dydx flash loan almost done

contracts/connectors/dydxFlash.sol

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+pragma solidity ^0.6.0;
+
+import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
+import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+
+// import files from common directory
+import { TokenInterface , MemoryInterface, EventInterface} from "../common/interfaces.sol";
+import { Stores } from "../common/stores.sol";
+import { DSMath } from "../common/math.sol";
+
+
+/**
+ * @title ConnectBasic.
+ * @dev Connector to deposit/withdraw assets.
+ */
+
+interface AccountInterface {
+    function enable(address) external;
+    function disable(address) external;
+}
+
+interface DydxFlashInterface {
+    function initiateFlashLoan(address _token, uint256 _amount, bytes calldata data) external;
+}
+
+contract BasicResolver is Stores {
+
+    using SafeERC20 for IERC20;
+
+    /**
+        * @dev Return ethereum address
+    */
+    function getDydxLoanAddr() internal pure returns (address) {
+        return address(0); // check9898 - change to dydx flash contract address
+    }
+
+    function getWethAddr() internal pure returns (address) {
+        return 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
+    }
+
+    /**
+     * @dev Deposit Assets To Smart Account.
+     * @param token Token Address.
+     * @param tokenAmt Token Amount.
+     * @param data targets & data for cast.
+     */
+    function borrowAndCast(address token, uint tokenAmt, bytes memory data) public payable {
+        AccountInterface(address(this)).enable(getDydxLoanAddr());
+
+        address _token = token == getEthAddr() ? getWethAddr() : token;
+
+        DydxFlashInterface(getDydxLoanAddr()).initiateFlashLoan(_token, tokenAmt, data);
+
+        if (token == getEthAddr()) {
+            payable(getDydxLoanAddr()).transfer(tokenAmt);
+        } else {
+            IERC20(token).transfer(getDydxLoanAddr(), tokenAmt);
+        }
+
+        AccountInterface(address(this)).disable(getDydxLoanAddr());
+    }
+
+}
+
+
+contract ConnectBasic is BasicResolver {
+    string public constant name = "dydx-flashloan-v1";
+}

contracts/flashloan/dydx.sol

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+pragma solidity ^0.6.0;
+pragma experimental ABIEncoderV2;
+
+import "@studydefi/money-legos/dydx/contracts/DydxFlashloanBase.sol";
+import "@studydefi/money-legos/dydx/contracts/ICallee.sol";
+
+import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+
+interface DSAInterface {
+    function cast(address[] calldata _targets, bytes[] calldata _datas, address _origin) external payable;
+}
+
+contract DydxFlashloaner is ICallee, DydxFlashloanBase {
+
+    address public constant soloAddr = 0x1E0447b19BB6EcFdAe1e4AE1694b0C3659614e4e;
+
+    struct CastData {
+        address[] targets;
+        bytes[] data;
+    }
+
+    // check9898 - add block re-entrance
+    function callFunction(
+        address sender,
+        Account.Info memory account,
+        bytes memory data
+    ) public {
+        CastData memory cd = abi.decode(data, (CastData));
+
+        // check9898 - change to DSA address & origin address too
+        DSAInterface(address(0)).cast(cd.targets, cd.data, address(0));
+    }
+
+    // check9898 - if ETH then change 0xeeeee into WETH address and change the token into ETH before sending
+    function initiateFlashLoan(address _token, uint256 _amount, bytes calldata data)
+        external
+    {
+        ISoloMargin solo = ISoloMargin(soloAddr);
+
+        // Get marketId from token address
+        uint256 marketId = _getMarketIdFromTokenAddress(soloAddr, _token);
+
+        IERC20(_token).approve(soloAddr, _amount + 2);
+
+        Actions.ActionArgs[] memory operations = new Actions.ActionArgs[](3);
+
+        operations[0] = _getWithdrawAction(marketId, _amount);
+        operations[1] = _getCallAction(data);
+        operations[2] = _getDepositAction(marketId, repayAmount);
+
+        Account.Info[] memory accountInfos = new Account.Info[](1);
+        accountInfos[0] = _getAccountInfo();
+
+        IERC20 _tokenContract = IERC20(_token);
+        uint iniBal = _tokenContract.balanceOf(address(this));
+
+        solo.operate(accountInfos, operations);
+
+        uint finBal = _tokenContract.balanceOf(address(this));
+        require(sub(iniBal, finBal) < 10, "amount-paid-less");
+    }
+}