app.js

import express from "express";
import { Server as SocketServer } from "socket.io";
import { inject } from "@vercel/analytics";

import http from "http";
import { Chess } from "chess.js";
import path from "path";
import { fileURLToPath } from "url";
import { injectSpeedInsights } from "@vercel/speed-insights";

injectSpeedInsights();
inject();
const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const app = express();
const server = http.createServer(app);
const io = new SocketServer(server);

const chess = new Chess();
let players = {};

app.set("view engine", "ejs");
app.set("views", path.join(__dirname, "views"));

app.use(express.static(path.join(__dirname, "public")));

app.get("/", (req, res) => {
	res.render("index", { title: "Chess Game" });
});

io.on("connection", (uniquesocket) => {
	console.log("connected");
	if (!players.white) {
		players.white = uniquesocket.id;
		uniquesocket.emit("playerRole", "w");
	} else if (!players.black) {
		players.black = uniquesocket.id;
		uniquesocket.emit("playerRole", "b");
	} else {
		uniquesocket.emit("spectatorRole");
	}
	uniquesocket.on("disconnect", () => {
		if (uniquesocket.id === players.white) {
			delete players.white;
		} else if (uniquesocket.id === players.black) {
			delete players.black;
		}
	});
	uniquesocket.on("move", (move) => {
		try {
			if (chess.turn() === "w" && uniquesocket.id !== players.white) return;
			if (chess.turn() === "b" && uniquesocket.id !== players.black) return;
			const result = chess.move(move);

			if (result) {
				io.emit("move", move);
				io.emit("boardState", chess.fen());
			} else {
				console.log("Invalid move:", move);
				uniquesocket.emit("invalidMove", move);
			}
		} catch (err) {
			console.log(err);
			uniquesocket.emit("invalidMove", move);
		}
	});
});

app.use((err, req, res, next) => {
	console.error(err.stack);
	res.status(500).send("Internal Server Error");
});

server.listen(3000, () => {
	console.log("listening on port 3000");
});