/*
Script: Class.Extras.js
	Contains common implementations for custom classes. In Mootools is implemented in <Ajax>, <XHR> and <Fx.Base> and many more.

License:
	MIT-style license.
*/

/*
Class: Chain
	An "Utility" Class. Its methods can be implemented with <Class.implement> into any <Class>.
	Currently implemented in <Fx.Base>, <XHR> and <Ajax>. In <Fx.Base> for example, is used to execute a list of function, one after another, once the effect is completed.
	The functions will not be fired all togheter, but one every completion, to create custom complex animations.

Example:
	(start code)
	var myFx = new Fx.Style('element', 'opacity');

	myFx.start(1,0).chain(function(){
		myFx.start(0,1);
	}).chain(function(){
		myFx.start(1,0);
	}).chain(function(){
		myFx.start(0,1);
	});
	//the element will appear and disappear three times
	(end)
*/

var Chain = new Class({

	/*
	Property: chain
		adds a function to the Chain instance stack.

	Arguments:
		fn - the function to append.
	*/

	chain: function(fn){
		this.chains = this.chains || [];
		this.chains.push(fn);
		return this;
	},

	/*
	Property: callChain
		Executes the first function of the Chain instance stack, then removes it. The first function will then become the second.
	*/

	callChain: function(){
		if (this.chains && this.chains.length) this.chains.shift().delay(10, this);
	},

	/*
	Property: clearChain
		Clears the stack of a Chain instance.
	*/

	clearChain: function(){
		this.chains = [];
	}

});

/*
Class: Events
	An "Utility" Class. Its methods can be implemented with <Class.implement> into any <Class>.
	In <Fx.Base> Class, for example, is used to give the possibility add any number of functions to the Effects events, like onComplete, onStart, onCancel.
	Events in a Class that implements <Events> can be either added as an option, or with addEvent. Never with .options.onEventName.

Example:
	(start code)
	var myFx = new Fx.Style('element', 'opacity').addEvent('onComplete', function(){
		alert('the effect is completed');
	}).addEvent('onComplete', function(){
		alert('I told you the effect is completed');
	});

	myFx.start(0,1);
	//upon completion it will display the 2 alerts, in order.
	(end)

Implementing:
	This class can be implemented into other classes to add the functionality to them.
	Goes well with the <Options> class.

Example:
	(start code)
	var Widget = new Class({
		init: function(){},
		finish: function(){
			this.fireEvent('onComplete');
		}
	});
	Widget.implement(new Events);
	//later...
	var myWidget = new Widget();
	myWidget.addEvent('onComplete', myfunction);
	(end)
*/

var Events = new Class({

	/*
	Property: addEvent
		adds an event to the stack of events of the Class instance.

	Arguments:
		type - string; the event name (e.g. 'onComplete')
		fn - function to execute
	*/

	addEvent: function(type, fn){
		if (fn != Class.empty){
			this.$events = this.$events || {};
			this.$events[type] = this.$events[type] || [];
			this.$events[type].include(fn);
		}
		return this;
	},

	/*
	Property: fireEvent
		fires all events of the specified type in the Class instance.

	Arguments:
		type - string; the event name (e.g. 'onComplete')
		args - array or single object; arguments to pass to the function; if more than one argument, must be an array
		delay - (integer) delay (in ms) to wait to execute the event

	Example:
	(start code)
	var Widget = new Class({
		init: function(arg1, arg2){
			...
			this.fireEvent("onInitialize", [arg1, arg2], 50);
		}
	});
	Widget.implement(new Events);
	(end)
	*/

	fireEvent: function(type, args, delay){
		if (this.$events && this.$events[type]){
			this.$events[type].each(function(fn){
				fn.create({'bind': this, 'delay': delay, 'arguments': args})();
			}, this);
		}
		return this;
	},

	/*
	Property: removeEvent
		removes an event from the stack of events of the Class instance.

	Arguments:
		type - string; the event name (e.g. 'onComplete')
		fn - function that was added
	*/

	removeEvent: function(type, fn){
		if (this.$events && this.$events[type]) this.$events[type].remove(fn);
		return this;
	}

});

/*
Class: Options
	An "Utility" Class. Its methods can be implemented with <Class.implement> into any <Class>.
	Used to automate the options settings, also adding Class <Events> when the option begins with on.

	Example:
		(start code)
		var Widget = new Class({
			options: {
				color: '#fff',
				size: {
					width: 100
					height: 100
				}
			},
			init: function(options){
				this.setOptions(options);
			}
		});
		Widget.implement(new Options);
		//later...
		var myWidget = new Widget({
			color: '#f00',
			size: {
				width: 200
			}
		});
		//myWidget.options = {color: #f00, size: {width: 200, height: 100}}
		(end)
*/

var Options = new Class({

	/*
	Property: setOptions
		sets this.options

	Arguments:
		defaults - object; the default set of options
		options - object; the user entered options. can be empty too.

	Note:
		if your Class has <Events> implemented, every option beginning with on, followed by a capital letter (onComplete) becomes an Class instance event.
	*/

	setOptions: function(){
		this.options = $merge.apply(null, [this.options].extend(arguments));
		if (this.addEvent){
			for (var option in this.options){
				if ($type(this.options[option] == 'function') && (/^on[A-Z]/).test(option)) this.addEvent(option, this.options[option]);
			}
		}
		return this;
	}

});