gistfile1.txt

import { JsonRpcProvider } from "@ethersproject/providers";
import { CurrencyAmount, Percent, Token, TradeType } from "@uniswap/sdk-core";
import {
  AlphaRouter,
  SwapOptionsUniversalRouter,
  SwapType,
} from "@uniswap/smart-order-router";
import { UniversalRouterVersion } from "@uniswap/universal-router-sdk";
const provider = new JsonRpcProvider(
  "https://polygon-mainnet.g.alchemy.com/v2/<KEY>"
);

const runRoute = async () => {
  const tokenIn = new Token(
    Number(137),
    "0xE6A537a407488807F0bbeb0038B79004f19DDDFb",
    18,
    "BRLA",
    "BRLA"
  );

  const tokenOut = new Token(
    Number(137),
    "0xc2132D05D31c914a87C6611C10748AEb04B58e8F",
    6,
    "USDT",
    "USDT"
  );

  const router = new AlphaRouter({
    chainId: 137,
    provider,
  });

  console.time("Route time");
  const routeOptions: SwapOptionsUniversalRouter = {
    recipient: "0x24c09364c62E695dbAbd7bBDB8fa65e485cF9E91",
    slippageTolerance: new Percent(0.5 * 100, 10_000), // eg. 0.5
    type: SwapType.UNIVERSAL_ROUTER,
    version: UniversalRouterVersion.V2_0,
  };

  const amount = 1713.19;

  const amountOutBigint = BigInt(amount * 10 ** 6).toString();
  const amountOut = CurrencyAmount.fromRawAmount(
    tokenOut,
    amountOutBigint.toString()
  );

  let route = await router.route(
    amountOut,
    tokenIn,
    TradeType.EXACT_OUTPUT,
    routeOptions
  );

  const quote = route?.trade
    ?.maximumAmountIn(routeOptions.slippageTolerance)
    .quotient.toString();

  console.info("Swap Quote", {
    amountOut: Number(amountOutBigint.toString()) / 10 ** 6,
    quoteIn: Number(route.quote.quotient.toString()) / 10 ** 18,
  });

  console.timeEnd("Route time");
};

runRoute();