server.js

import express from "express";
import "dotenv/config";
import cors from "cors";
import http from "http";
import { connectDB } from "./lib/db.js";
import userRouter from "./routes/userRoutes.js";
import messageRouter from "./routes/messageRoutes.js";
import { Server } from "socket.io";

const port = process.env.PORT || 10000;

const app = express();
const server = http.createServer(app);

// initialize socket.io server
export const io = new Server(server, { cors: { origin: "*" } });
// store online users
export const userSocketMap = {}; // {userId: socketId}

// socket.io connection handler
io.on("connection", (socket) => {
	const userId = socket.handshake.query.userId;
	console.log("User connected", userId);

	if (userId) userSocketMap[userId] = socket.id;

	// emit online users to all connected clients
	io.emit("getOnlineUsers", Object.keys(userSocketMap));

	socket.on("disconnect", () => {
		console.log("User Disconnected", userId);
		delete userSocketMap[userId];
		io.emit("getOnlineUsers", Object.keys(userSocketMap));
	});
});

//middlewares
app.use(express.json({ limit: "4mb" }));
app.use(cors());

app.use("/api/status", (req, res) => {
	res.send("Server is live");
});
app.use("/api/auth", userRouter);
app.use("/api/messages", messageRouter);

await connectDB();


if (process.env.NODE_ENV !== "production") {
	server.listen(port, () => console.log("Server is running on PORT: " + port));
}

// export server for vercel
export default server