/*
---

name: Events.Pseudos

description: Adds the functionality to add pseudo events

license: MIT-style license

authors:
  - Arian Stolwijk

requires: [Core/Class.Extras, Core/Slick.Parser, More/MooTools.More]

provides: [Events.Pseudos]

...
*/

Events.Pseudos = function(pseudos, addEvent, removeEvent){

	var storeKey = 'monitorEvents:';

	var storageOf = function(object){
		return {
			store: object.store ? function(key, value){
				object.store(storeKey + key, value);
			} : function(key, value){
				(object.$monitorEvents || (object.$monitorEvents = {}))[key] = value;
			},
			retrieve: object.retrieve ? function(key, dflt){
				return object.retrieve(storeKey + key, dflt);
			} : function(key, dflt){
				if (!object.$monitorEvents) return dflt;
				return object.$monitorEvents[key] || dflt;
			}
		};
	};

	var splitType = function(type){
		if (type.indexOf(':') == -1 || !pseudos) return null;

		var parsed = Slick.parse(type).expressions[0][0],
			parsedPseudos = parsed.pseudos,
			l = parsedPseudos.length,
			splits = [];

		while (l--) if (pseudos[parsedPseudos[l].key]){
			splits.push({
				event: parsed.tag,
				value: parsedPseudos[l].value,
				pseudo: parsedPseudos[l].key,
				original: type
			});
		}

		return splits.length ? splits : null;
	};

	var mergePseudoOptions = function(split){
		return Object.merge.apply(this, split.map(function(item){
			return pseudos[item.pseudo].options || {};
		}));
	};

	return {

		addEvent: function(type, fn, internal){
			var split = splitType(type);
			if (!split) return addEvent.call(this, type, fn, internal);

			var storage = storageOf(this),
				events = storage.retrieve(type, []),
				eventType = split[0].event,
				options = mergePseudoOptions(split),
				stack = fn,
				eventOptions = options[eventType] || {},
				args = Array.slice(arguments, 2),
				self = this,
				monitor;

			if (eventOptions.args) args.append(Array.from(eventOptions.args));
			if (eventOptions.base) eventType = eventOptions.base;
			if (eventOptions.onAdd) eventOptions.onAdd(this);

			split.each(function(item){
				var stackFn = stack;
				stack = function(){
					(eventOptions.listener || pseudos[item.pseudo].listener).call(self, item, stackFn, arguments, monitor, options);
				};
			});
			monitor = stack.bind(this);

			events.include({event: fn, monitor: monitor});
			storage.store(type, events);

			addEvent.apply(this, [type, fn].concat(args));
			return addEvent.apply(this, [eventType, monitor].concat(args));
		},

		removeEvent: function(type, fn){
			var split = splitType(type);
			if (!split) return removeEvent.call(this, type, fn);

			var storage = storageOf(this),
				events = storage.retrieve(type);
			if (!events) return this;

			var eventType = split[0].event,
				options = mergePseudoOptions(split),
				eventOptions = options[eventType] || {},
				args = Array.slice(arguments, 2);

			if (eventOptions.args) args.append(Array.from(eventOptions.args));
			if (eventOptions.base) eventType = eventOptions.base;
			if (eventOptions.onRemove) eventOptions.onRemove(this);

			removeEvent.apply(this, [type, fn].concat(args));
			events.each(function(monitor, i){
				if (!fn || monitor.event == fn) removeEvent.apply(this, [eventType, monitor.monitor].concat(args));
				delete events[i];
			}, this);

			storage.store(type, events);
			return this;
		}

	};

};

(function(){

var pseudos = {

	once: {
		listener: function(split, fn, args, monitor){
			fn.apply(this, args);
			this.removeEvent(split.event, monitor)
				.removeEvent(split.original, fn);
		}
	},

	throttle: {
		listener: function(split, fn, args){
			if (!fn._throttled){
				fn.apply(this, args);
				fn._throttled = setTimeout(function(){
					fn._throttled = false;
				}, split.value || 250);
			}
		}
	},

	pause: {
		listener: function(split, fn, args){
			clearTimeout(fn._pause);
			fn._pause = fn.delay(split.value || 250, this, args);
		}
	}

};

Events.definePseudo = function(key, listener){
	pseudos[key] = Type.isFunction(listener) ? {listener: listener} : listener;
	return this;
};

Events.lookupPseudo = function(key){
	return pseudos[key];
};

var proto = Events.prototype;
Events.implement(Events.Pseudos(pseudos, proto.addEvent, proto.removeEvent));

['Request', 'Fx'].each(function(klass){
	if (this[klass]) this[klass].implement(Events.prototype);
});

})();