JavaScript Loading Tool. Async loading and Syncloading with jquery and google analytics

loadingMachine.js

/* 
JavaScript Loading Tool
Async loading and Syncloading with jquery and google analytics
*/
(function() {
    /* THE WAY OF FILE SETTING
    CASE : javascript file
        {
            'type':'js',            // put 'js
            'src':'hidouki.js',   // put the path of the js file
            'async':true,         // async -> true, sync -> false
            'charset':'UTF-8'   // *optional. put the encoding of the js file
        }
    CASE : Use Google Analytics 
        {
            'type':'ga',        // put 'ga'
            'set': true,        // put true for begin. if you'd like to stop measureing, put false.
            'account':'UA-1111111-11'   // put the account number such as 'UA-XXXXXX-XX'
        }
    CASE : Use jquery
        {
            'type':'jquery',        // put 'jquery'
            'set': true,        // put true for begin. if you'd like to stop using, put false.
            'version':'1.7.1'   // *optional. put the jQuery version you'd like to use. if you don't provide any here, the version will be 1.7.1
        }
      
      
    */
    
    //file settings
    var files = [
        //this is a sample of setting. change here
        {'type':'jquery', 'set':true, 'version':'1.7.1' },
        {'type':'js', 'src':'hidouki.js', 'async':true, 'charset':'UTF-8'},
        {'type':'js', 'src':'douki.js', 'async':false, 'charset':'Shift_JIS'},
        {'type':'js', 'src':'hidouki2.js', 'async':true, 'charset':'Shift_JIS'},
        {'type':'js', 'src':'douki2.js', 'async':false},
        {'type':'ga', 'set': true, 'account':'UA-1111111-11'}
    ]
    
    
    
    // Objects for loading Files
    var loadingMachine = function(files){
        this.files = files;
        this.cnt = 0;
        this.max = (this.files).length;
    }
    
    loadingMachine.prototype = {
        //async loading
        'getAsync' : function(file_obj){
            var self = this;
            setTimeout(function(){
                var script = document.createElement('script');
                    script.type = 'text/javascript';
                    script.src = file_obj.src;
                    script.async = file_obj.async;
                    script.charset = file_obj.charset;
               var elm = document.getElementsByTagName('script')[0]; elm.parentNode.insertBefore(script, elm);
            },0);
            self.cnt++;
            self.main_loop(self.cnt);
        },
        
        //sync loading
        'getSync' : function(file_obj){
            var self = this;
            var makeElem = function(scrp){
                var elm = document.body || document.documentElement;
                elm.appendChild(scrp);
            }
            
            var script = document.createElement('script');
            script.type = 'text/javascript';
            script.src    = file_obj.src;
            script.async = file_obj.async;
            if(file_obj.charset){
                script.charset = file_obj.charset;
            }
            var elm = document.body || document.documentElement;
            elm.appendChild(script);
            
            script.onload = function(){self.cnt++; self.main_loop(self.cnt);}
            script.onreadystatechange = function(){
                switch(script.readyState){
                  case 'complete':
                  case 'loaded' :
                    script.onload();
                    break;
                }
            }
        },
        
        //Google Analytics Defalut Tag
        'gaDef' : function(account){
            window._gaq = window._gaq || [];
            _gaq.push(['_setAccount', account]);
            _gaq.push(['_trackPageview']);
            var src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
            var file = {'type':'js', 'src':src, 'async':true};
            this.getAsync(file);
        },
    
        //jQuery Loading
        'getJquery' : function(ver){
            var ver = ver || "1.7.1";
            var src = "https://ajax.googleapis.com/ajax/libs/jquery/" + ver + "/jquery.min.js"
            var file = {'type':'js', 'src':src, 'async':false};
            this.getSync(file);
        },
    
        //main loop
        'main_loop' : function(cnt){
            //console.log("loop_" +cnt);
            if(typeof files[cnt] === "undefined"){
                return false;
            }else{
            switch (this.files[cnt].type){
                case "js":
                    if(this.files[cnt].async === true){
                        this.getAsync(this.files[cnt]);
                    }else if(this.files[cnt].async === false){
                        this.getSync(this.files[cnt]);
                    }else{            
                        console.log("error");
                   }
                   break;
                case "ga":
                    if(this.files[cnt].set === true){
                        this.gaDef(this.files[cnt].account);
                    }
                    break;
                case "jquery":
                    if(this.files[cnt].set === true && typeof jQuery === "undefined"){

                        this.getJquery(this.files[cnt].version);
                    }
                    break;
                }
            }
        }
    
    //end of prototype
    }
    
    //begin
    var l = new loadingMachine(files);
    l.main_loop(0);
})();