MATIC Price: $0.533555 (-0.58%)
Gas: 30.9 GWei

Contract Diff Checker

Contract Name:
InitializableImmutableAdminUpgradeabilityProxy

Contract Source Code:

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {PercentageMath} from '../protocol/libraries/math/PercentageMath.sol';
import {SafeMath} from '../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IERC20} from '../dependencies/openzeppelin/contracts/IERC20.sol';
import {IERC20Detailed} from '../dependencies/openzeppelin/contracts/IERC20Detailed.sol';
import {SafeERC20} from '../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {Ownable} from '../dependencies/openzeppelin/contracts/Ownable.sol';
import {ILendingPoolAddressesProvider} from '../interfaces/ILendingPoolAddressesProvider.sol';
import {DataTypes} from '../protocol/libraries/types/DataTypes.sol';
import {IUniswapV2Router02} from '../interfaces/IUniswapV2Router02.sol';
import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
import {IERC20WithPermit} from '../interfaces/IERC20WithPermit.sol';
import {FlashLoanReceiverBase} from '../flashloan/base/FlashLoanReceiverBase.sol';
import {IBaseUniswapAdapter} from './interfaces/IBaseUniswapAdapter.sol';

/**
 * @title BaseUniswapAdapter
 * @notice Implements the logic for performing assets swaps in Uniswap V2
 * @author Aave
 **/
abstract contract BaseUniswapAdapter is FlashLoanReceiverBase, IBaseUniswapAdapter, Ownable {
  using SafeMath for uint256;
  using PercentageMath for uint256;
  using SafeERC20 for IERC20;

  // Max slippage percent allowed
  uint256 public constant override MAX_SLIPPAGE_PERCENT = 3000; // 30%
  // FLash Loan fee set in lending pool
  uint256 public constant override FLASHLOAN_PREMIUM_TOTAL = 9;
  // USD oracle asset address
  address public constant override USD_ADDRESS = 0x10F7Fc1F91Ba351f9C629c5947AD69bD03C05b96;

  address public immutable override WETH_ADDRESS;
  IPriceOracleGetter public immutable override ORACLE;
  IUniswapV2Router02 public immutable override UNISWAP_ROUTER;

  constructor(
    ILendingPoolAddressesProvider addressesProvider,
    IUniswapV2Router02 uniswapRouter,
    address wethAddress
  ) public FlashLoanReceiverBase(addressesProvider) {
    ORACLE = IPriceOracleGetter(addressesProvider.getPriceOracle());
    UNISWAP_ROUTER = uniswapRouter;
    WETH_ADDRESS = wethAddress;
  }

  /**
   * @dev Given an input asset amount, returns the maximum output amount of the other asset and the prices
   * @param amountIn Amount of reserveIn
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @return uint256 Amount out of the reserveOut
   * @return uint256 The price of out amount denominated in the reserveIn currency (18 decimals)
   * @return uint256 In amount of reserveIn value denominated in USD (8 decimals)
   * @return uint256 Out amount of reserveOut value denominated in USD (8 decimals)
   */
  function getAmountsOut(
    uint256 amountIn,
    address reserveIn,
    address reserveOut
  )
    external
    view
    override
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      address[] memory
    )
  {
    AmountCalc memory results = _getAmountsOutData(reserveIn, reserveOut, amountIn);

    return (
      results.calculatedAmount,
      results.relativePrice,
      results.amountInUsd,
      results.amountOutUsd,
      results.path
    );
  }

  /**
   * @dev Returns the minimum input asset amount required to buy the given output asset amount and the prices
   * @param amountOut Amount of reserveOut
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @return uint256 Amount in of the reserveIn
   * @return uint256 The price of in amount denominated in the reserveOut currency (18 decimals)
   * @return uint256 In amount of reserveIn value denominated in USD (8 decimals)
   * @return uint256 Out amount of reserveOut value denominated in USD (8 decimals)
   */
  function getAmountsIn(
    uint256 amountOut,
    address reserveIn,
    address reserveOut
  )
    external
    view
    override
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      address[] memory
    )
  {
    AmountCalc memory results = _getAmountsInData(reserveIn, reserveOut, amountOut);

    return (
      results.calculatedAmount,
      results.relativePrice,
      results.amountInUsd,
      results.amountOutUsd,
      results.path
    );
  }

  /**
   * @dev Swaps an exact `amountToSwap` of an asset to another
   * @param assetToSwapFrom Origin asset
   * @param assetToSwapTo Destination asset
   * @param amountToSwap Exact amount of `assetToSwapFrom` to be swapped
   * @param minAmountOut the min amount of `assetToSwapTo` to be received from the swap
   * @return the amount received from the swap
   */
  function _swapExactTokensForTokens(
    address assetToSwapFrom,
    address assetToSwapTo,
    uint256 amountToSwap,
    uint256 minAmountOut,
    bool useEthPath
  ) internal returns (uint256) {
    uint256 fromAssetDecimals = _getDecimals(assetToSwapFrom);
    uint256 toAssetDecimals = _getDecimals(assetToSwapTo);

    uint256 fromAssetPrice = _getPrice(assetToSwapFrom);
    uint256 toAssetPrice = _getPrice(assetToSwapTo);

    uint256 expectedMinAmountOut =
      amountToSwap
        .mul(fromAssetPrice.mul(10**toAssetDecimals))
        .div(toAssetPrice.mul(10**fromAssetDecimals))
        .percentMul(PercentageMath.PERCENTAGE_FACTOR.sub(MAX_SLIPPAGE_PERCENT));

    require(expectedMinAmountOut < minAmountOut, 'minAmountOut exceed max slippage');

    // Approves the transfer for the swap. Approves for 0 first to comply with tokens that implement the anti frontrunning approval fix.
    IERC20(assetToSwapFrom).safeApprove(address(UNISWAP_ROUTER), 0);
    IERC20(assetToSwapFrom).safeApprove(address(UNISWAP_ROUTER), amountToSwap);

    address[] memory path;
    if (useEthPath) {
      path = new address[](3);
      path[0] = assetToSwapFrom;
      path[1] = WETH_ADDRESS;
      path[2] = assetToSwapTo;
    } else {
      path = new address[](2);
      path[0] = assetToSwapFrom;
      path[1] = assetToSwapTo;
    }
    uint256[] memory amounts =
      UNISWAP_ROUTER.swapExactTokensForTokens(
        amountToSwap,
        minAmountOut,
        path,
        address(this),
        block.timestamp
      );

    emit Swapped(assetToSwapFrom, assetToSwapTo, amounts[0], amounts[amounts.length - 1]);

    return amounts[amounts.length - 1];
  }

  /**
   * @dev Receive an exact amount `amountToReceive` of `assetToSwapTo` tokens for as few `assetToSwapFrom` tokens as
   * possible.
   * @param assetToSwapFrom Origin asset
   * @param assetToSwapTo Destination asset
   * @param maxAmountToSwap Max amount of `assetToSwapFrom` allowed to be swapped
   * @param amountToReceive Exact amount of `assetToSwapTo` to receive
   * @return the amount swapped
   */
  function _swapTokensForExactTokens(
    address assetToSwapFrom,
    address assetToSwapTo,
    uint256 maxAmountToSwap,
    uint256 amountToReceive,
    bool useEthPath
  ) internal returns (uint256) {
    uint256 fromAssetDecimals = _getDecimals(assetToSwapFrom);
    uint256 toAssetDecimals = _getDecimals(assetToSwapTo);

    uint256 fromAssetPrice = _getPrice(assetToSwapFrom);
    uint256 toAssetPrice = _getPrice(assetToSwapTo);

    uint256 expectedMaxAmountToSwap =
      amountToReceive
        .mul(toAssetPrice.mul(10**fromAssetDecimals))
        .div(fromAssetPrice.mul(10**toAssetDecimals))
        .percentMul(PercentageMath.PERCENTAGE_FACTOR.add(MAX_SLIPPAGE_PERCENT));

    require(maxAmountToSwap < expectedMaxAmountToSwap, 'maxAmountToSwap exceed max slippage');

    // Approves the transfer for the swap. Approves for 0 first to comply with tokens that implement the anti frontrunning approval fix.
    IERC20(assetToSwapFrom).safeApprove(address(UNISWAP_ROUTER), 0);
    IERC20(assetToSwapFrom).safeApprove(address(UNISWAP_ROUTER), maxAmountToSwap);

    address[] memory path;
    if (useEthPath) {
      path = new address[](3);
      path[0] = assetToSwapFrom;
      path[1] = WETH_ADDRESS;
      path[2] = assetToSwapTo;
    } else {
      path = new address[](2);
      path[0] = assetToSwapFrom;
      path[1] = assetToSwapTo;
    }

    uint256[] memory amounts =
      UNISWAP_ROUTER.swapTokensForExactTokens(
        amountToReceive,
        maxAmountToSwap,
        path,
        address(this),
        block.timestamp
      );

    emit Swapped(assetToSwapFrom, assetToSwapTo, amounts[0], amounts[amounts.length - 1]);

    return amounts[0];
  }

  /**
   * @dev Get the price of the asset from the oracle denominated in eth
   * @param asset address
   * @return eth price for the asset
   */
  function _getPrice(address asset) internal view returns (uint256) {
    return ORACLE.getAssetPrice(asset);
  }

  /**
   * @dev Get the decimals of an asset
   * @return number of decimals of the asset
   */
  function _getDecimals(address asset) internal view returns (uint256) {
    return IERC20Detailed(asset).decimals();
  }

  /**
   * @dev Get the aToken associated to the asset
   * @return address of the aToken
   */
  function _getReserveData(address asset) internal view returns (DataTypes.ReserveData memory) {
    return LENDING_POOL.getReserveData(asset);
  }

  /**
   * @dev Pull the ATokens from the user
   * @param reserve address of the asset
   * @param reserveAToken address of the aToken of the reserve
   * @param user address
   * @param amount of tokens to be transferred to the contract
   * @param permitSignature struct containing the permit signature
   */
  function _pullAToken(
    address reserve,
    address reserveAToken,
    address user,
    uint256 amount,
    PermitSignature memory permitSignature
  ) internal {
    if (_usePermit(permitSignature)) {
      IERC20WithPermit(reserveAToken).permit(
        user,
        address(this),
        permitSignature.amount,
        permitSignature.deadline,
        permitSignature.v,
        permitSignature.r,
        permitSignature.s
      );
    }

    // transfer from user to adapter
    IERC20(reserveAToken).safeTransferFrom(user, address(this), amount);

    // withdraw reserve
    LENDING_POOL.withdraw(reserve, amount, address(this));
  }

  /**
   * @dev Tells if the permit method should be called by inspecting if there is a valid signature.
   * If signature params are set to 0, then permit won't be called.
   * @param signature struct containing the permit signature
   * @return whether or not permit should be called
   */
  function _usePermit(PermitSignature memory signature) internal pure returns (bool) {
    return
      !(uint256(signature.deadline) == uint256(signature.v) && uint256(signature.deadline) == 0);
  }

  /**
   * @dev Calculates the value denominated in USD
   * @param reserve Address of the reserve
   * @param amount Amount of the reserve
   * @param decimals Decimals of the reserve
   * @return whether or not permit should be called
   */
  function _calcUsdValue(
    address reserve,
    uint256 amount,
    uint256 decimals
  ) internal view returns (uint256) {
    uint256 ethUsdPrice = _getPrice(USD_ADDRESS);
    uint256 reservePrice = _getPrice(reserve);

    return amount.mul(reservePrice).div(10**decimals).mul(ethUsdPrice).div(10**18);
  }

  /**
   * @dev Given an input asset amount, returns the maximum output amount of the other asset
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @param amountIn Amount of reserveIn
   * @return Struct containing the following information:
   *   uint256 Amount out of the reserveOut
   *   uint256 The price of out amount denominated in the reserveIn currency (18 decimals)
   *   uint256 In amount of reserveIn value denominated in USD (8 decimals)
   *   uint256 Out amount of reserveOut value denominated in USD (8 decimals)
   */
  function _getAmountsOutData(
    address reserveIn,
    address reserveOut,
    uint256 amountIn
  ) internal view returns (AmountCalc memory) {
    // Subtract flash loan fee
    uint256 finalAmountIn = amountIn.sub(amountIn.mul(FLASHLOAN_PREMIUM_TOTAL).div(10000));

    if (reserveIn == reserveOut) {
      uint256 reserveDecimals = _getDecimals(reserveIn);
      address[] memory path = new address[](1);
      path[0] = reserveIn;

      return
        AmountCalc(
          finalAmountIn,
          finalAmountIn.mul(10**18).div(amountIn),
          _calcUsdValue(reserveIn, amountIn, reserveDecimals),
          _calcUsdValue(reserveIn, finalAmountIn, reserveDecimals),
          path
        );
    }

    address[] memory simplePath = new address[](2);
    simplePath[0] = reserveIn;
    simplePath[1] = reserveOut;

    uint256[] memory amountsWithoutWeth;
    uint256[] memory amountsWithWeth;

    address[] memory pathWithWeth = new address[](3);
    if (reserveIn != WETH_ADDRESS && reserveOut != WETH_ADDRESS) {
      pathWithWeth[0] = reserveIn;
      pathWithWeth[1] = WETH_ADDRESS;
      pathWithWeth[2] = reserveOut;

      try UNISWAP_ROUTER.getAmountsOut(finalAmountIn, pathWithWeth) returns (
        uint256[] memory resultsWithWeth
      ) {
        amountsWithWeth = resultsWithWeth;
      } catch {
        amountsWithWeth = new uint256[](3);
      }
    } else {
      amountsWithWeth = new uint256[](3);
    }

    uint256 bestAmountOut;
    try UNISWAP_ROUTER.getAmountsOut(finalAmountIn, simplePath) returns (
      uint256[] memory resultAmounts
    ) {
      amountsWithoutWeth = resultAmounts;

      bestAmountOut = (amountsWithWeth[2] > amountsWithoutWeth[1])
        ? amountsWithWeth[2]
        : amountsWithoutWeth[1];
    } catch {
      amountsWithoutWeth = new uint256[](2);
      bestAmountOut = amountsWithWeth[2];
    }

    uint256 reserveInDecimals = _getDecimals(reserveIn);
    uint256 reserveOutDecimals = _getDecimals(reserveOut);

    uint256 outPerInPrice =
      finalAmountIn.mul(10**18).mul(10**reserveOutDecimals).div(
        bestAmountOut.mul(10**reserveInDecimals)
      );

    return
      AmountCalc(
        bestAmountOut,
        outPerInPrice,
        _calcUsdValue(reserveIn, amountIn, reserveInDecimals),
        _calcUsdValue(reserveOut, bestAmountOut, reserveOutDecimals),
        (bestAmountOut == 0) ? new address[](2) : (bestAmountOut == amountsWithoutWeth[1])
          ? simplePath
          : pathWithWeth
      );
  }

  /**
   * @dev Returns the minimum input asset amount required to buy the given output asset amount
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @param amountOut Amount of reserveOut
   * @return Struct containing the following information:
   *   uint256 Amount in of the reserveIn
   *   uint256 The price of in amount denominated in the reserveOut currency (18 decimals)
   *   uint256 In amount of reserveIn value denominated in USD (8 decimals)
   *   uint256 Out amount of reserveOut value denominated in USD (8 decimals)
   */
  function _getAmountsInData(
    address reserveIn,
    address reserveOut,
    uint256 amountOut
  ) internal view returns (AmountCalc memory) {
    if (reserveIn == reserveOut) {
      // Add flash loan fee
      uint256 amountIn = amountOut.add(amountOut.mul(FLASHLOAN_PREMIUM_TOTAL).div(10000));
      uint256 reserveDecimals = _getDecimals(reserveIn);
      address[] memory path = new address[](1);
      path[0] = reserveIn;

      return
        AmountCalc(
          amountIn,
          amountOut.mul(10**18).div(amountIn),
          _calcUsdValue(reserveIn, amountIn, reserveDecimals),
          _calcUsdValue(reserveIn, amountOut, reserveDecimals),
          path
        );
    }

    (uint256[] memory amounts, address[] memory path) =
      _getAmountsInAndPath(reserveIn, reserveOut, amountOut);

    // Add flash loan fee
    uint256 finalAmountIn = amounts[0].add(amounts[0].mul(FLASHLOAN_PREMIUM_TOTAL).div(10000));

    uint256 reserveInDecimals = _getDecimals(reserveIn);
    uint256 reserveOutDecimals = _getDecimals(reserveOut);

    uint256 inPerOutPrice =
      amountOut.mul(10**18).mul(10**reserveInDecimals).div(
        finalAmountIn.mul(10**reserveOutDecimals)
      );

    return
      AmountCalc(
        finalAmountIn,
        inPerOutPrice,
        _calcUsdValue(reserveIn, finalAmountIn, reserveInDecimals),
        _calcUsdValue(reserveOut, amountOut, reserveOutDecimals),
        path
      );
  }

  /**
   * @dev Calculates the input asset amount required to buy the given output asset amount
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @param amountOut Amount of reserveOut
   * @return uint256[] amounts Array containing the amountIn and amountOut for a swap
   */
  function _getAmountsInAndPath(
    address reserveIn,
    address reserveOut,
    uint256 amountOut
  ) internal view returns (uint256[] memory, address[] memory) {
    address[] memory simplePath = new address[](2);
    simplePath[0] = reserveIn;
    simplePath[1] = reserveOut;

    uint256[] memory amountsWithoutWeth;
    uint256[] memory amountsWithWeth;
    address[] memory pathWithWeth = new address[](3);

    if (reserveIn != WETH_ADDRESS && reserveOut != WETH_ADDRESS) {
      pathWithWeth[0] = reserveIn;
      pathWithWeth[1] = WETH_ADDRESS;
      pathWithWeth[2] = reserveOut;

      try UNISWAP_ROUTER.getAmountsIn(amountOut, pathWithWeth) returns (
        uint256[] memory resultsWithWeth
      ) {
        amountsWithWeth = resultsWithWeth;
      } catch {
        amountsWithWeth = new uint256[](3);
      }
    } else {
      amountsWithWeth = new uint256[](3);
    }

    try UNISWAP_ROUTER.getAmountsIn(amountOut, simplePath) returns (
      uint256[] memory resultAmounts
    ) {
      amountsWithoutWeth = resultAmounts;

      return
        (amountsWithWeth[0] < amountsWithoutWeth[0] && amountsWithWeth[0] != 0)
          ? (amountsWithWeth, pathWithWeth)
          : (amountsWithoutWeth, simplePath);
    } catch {
      return (amountsWithWeth, pathWithWeth);
    }
  }

  /**
   * @dev Calculates the input asset amount required to buy the given output asset amount
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @param amountOut Amount of reserveOut
   * @return uint256[] amounts Array containing the amountIn and amountOut for a swap
   */
  function _getAmountsIn(
    address reserveIn,
    address reserveOut,
    uint256 amountOut,
    bool useEthPath
  ) internal view returns (uint256[] memory) {
    address[] memory path;

    if (useEthPath) {
      path = new address[](3);
      path[0] = reserveIn;
      path[1] = WETH_ADDRESS;
      path[2] = reserveOut;
    } else {
      path = new address[](2);
      path[0] = reserveIn;
      path[1] = reserveOut;
    }

    return UNISWAP_ROUTER.getAmountsIn(amountOut, path);
  }

  /**
   * @dev Emergency rescue for token stucked on this contract, as failsafe mechanism
   * - Funds should never remain in this contract more time than during transactions
   * - Only callable by the owner
   **/
  function rescueTokens(IERC20 token) external onlyOwner {
    token.transfer(owner(), token.balanceOf(address(this)));
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {Errors} from '../helpers/Errors.sol';

/**
 * @title PercentageMath library
 * @author Aave
 * @notice Provides functions to perform percentage calculations
 * @dev Percentages are defined by default with 2 decimals of precision (100.00). The precision is indicated by PERCENTAGE_FACTOR
 * @dev Operations are rounded half up
 **/

library PercentageMath {
  uint256 constant PERCENTAGE_FACTOR = 1e4; //percentage plus two decimals
  uint256 constant HALF_PERCENT = PERCENTAGE_FACTOR / 2;

  /**
   * @dev Executes a percentage multiplication
   * @param value The value of which the percentage needs to be calculated
   * @param percentage The percentage of the value to be calculated
   * @return The percentage of value
   **/
  function percentMul(uint256 value, uint256 percentage) internal pure returns (uint256) {
    if (value == 0 || percentage == 0) {
      return 0;
    }

    require(
      value <= (type(uint256).max - HALF_PERCENT) / percentage,
      Errors.MATH_MULTIPLICATION_OVERFLOW
    );

    return (value * percentage + HALF_PERCENT) / PERCENTAGE_FACTOR;
  }

  /**
   * @dev Executes a percentage division
   * @param value The value of which the percentage needs to be calculated
   * @param percentage The percentage of the value to be calculated
   * @return The value divided the percentage
   **/
  function percentDiv(uint256 value, uint256 percentage) internal pure returns (uint256) {
    require(percentage != 0, Errors.MATH_DIVISION_BY_ZERO);
    uint256 halfPercentage = percentage / 2;

    require(
      value <= (type(uint256).max - halfPercentage) / PERCENTAGE_FACTOR,
      Errors.MATH_MULTIPLICATION_OVERFLOW
    );

    return (value * PERCENTAGE_FACTOR + halfPercentage) / percentage;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @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.
   */
  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.
   */
  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.
   */
  function mod(
    uint256 a,
    uint256 b,
    string memory errorMessage
  ) internal pure returns (uint256) {
    require(b != 0, errorMessage);
    return a % b;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

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

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

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

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

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

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

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

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

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IERC20} from './IERC20.sol';

interface IERC20Detailed is IERC20 {
  function name() external view returns (string memory);

  function symbol() external view returns (string memory);

  function decimals() external view returns (uint8);
}

// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import {IERC20} from './IERC20.sol';
import {SafeMath} from './SafeMath.sol';
import {Address} from './Address.sol';

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

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

import './Context.sol';

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
contract Ownable is Context {
  address private _owner;

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

  /**
   * @dev Initializes the contract setting the deployer as the initial owner.
   */
  constructor() internal {
    address msgSender = _msgSender();
    _owner = msgSender;
    emit OwnershipTransferred(address(0), msgSender);
  }

  /**
   * @dev Returns the address of the current owner.
   */
  function owner() public view returns (address) {
    return _owner;
  }

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(_owner == _msgSender(), 'Ownable: caller is not the owner');
    _;
  }

  /**
   * @dev Leaves the contract without owner. It will not be possible to call
   * `onlyOwner` functions anymore. Can only be called by the current owner.
   *
   * NOTE: Renouncing ownership will leave the contract without an owner,
   * thereby removing any functionality that is only available to the owner.
   */
  function renounceOwnership() public virtual onlyOwner {
    emit OwnershipTransferred(_owner, address(0));
    _owner = address(0);
  }

  /**
   * @dev Transfers ownership of the contract to a new account (`newOwner`).
   * Can only be called by the current owner.
   */
  function transferOwnership(address newOwner) public virtual onlyOwner {
    require(newOwner != address(0), 'Ownable: new owner is the zero address');
    emit OwnershipTransferred(_owner, newOwner);
    _owner = newOwner;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title LendingPoolAddressesProvider contract
 * @dev Main registry of addresses part of or connected to the protocol, including permissioned roles
 * - Acting also as factory of proxies and admin of those, so with right to change its implementations
 * - Owned by the Aave Governance
 * @author Aave
 **/
interface ILendingPoolAddressesProvider {
  event MarketIdSet(string newMarketId);
  event LendingPoolUpdated(address indexed newAddress);
  event ConfigurationAdminUpdated(address indexed newAddress);
  event EmergencyAdminUpdated(address indexed newAddress);
  event LendingPoolConfiguratorUpdated(address indexed newAddress);
  event LendingPoolCollateralManagerUpdated(address indexed newAddress);
  event PriceOracleUpdated(address indexed newAddress);
  event LendingRateOracleUpdated(address indexed newAddress);
  event ProxyCreated(bytes32 id, address indexed newAddress);
  event AddressSet(bytes32 id, address indexed newAddress, bool hasProxy);

  function getMarketId() external view returns (string memory);

  function setMarketId(string calldata marketId) external;

  function setAddress(bytes32 id, address newAddress) external;

  function setAddressAsProxy(bytes32 id, address impl) external;

  function getAddress(bytes32 id) external view returns (address);

  function getLendingPool() external view returns (address);

  function setLendingPoolImpl(address pool) external;

  function getLendingPoolConfigurator() external view returns (address);

  function setLendingPoolConfiguratorImpl(address configurator) external;

  function getLendingPoolCollateralManager() external view returns (address);

  function setLendingPoolCollateralManager(address manager) external;

  function getPoolAdmin() external view returns (address);

  function setPoolAdmin(address admin) external;

  function getEmergencyAdmin() external view returns (address);

  function setEmergencyAdmin(address admin) external;

  function getPriceOracle() external view returns (address);

  function setPriceOracle(address priceOracle) external;

  function getLendingRateOracle() external view returns (address);

  function setLendingRateOracle(address lendingRateOracle) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

library DataTypes {
  // refer to the whitepaper, section 1.1 basic concepts for a formal description of these properties.
  struct ReserveData {
    //stores the reserve configuration
    ReserveConfigurationMap configuration;
    //the liquidity index. Expressed in ray
    uint128 liquidityIndex;
    //variable borrow index. Expressed in ray
    uint128 variableBorrowIndex;
    //the current supply rate. Expressed in ray
    uint128 currentLiquidityRate;
    //the current variable borrow rate. Expressed in ray
    uint128 currentVariableBorrowRate;
    //the current stable borrow rate. Expressed in ray
    uint128 currentStableBorrowRate;
    uint40 lastUpdateTimestamp;
    //tokens addresses
    address aTokenAddress;
    address stableDebtTokenAddress;
    address variableDebtTokenAddress;
    //address of the interest rate strategy
    address interestRateStrategyAddress;
    //the id of the reserve. Represents the position in the list of the active reserves
    uint8 id;
  }

  struct ReserveConfigurationMap {
    //bit 0-15: LTV
    //bit 16-31: Liq. threshold
    //bit 32-47: Liq. bonus
    //bit 48-55: Decimals
    //bit 56: Reserve is active
    //bit 57: reserve is frozen
    //bit 58: borrowing is enabled
    //bit 59: stable rate borrowing enabled
    //bit 60-63: reserved
    //bit 64-79: reserve factor
    uint256 data;
  }

  struct UserConfigurationMap {
    uint256 data;
  }

  enum InterestRateMode {NONE, STABLE, VARIABLE}
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

interface IUniswapV2Router02 {
  function swapExactTokensForTokens(
    uint256 amountIn,
    uint256 amountOutMin,
    address[] calldata path,
    address to,
    uint256 deadline
  ) external returns (uint256[] memory amounts);

  function swapTokensForExactTokens(
    uint256 amountOut,
    uint256 amountInMax,
    address[] calldata path,
    address to,
    uint256 deadline
  ) external returns (uint256[] memory amounts);

  function getAmountsOut(uint256 amountIn, address[] calldata path)
    external
    view
    returns (uint256[] memory amounts);

  function getAmountsIn(uint256 amountOut, address[] calldata path)
    external
    view
    returns (uint256[] memory amounts);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title IPriceOracleGetter interface
 * @notice Interface for the Aave price oracle.
 **/

interface IPriceOracleGetter {
  /**
   * @dev returns the asset price in ETH
   * @param asset the address of the asset
   * @return the ETH price of the asset
   **/
  function getAssetPrice(address asset) external view returns (uint256);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IERC20} from '../dependencies/openzeppelin/contracts/IERC20.sol';

interface IERC20WithPermit is IERC20 {
  function permit(
    address owner,
    address spender,
    uint256 value,
    uint256 deadline,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {SafeMath} from '../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IERC20} from '../../dependencies/openzeppelin/contracts/IERC20.sol';
import {SafeERC20} from '../../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {IFlashLoanReceiver} from '../interfaces/IFlashLoanReceiver.sol';
import {ILendingPoolAddressesProvider} from '../../interfaces/ILendingPoolAddressesProvider.sol';
import {ILendingPool} from '../../interfaces/ILendingPool.sol';

abstract contract FlashLoanReceiverBase is IFlashLoanReceiver {
  using SafeERC20 for IERC20;
  using SafeMath for uint256;

  ILendingPoolAddressesProvider public immutable override ADDRESSES_PROVIDER;
  ILendingPool public immutable override LENDING_POOL;

  constructor(ILendingPoolAddressesProvider provider) public {
    ADDRESSES_PROVIDER = provider;
    LENDING_POOL = ILendingPool(provider.getLendingPool());
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
import {IUniswapV2Router02} from '../../interfaces/IUniswapV2Router02.sol';

interface IBaseUniswapAdapter {
  event Swapped(address fromAsset, address toAsset, uint256 fromAmount, uint256 receivedAmount);

  struct PermitSignature {
    uint256 amount;
    uint256 deadline;
    uint8 v;
    bytes32 r;
    bytes32 s;
  }

  struct AmountCalc {
    uint256 calculatedAmount;
    uint256 relativePrice;
    uint256 amountInUsd;
    uint256 amountOutUsd;
    address[] path;
  }

  function WETH_ADDRESS() external returns (address);

  function MAX_SLIPPAGE_PERCENT() external returns (uint256);

  function FLASHLOAN_PREMIUM_TOTAL() external returns (uint256);

  function USD_ADDRESS() external returns (address);

  function ORACLE() external returns (IPriceOracleGetter);

  function UNISWAP_ROUTER() external returns (IUniswapV2Router02);

  /**
   * @dev Given an input asset amount, returns the maximum output amount of the other asset and the prices
   * @param amountIn Amount of reserveIn
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @return uint256 Amount out of the reserveOut
   * @return uint256 The price of out amount denominated in the reserveIn currency (18 decimals)
   * @return uint256 In amount of reserveIn value denominated in USD (8 decimals)
   * @return uint256 Out amount of reserveOut value denominated in USD (8 decimals)
   * @return address[] The exchange path
   */
  function getAmountsOut(
    uint256 amountIn,
    address reserveIn,
    address reserveOut
  )
    external
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      address[] memory
    );

  /**
   * @dev Returns the minimum input asset amount required to buy the given output asset amount and the prices
   * @param amountOut Amount of reserveOut
   * @param reserveIn Address of the asset to be swap from
   * @param reserveOut Address of the asset to be swap to
   * @return uint256 Amount in of the reserveIn
   * @return uint256 The price of in amount denominated in the reserveOut currency (18 decimals)
   * @return uint256 In amount of reserveIn value denominated in USD (8 decimals)
   * @return uint256 Out amount of reserveOut value denominated in USD (8 decimals)
   * @return address[] The exchange path
   */
  function getAmountsIn(
    uint256 amountOut,
    address reserveIn,
    address reserveOut
  )
    external
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      address[] memory
    );
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title Errors library
 * @author Aave
 * @notice Defines the error messages emitted by the different contracts of the Aave protocol
 * @dev Error messages prefix glossary:
 *  - VL = ValidationLogic
 *  - MATH = Math libraries
 *  - CT = Common errors between tokens (AToken, VariableDebtToken and StableDebtToken)
 *  - AT = AToken
 *  - SDT = StableDebtToken
 *  - VDT = VariableDebtToken
 *  - LP = LendingPool
 *  - LPAPR = LendingPoolAddressesProviderRegistry
 *  - LPC = LendingPoolConfiguration
 *  - RL = ReserveLogic
 *  - LPCM = LendingPoolCollateralManager
 *  - P = Pausable
 */
library Errors {
  //common errors
  string public constant CALLER_NOT_POOL_ADMIN = '33'; // 'The caller must be the pool admin'
  string public constant BORROW_ALLOWANCE_NOT_ENOUGH = '59'; // User borrows on behalf, but allowance are too small

  //contract specific errors
  string public constant VL_INVALID_AMOUNT = '1'; // 'Amount must be greater than 0'
  string public constant VL_NO_ACTIVE_RESERVE = '2'; // 'Action requires an active reserve'
  string public constant VL_RESERVE_FROZEN = '3'; // 'Action cannot be performed because the reserve is frozen'
  string public constant VL_CURRENT_AVAILABLE_LIQUIDITY_NOT_ENOUGH = '4'; // 'The current liquidity is not enough'
  string public constant VL_NOT_ENOUGH_AVAILABLE_USER_BALANCE = '5'; // 'User cannot withdraw more than the available balance'
  string public constant VL_TRANSFER_NOT_ALLOWED = '6'; // 'Transfer cannot be allowed.'
  string public constant VL_BORROWING_NOT_ENABLED = '7'; // 'Borrowing is not enabled'
  string public constant VL_INVALID_INTEREST_RATE_MODE_SELECTED = '8'; // 'Invalid interest rate mode selected'
  string public constant VL_COLLATERAL_BALANCE_IS_0 = '9'; // 'The collateral balance is 0'
  string public constant VL_HEALTH_FACTOR_LOWER_THAN_LIQUIDATION_THRESHOLD = '10'; // 'Health factor is lesser than the liquidation threshold'
  string public constant VL_COLLATERAL_CANNOT_COVER_NEW_BORROW = '11'; // 'There is not enough collateral to cover a new borrow'
  string public constant VL_STABLE_BORROWING_NOT_ENABLED = '12'; // stable borrowing not enabled
  string public constant VL_COLLATERAL_SAME_AS_BORROWING_CURRENCY = '13'; // collateral is (mostly) the same currency that is being borrowed
  string public constant VL_AMOUNT_BIGGER_THAN_MAX_LOAN_SIZE_STABLE = '14'; // 'The requested amount is greater than the max loan size in stable rate mode
  string public constant VL_NO_DEBT_OF_SELECTED_TYPE = '15'; // 'for repayment of stable debt, the user needs to have stable debt, otherwise, he needs to have variable debt'
  string public constant VL_NO_EXPLICIT_AMOUNT_TO_REPAY_ON_BEHALF = '16'; // 'To repay on behalf of an user an explicit amount to repay is needed'
  string public constant VL_NO_STABLE_RATE_LOAN_IN_RESERVE = '17'; // 'User does not have a stable rate loan in progress on this reserve'
  string public constant VL_NO_VARIABLE_RATE_LOAN_IN_RESERVE = '18'; // 'User does not have a variable rate loan in progress on this reserve'
  string public constant VL_UNDERLYING_BALANCE_NOT_GREATER_THAN_0 = '19'; // 'The underlying balance needs to be greater than 0'
  string public constant VL_DEPOSIT_ALREADY_IN_USE = '20'; // 'User deposit is already being used as collateral'
  string public constant LP_NOT_ENOUGH_STABLE_BORROW_BALANCE = '21'; // 'User does not have any stable rate loan for this reserve'
  string public constant LP_INTEREST_RATE_REBALANCE_CONDITIONS_NOT_MET = '22'; // 'Interest rate rebalance conditions were not met'
  string public constant LP_LIQUIDATION_CALL_FAILED = '23'; // 'Liquidation call failed'
  string public constant LP_NOT_ENOUGH_LIQUIDITY_TO_BORROW = '24'; // 'There is not enough liquidity available to borrow'
  string public constant LP_REQUESTED_AMOUNT_TOO_SMALL = '25'; // 'The requested amount is too small for a FlashLoan.'
  string public constant LP_INCONSISTENT_PROTOCOL_ACTUAL_BALANCE = '26'; // 'The actual balance of the protocol is inconsistent'
  string public constant LP_CALLER_NOT_LENDING_POOL_CONFIGURATOR = '27'; // 'The caller of the function is not the lending pool configurator'
  string public constant LP_INCONSISTENT_FLASHLOAN_PARAMS = '28';
  string public constant CT_CALLER_MUST_BE_LENDING_POOL = '29'; // 'The caller of this function must be a lending pool'
  string public constant CT_CANNOT_GIVE_ALLOWANCE_TO_HIMSELF = '30'; // 'User cannot give allowance to himself'
  string public constant CT_TRANSFER_AMOUNT_NOT_GT_0 = '31'; // 'Transferred amount needs to be greater than zero'
  string public constant RL_RESERVE_ALREADY_INITIALIZED = '32'; // 'Reserve has already been initialized'
  string public constant LPC_RESERVE_LIQUIDITY_NOT_0 = '34'; // 'The liquidity of the reserve needs to be 0'
  string public constant LPC_INVALID_ATOKEN_POOL_ADDRESS = '35'; // 'The liquidity of the reserve needs to be 0'
  string public constant LPC_INVALID_STABLE_DEBT_TOKEN_POOL_ADDRESS = '36'; // 'The liquidity of the reserve needs to be 0'
  string public constant LPC_INVALID_VARIABLE_DEBT_TOKEN_POOL_ADDRESS = '37'; // 'The liquidity of the reserve needs to be 0'
  string public constant LPC_INVALID_STABLE_DEBT_TOKEN_UNDERLYING_ADDRESS = '38'; // 'The liquidity of the reserve needs to be 0'
  string public constant LPC_INVALID_VARIABLE_DEBT_TOKEN_UNDERLYING_ADDRESS = '39'; // 'The liquidity of the reserve needs to be 0'
  string public constant LPC_INVALID_ADDRESSES_PROVIDER_ID = '40'; // 'The liquidity of the reserve needs to be 0'
  string public constant LPC_INVALID_CONFIGURATION = '75'; // 'Invalid risk parameters for the reserve'
  string public constant LPC_CALLER_NOT_EMERGENCY_ADMIN = '76'; // 'The caller must be the emergency admin'
  string public constant LPAPR_PROVIDER_NOT_REGISTERED = '41'; // 'Provider is not registered'
  string public constant LPCM_HEALTH_FACTOR_NOT_BELOW_THRESHOLD = '42'; // 'Health factor is not below the threshold'
  string public constant LPCM_COLLATERAL_CANNOT_BE_LIQUIDATED = '43'; // 'The collateral chosen cannot be liquidated'
  string public constant LPCM_SPECIFIED_CURRENCY_NOT_BORROWED_BY_USER = '44'; // 'User did not borrow the specified currency'
  string public constant LPCM_NOT_ENOUGH_LIQUIDITY_TO_LIQUIDATE = '45'; // "There isn't enough liquidity available to liquidate"
  string public constant LPCM_NO_ERRORS = '46'; // 'No errors'
  string public constant LP_INVALID_FLASHLOAN_MODE = '47'; //Invalid flashloan mode selected
  string public constant MATH_MULTIPLICATION_OVERFLOW = '48';
  string public constant MATH_ADDITION_OVERFLOW = '49';
  string public constant MATH_DIVISION_BY_ZERO = '50';
  string public constant RL_LIQUIDITY_INDEX_OVERFLOW = '51'; //  Liquidity index overflows uint128
  string public constant RL_VARIABLE_BORROW_INDEX_OVERFLOW = '52'; //  Variable borrow index overflows uint128
  string public constant RL_LIQUIDITY_RATE_OVERFLOW = '53'; //  Liquidity rate overflows uint128
  string public constant RL_VARIABLE_BORROW_RATE_OVERFLOW = '54'; //  Variable borrow rate overflows uint128
  string public constant RL_STABLE_BORROW_RATE_OVERFLOW = '55'; //  Stable borrow rate overflows uint128
  string public constant CT_INVALID_MINT_AMOUNT = '56'; //invalid amount to mint
  string public constant LP_FAILED_REPAY_WITH_COLLATERAL = '57';
  string public constant CT_INVALID_BURN_AMOUNT = '58'; //invalid amount to burn
  string public constant LP_FAILED_COLLATERAL_SWAP = '60';
  string public constant LP_INVALID_EQUAL_ASSETS_TO_SWAP = '61';
  string public constant LP_REENTRANCY_NOT_ALLOWED = '62';
  string public constant LP_CALLER_MUST_BE_AN_ATOKEN = '63';
  string public constant LP_IS_PAUSED = '64'; // 'Pool is paused'
  string public constant LP_NO_MORE_RESERVES_ALLOWED = '65';
  string public constant LP_INVALID_FLASH_LOAN_EXECUTOR_RETURN = '66';
  string public constant RC_INVALID_LTV = '67';
  string public constant RC_INVALID_LIQ_THRESHOLD = '68';
  string public constant RC_INVALID_LIQ_BONUS = '69';
  string public constant RC_INVALID_DECIMALS = '70';
  string public constant RC_INVALID_RESERVE_FACTOR = '71';
  string public constant LPAPR_INVALID_ADDRESSES_PROVIDER_ID = '72';
  string public constant VL_INCONSISTENT_FLASHLOAN_PARAMS = '73';
  string public constant LP_INCONSISTENT_PARAMS_LENGTH = '74';
  string public constant UL_INVALID_INDEX = '77';
  string public constant LP_NOT_CONTRACT = '78';
  string public constant SDT_STABLE_DEBT_OVERFLOW = '79';
  string public constant SDT_BURN_EXCEEDS_BALANCE = '80';

  enum CollateralManagerErrors {
    NO_ERROR,
    NO_COLLATERAL_AVAILABLE,
    COLLATERAL_CANNOT_BE_LIQUIDATED,
    CURRRENCY_NOT_BORROWED,
    HEALTH_FACTOR_ABOVE_THRESHOLD,
    NOT_ENOUGH_LIQUIDITY,
    NO_ACTIVE_RESERVE,
    HEALTH_FACTOR_LOWER_THAN_LIQUIDATION_THRESHOLD,
    INVALID_EQUAL_ASSETS_TO_SWAP,
    FROZEN_RESERVE
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @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 Replacement for Solidity's `transfer`: sends `amount` wei to
   * `recipient`, forwarding all available gas and reverting on errors.
   *
   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
   * of certain opcodes, possibly making contracts go over the 2300 gas limit
   * imposed by `transfer`, making them unable to receive funds via
   * `transfer`. {sendValue} removes this limitation.
   *
   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
   *
   * IMPORTANT: because control is transferred to `recipient`, care must be
   * taken to not create reentrancy vulnerabilities. Consider using
   * {ReentrancyGuard} or the
   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
   */
  function sendValue(address payable recipient, uint256 amount) internal {
    require(address(this).balance >= amount, 'Address: insufficient balance');

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

// SPDX-License-Identifier: MIT
pragma solidity 0.6.12;

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

  function _msgData() internal view virtual returns (bytes memory) {
    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
    return msg.data;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {ILendingPoolAddressesProvider} from '../../interfaces/ILendingPoolAddressesProvider.sol';
import {ILendingPool} from '../../interfaces/ILendingPool.sol';

/**
 * @title IFlashLoanReceiver interface
 * @notice Interface for the Aave fee IFlashLoanReceiver.
 * @author Aave
 * @dev implement this interface to develop a flashloan-compatible flashLoanReceiver contract
 **/
interface IFlashLoanReceiver {
  function executeOperation(
    address[] calldata assets,
    uint256[] calldata amounts,
    uint256[] calldata premiums,
    address initiator,
    bytes calldata params
  ) external returns (bool);

  function ADDRESSES_PROVIDER() external view returns (ILendingPoolAddressesProvider);

  function LENDING_POOL() external view returns (ILendingPool);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {ILendingPoolAddressesProvider} from './ILendingPoolAddressesProvider.sol';
import {DataTypes} from '../protocol/libraries/types/DataTypes.sol';

interface ILendingPool {
  /**
   * @dev Emitted on deposit()
   * @param reserve The address of the underlying asset of the reserve
   * @param user The address initiating the deposit
   * @param onBehalfOf The beneficiary of the deposit, receiving the aTokens
   * @param amount The amount deposited
   * @param referral The referral code used
   **/
  event Deposit(
    address indexed reserve,
    address user,
    address indexed onBehalfOf,
    uint256 amount,
    uint16 indexed referral
  );

  /**
   * @dev Emitted on withdraw()
   * @param reserve The address of the underlyng asset being withdrawn
   * @param user The address initiating the withdrawal, owner of aTokens
   * @param to Address that will receive the underlying
   * @param amount The amount to be withdrawn
   **/
  event Withdraw(address indexed reserve, address indexed user, address indexed to, uint256 amount);

  /**
   * @dev Emitted on borrow() and flashLoan() when debt needs to be opened
   * @param reserve The address of the underlying asset being borrowed
   * @param user The address of the user initiating the borrow(), receiving the funds on borrow() or just
   * initiator of the transaction on flashLoan()
   * @param onBehalfOf The address that will be getting the debt
   * @param amount The amount borrowed out
   * @param borrowRateMode The rate mode: 1 for Stable, 2 for Variable
   * @param borrowRate The numeric rate at which the user has borrowed
   * @param referral The referral code used
   **/
  event Borrow(
    address indexed reserve,
    address user,
    address indexed onBehalfOf,
    uint256 amount,
    uint256 borrowRateMode,
    uint256 borrowRate,
    uint16 indexed referral
  );

  /**
   * @dev Emitted on repay()
   * @param reserve The address of the underlying asset of the reserve
   * @param user The beneficiary of the repayment, getting his debt reduced
   * @param repayer The address of the user initiating the repay(), providing the funds
   * @param amount The amount repaid
   **/
  event Repay(
    address indexed reserve,
    address indexed user,
    address indexed repayer,
    uint256 amount
  );

  /**
   * @dev Emitted on swapBorrowRateMode()
   * @param reserve The address of the underlying asset of the reserve
   * @param user The address of the user swapping his rate mode
   * @param rateMode The rate mode that the user wants to swap to
   **/
  event Swap(address indexed reserve, address indexed user, uint256 rateMode);

  /**
   * @dev Emitted on setUserUseReserveAsCollateral()
   * @param reserve The address of the underlying asset of the reserve
   * @param user The address of the user enabling the usage as collateral
   **/
  event ReserveUsedAsCollateralEnabled(address indexed reserve, address indexed user);

  /**
   * @dev Emitted on setUserUseReserveAsCollateral()
   * @param reserve The address of the underlying asset of the reserve
   * @param user The address of the user enabling the usage as collateral
   **/
  event ReserveUsedAsCollateralDisabled(address indexed reserve, address indexed user);

  /**
   * @dev Emitted on rebalanceStableBorrowRate()
   * @param reserve The address of the underlying asset of the reserve
   * @param user The address of the user for which the rebalance has been executed
   **/
  event RebalanceStableBorrowRate(address indexed reserve, address indexed user);

  /**
   * @dev Emitted on flashLoan()
   * @param target The address of the flash loan receiver contract
   * @param initiator The address initiating the flash loan
   * @param asset The address of the asset being flash borrowed
   * @param amount The amount flash borrowed
   * @param premium The fee flash borrowed
   * @param referralCode The referral code used
   **/
  event FlashLoan(
    address indexed target,
    address indexed initiator,
    address indexed asset,
    uint256 amount,
    uint256 premium,
    uint16 referralCode
  );

  /**
   * @dev Emitted when the pause is triggered.
   */
  event Paused();

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

  /**
   * @dev Emitted when a borrower is liquidated. This event is emitted by the LendingPool via
   * LendingPoolCollateral manager using a DELEGATECALL
   * This allows to have the events in the generated ABI for LendingPool.
   * @param collateralAsset The address of the underlying asset used as collateral, to receive as result of the liquidation
   * @param debtAsset The address of the underlying borrowed asset to be repaid with the liquidation
   * @param user The address of the borrower getting liquidated
   * @param debtToCover The debt amount of borrowed `asset` the liquidator wants to cover
   * @param liquidatedCollateralAmount The amount of collateral received by the liiquidator
   * @param liquidator The address of the liquidator
   * @param receiveAToken `true` if the liquidators wants to receive the collateral aTokens, `false` if he wants
   * to receive the underlying collateral asset directly
   **/
  event LiquidationCall(
    address indexed collateralAsset,
    address indexed debtAsset,
    address indexed user,
    uint256 debtToCover,
    uint256 liquidatedCollateralAmount,
    address liquidator,
    bool receiveAToken
  );

  /**
   * @dev Emitted when the state of a reserve is updated. NOTE: This event is actually declared
   * in the ReserveLogic library and emitted in the updateInterestRates() function. Since the function is internal,
   * the event will actually be fired by the LendingPool contract. The event is therefore replicated here so it
   * gets added to the LendingPool ABI
   * @param reserve The address of the underlying asset of the reserve
   * @param liquidityRate The new liquidity rate
   * @param stableBorrowRate The new stable borrow rate
   * @param variableBorrowRate The new variable borrow rate
   * @param liquidityIndex The new liquidity index
   * @param variableBorrowIndex The new variable borrow index
   **/
  event ReserveDataUpdated(
    address indexed reserve,
    uint256 liquidityRate,
    uint256 stableBorrowRate,
    uint256 variableBorrowRate,
    uint256 liquidityIndex,
    uint256 variableBorrowIndex
  );

  /**
   * @dev Deposits an `amount` of underlying asset into the reserve, receiving in return overlying aTokens.
   * - E.g. User deposits 100 USDC and gets in return 100 aUSDC
   * @param asset The address of the underlying asset to deposit
   * @param amount The amount to be deposited
   * @param onBehalfOf The address that will receive the aTokens, same as msg.sender if the user
   *   wants to receive them on his own wallet, or a different address if the beneficiary of aTokens
   *   is a different wallet
   * @param referralCode Code used to register the integrator originating the operation, for potential rewards.
   *   0 if the action is executed directly by the user, without any middle-man
   **/
  function deposit(
    address asset,
    uint256 amount,
    address onBehalfOf,
    uint16 referralCode
  ) external;

  /**
   * @dev Withdraws an `amount` of underlying asset from the reserve, burning the equivalent aTokens owned
   * E.g. User has 100 aUSDC, calls withdraw() and receives 100 USDC, burning the 100 aUSDC
   * @param asset The address of the underlying asset to withdraw
   * @param amount The underlying amount to be withdrawn
   *   - Send the value type(uint256).max in order to withdraw the whole aToken balance
   * @param to Address that will receive the underlying, same as msg.sender if the user
   *   wants to receive it on his own wallet, or a different address if the beneficiary is a
   *   different wallet
   * @return The final amount withdrawn
   **/
  function withdraw(
    address asset,
    uint256 amount,
    address to
  ) external returns (uint256);

  /**
   * @dev Allows users to borrow a specific `amount` of the reserve underlying asset, provided that the borrower
   * already deposited enough collateral, or he was given enough allowance by a credit delegator on the
   * corresponding debt token (StableDebtToken or VariableDebtToken)
   * - E.g. User borrows 100 USDC passing as `onBehalfOf` his own address, receiving the 100 USDC in his wallet
   *   and 100 stable/variable debt tokens, depending on the `interestRateMode`
   * @param asset The address of the underlying asset to borrow
   * @param amount The amount to be borrowed
   * @param interestRateMode The interest rate mode at which the user wants to borrow: 1 for Stable, 2 for Variable
   * @param referralCode Code used to register the integrator originating the operation, for potential rewards.
   *   0 if the action is executed directly by the user, without any middle-man
   * @param onBehalfOf Address of the user who will receive the debt. Should be the address of the borrower itself
   * calling the function if he wants to borrow against his own collateral, or the address of the credit delegator
   * if he has been given credit delegation allowance
   **/
  function borrow(
    address asset,
    uint256 amount,
    uint256 interestRateMode,
    uint16 referralCode,
    address onBehalfOf
  ) external;

  /**
   * @notice Repays a borrowed `amount` on a specific reserve, burning the equivalent debt tokens owned
   * - E.g. User repays 100 USDC, burning 100 variable/stable debt tokens of the `onBehalfOf` address
   * @param asset The address of the borrowed underlying asset previously borrowed
   * @param amount The amount to repay
   * - Send the value type(uint256).max in order to repay the whole debt for `asset` on the specific `debtMode`
   * @param rateMode The interest rate mode at of the debt the user wants to repay: 1 for Stable, 2 for Variable
   * @param onBehalfOf Address of the user who will get his debt reduced/removed. Should be the address of the
   * user calling the function if he wants to reduce/remove his own debt, or the address of any other
   * other borrower whose debt should be removed
   * @return The final amount repaid
   **/
  function repay(
    address asset,
    uint256 amount,
    uint256 rateMode,
    address onBehalfOf
  ) external returns (uint256);

  /**
   * @dev Allows a borrower to swap his debt between stable and variable mode, or viceversa
   * @param asset The address of the underlying asset borrowed
   * @param rateMode The rate mode that the user wants to swap to
   **/
  function swapBorrowRateMode(address asset, uint256 rateMode) external;

  /**
   * @dev Rebalances the stable interest rate of a user to the current stable rate defined on the reserve.
   * - Users can be rebalanced if the following conditions are satisfied:
   *     1. Usage ratio is above 95%
   *     2. the current deposit APY is below REBALANCE_UP_THRESHOLD * maxVariableBorrowRate, which means that too much has been
   *        borrowed at a stable rate and depositors are not earning enough
   * @param asset The address of the underlying asset borrowed
   * @param user The address of the user to be rebalanced
   **/
  function rebalanceStableBorrowRate(address asset, address user) external;

  /**
   * @dev Allows depositors to enable/disable a specific deposited asset as collateral
   * @param asset The address of the underlying asset deposited
   * @param useAsCollateral `true` if the user wants to use the deposit as collateral, `false` otherwise
   **/
  function setUserUseReserveAsCollateral(address asset, bool useAsCollateral) external;

  /**
   * @dev Function to liquidate a non-healthy position collateral-wise, with Health Factor below 1
   * - The caller (liquidator) covers `debtToCover` amount of debt of the user getting liquidated, and receives
   *   a proportionally amount of the `collateralAsset` plus a bonus to cover market risk
   * @param collateralAsset The address of the underlying asset used as collateral, to receive as result of the liquidation
   * @param debtAsset The address of the underlying borrowed asset to be repaid with the liquidation
   * @param user The address of the borrower getting liquidated
   * @param debtToCover The debt amount of borrowed `asset` the liquidator wants to cover
   * @param receiveAToken `true` if the liquidators wants to receive the collateral aTokens, `false` if he wants
   * to receive the underlying collateral asset directly
   **/
  function liquidationCall(
    address collateralAsset,
    address debtAsset,
    address user,
    uint256 debtToCover,
    bool receiveAToken
  ) external;

  /**
   * @dev Allows smartcontracts to access the liquidity of the pool within one transaction,
   * as long as the amount taken plus a fee is returned.
   * IMPORTANT There are security concerns for developers of flashloan receiver contracts that must be kept into consideration.
   * For further details please visit https://developers.aave.com
   * @param receiverAddress The address of the contract receiving the funds, implementing the IFlashLoanReceiver interface
   * @param assets The addresses of the assets being flash-borrowed
   * @param amounts The amounts amounts being flash-borrowed
   * @param modes Types of the debt to open if the flash loan is not returned:
   *   0 -> Don't open any debt, just revert if funds can't be transferred from the receiver
   *   1 -> Open debt at stable rate for the value of the amount flash-borrowed to the `onBehalfOf` address
   *   2 -> Open debt at variable rate for the value of the amount flash-borrowed to the `onBehalfOf` address
   * @param onBehalfOf The address  that will receive the debt in the case of using on `modes` 1 or 2
   * @param params Variadic packed params to pass to the receiver as extra information
   * @param referralCode Code used to register the integrator originating the operation, for potential rewards.
   *   0 if the action is executed directly by the user, without any middle-man
   **/
  function flashLoan(
    address receiverAddress,
    address[] calldata assets,
    uint256[] calldata amounts,
    uint256[] calldata modes,
    address onBehalfOf,
    bytes calldata params,
    uint16 referralCode
  ) external;

  /**
   * @dev Returns the user account data across all the reserves
   * @param user The address of the user
   * @return totalCollateralETH the total collateral in ETH of the user
   * @return totalDebtETH the total debt in ETH of the user
   * @return availableBorrowsETH the borrowing power left of the user
   * @return currentLiquidationThreshold the liquidation threshold of the user
   * @return ltv the loan to value of the user
   * @return healthFactor the current health factor of the user
   **/
  function getUserAccountData(address user)
    external
    view
    returns (
      uint256 totalCollateralETH,
      uint256 totalDebtETH,
      uint256 availableBorrowsETH,
      uint256 currentLiquidationThreshold,
      uint256 ltv,
      uint256 healthFactor
    );

  function initReserve(
    address reserve,
    address aTokenAddress,
    address stableDebtAddress,
    address variableDebtAddress,
    address interestRateStrategyAddress
  ) external;

  function setReserveInterestRateStrategyAddress(address reserve, address rateStrategyAddress)
    external;

  function setConfiguration(address reserve, uint256 configuration) external;

  /**
   * @dev Returns the configuration of the reserve
   * @param asset The address of the underlying asset of the reserve
   * @return The configuration of the reserve
   **/
  function getConfiguration(address asset)
    external
    view
    returns (DataTypes.ReserveConfigurationMap memory);

  /**
   * @dev Returns the configuration of the user across all the reserves
   * @param user The user address
   * @return The configuration of the user
   **/
  function getUserConfiguration(address user)
    external
    view
    returns (DataTypes.UserConfigurationMap memory);

  /**
   * @dev Returns the normalized income normalized income of the reserve
   * @param asset The address of the underlying asset of the reserve
   * @return The reserve's normalized income
   */
  function getReserveNormalizedIncome(address asset) external view returns (uint256);

  /**
   * @dev Returns the normalized variable debt per unit of asset
   * @param asset The address of the underlying asset of the reserve
   * @return The reserve normalized variable debt
   */
  function getReserveNormalizedVariableDebt(address asset) external view returns (uint256);

  /**
   * @dev Returns the state and configuration of the reserve
   * @param asset The address of the underlying asset of the reserve
   * @return The state of the reserve
   **/
  function getReserveData(address asset) external view returns (DataTypes.ReserveData memory);

  function finalizeTransfer(
    address asset,
    address from,
    address to,
    uint256 amount,
    uint256 balanceFromAfter,
    uint256 balanceToBefore
  ) external;

  function getReservesList() external view returns (address[] memory);

  function getAddressesProvider() external view returns (ILendingPoolAddressesProvider);

  function setPause(bool val) external;

  function paused() external view returns (bool);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {BaseUniswapAdapter} from './BaseUniswapAdapter.sol';
import {ILendingPoolAddressesProvider} from '../interfaces/ILendingPoolAddressesProvider.sol';
import {IUniswapV2Router02} from '../interfaces/IUniswapV2Router02.sol';
import {IERC20} from '../dependencies/openzeppelin/contracts/IERC20.sol';
import {DataTypes} from '../protocol/libraries/types/DataTypes.sol';

/**
 * @title UniswapRepayAdapter
 * @notice Uniswap V2 Adapter to perform a repay of a debt with collateral.
 * @author Aave
 **/
contract UniswapRepayAdapter is BaseUniswapAdapter {
  struct RepayParams {
    address collateralAsset;
    uint256 collateralAmount;
    uint256 rateMode;
    PermitSignature permitSignature;
    bool useEthPath;
  }

  constructor(
    ILendingPoolAddressesProvider addressesProvider,
    IUniswapV2Router02 uniswapRouter,
    address wethAddress
  ) public BaseUniswapAdapter(addressesProvider, uniswapRouter, wethAddress) {}

  /**
   * @dev Uses the received funds from the flash loan to repay a debt on the protocol on behalf of the user. Then pulls
   * the collateral from the user and swaps it to the debt asset to repay the flash loan.
   * The user should give this contract allowance to pull the ATokens in order to withdraw the underlying asset, swap it
   * and repay the flash loan.
   * Supports only one asset on the flash loan.
   * @param assets Address of debt asset
   * @param amounts Amount of the debt to be repaid
   * @param premiums Fee of the flash loan
   * @param initiator Address of the user
   * @param params Additional variadic field to include extra params. Expected parameters:
   *   address collateralAsset Address of the reserve to be swapped
   *   uint256 collateralAmount Amount of reserve to be swapped
   *   uint256 rateMode Rate modes of the debt to be repaid
   *   uint256 permitAmount Amount for the permit signature
   *   uint256 deadline Deadline for the permit signature
   *   uint8 v V param for the permit signature
   *   bytes32 r R param for the permit signature
   *   bytes32 s S param for the permit signature
   */
  function executeOperation(
    address[] calldata assets,
    uint256[] calldata amounts,
    uint256[] calldata premiums,
    address initiator,
    bytes calldata params
  ) external override returns (bool) {
    require(msg.sender == address(LENDING_POOL), 'CALLER_MUST_BE_LENDING_POOL');

    RepayParams memory decodedParams = _decodeParams(params);

    _swapAndRepay(
      decodedParams.collateralAsset,
      assets[0],
      amounts[0],
      decodedParams.collateralAmount,
      decodedParams.rateMode,
      initiator,
      premiums[0],
      decodedParams.permitSignature,
      decodedParams.useEthPath
    );

    return true;
  }

  /**
   * @dev Swaps the user collateral for the debt asset and then repay the debt on the protocol on behalf of the user
   * without using flash loans. This method can be used when the temporary transfer of the collateral asset to this
   * contract does not affect the user position.
   * The user should give this contract allowance to pull the ATokens in order to withdraw the underlying asset
   * @param collateralAsset Address of asset to be swapped
   * @param debtAsset Address of debt asset
   * @param collateralAmount Amount of the collateral to be swapped
   * @param debtRepayAmount Amount of the debt to be repaid
   * @param debtRateMode Rate mode of the debt to be repaid
   * @param permitSignature struct containing the permit signature
   * @param useEthPath struct containing the permit signature

   */
  function swapAndRepay(
    address collateralAsset,
    address debtAsset,
    uint256 collateralAmount,
    uint256 debtRepayAmount,
    uint256 debtRateMode,
    PermitSignature calldata permitSignature,
    bool useEthPath
  ) external {
    DataTypes.ReserveData memory collateralReserveData = _getReserveData(collateralAsset);
    DataTypes.ReserveData memory debtReserveData = _getReserveData(debtAsset);

    address debtToken =
      DataTypes.InterestRateMode(debtRateMode) == DataTypes.InterestRateMode.STABLE
        ? debtReserveData.stableDebtTokenAddress
        : debtReserveData.variableDebtTokenAddress;

    uint256 currentDebt = IERC20(debtToken).balanceOf(msg.sender);
    uint256 amountToRepay = debtRepayAmount <= currentDebt ? debtRepayAmount : currentDebt;

    if (collateralAsset != debtAsset) {
      uint256 maxCollateralToSwap = collateralAmount;
      if (amountToRepay < debtRepayAmount) {
        maxCollateralToSwap = maxCollateralToSwap.mul(amountToRepay).div(debtRepayAmount);
      }

      // Get exact collateral needed for the swap to avoid leftovers
      uint256[] memory amounts =
        _getAmountsIn(collateralAsset, debtAsset, amountToRepay, useEthPath);
      require(amounts[0] <= maxCollateralToSwap, 'slippage too high');

      // Pull aTokens from user
      _pullAToken(
        collateralAsset,
        collateralReserveData.aTokenAddress,
        msg.sender,
        amounts[0],
        permitSignature
      );

      // Swap collateral for debt asset
      _swapTokensForExactTokens(collateralAsset, debtAsset, amounts[0], amountToRepay, useEthPath);
    } else {
      // Pull aTokens from user
      _pullAToken(
        collateralAsset,
        collateralReserveData.aTokenAddress,
        msg.sender,
        amountToRepay,
        permitSignature
      );
    }

    // Repay debt. Approves 0 first to comply with tokens that implement the anti frontrunning approval fix
    IERC20(debtAsset).safeApprove(address(LENDING_POOL), 0);
    IERC20(debtAsset).safeApprove(address(LENDING_POOL), amountToRepay);
    LENDING_POOL.repay(debtAsset, amountToRepay, debtRateMode, msg.sender);
  }

  /**
   * @dev Perform the repay of the debt, pulls the initiator collateral and swaps to repay the flash loan
   *
   * @param collateralAsset Address of token to be swapped
   * @param debtAsset Address of debt token to be received from the swap
   * @param amount Amount of the debt to be repaid
   * @param collateralAmount Amount of the reserve to be swapped
   * @param rateMode Rate mode of the debt to be repaid
   * @param initiator Address of the user
   * @param premium Fee of the flash loan
   * @param permitSignature struct containing the permit signature
   */
  function _swapAndRepay(
    address collateralAsset,
    address debtAsset,
    uint256 amount,
    uint256 collateralAmount,
    uint256 rateMode,
    address initiator,
    uint256 premium,
    PermitSignature memory permitSignature,
    bool useEthPath
  ) internal {
    DataTypes.ReserveData memory collateralReserveData = _getReserveData(collateralAsset);

    // Repay debt. Approves for 0 first to comply with tokens that implement the anti frontrunning approval fix.
    IERC20(debtAsset).safeApprove(address(LENDING_POOL), 0);
    IERC20(debtAsset).safeApprove(address(LENDING_POOL), amount);
    uint256 repaidAmount = IERC20(debtAsset).balanceOf(address(this));
    LENDING_POOL.repay(debtAsset, amount, rateMode, initiator);
    repaidAmount = repaidAmount.sub(IERC20(debtAsset).balanceOf(address(this)));

    if (collateralAsset != debtAsset) {
      uint256 maxCollateralToSwap = collateralAmount;
      if (repaidAmount < amount) {
        maxCollateralToSwap = maxCollateralToSwap.mul(repaidAmount).div(amount);
      }

      uint256 neededForFlashLoanDebt = repaidAmount.add(premium);
      uint256[] memory amounts =
        _getAmountsIn(collateralAsset, debtAsset, neededForFlashLoanDebt, useEthPath);
      require(amounts[0] <= maxCollateralToSwap, 'slippage too high');

      // Pull aTokens from user
      _pullAToken(
        collateralAsset,
        collateralReserveData.aTokenAddress,
        initiator,
        amounts[0],
        permitSignature
      );

      // Swap collateral asset to the debt asset
      _swapTokensForExactTokens(
        collateralAsset,
        debtAsset,
        amounts[0],
        neededForFlashLoanDebt,
        useEthPath
      );
    } else {
      // Pull aTokens from user
      _pullAToken(
        collateralAsset,
        collateralReserveData.aTokenAddress,
        initiator,
        repaidAmount.add(premium),
        permitSignature
      );
    }

    // Repay flashloan. Approves for 0 first to comply with tokens that implement the anti frontrunning approval fix.
    IERC20(debtAsset).safeApprove(address(LENDING_POOL), 0);
    IERC20(debtAsset).safeApprove(address(LENDING_POOL), amount.add(premium));
  }

  /**
   * @dev Decodes debt information encoded in the flash loan params
   * @param params Additional variadic field to include extra params. Expected parameters:
   *   address collateralAsset Address of the reserve to be swapped
   *   uint256 collateralAmount Amount of reserve to be swapped
   *   uint256 rateMode Rate modes of the debt to be repaid
   *   uint256 permitAmount Amount for the permit signature
   *   uint256 deadline Deadline for the permit signature
   *   uint8 v V param for the permit signature
   *   bytes32 r R param for the permit signature
   *   bytes32 s S param for the permit signature
   *   bool useEthPath use WETH path route
   * @return RepayParams struct containing decoded params
   */
  function _decodeParams(bytes memory params) internal pure returns (RepayParams memory) {
    (
      address collateralAsset,
      uint256 collateralAmount,
      uint256 rateMode,
      uint256 permitAmount,
      uint256 deadline,
      uint8 v,
      bytes32 r,
      bytes32 s,
      bool useEthPath
    ) =
      abi.decode(
        params,
        (address, uint256, uint256, uint256, uint256, uint8, bytes32, bytes32, bool)
      );

    return
      RepayParams(
        collateralAsset,
        collateralAmount,
        rateMode,
        PermitSignature(permitAmount, deadline, v, r, s),
        useEthPath
      );
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {SafeMath} from '../../dependencies/openzeppelin/contracts//SafeMath.sol';
import {IERC20} from '../../dependencies/openzeppelin/contracts//IERC20.sol';
import {IAToken} from '../../interfaces/IAToken.sol';
import {IStableDebtToken} from '../../interfaces/IStableDebtToken.sol';
import {IVariableDebtToken} from '../../interfaces/IVariableDebtToken.sol';
import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
import {ILendingPoolCollateralManager} from '../../interfaces/ILendingPoolCollateralManager.sol';
import {VersionedInitializable} from '../libraries/aave-upgradeability/VersionedInitializable.sol';
import {GenericLogic} from '../libraries/logic/GenericLogic.sol';
import {Helpers} from '../libraries/helpers/Helpers.sol';
import {WadRayMath} from '../libraries/math/WadRayMath.sol';
import {PercentageMath} from '../libraries/math/PercentageMath.sol';
import {SafeERC20} from '../../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {Errors} from '../libraries/helpers/Errors.sol';
import {ValidationLogic} from '../libraries/logic/ValidationLogic.sol';
import {DataTypes} from '../libraries/types/DataTypes.sol';
import {LendingPoolStorage} from './LendingPoolStorage.sol';

/**
 * @title LendingPoolCollateralManager contract
 * @author Aave
 * @dev Implements actions involving management of collateral in the protocol, the main one being the liquidations
 * IMPORTANT This contract will run always via DELEGATECALL, through the LendingPool, so the chain of inheritance
 * is the same as the LendingPool, to have compatible storage layouts
 **/
contract LendingPoolCollateralManager is
  ILendingPoolCollateralManager,
  VersionedInitializable,
  LendingPoolStorage
{
  using SafeERC20 for IERC20;
  using SafeMath for uint256;
  using WadRayMath for uint256;
  using PercentageMath for uint256;

  uint256 internal constant LIQUIDATION_CLOSE_FACTOR_PERCENT = 5000;

  struct LiquidationCallLocalVars {
    uint256 userCollateralBalance;
    uint256 userStableDebt;
    uint256 userVariableDebt;
    uint256 maxLiquidatableDebt;
    uint256 actualDebtToLiquidate;
    uint256 liquidationRatio;
    uint256 maxAmountCollateralToLiquidate;
    uint256 userStableRate;
    uint256 maxCollateralToLiquidate;
    uint256 debtAmountNeeded;
    uint256 healthFactor;
    uint256 liquidatorPreviousATokenBalance;
    IAToken collateralAtoken;
    bool isCollateralEnabled;
    DataTypes.InterestRateMode borrowRateMode;
    uint256 errorCode;
    string errorMsg;
  }

  /**
   * @dev As thIS contract extends the VersionedInitializable contract to match the state
   * of the LendingPool contract, the getRevision() function is needed, but the value is not
   * important, as the initialize() function will never be called here
   */
  function getRevision() internal pure override returns (uint256) {
    return 0;
  }

  /**
   * @dev Function to liquidate a position if its Health Factor drops below 1
   * - The caller (liquidator) covers `debtToCover` amount of debt of the user getting liquidated, and receives
   *   a proportionally amount of the `collateralAsset` plus a bonus to cover market risk
   * @param collateralAsset The address of the underlying asset used as collateral, to receive as result of the liquidation
   * @param debtAsset The address of the underlying borrowed asset to be repaid with the liquidation
   * @param user The address of the borrower getting liquidated
   * @param debtToCover The debt amount of borrowed `asset` the liquidator wants to cover
   * @param receiveAToken `true` if the liquidators wants to receive the collateral aTokens, `false` if he wants
   * to receive the underlying collateral asset directly
   **/
  function liquidationCall(
    address collateralAsset,
    address debtAsset,
    address user,
    uint256 debtToCover,
    bool receiveAToken
  ) external override returns (uint256, string memory) {
    DataTypes.ReserveData storage collateralReserve = _reserves[collateralAsset];
    DataTypes.ReserveData storage debtReserve = _reserves[debtAsset];
    DataTypes.UserConfigurationMap storage userConfig = _usersConfig[user];

    LiquidationCallLocalVars memory vars;

    (, , , , vars.healthFactor) = GenericLogic.calculateUserAccountData(
      user,
      _reserves,
      userConfig,
      _reservesList,
      _reservesCount,
      _addressesProvider.getPriceOracle()
    );

    (vars.userStableDebt, vars.userVariableDebt) = Helpers.getUserCurrentDebt(user, debtReserve);

    (vars.errorCode, vars.errorMsg) = ValidationLogic.validateLiquidationCall(
      collateralReserve,
      debtReserve,
      userConfig,
      vars.healthFactor,
      vars.userStableDebt,
      vars.userVariableDebt
    );

    if (Errors.CollateralManagerErrors(vars.errorCode) != Errors.CollateralManagerErrors.NO_ERROR) {
      return (vars.errorCode, vars.errorMsg);
    }

    vars.collateralAtoken = IAToken(collateralReserve.aTokenAddress);

    vars.userCollateralBalance = vars.collateralAtoken.balanceOf(user);

    vars.maxLiquidatableDebt = vars.userStableDebt.add(vars.userVariableDebt).percentMul(
      LIQUIDATION_CLOSE_FACTOR_PERCENT
    );

    vars.actualDebtToLiquidate = debtToCover > vars.maxLiquidatableDebt
      ? vars.maxLiquidatableDebt
      : debtToCover;

    (
      vars.maxCollateralToLiquidate,
      vars.debtAmountNeeded
    ) = _calculateAvailableCollateralToLiquidate(
      collateralReserve,
      debtReserve,
      collateralAsset,
      debtAsset,
      vars.actualDebtToLiquidate,
      vars.userCollateralBalance
    );

    // If debtAmountNeeded < actualDebtToLiquidate, there isn't enough
    // collateral to cover the actual amount that is being liquidated, hence we liquidate
    // a smaller amount

    if (vars.debtAmountNeeded < vars.actualDebtToLiquidate) {
      vars.actualDebtToLiquidate = vars.debtAmountNeeded;
    }

    // If the liquidator reclaims the underlying asset, we make sure there is enough available liquidity in the
    // collateral reserve
    if (!receiveAToken) {
      uint256 currentAvailableCollateral =
        IERC20(collateralAsset).balanceOf(address(vars.collateralAtoken));
      if (currentAvailableCollateral < vars.maxCollateralToLiquidate) {
        return (
          uint256(Errors.CollateralManagerErrors.NOT_ENOUGH_LIQUIDITY),
          Errors.LPCM_NOT_ENOUGH_LIQUIDITY_TO_LIQUIDATE
        );
      }
    }

    debtReserve.updateState();

    if (vars.userVariableDebt >= vars.actualDebtToLiquidate) {
      IVariableDebtToken(debtReserve.variableDebtTokenAddress).burn(
        user,
        vars.actualDebtToLiquidate,
        debtReserve.variableBorrowIndex
      );
    } else {
      // If the user doesn't have variable debt, no need to try to burn variable debt tokens
      if (vars.userVariableDebt > 0) {
        IVariableDebtToken(debtReserve.variableDebtTokenAddress).burn(
          user,
          vars.userVariableDebt,
          debtReserve.variableBorrowIndex
        );
      }
      IStableDebtToken(debtReserve.stableDebtTokenAddress).burn(
        user,
        vars.actualDebtToLiquidate.sub(vars.userVariableDebt)
      );
    }

    debtReserve.updateInterestRates(
      debtAsset,
      debtReserve.aTokenAddress,
      vars.actualDebtToLiquidate,
      0
    );

    if (receiveAToken) {
      vars.liquidatorPreviousATokenBalance = IERC20(vars.collateralAtoken).balanceOf(msg.sender);
      vars.collateralAtoken.transferOnLiquidation(user, msg.sender, vars.maxCollateralToLiquidate);

      if (vars.liquidatorPreviousATokenBalance == 0) {
        DataTypes.UserConfigurationMap storage liquidatorConfig = _usersConfig[msg.sender];
        liquidatorConfig.setUsingAsCollateral(collateralReserve.id, true);
        emit ReserveUsedAsCollateralEnabled(collateralAsset, msg.sender);
      }
    } else {
      collateralReserve.updateState();
      collateralReserve.updateInterestRates(
        collateralAsset,
        address(vars.collateralAtoken),
        0,
        vars.maxCollateralToLiquidate
      );

      // Burn the equivalent amount of aToken, sending the underlying to the liquidator
      vars.collateralAtoken.burn(
        user,
        msg.sender,
        vars.maxCollateralToLiquidate,
        collateralReserve.liquidityIndex
      );
    }

    // If the collateral being liquidated is equal to the user balance,
    // we set the currency as not being used as collateral anymore
    if (vars.maxCollateralToLiquidate == vars.userCollateralBalance) {
      userConfig.setUsingAsCollateral(collateralReserve.id, false);
      emit ReserveUsedAsCollateralDisabled(collateralAsset, user);
    }

    // Transfers the debt asset being repaid to the aToken, where the liquidity is kept
    IERC20(debtAsset).safeTransferFrom(
      msg.sender,
      debtReserve.aTokenAddress,
      vars.actualDebtToLiquidate
    );

    emit LiquidationCall(
      collateralAsset,
      debtAsset,
      user,
      vars.actualDebtToLiquidate,
      vars.maxCollateralToLiquidate,
      msg.sender,
      receiveAToken
    );

    return (uint256(Errors.CollateralManagerErrors.NO_ERROR), Errors.LPCM_NO_ERRORS);
  }

  struct AvailableCollateralToLiquidateLocalVars {
    uint256 userCompoundedBorrowBalance;
    uint256 liquidationBonus;
    uint256 collateralPrice;
    uint256 debtAssetPrice;
    uint256 maxAmountCollateralToLiquidate;
    uint256 debtAssetDecimals;
    uint256 collateralDecimals;
  }

  /**
   * @dev Calculates how much of a specific collateral can be liquidated, given
   * a certain amount of debt asset.
   * - This function needs to be called after all the checks to validate the liquidation have been performed,
   *   otherwise it might fail.
   * @param collateralReserve The data of the collateral reserve
   * @param debtReserve The data of the debt reserve
   * @param collateralAsset The address of the underlying asset used as collateral, to receive as result of the liquidation
   * @param debtAsset The address of the underlying borrowed asset to be repaid with the liquidation
   * @param debtToCover The debt amount of borrowed `asset` the liquidator wants to cover
   * @param userCollateralBalance The collateral balance for the specific `collateralAsset` of the user being liquidated
   * @return collateralAmount: The maximum amount that is possible to liquidate given all the liquidation constraints
   *                           (user balance, close factor)
   *         debtAmountNeeded: The amount to repay with the liquidation
   **/
  function _calculateAvailableCollateralToLiquidate(
    DataTypes.ReserveData storage collateralReserve,
    DataTypes.ReserveData storage debtReserve,
    address collateralAsset,
    address debtAsset,
    uint256 debtToCover,
    uint256 userCollateralBalance
  ) internal view returns (uint256, uint256) {
    uint256 collateralAmount = 0;
    uint256 debtAmountNeeded = 0;
    IPriceOracleGetter oracle = IPriceOracleGetter(_addressesProvider.getPriceOracle());

    AvailableCollateralToLiquidateLocalVars memory vars;

    vars.collateralPrice = oracle.getAssetPrice(collateralAsset);
    vars.debtAssetPrice = oracle.getAssetPrice(debtAsset);

    (, , vars.liquidationBonus, vars.collateralDecimals, ) = collateralReserve
      .configuration
      .getParams();
    vars.debtAssetDecimals = debtReserve.configuration.getDecimals();

    // This is the maximum possible amount of the selected collateral that can be liquidated, given the
    // max amount of liquidatable debt
    vars.maxAmountCollateralToLiquidate = vars
      .debtAssetPrice
      .mul(debtToCover)
      .mul(10**vars.collateralDecimals)
      .percentMul(vars.liquidationBonus)
      .div(vars.collateralPrice.mul(10**vars.debtAssetDecimals));

    if (vars.maxAmountCollateralToLiquidate > userCollateralBalance) {
      collateralAmount = userCollateralBalance;
      debtAmountNeeded = vars
        .collateralPrice
        .mul(collateralAmount)
        .mul(10**vars.debtAssetDecimals)
        .div(vars.debtAssetPrice.mul(10**vars.collateralDecimals))
        .percentDiv(vars.liquidationBonus);
    } else {
      collateralAmount = vars.maxAmountCollateralToLiquidate;
      debtAmountNeeded = debtToCover;
    }
    return (collateralAmount, debtAmountNeeded);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IERC20} from '../dependencies/openzeppelin/contracts/IERC20.sol';
import {IScaledBalanceToken} from './IScaledBalanceToken.sol';
import {IInitializableAToken} from './IInitializableAToken.sol';
import {IAaveIncentivesController} from './IAaveIncentivesController.sol';

interface IAToken is IERC20, IScaledBalanceToken, IInitializableAToken {
  /**
   * @dev Emitted after the mint action
   * @param from The address performing the mint
   * @param value The amount being
   * @param index The new liquidity index of the reserve
   **/
  event Mint(address indexed from, uint256 value, uint256 index);

  /**
   * @dev Mints `amount` aTokens to `user`
   * @param user The address receiving the minted tokens
   * @param amount The amount of tokens getting minted
   * @param index The new liquidity index of the reserve
   * @return `true` if the the previous balance of the user was 0
   */
  function mint(
    address user,
    uint256 amount,
    uint256 index
  ) external returns (bool);

  /**
   * @dev Emitted after aTokens are burned
   * @param from The owner of the aTokens, getting them burned
   * @param target The address that will receive the underlying
   * @param value The amount being burned
   * @param index The new liquidity index of the reserve
   **/
  event Burn(address indexed from, address indexed target, uint256 value, uint256 index);

  /**
   * @dev Emitted during the transfer action
   * @param from The user whose tokens are being transferred
   * @param to The recipient
   * @param value The amount being transferred
   * @param index The new liquidity index of the reserve
   **/
  event BalanceTransfer(address indexed from, address indexed to, uint256 value, uint256 index);

  /**
   * @dev Burns aTokens from `user` and sends the equivalent amount of underlying to `receiverOfUnderlying`
   * @param user The owner of the aTokens, getting them burned
   * @param receiverOfUnderlying The address that will receive the underlying
   * @param amount The amount being burned
   * @param index The new liquidity index of the reserve
   **/
  function burn(
    address user,
    address receiverOfUnderlying,
    uint256 amount,
    uint256 index
  ) external;

  /**
   * @dev Mints aTokens to the reserve treasury
   * @param amount The amount of tokens getting minted
   * @param index The new liquidity index of the reserve
   */
  function mintToTreasury(uint256 amount, uint256 index) external;

  /**
   * @dev Transfers aTokens in the event of a borrow being liquidated, in case the liquidators reclaims the aToken
   * @param from The address getting liquidated, current owner of the aTokens
   * @param to The recipient
   * @param value The amount of tokens getting transferred
   **/
  function transferOnLiquidation(
    address from,
    address to,
    uint256 value
  ) external;

  /**
   * @dev Transfers the underlying asset to `target`. Used by the LendingPool to transfer
   * assets in borrow(), withdraw() and flashLoan()
   * @param user The recipient of the underlying
   * @param amount The amount getting transferred
   * @return The amount transferred
   **/
  function transferUnderlyingTo(address user, uint256 amount) external returns (uint256);

  /**
   * @dev Invoked to execute actions on the aToken side after a repayment.
   * @param user The user executing the repayment
   * @param amount The amount getting repaid
   **/
  function handleRepayment(address user, uint256 amount) external;

  /**
   * @dev Returns the address of the incentives controller contract
   **/
  function getIncentivesController() external view returns (IAaveIncentivesController);

  /**
   * @dev Returns the address of the underlying asset of this aToken (E.g. WETH for aWETH)
   **/
  function UNDERLYING_ASSET_ADDRESS() external view returns (address);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IInitializableDebtToken} from './IInitializableDebtToken.sol';
import {IAaveIncentivesController} from './IAaveIncentivesController.sol';

/**
 * @title IStableDebtToken
 * @notice Defines the interface for the stable debt token
 * @dev It does not inherit from IERC20 to save in code size
 * @author Aave
 **/

interface IStableDebtToken is IInitializableDebtToken {
  /**
   * @dev Emitted when new stable debt is minted
   * @param user The address of the user who triggered the minting
   * @param onBehalfOf The recipient of stable debt tokens
   * @param amount The amount minted
   * @param currentBalance The current balance of the user
   * @param balanceIncrease The increase in balance since the last action of the user
   * @param newRate The rate of the debt after the minting
   * @param avgStableRate The new average stable rate after the minting
   * @param newTotalSupply The new total supply of the stable debt token after the action
   **/
  event Mint(
    address indexed user,
    address indexed onBehalfOf,
    uint256 amount,
    uint256 currentBalance,
    uint256 balanceIncrease,
    uint256 newRate,
    uint256 avgStableRate,
    uint256 newTotalSupply
  );

  /**
   * @dev Emitted when new stable debt is burned
   * @param user The address of the user
   * @param amount The amount being burned
   * @param currentBalance The current balance of the user
   * @param balanceIncrease The the increase in balance since the last action of the user
   * @param avgStableRate The new average stable rate after the burning
   * @param newTotalSupply The new total supply of the stable debt token after the action
   **/
  event Burn(
    address indexed user,
    uint256 amount,
    uint256 currentBalance,
    uint256 balanceIncrease,
    uint256 avgStableRate,
    uint256 newTotalSupply
  );

  /**
   * @dev Mints debt token to the `onBehalfOf` address.
   * - The resulting rate is the weighted average between the rate of the new debt
   * and the rate of the previous debt
   * @param user The address receiving the borrowed underlying, being the delegatee in case
   * of credit delegate, or same as `onBehalfOf` otherwise
   * @param onBehalfOf The address receiving the debt tokens
   * @param amount The amount of debt tokens to mint
   * @param rate The rate of the debt being minted
   **/
  function mint(
    address user,
    address onBehalfOf,
    uint256 amount,
    uint256 rate
  ) external returns (bool);

  /**
   * @dev Burns debt of `user`
   * - The resulting rate is the weighted average between the rate of the new debt
   * and the rate of the previous debt
   * @param user The address of the user getting his debt burned
   * @param amount The amount of debt tokens getting burned
   **/
  function burn(address user, uint256 amount) external;

  /**
   * @dev Returns the average rate of all the stable rate loans.
   * @return The average stable rate
   **/
  function getAverageStableRate() external view returns (uint256);

  /**
   * @dev Returns the stable rate of the user debt
   * @return The stable rate of the user
   **/
  function getUserStableRate(address user) external view returns (uint256);

  /**
   * @dev Returns the timestamp of the last update of the user
   * @return The timestamp
   **/
  function getUserLastUpdated(address user) external view returns (uint40);

  /**
   * @dev Returns the principal, the total supply and the average stable rate
   **/
  function getSupplyData()
    external
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint40
    );

  /**
   * @dev Returns the timestamp of the last update of the total supply
   * @return The timestamp
   **/
  function getTotalSupplyLastUpdated() external view returns (uint40);

  /**
   * @dev Returns the total supply and the average stable rate
   **/
  function getTotalSupplyAndAvgRate() external view returns (uint256, uint256);

  /**
   * @dev Returns the principal debt balance of the user
   * @return The debt balance of the user since the last burn/mint action
   **/
  function principalBalanceOf(address user) external view returns (uint256);

  /**
   * @dev Returns the address of the incentives controller contract
   **/
  function getIncentivesController() external view returns (IAaveIncentivesController);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IScaledBalanceToken} from './IScaledBalanceToken.sol';
import {IInitializableDebtToken} from './IInitializableDebtToken.sol';
import {IAaveIncentivesController} from './IAaveIncentivesController.sol';

/**
 * @title IVariableDebtToken
 * @author Aave
 * @notice Defines the basic interface for a variable debt token.
 **/
interface IVariableDebtToken is IScaledBalanceToken, IInitializableDebtToken {
  /**
   * @dev Emitted after the mint action
   * @param from The address performing the mint
   * @param onBehalfOf The address of the user on which behalf minting has been performed
   * @param value The amount to be minted
   * @param index The last index of the reserve
   **/
  event Mint(address indexed from, address indexed onBehalfOf, uint256 value, uint256 index);

  /**
   * @dev Mints debt token to the `onBehalfOf` address
   * @param user The address receiving the borrowed underlying, being the delegatee in case
   * of credit delegate, or same as `onBehalfOf` otherwise
   * @param onBehalfOf The address receiving the debt tokens
   * @param amount The amount of debt being minted
   * @param index The variable debt index of the reserve
   * @return `true` if the the previous balance of the user is 0
   **/
  function mint(
    address user,
    address onBehalfOf,
    uint256 amount,
    uint256 index
  ) external returns (bool);

  /**
   * @dev Emitted when variable debt is burnt
   * @param user The user which debt has been burned
   * @param amount The amount of debt being burned
   * @param index The index of the user
   **/
  event Burn(address indexed user, uint256 amount, uint256 index);

  /**
   * @dev Burns user variable debt
   * @param user The user which debt is burnt
   * @param index The variable debt index of the reserve
   **/
  function burn(
    address user,
    uint256 amount,
    uint256 index
  ) external;

  /**
   * @dev Returns the address of the incentives controller contract
   **/
  function getIncentivesController() external view returns (IAaveIncentivesController);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title ILendingPoolCollateralManager
 * @author Aave
 * @notice Defines the actions involving management of collateral in the protocol.
 **/
interface ILendingPoolCollateralManager {
  /**
   * @dev Emitted when a borrower is liquidated
   * @param collateral The address of the collateral being liquidated
   * @param principal The address of the reserve
   * @param user The address of the user being liquidated
   * @param debtToCover The total amount liquidated
   * @param liquidatedCollateralAmount The amount of collateral being liquidated
   * @param liquidator The address of the liquidator
   * @param receiveAToken true if the liquidator wants to receive aTokens, false otherwise
   **/
  event LiquidationCall(
    address indexed collateral,
    address indexed principal,
    address indexed user,
    uint256 debtToCover,
    uint256 liquidatedCollateralAmount,
    address liquidator,
    bool receiveAToken
  );

  /**
   * @dev Emitted when a reserve is disabled as collateral for an user
   * @param reserve The address of the reserve
   * @param user The address of the user
   **/
  event ReserveUsedAsCollateralDisabled(address indexed reserve, address indexed user);

  /**
   * @dev Emitted when a reserve is enabled as collateral for an user
   * @param reserve The address of the reserve
   * @param user The address of the user
   **/
  event ReserveUsedAsCollateralEnabled(address indexed reserve, address indexed user);

  /**
   * @dev Users can invoke this function to liquidate an undercollateralized position.
   * @param collateral The address of the collateral to liquidated
   * @param principal The address of the principal reserve
   * @param user The address of the borrower
   * @param debtToCover The amount of principal that the liquidator wants to repay
   * @param receiveAToken true if the liquidators wants to receive the aTokens, false if
   * he wants to receive the underlying asset directly
   **/
  function liquidationCall(
    address collateral,
    address principal,
    address user,
    uint256 debtToCover,
    bool receiveAToken
  ) external returns (uint256, string memory);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title VersionedInitializable
 *
 * @dev Helper contract to implement 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.
 *
 * @author Aave, inspired by the OpenZeppelin Initializable contract
 */
abstract contract VersionedInitializable {
  /**
   * @dev Indicates that the contract has been initialized.
   */
  uint256 private lastInitializedRevision = 0;

  /**
   * @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() {
    uint256 revision = getRevision();
    require(
      initializing || isConstructor() || revision > lastInitializedRevision,
      'Contract instance has already been initialized'
    );

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

    _;

    if (isTopLevelCall) {
      initializing = false;
    }
  }

  /**
   * @dev returns the revision number of the contract
   * Needs to be defined in the inherited class as a constant.
   **/
  function getRevision() internal pure virtual returns (uint256);

  /**
   * @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.
    uint256 cs;
    //solium-disable-next-line
    assembly {
      cs := extcodesize(address())
    }
    return cs == 0;
  }

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

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {SafeMath} from '../../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IERC20} from '../../../dependencies/openzeppelin/contracts/IERC20.sol';
import {ReserveLogic} from './ReserveLogic.sol';
import {ReserveConfiguration} from '../configuration/ReserveConfiguration.sol';
import {UserConfiguration} from '../configuration/UserConfiguration.sol';
import {WadRayMath} from '../math/WadRayMath.sol';
import {PercentageMath} from '../math/PercentageMath.sol';
import {IPriceOracleGetter} from '../../../interfaces/IPriceOracleGetter.sol';
import {DataTypes} from '../types/DataTypes.sol';

/**
 * @title GenericLogic library
 * @author Aave
 * @title Implements protocol-level logic to calculate and validate the state of a user
 */
library GenericLogic {
  using ReserveLogic for DataTypes.ReserveData;
  using SafeMath for uint256;
  using WadRayMath for uint256;
  using PercentageMath for uint256;
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;
  using UserConfiguration for DataTypes.UserConfigurationMap;

  uint256 public constant HEALTH_FACTOR_LIQUIDATION_THRESHOLD = 1 ether;

  struct balanceDecreaseAllowedLocalVars {
    uint256 decimals;
    uint256 liquidationThreshold;
    uint256 totalCollateralInETH;
    uint256 totalDebtInETH;
    uint256 avgLiquidationThreshold;
    uint256 amountToDecreaseInETH;
    uint256 collateralBalanceAfterDecrease;
    uint256 liquidationThresholdAfterDecrease;
    uint256 healthFactorAfterDecrease;
    bool reserveUsageAsCollateralEnabled;
  }

  /**
   * @dev Checks if a specific balance decrease is allowed
   * (i.e. doesn't bring the user borrow position health factor under HEALTH_FACTOR_LIQUIDATION_THRESHOLD)
   * @param asset The address of the underlying asset of the reserve
   * @param user The address of the user
   * @param amount The amount to decrease
   * @param reservesData The data of all the reserves
   * @param userConfig The user configuration
   * @param reserves The list of all the active reserves
   * @param oracle The address of the oracle contract
   * @return true if the decrease of the balance is allowed
   **/
  function balanceDecreaseAllowed(
    address asset,
    address user,
    uint256 amount,
    mapping(address => DataTypes.ReserveData) storage reservesData,
    DataTypes.UserConfigurationMap calldata userConfig,
    mapping(uint256 => address) storage reserves,
    uint256 reservesCount,
    address oracle
  ) external view returns (bool) {
    if (!userConfig.isBorrowingAny() || !userConfig.isUsingAsCollateral(reservesData[asset].id)) {
      return true;
    }

    balanceDecreaseAllowedLocalVars memory vars;

    (, vars.liquidationThreshold, , vars.decimals, ) = reservesData[asset]
      .configuration
      .getParams();

    if (vars.liquidationThreshold == 0) {
      return true;
    }

    (
      vars.totalCollateralInETH,
      vars.totalDebtInETH,
      ,
      vars.avgLiquidationThreshold,

    ) = calculateUserAccountData(user, reservesData, userConfig, reserves, reservesCount, oracle);

    if (vars.totalDebtInETH == 0) {
      return true;
    }

    vars.amountToDecreaseInETH = IPriceOracleGetter(oracle).getAssetPrice(asset).mul(amount).div(
      10**vars.decimals
    );

    vars.collateralBalanceAfterDecrease = vars.totalCollateralInETH.sub(vars.amountToDecreaseInETH);

    //if there is a borrow, there can't be 0 collateral
    if (vars.collateralBalanceAfterDecrease == 0) {
      return false;
    }

    vars.liquidationThresholdAfterDecrease = vars
      .totalCollateralInETH
      .mul(vars.avgLiquidationThreshold)
      .sub(vars.amountToDecreaseInETH.mul(vars.liquidationThreshold))
      .div(vars.collateralBalanceAfterDecrease);

    uint256 healthFactorAfterDecrease =
      calculateHealthFactorFromBalances(
        vars.collateralBalanceAfterDecrease,
        vars.totalDebtInETH,
        vars.liquidationThresholdAfterDecrease
      );

    return healthFactorAfterDecrease >= GenericLogic.HEALTH_FACTOR_LIQUIDATION_THRESHOLD;
  }

  struct CalculateUserAccountDataVars {
    uint256 reserveUnitPrice;
    uint256 tokenUnit;
    uint256 compoundedLiquidityBalance;
    uint256 compoundedBorrowBalance;
    uint256 decimals;
    uint256 ltv;
    uint256 liquidationThreshold;
    uint256 i;
    uint256 healthFactor;
    uint256 totalCollateralInETH;
    uint256 totalDebtInETH;
    uint256 avgLtv;
    uint256 avgLiquidationThreshold;
    uint256 reservesLength;
    bool healthFactorBelowThreshold;
    address currentReserveAddress;
    bool usageAsCollateralEnabled;
    bool userUsesReserveAsCollateral;
  }

  /**
   * @dev Calculates the user data across the reserves.
   * this includes the total liquidity/collateral/borrow balances in ETH,
   * the average Loan To Value, the average Liquidation Ratio, and the Health factor.
   * @param user The address of the user
   * @param reservesData Data of all the reserves
   * @param userConfig The configuration of the user
   * @param reserves The list of the available reserves
   * @param oracle The price oracle address
   * @return The total collateral and total debt of the user in ETH, the avg ltv, liquidation threshold and the HF
   **/
  function calculateUserAccountData(
    address user,
    mapping(address => DataTypes.ReserveData) storage reservesData,
    DataTypes.UserConfigurationMap memory userConfig,
    mapping(uint256 => address) storage reserves,
    uint256 reservesCount,
    address oracle
  )
    internal
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      uint256
    )
  {
    CalculateUserAccountDataVars memory vars;

    if (userConfig.isEmpty()) {
      return (0, 0, 0, 0, uint256(-1));
    }
    for (vars.i = 0; vars.i < reservesCount; vars.i++) {
      if (!userConfig.isUsingAsCollateralOrBorrowing(vars.i)) {
        continue;
      }

      vars.currentReserveAddress = reserves[vars.i];
      DataTypes.ReserveData storage currentReserve = reservesData[vars.currentReserveAddress];

      (vars.ltv, vars.liquidationThreshold, , vars.decimals, ) = currentReserve
        .configuration
        .getParams();

      vars.tokenUnit = 10**vars.decimals;
      vars.reserveUnitPrice = IPriceOracleGetter(oracle).getAssetPrice(vars.currentReserveAddress);

      if (vars.liquidationThreshold != 0 && userConfig.isUsingAsCollateral(vars.i)) {
        vars.compoundedLiquidityBalance = IERC20(currentReserve.aTokenAddress).balanceOf(user);

        uint256 liquidityBalanceETH =
          vars.reserveUnitPrice.mul(vars.compoundedLiquidityBalance).div(vars.tokenUnit);

        vars.totalCollateralInETH = vars.totalCollateralInETH.add(liquidityBalanceETH);

        vars.avgLtv = vars.avgLtv.add(liquidityBalanceETH.mul(vars.ltv));
        vars.avgLiquidationThreshold = vars.avgLiquidationThreshold.add(
          liquidityBalanceETH.mul(vars.liquidationThreshold)
        );
      }

      if (userConfig.isBorrowing(vars.i)) {
        vars.compoundedBorrowBalance = IERC20(currentReserve.stableDebtTokenAddress).balanceOf(
          user
        );
        vars.compoundedBorrowBalance = vars.compoundedBorrowBalance.add(
          IERC20(currentReserve.variableDebtTokenAddress).balanceOf(user)
        );

        vars.totalDebtInETH = vars.totalDebtInETH.add(
          vars.reserveUnitPrice.mul(vars.compoundedBorrowBalance).div(vars.tokenUnit)
        );
      }
    }

    vars.avgLtv = vars.totalCollateralInETH > 0 ? vars.avgLtv.div(vars.totalCollateralInETH) : 0;
    vars.avgLiquidationThreshold = vars.totalCollateralInETH > 0
      ? vars.avgLiquidationThreshold.div(vars.totalCollateralInETH)
      : 0;

    vars.healthFactor = calculateHealthFactorFromBalances(
      vars.totalCollateralInETH,
      vars.totalDebtInETH,
      vars.avgLiquidationThreshold
    );
    return (
      vars.totalCollateralInETH,
      vars.totalDebtInETH,
      vars.avgLtv,
      vars.avgLiquidationThreshold,
      vars.healthFactor
    );
  }

  /**
   * @dev Calculates the health factor from the corresponding balances
   * @param totalCollateralInETH The total collateral in ETH
   * @param totalDebtInETH The total debt in ETH
   * @param liquidationThreshold The avg liquidation threshold
   * @return The health factor calculated from the balances provided
   **/
  function calculateHealthFactorFromBalances(
    uint256 totalCollateralInETH,
    uint256 totalDebtInETH,
    uint256 liquidationThreshold
  ) internal pure returns (uint256) {
    if (totalDebtInETH == 0) return uint256(-1);

    return (totalCollateralInETH.percentMul(liquidationThreshold)).wadDiv(totalDebtInETH);
  }

  /**
   * @dev Calculates the equivalent amount in ETH that an user can borrow, depending on the available collateral and the
   * average Loan To Value
   * @param totalCollateralInETH The total collateral in ETH
   * @param totalDebtInETH The total borrow balance
   * @param ltv The average loan to value
   * @return the amount available to borrow in ETH for the user
   **/

  function calculateAvailableBorrowsETH(
    uint256 totalCollateralInETH,
    uint256 totalDebtInETH,
    uint256 ltv
  ) internal pure returns (uint256) {
    uint256 availableBorrowsETH = totalCollateralInETH.percentMul(ltv);

    if (availableBorrowsETH < totalDebtInETH) {
      return 0;
    }

    availableBorrowsETH = availableBorrowsETH.sub(totalDebtInETH);
    return availableBorrowsETH;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IERC20} from '../../../dependencies/openzeppelin/contracts/IERC20.sol';
import {DataTypes} from '../types/DataTypes.sol';

/**
 * @title Helpers library
 * @author Aave
 */
library Helpers {
  /**
   * @dev Fetches the user current stable and variable debt balances
   * @param user The user address
   * @param reserve The reserve data object
   * @return The stable and variable debt balance
   **/
  function getUserCurrentDebt(address user, DataTypes.ReserveData storage reserve)
    internal
    view
    returns (uint256, uint256)
  {
    return (
      IERC20(reserve.stableDebtTokenAddress).balanceOf(user),
      IERC20(reserve.variableDebtTokenAddress).balanceOf(user)
    );
  }

  function getUserCurrentDebtMemory(address user, DataTypes.ReserveData memory reserve)
    internal
    view
    returns (uint256, uint256)
  {
    return (
      IERC20(reserve.stableDebtTokenAddress).balanceOf(user),
      IERC20(reserve.variableDebtTokenAddress).balanceOf(user)
    );
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {Errors} from '../helpers/Errors.sol';

/**
 * @title WadRayMath library
 * @author Aave
 * @dev Provides mul and div function for wads (decimal numbers with 18 digits precision) and rays (decimals with 27 digits)
 **/

library WadRayMath {
  uint256 internal constant WAD = 1e18;
  uint256 internal constant halfWAD = WAD / 2;

  uint256 internal constant RAY = 1e27;
  uint256 internal constant halfRAY = RAY / 2;

  uint256 internal constant WAD_RAY_RATIO = 1e9;

  /**
   * @return One ray, 1e27
   **/
  function ray() internal pure returns (uint256) {
    return RAY;
  }

  /**
   * @return One wad, 1e18
   **/

  function wad() internal pure returns (uint256) {
    return WAD;
  }

  /**
   * @return Half ray, 1e27/2
   **/
  function halfRay() internal pure returns (uint256) {
    return halfRAY;
  }

  /**
   * @return Half ray, 1e18/2
   **/
  function halfWad() internal pure returns (uint256) {
    return halfWAD;
  }

  /**
   * @dev Multiplies two wad, rounding half up to the nearest wad
   * @param a Wad
   * @param b Wad
   * @return The result of a*b, in wad
   **/
  function wadMul(uint256 a, uint256 b) internal pure returns (uint256) {
    if (a == 0 || b == 0) {
      return 0;
    }

    require(a <= (type(uint256).max - halfWAD) / b, Errors.MATH_MULTIPLICATION_OVERFLOW);

    return (a * b + halfWAD) / WAD;
  }

  /**
   * @dev Divides two wad, rounding half up to the nearest wad
   * @param a Wad
   * @param b Wad
   * @return The result of a/b, in wad
   **/
  function wadDiv(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b != 0, Errors.MATH_DIVISION_BY_ZERO);
    uint256 halfB = b / 2;

    require(a <= (type(uint256).max - halfB) / WAD, Errors.MATH_MULTIPLICATION_OVERFLOW);

    return (a * WAD + halfB) / b;
  }

  /**
   * @dev Multiplies two ray, rounding half up to the nearest ray
   * @param a Ray
   * @param b Ray
   * @return The result of a*b, in ray
   **/
  function rayMul(uint256 a, uint256 b) internal pure returns (uint256) {
    if (a == 0 || b == 0) {
      return 0;
    }

    require(a <= (type(uint256).max - halfRAY) / b, Errors.MATH_MULTIPLICATION_OVERFLOW);

    return (a * b + halfRAY) / RAY;
  }

  /**
   * @dev Divides two ray, rounding half up to the nearest ray
   * @param a Ray
   * @param b Ray
   * @return The result of a/b, in ray
   **/
  function rayDiv(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b != 0, Errors.MATH_DIVISION_BY_ZERO);
    uint256 halfB = b / 2;

    require(a <= (type(uint256).max - halfB) / RAY, Errors.MATH_MULTIPLICATION_OVERFLOW);

    return (a * RAY + halfB) / b;
  }

  /**
   * @dev Casts ray down to wad
   * @param a Ray
   * @return a casted to wad, rounded half up to the nearest wad
   **/
  function rayToWad(uint256 a) internal pure returns (uint256) {
    uint256 halfRatio = WAD_RAY_RATIO / 2;
    uint256 result = halfRatio + a;
    require(result >= halfRatio, Errors.MATH_ADDITION_OVERFLOW);

    return result / WAD_RAY_RATIO;
  }

  /**
   * @dev Converts wad up to ray
   * @param a Wad
   * @return a converted in ray
   **/
  function wadToRay(uint256 a) internal pure returns (uint256) {
    uint256 result = a * WAD_RAY_RATIO;
    require(result / WAD_RAY_RATIO == a, Errors.MATH_MULTIPLICATION_OVERFLOW);
    return result;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {SafeMath} from '../../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IERC20} from '../../../dependencies/openzeppelin/contracts/IERC20.sol';
import {ReserveLogic} from './ReserveLogic.sol';
import {GenericLogic} from './GenericLogic.sol';
import {WadRayMath} from '../math/WadRayMath.sol';
import {PercentageMath} from '../math/PercentageMath.sol';
import {SafeERC20} from '../../../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {ReserveConfiguration} from '../configuration/ReserveConfiguration.sol';
import {UserConfiguration} from '../configuration/UserConfiguration.sol';
import {Errors} from '../helpers/Errors.sol';
import {Helpers} from '../helpers/Helpers.sol';
import {IReserveInterestRateStrategy} from '../../../interfaces/IReserveInterestRateStrategy.sol';
import {DataTypes} from '../types/DataTypes.sol';

/**
 * @title ReserveLogic library
 * @author Aave
 * @notice Implements functions to validate the different actions of the protocol
 */
library ValidationLogic {
  using ReserveLogic for DataTypes.ReserveData;
  using SafeMath for uint256;
  using WadRayMath for uint256;
  using PercentageMath for uint256;
  using SafeERC20 for IERC20;
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;
  using UserConfiguration for DataTypes.UserConfigurationMap;

  uint256 public constant REBALANCE_UP_LIQUIDITY_RATE_THRESHOLD = 4000;
  uint256 public constant REBALANCE_UP_USAGE_RATIO_THRESHOLD = 0.95 * 1e27; //usage ratio of 95%

  /**
   * @dev Validates a deposit action
   * @param reserve The reserve object on which the user is depositing
   * @param amount The amount to be deposited
   */
  function validateDeposit(DataTypes.ReserveData storage reserve, uint256 amount) external view {
    (bool isActive, bool isFrozen, , ) = reserve.configuration.getFlags();

    require(amount != 0, Errors.VL_INVALID_AMOUNT);
    require(isActive, Errors.VL_NO_ACTIVE_RESERVE);
    require(!isFrozen, Errors.VL_RESERVE_FROZEN);
  }

  /**
   * @dev Validates a withdraw action
   * @param reserveAddress The address of the reserve
   * @param amount The amount to be withdrawn
   * @param userBalance The balance of the user
   * @param reservesData The reserves state
   * @param userConfig The user configuration
   * @param reserves The addresses of the reserves
   * @param reservesCount The number of reserves
   * @param oracle The price oracle
   */
  function validateWithdraw(
    address reserveAddress,
    uint256 amount,
    uint256 userBalance,
    mapping(address => DataTypes.ReserveData) storage reservesData,
    DataTypes.UserConfigurationMap storage userConfig,
    mapping(uint256 => address) storage reserves,
    uint256 reservesCount,
    address oracle
  ) external view {
    require(amount != 0, Errors.VL_INVALID_AMOUNT);
    require(amount <= userBalance, Errors.VL_NOT_ENOUGH_AVAILABLE_USER_BALANCE);

    (bool isActive, , , ) = reservesData[reserveAddress].configuration.getFlags();
    require(isActive, Errors.VL_NO_ACTIVE_RESERVE);

    require(
      GenericLogic.balanceDecreaseAllowed(
        reserveAddress,
        msg.sender,
        amount,
        reservesData,
        userConfig,
        reserves,
        reservesCount,
        oracle
      ),
      Errors.VL_TRANSFER_NOT_ALLOWED
    );
  }

  struct ValidateBorrowLocalVars {
    uint256 currentLtv;
    uint256 currentLiquidationThreshold;
    uint256 amountOfCollateralNeededETH;
    uint256 userCollateralBalanceETH;
    uint256 userBorrowBalanceETH;
    uint256 availableLiquidity;
    uint256 healthFactor;
    bool isActive;
    bool isFrozen;
    bool borrowingEnabled;
    bool stableRateBorrowingEnabled;
  }

  /**
   * @dev Validates a borrow action
   * @param asset The address of the asset to borrow
   * @param reserve The reserve state from which the user is borrowing
   * @param userAddress The address of the user
   * @param amount The amount to be borrowed
   * @param amountInETH The amount to be borrowed, in ETH
   * @param interestRateMode The interest rate mode at which the user is borrowing
   * @param maxStableLoanPercent The max amount of the liquidity that can be borrowed at stable rate, in percentage
   * @param reservesData The state of all the reserves
   * @param userConfig The state of the user for the specific reserve
   * @param reserves The addresses of all the active reserves
   * @param oracle The price oracle
   */

  function validateBorrow(
    address asset,
    DataTypes.ReserveData storage reserve,
    address userAddress,
    uint256 amount,
    uint256 amountInETH,
    uint256 interestRateMode,
    uint256 maxStableLoanPercent,
    mapping(address => DataTypes.ReserveData) storage reservesData,
    DataTypes.UserConfigurationMap storage userConfig,
    mapping(uint256 => address) storage reserves,
    uint256 reservesCount,
    address oracle
  ) external view {
    ValidateBorrowLocalVars memory vars;

    (vars.isActive, vars.isFrozen, vars.borrowingEnabled, vars.stableRateBorrowingEnabled) = reserve
      .configuration
      .getFlags();

    require(vars.isActive, Errors.VL_NO_ACTIVE_RESERVE);
    require(!vars.isFrozen, Errors.VL_RESERVE_FROZEN);
    require(amount != 0, Errors.VL_INVALID_AMOUNT);

    require(vars.borrowingEnabled, Errors.VL_BORROWING_NOT_ENABLED);

    //validate interest rate mode
    require(
      uint256(DataTypes.InterestRateMode.VARIABLE) == interestRateMode ||
        uint256(DataTypes.InterestRateMode.STABLE) == interestRateMode,
      Errors.VL_INVALID_INTEREST_RATE_MODE_SELECTED
    );

    (
      vars.userCollateralBalanceETH,
      vars.userBorrowBalanceETH,
      vars.currentLtv,
      vars.currentLiquidationThreshold,
      vars.healthFactor
    ) = GenericLogic.calculateUserAccountData(
      userAddress,
      reservesData,
      userConfig,
      reserves,
      reservesCount,
      oracle
    );

    require(vars.userCollateralBalanceETH > 0, Errors.VL_COLLATERAL_BALANCE_IS_0);

    require(
      vars.healthFactor > GenericLogic.HEALTH_FACTOR_LIQUIDATION_THRESHOLD,
      Errors.VL_HEALTH_FACTOR_LOWER_THAN_LIQUIDATION_THRESHOLD
    );

    //add the current already borrowed amount to the amount requested to calculate the total collateral needed.
    vars.amountOfCollateralNeededETH = vars.userBorrowBalanceETH.add(amountInETH).percentDiv(
      vars.currentLtv
    ); //LTV is calculated in percentage

    require(
      vars.amountOfCollateralNeededETH <= vars.userCollateralBalanceETH,
      Errors.VL_COLLATERAL_CANNOT_COVER_NEW_BORROW
    );

    /**
     * Following conditions need to be met if the user is borrowing at a stable rate:
     * 1. Reserve must be enabled for stable rate borrowing
     * 2. Users cannot borrow from the reserve if their collateral is (mostly) the same currency
     *    they are borrowing, to prevent abuses.
     * 3. Users will be able to borrow only a portion of the total available liquidity
     **/

    if (interestRateMode == uint256(DataTypes.InterestRateMode.STABLE)) {
      //check if the borrow mode is stable and if stable rate borrowing is enabled on this reserve

      require(vars.stableRateBorrowingEnabled, Errors.VL_STABLE_BORROWING_NOT_ENABLED);

      require(
        !userConfig.isUsingAsCollateral(reserve.id) ||
          reserve.configuration.getLtv() == 0 ||
          amount > IERC20(reserve.aTokenAddress).balanceOf(userAddress),
        Errors.VL_COLLATERAL_SAME_AS_BORROWING_CURRENCY
      );

      vars.availableLiquidity = IERC20(asset).balanceOf(reserve.aTokenAddress);

      //calculate the max available loan size in stable rate mode as a percentage of the
      //available liquidity
      uint256 maxLoanSizeStable = vars.availableLiquidity.percentMul(maxStableLoanPercent);

      require(amount <= maxLoanSizeStable, Errors.VL_AMOUNT_BIGGER_THAN_MAX_LOAN_SIZE_STABLE);
    }
  }

  /**
   * @dev Validates a repay action
   * @param reserve The reserve state from which the user is repaying
   * @param amountSent The amount sent for the repayment. Can be an actual value or uint(-1)
   * @param onBehalfOf The address of the user msg.sender is repaying for
   * @param stableDebt The borrow balance of the user
   * @param variableDebt The borrow balance of the user
   */
  function validateRepay(
    DataTypes.ReserveData storage reserve,
    uint256 amountSent,
    DataTypes.InterestRateMode rateMode,
    address onBehalfOf,
    uint256 stableDebt,
    uint256 variableDebt
  ) external view {
    bool isActive = reserve.configuration.getActive();

    require(isActive, Errors.VL_NO_ACTIVE_RESERVE);

    require(amountSent > 0, Errors.VL_INVALID_AMOUNT);

    require(
      (stableDebt > 0 &&
        DataTypes.InterestRateMode(rateMode) == DataTypes.InterestRateMode.STABLE) ||
        (variableDebt > 0 &&
          DataTypes.InterestRateMode(rateMode) == DataTypes.InterestRateMode.VARIABLE),
      Errors.VL_NO_DEBT_OF_SELECTED_TYPE
    );

    require(
      amountSent != uint256(-1) || msg.sender == onBehalfOf,
      Errors.VL_NO_EXPLICIT_AMOUNT_TO_REPAY_ON_BEHALF
    );
  }

  /**
   * @dev Validates a swap of borrow rate mode.
   * @param reserve The reserve state on which the user is swapping the rate
   * @param userConfig The user reserves configuration
   * @param stableDebt The stable debt of the user
   * @param variableDebt The variable debt of the user
   * @param currentRateMode The rate mode of the borrow
   */
  function validateSwapRateMode(
    DataTypes.ReserveData storage reserve,
    DataTypes.UserConfigurationMap storage userConfig,
    uint256 stableDebt,
    uint256 variableDebt,
    DataTypes.InterestRateMode currentRateMode
  ) external view {
    (bool isActive, bool isFrozen, , bool stableRateEnabled) = reserve.configuration.getFlags();

    require(isActive, Errors.VL_NO_ACTIVE_RESERVE);
    require(!isFrozen, Errors.VL_RESERVE_FROZEN);

    if (currentRateMode == DataTypes.InterestRateMode.STABLE) {
      require(stableDebt > 0, Errors.VL_NO_STABLE_RATE_LOAN_IN_RESERVE);
    } else if (currentRateMode == DataTypes.InterestRateMode.VARIABLE) {
      require(variableDebt > 0, Errors.VL_NO_VARIABLE_RATE_LOAN_IN_RESERVE);
      /**
       * user wants to swap to stable, before swapping we need to ensure that
       * 1. stable borrow rate is enabled on the reserve
       * 2. user is not trying to abuse the reserve by depositing
       * more collateral than he is borrowing, artificially lowering
       * the interest rate, borrowing at variable, and switching to stable
       **/
      require(stableRateEnabled, Errors.VL_STABLE_BORROWING_NOT_ENABLED);

      require(
        !userConfig.isUsingAsCollateral(reserve.id) ||
          reserve.configuration.getLtv() == 0 ||
          stableDebt.add(variableDebt) > IERC20(reserve.aTokenAddress).balanceOf(msg.sender),
        Errors.VL_COLLATERAL_SAME_AS_BORROWING_CURRENCY
      );
    } else {
      revert(Errors.VL_INVALID_INTEREST_RATE_MODE_SELECTED);
    }
  }

  /**
   * @dev Validates a stable borrow rate rebalance action
   * @param reserve The reserve state on which the user is getting rebalanced
   * @param reserveAddress The address of the reserve
   * @param stableDebtToken The stable debt token instance
   * @param variableDebtToken The variable debt token instance
   * @param aTokenAddress The address of the aToken contract
   */
  function validateRebalanceStableBorrowRate(
    DataTypes.ReserveData storage reserve,
    address reserveAddress,
    IERC20 stableDebtToken,
    IERC20 variableDebtToken,
    address aTokenAddress
  ) external view {
    (bool isActive, , , ) = reserve.configuration.getFlags();

    require(isActive, Errors.VL_NO_ACTIVE_RESERVE);

    //if the usage ratio is below 95%, no rebalances are needed
    uint256 totalDebt =
      stableDebtToken.totalSupply().add(variableDebtToken.totalSupply()).wadToRay();
    uint256 availableLiquidity = IERC20(reserveAddress).balanceOf(aTokenAddress).wadToRay();
    uint256 usageRatio = totalDebt == 0 ? 0 : totalDebt.rayDiv(availableLiquidity.add(totalDebt));

    //if the liquidity rate is below REBALANCE_UP_THRESHOLD of the max variable APR at 95% usage,
    //then we allow rebalancing of the stable rate positions.

    uint256 currentLiquidityRate = reserve.currentLiquidityRate;
    uint256 maxVariableBorrowRate =
      IReserveInterestRateStrategy(reserve.interestRateStrategyAddress).getMaxVariableBorrowRate();

    require(
      usageRatio >= REBALANCE_UP_USAGE_RATIO_THRESHOLD &&
        currentLiquidityRate <=
        maxVariableBorrowRate.percentMul(REBALANCE_UP_LIQUIDITY_RATE_THRESHOLD),
      Errors.LP_INTEREST_RATE_REBALANCE_CONDITIONS_NOT_MET
    );
  }

  /**
   * @dev Validates the action of setting an asset as collateral
   * @param reserve The state of the reserve that the user is enabling or disabling as collateral
   * @param reserveAddress The address of the reserve
   * @param reservesData The data of all the reserves
   * @param userConfig The state of the user for the specific reserve
   * @param reserves The addresses of all the active reserves
   * @param oracle The price oracle
   */
  function validateSetUseReserveAsCollateral(
    DataTypes.ReserveData storage reserve,
    address reserveAddress,
    bool useAsCollateral,
    mapping(address => DataTypes.ReserveData) storage reservesData,
    DataTypes.UserConfigurationMap storage userConfig,
    mapping(uint256 => address) storage reserves,
    uint256 reservesCount,
    address oracle
  ) external view {
    uint256 underlyingBalance = IERC20(reserve.aTokenAddress).balanceOf(msg.sender);

    require(underlyingBalance > 0, Errors.VL_UNDERLYING_BALANCE_NOT_GREATER_THAN_0);

    require(
      useAsCollateral ||
        GenericLogic.balanceDecreaseAllowed(
          reserveAddress,
          msg.sender,
          underlyingBalance,
          reservesData,
          userConfig,
          reserves,
          reservesCount,
          oracle
        ),
      Errors.VL_DEPOSIT_ALREADY_IN_USE
    );
  }

  /**
   * @dev Validates a flashloan action
   * @param assets The assets being flashborrowed
   * @param amounts The amounts for each asset being borrowed
   **/
  function validateFlashloan(address[] memory assets, uint256[] memory amounts) internal pure {
    require(assets.length == amounts.length, Errors.VL_INCONSISTENT_FLASHLOAN_PARAMS);
  }

  /**
   * @dev Validates the liquidation action
   * @param collateralReserve The reserve data of the collateral
   * @param principalReserve The reserve data of the principal
   * @param userConfig The user configuration
   * @param userHealthFactor The user's health factor
   * @param userStableDebt Total stable debt balance of the user
   * @param userVariableDebt Total variable debt balance of the user
   **/
  function validateLiquidationCall(
    DataTypes.ReserveData storage collateralReserve,
    DataTypes.ReserveData storage principalReserve,
    DataTypes.UserConfigurationMap storage userConfig,
    uint256 userHealthFactor,
    uint256 userStableDebt,
    uint256 userVariableDebt
  ) internal view returns (uint256, string memory) {
    if (
      !collateralReserve.configuration.getActive() || !principalReserve.configuration.getActive()
    ) {
      return (
        uint256(Errors.CollateralManagerErrors.NO_ACTIVE_RESERVE),
        Errors.VL_NO_ACTIVE_RESERVE
      );
    }

    if (userHealthFactor >= GenericLogic.HEALTH_FACTOR_LIQUIDATION_THRESHOLD) {
      return (
        uint256(Errors.CollateralManagerErrors.HEALTH_FACTOR_ABOVE_THRESHOLD),
        Errors.LPCM_HEALTH_FACTOR_NOT_BELOW_THRESHOLD
      );
    }

    bool isCollateralEnabled =
      collateralReserve.configuration.getLiquidationThreshold() > 0 &&
        userConfig.isUsingAsCollateral(collateralReserve.id);

    //if collateral isn't enabled as collateral by user, it cannot be liquidated
    if (!isCollateralEnabled) {
      return (
        uint256(Errors.CollateralManagerErrors.COLLATERAL_CANNOT_BE_LIQUIDATED),
        Errors.LPCM_COLLATERAL_CANNOT_BE_LIQUIDATED
      );
    }

    if (userStableDebt == 0 && userVariableDebt == 0) {
      return (
        uint256(Errors.CollateralManagerErrors.CURRRENCY_NOT_BORROWED),
        Errors.LPCM_SPECIFIED_CURRENCY_NOT_BORROWED_BY_USER
      );
    }

    return (uint256(Errors.CollateralManagerErrors.NO_ERROR), Errors.LPCM_NO_ERRORS);
  }

  /**
   * @dev Validates an aToken transfer
   * @param from The user from which the aTokens are being transferred
   * @param reservesData The state of all the reserves
   * @param userConfig The state of the user for the specific reserve
   * @param reserves The addresses of all the active reserves
   * @param oracle The price oracle
   */
  function validateTransfer(
    address from,
    mapping(address => DataTypes.ReserveData) storage reservesData,
    DataTypes.UserConfigurationMap storage userConfig,
    mapping(uint256 => address) storage reserves,
    uint256 reservesCount,
    address oracle
  ) internal view {
    (, , , , uint256 healthFactor) =
      GenericLogic.calculateUserAccountData(
        from,
        reservesData,
        userConfig,
        reserves,
        reservesCount,
        oracle
      );

    require(
      healthFactor >= GenericLogic.HEALTH_FACTOR_LIQUIDATION_THRESHOLD,
      Errors.VL_TRANSFER_NOT_ALLOWED
    );
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {UserConfiguration} from '../libraries/configuration/UserConfiguration.sol';
import {ReserveConfiguration} from '../libraries/configuration/ReserveConfiguration.sol';
import {ReserveLogic} from '../libraries/logic/ReserveLogic.sol';
import {ILendingPoolAddressesProvider} from '../../interfaces/ILendingPoolAddressesProvider.sol';
import {DataTypes} from '../libraries/types/DataTypes.sol';

contract LendingPoolStorage {
  using ReserveLogic for DataTypes.ReserveData;
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;
  using UserConfiguration for DataTypes.UserConfigurationMap;

  ILendingPoolAddressesProvider internal _addressesProvider;

  mapping(address => DataTypes.ReserveData) internal _reserves;
  mapping(address => DataTypes.UserConfigurationMap) internal _usersConfig;

  // the list of the available reserves, structured as a mapping for gas savings reasons
  mapping(uint256 => address) internal _reservesList;

  uint256 internal _reservesCount;

  bool internal _paused;

  uint256 internal _maxStableRateBorrowSizePercent;

  uint256 internal _flashLoanPremiumTotal;

  uint256 internal _maxNumberOfReserves;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

interface IScaledBalanceToken {
  /**
   * @dev Returns the scaled balance of the user. The scaled balance is the sum of all the
   * updated stored balance divided by the reserve's liquidity index at the moment of the update
   * @param user The user whose balance is calculated
   * @return The scaled balance of the user
   **/
  function scaledBalanceOf(address user) external view returns (uint256);

  /**
   * @dev Returns the scaled balance of the user and the scaled total supply.
   * @param user The address of the user
   * @return The scaled balance of the user
   * @return The scaled balance and the scaled total supply
   **/
  function getScaledUserBalanceAndSupply(address user) external view returns (uint256, uint256);

  /**
   * @dev Returns the scaled total supply of the variable debt token. Represents sum(debt/index)
   * @return The scaled total supply
   **/
  function scaledTotalSupply() external view returns (uint256);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {ILendingPool} from './ILendingPool.sol';
import {IAaveIncentivesController} from './IAaveIncentivesController.sol';

/**
 * @title IInitializableAToken
 * @notice Interface for the initialize function on AToken
 * @author Aave
 **/
interface IInitializableAToken {
  /**
   * @dev Emitted when an aToken is initialized
   * @param underlyingAsset The address of the underlying asset
   * @param pool The address of the associated lending pool
   * @param treasury The address of the treasury
   * @param incentivesController The address of the incentives controller for this aToken
   * @param aTokenDecimals the decimals of the underlying
   * @param aTokenName the name of the aToken
   * @param aTokenSymbol the symbol of the aToken
   * @param params A set of encoded parameters for additional initialization
   **/
  event Initialized(
    address indexed underlyingAsset,
    address indexed pool,
    address treasury,
    address incentivesController,
    uint8 aTokenDecimals,
    string aTokenName,
    string aTokenSymbol,
    bytes params
  );

  /**
   * @dev Initializes the aToken
   * @param pool The address of the lending pool where this aToken will be used
   * @param treasury The address of the Aave treasury, receiving the fees on this aToken
   * @param underlyingAsset The address of the underlying asset of this aToken (E.g. WETH for aWETH)
   * @param incentivesController The smart contract managing potential incentives distribution
   * @param aTokenDecimals The decimals of the aToken, same as the underlying asset's
   * @param aTokenName The name of the aToken
   * @param aTokenSymbol The symbol of the aToken
   */
  function initialize(
    ILendingPool pool,
    address treasury,
    address underlyingAsset,
    IAaveIncentivesController incentivesController,
    uint8 aTokenDecimals,
    string calldata aTokenName,
    string calldata aTokenSymbol,
    bytes calldata params
  ) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

interface IAaveIncentivesController {
  event RewardsAccrued(address indexed user, uint256 amount);

  event RewardsClaimed(address indexed user, address indexed to, uint256 amount);

  event RewardsClaimed(
    address indexed user,
    address indexed to,
    address indexed claimer,
    uint256 amount
  );

  event ClaimerSet(address indexed user, address indexed claimer);

  /*
   * @dev Returns the configuration of the distribution for a certain asset
   * @param asset The address of the reference asset of the distribution
   * @return The asset index, the emission per second and the last updated timestamp
   **/
  function getAssetData(address asset)
    external
    view
    returns (
      uint256,
      uint256,
      uint256
    );

  /**
   * @dev Whitelists an address to claim the rewards on behalf of another address
   * @param user The address of the user
   * @param claimer The address of the claimer
   */
  function setClaimer(address user, address claimer) external;

  /**
   * @dev Returns the whitelisted claimer for a certain address (0x0 if not set)
   * @param user The address of the user
   * @return The claimer address
   */
  function getClaimer(address user) external view returns (address);

  /**
   * @dev Configure assets for a certain rewards emission
   * @param assets The assets to incentivize
   * @param emissionsPerSecond The emission for each asset
   */
  function configureAssets(address[] calldata assets, uint256[] calldata emissionsPerSecond)
    external;

  /**
   * @dev Called by the corresponding asset on any update that affects the rewards distribution
   * @param asset The address of the user
   * @param userBalance The balance of the user of the asset in the lending pool
   * @param totalSupply The total supply of the asset in the lending pool
   **/
  function handleAction(
    address asset,
    uint256 userBalance,
    uint256 totalSupply
  ) external;

  /**
   * @dev Returns the total of rewards of an user, already accrued + not yet accrued
   * @param user The address of the user
   * @return The rewards
   **/
  function getRewardsBalance(address[] calldata assets, address user)
    external
    view
    returns (uint256);

  /**
   * @dev Claims reward for an user, on all the assets of the lending pool, accumulating the pending rewards
   * @param amount Amount of rewards to claim
   * @param to Address that will be receiving the rewards
   * @return Rewards claimed
   **/
  function claimRewards(
    address[] calldata assets,
    uint256 amount,
    address to
  ) external returns (uint256);

  /**
   * @dev Claims reward for an user on behalf, on all the assets of the lending pool, accumulating the pending rewards. The caller must
   * be whitelisted via "allowClaimOnBehalf" function by the RewardsAdmin role manager
   * @param amount Amount of rewards to claim
   * @param user Address to check and claim rewards
   * @param to Address that will be receiving the rewards
   * @return Rewards claimed
   **/
  function claimRewardsOnBehalf(
    address[] calldata assets,
    uint256 amount,
    address user,
    address to
  ) external returns (uint256);

  /**
   * @dev returns the unclaimed rewards of the user
   * @param user the address of the user
   * @return the unclaimed user rewards
   */
  function getUserUnclaimedRewards(address user) external view returns (uint256);

  /**
   * @dev returns the unclaimed rewards of the user
   * @param user the address of the user
   * @param asset The asset to incentivize
   * @return the user index for the asset
   */
  function getUserAssetData(address user, address asset) external view returns (uint256);

  /**
   * @dev for backward compatibility with previous implementation of the Incentives controller
   */
  function REWARD_TOKEN() external view returns (address);

  /**
   * @dev for backward compatibility with previous implementation of the Incentives controller
   */
  function PRECISION() external view returns (uint8);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {ILendingPool} from './ILendingPool.sol';
import {IAaveIncentivesController} from './IAaveIncentivesController.sol';

/**
 * @title IInitializableDebtToken
 * @notice Interface for the initialize function common between debt tokens
 * @author Aave
 **/
interface IInitializableDebtToken {
  /**
   * @dev Emitted when a debt token is initialized
   * @param underlyingAsset The address of the underlying asset
   * @param pool The address of the associated lending pool
   * @param incentivesController The address of the incentives controller for this aToken
   * @param debtTokenDecimals the decimals of the debt token
   * @param debtTokenName the name of the debt token
   * @param debtTokenSymbol the symbol of the debt token
   * @param params A set of encoded parameters for additional initialization
   **/
  event Initialized(
    address indexed underlyingAsset,
    address indexed pool,
    address incentivesController,
    uint8 debtTokenDecimals,
    string debtTokenName,
    string debtTokenSymbol,
    bytes params
  );

  /**
   * @dev Initializes the debt token.
   * @param pool The address of the lending pool where this aToken will be used
   * @param underlyingAsset The address of the underlying asset of this aToken (E.g. WETH for aWETH)
   * @param incentivesController The smart contract managing potential incentives distribution
   * @param debtTokenDecimals The decimals of the debtToken, same as the underlying asset's
   * @param debtTokenName The name of the token
   * @param debtTokenSymbol The symbol of the token
   */
  function initialize(
    ILendingPool pool,
    address underlyingAsset,
    IAaveIncentivesController incentivesController,
    uint8 debtTokenDecimals,
    string memory debtTokenName,
    string memory debtTokenSymbol,
    bytes calldata params
  ) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {SafeMath} from '../../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IERC20} from '../../../dependencies/openzeppelin/contracts/IERC20.sol';
import {SafeERC20} from '../../../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {IAToken} from '../../../interfaces/IAToken.sol';
import {IStableDebtToken} from '../../../interfaces/IStableDebtToken.sol';
import {IVariableDebtToken} from '../../../interfaces/IVariableDebtToken.sol';
import {IReserveInterestRateStrategy} from '../../../interfaces/IReserveInterestRateStrategy.sol';
import {ReserveConfiguration} from '../configuration/ReserveConfiguration.sol';
import {MathUtils} from '../math/MathUtils.sol';
import {WadRayMath} from '../math/WadRayMath.sol';
import {PercentageMath} from '../math/PercentageMath.sol';
import {Errors} from '../helpers/Errors.sol';
import {DataTypes} from '../types/DataTypes.sol';

/**
 * @title ReserveLogic library
 * @author Aave
 * @notice Implements the logic to update the reserves state
 */
library ReserveLogic {
  using SafeMath for uint256;
  using WadRayMath for uint256;
  using PercentageMath for uint256;
  using SafeERC20 for IERC20;

  /**
   * @dev Emitted when the state of a reserve is updated
   * @param asset The address of the underlying asset of the reserve
   * @param liquidityRate The new liquidity rate
   * @param stableBorrowRate The new stable borrow rate
   * @param variableBorrowRate The new variable borrow rate
   * @param liquidityIndex The new liquidity index
   * @param variableBorrowIndex The new variable borrow index
   **/
  event ReserveDataUpdated(
    address indexed asset,
    uint256 liquidityRate,
    uint256 stableBorrowRate,
    uint256 variableBorrowRate,
    uint256 liquidityIndex,
    uint256 variableBorrowIndex
  );

  using ReserveLogic for DataTypes.ReserveData;
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;

  /**
   * @dev Returns the ongoing normalized income for the reserve
   * A value of 1e27 means there is no income. As time passes, the income is accrued
   * A value of 2*1e27 means for each unit of asset one unit of income has been accrued
   * @param reserve The reserve object
   * @return the normalized income. expressed in ray
   **/
  function getNormalizedIncome(DataTypes.ReserveData storage reserve)
    internal
    view
    returns (uint256)
  {
    uint40 timestamp = reserve.lastUpdateTimestamp;

    //solium-disable-next-line
    if (timestamp == uint40(block.timestamp)) {
      //if the index was updated in the same block, no need to perform any calculation
      return reserve.liquidityIndex;
    }

    uint256 cumulated =
      MathUtils.calculateLinearInterest(reserve.currentLiquidityRate, timestamp).rayMul(
        reserve.liquidityIndex
      );

    return cumulated;
  }

  /**
   * @dev Returns the ongoing normalized variable debt for the reserve
   * A value of 1e27 means there is no debt. As time passes, the income is accrued
   * A value of 2*1e27 means that for each unit of debt, one unit worth of interest has been accumulated
   * @param reserve The reserve object
   * @return The normalized variable debt. expressed in ray
   **/
  function getNormalizedDebt(DataTypes.ReserveData storage reserve)
    internal
    view
    returns (uint256)
  {
    uint40 timestamp = reserve.lastUpdateTimestamp;

    //solium-disable-next-line
    if (timestamp == uint40(block.timestamp)) {
      //if the index was updated in the same block, no need to perform any calculation
      return reserve.variableBorrowIndex;
    }

    uint256 cumulated =
      MathUtils.calculateCompoundedInterest(reserve.currentVariableBorrowRate, timestamp).rayMul(
        reserve.variableBorrowIndex
      );

    return cumulated;
  }

  /**
   * @dev Updates the liquidity cumulative index and the variable borrow index.
   * @param reserve the reserve object
   **/
  function updateState(DataTypes.ReserveData storage reserve) internal {
    uint256 scaledVariableDebt =
      IVariableDebtToken(reserve.variableDebtTokenAddress).scaledTotalSupply();
    uint256 previousVariableBorrowIndex = reserve.variableBorrowIndex;
    uint256 previousLiquidityIndex = reserve.liquidityIndex;
    uint40 lastUpdatedTimestamp = reserve.lastUpdateTimestamp;

    (uint256 newLiquidityIndex, uint256 newVariableBorrowIndex) =
      _updateIndexes(
        reserve,
        scaledVariableDebt,
        previousLiquidityIndex,
        previousVariableBorrowIndex,
        lastUpdatedTimestamp
      );

    _mintToTreasury(
      reserve,
      scaledVariableDebt,
      previousVariableBorrowIndex,
      newLiquidityIndex,
      newVariableBorrowIndex,
      lastUpdatedTimestamp
    );
  }

  /**
   * @dev Accumulates a predefined amount of asset to the reserve as a fixed, instantaneous income. Used for example to accumulate
   * the flashloan fee to the reserve, and spread it between all the depositors
   * @param reserve The reserve object
   * @param totalLiquidity The total liquidity available in the reserve
   * @param amount The amount to accomulate
   **/
  function cumulateToLiquidityIndex(
    DataTypes.ReserveData storage reserve,
    uint256 totalLiquidity,
    uint256 amount
  ) internal {
    uint256 amountToLiquidityRatio = amount.wadToRay().rayDiv(totalLiquidity.wadToRay());

    uint256 result = amountToLiquidityRatio.add(WadRayMath.ray());

    result = result.rayMul(reserve.liquidityIndex);
    require(result <= type(uint128).max, Errors.RL_LIQUIDITY_INDEX_OVERFLOW);

    reserve.liquidityIndex = uint128(result);
  }

  /**
   * @dev Initializes a reserve
   * @param reserve The reserve object
   * @param aTokenAddress The address of the overlying atoken contract
   * @param interestRateStrategyAddress The address of the interest rate strategy contract
   **/
  function init(
    DataTypes.ReserveData storage reserve,
    address aTokenAddress,
    address stableDebtTokenAddress,
    address variableDebtTokenAddress,
    address interestRateStrategyAddress
  ) external {
    require(reserve.aTokenAddress == address(0), Errors.RL_RESERVE_ALREADY_INITIALIZED);

    reserve.liquidityIndex = uint128(WadRayMath.ray());
    reserve.variableBorrowIndex = uint128(WadRayMath.ray());
    reserve.aTokenAddress = aTokenAddress;
    reserve.stableDebtTokenAddress = stableDebtTokenAddress;
    reserve.variableDebtTokenAddress = variableDebtTokenAddress;
    reserve.interestRateStrategyAddress = interestRateStrategyAddress;
  }

  struct UpdateInterestRatesLocalVars {
    address stableDebtTokenAddress;
    uint256 availableLiquidity;
    uint256 totalStableDebt;
    uint256 newLiquidityRate;
    uint256 newStableRate;
    uint256 newVariableRate;
    uint256 avgStableRate;
    uint256 totalVariableDebt;
  }

  /**
   * @dev Updates the reserve current stable borrow rate, the current variable borrow rate and the current liquidity rate
   * @param reserve The address of the reserve to be updated
   * @param liquidityAdded The amount of liquidity added to the protocol (deposit or repay) in the previous action
   * @param liquidityTaken The amount of liquidity taken from the protocol (redeem or borrow)
   **/
  function updateInterestRates(
    DataTypes.ReserveData storage reserve,
    address reserveAddress,
    address aTokenAddress,
    uint256 liquidityAdded,
    uint256 liquidityTaken
  ) internal {
    UpdateInterestRatesLocalVars memory vars;

    vars.stableDebtTokenAddress = reserve.stableDebtTokenAddress;

    (vars.totalStableDebt, vars.avgStableRate) = IStableDebtToken(vars.stableDebtTokenAddress)
      .getTotalSupplyAndAvgRate();

    //calculates the total variable debt locally using the scaled total supply instead
    //of totalSupply(), as it's noticeably cheaper. Also, the index has been
    //updated by the previous updateState() call
    vars.totalVariableDebt = IVariableDebtToken(reserve.variableDebtTokenAddress)
      .scaledTotalSupply()
      .rayMul(reserve.variableBorrowIndex);

    (
      vars.newLiquidityRate,
      vars.newStableRate,
      vars.newVariableRate
    ) = IReserveInterestRateStrategy(reserve.interestRateStrategyAddress).calculateInterestRates(
      reserveAddress,
      aTokenAddress,
      liquidityAdded,
      liquidityTaken,
      vars.totalStableDebt,
      vars.totalVariableDebt,
      vars.avgStableRate,
      reserve.configuration.getReserveFactor()
    );
    require(vars.newLiquidityRate <= type(uint128).max, Errors.RL_LIQUIDITY_RATE_OVERFLOW);
    require(vars.newStableRate <= type(uint128).max, Errors.RL_STABLE_BORROW_RATE_OVERFLOW);
    require(vars.newVariableRate <= type(uint128).max, Errors.RL_VARIABLE_BORROW_RATE_OVERFLOW);

    reserve.currentLiquidityRate = uint128(vars.newLiquidityRate);
    reserve.currentStableBorrowRate = uint128(vars.newStableRate);
    reserve.currentVariableBorrowRate = uint128(vars.newVariableRate);

    emit ReserveDataUpdated(
      reserveAddress,
      vars.newLiquidityRate,
      vars.newStableRate,
      vars.newVariableRate,
      reserve.liquidityIndex,
      reserve.variableBorrowIndex
    );
  }

  struct MintToTreasuryLocalVars {
    uint256 currentStableDebt;
    uint256 principalStableDebt;
    uint256 previousStableDebt;
    uint256 currentVariableDebt;
    uint256 previousVariableDebt;
    uint256 avgStableRate;
    uint256 cumulatedStableInterest;
    uint256 totalDebtAccrued;
    uint256 amountToMint;
    uint256 reserveFactor;
    uint40 stableSupplyUpdatedTimestamp;
  }

  /**
   * @dev Mints part of the repaid interest to the reserve treasury as a function of the reserveFactor for the
   * specific asset.
   * @param reserve The reserve reserve to be updated
   * @param scaledVariableDebt The current scaled total variable debt
   * @param previousVariableBorrowIndex The variable borrow index before the last accumulation of the interest
   * @param newLiquidityIndex The new liquidity index
   * @param newVariableBorrowIndex The variable borrow index after the last accumulation of the interest
   **/
  function _mintToTreasury(
    DataTypes.ReserveData storage reserve,
    uint256 scaledVariableDebt,
    uint256 previousVariableBorrowIndex,
    uint256 newLiquidityIndex,
    uint256 newVariableBorrowIndex,
    uint40 timestamp
  ) internal {
    MintToTreasuryLocalVars memory vars;

    vars.reserveFactor = reserve.configuration.getReserveFactor();

    if (vars.reserveFactor == 0) {
      return;
    }

    //fetching the principal, total stable debt and the avg stable rate
    (
      vars.principalStableDebt,
      vars.currentStableDebt,
      vars.avgStableRate,
      vars.stableSupplyUpdatedTimestamp
    ) = IStableDebtToken(reserve.stableDebtTokenAddress).getSupplyData();

    //calculate the last principal variable debt
    vars.previousVariableDebt = scaledVariableDebt.rayMul(previousVariableBorrowIndex);

    //calculate the new total supply after accumulation of the index
    vars.currentVariableDebt = scaledVariableDebt.rayMul(newVariableBorrowIndex);

    //calculate the stable debt until the last timestamp update
    vars.cumulatedStableInterest = MathUtils.calculateCompoundedInterest(
      vars.avgStableRate,
      vars.stableSupplyUpdatedTimestamp,
      timestamp
    );

    vars.previousStableDebt = vars.principalStableDebt.rayMul(vars.cumulatedStableInterest);

    //debt accrued is the sum of the current debt minus the sum of the debt at the last update
    vars.totalDebtAccrued = vars
      .currentVariableDebt
      .add(vars.currentStableDebt)
      .sub(vars.previousVariableDebt)
      .sub(vars.previousStableDebt);

    vars.amountToMint = vars.totalDebtAccrued.percentMul(vars.reserveFactor);

    if (vars.amountToMint != 0) {
      IAToken(reserve.aTokenAddress).mintToTreasury(vars.amountToMint, newLiquidityIndex);
    }
  }

  /**
   * @dev Updates the reserve indexes and the timestamp of the update
   * @param reserve The reserve reserve to be updated
   * @param scaledVariableDebt The scaled variable debt
   * @param liquidityIndex The last stored liquidity index
   * @param variableBorrowIndex The last stored variable borrow index
   **/
  function _updateIndexes(
    DataTypes.ReserveData storage reserve,
    uint256 scaledVariableDebt,
    uint256 liquidityIndex,
    uint256 variableBorrowIndex,
    uint40 timestamp
  ) internal returns (uint256, uint256) {
    uint256 currentLiquidityRate = reserve.currentLiquidityRate;

    uint256 newLiquidityIndex = liquidityIndex;
    uint256 newVariableBorrowIndex = variableBorrowIndex;

    //only cumulating if there is any income being produced
    if (currentLiquidityRate > 0) {
      uint256 cumulatedLiquidityInterest =
        MathUtils.calculateLinearInterest(currentLiquidityRate, timestamp);
      newLiquidityIndex = cumulatedLiquidityInterest.rayMul(liquidityIndex);
      require(newLiquidityIndex <= type(uint128).max, Errors.RL_LIQUIDITY_INDEX_OVERFLOW);

      reserve.liquidityIndex = uint128(newLiquidityIndex);

      //as the liquidity rate might come only from stable rate loans, we need to ensure
      //that there is actual variable debt before accumulating
      if (scaledVariableDebt != 0) {
        uint256 cumulatedVariableBorrowInterest =
          MathUtils.calculateCompoundedInterest(reserve.currentVariableBorrowRate, timestamp);
        newVariableBorrowIndex = cumulatedVariableBorrowInterest.rayMul(variableBorrowIndex);
        require(
          newVariableBorrowIndex <= type(uint128).max,
          Errors.RL_VARIABLE_BORROW_INDEX_OVERFLOW
        );
        reserve.variableBorrowIndex = uint128(newVariableBorrowIndex);
      }
    }

    //solium-disable-next-line
    reserve.lastUpdateTimestamp = uint40(block.timestamp);
    return (newLiquidityIndex, newVariableBorrowIndex);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {Errors} from '../helpers/Errors.sol';
import {DataTypes} from '../types/DataTypes.sol';

/**
 * @title ReserveConfiguration library
 * @author Aave
 * @notice Implements the bitmap logic to handle the reserve configuration
 */
library ReserveConfiguration {
  uint256 constant LTV_MASK =                   0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF0000; // prettier-ignore
  uint256 constant LIQUIDATION_THRESHOLD_MASK = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF0000FFFF; // prettier-ignore
  uint256 constant LIQUIDATION_BONUS_MASK =     0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF0000FFFFFFFF; // prettier-ignore
  uint256 constant DECIMALS_MASK =              0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00FFFFFFFFFFFF; // prettier-ignore
  uint256 constant ACTIVE_MASK =                0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFF; // prettier-ignore
  uint256 constant FROZEN_MASK =                0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFDFFFFFFFFFFFFFF; // prettier-ignore
  uint256 constant BORROWING_MASK =             0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFBFFFFFFFFFFFFFF; // prettier-ignore
  uint256 constant STABLE_BORROWING_MASK =      0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF7FFFFFFFFFFFFFF; // prettier-ignore
  uint256 constant RESERVE_FACTOR_MASK =        0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF0000FFFFFFFFFFFFFFFF; // prettier-ignore

  /// @dev For the LTV, the start bit is 0 (up to 15), hence no bitshifting is needed
  uint256 constant LIQUIDATION_THRESHOLD_START_BIT_POSITION = 16;
  uint256 constant LIQUIDATION_BONUS_START_BIT_POSITION = 32;
  uint256 constant RESERVE_DECIMALS_START_BIT_POSITION = 48;
  uint256 constant IS_ACTIVE_START_BIT_POSITION = 56;
  uint256 constant IS_FROZEN_START_BIT_POSITION = 57;
  uint256 constant BORROWING_ENABLED_START_BIT_POSITION = 58;
  uint256 constant STABLE_BORROWING_ENABLED_START_BIT_POSITION = 59;
  uint256 constant RESERVE_FACTOR_START_BIT_POSITION = 64;

  uint256 constant MAX_VALID_LTV = 65535;
  uint256 constant MAX_VALID_LIQUIDATION_THRESHOLD = 65535;
  uint256 constant MAX_VALID_LIQUIDATION_BONUS = 65535;
  uint256 constant MAX_VALID_DECIMALS = 255;
  uint256 constant MAX_VALID_RESERVE_FACTOR = 65535;

  /**
   * @dev Sets the Loan to Value of the reserve
   * @param self The reserve configuration
   * @param ltv the new ltv
   **/
  function setLtv(DataTypes.ReserveConfigurationMap memory self, uint256 ltv) internal pure {
    require(ltv <= MAX_VALID_LTV, Errors.RC_INVALID_LTV);

    self.data = (self.data & LTV_MASK) | ltv;
  }

  /**
   * @dev Gets the Loan to Value of the reserve
   * @param self The reserve configuration
   * @return The loan to value
   **/
  function getLtv(DataTypes.ReserveConfigurationMap storage self) internal view returns (uint256) {
    return self.data & ~LTV_MASK;
  }

  /**
   * @dev Sets the liquidation threshold of the reserve
   * @param self The reserve configuration
   * @param threshold The new liquidation threshold
   **/
  function setLiquidationThreshold(DataTypes.ReserveConfigurationMap memory self, uint256 threshold)
    internal
    pure
  {
    require(threshold <= MAX_VALID_LIQUIDATION_THRESHOLD, Errors.RC_INVALID_LIQ_THRESHOLD);

    self.data =
      (self.data & LIQUIDATION_THRESHOLD_MASK) |
      (threshold << LIQUIDATION_THRESHOLD_START_BIT_POSITION);
  }

  /**
   * @dev Gets the liquidation threshold of the reserve
   * @param self The reserve configuration
   * @return The liquidation threshold
   **/
  function getLiquidationThreshold(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (uint256)
  {
    return (self.data & ~LIQUIDATION_THRESHOLD_MASK) >> LIQUIDATION_THRESHOLD_START_BIT_POSITION;
  }

  /**
   * @dev Sets the liquidation bonus of the reserve
   * @param self The reserve configuration
   * @param bonus The new liquidation bonus
   **/
  function setLiquidationBonus(DataTypes.ReserveConfigurationMap memory self, uint256 bonus)
    internal
    pure
  {
    require(bonus <= MAX_VALID_LIQUIDATION_BONUS, Errors.RC_INVALID_LIQ_BONUS);

    self.data =
      (self.data & LIQUIDATION_BONUS_MASK) |
      (bonus << LIQUIDATION_BONUS_START_BIT_POSITION);
  }

  /**
   * @dev Gets the liquidation bonus of the reserve
   * @param self The reserve configuration
   * @return The liquidation bonus
   **/
  function getLiquidationBonus(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (uint256)
  {
    return (self.data & ~LIQUIDATION_BONUS_MASK) >> LIQUIDATION_BONUS_START_BIT_POSITION;
  }

  /**
   * @dev Sets the decimals of the underlying asset of the reserve
   * @param self The reserve configuration
   * @param decimals The decimals
   **/
  function setDecimals(DataTypes.ReserveConfigurationMap memory self, uint256 decimals)
    internal
    pure
  {
    require(decimals <= MAX_VALID_DECIMALS, Errors.RC_INVALID_DECIMALS);

    self.data = (self.data & DECIMALS_MASK) | (decimals << RESERVE_DECIMALS_START_BIT_POSITION);
  }

  /**
   * @dev Gets the decimals of the underlying asset of the reserve
   * @param self The reserve configuration
   * @return The decimals of the asset
   **/
  function getDecimals(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (uint256)
  {
    return (self.data & ~DECIMALS_MASK) >> RESERVE_DECIMALS_START_BIT_POSITION;
  }

  /**
   * @dev Sets the active state of the reserve
   * @param self The reserve configuration
   * @param active The active state
   **/
  function setActive(DataTypes.ReserveConfigurationMap memory self, bool active) internal pure {
    self.data =
      (self.data & ACTIVE_MASK) |
      (uint256(active ? 1 : 0) << IS_ACTIVE_START_BIT_POSITION);
  }

  /**
   * @dev Gets the active state of the reserve
   * @param self The reserve configuration
   * @return The active state
   **/
  function getActive(DataTypes.ReserveConfigurationMap storage self) internal view returns (bool) {
    return (self.data & ~ACTIVE_MASK) != 0;
  }

  /**
   * @dev Sets the frozen state of the reserve
   * @param self The reserve configuration
   * @param frozen The frozen state
   **/
  function setFrozen(DataTypes.ReserveConfigurationMap memory self, bool frozen) internal pure {
    self.data =
      (self.data & FROZEN_MASK) |
      (uint256(frozen ? 1 : 0) << IS_FROZEN_START_BIT_POSITION);
  }

  /**
   * @dev Gets the frozen state of the reserve
   * @param self The reserve configuration
   * @return The frozen state
   **/
  function getFrozen(DataTypes.ReserveConfigurationMap storage self) internal view returns (bool) {
    return (self.data & ~FROZEN_MASK) != 0;
  }

  /**
   * @dev Enables or disables borrowing on the reserve
   * @param self The reserve configuration
   * @param enabled True if the borrowing needs to be enabled, false otherwise
   **/
  function setBorrowingEnabled(DataTypes.ReserveConfigurationMap memory self, bool enabled)
    internal
    pure
  {
    self.data =
      (self.data & BORROWING_MASK) |
      (uint256(enabled ? 1 : 0) << BORROWING_ENABLED_START_BIT_POSITION);
  }

  /**
   * @dev Gets the borrowing state of the reserve
   * @param self The reserve configuration
   * @return The borrowing state
   **/
  function getBorrowingEnabled(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (bool)
  {
    return (self.data & ~BORROWING_MASK) != 0;
  }

  /**
   * @dev Enables or disables stable rate borrowing on the reserve
   * @param self The reserve configuration
   * @param enabled True if the stable rate borrowing needs to be enabled, false otherwise
   **/
  function setStableRateBorrowingEnabled(
    DataTypes.ReserveConfigurationMap memory self,
    bool enabled
  ) internal pure {
    self.data =
      (self.data & STABLE_BORROWING_MASK) |
      (uint256(enabled ? 1 : 0) << STABLE_BORROWING_ENABLED_START_BIT_POSITION);
  }

  /**
   * @dev Gets the stable rate borrowing state of the reserve
   * @param self The reserve configuration
   * @return The stable rate borrowing state
   **/
  function getStableRateBorrowingEnabled(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (bool)
  {
    return (self.data & ~STABLE_BORROWING_MASK) != 0;
  }

  /**
   * @dev Sets the reserve factor of the reserve
   * @param self The reserve configuration
   * @param reserveFactor The reserve factor
   **/
  function setReserveFactor(DataTypes.ReserveConfigurationMap memory self, uint256 reserveFactor)
    internal
    pure
  {
    require(reserveFactor <= MAX_VALID_RESERVE_FACTOR, Errors.RC_INVALID_RESERVE_FACTOR);

    self.data =
      (self.data & RESERVE_FACTOR_MASK) |
      (reserveFactor << RESERVE_FACTOR_START_BIT_POSITION);
  }

  /**
   * @dev Gets the reserve factor of the reserve
   * @param self The reserve configuration
   * @return The reserve factor
   **/
  function getReserveFactor(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (uint256)
  {
    return (self.data & ~RESERVE_FACTOR_MASK) >> RESERVE_FACTOR_START_BIT_POSITION;
  }

  /**
   * @dev Gets the configuration flags of the reserve
   * @param self The reserve configuration
   * @return The state flags representing active, frozen, borrowing enabled, stableRateBorrowing enabled
   **/
  function getFlags(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (
      bool,
      bool,
      bool,
      bool
    )
  {
    uint256 dataLocal = self.data;

    return (
      (dataLocal & ~ACTIVE_MASK) != 0,
      (dataLocal & ~FROZEN_MASK) != 0,
      (dataLocal & ~BORROWING_MASK) != 0,
      (dataLocal & ~STABLE_BORROWING_MASK) != 0
    );
  }

  /**
   * @dev Gets the configuration paramters of the reserve
   * @param self The reserve configuration
   * @return The state params representing ltv, liquidation threshold, liquidation bonus, the reserve decimals
   **/
  function getParams(DataTypes.ReserveConfigurationMap storage self)
    internal
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      uint256
    )
  {
    uint256 dataLocal = self.data;

    return (
      dataLocal & ~LTV_MASK,
      (dataLocal & ~LIQUIDATION_THRESHOLD_MASK) >> LIQUIDATION_THRESHOLD_START_BIT_POSITION,
      (dataLocal & ~LIQUIDATION_BONUS_MASK) >> LIQUIDATION_BONUS_START_BIT_POSITION,
      (dataLocal & ~DECIMALS_MASK) >> RESERVE_DECIMALS_START_BIT_POSITION,
      (dataLocal & ~RESERVE_FACTOR_MASK) >> RESERVE_FACTOR_START_BIT_POSITION
    );
  }

  /**
   * @dev Gets the configuration paramters of the reserve from a memory object
   * @param self The reserve configuration
   * @return The state params representing ltv, liquidation threshold, liquidation bonus, the reserve decimals
   **/
  function getParamsMemory(DataTypes.ReserveConfigurationMap memory self)
    internal
    pure
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      uint256
    )
  {
    return (
      self.data & ~LTV_MASK,
      (self.data & ~LIQUIDATION_THRESHOLD_MASK) >> LIQUIDATION_THRESHOLD_START_BIT_POSITION,
      (self.data & ~LIQUIDATION_BONUS_MASK) >> LIQUIDATION_BONUS_START_BIT_POSITION,
      (self.data & ~DECIMALS_MASK) >> RESERVE_DECIMALS_START_BIT_POSITION,
      (self.data & ~RESERVE_FACTOR_MASK) >> RESERVE_FACTOR_START_BIT_POSITION
    );
  }

  /**
   * @dev Gets the configuration flags of the reserve from a memory object
   * @param self The reserve configuration
   * @return The state flags representing active, frozen, borrowing enabled, stableRateBorrowing enabled
   **/
  function getFlagsMemory(DataTypes.ReserveConfigurationMap memory self)
    internal
    pure
    returns (
      bool,
      bool,
      bool,
      bool
    )
  {
    return (
      (self.data & ~ACTIVE_MASK) != 0,
      (self.data & ~FROZEN_MASK) != 0,
      (self.data & ~BORROWING_MASK) != 0,
      (self.data & ~STABLE_BORROWING_MASK) != 0
    );
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {Errors} from '../helpers/Errors.sol';
import {DataTypes} from '../types/DataTypes.sol';

/**
 * @title UserConfiguration library
 * @author Aave
 * @notice Implements the bitmap logic to handle the user configuration
 */
library UserConfiguration {
  uint256 internal constant BORROWING_MASK =
    0x5555555555555555555555555555555555555555555555555555555555555555;

  /**
   * @dev Sets if the user is borrowing the reserve identified by reserveIndex
   * @param self The configuration object
   * @param reserveIndex The index of the reserve in the bitmap
   * @param borrowing True if the user is borrowing the reserve, false otherwise
   **/
  function setBorrowing(
    DataTypes.UserConfigurationMap storage self,
    uint256 reserveIndex,
    bool borrowing
  ) internal {
    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
    self.data =
      (self.data & ~(1 << (reserveIndex * 2))) |
      (uint256(borrowing ? 1 : 0) << (reserveIndex * 2));
  }

  /**
   * @dev Sets if the user is using as collateral the reserve identified by reserveIndex
   * @param self The configuration object
   * @param reserveIndex The index of the reserve in the bitmap
   * @param usingAsCollateral True if the user is usin the reserve as collateral, false otherwise
   **/
  function setUsingAsCollateral(
    DataTypes.UserConfigurationMap storage self,
    uint256 reserveIndex,
    bool usingAsCollateral
  ) internal {
    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
    self.data =
      (self.data & ~(1 << (reserveIndex * 2 + 1))) |
      (uint256(usingAsCollateral ? 1 : 0) << (reserveIndex * 2 + 1));
  }

  /**
   * @dev Used to validate if a user has been using the reserve for borrowing or as collateral
   * @param self The configuration object
   * @param reserveIndex The index of the reserve in the bitmap
   * @return True if the user has been using a reserve for borrowing or as collateral, false otherwise
   **/
  function isUsingAsCollateralOrBorrowing(
    DataTypes.UserConfigurationMap memory self,
    uint256 reserveIndex
  ) internal pure returns (bool) {
    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
    return (self.data >> (reserveIndex * 2)) & 3 != 0;
  }

  /**
   * @dev Used to validate if a user has been using the reserve for borrowing
   * @param self The configuration object
   * @param reserveIndex The index of the reserve in the bitmap
   * @return True if the user has been using a reserve for borrowing, false otherwise
   **/
  function isBorrowing(DataTypes.UserConfigurationMap memory self, uint256 reserveIndex)
    internal
    pure
    returns (bool)
  {
    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
    return (self.data >> (reserveIndex * 2)) & 1 != 0;
  }

  /**
   * @dev Used to validate if a user has been using the reserve as collateral
   * @param self The configuration object
   * @param reserveIndex The index of the reserve in the bitmap
   * @return True if the user has been using a reserve as collateral, false otherwise
   **/
  function isUsingAsCollateral(DataTypes.UserConfigurationMap memory self, uint256 reserveIndex)
    internal
    pure
    returns (bool)
  {
    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
    return (self.data >> (reserveIndex * 2 + 1)) & 1 != 0;
  }

  /**
   * @dev Used to validate if a user has been borrowing from any reserve
   * @param self The configuration object
   * @return True if the user has been borrowing any reserve, false otherwise
   **/
  function isBorrowingAny(DataTypes.UserConfigurationMap memory self) internal pure returns (bool) {
    return self.data & BORROWING_MASK != 0;
  }

  /**
   * @dev Used to validate if a user has not been using any reserve
   * @param self The configuration object
   * @return True if the user has been borrowing any reserve, false otherwise
   **/
  function isEmpty(DataTypes.UserConfigurationMap memory self) internal pure returns (bool) {
    return self.data == 0;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title IReserveInterestRateStrategyInterface interface
 * @dev Interface for the calculation of the interest rates
 * @author Aave
 */
interface IReserveInterestRateStrategy {
  function baseVariableBorrowRate() external view returns (uint256);

  function getMaxVariableBorrowRate() external view returns (uint256);

  function calculateInterestRates(
    address reserve,
    uint256 availableLiquidity,
    uint256 totalStableDebt,
    uint256 totalVariableDebt,
    uint256 averageStableBorrowRate,
    uint256 reserveFactor
  )
    external
    view
    returns (
      uint256,
      uint256,
      uint256
    );

  function calculateInterestRates(
    address reserve,
    address aToken,
    uint256 liquidityAdded,
    uint256 liquidityTaken,
    uint256 totalStableDebt,
    uint256 totalVariableDebt,
    uint256 averageStableBorrowRate,
    uint256 reserveFactor
  )
    external
    view
    returns (
      uint256 liquidityRate,
      uint256 stableBorrowRate,
      uint256 variableBorrowRate
    );
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {SafeMath} from '../../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {WadRayMath} from './WadRayMath.sol';

library MathUtils {
  using SafeMath for uint256;
  using WadRayMath for uint256;

  /// @dev Ignoring leap years
  uint256 internal constant SECONDS_PER_YEAR = 365 days;

  /**
   * @dev Function to calculate the interest accumulated using a linear interest rate formula
   * @param rate The interest rate, in ray
   * @param lastUpdateTimestamp The timestamp of the last update of the interest
   * @return The interest rate linearly accumulated during the timeDelta, in ray
   **/

  function calculateLinearInterest(uint256 rate, uint40 lastUpdateTimestamp)
    internal
    view
    returns (uint256)
  {
    //solium-disable-next-line
    uint256 timeDifference = block.timestamp.sub(uint256(lastUpdateTimestamp));

    return (rate.mul(timeDifference) / SECONDS_PER_YEAR).add(WadRayMath.ray());
  }

  /**
   * @dev Function to calculate the interest using a compounded interest rate formula
   * To avoid expensive exponentiation, the calculation is performed using a binomial approximation:
   *
   *  (1+x)^n = 1+n*x+[n/2*(n-1)]*x^2+[n/6*(n-1)*(n-2)*x^3...
   *
   * The approximation slightly underpays liquidity providers and undercharges borrowers, with the advantage of great gas cost reductions
   * The whitepaper contains reference to the approximation and a table showing the margin of error per different time periods
   *
   * @param rate The interest rate, in ray
   * @param lastUpdateTimestamp The timestamp of the last update of the interest
   * @return The interest rate compounded during the timeDelta, in ray
   **/
  function calculateCompoundedInterest(
    uint256 rate,
    uint40 lastUpdateTimestamp,
    uint256 currentTimestamp
  ) internal pure returns (uint256) {
    //solium-disable-next-line
    uint256 exp = currentTimestamp.sub(uint256(lastUpdateTimestamp));

    if (exp == 0) {
      return WadRayMath.ray();
    }

    uint256 expMinusOne = exp - 1;

    uint256 expMinusTwo = exp > 2 ? exp - 2 : 0;

    uint256 ratePerSecond = rate / SECONDS_PER_YEAR;

    uint256 basePowerTwo = ratePerSecond.rayMul(ratePerSecond);
    uint256 basePowerThree = basePowerTwo.rayMul(ratePerSecond);

    uint256 secondTerm = exp.mul(expMinusOne).mul(basePowerTwo) / 2;
    uint256 thirdTerm = exp.mul(expMinusOne).mul(expMinusTwo).mul(basePowerThree) / 6;

    return WadRayMath.ray().add(ratePerSecond.mul(exp)).add(secondTerm).add(thirdTerm);
  }

  /**
   * @dev Calculates the compounded interest between the timestamp of the last update and the current block timestamp
   * @param rate The interest rate (in ray)
   * @param lastUpdateTimestamp The timestamp from which the interest accumulation needs to be calculated
   **/
  function calculateCompoundedInterest(uint256 rate, uint40 lastUpdateTimestamp)
    internal
    view
    returns (uint256)
  {
    return calculateCompoundedInterest(rate, lastUpdateTimestamp, block.timestamp);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {SafeMath} from '../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IERC20} from '../../dependencies/openzeppelin/contracts/IERC20.sol';

import {FlashLoanReceiverBase} from '../../flashloan/base/FlashLoanReceiverBase.sol';
import {MintableERC20} from '../tokens/MintableERC20.sol';
import {SafeERC20} from '../../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {ILendingPoolAddressesProvider} from '../../interfaces/ILendingPoolAddressesProvider.sol';

contract MockFlashLoanReceiver is FlashLoanReceiverBase {
  using SafeERC20 for IERC20;

  ILendingPoolAddressesProvider internal _provider;

  event ExecutedWithFail(address[] _assets, uint256[] _amounts, uint256[] _premiums);
  event ExecutedWithSuccess(address[] _assets, uint256[] _amounts, uint256[] _premiums);

  bool _failExecution;
  uint256 _amountToApprove;
  bool _simulateEOA;

  constructor(ILendingPoolAddressesProvider provider) public FlashLoanReceiverBase(provider) {}

  function setFailExecutionTransfer(bool fail) public {
    _failExecution = fail;
  }

  function setAmountToApprove(uint256 amountToApprove) public {
    _amountToApprove = amountToApprove;
  }

  function setSimulateEOA(bool flag) public {
    _simulateEOA = flag;
  }

  function amountToApprove() public view returns (uint256) {
    return _amountToApprove;
  }

  function simulateEOA() public view returns (bool) {
    return _simulateEOA;
  }

  function executeOperation(
    address[] memory assets,
    uint256[] memory amounts,
    uint256[] memory premiums,
    address initiator,
    bytes memory params
  ) public override returns (bool) {
    params;
    initiator;

    if (_failExecution) {
      emit ExecutedWithFail(assets, amounts, premiums);
      return !_simulateEOA;
    }

    for (uint256 i = 0; i < assets.length; i++) {
      //mint to this contract the specific amount
      MintableERC20 token = MintableERC20(assets[i]);

      //check the contract has the specified balance
      require(
        amounts[i] <= IERC20(assets[i]).balanceOf(address(this)),
        'Invalid balance for the contract'
      );

      uint256 amountToReturn =
        (_amountToApprove != 0) ? _amountToApprove : amounts[i].add(premiums[i]);
      //execution does not fail - mint tokens and return them to the _destination

      token.mint(premiums[i]);

      IERC20(assets[i]).approve(address(LENDING_POOL), amountToReturn);
    }

    emit ExecutedWithSuccess(assets, amounts, premiums);

    return true;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {ERC20} from '../../dependencies/openzeppelin/contracts/ERC20.sol';

/**
 * @title ERC20Mintable
 * @dev ERC20 minting logic
 */
contract MintableERC20 is ERC20 {
  constructor(
    string memory name,
    string memory symbol,
    uint8 decimals
  ) public ERC20(name, symbol) {
    _setupDecimals(decimals);
  }

  /**
   * @dev Function to mint tokens
   * @param value The amount of tokens to mint.
   * @return A boolean that indicates if the operation was successful.
   */
  function mint(uint256 value) public returns (bool) {
    _mint(_msgSender(), value);
    return true;
  }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

import './Context.sol';
import './IERC20.sol';
import './SafeMath.sol';
import './Address.sol';

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
  using SafeMath for uint256;
  using Address for address;

  mapping(address => uint256) private _balances;

  mapping(address => mapping(address => uint256)) private _allowances;

  uint256 private _totalSupply;

  string private _name;
  string private _symbol;
  uint8 private _decimals;

  /**
   * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
   * a default value of 18.
   *
   * To select a different value for {decimals}, use {_setupDecimals}.
   *
   * All three of these values are immutable: they can only be set once during
   * construction.
   */
  constructor(string memory name, string memory symbol) public {
    _name = name;
    _symbol = symbol;
    _decimals = 18;
  }

  /**
   * @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. This is the value {ERC20} uses, unless {_setupDecimals} is
   * called.
   *
   * 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;
  }

  /**
   * @dev See {IERC20-totalSupply}.
   */
  function totalSupply() public view override returns (uint256) {
    return _totalSupply;
  }

  /**
   * @dev See {IERC20-balanceOf}.
   */
  function balanceOf(address account) public view override returns (uint256) {
    return _balances[account];
  }

  /**
   * @dev See {IERC20-transfer}.
   *
   * Requirements:
   *
   * - `recipient` cannot be the zero address.
   * - the caller must have a balance of at least `amount`.
   */
  function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
    _transfer(_msgSender(), recipient, amount);
    return true;
  }

  /**
   * @dev See {IERC20-allowance}.
   */
  function allowance(address owner, address spender)
    public
    view
    virtual
    override
    returns (uint256)
  {
    return _allowances[owner][spender];
  }

  /**
   * @dev See {IERC20-approve}.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   */
  function approve(address spender, uint256 amount) public virtual override returns (bool) {
    _approve(_msgSender(), spender, amount);
    return true;
  }

  /**
   * @dev See {IERC20-transferFrom}.
   *
   * Emits an {Approval} event indicating the updated allowance. This is not
   * required by the EIP. See the note at the beginning of {ERC20};
   *
   * Requirements:
   * - `sender` and `recipient` cannot be the zero address.
   * - `sender` must have a balance of at least `amount`.
   * - the caller must have allowance for ``sender``'s tokens of at least
   * `amount`.
   */
  function transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) public virtual override returns (bool) {
    _transfer(sender, recipient, amount);
    _approve(
      sender,
      _msgSender(),
      _allowances[sender][_msgSender()].sub(amount, 'ERC20: transfer amount exceeds allowance')
    );
    return true;
  }

  /**
   * @dev Atomically increases the allowance granted to `spender` by the caller.
   *
   * This is an alternative to {approve} that can be used as a mitigation for
   * problems described in {IERC20-approve}.
   *
   * Emits an {Approval} event indicating the updated allowance.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   */
  function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
    _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
    return true;
  }

  /**
   * @dev Atomically decreases the allowance granted to `spender` by the caller.
   *
   * This is an alternative to {approve} that can be used as a mitigation for
   * problems described in {IERC20-approve}.
   *
   * Emits an {Approval} event indicating the updated allowance.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   * - `spender` must have allowance for the caller of at least
   * `subtractedValue`.
   */
  function decreaseAllowance(address spender, uint256 subtractedValue)
    public
    virtual
    returns (bool)
  {
    _approve(
      _msgSender(),
      spender,
      _allowances[_msgSender()][spender].sub(
        subtractedValue,
        'ERC20: decreased allowance below zero'
      )
    );
    return true;
  }

  /**
   * @dev Moves tokens `amount` from `sender` to `recipient`.
   *
   * This is internal function is equivalent to {transfer}, and can be used to
   * e.g. implement automatic token fees, slashing mechanisms, etc.
   *
   * Emits a {Transfer} event.
   *
   * Requirements:
   *
   * - `sender` cannot be the zero address.
   * - `recipient` cannot be the zero address.
   * - `sender` must have a balance of at least `amount`.
   */
  function _transfer(
    address sender,
    address recipient,
    uint256 amount
  ) internal virtual {
    require(sender != address(0), 'ERC20: transfer from the zero address');
    require(recipient != address(0), 'ERC20: transfer to the zero address');

    _beforeTokenTransfer(sender, recipient, amount);

    _balances[sender] = _balances[sender].sub(amount, 'ERC20: transfer amount exceeds balance');
    _balances[recipient] = _balances[recipient].add(amount);
    emit Transfer(sender, recipient, amount);
  }

  /** @dev Creates `amount` tokens and assigns them to `account`, increasing
   * the total supply.
   *
   * Emits a {Transfer} event with `from` set to the zero address.
   *
   * Requirements
   *
   * - `to` cannot be the zero address.
   */
  function _mint(address account, uint256 amount) internal virtual {
    require(account != address(0), 'ERC20: mint to the zero address');

    _beforeTokenTransfer(address(0), account, amount);

    _totalSupply = _totalSupply.add(amount);
    _balances[account] = _balances[account].add(amount);
    emit Transfer(address(0), account, amount);
  }

  /**
   * @dev Destroys `amount` tokens from `account`, reducing the
   * total supply.
   *
   * Emits a {Transfer} event with `to` set to the zero address.
   *
   * Requirements
   *
   * - `account` cannot be the zero address.
   * - `account` must have at least `amount` tokens.
   */
  function _burn(address account, uint256 amount) internal virtual {
    require(account != address(0), 'ERC20: burn from the zero address');

    _beforeTokenTransfer(account, address(0), amount);

    _balances[account] = _balances[account].sub(amount, 'ERC20: burn amount exceeds balance');
    _totalSupply = _totalSupply.sub(amount);
    emit Transfer(account, address(0), amount);
  }

  /**
   * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
   *
   * This is internal function is equivalent to `approve`, and can be used to
   * e.g. set automatic allowances for certain subsystems, etc.
   *
   * Emits an {Approval} event.
   *
   * Requirements:
   *
   * - `owner` cannot be the zero address.
   * - `spender` cannot be the zero address.
   */
  function _approve(
    address owner,
    address spender,
    uint256 amount
  ) internal virtual {
    require(owner != address(0), 'ERC20: approve from the zero address');
    require(spender != address(0), 'ERC20: approve to the zero address');

    _allowances[owner][spender] = amount;
    emit Approval(owner, spender, amount);
  }

  /**
   * @dev Sets {decimals} to a value other than the default one of 18.
   *
   * WARNING: This function should only be called from the constructor. Most
   * applications that interact with token contracts will not expect
   * {decimals} to ever change, and may work incorrectly if it does.
   */
  function _setupDecimals(uint8 decimals_) internal {
    _decimals = decimals_;
  }

  /**
   * @dev Hook that is called before any transfer of tokens. This includes
   * minting and burning.
   *
   * Calling conditions:
   *
   * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
   * will be to transferred to `to`.
   * - when `from` is zero, `amount` tokens will be minted for `to`.
   * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
   * - `from` and `to` are never both zero.
   *
   * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
   */
  function _beforeTokenTransfer(
    address from,
    address to,
    uint256 amount
  ) internal virtual {}
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

pragma experimental ABIEncoderV2;

import {Address} from '../dependencies/openzeppelin/contracts/Address.sol';
import {IERC20} from '../dependencies/openzeppelin/contracts/IERC20.sol';

import {ILendingPoolAddressesProvider} from '../interfaces/ILendingPoolAddressesProvider.sol';
import {ILendingPool} from '../interfaces/ILendingPool.sol';
import {SafeERC20} from '../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {ReserveConfiguration} from '../protocol/libraries/configuration/ReserveConfiguration.sol';
import {DataTypes} from '../protocol/libraries/types/DataTypes.sol';

/**
 * @title WalletBalanceProvider contract
 * @author Aave, influenced by https://github.com/wbobeirne/eth-balance-checker/blob/master/contracts/BalanceChecker.sol
 * @notice Implements a logic of getting multiple tokens balance for one user address
 * @dev NOTE: THIS CONTRACT IS NOT USED WITHIN THE AAVE PROTOCOL. It's an accessory contract used to reduce the number of calls
 * towards the blockchain from the Aave backend.
 **/
contract WalletBalanceProvider {
  using Address for address payable;
  using Address for address;
  using SafeERC20 for IERC20;
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;

  address constant MOCK_ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;

  /**
    @dev Fallback function, don't accept any ETH
    **/
  receive() external payable {
    //only contracts can send ETH to the core
    require(msg.sender.isContract(), '22');
  }

  /**
    @dev Check the token balance of a wallet in a token contract

    Returns the balance of the token for user. Avoids possible errors:
      - return 0 on non-contract address
    **/
  function balanceOf(address user, address token) public view returns (uint256) {
    if (token == MOCK_ETH_ADDRESS) {
      return user.balance; // ETH balance
      // check if token is actually a contract
    } else if (token.isContract()) {
      return IERC20(token).balanceOf(user);
    }
    revert('INVALID_TOKEN');
  }

  /**
   * @notice Fetches, for a list of _users and _tokens (ETH included with mock address), the balances
   * @param users The list of users
   * @param tokens The list of tokens
   * @return And array with the concatenation of, for each user, his/her balances
   **/
  function batchBalanceOf(address[] calldata users, address[] calldata tokens)
    external
    view
    returns (uint256[] memory)
  {
    uint256[] memory balances = new uint256[](users.length * tokens.length);

    for (uint256 i = 0; i < users.length; i++) {
      for (uint256 j = 0; j < tokens.length; j++) {
        balances[i * tokens.length + j] = balanceOf(users[i], tokens[j]);
      }
    }

    return balances;
  }

  /**
    @dev provides balances of user wallet for all reserves available on the pool
    */
  function getUserWalletBalances(address provider, address user)
    external
    view
    returns (address[] memory, uint256[] memory)
  {
    ILendingPool pool = ILendingPool(ILendingPoolAddressesProvider(provider).getLendingPool());

    address[] memory reserves = pool.getReservesList();
    address[] memory reservesWithEth = new address[](reserves.length + 1);
    for (uint256 i = 0; i < reserves.length; i++) {
      reservesWithEth[i] = reserves[i];
    }
    reservesWithEth[reserves.length] = MOCK_ETH_ADDRESS;

    uint256[] memory balances = new uint256[](reservesWithEth.length);

    for (uint256 j = 0; j < reserves.length; j++) {
      DataTypes.ReserveConfigurationMap memory configuration =
        pool.getConfiguration(reservesWithEth[j]);

      (bool isActive, , , ) = configuration.getFlagsMemory();

      if (!isActive) {
        balances[j] = 0;
        continue;
      }
      balances[j] = balanceOf(user, reservesWithEth[j]);
    }
    balances[reserves.length] = balanceOf(user, MOCK_ETH_ADDRESS);

    return (reservesWithEth, balances);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {Ownable} from '../dependencies/openzeppelin/contracts/Ownable.sol';
import {IERC20} from '../dependencies/openzeppelin/contracts/IERC20.sol';
import {IWETH} from './interfaces/IWETH.sol';
import {IWETHGateway} from './interfaces/IWETHGateway.sol';
import {ILendingPool} from '../interfaces/ILendingPool.sol';
import {IAToken} from '../interfaces/IAToken.sol';
import {ReserveConfiguration} from '../protocol/libraries/configuration/ReserveConfiguration.sol';
import {UserConfiguration} from '../protocol/libraries/configuration/UserConfiguration.sol';
import {Helpers} from '../protocol/libraries/helpers/Helpers.sol';
import {DataTypes} from '../protocol/libraries/types/DataTypes.sol';

contract WETHGateway is IWETHGateway, Ownable {
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;
  using UserConfiguration for DataTypes.UserConfigurationMap;

  IWETH internal immutable WETH;

  /**
   * @dev Sets the WETH address and the LendingPoolAddressesProvider address. Infinite approves lending pool.
   * @param weth Address of the Wrapped Ether contract
   **/
  constructor(address weth) public {
    WETH = IWETH(weth);
  }

  function authorizeLendingPool(address lendingPool) external onlyOwner {
    WETH.approve(lendingPool, uint256(-1));
  }

  /**
   * @dev deposits WETH into the reserve, using native ETH. A corresponding amount of the overlying asset (aTokens)
   * is minted.
   * @param lendingPool address of the targeted underlying lending pool
   * @param onBehalfOf address of the user who will receive the aTokens representing the deposit
   * @param referralCode integrators are assigned a referral code and can potentially receive rewards.
   **/
  function depositETH(
    address lendingPool,
    address onBehalfOf,
    uint16 referralCode
  ) external payable override {
    WETH.deposit{value: msg.value}();
    ILendingPool(lendingPool).deposit(address(WETH), msg.value, onBehalfOf, referralCode);
  }

  /**
   * @dev withdraws the WETH _reserves of msg.sender.
   * @param lendingPool address of the targeted underlying lending pool
   * @param amount amount of aWETH to withdraw and receive native ETH
   * @param to address of the user who will receive native ETH
   */
  function withdrawETH(
    address lendingPool,
    uint256 amount,
    address to
  ) external override {
    IAToken aWETH = IAToken(ILendingPool(lendingPool).getReserveData(address(WETH)).aTokenAddress);
    uint256 userBalance = aWETH.balanceOf(msg.sender);
    uint256 amountToWithdraw = amount;

    // if amount is equal to uint(-1), the user wants to redeem everything
    if (amount == type(uint256).max) {
      amountToWithdraw = userBalance;
    }
    aWETH.transferFrom(msg.sender, address(this), amountToWithdraw);
    ILendingPool(lendingPool).withdraw(address(WETH), amountToWithdraw, address(this));
    WETH.withdraw(amountToWithdraw);
    _safeTransferETH(to, amountToWithdraw);
  }

  /**
   * @dev repays a borrow on the WETH reserve, for the specified amount (or for the whole amount, if uint256(-1) is specified).
   * @param lendingPool address of the targeted underlying lending pool
   * @param amount the amount to repay, or uint256(-1) if the user wants to repay everything
   * @param rateMode the rate mode to repay
   * @param onBehalfOf the address for which msg.sender is repaying
   */
  function repayETH(
    address lendingPool,
    uint256 amount,
    uint256 rateMode,
    address onBehalfOf
  ) external payable override {
    (uint256 stableDebt, uint256 variableDebt) =
      Helpers.getUserCurrentDebtMemory(
        onBehalfOf,
        ILendingPool(lendingPool).getReserveData(address(WETH))
      );

    uint256 paybackAmount =
      DataTypes.InterestRateMode(rateMode) == DataTypes.InterestRateMode.STABLE
        ? stableDebt
        : variableDebt;

    if (amount < paybackAmount) {
      paybackAmount = amount;
    }
    require(msg.value >= paybackAmount, 'msg.value is less than repayment amount');
    WETH.deposit{value: paybackAmount}();
    ILendingPool(lendingPool).repay(address(WETH), msg.value, rateMode, onBehalfOf);

    // refund remaining dust eth
    if (msg.value > paybackAmount) _safeTransferETH(msg.sender, msg.value - paybackAmount);
  }

  /**
   * @dev borrow WETH, unwraps to ETH and send both the ETH and DebtTokens to msg.sender, via `approveDelegation` and onBehalf argument in `LendingPool.borrow`.
   * @param lendingPool address of the targeted underlying lending pool
   * @param amount the amount of ETH to borrow
   * @param interesRateMode the interest rate mode
   * @param referralCode integrators are assigned a referral code and can potentially receive rewards
   */
  function borrowETH(
    address lendingPool,
    uint256 amount,
    uint256 interesRateMode,
    uint16 referralCode
  ) external override {
    ILendingPool(lendingPool).borrow(
      address(WETH),
      amount,
      interesRateMode,
      referralCode,
      msg.sender
    );
    WETH.withdraw(amount);
    _safeTransferETH(msg.sender, amount);
  }

  /**
   * @dev transfer ETH to an address, revert if it fails.
   * @param to recipient of the transfer
   * @param value the amount to send
   */
  function _safeTransferETH(address to, uint256 value) internal {
    (bool success, ) = to.call{value: value}(new bytes(0));
    require(success, 'ETH_TRANSFER_FAILED');
  }

  /**
   * @dev transfer ERC20 from the utility contract, for ERC20 recovery in case of stuck tokens due
   * direct transfers to the contract address.
   * @param token token to transfer
   * @param to recipient of the transfer
   * @param amount amount to send
   */
  function emergencyTokenTransfer(
    address token,
    address to,
    uint256 amount
  ) external onlyOwner {
    IERC20(token).transfer(to, amount);
  }

  /**
   * @dev transfer native Ether from the utility contract, for native Ether recovery in case of stuck Ether
   * due selfdestructs or transfer ether to pre-computated contract address before deployment.
   * @param to recipient of the transfer
   * @param amount amount to send
   */
  function emergencyEtherTransfer(address to, uint256 amount) external onlyOwner {
    _safeTransferETH(to, amount);
  }

  /**
   * @dev Get WETH address used by WETHGateway
   */
  function getWETHAddress() external view returns (address) {
    return address(WETH);
  }

  /**
   * @dev Only WETH contract is allowed to transfer ETH here. Prevent other addresses to send Ether to this contract.
   */
  receive() external payable {
    require(msg.sender == address(WETH), 'Receive not allowed');
  }

  /**
   * @dev Revert fallback calls
   */
  fallback() external payable {
    revert('Fallback not allowed');
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

interface IWETH {
  function deposit() external payable;

  function withdraw(uint256) external;

  function approve(address guy, uint256 wad) external returns (bool);

  function transferFrom(
    address src,
    address dst,
    uint256 wad
  ) external returns (bool);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

interface IWETHGateway {
  function depositETH(
    address lendingPool,
    address onBehalfOf,
    uint16 referralCode
  ) external payable;

  function withdrawETH(
    address lendingPool,
    uint256 amount,
    address onBehalfOf
  ) external;

  function repayETH(
    address lendingPool,
    uint256 amount,
    uint256 rateMode,
    address onBehalfOf
  ) external payable;

  function borrowETH(
    address lendingPool,
    uint256 amount,
    uint256 interesRateMode,
    uint16 referralCode
  ) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {SafeMath} from '../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IReserveInterestRateStrategy} from '../../interfaces/IReserveInterestRateStrategy.sol';
import {WadRayMath} from '../libraries/math/WadRayMath.sol';
import {PercentageMath} from '../libraries/math/PercentageMath.sol';
import {ILendingPoolAddressesProvider} from '../../interfaces/ILendingPoolAddressesProvider.sol';
import {ILendingRateOracle} from '../../interfaces/ILendingRateOracle.sol';
import {IERC20} from '../../dependencies/openzeppelin/contracts/IERC20.sol';

/**
 * @title DefaultReserveInterestRateStrategy contract
 * @notice Implements the calculation of the interest rates depending on the reserve state
 * @dev The model of interest rate is based on 2 slopes, one before the `OPTIMAL_UTILIZATION_RATE`
 * point of utilization and another from that one to 100%
 * - An instance of this same contract, can't be used across different Aave markets, due to the caching
 *   of the LendingPoolAddressesProvider
 * @author Aave
 **/
contract DefaultReserveInterestRateStrategy is IReserveInterestRateStrategy {
  using WadRayMath for uint256;
  using SafeMath for uint256;
  using PercentageMath for uint256;

  /**
   * @dev this constant represents the utilization rate at which the pool aims to obtain most competitive borrow rates.
   * Expressed in ray
   **/
  uint256 public immutable OPTIMAL_UTILIZATION_RATE;

  /**
   * @dev This constant represents the excess utilization rate above the optimal. It's always equal to
   * 1-optimal utilization rate. Added as a constant here for gas optimizations.
   * Expressed in ray
   **/

  uint256 public immutable EXCESS_UTILIZATION_RATE;

  ILendingPoolAddressesProvider public immutable addressesProvider;

  // Base variable borrow rate when Utilization rate = 0. Expressed in ray
  uint256 internal immutable _baseVariableBorrowRate;

  // Slope of the variable interest curve when utilization rate > 0 and <= OPTIMAL_UTILIZATION_RATE. Expressed in ray
  uint256 internal immutable _variableRateSlope1;

  // Slope of the variable interest curve when utilization rate > OPTIMAL_UTILIZATION_RATE. Expressed in ray
  uint256 internal immutable _variableRateSlope2;

  // Slope of the stable interest curve when utilization rate > 0 and <= OPTIMAL_UTILIZATION_RATE. Expressed in ray
  uint256 internal immutable _stableRateSlope1;

  // Slope of the stable interest curve when utilization rate > OPTIMAL_UTILIZATION_RATE. Expressed in ray
  uint256 internal immutable _stableRateSlope2;

  constructor(
    ILendingPoolAddressesProvider provider,
    uint256 optimalUtilizationRate,
    uint256 baseVariableBorrowRate,
    uint256 variableRateSlope1,
    uint256 variableRateSlope2,
    uint256 stableRateSlope1,
    uint256 stableRateSlope2
  ) public {
    OPTIMAL_UTILIZATION_RATE = optimalUtilizationRate;
    EXCESS_UTILIZATION_RATE = WadRayMath.ray().sub(optimalUtilizationRate);
    addressesProvider = provider;
    _baseVariableBorrowRate = baseVariableBorrowRate;
    _variableRateSlope1 = variableRateSlope1;
    _variableRateSlope2 = variableRateSlope2;
    _stableRateSlope1 = stableRateSlope1;
    _stableRateSlope2 = stableRateSlope2;
  }

  function variableRateSlope1() external view returns (uint256) {
    return _variableRateSlope1;
  }

  function variableRateSlope2() external view returns (uint256) {
    return _variableRateSlope2;
  }

  function stableRateSlope1() external view returns (uint256) {
    return _stableRateSlope1;
  }

  function stableRateSlope2() external view returns (uint256) {
    return _stableRateSlope2;
  }

  function baseVariableBorrowRate() external view override returns (uint256) {
    return _baseVariableBorrowRate;
  }

  function getMaxVariableBorrowRate() external view override returns (uint256) {
    return _baseVariableBorrowRate.add(_variableRateSlope1).add(_variableRateSlope2);
  }

  /**
   * @dev Calculates the interest rates depending on the reserve's state and configurations
   * @param reserve The address of the reserve
   * @param liquidityAdded The liquidity added during the operation
   * @param liquidityTaken The liquidity taken during the operation
   * @param totalStableDebt The total borrowed from the reserve a stable rate
   * @param totalVariableDebt The total borrowed from the reserve at a variable rate
   * @param averageStableBorrowRate The weighted average of all the stable rate loans
   * @param reserveFactor The reserve portion of the interest that goes to the treasury of the market
   * @return The liquidity rate, the stable borrow rate and the variable borrow rate
   **/
  function calculateInterestRates(
    address reserve,
    address aToken,
    uint256 liquidityAdded,
    uint256 liquidityTaken,
    uint256 totalStableDebt,
    uint256 totalVariableDebt,
    uint256 averageStableBorrowRate,
    uint256 reserveFactor
  )
    external
    view
    override
    returns (
      uint256,
      uint256,
      uint256
    )
  {
    uint256 availableLiquidity = IERC20(reserve).balanceOf(aToken);
    //avoid stack too deep
    availableLiquidity = availableLiquidity.add(liquidityAdded).sub(liquidityTaken);

    return
      calculateInterestRates(
        reserve,
        availableLiquidity,
        totalStableDebt,
        totalVariableDebt,
        averageStableBorrowRate,
        reserveFactor
      );
  }

  struct CalcInterestRatesLocalVars {
    uint256 totalDebt;
    uint256 currentVariableBorrowRate;
    uint256 currentStableBorrowRate;
    uint256 currentLiquidityRate;
    uint256 utilizationRate;
  }

  /**
   * @dev Calculates the interest rates depending on the reserve's state and configurations.
   * NOTE This function is kept for compatibility with the previous DefaultInterestRateStrategy interface.
   * New protocol implementation uses the new calculateInterestRates() interface
   * @param reserve The address of the reserve
   * @param availableLiquidity The liquidity available in the corresponding aToken
   * @param totalStableDebt The total borrowed from the reserve a stable rate
   * @param totalVariableDebt The total borrowed from the reserve at a variable rate
   * @param averageStableBorrowRate The weighted average of all the stable rate loans
   * @param reserveFactor The reserve portion of the interest that goes to the treasury of the market
   * @return The liquidity rate, the stable borrow rate and the variable borrow rate
   **/
  function calculateInterestRates(
    address reserve,
    uint256 availableLiquidity,
    uint256 totalStableDebt,
    uint256 totalVariableDebt,
    uint256 averageStableBorrowRate,
    uint256 reserveFactor
  )
    public
    view
    override
    returns (
      uint256,
      uint256,
      uint256
    )
  {
    CalcInterestRatesLocalVars memory vars;

    vars.totalDebt = totalStableDebt.add(totalVariableDebt);
    vars.currentVariableBorrowRate = 0;
    vars.currentStableBorrowRate = 0;
    vars.currentLiquidityRate = 0;

    vars.utilizationRate = vars.totalDebt == 0
      ? 0
      : vars.totalDebt.rayDiv(availableLiquidity.add(vars.totalDebt));

    vars.currentStableBorrowRate = ILendingRateOracle(addressesProvider.getLendingRateOracle())
      .getMarketBorrowRate(reserve);

    if (vars.utilizationRate > OPTIMAL_UTILIZATION_RATE) {
      uint256 excessUtilizationRateRatio =
        vars.utilizationRate.sub(OPTIMAL_UTILIZATION_RATE).rayDiv(EXCESS_UTILIZATION_RATE);

      vars.currentStableBorrowRate = vars.currentStableBorrowRate.add(_stableRateSlope1).add(
        _stableRateSlope2.rayMul(excessUtilizationRateRatio)
      );

      vars.currentVariableBorrowRate = _baseVariableBorrowRate.add(_variableRateSlope1).add(
        _variableRateSlope2.rayMul(excessUtilizationRateRatio)
      );
    } else {
      vars.currentStableBorrowRate = vars.currentStableBorrowRate.add(
        _stableRateSlope1.rayMul(vars.utilizationRate.rayDiv(OPTIMAL_UTILIZATION_RATE))
      );
      vars.currentVariableBorrowRate = _baseVariableBorrowRate.add(
        vars.utilizationRate.rayMul(_variableRateSlope1).rayDiv(OPTIMAL_UTILIZATION_RATE)
      );
    }

    vars.currentLiquidityRate = _getOverallBorrowRate(
      totalStableDebt,
      totalVariableDebt,
      vars
        .currentVariableBorrowRate,
      averageStableBorrowRate
    )
      .rayMul(vars.utilizationRate)
      .percentMul(PercentageMath.PERCENTAGE_FACTOR.sub(reserveFactor));

    return (
      vars.currentLiquidityRate,
      vars.currentStableBorrowRate,
      vars.currentVariableBorrowRate
    );
  }

  /**
   * @dev Calculates the overall borrow rate as the weighted average between the total variable debt and total stable debt
   * @param totalStableDebt The total borrowed from the reserve a stable rate
   * @param totalVariableDebt The total borrowed from the reserve at a variable rate
   * @param currentVariableBorrowRate The current variable borrow rate of the reserve
   * @param currentAverageStableBorrowRate The current weighted average of all the stable rate loans
   * @return The weighted averaged borrow rate
   **/
  function _getOverallBorrowRate(
    uint256 totalStableDebt,
    uint256 totalVariableDebt,
    uint256 currentVariableBorrowRate,
    uint256 currentAverageStableBorrowRate
  ) internal pure returns (uint256) {
    uint256 totalDebt = totalStableDebt.add(totalVariableDebt);

    if (totalDebt == 0) return 0;

    uint256 weightedVariableRate = totalVariableDebt.wadToRay().rayMul(currentVariableBorrowRate);

    uint256 weightedStableRate = totalStableDebt.wadToRay().rayMul(currentAverageStableBorrowRate);

    uint256 overallBorrowRate =
      weightedVariableRate.add(weightedStableRate).rayDiv(totalDebt.wadToRay());

    return overallBorrowRate;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title ILendingRateOracle interface
 * @notice Interface for the Aave borrow rate oracle. Provides the average market borrow rate to be used as a base for the stable borrow rate calculations
 **/

interface ILendingRateOracle {
  /**
    @dev returns the market borrow rate in ray
    **/
  function getMarketBorrowRate(address asset) external view returns (uint256);

  /**
    @dev sets the market borrow rate. Rate value must be in ray
    **/
  function setMarketBorrowRate(address asset, uint256 rate) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {IERC20Detailed} from '../dependencies/openzeppelin/contracts/IERC20Detailed.sol';
import {ILendingPoolAddressesProvider} from '../interfaces/ILendingPoolAddressesProvider.sol';
import {IAaveIncentivesController} from '../interfaces/IAaveIncentivesController.sol';
import {IUiPoolDataProvider} from './interfaces/IUiPoolDataProvider.sol';
import {ILendingPool} from '../interfaces/ILendingPool.sol';
import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
import {IAToken} from '../interfaces/IAToken.sol';
import {IVariableDebtToken} from '../interfaces/IVariableDebtToken.sol';
import {IStableDebtToken} from '../interfaces/IStableDebtToken.sol';
import {WadRayMath} from '../protocol/libraries/math/WadRayMath.sol';
import {ReserveConfiguration} from '../protocol/libraries/configuration/ReserveConfiguration.sol';
import {UserConfiguration} from '../protocol/libraries/configuration/UserConfiguration.sol';
import {DataTypes} from '../protocol/libraries/types/DataTypes.sol';
import {
  DefaultReserveInterestRateStrategy
} from '../protocol/lendingpool/DefaultReserveInterestRateStrategy.sol';

contract UiPoolDataProvider is IUiPoolDataProvider {
  using WadRayMath for uint256;
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;
  using UserConfiguration for DataTypes.UserConfigurationMap;

  address public constant MOCK_USD_ADDRESS = 0x10F7Fc1F91Ba351f9C629c5947AD69bD03C05b96;
  IAaveIncentivesController public immutable incentivesController;
  IPriceOracleGetter public immutable oracle;

  constructor(IAaveIncentivesController _incentivesController, IPriceOracleGetter _oracle) public {
    incentivesController = _incentivesController;
    oracle = _oracle;
  }

  function getInterestRateStrategySlopes(DefaultReserveInterestRateStrategy interestRateStrategy)
    internal
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint256
    )
  {
    return (
      interestRateStrategy.variableRateSlope1(),
      interestRateStrategy.variableRateSlope2(),
      interestRateStrategy.stableRateSlope1(),
      interestRateStrategy.stableRateSlope2()
    );
  }

  function getReservesData(ILendingPoolAddressesProvider provider, address user)
    external
    view
    override
    returns (
      AggregatedReserveData[] memory,
      UserReserveData[] memory,
      uint256,
      uint256
    )
  {
    ILendingPool lendingPool = ILendingPool(provider.getLendingPool());
    address[] memory reserves = lendingPool.getReservesList();
    DataTypes.UserConfigurationMap memory userConfig = lendingPool.getUserConfiguration(user);

    AggregatedReserveData[] memory reservesData = new AggregatedReserveData[](reserves.length);
    UserReserveData[] memory userReservesData =
      new UserReserveData[](user != address(0) ? reserves.length : 0);

    for (uint256 i = 0; i < reserves.length; i++) {
      AggregatedReserveData memory reserveData = reservesData[i];
      reserveData.underlyingAsset = reserves[i];

      // reserve current state
      DataTypes.ReserveData memory baseData =
        lendingPool.getReserveData(reserveData.underlyingAsset);
      reserveData.liquidityIndex = baseData.liquidityIndex;
      reserveData.variableBorrowIndex = baseData.variableBorrowIndex;
      reserveData.liquidityRate = baseData.currentLiquidityRate;
      reserveData.variableBorrowRate = baseData.currentVariableBorrowRate;
      reserveData.stableBorrowRate = baseData.currentStableBorrowRate;
      reserveData.lastUpdateTimestamp = baseData.lastUpdateTimestamp;
      reserveData.aTokenAddress = baseData.aTokenAddress;
      reserveData.stableDebtTokenAddress = baseData.stableDebtTokenAddress;
      reserveData.variableDebtTokenAddress = baseData.variableDebtTokenAddress;
      reserveData.interestRateStrategyAddress = baseData.interestRateStrategyAddress;
      reserveData.priceInEth = oracle.getAssetPrice(reserveData.underlyingAsset);

      reserveData.availableLiquidity = IERC20Detailed(reserveData.underlyingAsset).balanceOf(
        reserveData.aTokenAddress
      );
      (
        reserveData.totalPrincipalStableDebt,
        ,
        reserveData.averageStableRate,
        reserveData.stableDebtLastUpdateTimestamp
      ) = IStableDebtToken(reserveData.stableDebtTokenAddress).getSupplyData();
      reserveData.totalScaledVariableDebt = IVariableDebtToken(reserveData.variableDebtTokenAddress)
        .scaledTotalSupply();

      // reserve configuration

      // we're getting this info from the aToken, because some of assets can be not compliant with ETC20Detailed
      reserveData.symbol = IERC20Detailed(reserveData.aTokenAddress).symbol();
      reserveData.name = '';

      (
        reserveData.baseLTVasCollateral,
        reserveData.reserveLiquidationThreshold,
        reserveData.reserveLiquidationBonus,
        reserveData.decimals,
        reserveData.reserveFactor
      ) = baseData.configuration.getParamsMemory();
      (
        reserveData.isActive,
        reserveData.isFrozen,
        reserveData.borrowingEnabled,
        reserveData.stableBorrowRateEnabled
      ) = baseData.configuration.getFlagsMemory();
      reserveData.usageAsCollateralEnabled = reserveData.baseLTVasCollateral != 0;
      (
        reserveData.variableRateSlope1,
        reserveData.variableRateSlope2,
        reserveData.stableRateSlope1,
        reserveData.stableRateSlope2
      ) = getInterestRateStrategySlopes(
        DefaultReserveInterestRateStrategy(reserveData.interestRateStrategyAddress)
      );

      // incentives
      if (address(0) != address(incentivesController)) {
        (
          reserveData.aEmissionPerSecond,
          reserveData.aIncentivesLastUpdateTimestamp,
          reserveData.aTokenIncentivesIndex
        ) = incentivesController.getAssetData(reserveData.aTokenAddress);

        (
          reserveData.sEmissionPerSecond,
          reserveData.sIncentivesLastUpdateTimestamp,
          reserveData.sTokenIncentivesIndex
        ) = incentivesController.getAssetData(reserveData.stableDebtTokenAddress);

        (
          reserveData.vEmissionPerSecond,
          reserveData.vIncentivesLastUpdateTimestamp,
          reserveData.vTokenIncentivesIndex
        ) = incentivesController.getAssetData(reserveData.variableDebtTokenAddress);
      }

      if (user != address(0)) {
        // incentives
        if (address(0) != address(incentivesController)) {
          userReservesData[i].aTokenincentivesUserIndex = incentivesController.getUserAssetData(
            user,
            reserveData.aTokenAddress
          );
          userReservesData[i].vTokenincentivesUserIndex = incentivesController.getUserAssetData(
            user,
            reserveData.variableDebtTokenAddress
          );
          userReservesData[i].sTokenincentivesUserIndex = incentivesController.getUserAssetData(
            user,
            reserveData.stableDebtTokenAddress
          );
        }
        // user reserve data
        userReservesData[i].underlyingAsset = reserveData.underlyingAsset;
        userReservesData[i].scaledATokenBalance = IAToken(reserveData.aTokenAddress)
          .scaledBalanceOf(user);
        userReservesData[i].usageAsCollateralEnabledOnUser = userConfig.isUsingAsCollateral(i);

        if (userConfig.isBorrowing(i)) {
          userReservesData[i].scaledVariableDebt = IVariableDebtToken(
            reserveData
              .variableDebtTokenAddress
          )
            .scaledBalanceOf(user);
          userReservesData[i].principalStableDebt = IStableDebtToken(
            reserveData
              .stableDebtTokenAddress
          )
            .principalBalanceOf(user);
          if (userReservesData[i].principalStableDebt != 0) {
            userReservesData[i].stableBorrowRate = IStableDebtToken(
              reserveData
                .stableDebtTokenAddress
            )
              .getUserStableRate(user);
            userReservesData[i].stableBorrowLastUpdateTimestamp = IStableDebtToken(
              reserveData
                .stableDebtTokenAddress
            )
              .getUserLastUpdated(user);
          }
        }
      }
    }

    return (
      reservesData,
      userReservesData,
      oracle.getAssetPrice(MOCK_USD_ADDRESS),
      incentivesController.getUserUnclaimedRewards(user)
    );
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {ILendingPoolAddressesProvider} from '../../interfaces/ILendingPoolAddressesProvider.sol';
import {IAaveIncentivesController} from '../../interfaces/IAaveIncentivesController.sol';

interface IUiPoolDataProvider {
  struct AggregatedReserveData {
    address underlyingAsset;
    string name;
    string symbol;
    uint256 decimals;
    uint256 baseLTVasCollateral;
    uint256 reserveLiquidationThreshold;
    uint256 reserveLiquidationBonus;
    uint256 reserveFactor;
    bool usageAsCollateralEnabled;
    bool borrowingEnabled;
    bool stableBorrowRateEnabled;
    bool isActive;
    bool isFrozen;
    // base data
    uint128 liquidityIndex;
    uint128 variableBorrowIndex;
    uint128 liquidityRate;
    uint128 variableBorrowRate;
    uint128 stableBorrowRate;
    uint40 lastUpdateTimestamp;
    address aTokenAddress;
    address stableDebtTokenAddress;
    address variableDebtTokenAddress;
    address interestRateStrategyAddress;
    //
    uint256 availableLiquidity;
    uint256 totalPrincipalStableDebt;
    uint256 averageStableRate;
    uint256 stableDebtLastUpdateTimestamp;
    uint256 totalScaledVariableDebt;
    uint256 priceInEth;
    uint256 variableRateSlope1;
    uint256 variableRateSlope2;
    uint256 stableRateSlope1;
    uint256 stableRateSlope2;
    // incentives
    uint256 aEmissionPerSecond;
    uint256 vEmissionPerSecond;
    uint256 sEmissionPerSecond;
    uint256 aIncentivesLastUpdateTimestamp;
    uint256 vIncentivesLastUpdateTimestamp;
    uint256 sIncentivesLastUpdateTimestamp;
    uint256 aTokenIncentivesIndex;
    uint256 vTokenIncentivesIndex;
    uint256 sTokenIncentivesIndex;
  }

  struct UserReserveData {
    address underlyingAsset;
    uint256 scaledATokenBalance;
    bool usageAsCollateralEnabledOnUser;
    uint256 stableBorrowRate;
    uint256 scaledVariableDebt;
    uint256 principalStableDebt;
    uint256 stableBorrowLastUpdateTimestamp;
    // incentives
    uint256 aTokenincentivesUserIndex;
    uint256 vTokenincentivesUserIndex;
    uint256 sTokenincentivesUserIndex;
  }

  function getReservesData(ILendingPoolAddressesProvider provider, address user)
    external
    view
    returns (
      AggregatedReserveData[] memory,
      UserReserveData[] memory,
      uint256,
      uint256
    );
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {IERC20Detailed} from '../dependencies/openzeppelin/contracts/IERC20Detailed.sol';
import {ILendingPoolAddressesProvider} from '../interfaces/ILendingPoolAddressesProvider.sol';
import {ILendingPool} from '../interfaces/ILendingPool.sol';
import {IStableDebtToken} from '../interfaces/IStableDebtToken.sol';
import {IVariableDebtToken} from '../interfaces/IVariableDebtToken.sol';
import {ReserveConfiguration} from '../protocol/libraries/configuration/ReserveConfiguration.sol';
import {UserConfiguration} from '../protocol/libraries/configuration/UserConfiguration.sol';
import {DataTypes} from '../protocol/libraries/types/DataTypes.sol';

contract AaveProtocolDataProvider {
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;
  using UserConfiguration for DataTypes.UserConfigurationMap;

  address constant MKR = 0x9f8F72aA9304c8B593d555F12eF6589cC3A579A2;
  address constant ETH = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;

  struct TokenData {
    string symbol;
    address tokenAddress;
  }

  ILendingPoolAddressesProvider public immutable ADDRESSES_PROVIDER;

  constructor(ILendingPoolAddressesProvider addressesProvider) public {
    ADDRESSES_PROVIDER = addressesProvider;
  }

  function getAllReservesTokens() external view returns (TokenData[] memory) {
    ILendingPool pool = ILendingPool(ADDRESSES_PROVIDER.getLendingPool());
    address[] memory reserves = pool.getReservesList();
    TokenData[] memory reservesTokens = new TokenData[](reserves.length);
    for (uint256 i = 0; i < reserves.length; i++) {
      if (reserves[i] == MKR) {
        reservesTokens[i] = TokenData({symbol: 'MKR', tokenAddress: reserves[i]});
        continue;
      }
      if (reserves[i] == ETH) {
        reservesTokens[i] = TokenData({symbol: 'ETH', tokenAddress: reserves[i]});
        continue;
      }
      reservesTokens[i] = TokenData({
        symbol: IERC20Detailed(reserves[i]).symbol(),
        tokenAddress: reserves[i]
      });
    }
    return reservesTokens;
  }

  function getAllATokens() external view returns (TokenData[] memory) {
    ILendingPool pool = ILendingPool(ADDRESSES_PROVIDER.getLendingPool());
    address[] memory reserves = pool.getReservesList();
    TokenData[] memory aTokens = new TokenData[](reserves.length);
    for (uint256 i = 0; i < reserves.length; i++) {
      DataTypes.ReserveData memory reserveData = pool.getReserveData(reserves[i]);
      aTokens[i] = TokenData({
        symbol: IERC20Detailed(reserveData.aTokenAddress).symbol(),
        tokenAddress: reserveData.aTokenAddress
      });
    }
    return aTokens;
  }

  function getReserveConfigurationData(address asset)
    external
    view
    returns (
      uint256 decimals,
      uint256 ltv,
      uint256 liquidationThreshold,
      uint256 liquidationBonus,
      uint256 reserveFactor,
      bool usageAsCollateralEnabled,
      bool borrowingEnabled,
      bool stableBorrowRateEnabled,
      bool isActive,
      bool isFrozen
    )
  {
    DataTypes.ReserveConfigurationMap memory configuration =
      ILendingPool(ADDRESSES_PROVIDER.getLendingPool()).getConfiguration(asset);

    (ltv, liquidationThreshold, liquidationBonus, decimals, reserveFactor) = configuration
      .getParamsMemory();

    (isActive, isFrozen, borrowingEnabled, stableBorrowRateEnabled) = configuration
      .getFlagsMemory();

    usageAsCollateralEnabled = liquidationThreshold > 0;
  }

  function getReserveData(address asset)
    external
    view
    returns (
      uint256 availableLiquidity,
      uint256 totalStableDebt,
      uint256 totalVariableDebt,
      uint256 liquidityRate,
      uint256 variableBorrowRate,
      uint256 stableBorrowRate,
      uint256 averageStableBorrowRate,
      uint256 liquidityIndex,
      uint256 variableBorrowIndex,
      uint40 lastUpdateTimestamp
    )
  {
    DataTypes.ReserveData memory reserve =
      ILendingPool(ADDRESSES_PROVIDER.getLendingPool()).getReserveData(asset);

    return (
      IERC20Detailed(asset).balanceOf(reserve.aTokenAddress),
      IERC20Detailed(reserve.stableDebtTokenAddress).totalSupply(),
      IERC20Detailed(reserve.variableDebtTokenAddress).totalSupply(),
      reserve.currentLiquidityRate,
      reserve.currentVariableBorrowRate,
      reserve.currentStableBorrowRate,
      IStableDebtToken(reserve.stableDebtTokenAddress).getAverageStableRate(),
      reserve.liquidityIndex,
      reserve.variableBorrowIndex,
      reserve.lastUpdateTimestamp
    );
  }

  function getUserReserveData(address asset, address user)
    external
    view
    returns (
      uint256 currentATokenBalance,
      uint256 currentStableDebt,
      uint256 currentVariableDebt,
      uint256 principalStableDebt,
      uint256 scaledVariableDebt,
      uint256 stableBorrowRate,
      uint256 liquidityRate,
      uint40 stableRateLastUpdated,
      bool usageAsCollateralEnabled
    )
  {
    DataTypes.ReserveData memory reserve =
      ILendingPool(ADDRESSES_PROVIDER.getLendingPool()).getReserveData(asset);

    DataTypes.UserConfigurationMap memory userConfig =
      ILendingPool(ADDRESSES_PROVIDER.getLendingPool()).getUserConfiguration(user);

    currentATokenBalance = IERC20Detailed(reserve.aTokenAddress).balanceOf(user);
    currentVariableDebt = IERC20Detailed(reserve.variableDebtTokenAddress).balanceOf(user);
    currentStableDebt = IERC20Detailed(reserve.stableDebtTokenAddress).balanceOf(user);
    principalStableDebt = IStableDebtToken(reserve.stableDebtTokenAddress).principalBalanceOf(user);
    scaledVariableDebt = IVariableDebtToken(reserve.variableDebtTokenAddress).scaledBalanceOf(user);
    liquidityRate = reserve.currentLiquidityRate;
    stableBorrowRate = IStableDebtToken(reserve.stableDebtTokenAddress).getUserStableRate(user);
    stableRateLastUpdated = IStableDebtToken(reserve.stableDebtTokenAddress).getUserLastUpdated(
      user
    );
    usageAsCollateralEnabled = userConfig.isUsingAsCollateral(reserve.id);
  }

  function getReserveTokensAddresses(address asset)
    external
    view
    returns (
      address aTokenAddress,
      address stableDebtTokenAddress,
      address variableDebtTokenAddress
    )
  {
    DataTypes.ReserveData memory reserve =
      ILendingPool(ADDRESSES_PROVIDER.getLendingPool()).getReserveData(asset);

    return (
      reserve.aTokenAddress,
      reserve.stableDebtTokenAddress,
      reserve.variableDebtTokenAddress
    );
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IVariableDebtToken} from '../../interfaces/IVariableDebtToken.sol';
import {WadRayMath} from '../libraries/math/WadRayMath.sol';
import {Errors} from '../libraries/helpers/Errors.sol';
import {DebtTokenBase} from './base/DebtTokenBase.sol';
import {ILendingPool} from '../../interfaces/ILendingPool.sol';
import {IAaveIncentivesController} from '../../interfaces/IAaveIncentivesController.sol';

/**
 * @title VariableDebtToken
 * @notice Implements a variable debt token to track the borrowing positions of users
 * at variable rate mode
 * @author Aave
 **/
contract VariableDebtToken is DebtTokenBase, IVariableDebtToken {
  using WadRayMath for uint256;

  uint256 public constant DEBT_TOKEN_REVISION = 0x1;

  ILendingPool internal _pool;
  address internal _underlyingAsset;
  IAaveIncentivesController internal _incentivesController;

  /**
   * @dev Initializes the debt token.
   * @param pool The address of the lending pool where this aToken will be used
   * @param underlyingAsset The address of the underlying asset of this aToken (E.g. WETH for aWETH)
   * @param incentivesController The smart contract managing potential incentives distribution
   * @param debtTokenDecimals The decimals of the debtToken, same as the underlying asset's
   * @param debtTokenName The name of the token
   * @param debtTokenSymbol The symbol of the token
   */
  function initialize(
    ILendingPool pool,
    address underlyingAsset,
    IAaveIncentivesController incentivesController,
    uint8 debtTokenDecimals,
    string memory debtTokenName,
    string memory debtTokenSymbol,
    bytes calldata params
  ) public override initializer {
    _setName(debtTokenName);
    _setSymbol(debtTokenSymbol);
    _setDecimals(debtTokenDecimals);

    _pool = pool;
    _underlyingAsset = underlyingAsset;
    _incentivesController = incentivesController;

    emit Initialized(
      underlyingAsset,
      address(pool),
      address(incentivesController),
      debtTokenDecimals,
      debtTokenName,
      debtTokenSymbol,
      params
    );
  }

  /**
   * @dev Gets the revision of the stable debt token implementation
   * @return The debt token implementation revision
   **/
  function getRevision() internal pure virtual override returns (uint256) {
    return DEBT_TOKEN_REVISION;
  }

  /**
   * @dev Calculates the accumulated debt balance of the user
   * @return The debt balance of the user
   **/
  function balanceOf(address user) public view virtual override returns (uint256) {
    uint256 scaledBalance = super.balanceOf(user);

    if (scaledBalance == 0) {
      return 0;
    }

    return scaledBalance.rayMul(_pool.getReserveNormalizedVariableDebt(_underlyingAsset));
  }

  /**
   * @dev Mints debt token to the `onBehalfOf` address
   * -  Only callable by the LendingPool
   * @param user The address receiving the borrowed underlying, being the delegatee in case
   * of credit delegate, or same as `onBehalfOf` otherwise
   * @param onBehalfOf The address receiving the debt tokens
   * @param amount The amount of debt being minted
   * @param index The variable debt index of the reserve
   * @return `true` if the the previous balance of the user is 0
   **/
  function mint(
    address user,
    address onBehalfOf,
    uint256 amount,
    uint256 index
  ) external override onlyLendingPool returns (bool) {
    if (user != onBehalfOf) {
      _decreaseBorrowAllowance(onBehalfOf, user, amount);
    }

    uint256 previousBalance = super.balanceOf(onBehalfOf);
    uint256 amountScaled = amount.rayDiv(index);
    require(amountScaled != 0, Errors.CT_INVALID_MINT_AMOUNT);

    _mint(onBehalfOf, amountScaled);

    emit Transfer(address(0), onBehalfOf, amount);
    emit Mint(user, onBehalfOf, amount, index);

    return previousBalance == 0;
  }

  /**
   * @dev Burns user variable debt
   * - Only callable by the LendingPool
   * @param user The user whose debt is getting burned
   * @param amount The amount getting burned
   * @param index The variable debt index of the reserve
   **/
  function burn(
    address user,
    uint256 amount,
    uint256 index
  ) external override onlyLendingPool {
    uint256 amountScaled = amount.rayDiv(index);
    require(amountScaled != 0, Errors.CT_INVALID_BURN_AMOUNT);

    _burn(user, amountScaled);

    emit Transfer(user, address(0), amount);
    emit Burn(user, amount, index);
  }

  /**
   * @dev Returns the principal debt balance of the user from
   * @return The debt balance of the user since the last burn/mint action
   **/
  function scaledBalanceOf(address user) public view virtual override returns (uint256) {
    return super.balanceOf(user);
  }

  /**
   * @dev Returns the total supply of the variable debt token. Represents the total debt accrued by the users
   * @return The total supply
   **/
  function totalSupply() public view virtual override returns (uint256) {
    return super.totalSupply().rayMul(_pool.getReserveNormalizedVariableDebt(_underlyingAsset));
  }

  /**
   * @dev Returns the scaled total supply of the variable debt token. Represents sum(debt/index)
   * @return the scaled total supply
   **/
  function scaledTotalSupply() public view virtual override returns (uint256) {
    return super.totalSupply();
  }

  /**
   * @dev Returns the principal balance of the user and principal total supply.
   * @param user The address of the user
   * @return The principal balance of the user
   * @return The principal total supply
   **/
  function getScaledUserBalanceAndSupply(address user)
    external
    view
    override
    returns (uint256, uint256)
  {
    return (super.balanceOf(user), super.totalSupply());
  }

  /**
   * @dev Returns the address of the underlying asset of this aToken (E.g. WETH for aWETH)
   **/
  function UNDERLYING_ASSET_ADDRESS() public view returns (address) {
    return _underlyingAsset;
  }

  /**
   * @dev Returns the address of the incentives controller contract
   **/
  function getIncentivesController() external view override returns (IAaveIncentivesController) {
    return _getIncentivesController();
  }

  /**
   * @dev Returns the address of the lending pool where this aToken is used
   **/
  function POOL() public view returns (ILendingPool) {
    return _pool;
  }

  function _getIncentivesController() internal view override returns (IAaveIncentivesController) {
    return _incentivesController;
  }

  function _getUnderlyingAssetAddress() internal view override returns (address) {
    return _underlyingAsset;
  }

  function _getLendingPool() internal view override returns (ILendingPool) {
    return _pool;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {ILendingPool} from '../../../interfaces/ILendingPool.sol';
import {ICreditDelegationToken} from '../../../interfaces/ICreditDelegationToken.sol';
import {
  VersionedInitializable
} from '../../libraries/aave-upgradeability/VersionedInitializable.sol';
import {IncentivizedERC20} from '../IncentivizedERC20.sol';
import {Errors} from '../../libraries/helpers/Errors.sol';

/**
 * @title DebtTokenBase
 * @notice Base contract for different types of debt tokens, like StableDebtToken or VariableDebtToken
 * @author Aave
 */

abstract contract DebtTokenBase is
  IncentivizedERC20('DEBTTOKEN_IMPL', 'DEBTTOKEN_IMPL', 0),
  VersionedInitializable,
  ICreditDelegationToken
{
  mapping(address => mapping(address => uint256)) internal _borrowAllowances;

  /**
   * @dev Only lending pool can call functions marked by this modifier
   **/
  modifier onlyLendingPool {
    require(_msgSender() == address(_getLendingPool()), Errors.CT_CALLER_MUST_BE_LENDING_POOL);
    _;
  }

  /**
   * @dev delegates borrowing power to a user on the specific debt token
   * @param delegatee the address receiving the delegated borrowing power
   * @param amount the maximum amount being delegated. Delegation will still
   * respect the liquidation constraints (even if delegated, a delegatee cannot
   * force a delegator HF to go below 1)
   **/
  function approveDelegation(address delegatee, uint256 amount) external override {
    _borrowAllowances[_msgSender()][delegatee] = amount;
    emit BorrowAllowanceDelegated(_msgSender(), delegatee, _getUnderlyingAssetAddress(), amount);
  }

  /**
   * @dev returns the borrow allowance of the user
   * @param fromUser The user to giving allowance
   * @param toUser The user to give allowance to
   * @return the current allowance of toUser
   **/
  function borrowAllowance(address fromUser, address toUser)
    external
    view
    override
    returns (uint256)
  {
    return _borrowAllowances[fromUser][toUser];
  }

  /**
   * @dev Being non transferrable, the debt token does not implement any of the
   * standard ERC20 functions for transfer and allowance.
   **/
  function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
    recipient;
    amount;
    revert('TRANSFER_NOT_SUPPORTED');
  }

  function allowance(address owner, address spender)
    public
    view
    virtual
    override
    returns (uint256)
  {
    owner;
    spender;
    revert('ALLOWANCE_NOT_SUPPORTED');
  }

  function approve(address spender, uint256 amount) public virtual override returns (bool) {
    spender;
    amount;
    revert('APPROVAL_NOT_SUPPORTED');
  }

  function transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) public virtual override returns (bool) {
    sender;
    recipient;
    amount;
    revert('TRANSFER_NOT_SUPPORTED');
  }

  function increaseAllowance(address spender, uint256 addedValue)
    public
    virtual
    override
    returns (bool)
  {
    spender;
    addedValue;
    revert('ALLOWANCE_NOT_SUPPORTED');
  }

  function decreaseAllowance(address spender, uint256 subtractedValue)
    public
    virtual
    override
    returns (bool)
  {
    spender;
    subtractedValue;
    revert('ALLOWANCE_NOT_SUPPORTED');
  }

  function _decreaseBorrowAllowance(
    address delegator,
    address delegatee,
    uint256 amount
  ) internal {
    uint256 newAllowance =
      _borrowAllowances[delegator][delegatee].sub(amount, Errors.BORROW_ALLOWANCE_NOT_ENOUGH);

    _borrowAllowances[delegator][delegatee] = newAllowance;

    emit BorrowAllowanceDelegated(delegator, delegatee, _getUnderlyingAssetAddress(), newAllowance);
  }

  function _getUnderlyingAssetAddress() internal view virtual returns (address);

  function _getLendingPool() internal view virtual returns (ILendingPool);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

interface ICreditDelegationToken {
  event BorrowAllowanceDelegated(
    address indexed fromUser,
    address indexed toUser,
    address asset,
    uint256 amount
  );

  /**
   * @dev delegates borrowing power to a user on the specific debt token
   * @param delegatee the address receiving the delegated borrowing power
   * @param amount the maximum amount being delegated. Delegation will still
   * respect the liquidation constraints (even if delegated, a delegatee cannot
   * force a delegator HF to go below 1)
   **/
  function approveDelegation(address delegatee, uint256 amount) external;

  /**
   * @dev returns the borrow allowance of the user
   * @param fromUser The user to giving allowance
   * @param toUser The user to give allowance to
   * @return the current allowance of toUser
   **/
  function borrowAllowance(address fromUser, address toUser) external view returns (uint256);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {Context} from '../../dependencies/openzeppelin/contracts/Context.sol';
import {IERC20} from '../../dependencies/openzeppelin/contracts/IERC20.sol';
import {IERC20Detailed} from '../../dependencies/openzeppelin/contracts/IERC20Detailed.sol';
import {SafeMath} from '../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {IAaveIncentivesController} from '../../interfaces/IAaveIncentivesController.sol';

/**
 * @title ERC20
 * @notice Basic ERC20 implementation
 * @author Aave, inspired by the Openzeppelin ERC20 implementation
 **/
abstract contract IncentivizedERC20 is Context, IERC20, IERC20Detailed {
  using SafeMath for uint256;

  mapping(address => uint256) internal _balances;

  mapping(address => mapping(address => uint256)) private _allowances;
  uint256 internal _totalSupply;
  string private _name;
  string private _symbol;
  uint8 private _decimals;

  constructor(
    string memory name,
    string memory symbol,
    uint8 decimals
  ) public {
    _name = name;
    _symbol = symbol;
    _decimals = decimals;
  }

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

  /**
   * @return The symbol of the token
   **/
  function symbol() public view override returns (string memory) {
    return _symbol;
  }

  /**
   * @return The decimals of the token
   **/
  function decimals() public view override returns (uint8) {
    return _decimals;
  }

  /**
   * @return The total supply of the token
   **/
  function totalSupply() public view virtual override returns (uint256) {
    return _totalSupply;
  }

  /**
   * @return The balance of the token
   **/
  function balanceOf(address account) public view virtual override returns (uint256) {
    return _balances[account];
  }

  /**
   * @return Abstract function implemented by the child aToken/debtToken. 
   * Done this way in order to not break compatibility with previous versions of aTokens/debtTokens
   **/
  function _getIncentivesController() internal view virtual returns(IAaveIncentivesController);

  /**
   * @dev Executes a transfer of tokens from _msgSender() to recipient
   * @param recipient The recipient of the tokens
   * @param amount The amount of tokens being transferred
   * @return `true` if the transfer succeeds, `false` otherwise
   **/
  function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
    _transfer(_msgSender(), recipient, amount);
    emit Transfer(_msgSender(), recipient, amount);
    return true;
  }

  /**
   * @dev Returns the allowance of spender on the tokens owned by owner
   * @param owner The owner of the tokens
   * @param spender The user allowed to spend the owner's tokens
   * @return The amount of owner's tokens spender is allowed to spend
   **/
  function allowance(address owner, address spender)
    public
    view
    virtual
    override
    returns (uint256)
  {
    return _allowances[owner][spender];
  }

  /**
   * @dev Allows `spender` to spend the tokens owned by _msgSender()
   * @param spender The user allowed to spend _msgSender() tokens
   * @return `true`
   **/
  function approve(address spender, uint256 amount) public virtual override returns (bool) {
    _approve(_msgSender(), spender, amount);
    return true;
  }

  /**
   * @dev Executes a transfer of token from sender to recipient, if _msgSender() is allowed to do so
   * @param sender The owner of the tokens
   * @param recipient The recipient of the tokens
   * @param amount The amount of tokens being transferred
   * @return `true` if the transfer succeeds, `false` otherwise
   **/
  function transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) public virtual override returns (bool) {
    _transfer(sender, recipient, amount);
    _approve(
      sender,
      _msgSender(),
      _allowances[sender][_msgSender()].sub(amount, 'ERC20: transfer amount exceeds allowance')
    );
    emit Transfer(sender, recipient, amount);
    return true;
  }

  /**
   * @dev Increases the allowance of spender to spend _msgSender() tokens
   * @param spender The user allowed to spend on behalf of _msgSender()
   * @param addedValue The amount being added to the allowance
   * @return `true`
   **/
  function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
    _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
    return true;
  }

  /**
   * @dev Decreases the allowance of spender to spend _msgSender() tokens
   * @param spender The user allowed to spend on behalf of _msgSender()
   * @param subtractedValue The amount being subtracted to the allowance
   * @return `true`
   **/
  function decreaseAllowance(address spender, uint256 subtractedValue)
    public
    virtual
    returns (bool)
  {
    _approve(
      _msgSender(),
      spender,
      _allowances[_msgSender()][spender].sub(
        subtractedValue,
        'ERC20: decreased allowance below zero'
      )
    );
    return true;
  }

  function _transfer(
    address sender,
    address recipient,
    uint256 amount
  ) internal virtual {
    require(sender != address(0), 'ERC20: transfer from the zero address');
    require(recipient != address(0), 'ERC20: transfer to the zero address');

    _beforeTokenTransfer(sender, recipient, amount);

    uint256 oldSenderBalance = _balances[sender];
    _balances[sender] = oldSenderBalance.sub(amount, 'ERC20: transfer amount exceeds balance');
    uint256 oldRecipientBalance = _balances[recipient];
    _balances[recipient] = _balances[recipient].add(amount);

    if (address(_getIncentivesController()) != address(0)) {
      uint256 currentTotalSupply = _totalSupply;
      _getIncentivesController().handleAction(sender, currentTotalSupply, oldSenderBalance);
      if (sender != recipient) {
        _getIncentivesController().handleAction(recipient, currentTotalSupply, oldRecipientBalance);
      }
    }
  }

  function _mint(address account, uint256 amount) internal virtual {
    require(account != address(0), 'ERC20: mint to the zero address');

    _beforeTokenTransfer(address(0), account, amount);

    uint256 oldTotalSupply = _totalSupply;
    _totalSupply = oldTotalSupply.add(amount);

    uint256 oldAccountBalance = _balances[account];
    _balances[account] = oldAccountBalance.add(amount);

    if (address(_getIncentivesController()) != address(0)) {
      _getIncentivesController().handleAction(account, oldTotalSupply, oldAccountBalance);
    }
  }

  function _burn(address account, uint256 amount) internal virtual {
    require(account != address(0), 'ERC20: burn from the zero address');

    _beforeTokenTransfer(account, address(0), amount);

    uint256 oldTotalSupply = _totalSupply;
    _totalSupply = oldTotalSupply.sub(amount);

    uint256 oldAccountBalance = _balances[account];
    _balances[account] = oldAccountBalance.sub(amount, 'ERC20: burn amount exceeds balance');

    if (address(_getIncentivesController()) != address(0)) {
      _getIncentivesController().handleAction(account, oldTotalSupply, oldAccountBalance);
    }
  }

  function _approve(
    address owner,
    address spender,
    uint256 amount
  ) internal virtual {
    require(owner != address(0), 'ERC20: approve from the zero address');
    require(spender != address(0), 'ERC20: approve to the zero address');

    _allowances[owner][spender] = amount;
    emit Approval(owner, spender, amount);
  }

  function _setName(string memory newName) internal {
    _name = newName;
  }

  function _setSymbol(string memory newSymbol) internal {
    _symbol = newSymbol;
  }

  function _setDecimals(uint8 newDecimals) internal {
    _decimals = newDecimals;
  }

  function _beforeTokenTransfer(
    address from,
    address to,
    uint256 amount
  ) internal virtual {}
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {VariableDebtToken} from '../../protocol/tokenization/VariableDebtToken.sol';

contract MockVariableDebtToken is VariableDebtToken {
  function getRevision() internal pure override returns (uint256) {
    return 0x2;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {AToken} from '../../protocol/tokenization/AToken.sol';
import {ILendingPool} from '../../interfaces/ILendingPool.sol';
import {IAaveIncentivesController} from '../../interfaces/IAaveIncentivesController.sol';

contract MockAToken is AToken {
  function getRevision() internal pure override returns (uint256) {
    return 0x2;
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {IERC20} from '../../dependencies/openzeppelin/contracts/IERC20.sol';
import {SafeERC20} from '../../dependencies/openzeppelin/contracts/SafeERC20.sol';
import {ILendingPool} from '../../interfaces/ILendingPool.sol';
import {IAToken} from '../../interfaces/IAToken.sol';
import {WadRayMath} from '../libraries/math/WadRayMath.sol';
import {Errors} from '../libraries/helpers/Errors.sol';
import {VersionedInitializable} from '../libraries/aave-upgradeability/VersionedInitializable.sol';
import {IncentivizedERC20} from './IncentivizedERC20.sol';
import {IAaveIncentivesController} from '../../interfaces/IAaveIncentivesController.sol';

/**
 * @title Aave ERC20 AToken
 * @dev Implementation of the interest bearing token for the Aave protocol
 * @author Aave
 */
contract AToken is
  VersionedInitializable,
  IncentivizedERC20('ATOKEN_IMPL', 'ATOKEN_IMPL', 0),
  IAToken
{
  using WadRayMath for uint256;
  using SafeERC20 for IERC20;

  bytes public constant EIP712_REVISION = bytes('1');
  bytes32 internal constant EIP712_DOMAIN =
    keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)');
  bytes32 public constant PERMIT_TYPEHASH =
    keccak256('Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)');

  uint256 public constant ATOKEN_REVISION = 0x1;

  /// @dev owner => next valid nonce to submit with permit()
  mapping(address => uint256) public _nonces;

  bytes32 public DOMAIN_SEPARATOR;

  ILendingPool internal _pool;
  address internal _treasury;
  address internal _underlyingAsset;
  IAaveIncentivesController internal _incentivesController;

  modifier onlyLendingPool {
    require(_msgSender() == address(_pool), Errors.CT_CALLER_MUST_BE_LENDING_POOL);
    _;
  }

  function getRevision() internal pure virtual override returns (uint256) {
    return ATOKEN_REVISION;
  }

  /**
   * @dev Initializes the aToken
   * @param pool The address of the lending pool where this aToken will be used
   * @param treasury The address of the Aave treasury, receiving the fees on this aToken
   * @param underlyingAsset The address of the underlying asset of this aToken (E.g. WETH for aWETH)
   * @param incentivesController The smart contract managing potential incentives distribution
   * @param aTokenDecimals The decimals of the aToken, same as the underlying asset's
   * @param aTokenName The name of the aToken
   * @param aTokenSymbol The symbol of the aToken
   */
  function initialize(
    ILendingPool pool,
    address treasury,
    address underlyingAsset,
    IAaveIncentivesController incentivesController,
    uint8 aTokenDecimals,
    string calldata aTokenName,
    string calldata aTokenSymbol,
    bytes calldata params
  ) external override initializer {
    uint256 chainId;

    //solium-disable-next-line
    assembly {
      chainId := chainid()
    }

    DOMAIN_SEPARATOR = keccak256(
      abi.encode(
        EIP712_DOMAIN,
        keccak256(bytes(aTokenName)),
        keccak256(EIP712_REVISION),
        chainId,
        address(this)
      )
    );

    _setName(aTokenName);
    _setSymbol(aTokenSymbol);
    _setDecimals(aTokenDecimals);

    _pool = pool;
    _treasury = treasury;
    _underlyingAsset = underlyingAsset;
    _incentivesController = incentivesController;

    emit Initialized(
      underlyingAsset,
      address(pool),
      treasury,
      address(incentivesController),
      aTokenDecimals,
      aTokenName,
      aTokenSymbol,
      params
    );
  }

  /**
   * @dev Burns aTokens from `user` and sends the equivalent amount of underlying to `receiverOfUnderlying`
   * - Only callable by the LendingPool, as extra state updates there need to be managed
   * @param user The owner of the aTokens, getting them burned
   * @param receiverOfUnderlying The address that will receive the underlying
   * @param amount The amount being burned
   * @param index The new liquidity index of the reserve
   **/
  function burn(
    address user,
    address receiverOfUnderlying,
    uint256 amount,
    uint256 index
  ) external override onlyLendingPool {
    uint256 amountScaled = amount.rayDiv(index);
    require(amountScaled != 0, Errors.CT_INVALID_BURN_AMOUNT);
    _burn(user, amountScaled);

    IERC20(_underlyingAsset).safeTransfer(receiverOfUnderlying, amount);

    emit Transfer(user, address(0), amount);
    emit Burn(user, receiverOfUnderlying, amount, index);
  }

  /**
   * @dev Mints `amount` aTokens to `user`
   * - Only callable by the LendingPool, as extra state updates there need to be managed
   * @param user The address receiving the minted tokens
   * @param amount The amount of tokens getting minted
   * @param index The new liquidity index of the reserve
   * @return `true` if the the previous balance of the user was 0
   */
  function mint(
    address user,
    uint256 amount,
    uint256 index
  ) external override onlyLendingPool returns (bool) {
    uint256 previousBalance = super.balanceOf(user);

    uint256 amountScaled = amount.rayDiv(index);
    require(amountScaled != 0, Errors.CT_INVALID_MINT_AMOUNT);
    _mint(user, amountScaled);

    emit Transfer(address(0), user, amount);
    emit Mint(user, amount, index);

    return previousBalance == 0;
  }

  /**
   * @dev Mints aTokens to the reserve treasury
   * - Only callable by the LendingPool
   * @param amount The amount of tokens getting minted
   * @param index The new liquidity index of the reserve
   */
  function mintToTreasury(uint256 amount, uint256 index) external override onlyLendingPool {
    if (amount == 0) {
      return;
    }

    address treasury = _treasury;

    // Compared to the normal mint, we don't check for rounding errors.
    // The amount to mint can easily be very small since it is a fraction of the interest ccrued.
    // In that case, the treasury will experience a (very small) loss, but it
    // wont cause potentially valid transactions to fail.
    _mint(treasury, amount.rayDiv(index));

    emit Transfer(address(0), treasury, amount);
    emit Mint(treasury, amount, index);
  }

  /**
   * @dev Transfers aTokens in the event of a borrow being liquidated, in case the liquidators reclaims the aToken
   * - Only callable by the LendingPool
   * @param from The address getting liquidated, current owner of the aTokens
   * @param to The recipient
   * @param value The amount of tokens getting transferred
   **/
  function transferOnLiquidation(
    address from,
    address to,
    uint256 value
  ) external override onlyLendingPool {
    // Being a normal transfer, the Transfer() and BalanceTransfer() are emitted
    // so no need to emit a specific event here
    _transfer(from, to, value, false);

    emit Transfer(from, to, value);
  }

  /**
   * @dev Calculates the balance of the user: principal balance + interest generated by the principal
   * @param user The user whose balance is calculated
   * @return The balance of the user
   **/
  function balanceOf(address user)
    public
    view
    override(IncentivizedERC20, IERC20)
    returns (uint256)
  {
    return super.balanceOf(user).rayMul(_pool.getReserveNormalizedIncome(_underlyingAsset));
  }

  /**
   * @dev Returns the scaled balance of the user. The scaled balance is the sum of all the
   * updated stored balance divided by the reserve's liquidity index at the moment of the update
   * @param user The user whose balance is calculated
   * @return The scaled balance of the user
   **/
  function scaledBalanceOf(address user) external view override returns (uint256) {
    return super.balanceOf(user);
  }

  /**
   * @dev Returns the scaled balance of the user and the scaled total supply.
   * @param user The address of the user
   * @return The scaled balance of the user
   * @return The scaled balance and the scaled total supply
   **/
  function getScaledUserBalanceAndSupply(address user)
    external
    view
    override
    returns (uint256, uint256)
  {
    return (super.balanceOf(user), super.totalSupply());
  }

  /**
   * @dev calculates the total supply of the specific aToken
   * since the balance of every single user increases over time, the total supply
   * does that too.
   * @return the current total supply
   **/
  function totalSupply() public view override(IncentivizedERC20, IERC20) returns (uint256) {
    uint256 currentSupplyScaled = super.totalSupply();

    if (currentSupplyScaled == 0) {
      return 0;
    }

    return currentSupplyScaled.rayMul(_pool.getReserveNormalizedIncome(_underlyingAsset));
  }

  /**
   * @dev Returns the scaled total supply of the variable debt token. Represents sum(debt/index)
   * @return the scaled total supply
   **/
  function scaledTotalSupply() public view virtual override returns (uint256) {
    return super.totalSupply();
  }

  /**
   * @dev Returns the address of the Aave treasury, receiving the fees on this aToken
   **/
  function RESERVE_TREASURY_ADDRESS() public view returns (address) {
    return _treasury;
  }

  /**
   * @dev Returns the address of the underlying asset of this aToken (E.g. WETH for aWETH)
   **/
  function UNDERLYING_ASSET_ADDRESS() public override view returns (address) {
    return _underlyingAsset;
  }

  /**
   * @dev Returns the address of the lending pool where this aToken is used
   **/
  function POOL() public view returns (ILendingPool) {
    return _pool;
  }

  /**
   * @dev For internal usage in the logic of the parent contract IncentivizedERC20
   **/
  function _getIncentivesController() internal view override returns (IAaveIncentivesController) {
    return _incentivesController;
  }

  /**
   * @dev Returns the address of the incentives controller contract
   **/
  function getIncentivesController() external view override returns (IAaveIncentivesController) {
    return _getIncentivesController();
  }

  /**
   * @dev Transfers the underlying asset to `target`. Used by the LendingPool to transfer
   * assets in borrow(), withdraw() and flashLoan()
   * @param target The recipient of the aTokens
   * @param amount The amount getting transferred
   * @return The amount transferred
   **/
  function transferUnderlyingTo(address target, uint256 amount)
    external
    override
    onlyLendingPool
    returns (uint256)
  {
    IERC20(_underlyingAsset).safeTransfer(target, amount);
    return amount;
  }

  /**
   * @dev Invoked to execute actions on the aToken side after a repayment.
   * @param user The user executing the repayment
   * @param amount The amount getting repaid
   **/
  function handleRepayment(address user, uint256 amount) external override onlyLendingPool {}

  /**
   * @dev implements the permit function as for
   * https://github.com/ethereum/EIPs/blob/8a34d644aacf0f9f8f00815307fd7dd5da07655f/EIPS/eip-2612.md
   * @param owner The owner of the funds
   * @param spender The spender
   * @param value The amount
   * @param deadline The deadline timestamp, type(uint256).max for max deadline
   * @param v Signature param
   * @param s Signature param
   * @param r Signature param
   */
  function permit(
    address owner,
    address spender,
    uint256 value,
    uint256 deadline,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external {
    require(owner != address(0), 'INVALID_OWNER');
    //solium-disable-next-line
    require(block.timestamp <= deadline, 'INVALID_EXPIRATION');
    uint256 currentValidNonce = _nonces[owner];
    bytes32 digest =
      keccak256(
        abi.encodePacked(
          '\x19\x01',
          DOMAIN_SEPARATOR,
          keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, currentValidNonce, deadline))
        )
      );
    require(owner == ecrecover(digest, v, r, s), 'INVALID_SIGNATURE');
    _nonces[owner] = currentValidNonce.add(1);
    _approve(owner, spender, value);
  }

  /**
   * @dev Transfers the aTokens between two users. Validates the transfer
   * (ie checks for valid HF after the transfer) if required
   * @param from The source address
   * @param to The destination address
   * @param amount The amount getting transferred
   * @param validate `true` if the transfer needs to be validated
   **/
  function _transfer(
    address from,
    address to,
    uint256 amount,
    bool validate
  ) internal {
    address underlyingAsset = _underlyingAsset;
    ILendingPool pool = _pool;

    uint256 index = pool.getReserveNormalizedIncome(underlyingAsset);

    uint256 fromBalanceBefore = super.balanceOf(from).rayMul(index);
    uint256 toBalanceBefore = super.balanceOf(to).rayMul(index);

    super._transfer(from, to, amount.rayDiv(index));

    if (validate) {
      pool.finalizeTransfer(underlyingAsset, from, to, amount, fromBalanceBefore, toBalanceBefore);
    }

    emit BalanceTransfer(from, to, amount, index);
  }

  /**
   * @dev Overrides the parent _transfer to force validated transfer() and transferFrom()
   * @param from The source address
   * @param to The destination address
   * @param amount The amount getting transferred
   **/
  function _transfer(
    address from,
    address to,
    uint256 amount
  ) internal override {
    _transfer(from, to, amount, true);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {ILendingPool} from '../../interfaces/ILendingPool.sol';
import {IDelegationToken} from '../../interfaces/IDelegationToken.sol';
import {Errors} from '../libraries/helpers/Errors.sol';
import {AToken} from './AToken.sol';

/**
 * @title Aave AToken enabled to delegate voting power of the underlying asset to a different address
 * @dev The underlying asset needs to be compatible with the COMP delegation interface
 * @author Aave
 */
contract DelegationAwareAToken is AToken {
  modifier onlyPoolAdmin {
    require(
      _msgSender() == ILendingPool(_pool).getAddressesProvider().getPoolAdmin(),
      Errors.CALLER_NOT_POOL_ADMIN
    );
    _;
  }

  /**
   * @dev Delegates voting power of the underlying asset to a `delegatee` address
   * @param delegatee The address that will receive the delegation
   **/
  function delegateUnderlyingTo(address delegatee) external onlyPoolAdmin {
    IDelegationToken(_underlyingAsset).delegate(delegatee);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title IDelegationToken
 * @dev Implements an interface for tokens with delegation COMP/UNI compatible
 * @author Aave
 **/
interface IDelegationToken {
  function delegate(address delegatee) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {Ownable} from '../../dependencies/openzeppelin/contracts/Ownable.sol';
import {
  ILendingPoolAddressesProviderRegistry
} from '../../interfaces/ILendingPoolAddressesProviderRegistry.sol';
import {Errors} from '../libraries/helpers/Errors.sol';

/**
 * @title LendingPoolAddressesProviderRegistry contract
 * @dev Main registry of LendingPoolAddressesProvider of multiple Aave protocol's markets
 * - Used for indexing purposes of Aave protocol's markets
 * - The id assigned to a LendingPoolAddressesProvider refers to the market it is connected with,
 *   for example with `0` for the Aave main market and `1` for the next created
 * @author Aave
 **/
contract LendingPoolAddressesProviderRegistry is Ownable, ILendingPoolAddressesProviderRegistry {
  mapping(address => uint256) private _addressesProviders;
  address[] private _addressesProvidersList;

  /**
   * @dev Returns the list of registered addresses provider
   * @return The list of addresses provider, potentially containing address(0) elements
   **/
  function getAddressesProvidersList() external view override returns (address[] memory) {
    address[] memory addressesProvidersList = _addressesProvidersList;

    uint256 maxLength = addressesProvidersList.length;

    address[] memory activeProviders = new address[](maxLength);

    for (uint256 i = 0; i < maxLength; i++) {
      if (_addressesProviders[addressesProvidersList[i]] > 0) {
        activeProviders[i] = addressesProvidersList[i];
      }
    }

    return activeProviders;
  }

  /**
   * @dev Registers an addresses provider
   * @param provider The address of the new LendingPoolAddressesProvider
   * @param id The id for the new LendingPoolAddressesProvider, referring to the market it belongs to
   **/
  function registerAddressesProvider(address provider, uint256 id) external override onlyOwner {
    require(id != 0, Errors.LPAPR_INVALID_ADDRESSES_PROVIDER_ID);

    _addressesProviders[provider] = id;
    _addToAddressesProvidersList(provider);
    emit AddressesProviderRegistered(provider);
  }

  /**
   * @dev Removes a LendingPoolAddressesProvider from the list of registered addresses provider
   * @param provider The LendingPoolAddressesProvider address
   **/
  function unregisterAddressesProvider(address provider) external override onlyOwner {
    require(_addressesProviders[provider] > 0, Errors.LPAPR_PROVIDER_NOT_REGISTERED);
    _addressesProviders[provider] = 0;
    emit AddressesProviderUnregistered(provider);
  }

  /**
   * @dev Returns the id on a registered LendingPoolAddressesProvider
   * @return The id or 0 if the LendingPoolAddressesProvider is not registered
   */
  function getAddressesProviderIdByAddress(address addressesProvider)
    external
    view
    override
    returns (uint256)
  {
    return _addressesProviders[addressesProvider];
  }

  function _addToAddressesProvidersList(address provider) internal {
    uint256 providersCount = _addressesProvidersList.length;

    for (uint256 i = 0; i < providersCount; i++) {
      if (_addressesProvidersList[i] == provider) {
        return;
      }
    }

    _addressesProvidersList.push(provider);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

/**
 * @title LendingPoolAddressesProviderRegistry contract
 * @dev Main registry of LendingPoolAddressesProvider of multiple Aave protocol's markets
 * - Used for indexing purposes of Aave protocol's markets
 * - The id assigned to a LendingPoolAddressesProvider refers to the market it is connected with,
 *   for example with `0` for the Aave main market and `1` for the next created
 * @author Aave
 **/
interface ILendingPoolAddressesProviderRegistry {
  event AddressesProviderRegistered(address indexed newAddress);
  event AddressesProviderUnregistered(address indexed newAddress);

  function getAddressesProvidersList() external view returns (address[] memory);

  function getAddressesProviderIdByAddress(address addressesProvider)
    external
    view
    returns (uint256);

  function registerAddressesProvider(address provider, uint256 id) external;

  function unregisterAddressesProvider(address provider) external;
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import {Ownable} from '../dependencies/openzeppelin/contracts/Ownable.sol';
import {IERC20} from '../dependencies/openzeppelin/contracts/IERC20.sol';

import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
import {IChainlinkAggregator} from '../interfaces/IChainlinkAggregator.sol';
import {SafeERC20} from '../dependencies/openzeppelin/contracts/SafeERC20.sol';

/// @title AaveOracle
/// @author Aave
/// @notice Proxy smart contract to get the price of an asset from a price source, with Chainlink Aggregator
///         smart contracts as primary option
/// - If the returned price by a Chainlink aggregator is <= 0, the call is forwarded to a fallbackOracle
/// - Owned by the Aave governance system, allowed to add sources for assets, replace them
///   and change the fallbackOracle
contract AaveOracle is IPriceOracleGetter, Ownable {
  using SafeERC20 for IERC20;

  event WethSet(address indexed weth);
  event AssetSourceUpdated(address indexed asset, address indexed source);
  event FallbackOracleUpdated(address indexed fallbackOracle);

  mapping(address => IChainlinkAggregator) private assetsSources;
  IPriceOracleGetter private _fallbackOracle;
  address public immutable WETH;

  /// @notice Constructor
  /// @param assets The addresses of the assets
  /// @param sources The address of the source of each asset
  /// @param fallbackOracle The address of the fallback oracle to use if the data of an
  ///        aggregator is not consistent
  constructor(
    address[] memory assets,
    address[] memory sources,
    address fallbackOracle,
    address weth
  ) public {
    _setFallbackOracle(fallbackOracle);
    _setAssetsSources(assets, sources);
    WETH = weth;
    emit WethSet(weth);
  }

  /// @notice External function called by the Aave governance to set or replace sources of assets
  /// @param assets The addresses of the assets
  /// @param sources The address of the source of each asset
  function setAssetSources(address[] calldata assets, address[] calldata sources)
    external
    onlyOwner
  {
    _setAssetsSources(assets, sources);
  }

  /// @notice Sets the fallbackOracle
  /// - Callable only by the Aave governance
  /// @param fallbackOracle The address of the fallbackOracle
  function setFallbackOracle(address fallbackOracle) external onlyOwner {
    _setFallbackOracle(fallbackOracle);
  }

  /// @notice Internal function to set the sources for each asset
  /// @param assets The addresses of the assets
  /// @param sources The address of the source of each asset
  function _setAssetsSources(address[] memory assets, address[] memory sources) internal {
    require(assets.length == sources.length, 'INCONSISTENT_PARAMS_LENGTH');
    for (uint256 i = 0; i < assets.length; i++) {
      assetsSources[assets[i]] = IChainlinkAggregator(sources[i]);
      emit AssetSourceUpdated(assets[i], sources[i]);
    }
  }

  /// @notice Internal function to set the fallbackOracle
  /// @param fallbackOracle The address of the fallbackOracle
  function _setFallbackOracle(address fallbackOracle) internal {
    _fallbackOracle = IPriceOracleGetter(fallbackOracle);
    emit FallbackOracleUpdated(fallbackOracle);
  }

  /// @notice Gets an asset price by address
  /// @param asset The asset address
  function getAssetPrice(address asset) public view override returns (uint256) {
    IChainlinkAggregator source = assetsSources[asset];

    if (asset == WETH) {
      return 1 ether;
    } else if (address(source) == address(0)) {
      return _fallbackOracle.getAssetPrice(asset);
    } else {
      int256 price = IChainlinkAggregator(source).latestAnswer();
      if (price > 0) {
        return uint256(price);
      } else {
        return _fallbackOracle.getAssetPrice(asset);
      }
    }
  }

  /// @notice Gets a list of prices from a list of assets addresses
  /// @param assets The list of assets addresses
  function getAssetsPrices(address[] calldata assets) external view returns (uint256[] memory) {
    uint256[] memory prices = new uint256[](assets.length);
    for (uint256 i = 0; i < assets.length; i++) {
      prices[i] = getAssetPrice(assets[i]);
    }
    return prices;
  }

  /// @notice Gets the address of the source for an asset address
  /// @param asset The address of the asset
  /// @return address The address of the source
  function getSourceOfAsset(address asset) external view returns (address) {
    return address(assetsSources[asset]);
  }

  /// @notice Gets the address of the fallback oracle
  /// @return address The addres of the fallback oracle
  function getFallbackOracle() external view returns (address) {
    return address(_fallbackOracle);
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

interface IChainlinkAggregator {
  function latestAnswer() external view returns (int256);

  function latestTimestamp() external view returns (uint256);

  function latestRound() external view returns (uint256);

  function getAnswer(uint256 roundId) external view returns (int256);

  function getTimestamp(uint256 roundId) external view returns (uint256);

  event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 timestamp);
  event NewRound(uint256 indexed roundId, address indexed startedBy);
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import {SafeMath} from '../../dependencies/openzeppelin/contracts/SafeMath.sol';
import {VersionedInitializable} from '../libraries/aave-upgradeability/VersionedInitializable.sol';
import {
  InitializableImmutableAdminUpgradeabilityProxy
} from '../libraries/aave-upgradeability/InitializableImmutableAdminUpgradeabilityProxy.sol';
import {ReserveConfiguration} from '../libraries/configuration/ReserveConfiguration.sol';
import {ILendingPoolAddressesProvider} from '../../interfaces/ILendingPoolAddressesProvider.sol';
import {ILendingPool} from '../../interfaces/ILendingPool.sol';
import {IERC20Detailed} from '../../dependencies/openzeppelin/contracts/IERC20Detailed.sol';
import {Errors} from '../libraries/helpers/Errors.sol';
import {PercentageMath} from '../libraries/math/PercentageMath.sol';
import {DataTypes} from '../libraries/types/DataTypes.sol';
import {IInitializableDebtToken} from '../../interfaces/IInitializableDebtToken.sol';
import {IInitializableAToken} from '../../interfaces/IInitializableAToken.sol';
import {IAaveIncentivesController} from '../../interfaces/IAaveIncentivesController.sol';
import {ILendingPoolConfigurator} from '../../interfaces/ILendingPoolConfigurator.sol';

/**
 * @title LendingPoolConfigurator contract
 * @author Aave
 * @dev Implements the configuration methods for the Aave protocol
 **/

contract LendingPoolConfigurator is VersionedInitializable, ILendingPoolConfigurator {
  using SafeMath for uint256;
  using PercentageMath for uint256;
  using ReserveConfiguration for DataTypes.ReserveConfigurationMap;

  ILendingPoolAddressesProvider internal addressesProvider;
  ILendingPool internal pool;

  modifier onlyPoolAdmin {
    require(addressesProvider.getPoolAdmin() == msg.sender, Errors.CALLER_NOT_POOL_ADMIN);
    _;
  }

  modifier onlyEmergencyAdmin {
    require(
      addressesProvider.getEmergencyAdmin() == msg.sender,
      Errors.LPC_CALLER_NOT_EMERGENCY_ADMIN
    );
    _;
  }

  uint256 internal constant CONFIGURATOR_REVISION = 0x1;

  function getRevision() internal pure override returns (uint256) {
    return CONFIGURATOR_REVISION;
  }

  function initialize(ILendingPoolAddressesProvider provider) public initializer {
    addressesProvider = provider;
    pool = ILendingPool(addressesProvider.getLendingPool());
  }

  /**
   * @dev Initializes reserves in batch
   **/
  function batchInitReserve(InitReserveInput[] calldata input) external onlyPoolAdmin {
    ILendingPool cachedPool = pool;
    for (uint256 i = 0; i < input.length; i++) {
      _initReserve(cachedPool, input[i]);
    }
  }

  function _initReserve(ILendingPool pool, InitReserveInput calldata input) internal {
    address aTokenProxyAddress =
      _initTokenWithProxy(
        input.aTokenImpl,
        abi.encodeWithSelector(
          IInitializableAToken.initialize.selector,
          pool,
          input.treasury,
          input.underlyingAsset,
          IAaveIncentivesController(input.incentivesController),
          input.underlyingAssetDecimals,
          input.aTokenName,
          input.aTokenSymbol,
          input.params
        )
      );

    address stableDebtTokenProxyAddress =
      _initTokenWithProxy(
        input.stableDebtTokenImpl,
        abi.encodeWithSelector(
          IInitializableDebtToken.initialize.selector,
          pool,
          input.underlyingAsset,
          IAaveIncentivesController(input.incentivesController),
          input.underlyingAssetDecimals,
          input.stableDebtTokenName,
          input.stableDebtTokenSymbol,
          input.params
        )
      );

    address variableDebtTokenProxyAddress =
      _initTokenWithProxy(
        input.variableDebtTokenImpl,
        abi.encodeWithSelector(
          IInitializableDebtToken.initialize.selector,
          pool,
          input.underlyingAsset,
          IAaveIncentivesController(input.incentivesController),
          input.underlyingAssetDecimals,
          input.variableDebtTokenName,
          input.variableDebtTokenSymbol,
          input.params
        )
      );

    pool.initReserve(
      input.underlyingAsset,
      aTokenProxyAddress,
      stableDebtTokenProxyAddress,
      variableDebtTokenProxyAddress,
      input.interestRateStrategyAddress
    );

    DataTypes.ReserveConfigurationMap memory currentConfig =
      pool.getConfiguration(input.underlyingAsset);

    currentConfig.setDecimals(input.underlyingAssetDecimals);

    currentConfig.setActive(true);
    currentConfig.setFrozen(false);

    pool.setConfiguration(input.underlyingAsset, currentConfig.data);

    emit ReserveInitialized(
      input.underlyingAsset,
      aTokenProxyAddress,
      stableDebtTokenProxyAddress,
      variableDebtTokenProxyAddress,
      input.interestRateStrategyAddress
    );
  }

  /**
   * @dev Updates the aToken implementation for the reserve
   **/
  function updateAToken(UpdateATokenInput calldata input) external onlyPoolAdmin {
    ILendingPool cachedPool = pool;

    DataTypes.ReserveData memory reserveData = cachedPool.getReserveData(input.asset);

    (, , , uint256 decimals, ) = cachedPool.getConfiguration(input.asset).getParamsMemory();

    bytes memory encodedCall = abi.encodeWithSelector(
        IInitializableAToken.initialize.selector,
        cachedPool,
        input.treasury,
        input.asset,
        input.incentivesController,
        decimals,
        input.name,
        input.symbol,
        input.params
      );

    _upgradeTokenImplementation(
      reserveData.aTokenAddress,
      input.implementation,
      encodedCall
    );

    emit ATokenUpgraded(input.asset, reserveData.aTokenAddress, input.implementation);
  }

  /**
   * @dev Updates the stable debt token implementation for the reserve
   **/
  function updateStableDebtToken(UpdateDebtTokenInput calldata input) external onlyPoolAdmin {
    ILendingPool cachedPool = pool;

    DataTypes.ReserveData memory reserveData = cachedPool.getReserveData(input.asset);
     
    (, , , uint256 decimals, ) = cachedPool.getConfiguration(input.asset).getParamsMemory();

    bytes memory encodedCall = abi.encodeWithSelector(
        IInitializableDebtToken.initialize.selector,
        cachedPool,
        input.asset,
        input.incentivesController,
        decimals,
        input.name,
        input.symbol,
        input.params
      );

    _upgradeTokenImplementation(
      reserveData.stableDebtTokenAddress,
      input.implementation,
      encodedCall
    );

    emit StableDebtTokenUpgraded(
      input.asset,
      reserveData.stableDebtTokenAddress,
      input.implementation
    );
  }

  /**
   * @dev Updates the variable debt token implementation for the asset
   **/
  function updateVariableDebtToken(UpdateDebtTokenInput calldata input)
    external
    onlyPoolAdmin
  {
    ILendingPool cachedPool = pool;

    DataTypes.ReserveData memory reserveData = cachedPool.getReserveData(input.asset);

    (, , , uint256 decimals, ) = cachedPool.getConfiguration(input.asset).getParamsMemory();

    bytes memory encodedCall = abi.encodeWithSelector(
        IInitializableDebtToken.initialize.selector,
        cachedPool,
        input.asset,
        input.incentivesController,
        decimals,
        input.name,
        input.symbol,
        input.params
      );

    _upgradeTokenImplementation(
      reserveData.variableDebtTokenAddress,
      input.implementation,
      encodedCall
    );

    emit VariableDebtTokenUpgraded(
      input.asset,
      reserveData.variableDebtTokenAddress,
      input.implementation
    );
  }

  /**
   * @dev Enables borrowing on a reserve
   * @param asset The address of the underlying asset of the reserve
   * @param stableBorrowRateEnabled True if stable borrow rate needs to be enabled by default on this reserve
   **/
  function enableBorrowingOnReserve(address asset, bool stableBorrowRateEnabled)
    external
    onlyPoolAdmin
  {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setBorrowingEnabled(true);
    currentConfig.setStableRateBorrowingEnabled(stableBorrowRateEnabled);

    pool.setConfiguration(asset, currentConfig.data);

    emit BorrowingEnabledOnReserve(asset, stableBorrowRateEnabled);
  }

  /**
   * @dev Disables borrowing on a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  function disableBorrowingOnReserve(address asset) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setBorrowingEnabled(false);

    pool.setConfiguration(asset, currentConfig.data);
    emit BorrowingDisabledOnReserve(asset);
  }

  /**
   * @dev Configures the reserve collateralization parameters
   * all the values are expressed in percentages with two decimals of precision. A valid value is 10000, which means 100.00%
   * @param asset The address of the underlying asset of the reserve
   * @param ltv The loan to value of the asset when used as collateral
   * @param liquidationThreshold The threshold at which loans using this asset as collateral will be considered undercollateralized
   * @param liquidationBonus The bonus liquidators receive to liquidate this asset. The values is always above 100%. A value of 105%
   * means the liquidator will receive a 5% bonus
   **/
  function configureReserveAsCollateral(
    address asset,
    uint256 ltv,
    uint256 liquidationThreshold,
    uint256 liquidationBonus
  ) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    //validation of the parameters: the LTV can
    //only be lower or equal than the liquidation threshold
    //(otherwise a loan against the asset would cause instantaneous liquidation)
    require(ltv <= liquidationThreshold, Errors.LPC_INVALID_CONFIGURATION);

    if (liquidationThreshold != 0) {
      //liquidation bonus must be bigger than 100.00%, otherwise the liquidator would receive less
      //collateral than needed to cover the debt
      require(
        liquidationBonus > PercentageMath.PERCENTAGE_FACTOR,
        Errors.LPC_INVALID_CONFIGURATION
      );

      //if threshold * bonus is less than PERCENTAGE_FACTOR, it's guaranteed that at the moment
      //a loan is taken there is enough collateral available to cover the liquidation bonus
      require(
        liquidationThreshold.percentMul(liquidationBonus) <= PercentageMath.PERCENTAGE_FACTOR,
        Errors.LPC_INVALID_CONFIGURATION
      );
    } else {
      require(liquidationBonus == 0, Errors.LPC_INVALID_CONFIGURATION);
      //if the liquidation threshold is being set to 0,
      // the reserve is being disabled as collateral. To do so,
      //we need to ensure no liquidity is deposited
      _checkNoLiquidity(asset);
    }

    currentConfig.setLtv(ltv);
    currentConfig.setLiquidationThreshold(liquidationThreshold);
    currentConfig.setLiquidationBonus(liquidationBonus);

    pool.setConfiguration(asset, currentConfig.data);

    emit CollateralConfigurationChanged(asset, ltv, liquidationThreshold, liquidationBonus);
  }

  /**
   * @dev Enable stable rate borrowing on a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  function enableReserveStableRate(address asset) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setStableRateBorrowingEnabled(true);

    pool.setConfiguration(asset, currentConfig.data);

    emit StableRateEnabledOnReserve(asset);
  }

  /**
   * @dev Disable stable rate borrowing on a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  function disableReserveStableRate(address asset) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setStableRateBorrowingEnabled(false);

    pool.setConfiguration(asset, currentConfig.data);

    emit StableRateDisabledOnReserve(asset);
  }

  /**
   * @dev Activates a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  function activateReserve(address asset) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setActive(true);

    pool.setConfiguration(asset, currentConfig.data);

    emit ReserveActivated(asset);
  }

  /**
   * @dev Deactivates a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  function deactivateReserve(address asset) external onlyPoolAdmin {
    _checkNoLiquidity(asset);

    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setActive(false);

    pool.setConfiguration(asset, currentConfig.data);

    emit ReserveDeactivated(asset);
  }

  /**
   * @dev Freezes a reserve. A frozen reserve doesn't allow any new deposit, borrow or rate swap
   *  but allows repayments, liquidations, rate rebalances and withdrawals
   * @param asset The address of the underlying asset of the reserve
   **/
  function freezeReserve(address asset) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setFrozen(true);

    pool.setConfiguration(asset, currentConfig.data);

    emit ReserveFrozen(asset);
  }

  /**
   * @dev Unfreezes a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  function unfreezeReserve(address asset) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setFrozen(false);

    pool.setConfiguration(asset, currentConfig.data);

    emit ReserveUnfrozen(asset);
  }

  /**
   * @dev Updates the reserve factor of a reserve
   * @param asset The address of the underlying asset of the reserve
   * @param reserveFactor The new reserve factor of the reserve
   **/
  function setReserveFactor(address asset, uint256 reserveFactor) external onlyPoolAdmin {
    DataTypes.ReserveConfigurationMap memory currentConfig = pool.getConfiguration(asset);

    currentConfig.setReserveFactor(reserveFactor);

    pool.setConfiguration(asset, currentConfig.data);

    emit ReserveFactorChanged(asset, reserveFactor);
  }

  /**
   * @dev Sets the interest rate strategy of a reserve
   * @param asset The address of the underlying asset of the reserve
   * @param rateStrategyAddress The new address of the interest strategy contract
   **/
  function setReserveInterestRateStrategyAddress(address asset, address rateStrategyAddress)
    external
    onlyPoolAdmin
  {
    pool.setReserveInterestRateStrategyAddress(asset, rateStrategyAddress);
    emit ReserveInterestRateStrategyChanged(asset, rateStrategyAddress);
  }

  /**
   * @dev pauses or unpauses all the actions of the protocol, including aToken transfers
   * @param val true if protocol needs to be paused, false otherwise
   **/
  function setPoolPause(bool val) external onlyEmergencyAdmin {
    pool.setPause(val);
  }

  function _initTokenWithProxy(address implementation, bytes memory initParams)
    internal
    returns (address)
  {
    InitializableImmutableAdminUpgradeabilityProxy proxy =
      new InitializableImmutableAdminUpgradeabilityProxy(address(this));

    proxy.initialize(implementation, initParams);

    return address(proxy);
  }

  function _upgradeTokenImplementation(
    address proxyAddress,
    address implementation,
    bytes memory initParams
  ) internal {
    InitializableImmutableAdminUpgradeabilityProxy proxy =
      InitializableImmutableAdminUpgradeabilityProxy(payable(proxyAddress));

    proxy.upgradeToAndCall(implementation, initParams);
  }

  function _checkNoLiquidity(address asset) internal view {
    DataTypes.ReserveData memory reserveData = pool.getReserveData(asset);

    uint256 availableLiquidity = IERC20Detailed(asset).balanceOf(reserveData.aTokenAddress);

    require(
      availableLiquidity == 0 && reserveData.currentLiquidityRate == 0,
      Errors.LPC_RESERVE_LIQUIDITY_NOT_0
    );
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import './BaseImmutableAdminUpgradeabilityProxy.sol';
import '../../../dependencies/openzeppelin/upgradeability/InitializableUpgradeabilityProxy.sol';

/**
 * @title InitializableAdminUpgradeabilityProxy
 * @dev Extends BaseAdminUpgradeabilityProxy with an initializer function
 */
contract InitializableImmutableAdminUpgradeabilityProxy is
  BaseImmutableAdminUpgradeabilityProxy,
  InitializableUpgradeabilityProxy
{
  constructor(address admin) public BaseImmutableAdminUpgradeabilityProxy(admin) {}

  /**
   * @dev Only fall back when the sender is not the admin.
   */
  function _willFallback() internal override(BaseImmutableAdminUpgradeabilityProxy, Proxy) {
    BaseImmutableAdminUpgradeabilityProxy._willFallback();
  }
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

interface ILendingPoolConfigurator {
  struct InitReserveInput {
    address aTokenImpl;
    address stableDebtTokenImpl;
    address variableDebtTokenImpl;
    uint8 underlyingAssetDecimals;
    address interestRateStrategyAddress;
    address underlyingAsset;
    address treasury;
    address incentivesController;
    string underlyingAssetName;
    string aTokenName;
    string aTokenSymbol;
    string variableDebtTokenName;
    string variableDebtTokenSymbol;
    string stableDebtTokenName;
    string stableDebtTokenSymbol;
    bytes params;
  }

  struct UpdateATokenInput {
    address asset;
    address treasury;
    address incentivesController;
    string name;
    string symbol;
    address implementation;
    bytes params;
  }

  struct UpdateDebtTokenInput {
    address asset;
    address incentivesController;
    string name;
    string symbol;
    address implementation;
    bytes params;
  }

  /**
   * @dev Emitted when a reserve is initialized.
   * @param asset The address of the underlying asset of the reserve
   * @param aToken The address of the associated aToken contract
   * @param stableDebtToken The address of the associated stable rate debt token
   * @param variableDebtToken The address of the associated variable rate debt token
   * @param interestRateStrategyAddress The address of the interest rate strategy for the reserve
   **/
  event ReserveInitialized(
    address indexed asset,
    address indexed aToken,
    address stableDebtToken,
    address variableDebtToken,
    address interestRateStrategyAddress
  );

  /**
   * @dev Emitted when borrowing is enabled on a reserve
   * @param asset The address of the underlying asset of the reserve
   * @param stableRateEnabled True if stable rate borrowing is enabled, false otherwise
   **/
  event BorrowingEnabledOnReserve(address indexed asset, bool stableRateEnabled);

  /**
   * @dev Emitted when borrowing is disabled on a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  event BorrowingDisabledOnReserve(address indexed asset);

  /**
   * @dev Emitted when the collateralization risk parameters for the specified asset are updated.
   * @param asset The address of the underlying asset of the reserve
   * @param ltv The loan to value of the asset when used as collateral
   * @param liquidationThreshold The threshold at which loans using this asset as collateral will be considered undercollateralized
   * @param liquidationBonus The bonus liquidators receive to liquidate this asset
   **/
  event CollateralConfigurationChanged(
    address indexed asset,
    uint256 ltv,
    uint256 liquidationThreshold,
    uint256 liquidationBonus
  );

  /**
   * @dev Emitted when stable rate borrowing is enabled on a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  event StableRateEnabledOnReserve(address indexed asset);

  /**
   * @dev Emitted when stable rate borrowing is disabled on a reserve
   * @param asset The address of the underlying asset of the reserve
   **/
  event StableRateDisabledOnReserve(address indexed asset);

  /**
   * @dev Emitted when a reserve is activated
   * @param asset The address of the underlying asset of the reserve
   **/
  event ReserveActivated(address indexed asset);

  /**
   * @dev Emitted when a reserve is deactivated
   * @param asset The address of the underlying asset of the reserve
   **/
  event ReserveDeactivated(address indexed asset);

  /**
   * @dev Emitted when a reserve is frozen
   * @param asset The address of the underlying asset of the reserve
   **/
  event ReserveFrozen(address indexed asset);

  /**
   * @dev Emitted when a reserve is unfrozen
   * @param asset The address of the underlying asset of the reserve
   **/
  event ReserveUnfrozen(address indexed asset);

  /**
   * @dev Emitted when a reserve factor is updated
   * @param asset The address of the underlying asset of the reserve
   * @param factor The new reserve factor
   **/
  event ReserveFactorChanged(address indexed asset, uint256 factor);

  /**
   * @dev Emitted when the reserve decimals are updated
   * @param asset The address of the underlying asset of the reserve
   * @param decimals The new decimals
   **/
  event ReserveDecimalsChanged(address indexed asset, uint256 decimals);

  /**
   * @dev Emitted when a reserve interest strategy contract is updated
   * @param asset The address of the underlying asset of the reserve
   * @param strategy The new address of the interest strategy contract
   **/
  event ReserveInterestRateStrategyChanged(address indexed asset, address strategy);

  /**
   * @dev Emitted when an aToken implementation is upgraded
   * @param asset The address of the underlying asset of the reserve
   * @param proxy The aToken proxy address
   * @param implementation The new aToken implementation
   **/
  event ATokenUpgraded(
    address indexed asset,
    address indexed proxy,
    address indexed implementation
  );

  /**
   * @dev Emitted when the implementation of a stable debt token is upgraded
   * @param asset The address of the underlying asset of the reserve
   * @param proxy The stable debt token proxy address
   * @param implementation The new aToken implementation
   **/
  event StableDebtTokenUpgraded(
    address indexed asset,
    address indexed proxy,
    address indexed implementation
  );

  /**
   * @dev Emitted when the implementation of a variable debt token is upgraded
   * @param asset The address of the underlying asset of the reserve
   * @param proxy The variable debt token proxy address
   * @param implementation The new aToken implementation
   **/
  event VariableDebtTokenUpgraded(
    address indexed asset,
    address indexed proxy,
    address indexed implementation
  );
}

// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.12;

import '../../../dependencies/openzeppelin/upgradeability/BaseUpgradeabilityProxy.sol';

/**
 * @title BaseImmutableAdminUpgradeabilityProxy
 * @author Aave, inspired by the OpenZeppelin upgradeability proxy pattern
 * @dev This contract combines an upgradeability proxy with an authorization
 * mechanism for administrative tasks. The admin role is stored in an immutable, which
 * helps saving transactions costs
 * All external functions in this contract must be guarded by the
 * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
 * feature proposal that would enable this to be done automatically.
 */
contract BaseImmutableAdminUpgradeabilityProxy is BaseUpgradeabilityProxy {
  address immutable ADMIN;

  constructor(address admin) public {
    ADMIN = admin;
  }

  modifier ifAdmin() {
    if (msg.sender == ADMIN) {
      _;
    } else {
      _fallback();
    }
  }

  /**
   * @return The address of the proxy admin.
   */
  function admin() external ifAdmin returns (address) {
    return ADMIN;
  }

  /**
   * @return The address of the implementation.
   */
  function implementation() external ifAdmin returns (address) {
    return _implementation();
  }

  /**
   * @dev Upgrade the backing implementation of the proxy.
   * Only the admin can call this function.
   * @param newImplementation Address of the new implementation.
   */
  function upgradeTo(address newImplementation) external ifAdmin {
    _upgradeTo(newImplementation);
  }

  /**
   * @dev Upgrade the backing implementation of the proxy and call a function
   * on the new implementation.
   * This is useful to initialize the proxied contract.
   * @param newImplementation Address of the new implementation.
   * @param data Data to send as msg.data in the low level call.
   * It should include the signature and the parameters of the function to be called, as described in
   * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
   */
  function upgradeToAndCall(address newImplementation, bytes calldata data)
    external
    payable
    ifAdmin
  {
    _upgradeTo(newImplementation);
    (bool success, ) = newImplementation.delegatecall(data);
    require(success);
  }

  /**
   * @dev Only fall back when the sender is not the admin.
   */
  function _willFallback() internal virtual override {
    require(msg.sender != ADMIN, 'Cannot call fallback function from the proxy admin');
    super._willFallback();
  }
}

// S