drop/server/api/v1/notifications/ws.get.ts

import notificationSystem from "~/server/internal/notifications";
import session from "~/server/internal/session";
import { parse as parseCookies } from "cookie-es";

// TODO add web socket sessions for horizontal scaling
// Peer ID to user ID
const socketSessions: { [key: string]: string } = {};

export default defineWebSocketHandler({
  async open(peer) {
    const cookies = peer.request?.headers?.get("Cookie");
    if (!cookies) {
      peer.send("unauthenticated");
      return;
    }

    const parsedCookies = parseCookies(cookies);
    const token = parsedCookies[session.getDropTokenCookie()];

    const userId = await session.getUserIdRaw(token);
    if (!userId) {
      peer.send("unauthenticated");
      return;
    }

    socketSessions[peer.id] = userId;

    notificationSystem.listen(userId, peer.id, (notification) => {
      peer.send(JSON.stringify(notification));
    });
  },
  async close(peer, details) {
    const userId = socketSessions[peer.id];
    if (!userId) {
      console.log(`skipping websocket close for ${peer.id}`);
      return;
    }

    notificationSystem.unlisten(userId, peer.id);
    delete socketSessions[peer.id];
  },
});