/*
---

name: Class.Extras

description: Contains Utility Classes that can be implemented into your own Classes to ease the execution of many common tasks.

license: MIT-style license.

requires: Class

provides: [Class.Extras, Chain, Events, Options]

...
*/

(function(){

this.Chain = new Class({

	$chain: [],

	chain: function(){
		this.$chain.append(Array.flatten(arguments));
		return this;
	},

	callChain: function(){
		return (this.$chain.length) ? this.$chain.shift().apply(this, arguments) : false;
	},

	clearChain: function(){
		this.$chain.empty();
		return this;
	}

});

var removeOn = function(string){
	return string.replace(/^on([A-Z])/, function(full, first){
		return first.toLowerCase();
	});
};

this.Events = new Class({

	$events: {},

	addEvent: function(type, fn, internal){
		type = removeOn(type);

		/*<1.2compat>*/
		if (fn == $empty) return this;
		/*</1.2compat>*/

		this.$events[type] = (this.$events[type] || []).include(fn);
		if (internal) fn.internal = true;
		return this;
	},

	addEvents: function(events){
		for (var type in events) this.addEvent(type, events[type]);
		return this;
	},

	fireEvent: function(type, args, delay){
		type = removeOn(type);
		var events = this.$events[type];
		if (!events) return this;
		args = Array.from(args);
		events.each(function(fn){
			if (delay) fn.delay(delay, this, args);
			else fn.apply(this, args);
		}, this);
		return this;
	},
	
	removeEvent: function(type, fn){
		type = removeOn(type);
		var events = this.$events[type];
		if (events && !fn.internal){
			var index =  events.indexOf(fn);
			if (index != -1) delete events[index];
		}
		return this;
	},

	removeEvents: function(events){
		var type;
		if (typeOf(events) == 'object'){
			for (type in events) this.removeEvent(type, events[type]);
			return this;
		}
		if (events) events = removeOn(events);
		for (type in this.$events){
			if (events && events != type) continue;
			var fns = this.$events[type];
			for (var i = fns.length; i--;) this.removeEvent(type, fns[i]);
		}
		return this;
	}

});

this.Options = new Class({

	setOptions: function(){
		var options = this.options = Object.merge.apply(null, [{}, this.options].append(arguments));
		if (!this.addEvent) return this;
		for (var option in options){
			if (typeOf(options[option]) != 'function' || !(/^on[A-Z]/).test(option)) continue;
			this.addEvent(option, options[option]);
			delete options[option];
		}
		return this;
	}

});

})();