// Based on Mixin.js from MooTools (MIT)
// Copyright (c) 2006-2009 Valerio Proietti, <http://mad4milk.net/>

io.util.Events = (function(){
  var array = io.util.Array,
  
  eventsOf = function(object, type){
  	type = type.replace(/^on([A-Z])/, function(full, first){
  		return first.toLowerCase();
  	});
  	var events = object.$events;
  	return events[type] || (events[type] = []);
  },
  
  removeEventsOfType = function(object, type){
  	array.each(eventsOf(object, type), function(fn){
  		object.removeEvent(type, fn);
  	});
  };
  
  return {
  	$events: {},

  	addEvent: function(type, fn){
  		array.include(eventsOf(this, type), fn);
  		return this;
  	},

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

  	fireEvent: function(type, args){
  		args = [].concat(args);
  		array.each(eventsOf(this, type), function(fn){
  			fn.apply(this, args);
  		}, this);
  		return this;
  	},

  	fireEvents: function(){
  		for (var i = 0; i < arguments.length; i++) this.fireEvent(arguments[i]);
  		return this;
  	},

  	removeEvent: function(type, fn){
			var events = eventsOf(this, type), index = events.indexOf(fn);
			if (index != -1) delete events[index];

  		return this;
  	},

  	removeEvents: function(option){
  	  if (option === null){
  	    var events = this.$events;
				for (var type in events) removeEventsOfType(this, type);
  	  } else {
  	    switch (typeof option){
    			case 'string': removeEventsOfType(this, option); break;
    			case 'object': for (var name in option) this.removeEvent(name, option[name]); break;
    		}
  	  }  		
  		return this;
  	}
  };
})();