var express = require("express");
var qs = require("qs");
var proxyaddr = require("proxy-addr");
var {WebSocketServer} = require("ws");

var app = express();
app.set("trust proxy", "loopback");
app.use(express.static("frontend"));
var server = app.listen(process.env.PORT || 924, process.env.ADDRESS);

var wss = new WebSocketServer({server, clientTracking: true});

var chatlog = [];

wss.on("connection", (ws, req) => {
	req.ip = proxyaddr(req, app.get("trust proxy"));
	req.query = qs.parse(req.url.substr(req.url.indexOf('?')+1));

	function broadcast(msg, excludeSelf) {
		if (typeof msg == "object" && !(msg instanceof Buffer)) msg = JSON.stringify(msg);
		for (let ows of wss.clients) if (!(ows == ws && excludeSelf)) ows.send(msg);
	}
	function broadcastChat(message) {
		broadcast({type: "chat", message});
		chatlog.push(message);
		if (chatlog.length >= 100) chatlog.shift();
	}

	ws.user = {
		uid: req.ip,
		nick: req.query.nick || req.ip,
		color: [Math.floor(Math.random()*256),Math.floor(Math.random()*256),Math.floor(Math.random()*256)]
	}
	let t = Array.from(wss.clients).map(ws => ws.user.id);
	for (let i = 0; i < 256; i++) if (!t.includes(i)) { ws.user.id = i; break; }
	if (ws.user.id == null) return ws.close();

	console.log("join", ws.user);

	ws.send(JSON.stringify({
		type: "load",
		id: ws.user.id,
		uid: ws.user.uid,
		users: Array.from(wss.clients).map(x => x.user),
		chatlog
	}));

	broadcast({type: "join", id: ws.user.id, uid: ws.user.uid, nick: ws.user.nick, color: ws.user.color}, true);
	broadcastChat({type: "join", id: ws.user.id, uid: ws.user.uid, nick: ws.user.nick});
	ws.on("close", () => {
		console.log("leave", ws.user);
		broadcast({type: "leave", id: ws.user.id, uid: ws.user.uid, nick: ws.user.nick, color: ws.user.color}, true);
		broadcastChat({type: "leave", id: ws.user.id, uid: ws.user.uid, nick: ws.user.nick})
	});

	ws.on("message", (msg, isBinary) => {
		if (isBinary) {
			broadcast(Buffer.concat([msg, Buffer.from([ws.user.id])]), true);
		} else {
			msg = msg.toString();
			try {
				msg = JSON.parse(msg);
			} catch (error) { return }
			console.log(msg);
			switch (msg.type) {
				case "chat":
					broadcastChat({type: "message", content: msg.message, user: ws.user});
					break;
				case "nick":
					ws.user.nick = msg.nick;
					broadcast({type: "nick", nick: ws.user.nick, id: ws.user.id, uid: ws.user.uid});
					broadcastChat({type: "nick", nick: ws.user.nick, id: ws.user.id});
					break;
			}
		}
	});

});