app.js

var express = require('express'), 
	logfmt = require("logfmt");

var app = express();

var server = require('http').Server(app);

var sio = require('socket.io')(server);

app.use(express.static(__dirname + '/public'));
app.set('views', __dirname + '/views')
app.set('view engine', 'ejs');

app.get('/', function(req, res){
  res.render('index');
});

var port = Number(process.env.PORT || 5000);
server.listen(port, function() {
  console.log("Listening on " + port);
});

var socket,
	players,
	Player = require("./Player").Player;

function init() {
	players = [];
	
	//var socket = sio.listen(server);

	setEventHandlers();
};

/**************************************************
** GAME EVENT HANDLERS
**************************************************/
var setEventHandlers = function() {
	// Socket.IO
	sio.on("connection", onSocketConnection);
};

// New socket connection
function onSocketConnection(client) {
	console.log("New player has connected: "+client.id);

	// Listen for client disconnected
	client.on("disconnect", onClientDisconnect);

	// Listen for new player message
	client.on("new player", onNewPlayer);

	// Listen for move player message
	client.on("move player", onMovePlayer);

	// Listen for chat player message
	client.on("chat player", onChatPlayer);
};

// Socket client has disconnected
function onClientDisconnect() {
	console.log("Player has disconnected: "+this.id);

	var removePlayer = playerById(this.id);

	// Player not found
	if (!removePlayer) {
		console.log("Player not found: "+this.id);
		return;
	};

	// Remove player from players array
	players.splice(players.indexOf(removePlayer), 1);

	// Broadcast removed player to connected socket clients
	this.broadcast.emit("remove player", {id: this.id});
};

// New player has joined
function onNewPlayer(data) {
	// Create a new player
	var newPlayer = new Player(data.x, data.y, data.imageId);
	newPlayer.id = this.id;

	// Broadcast new player to connected socket clients
	this.broadcast.emit("new player", {id: newPlayer.id, x: newPlayer.getX(), y: newPlayer.getY(), imageId: newPlayer.getImageId()});

	// Send existing players to the new player
	var i, existingPlayer;
	for (i = 0; i < players.length; i++) {
		existingPlayer = players[i];
		this.emit("new player", {id: existingPlayer.id, x: existingPlayer.getX(), y: existingPlayer.getY(), imageId: existingPlayer.getImageId()});
	};
		
	// Add new player to the players array
	players.push(newPlayer);
};

// Player has moved
function onMovePlayer(data) {
	// Find player in array
	var movePlayer = playerById(this.id);

	// Player not found
	if (!movePlayer) {
		console.log("Player not found: "+this.id);
		return;
	};

	// Update player position
	movePlayer.setX(data.x);
	movePlayer.setY(data.y);

	// Broadcast updated position to connected socket clients
	this.broadcast.emit("move player", {id: movePlayer.id, x: movePlayer.getX(), y: movePlayer.getY()});
};

// Player chat
function onChatPlayer(data) {
	// Find player in array
	var chatPlayer = playerById(this.id);

	// Player not found
	if (!chatPlayer) {
		console.log("Player not found: "+this.id);
		return;
	};

	chatPlayer.setText(data.text);

	this.broadcast.emit("chat player", {id: chatPlayer.id, text: chatPlayer.getText()});
};


/**************************************************
** GAME HELPER FUNCTIONS
**************************************************/
// Find player by ID
function playerById(id) {
	var i;
	for (i = 0; i < players.length; i++) {
		if (players[i].id == id)
			return players[i];
	};
	
	return false;
};


/**************************************************
** RUN THE GAME
**************************************************/
init();