/*
---
description: Generates a class that lazily loads the real class on first instantiation
license: LGPL
authors: ['Michael Ficarra']
requires: [Core,Array,Class,Options,Events,Request]
provides: [LazyClass]
... */

var LazyClass;

(function(globalScope){
	LazyClass = new Class({
		Implements: [Options,Events],
		options: {
			path: './{class}.js',
			scope: globalScope,
			classMethods: []
		},

		initialize: function(klass,options){
			this.klass = klass;
			this.setOptions(options);
			this.options.scope = (options||{}).scope || this.constructor.prototype.options.scope;
			this.options.classMethods = $splat(this.options.classMethods);

			var that = this;
			var preparedClass = new Class(function(){
				var klass = that.options.scope[that.klass];
				if(klass===undefined || klass===this.constructor) klass = that.load();
				var F = function(){};
				F.prototype = klass.prototype;
				var o = new F();
				klass.apply(o,arguments);
				return o;
			});
			this.options.classMethods.each(function(method){
				preparedClass[method] = function(){
					var klass = that.options.scope[that.klass];
					if(klass===undefined || klass===this) klass = that.load();
					return klass[method].apply(klass,arguments);
				};
			});
			return this.options.scope[this.klass] = this.preparedClass = preparedClass;
		},

		load: function(){
			var klass,
				path = this.options.path.substitute({'class':this.klass}),
				addToScope = function(){
					klass = this.options.scope[this.klass];
					if(klass===undefined || klass===this.preparedClass) klass = globalScope[this.klass];
					this.options.scope[this.klass] = klass;
					this.fireEvent('load',klass);
				}.bind(this);
			new Request({
				method: 'get',
				url: path,
				async: false,
				onFailure: function(xhr){
					if(Asset && Asset.javascript) Asset.javascript(path);
					/**too ugly for right now** else {
						var o, parent = document.head || ((o=document.getElement('head')) ? o : document.body);
						parent.adopt(new Element('script',{
							type: 'text/javascript',
							src: path
						}));
					}
					var now, start=Date.now(), timeout=5000;
					// UGLY!
					while(!globalScope[this.klass] && (now=Date.now())-start<timeout); */
					addToScope();
				}.bind(this),
				onSuccess: function(js){
					(new Function(js)).call(this.options.scope);
					addToScope();
				}.bind(this)
			}).send();
			return klass;
		}
	});
})(this);

LazyClass.prepare = function(){
	var args = $A(arguments),
		options = {};
	if(['object','hash'].contains($type(args.getLast()))) {
		options = args.getLast();
		args = args.slice(0,-1);
	}
	if($type(arguments[0])=='array') args = arguments[0];

	var preparedClasses = [];
	args.each(function(klass){
		preparedClasses.push(new this(klass,options));
	},this);
	return preparedClasses;
};

/* Copyright 2010 Michael Ficarra
This program is distributed under the (very open)
terms of the GNU Lesser General Public License */