app.js

var express = require('express'),
    app = express(),
    server = require('http').createServer(app),
    io = require('socket.io').listen(server),
    ent = require('ent'), // Permet de bloquer les caractères HTML (sécurité équivalente à htmlentities en PHP)
    fs = require('fs');//file manager


scoreFileGenerator(); //the scoring file must be created if dont exist

var playerListServerSide = {};
var playGroundId = null;
var scores = {};
var maxPlayer = 5;


app.use(express.static(__dirname + '/public'))
.get('/playground', function(req, res) {
    res.sendfile(__dirname + '/public/playgroundscreen.html');
}).get('/', function(req, res) {
    res.sendfile(__dirname + '/public/playerscreen.html');
})


//to not display useless info in the terminal
io.set('log level', 1);

io.sockets.on('connection', function (socket) {
    
    
    //the playground reset the players(from client side) after it loaded
    socket.on('thePlayGroundHasArrive', function() {
        
        playGroundId = socket.id;
        socket.join('playground');
        socket.broadcast.to('playerSide').emit('timeToStart');
    });
    
    socket.on('newPlayer', function(Player) {
        //redirect if no id
        if( undefined === Player.id || null == Player.id ) {
            console.log('rejected player');
            app.redirect('/');
            return false;
        }
        
        //secure the pseudo and the id
        Player.pseudo = (ent.encode(Player.pseudo)).substr(0, 12);
        Player.id = (ent.encode(Player.id)).substr(0, 50);
        
        //Add the player to the list on the server side
        var oldPlayer = true;
        if(playerListServerSide[socket.id] != Player.id) {
            oldPlayer = false;
            playerListServerSide[socket.id] = Player.id;
        }
          
        socket.join('playerSide');
        
        if( playGroundId == null || Object.keys(playerListServerSide).length > maxPlayer ) {
            socket.emit('youCannotPlay');
            delete playerListServerSide[socket.id];
            return false;
        }
        
        //tell the new player that he can play
        if( !oldPlayer ) socket.emit('readyToPlay');
            
        //pass the new player to the game
        socket.broadcast.to('playground').emit('newPlayerEnterTheGame', Player);
        
    });
    
    //a player just lost
    socket.on('youAreDead', function(playerId) {
        //console.log('suis-je mort ?');
        for(socketId in playerListServerSide) {
            
            if( playerListServerSide[socketId] == playerId ) {
                delete playerListServerSide[socketId];
                break;
            }
            
        }        
        socket.broadcast.to('playerSide').emit('iAmDead', playerId);        
    });
    
    socket.on('youNeedABeer', function(playerId) {
        
        for(socketId in playerListServerSide) {
            
            if( playerListServerSide[socketId] == playerId ) {
                delete playerListServerSide[socketId];
                break;
            }
            
        }
        
        socket.broadcast.to('playerSide').emit('youNeedABeer', playerId);        
    });
    
    socket.on('hereIsMyScore', function(pseudo, score) {
        
        pseudo = ent.encode(pseudo);
        score = parseInt(score);
        
        registerPlayer(pseudo, score, socket);
        
    });
    
    //player movements
    socket.on('touched', function(playerPos) {
        socket.broadcast.to('playground').emit('updatePlayerPos', playerPos);        
    });
    
    
    socket.on('disconnect', function () {
        
        if( socket.id != playGroundId ) {
            socket.broadcast.to('playground').emit('playerLeft', playerListServerSide[socket.id]);
            delete playerListServerSide[socket.id];
        }
        
    });
    
});


//doit etre place en dernier !
server.listen(8090);

function scoreFileGenerator() {
    
    fs.readFile('theScore.txt', 'utf8', function (err,data) {
        if(err) {
            var f = fs.createWriteStream('theScore.txt');
            f.write('{}');
        } else {
            if(data != '') scores = JSON.parse(data);
            else data = '{}';
        }
    })
}

function registerPlayer(pseudo, score, socket) {
    
    fs.readFile('theScore.txt', 'utf8', function (err,data) {
        if (err) {
            return false;
        }
        
        //First Player
        if(data == '{}') {
            
            var stringify =  '{"'+pseudo+'" : '+score+'}';
            
            fs.writeFile('theScore.txt', stringify, [], function() {  });
            
            scores = JSON.parse(stringify);
        } else {
            
            scores = JSON.parse(data);
            var placed = false;
            //is his pseudo already known ?
            if(scores.hasOwnProperty(pseudo)) {
                //is his score better this time ?
                if( scores[pseudo] < score ) delete scores[pseudo];
                else {//if not then don't need to change anything
                    socket.emit('ranking', scores);
                    return ;
                }
            }
            
            //Let's make new scoreObject
            var newResult = {};
            for( key in scores ) {
                if( scores[key] < score) newResult[pseudo] = score;
                newResult[key] = scores[key];
            }
            
            //the worst player? then add it at the end of the list
            if( scores[pseudo] === undefined ) newResult[pseudo] = score;
            
            
                //and finally write in the score file the new results
            fs.writeFile('theScore.txt', JSON.stringify(newResult), [], function() {  });
            
            scores = newResult;
            
        }
        
        socket.emit('ranking', scores);
        
    })
}