protohackers/6.ts

import { BufReader } from "https://deno.land/std@0.157.0/io/buffer.ts";

const PORT = 5588;

// const tEnc = new TextEncoder();

console.log(`Starting TCP listener on on 0.0.0.0:${PORT}`);

function chatSession(conn: Deno.Conn) {
  const closeOnDisconnect = () => {
    console.warn("Disconnected client");
    try {
      conn.close();
    } catch (err) {
      console.error("Error closing client connection:", err);
    }
  };

  serve(conn).catch((e) => e).finally(closeOnDisconnect);
}

async function serve(conn: Deno.Conn) {
  const reader = new BufReader(conn);
  const type = await reader.peek(1);
  if (!type) throw new Error("failed to peek start of packet");
  console.log(type);
}

for await (const conn of Deno.listen({ port: PORT })) {
  console.log("Connection established:", conn.remoteAddr);
  chatSession(conn);
  console.log("Connection closed:", conn.remoteAddr);
}