Short SUSD with USDC

shortsusd.js

const Web3 = require('web3');
const DSA = require('dsa-sdk');

const ETH_ADDRESS = 'XXXX';
const ADDRESS_PVT_KEY = 'XXXX'
const TARGET_ENDPOINT = 'https://mainnet.infura.io/v3/XXXX';
const mainnetP = new Web3.providers.HttpProvider(TARGET_ENDPOINT);
const web3 = new Web3(mainnetP);

const dsa = new DSA({
  web3,
  mode: 'node',
  privateKey: ADDRESS_PVT_KEY,
});

dsa
	.getAccounts(ETH_ADDRESS)
	.then(async ([ dsaAccount ]) => {
		// console.log(dsaAccount);
		dsa.setInstance(dsaAccount.id);

		// DSA related
		const spells = dsa.Spell();
		const { dai, usdc, susd } = dsa.tokens.info;
		const [ notBeingUsed, { address: USDC }, { address: SUSD } ] = [ dai, usdc, susd ];
		// console.log(notBeingUsed, USDC, SUSD);

		// Static values
		const personalAmountInWallet = 100;
		const amountFlashBorrowed = 300;
		const combinedAmountInWallet = personalAmountInWallet + amountFlashBorrowed;
		const slippageAllowed = 0.5;
		const zeroValue = 0;
		const maxValue = -1;

		// FIND OUT HOW MUCH USDC you need to borrow,
		// by checking swap rate between SUSD and USDC
		// You want to BORROW the PROFITS you would have made by BORROWING SUSD & SWAPING it for USDC
		const swappedSUSDforUSDC = await dsa.curve_susd.getBuyAmount(
			...[ 'USDC', 'SUSD', combinedAmountInWallet, slippageAllowed ]
		);

		// 1. BORROW x3 of the amount you have in your wallet
		// Note: BORROW DAI due to lower slippage when swapping with SUSD
		let amountFlashBorrowedInWei = dsa.tokens.fromDecimal(swappedSUSDforUSDC.buyAmt, 'usdc');
		spells.add({
			connector: 'instapool',
			method: 'flashBorrow',
			args: [ USDC, amountFlashBorrowedInWei, zeroValue, zeroValue ]
		});

		// 5. Payback the borrowed amount
		spells.add({
			connector: 'instapool',
			method: 'flashPayback',
			args: [ USDC, zeroValue, zeroValue ]
		});

		// const results = await dsa.cast({ spells });
		// console.info(0, results);

		const BN = web3.utils.BN;
		const gas = 1.5e6; // web3.utils.toBN(gasLimit);
		const currentGasPrice = await web3.eth.getGasPrice();
		const gasPrice = web3.utils.toWei(web3.utils.toBN(100), 'gwei');
		// console.log('GAS PRICE', currentGasPrice, gasPrice);

		const gasAndGasPrice = {
			gasPrice: currentGasPrice.toString(),
			gas: gas.toString()
		};

		let spellsEncoded = dsa.internal.encodeSpells({
			spells,
			...gasAndGasPrice
		});

		const to = dsaAccount.address;
		const from = ETH_ADDRESS;
		const origin = dsa.origin;

		const contract = new dsa.web3.eth.Contract(dsa.ABI.core.account, dsaAccount.address);

		const callData = contract.methods.cast(...spellsEncoded, origin).encodeABI();
		console.log(
			await dsa.internal.getTxObj({
				spells,
				to,
				from,
				origin,
				callData,
				...gasAndGasPrice
			})
		);
	})
	.catch(console.log);