var Loop = new Class({

	loopCount: 0,
	isStopped: true,
	isLooping: false,
	loopMethod: $empty,

	setLoop: function(fn,delay){
		if(this.isLooping) {
			this.stopLoop();
			var wasLooping = true;
		} else {
			var wasLooping = false;
		}
		this.loopMethod = fn;
		this.loopDelay = delay || 3000;
		if(wasLooping) this.startLoop();
		return this;
	},

	stopLoop: function() {
		this.isStopped = true;
		this.isLooping = false;
		$clear(this.periodical);
		return this;
	},

	startLoop: function(delay) {
		if(this.isStopped){
			var delay = (delay) ? delay : this.loopDelay;
			this.isStopped = false;
			this.isLooping = true;
			this.periodical = this.looper.periodical(delay,this);
		};
		return this;
	},

	resetLoop: function(){
		this.loopCount = 0;
		return this;
	},

	looper: function(){
		this.loopCount++;
		this.loopMethod(this.loopCount);
		return this;
	}
});

var SlideShow = new Class({
	
	Implements: [Options, Events, Loop],
		
		options: {
			/*
			onShow: $empty,
			onShowComplete: $empty,
			onReverse: $empty,
			onPlay: $empty,
			onPause: $empty
			*/
			delay: 7000,
			transition: 'crossFade',
			duration: '500',
			autoplay: false
		},
	
	initialize: function(element, options){
		this.setOptions(options);
		this.setLoop(this.showNext, this.options.delay);
		this.element = document.id(element);
		this.slides = this.element.getChildren();
		this.current = this.slides[0];
		this.setup();
		if(this.options.autoplay) this.startLoop();
	},
	
	setup: function(){
	  this.setupElement();
	  this.setupSlides();
		return this;
	},
	
	setupElement: function(){
		var el = this.element;
		if(el.getStyle('position') != 'absolute' && el != document.body) el.setStyle('position','relative');
		return this;
	},
	
	setupSlides: function(){
		this.slides.each(function(slide, index){
			this.storeTransition(slide).reset(slide);
			if(index != 0) slide.setStyle('display','none');
		}, this);
		return this;
	},
	
	storeTransition: function(slide){
		var classes = slide.get('class');
		var transitionRegex = /transition:[a-zA-Z]+/;
		var durationRegex = /duration:[0-9]+/;
		var transition = (classes.match(transitionRegex)) ? classes.match(transitionRegex)[0].split(':')[1] : this.options.transition;
		var duration = (classes.match(durationRegex)) ? classes.match(durationRegex)[0].split(':')[1] : this.options.duration;
		slide.store('ssTransition', transition);
		slide.store('ssDuration', duration);
		return this;
	},
	
	getTransition: function(slide){
		return slide.retrieve('ssTransition');
	},
	
	getDuration: function(slide){
		return slide.retrieve('ssDuration');
	},
	
	show: function(slide){
		this.fireEvent('show');
		slide = (typeof slide == 'number') ? this.slides[slide] : slide;
		if(slide != this.current){
			var transition = this.getTransition(slide);
			var duration = this.getDuration(slide);
			var previous = this.current.setStyle('z-index', 1);
			var next = this.reset(slide);
			this.transitions[transition](previous, next, duration, this);
			(function() { 
				previous.setStyle('display','none');
				this.fireEvent('showComplete');
			}).bind(this).delay(duration);
			this.current = next;
		}
		return this;
	},
	
	reset: function(slide){
		return slide.setStyles({
			'position': 'absolute',
			'z-index': 0,
			'display': 'block',
			'left': 0,
			'top': 0
		}).fade('show');
		return this;
	},
	
	nextSlide: function(){
		var next = this.current.getNext();
		return (next) ? next : this.slides[0];
	},

	previousSlide: function(){
		var previous = this.current.getPrevious();
		return (previous) ? previous : this.slides.getLast();
	},
	
	showNext: function(){
		this.show(this.nextSlide());
		return this;
	},
	
	showPrevious: function(){
		this.show(this.previousSlide());
		return this;
	},
	
	play: function(){
		this.startLoop();
		this.fireEvent('play');
		return this;
	},
	
	pause: function(){
		this.stopLoop();
		this.fireEvent('pause');
		return this;
	},
	
	reverse: function(){
		var fn = (this.loopMethod == this.showNext) ? this.showPrevious : this.showNext;
		this.setLoop(fn, this.options.delay);
		this.fireEvent('reverse');
		return this;
	}
	
});

SlideShow.adders = {
	
	transitions:{},
	
	add: function(className, fn){
		this.transitions[className] = fn;
		this.implement({
			transitions: this.transitions
		});
	},
	
	addAllThese : function(transitions){
		$A(transitions).each(function(transition){
			this.add(transition[0], transition[1]);
		}, this);
	}
	
}

$extend(SlideShow, SlideShow.adders);
SlideShow.implement(SlideShow.adders);

SlideShow.add('fade', function(previous, next, duration, instance){
	previous.set('tween',{duration: duration}).fade('out');
	return this;
});

SlideShow.addAllThese([

	['none', function(previous, next, duration, instance){
		previous.setStyle('display','none');
		return this;
	}],

	['crossFade', function(previous, next, duration, instance){
		previous.set('tween',{duration: duration}).fade('out');
		next.set('tween',{duration: duration}).fade('in');
		return this;
	}],
	
	['fadeThroughBackground', function(previous, next, duration, instance){
		var half = duration/2;
		next.set('tween',{
			duration: half
		}).fade('hide');
		previous.set('tween',{
			duration: half,
			onComplete: function(){
				next.fade('in');
			}
		}).fade('out');
	}],

	['pushLeft', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('width').toInt();
		next.setStyle('left', distance);
		[next, previous].each(function(slide){
			var to = slide.getStyle('left').toInt() - distance;
			slide.set('tween',{duration: duration}).tween('left', to);
		});
		return this;
	}],
	
	['pushRight', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('width').toInt();
		next.setStyle('left', -distance);
		[next, previous].each(function(slide){
			var to = slide.getStyle('left').toInt() + distance;
			slide.set('tween',{duration: duration}).tween('left', to);
		});
		return this;
	}],
	
	['pushDown', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('height').toInt();
		next.setStyle('top', -distance);
		[next, previous].each(function(slide){
			var to = slide.getStyle('top').toInt() + distance;
			slide.set('tween',{duration: duration}).tween('top', to);
		});
		return this;
	}],
	
	['pushUp', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('height').toInt();
		next.setStyle('top', distance);
		[next, previous].each(function(slide){
			var to = slide.getStyle('top').toInt() - distance;
			slide.set('tween',{duration: duration}).tween('top', to);
		});
		return this;
	}],
	
	['blindLeft', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('width').toInt();
		next
			.setStyles({
				'left': distance,
				'z-index': 1
			})
			.set('tween',{duration: duration})
			.tween('left', 0);
		return this;
	}],

	['blindRight', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('width').toInt();
		next
			.setStyles({
				'left': -distance,
				'z-index': 1
			})
			.set('tween',{duration: duration})
			.tween('left', 0);
		return this;
	}],
	
	['blindUp', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('height').toInt();
		next
			.setStyles({
				'top': distance,
				'z-index': 1
			})
			.set('tween',{duration: duration})
			.tween('top', 0);
		return this;
	}],
	
	['blindDown', function(previous, next, duration, instance){
		var distance = instance.element.getStyle('height').toInt();
		next
			.setStyles({
				'top': -distance,
				'z-index': 1
			})
			.set('tween',{duration: duration})
			.tween('top', 0);
		return this;
	}],
	
	['blindDownFade', function(previous, next, duration, instance){
		this.blindDown(previous, next, duration, instance).fade(previous, next, duration, instance);
	}],
	
	['blindUpFade', function(previous, next, duration, instance){
		this.blindUp(previous, next, duration, instance).fade(previous, next, duration, instance);
	}],
	
	['blindLeftFade', function(previous, next, duration, instance){
		this.blindLeft(previous, next, duration, instance).fade(previous, next, duration, instance);
	}],
	
	['blindRightFade', function(previous, next, duration, instance){
		this.blindRight(previous, next, duration, instance).fade(previous, next, duration, instance);
	}]
]);