angular.js with socket.io integration

socket.js

'use strict';

app.factory('socket',function ($rootScope){
    var socket = io.connect();
    return {
        on: function (eventName,callback){
            socket.on(eventName,function(){
                var args = [].slice.call(arguments);
                $rootScope.$apply(function(){
                    if(callback){
                        callback.apply(socket,args);
                    }
                });
            });
        },
        emit: function (eventName, data, callback){
            var args = [].slice.call(arguments), cb;
            if( typeof args[args.length-1]  == "function" ){
                cb = args[args.length-1];
                args[args.length-1] = function(){
                    var args = [].slice.call(arguments);
                    $rootScope.$apply(function(){
                        if(cb){
                            cb.apply(socket,args);
                        }
                    });
                };
            }
            socket.emit.apply(socket, args);
        }
    };
});