPLEMENTATION_SLOT);
  }

  function _setNextImplementationTimestamp(uint256 _value) internal {
    setUint256(_NEXT_IMPLEMENTATION_TIMESTAMP_SLOT, _value);
  }

  function nextImplementationTimestamp() public view returns (uint256) {
    return getUint256(_NEXT_IMPLEMENTATION_TIMESTAMP_SLOT);
  }

  function _setNextImplementationDelay(uint256 _value) internal {
    setUint256(_NEXT_IMPLEMENTATION_DELAY_SLOT, _value);
  }

  function nextImplementationDelay() public view returns (uint256) {
    return getUint256(_NEXT_IMPLEMENTATION_DELAY_SLOT);
  }

  function setBoolean(bytes32 slot, bool _value) internal {
    setUint256(slot, _value ? 1 : 0);
  }

  function getBoolean(bytes32 slot) internal view returns (bool) {
    return (getUint256(slot) == 1);
  }

  function setAddress(bytes32 slot, address _address) internal {
    // solhint-disable-next-line no-inline-assembly
    assembly {
      sstore(slot, _address)
    }
  }

  function setUint256(bytes32 slot, uint256 _value) internal {
    // solhint-disable-next-line no-inline-assembly
    assembly {
      sstore(slot, _value)
    }
  }

  function getAddress(bytes32 slot) internal view returns (address str) {
    // solhint-disable-next-line no-inline-assembly
    assembly {
      str := sload(slot)
    }
  }

  function getUint256(bytes32 slot) internal view returns (uint256 str) {
    // solhint-disable-next-line no-inline-assembly
    assembly {
      str := sload(slot)
    }
  }
}

// File: contracts/base/inheritance/ControllableInit.sol



pragma solidity 0.5.16;

import "./GovernableInit.sol";

// A clone of Governable supporting the Initializable interface and pattern
contract ControllableInit is GovernableInit {

  constructor() public {
  }

  function initialize(address _storage) public initializer {
    GovernableInit.initialize(_storage);
  }

  modifier onlyController() {
    require(Storage(_storage()).isController(msg.sender), "Not a controller");
    _;
  }

  modifier onlyControllerOrGovernance(){
    require((Storage(_storage()).isController(msg.sender) || Storage(_storage()).isGovernance(msg.sender)),
      "The caller must be controller or governance");
    _;
  }

  function controller() public view returns (address) {
    return Storage(_storage()).controller();
  }
}

// File: contracts/base/interface/IController.sol



pragma solidity 0.5.16;

interface IController {

    event SharePriceChangeLog(
      address indexed vault,
      address indexed strategy,
      uint256 oldSharePrice,
      uint256 newSharePrice,
      uint256 timestamp
    );

    // [Grey list]
    // An EOA can safely interact with the system no matter what.
    // If you're using Metamask, you're using an EOA.
    // Only smart contracts may be affected by this grey list.
    //
    // This contract will not be able to ban any EOA from the system
    // even if an EOA is being added to the greyList, he/she will still be able
    // to interact with the whole system as if nothing happened.
    // Only smart contracts will be affected by being added to the greyList.
    // This grey list is only used in Vault.sol, see the code there for reference
    function greyList(address _target) external view returns(bool);

    function addVaultAndStrategy(address _vault, address _strategy) external;
    function doHardWork(address _vault) external;

    function salvage(address _token, uint256 amount) external;
    function salvageStrategy(address _strategy, address _token, uint256 amount) external;

    function notifyFee(address _underlying, uint256 fee) external;
    function profitSharingNumerator() external view returns (uint256);
    function profitSharingDenominator() external view returns (uint256);

    function feeRewardForwarder() external view returns(address);
    function setFeeRewardForwarder(address _value) external;

    function addHardWorker(address _worker) external;
    function addToWhitelist(address _target) external;
}

// File: contracts/base/interface/IFeeRewardForwarderV6.sol



pragma solidity 0.5.16;

interface IFeeRewardForwarderV6 {
    function poolNotifyFixedTarget(address _token, uint256 _amount) external;

    function notifyFeeAndBuybackAmounts(uint256 _feeAmount, address _pool, uint256 _buybackAmount) external;
    function notifyFeeAndBuybackAmounts(address _token, uint256 _feeAmount, address _pool, uint256 _buybackAmount) external;
    function profitSharingPool() external view returns (address);
    function configureLiquidation(address[] calldata _path, bytes32[] calldata _dexes) external;
}

// File: contracts/base/interface/ILiquidator.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.5.16;

interface ILiquidator {
  event Swap(
    address indexed buyToken,
    address indexed sellToken,
    address indexed target,
    address initiator,
    uint256 amountIn,
    uint256 slippage,
    uint256 total
  );

  function swapTokenOnMultipleDEXes(
    uint256 amountIn,
    uint256 amountOutMin,
    address target,
    bytes32[] calldata dexes,
    address[] calldata path
  ) external;

  function swapTokenOnDEX(
    uint256 amountIn,
    uint256 amountOutMin,
    address target,
    bytes32 dexName,
    address[] calldata path
  ) external;

  function getAllDexes() external view returns (bytes32[] memory);
}

// File: contracts/base/interface/ILiquidatorRegistry.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.5.16;

interface ILiquidatorRegistry {

  function universalLiquidator() external view returns(address);

  function setUniversalLiquidator(address _ul) external;

  function getPath(
    bytes32 dex,
    address inputToken,
    address outputToken
  ) external view returns(address[] memory);

  function setPath(
    bytes32 dex,
    address inputToken,
    address outputToken,
    address[] calldata path
  ) external;
}

// File: contracts/base/inheritance/GovernableInit.sol



pragma solidity 0.5.16;

import "@openzeppelin/upgrades/contracts/Initializable.sol";
import "./Storage.sol";

// A clone of Governable supporting the Initializable interface and pattern
contract GovernableInit is Initializable {

  bytes32 internal constant _STORAGE_SLOT = 0xa7ec62784904ff31cbcc32d09932a58e7f1e4476e1d041995b37c917990b16dc;

  modifier onlyGovernance() {
    require(Storage(_storage()).isGovernance(msg.sender), "Not governance");
    _;
  }

  constructor() public {
    assert(_STORAGE_SLOT == bytes32(uint256(keccak256("eip1967.governableInit.storage")) - 1));
  }

  function initialize(address _store) public initializer {
    _setStorage(_store);
  }

  function _setStorage(address newStorage) private {
    bytes32 slot = _STORAGE_SLOT;
    // solhint-disable-next-line no-inline-assembly
    assembly {
      sstore(slot, newStorage)
    }
  }

  function setStorage(address _store) public onlyGovernance {
    require(_store != address(0), "new storage shouldn't be empty");
    _setStorage(_store);
  }

  function _storage() internal view returns (address str) {
    bytes32 slot = _STORAGE_SLOT;
    // solhint-disable-next-line no-inline-assembly
    assembly {
      str := sload(slot)
    }
  }

  function governance() public view returns (address) {
    return Storage(_storage()).governance();
  }
}

// File: contracts/base/inheritance/Storage.sol



pragma solidity 0.5.16;

contract Storage {

  address public governance;
  address public controller;

  constructor() public {
    governance = msg.sender;
  }

  modifier onlyGovernance() {
    require(isGovernance(msg.sender), "Not governance");
    _;
  }

  function setGovernance(address _governance) public onlyGovernance {
    require(_governance != address(0), "new governance shouldn't be empty");
    governance = _governance;
  }

  function setController(address _controller) public onlyGovernance {
    require(_controller != address(0), "new controller shouldn't be empty");
    controller = _controller;
  }

  function isGovernance(address account) public view returns (bool) {
    return account == governance;
  }

  function isController(address account) public view returns (bool) {
    return account == controller;
  }
}