FlashLoanArbitrage.sol

pragma solidity ^0.6.0;

import './Libraries/SafeMath.sol';
import './Interfaces/IPancakeERC20.sol';
import './Interfaces/IPancakeFactory.sol';
import './Interfaces/IPancakePair.sol';
import './Interfaces/IPancakeRouter01.sol';
import './Libraries/PancakeLibrary.sol';
import './Interfaces/IBakerySwapRouter.sol';

contract TestFlashLoan{
    address owner;
    
    //token
    address wbnbAddr;
    address busdAddr;
    
    //Pancake
    address wbnb_busd_pancakeLPAddr;
    address pancakeRouterAddr;
    address pancakeFactoryAddr;
    IPancakeRouter01 pancakeRouter;
    
    //Bakery
    address wbnb_busd_bakeryLPAddr;
    address bakeryRouterAddr;
    address bakeryFactoryAddr;
    
    event Log(uint amout);
    
    constructor() public {
        //me
        owner = msg.sender;
        
        //Bakery
        //wbnb_busd_bakeryLPAddr = ;
        bakeryRouterAddr = 0xCDe540d7eAFE93aC5fE6233Bee57E1270D3E330F;
        bakeryFactoryAddr = 0x01bF7C66c6BD861915CdaaE475042d3c4BaE16A7;
        
        //Pancake
        wbnb_busd_pancakeLPAddr = 0x0126D4Bbb6f6059128869E49B25F6dA9121D8C75;
        pancakeRouterAddr = 0x9Ac64Cc6e4415144C455BD8E4837Fea55603e5c3;
        pancakeFactoryAddr = 0xB7926C0430Afb07AA7DEfDE6DA862aE0Bde767bc;
        
        //token
        busdAddr = 0xCb096FA97d970ac01857cB76186e228262dE2999;
        wbnbAddr = 0xbA4756Ef6f19E75EAfF9e20Ed69d913C7eec4176;
    }
    
    // flash swap for busd, busd is amount1, wbnb is amount0
    function pancakeFlashLoan(
        uint amount0,
        uint amount1
    ) external {
        IPancakePair(wbnb_busd_pancakeLPAddr).swap(
            amount0,
            amount1,
            address(this),
            bytes("something")
        );
    }
    
    function pancakeCall(
        address _sender,
        uint _amount0,
        uint _amount1,
        bytes calldata _data
    ) external {
        uint amountToken = _amount0 == 0 ? _amount1 : _amount0;
        address[] memory path = new address[](2);
        path[0] = busdAddr;
        path[1] = wbnbAddr;
        
        uint amountOutMin = IBakerySwapRouter(bakeryRouterAddr).getAmountsOut(
            amountToken,
            path
        )[1];
        uint deadline = now + 20 minutes;
        IPancakeERC20 busd = IPancakeERC20(busdAddr);
        busd.approve(address(bakeryRouterAddr), amountToken);
        uint amountReceived = IBakerySwapRouter(bakeryRouterAddr).swapExactTokensForTokens(
            amountToken,
            amountOutMin,
            path,
            address(this),
            deadline
        )[1];
        
        address[] memory pathRepay = new address[](2);
        pathRepay[0] = wbnbAddr; //y
        pathRepay[1] = busdAddr; //x
        uint amountRepay = PancakeLibrary.getAmountsIn(
            pancakeFactoryAddr,
            amountToken,
            pathRepay
        )[0];
        
        IPancakeERC20 otherToken = IPancakeERC20(wbnbAddr);
        otherToken.transfer(wbnb_busd_pancakeLPAddr, amountRepay);
        
        uint profit = IPancakeERC20(wbnbAddr).balanceOf(address(this));
        otherToken.transfer(owner, profit);
    }
    
}