/*
    Copyright 2021 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { ILendingPool } from "../../../interfaces/external/aave-v2/ILendingPool.sol";
import { ISetToken } from "../../../interfaces/ISetToken.sol";

/**
 * @title AaveV2
 * @author Set Protocol
 * 
 * Collection of helper functions for interacting with AaveV2 integrations.
 */
library AaveV2 {
    /* ============ External ============ */
    
    /**
     * Get deposit calldata from SetToken
     *
     * Deposits an `_amountNotional` of underlying asset into the reserve, receiving in return overlying aTokens.
     * - E.g. User deposits 100 USDC and gets in return 100 aUSDC
     * @param _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the underlying asset to deposit
     * @param _amountNotional       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
     *
     * @return address              Target contract address
     * @return uint256              Call value
     * @return bytes                Deposit calldata
     */
    function getDepositCalldata(
        ILendingPool _lendingPool,
        address _asset, 
        uint256 _amountNotional,
        address _onBehalfOf,
        uint16 _referralCode
    )
        public
        pure
        returns (address, uint256, bytes memory)
    {
        bytes memory callData = abi.encodeWithSignature(
            "deposit(address,uint256,address,uint16)", 
            _asset, 
            _amountNotional, 
            _onBehalfOf,
            _referralCode
        );
        
        return (address(_lendingPool), 0, callData);
    }
    
    /**
     * Invoke deposit on LendingPool from SetToken
     * 
     * Deposits an `_amountNotional` of underlying asset into the reserve, receiving in return overlying aTokens.
     * - E.g. SetToken deposits 100 USDC and gets in return 100 aUSDC
     * @param _setToken             Address of the SetToken
     * @param _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the underlying asset to deposit
     * @param _amountNotional       The amount to be deposited
     */
    function invokeDeposit(
        ISetToken _setToken,
        ILendingPool _lendingPool,
        address _asset,
        uint256 _amountNotional        
    )
        external
    {
        ( , , bytes memory depositCalldata) = getDepositCalldata(
            _lendingPool,
            _asset,
            _amountNotional, 
            address(_setToken), 
            0
        );
        
        _setToken.invoke(address(_lendingPool), 0, depositCalldata);
    }
    
    /**
     * Get withdraw calldata from SetToken
     * 
     * Withdraws an `_amountNotional` 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 _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the underlying asset to withdraw
     * @param _amountNotional       The underlying amount to be withdrawn
     *                              Note: Passing type(uint256).max will withdraw the entire aToken balance
     * @param _receiver             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 address              Target contract address
     * @return uint256              Call value
     * @return bytes                Withdraw calldata
     */
    function getWithdrawCalldata(
        ILendingPool _lendingPool,
        address _asset, 
        uint256 _amountNotional,
        address _receiver        
    )
        public
        pure
        returns (address, uint256, bytes memory)
    {
        bytes memory callData = abi.encodeWithSignature(
            "withdraw(address,uint256,address)", 
            _asset, 
            _amountNotional, 
            _receiver
        );
        
        return (address(_lendingPool), 0, callData);
    }
    
    /**
     * Invoke withdraw on LendingPool from SetToken
     * 
     * Withdraws an `_amountNotional` of underlying asset from the reserve, burning the equivalent aTokens owned
     * - E.g. SetToken has 100 aUSDC, and receives 100 USDC, burning the 100 aUSDC
     *     
     * @param _setToken         Address of the SetToken
     * @param _lendingPool      Address of the LendingPool contract
     * @param _asset            The address of the underlying asset to withdraw
     * @param _amountNotional   The underlying amount to be withdrawn
     *                          Note: Passing type(uint256).max will withdraw the entire aToken balance
     *
     * @return uint256          The final amount withdrawn
     */
    function invokeWithdraw(
        ISetToken _setToken,
        ILendingPool _lendingPool,
        address _asset,
        uint256 _amountNotional        
    )
        external
        returns (uint256)
    {
        ( , , bytes memory withdrawCalldata) = getWithdrawCalldata(
            _lendingPool,
            _asset,
            _amountNotional, 
            address(_setToken)
        );
        
        return abi.decode(_setToken.invoke(address(_lendingPool), 0, withdrawCalldata), (uint256));
    }
    
    /**
     * Get borrow calldata from SetToken
     *
     * Allows users to borrow a specific `_amountNotional` 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)
     *
     * @param _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the underlying asset to borrow
     * @param _amountNotional       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
     *
     * @return address              Target contract address
     * @return uint256              Call value
     * @return bytes                Borrow calldata
     */
    function getBorrowCalldata(
        ILendingPool _lendingPool,
        address _asset, 
        uint256 _amountNotional,
        uint256 _interestRateMode,
        uint16 _referralCode,
        address _onBehalfOf
    )
        public
        pure
        returns (address, uint256, bytes memory)
    {
        bytes memory callData = abi.encodeWithSignature(
            "borrow(address,uint256,uint256,uint16,address)", 
            _asset, 
            _amountNotional, 
            _interestRateMode,
            _referralCode,
            _onBehalfOf
        );
        
        return (address(_lendingPool), 0, callData);
    }
    
    /**
     * Invoke borrow on LendingPool from SetToken
     *
     * Allows SetToken to borrow a specific `_amountNotional` of the reserve underlying `_asset`, provided that 
     * the SetToken already deposited enough collateral, or it was given enough allowance by a credit delegator
     * on the corresponding debt token (StableDebtToken or VariableDebtToken)
     * @param _setToken             Address of the SetToken
     * @param _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the underlying asset to borrow
     * @param _amountNotional       The amount to be borrowed
     * @param _interestRateMode     The interest rate mode at which the user wants to borrow: 1 for Stable, 2 for Variable
     */
    function invokeBorrow(
        ISetToken _setToken,
        ILendingPool _lendingPool,
        address _asset,
        uint256 _amountNotional,
        uint256 _interestRateMode
    )
        external
    {
        ( , , bytes memory borrowCalldata) = getBorrowCalldata(
            _lendingPool,
            _asset,
            _amountNotional,
            _interestRateMode,
            0, 
            address(_setToken)
        );
        
        _setToken.invoke(address(_lendingPool), 0, borrowCalldata);
    }

    /**
     * Get repay calldata from SetToken
     *
     * Repays a borrowed `_amountNotional` on a specific `_asset` reserve, burning the equivalent debt tokens owned
     * - E.g. User repays 100 USDC, burning 100 variable/stable debt tokens of the `onBehalfOf` address
     * @param _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the borrowed underlying asset previously borrowed
     * @param _amountNotional       The amount to repay
     *                              Note: Passing type(uint256).max will repay the whole debt for `_asset` on the specific `_interestRateMode`
     * @param _interestRateMode     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 address              Target contract address
     * @return uint256              Call value
     * @return bytes                Repay calldata
     */
    function getRepayCalldata(
        ILendingPool _lendingPool,
        address _asset, 
        uint256 _amountNotional,
        uint256 _interestRateMode,        
        address _onBehalfOf
    )
        public
        pure
        returns (address, uint256, bytes memory)
    {
        bytes memory callData = abi.encodeWithSignature(
            "repay(address,uint256,uint256,address)", 
            _asset, 
            _amountNotional, 
            _interestRateMode,            
            _onBehalfOf
        );
        
        return (address(_lendingPool), 0, callData);
    }

    /**
     * Invoke repay on LendingPool from SetToken
     *
     * Repays a borrowed `_amountNotional` on a specific `_asset` reserve, burning the equivalent debt tokens owned
     * - E.g. SetToken repays 100 USDC, burning 100 variable/stable debt tokens
     * @param _setToken             Address of the SetToken
     * @param _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the borrowed underlying asset previously borrowed
     * @param _amountNotional       The amount to repay
     *                              Note: Passing type(uint256).max will repay the whole debt for `_asset` on the specific `_interestRateMode`
     * @param _interestRateMode     The interest rate mode at of the debt the user wants to repay: 1 for Stable, 2 for Variable
     *
     * @return uint256              The final amount repaid
     */
    function invokeRepay(
        ISetToken _setToken,
        ILendingPool _lendingPool,
        address _asset,
        uint256 _amountNotional,
        uint256 _interestRateMode
    )
        external
        returns (uint256)
    {
        ( , , bytes memory repayCalldata) = getRepayCalldata(
            _lendingPool,
            _asset,
            _amountNotional,
            _interestRateMode,
            address(_setToken)
        );
        
        return abi.decode(_setToken.invoke(address(_lendingPool), 0, repayCalldata), (uint256));
    }

    /**
     * Get setUserUseReserveAsCollateral calldata from SetToken
     * 
     * Allows borrower to enable/disable a specific deposited asset as collateral
     * @param _lendingPool          Address of the LendingPool contract
     * @param _asset                The address of the underlying asset deposited
     * @param _useAsCollateral      true` if the user wants to use the deposit as collateral, `false` otherwise
     *
     * @return address              Target contract address
     * @return uint256              Call value
     * @return bytes                SetUserUseReserveAsCollateral calldata
     */
    function getSetUserUseReserveAsCollateralCalldata(
        ILendingPool _lendingPool,
        address _asset,
        bool _useAsCollateral
    )
        public
        pure
        returns (address, uint256, bytes memory)
    {
        bytes memory callData = abi.encodeWithSignature(
            "setUserUseReserveAsCollateral(address,bool)", 
            _asset,
            _useAsCollateral
        );
        
        return (address(_lendingPool), 0, callData);
    }

    /**
     * Invoke an asset to be used as collateral on Aave from SetToken
     *
     * Allows SetToken to enable/disable a specific deposited asset as collateral
     * @param _setToken             Address of the SetToken
     * @param _lendingPool          Address of the LendingPool contract
     * @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 invokeSetUserUseReserveAsCollateral(
        ISetToken _setToken,
        ILendingPool _lendingPool,
        address _asset,
        bool _useAsCollateral
    )
        external
    {
        ( , , bytes memory callData) = getSetUserUseReserveAsCollateralCalldata(
            _lendingPool,
            _asset,
            _useAsCollateral
        );
        
        _setToken.invoke(address(_lendingPool), 0, callData);
    }
    
    /**
     * Get swapBorrowRate calldata from SetToken
     *
     * Allows a borrower to toggle his debt between stable and variable mode
     * @param _lendingPool      Address of the LendingPool contract
     * @param _asset            The address of the underlying asset borrowed
     * @param _rateMode         The rate mode that the user wants to swap to
     *
     * @return address          Target contract address
     * @return uint256          Call value
     * @return bytes            SwapBorrowRate calldata
     */
    function getSwapBorrowRateModeCalldata(
        ILendingPool _lendingPool,
        address _asset,
        uint256 _rateMode
    )
        public
        pure
        returns (address, uint256, bytes memory)
    {
        bytes memory callData = abi.encodeWithSignature(
            "swapBorrowRateMode(address,uint256)", 
            _asset,
            _rateMode
        );
        
        return (address(_lendingPool), 0, callData);
    }

    /**
     * Invoke to swap borrow rate of SetToken
     * 
     * Allows SetToken to toggle it's debt between stable and variable mode
     * @param _setToken         Address of the SetToken
     * @param _lendingPool      Address of the LendingPool contract
     * @param _asset            The address of the underlying asset borrowed
     * @param _rateMode         The rate mode that the user wants to swap to
     */
    function invokeSwapBorrowRateMode(
        ISetToken _setToken,
        ILendingPool _lendingPool,
        address _asset,
        uint256 _rateMode
    )
        external
    {
        ( , , bytes memory callData) = getSwapBorrowRateModeCalldata(
            _lendingPool,
            _asset,
            _rateMode
        );
        
        _setToken.invoke(address(_lendingPool), 0, callData);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

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

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

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

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

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

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

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

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

/*
  Copyright 2021 Set Labs Inc.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

  SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;
pragma experimental ABIEncoderV2;

import { ILendingPoolAddressesProvider } from "./ILendingPoolAddressesProvider.sol";
import { DataTypes } from "./lib/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);
}

/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;
pragma experimental "ABIEncoderV2";

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";

/**
 * @title ISetToken
 * @author Set Protocol
 *
 * Interface for operating with SetTokens.
 */
interface ISetToken is IERC20 {

    /* ============ Enums ============ */

    enum ModuleState {
        NONE,
        PENDING,
        INITIALIZED
    }

    /* ============ Structs ============ */
    /**
     * The base definition of a SetToken Position
     *
     * @param component           Address of token in the Position
     * @param module              If not in default state, the address of associated module
     * @param unit                Each unit is the # of components per 10^18 of a SetToken
     * @param positionState       Position ENUM. Default is 0; External is 1
     * @param data                Arbitrary data
     */
    struct Position {
        address component;
        address module;
        int256 unit;
        uint8 positionState;
        bytes data;
    }

    /**
     * A struct that stores a component's cash position details and external positions
     * This data structure allows O(1) access to a component's cash position units and 
     * virtual units.
     *
     * @param virtualUnit               Virtual value of a component's DEFAULT position. Stored as virtual for efficiency
     *                                  updating all units at once via the position multiplier. Virtual units are achieved
     *                                  by dividing a "real" value by the "positionMultiplier"
     * @param componentIndex            
     * @param externalPositionModules   List of external modules attached to each external position. Each module
     *                                  maps to an external position
     * @param externalPositions         Mapping of module => ExternalPosition struct for a given component
     */
    struct ComponentPosition {
      int256 virtualUnit;
      address[] externalPositionModules;
      mapping(address => ExternalPosition) externalPositions;
    }

    /**
     * A struct that stores a component's external position details including virtual unit and any
     * auxiliary data.
     *
     * @param virtualUnit       Virtual value of a component's EXTERNAL position.
     * @param data              Arbitrary data
     */
    struct ExternalPosition {
      int256 virtualUnit;
      bytes data;
    }


    /* ============ Functions ============ */
    
    function addComponent(address _component) external;
    function removeComponent(address _component) external;
    function editDefaultPositionUnit(address _component, int256 _realUnit) external;
    function addExternalPositionModule(address _component, address _positionModule) external;
    function removeExternalPositionModule(address _component, address _positionModule) external;
    function editExternalPositionUnit(address _component, address _positionModule, int256 _realUnit) external;
    function editExternalPositionData(address _component, address _positionModule, bytes calldata _data) external;

    function invoke(address _target, uint256 _value, bytes calldata _data) external returns(bytes memory);

    function editPositionMultiplier(int256 _newMultiplier) external;

    function mint(address _account, uint256 _quantity) external;
    function burn(address _account, uint256 _quantity) external;

    function lock() external;
    function unlock() external;

    function addModule(address _module) external;
    function removeModule(address _module) external;
    function initializeModule() external;

    function setManager(address _manager) external;

    function manager() external view returns (address);
    function moduleStates(address _module) external view returns (ModuleState);
    function getModules() external view returns (address[] memory);
    
    function getDefaultPositionRealUnit(address _component) external view returns(int256);
    function getExternalPositionRealUnit(address _component, address _positionModule) external view returns(int256);
    function getComponents() external view returns(address[] memory);
    function getExternalPositionModules(address _component) external view returns(address[] memory);
    function getExternalPositionData(address _component, address _positionModule) external view returns(bytes memory);
    function isExternalPositionModule(address _component, address _module) external view returns(bool);
    function isComponent(address _component) external view returns(bool);
    
    function positionMultiplier() external view returns (int256);
    function getPositions() external view returns (Position[] memory);
    function getTotalComponentRealUnits(address _component) external view returns(int256);

    function isInitializedModule(address _module) external view returns(bool);
    function isPendingModule(address _module) external view returns(bool);
    function isLocked() external view returns (bool);
}

/*
  Copyright 2021 Set Labs Inc.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

  SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;

/**
 * @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;
}

/*
  Copyright 2021 Set Labs Inc.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

  SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;

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}
}