Receiving Messages

const handlers = { "chat.message": onChat, "presence": onPresence };
ws.addEventListener("message", (e) => {
  const msg = JSON.parse(e.data);
  handlers[msg.type]?.(msg.payload);
});

function safeParse(raw) {
  try { return JSON.parse(raw); }
  catch { return null; }
}

import { z } from "zod";
const ChatMsg = z.object({ "type": z.literal("chat.message"), "text": z.string().max(2000) });
const result = ChatMsg.safeParse(parsed);
if (!result.success) return reject(result.error);

ws.binaryType = "arraybuffer";
ws.addEventListener("message", (e) => {
  if (typeof e.data === "string") handleText(e.data);
  else if (e.data instanceof ArrayBuffer) handleBinary(new DataView(e.data));
});

ws.addEventListener("message", async (e) => {
  if (e.data instanceof Blob) {
    const buf = await e.data.arrayBuffer();
    processBinary(buf);
  }
});

function decode(view) {
  const type = view.getUint8(0);
  const len  = view.getUint32(1, false); // big-endian
  const body = new Uint8Array(view.buffer, 5, len);
  return { type, body };
}

function makeQueue(ws) {
  const buf = [], waiters = [];
  ws.addEventListener("message", (e) => {
    if (waiters.length) waiters.shift()(e.data);
    else buf.push(e.data);
  });
  return {
    async next() {
      if (buf.length) return buf.shift();
      return new Promise(res => waiters.push(res));
    }
  };
}