server.js

var express = require("express");
var app = express();
var http = require("http").Server(app);
var io = require("socket.io")(http);
var argv = require("yargs").argv;
var auth = require("./auth");

var quizcodes = [];

if (argv.username && argv.password) {
	auth.addAdmin(argv.username, argv.password);
} else {
	console.log(
		"#############################################################"
	);
	console.log(
		"# Authentication for /quizmaster page disabled!             #"
	);
	console.log(
		"# Invoke with --username=user --password=pass if undesired! #"
	);
	console.log(
		"#############################################################"
	);
	auth.setAuthEnabled(false);
}

// determine if minified JavaScript resources are served
var minjs = ".min";
if (argv.debug) {
	console.log("### Serving non-minified JavaScript libraries!");
	minjs = "";
}

// determine port to be used, the default is port 3000
var port = 3000;
if (argv.port) {
	port = argv.port;
}

http.listen(port, function () {
	console.log("listening on *:" + port);
});

app.use(express.static("static"));

app.get("/", function (req, res) {
	res.sendFile(__dirname + "/resources/client.html");
});

app.get("/quizmaster", auth.handleRequest, function (req, res) {
	res.sendFile(__dirname + "/resources/quizmaster.html");
});

app.get("/editor", function (req, res) {
	res.sendFile(__dirname + "/resources/editor.html");
});

app.get("/singleplayer", function (req, res) {
	res.sendFile(__dirname + "/resources/singleplayer.html");
});

app.get("/jquery.js", function (req, res) {
	res.sendFile(__dirname + "/resources/jquery-1.11.1" + minjs + ".js");
});

app.get("/i18next.js", function (req, res) {
	res.sendFile(__dirname + "/resources/i18next-1.9.0" + minjs + ".js");
});

io.on("connection", function (socket) {
	console.log("a user connected");

	socket.on("JoinRoom", function (rooms) {
		if (!rooms || !rooms.length) return;
		console.log("client joins room(s) " + rooms);
		for (var i = 0; i < rooms.length; ++i) {
			socket.join(rooms[i]);
		}
	});

	// deliver discovery requests from clients to quizmasters
	socket.on("DiscoveryRequest", function (request) {
		if (!request || !request.code) return;
		var request = {
			code: request.code,
			clientid: socket.id,
		};
		io.in("quizmaster").emit("DiscoveryRequest", request);
	});

	// deliver discovery responses from quizmasters to client
	socket.on("DiscoveryResponse", function (response) {
		if (!response) return;
		io.in(response.recipient).emit("DiscoveryResponse", response);
	});

	// distribute questions to quiz clients
	socket.on("QuizQuestion", function (questionEnvelope) {
		if (
			!questionEnvelope ||
			!questionEnvelope.question ||
			!questionEnvelope.quizinstance
		)
			return;

		var question = questionEnvelope.question;
		var quizinstance = questionEnvelope.quizinstance;

		if (questionEnvelope.recipient) {
			// if question is targeted at specific client, deliver there
			io.in(questionEnvelope.recipient).emit("QuizQuestion", question);
		} else {
			// otherwise deliver to all clients of this quiz instance
			//console.log(quizinstance + ": " + question.text);
			io.in("clients." + quizinstance).emit("QuizQuestion", question);
		}
	});

	socket.on("RequestQuestion", function (request) {
		if (!request || !request.quizinstance) return;
		console.log("question requested, quizinstance " + request.quizinstance);
		request.clientid = socket.id;
		io.in("quizmaster." + request.quizinstance).emit(
			"RequestQuestion",
			request
		);
	});

	// forward answers to quiz master
	socket.on("QuizAnswer", function (answer) {
		if (!answer || !answer.quizinstance) return;
		// determine number of clients for this quiz
		var room = io.sockets.adapter.rooms["clients." + answer.quizinstance];
		answer.totalClients = room ? Object.keys(room).length : 1;
		io.in("quizmaster." + answer.quizinstance).emit("QuizAnswer", answer);
	});

	// forward correct option to clients
	socket.on("RevealCorrect", function (revealMsg) {
		if (!revealMsg || !revealMsg.quizinstance) return;
		io.in("clients." + revealMsg.quizinstance).emit(
			"RevealCorrect",
			revealMsg.answers
		);
	});

	socket.on("RequestQuizCode", function (request) {
		var code = 1337;
		do {
			code = Math.floor(Math.random() * 100000);
		} while (quizcodes.includes(code));

		quizcodes.unshift(code);
		while (quizcodes.length > 100) {
			quizcodes.pop();
		}

		socket.emit("RequestQuizCodeResponse", { quizcode: "" + code });
	});

	socket.on("pong", function (msg) {
		//console.log("Pong received from client");
	});

	socket.on("disconnect", function () {
		console.log("user disconnected");
	});
});

function sendHeartbeat() {
	setTimeout(sendHeartbeat, 9999);
	io.sockets.emit("ping", "Ping!");
}
setTimeout(sendHeartbeat, 9999);