var Lightbox = {
init: function(options){
this.options = Object.extend({
resizeDuration: 400,
resizeTransition: Fx.Transitions.sineInOut,
initialWidth: 250,
initialHeight: 250,
animateCaption: {In:true,Out:true},
container: document.body,
showControls: false,
showNumbers: true,
descriptions: false,
opacity: 0.8
}, 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').setProperty('id', 'lightbox_pruhlednost').injectInside(this.options.container);
this.center = new Element('div').setProperty('id', 'lightbox_center').setStyles({width: this.options.initialWidth+'px', height: this.options.initialHeight+'px', marginLeft: '-'+(this.options.initialWidth/2)+'px', display: 'none'}).injectInside(this.options.container);
this.image = new Element('div').setProperty('id', 'lightbox_polozka').injectInside(this.center);
this.bottomContainer = new Element('div').setProperty('id', 'lightbox_footer').setStyle('display', 'none').injectInside(this.options.container);
this.bottom = new Element('div').setProperty('id', 'lightbox_bottom').injectInside(this.bottomContainer);

if(this.options.showControls){
this.controlDiv = new Element('div').setProperty('id','lightbox_kontrolni').injectInside(this.bottom);
} else {
this.controlDiv = this.image;
}
this.prevLink = new Element('a').setProperties({id: 'lightbox_predchozi', href: '#'}).setStyle('display', 'none').injectInside(this.controlDiv);
this.nextLink = this.prevLink.clone().setProperty('id', 'lightbox_dalsi').injectInside(this.controlDiv);
this.prevLink.onclick = this.previous.bind(this);
this.nextLink.onclick = this.next.bind(this);
this.closeButton = new Element('a').setProperties({id: 'lightbox_zavreni', href: '#'}).injectInside(this.bottom)
this.closeButton.onclick = this.overlay.onclick = this.close.bind(this);
this.closeButton.onclick = this.image.onclick = this.close.bind(this);
this.caption = new Element('div').setProperty('id', 'lightbox_nahled').injectInside(this.bottom);

if(this.options.descriptions != false){
this.options.descriptions = $$(this.options.descriptions);
this.description = new Element('div').setProperty('id', 'lightbox_nazev').injectInside(this.bottom);
} if(this.options.showNumbers){
this.number = new Element('div').setProperty('id', 'lightbox_cislo').injectInside(this.bottom);
}
new Element('div').setStyle('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({duration: this.options.resizeDuration, transition: this.options.resizeTransition, onComplete: nextEffect}),
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){
this.options.descriptions.each(function(el,i){

if(el.hasClass(link.id)){
this.linkLoc = i;
}
},this);

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() + (window.getHeight() / 15);
this.window = {};
this.window.height = window.getScrollHeight();
this.window.width = window.getScrollWidth();
this.window.top = window.getScrollTop();
this.window.left = window.getScrollLeft();
this.center.setStyles({top: this.top+'px', display: ''});
this.fx.overlay.start(this.options.opacity);
return this.changeImage(imageNum);
},

position: function(){
if(this.options.container == document.body){
var h = window.getScrollHeight()+'px';
var w = window.getScrollWidth()+'px';
this.overlay.setStyles({top: '0px', height: h, width: w});
} else {
var myCoords = this.options.container.getCoordinates();
this.overlay.setStyles({
top: myCoords.top+'px',
height: myCoords.height+'px',
left: myCoords.left+'px',
width: myCoords.width+'px'
});
}
},

setup: function(open){
var elements = $A(document.getElementsByTagName('object'));
if (window.ie) elements.extend(document.getElementsByTagName('select'));
elements.each(function(el){ el.style.visibility = open ? 'hidden' : ''; });
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(){
this.linkLoc --;
return this.changeImage(this.activeImage-1);
},

next: function(){
this.linkLoc ++;
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;
if(this.options.animateCaption.In && this.bottom.offsetHeight){
this.prevLink.style.display = this.nextLink.style.display = 'none';
this.bottom.effect('margin-top', {duration: 300, onComplete: this.loadImage.bind(this)}).start(-this.bottom.offsetHeight);
} else {
this.bottomContainer.style.display = this.prevLink.style.display = this.nextLink.style.display = 'none';
this.loadImage();
}
this.fx.image.hide();
this.center.className = 'lightbox_nacitani';
return false;
},

loadImage: function(){
this.preload = new Image();
this.preload.onload = this.nextEffect.bind(this);
this.preload.src = this.images[this.activeImage][0];
},

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';
if(this.options.showControls){
this.image.style.height = this.preload.height+'px';
} else {
this.image.style.height = this.prevLink.style.height = this.nextLink.style.height = this.preload.height+'px';
}

this.caption.setHTML(this.images[this.activeImage][1] || '');
if(this.options.descriptions != false){
if(this.description.getFirst()){this.description.getFirst().remove()};
var cl = this.options.descriptions[this.linkLoc].clone();
cl.setStyle('display', 'block').injectInside(this.description);
} if(this.options.showNumbers){
this.number.setHTML((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)+'px', height: '0px', marginLeft: this.center.style.marginLeft, display: ''});
this.fx.image.start(1);
var extra = this.caption.getStyle('height').toInt();
if(this.options.descriptions != false){extra += this.description.getStyle('height').toInt()}
if(this.options.showControls){extra += this.controlDiv.getStyle('height').toInt()}
if(this.options.showNumbers){extra += this.number.getStyle('height').toInt()}
var num = (extra-(this.closeButton.getStyle('height').toInt()*2));
if(num < 0){num=0}
this.closeButton.setStyle('marginTop', num+'px');
if(this.activeImage != 0) this.prevLink.style.display = '';
if(this.activeImage != (this.images.length - 1)) this.nextLink.style.display = '';
break;
case 4:
if (this.options.animateCaption.Out){
this.fx.bottom.set(-this.bottom.offsetHeight);
this.bottomContainer.style.height = '';
this.fx.bottom.start(0);
break;
}
this.bottomContainer.style.height = '';
case 5:
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);
this.overlay.setStyles({height: this.window.height+'px', width: this.window.width+'px'});
return false;
}
};