// websocket-talkie.js
// Sercrod WebSocket Talkie: a simple IP-based talkie demo

const fs = require("fs");
const https = require("https");
const WebSocket = require("ws");

const port = 8443;
const host = "0.0.0.0";
const ws_path = "/";
// const ws_path = "/ws";

const domain = "example.com";

const server = https.createServer({
	key: fs.readFileSync(`/etc/letsencrypt/live/${domain}/privkey.pem`),
	cert: fs.readFileSync(`/etc/letsencrypt/live/${domain}/fullchain.pem`)
});

server.listen(port, host, () => {
	console.log(`Sercrod WebSocket Talkie on wss://${domain}:${port}${ws_path}`);
});

// ip -> Set<ws>
const ip_rooms = new Map();

function get_client_ip(req){
	const forwarded_for = req.headers["x-forwarded-for"];

	if(forwarded_for){
		return String(forwarded_for).split(",")[0].trim();
	}

	return String(req.socket.remoteAddress || "unknown").replace(/^::ffff:/, "");
}

const wss = new WebSocket.Server({
	server: server,
	path: ws_path
});

wss.on("connection", (ws, req) => {
	const ip = get_client_ip(req);

	if(!ip_rooms.has(ip)){
		ip_rooms.set(ip, new Set());
	}

	const set = ip_rooms.get(ip);

	set.add(ws);

	ws.send(`[system] connected (room = ${ip})`);

	ws.on("message", raw => {
		const text = raw.toString();
		const payload = `[${ip}] ${text}`;

		for(const client of set){
			if(client.readyState === WebSocket.OPEN){
				client.send(payload);
			}
		}
	});

	ws.on("close", () => {
		set.delete(ws);

		if(set.size === 0){
			ip_rooms.delete(ip);
		}
	});
});