var JSLoader = function(options){
	var options	 = options || {};
	this.pointer = 0;
	this.finish	 = options.finish || function(){};
	this.append	 = options.append || null;
	this.queue = {
		length : 0,
		list : [],
		push : function(arg){
			this.list.push(arg);
			this.length++;
		}
	};
	return this;
};
JSLoader.prototype ={

	next : function(){
		var self = this;
		var loader = new JSLoader({
			append : self.append,
			finish : function(){
				self._next();
			}
		});
		var args = [];
		for(var i=0, l=arguments.length; i<l; i++){
			loader.assign(arguments[i]);
		}
		self.assign(function(){
			loader.run();
		});
		return this;
	},

	_next : function(){
		var func = this.queue.list[this.pointer++];
		if(func){
			func();
		}
	},

	assign : function(arg){
		var self = this;
		switch(typeof arg){
		  case 'string' :
			this.queue.push(function(){self.load(arg,{
				append : self.append,
				onload : function(){
					self.report();
				}});
			});
			break;
		  case 'function' :
			this.queue.push(function(){arg();self.report();});
			break;
		}
	},

	report : function(){
		this.queue.length--;
		if(this.queue.length == 0){
			this.finish();
		}
	},

	start : function(){
		this._next();
	},

	run : function(){
		for( var i=0,l=this.queue.length; i<l; i++){
			this.queue.list[i]();
		}
	},

	load : function(src, options){
		var options	  = options || {};
		var element	  = options.append || document.body || document.documentElement;
		var script	  = document.createElement('script');
		script.src	  = src;
		script.type	  = options.type   || 'text/javascript';
		script.onload = options.onload || function(){};
		if(options.charset)
		  script.charset = options.charset;
		if( document.all ){
			script.onreadystatechange = function(){
				switch(script.readyState){
				  case 'complete':
				  case 'loaded' :
					script.onload();
					break;
				}
			};
		}
		element.appendChild(script);
	}
};