/*
	Slimbox v1.41 - The ultimate lightweight Lightbox clone
	by Christophe Beyls (http://www.digitalia.be) - MIT-style license.
	Inspired by the original Lightbox v2 by Lokesh Dhakar.
	
	There are some options that you can change in the script. The default values should be just fine, however if you want you can change the following:

	resizeDuration: The duration of the resize animation for width and height, in milliseconds.
	resizeTransition: The transition you want to use for the resize animation. You can choose amongst lots of cool transitions that are part of the optional “Transitions” module of mootools, like “Fx.Transitions.elasticOut”. Many transitions require a longer execution time to look good, so you should adjust the resizeDuration option above as well.
	initialWidth: The initial width of the box, in pixels.
	initialHeight: The initial height of the box, in pixels.
	animateCaption: Boolean; set it to false to disable the caption animation.
	showCounter: Boolean; set it to false to disable the counter at the bottom (“Image X of X”).
*/

var Lightbox = {

	init: function(options){
		this.options = $extend({
			resizeDuration: 850,	//default=400
			resizeTransition: Fx.Transitions.Back.easeOut,	//default=false
			initialWidth: 250,
			initialHeight: 250,
			animateCaption: true,
			showCounter: true
		}, options || {});

		this.anchors = [];
		$each(document.links, function(el){
			if (el.rel && el.rel.test(/^lightbox/i)){
				el.onclick = this.click.pass(el, this);
				this.anchors.push(el);
			}
		}, this);
		this.eventKeyDown = this.keyboardListener.bindAsEventListener(this);
		this.eventPosition = this.position.bind(this);

		this.overlay = new Element('div', {'id': 'lbOverlay'}).injectInside(document.body);

		this.center = new Element('div', {'id': 'lbCenter', 'styles': {'width': this.options.initialWidth, 'height': this.options.initialHeight, 'marginLeft': -(this.options.initialWidth/2), 'display': 'none'}}).injectInside(document.body);
		this.image = new Element('div', {'id': 'lbImage'}).injectInside(this.center);
		this.prevLink = new Element('a', {'id': 'lbPrevLink', 'href': '#', 'styles': {'display': 'none'}}).injectInside(this.image);
		this.nextLink = this.prevLink.clone().setProperty('id', 'lbNextLink').injectInside(this.image);
		this.prevLink.onclick = this.previous.bind(this);
		this.nextLink.onclick = this.next.bind(this);

		this.bottomContainer = new Element('div', {'id': 'lbBottomContainer', 'styles': {'display': 'none'}}).injectInside(document.body);
		this.bottom = new Element('div', {'id': 'lbBottom'}).injectInside(this.bottomContainer);
		new Element('a', {'id': 'lbCloseLink', 'href': '#'}).injectInside(this.bottom).onclick = this.overlay.onclick = this.close.bind(this);
		this.caption = new Element('div', {'id': 'lbCaption'}).injectInside(this.bottom);
		this.number = new Element('div', {'id': 'lbNumber'}).injectInside(this.bottom);
		new Element('div', {'styles': {'clear': 'both'}}).injectInside(this.bottom);

		var nextEffect = this.nextEffect.bind(this);
		this.fx = {
			overlay: this.overlay.effect('opacity', {duration: 500}).hide(),
			resize: this.center.effects($extend({duration: this.options.resizeDuration, onComplete: nextEffect}, this.options.resizeTransition ? {transition: this.options.resizeTransition} : {})),
			image: this.image.effect('opacity', {duration: 500, onComplete: nextEffect}),
			bottom: this.bottom.effect('margin-top', {duration: 400, onComplete: nextEffect})
		};

		this.preloadPrev = new Image();
		this.preloadNext = new Image();
	},

	click: function(link){
		if (link.rel.length == 8) return this.show(link.href, link.title);

		var j, imageNum, images = [];
		this.anchors.each(function(el){
			if (el.rel == link.rel){
				for (j = 0; j < images.length; j++) if(images[j][0] == el.href) break;
				if (j == images.length){
					images.push([el.href, el.title]);
					if (el.href == link.href) imageNum = j;
				}
			}
		}, this);
		return this.open(images, imageNum);
	},

	show: function(url, title){
		return this.open([[url, title]], 0);
	},

	open: function(images, imageNum){
		this.images = images;
		this.position();
		this.setup(true);
		
		/*
		this.top = window.getScrollTop();
		this.top = 0;
		top: 50% !important; 
		Immagine (567) + bordo bianco sopra (10) + bordo bianco sotto (10) + banda bianca caption (43) = 630/2 = 315
		this.top = window.getScrollTop() + (window.getHeight() / 2) -315;
		*/
		
		this.top = window.getScrollTop();
		this.center.setStyles({top: this.top, display: ''});
		this.fx.overlay.start(0.8);
		return this.changeImage(imageNum);
	},

	position: function(){
		this.overlay.setStyles({'top': window.getScrollTop(), 'height': window.getHeight()});
	},

	setup: function(open){
		var elements = $A(document.getElementsByTagName('object'));
		elements.extend(document.getElementsByTagName(window.ie ? 'select' : 'embed'));
		elements.each(function(el){
			if (open) el.lbBackupStyle = el.style.visibility;
			el.style.visibility = open ? 'hidden' : el.lbBackupStyle;
		});
		var fn = open ? 'addEvent' : 'removeEvent';
		window[fn]('scroll', this.eventPosition)[fn]('resize', this.eventPosition);
		document[fn]('keydown', this.eventKeyDown);
		this.step = 0;
	},

	keyboardListener: function(event){
		switch (event.keyCode){
			case 27: case 88: case 67: this.close(); break;
			case 37: case 80: this.previous(); break;	
			case 39: case 78: this.next();
		}
	},

	previous: function(){
		return this.changeImage(this.activeImage-1);
	},

	next: function(){
		return this.changeImage(this.activeImage+1);
	},

	changeImage: function(imageNum){
		if (this.step || (imageNum < 0) || (imageNum >= this.images.length)) return false;
		this.step = 1;
		this.activeImage = imageNum;

		this.bottomContainer.style.display = this.prevLink.style.display = this.nextLink.style.display = 'none';
		this.fx.image.hide();
		this.center.className = 'lbLoading';

		this.preload = new Image();
		this.preload.onload = this.nextEffect.bind(this);
		this.preload.src = this.images[imageNum][0];
		return false;
	},

	nextEffect: function(){
		switch (this.step++){
		case 1:
			this.center.className = '';
			this.image.style.backgroundImage = 'url('+this.images[this.activeImage][0]+')';
			this.image.style.width = this.bottom.style.width = this.preload.width+'px';
			this.image.style.height = this.prevLink.style.height = this.nextLink.style.height = this.preload.height+'px';

			this.caption.setHTML(this.images[this.activeImage][1] || '');
			this.number.setHTML((!this.options.showCounter || (this.images.length == 1)) ? '' : 'Image '+(this.activeImage+1)+' of '+this.images.length);

			if (this.activeImage) this.preloadPrev.src = this.images[this.activeImage-1][0];
			if (this.activeImage != (this.images.length - 1)) this.preloadNext.src = this.images[this.activeImage+1][0];
			if (this.center.clientHeight != this.image.offsetHeight){
				this.fx.resize.start({height: this.image.offsetHeight});
				break;
			}
			this.step++;
		case 2:
			if (this.center.clientWidth != this.image.offsetWidth){
				this.fx.resize.start({width: this.image.offsetWidth, marginLeft: -this.image.offsetWidth/2});
				break;
			}
			this.step++;
		case 3:
			this.bottomContainer.setStyles({top: this.top + this.center.clientHeight, height: 0, marginLeft: this.center.style.marginLeft, display: ''});
			this.fx.image.start(1);
			break;
		case 4:
			if (this.options.animateCaption){
				this.fx.bottom.set(-this.bottom.offsetHeight);
				this.bottomContainer.style.height = '';
				this.fx.bottom.start(0);
				break;
			}
			this.bottomContainer.style.height = '';
		case 5:
			if (this.activeImage) this.prevLink.style.display = '';
			if (this.activeImage != (this.images.length - 1)) this.nextLink.style.display = '';
			this.step = 0;
		}
	},

	close: function(){
		if (this.step < 0) return;
		this.step = -1;
		if (this.preload){
			this.preload.onload = Class.empty;
			this.preload = null;
		}
		for (var f in this.fx) this.fx[f].stop();
		this.center.style.display = this.bottomContainer.style.display = 'none';
		this.fx.overlay.chain(this.setup.pass(false, this)).start(0);
		return false;
	}
};

window.addEvent('domready', Lightbox.init.bind(Lightbox));