// -----------------------------------------------------------------------------------
//
//  Lightbox Slideshow v1.1
//  by Justin Barkhuff - http://www.justinbarkhuff.com/lab/lightbox_slideshow/
//  Updated: 2007-08-15
//
//  Largely based on Lightbox v2.02
//  by Lokesh Dhakar - http://huddletogether.com/projects/lightbox2/
//  3/31/06
//
//  Licensed under the Creative Commons Attribution 2.5 License - http://creativecommons.org/licenses/by/2.5/
//
//  The code inserts html at the bottom of the page that looks similar to this:
//
//  <div id="overlay"></div>
//  <div id="lightbox">
//      <div id="outerImageContainer">
//          <div id="imageContainer">
//              <img id="lightboxImage" />
//              <div id="hoverNav">
//                  <a href="javascript:void(0);" id="prevLinkImg">&laquo; prev</a>
//                  <a href="javascript:void(0);" id="nextLinkImg">next &raquo;</a>
//              </div>
//              <div id="loading">
//                  <a href="javascript:void(0);" id="loadingLink">loading</a>
//              </div>
//          </div>
//      </div>
//      <div id="imageDataContainer">
//          <div id="imageData">
//              <div id="imageDetails">
//                  <span id="caption"></span>
//                  <span id="numberDisplay"></span>
//                  <span id="detailsNav">
//                      <a id="prevLinkDetails" href="javascript:void(0);">&laquo; Previous Slide</a>
//                      <a id="nextLinkDetails" href="javascript:void(0);">Next Slide &raquo;</a>
//                      <a id="slideShowControl" href="javascript:void(0);">Stop Slideshow</a>
//                  </span>
//              </div>
//              <div id="close">
//                  <a id="closeLink" href="javascript:void(0);">close</a>
//              </div>
//          </div>
//      </div>
//  </div>
//
// -----------------------------------------------------------------------------------

//
//  Lightbox Object
//

var Lightbox = {
    activeImage : null,
    badObjects : ['select','object','embed'],
    container : null,
    enableSlideshow : null,
    groupName : null,
    imageArray : [],
    options : null,
    overlayDuration : null,
    overlayOpacity : null,
    playSlides : null,
    refTags : ['a','area'],
    relAttribute : null,
    resizeDuration : null,
    slideShowTimer : null,
    startImage : null,

    //
    // initialize()
    // Constructor sets class properties and configuration options and
    // inserts html at the bottom of the page which is used to display the shadow
    // overlay and the image container.
    //
    initialize: function(options) {
        if (!document.getElementsByTagName){ return; }

        this.options = $H({
            animate : true, // resizing animations
            autoPlay : true, // should slideshow start automatically
            borderSize : 10, // if you adjust the padding in the CSS, you will need to update this variable
            containerID : document, // lightbox container object
            enableSlideshow : true, // enable slideshow feature
            googleAnalytics : false, // track individual image views using Google Analytics
            imageDataLocation : 'south', // location of image caption information
            initImage : '', // ID of image link to automatically launch when upon script initialization
            loop : true, // whether to continuously loop slideshow images
            overlayDuration : .2, // time to fade in shadow overlay
            overlayOpacity : .8, // transparency of shadow overlay
            prefix : '', // ID prefix for all dynamically created html elements
            relAttribute : 'lightbox', // specifies the rel attribute value that triggers lightbox
            resizeSpeed : 7, // controls the speed of the image resizing (1=slowest and 10=fastest)
            showGroupName : false, // show group name of images in image details
            slideTime : 6, // time to display images during slideshow
            strings : { // allows for localization
                closeLink : 'close',
                loadingMsg : 'loading',
                nextLink : 'next &raquo;',
                prevLink : '&laquo; prev',
                startSlideshow : 'start slideshow',
                stopSlideshow : 'stop slideshow',
                numDisplayPrefix : 'Image',
                numDisplaySeparator : 'of'
            }
        }).merge(options);

        if(this.options.animate){
            this.overlayDuration = Math.max(this.options.overlayDuration,0);
            this.options.resizeSpeed = Math.max(Math.min(this.options.resizeSpeed,10),1);
            this.resizeDuration = (11 - this.options.resizeSpeed) * 0.15;
        }else{
            this.overlayDuration = 0;
            this.resizeDuration = 0;
        }

        this.enableSlideshow = this.options.enableSlideshow;
        this.overlayOpacity = Math.max(Math.min(this.options.overlayOpacity,1),0);
        this.playSlides = this.options.autoPlay;
        this.container = $(this.options.containerID);
        this.relAttribute = this.options.relAttribute;
        this.updateImageList();

        var objBody = this.container != document ? this.container : document.getElementsByTagName('body').item(0);

        var objOverlay = document.createElement('div');
        objOverlay.setAttribute('id',this.getID('overlay'));
        objOverlay.style.display = 'none';
        objBody.appendChild(objOverlay);
        Event.observe(objOverlay,'click',this.end.bindAsEventListener(this));

        var objLightbox = document.createElement('div');
        objLightbox.setAttribute('id',this.getID('lightbox'));
        objLightbox.style.display = 'none';
        objBody.appendChild(objLightbox);

        var objImageDataContainer = document.createElement('div');
        objImageDataContainer.setAttribute('id',this.getID('imageDataContainer'));
        objImageDataContainer.className = this.getID('clearfix');

        var objImageData = document.createElement('div');
        objImageData.setAttribute('id',this.getID('imageData'));
        objImageDataContainer.appendChild(objImageData);

        var objImageDetails = document.createElement('div');
        objImageDetails.setAttribute('id',this.getID('imageDetails'));
        objImageData.appendChild(objImageDetails);

        var objCaption = document.createElement('span');
        objCaption.setAttribute('id',this.getID('caption'));
        objImageDetails.appendChild(objCaption);

        var objNumberDisplay = document.createElement('span');
        objNumberDisplay.setAttribute('id',this.getID('numberDisplay'));
        objImageDetails.appendChild(objNumberDisplay);

        var objDetailsNav = document.createElement('span');
        objDetailsNav.setAttribute('id',this.getID('detailsNav'));
        objImageDetails.appendChild(objDetailsNav);

        var objPrevLink = document.createElement('a');
        objPrevLink.setAttribute('id',this.getID('prevLinkDetails'));
        objPrevLink.setAttribute('href','javascript:void(0);');
        objPrevLink.innerHTML = this.options.strings.prevLink;
        objDetailsNav.appendChild(objPrevLink);
        Event.observe(objPrevLink,'click',this.showPrev.bindAsEventListener(this));

        var objNextLink = document.createElement('a');
        objNextLink.setAttribute('id',this.getID('nextLinkDetails'));
        objNextLink.setAttribute('href','javascript:void(0);');
        objNextLink.innerHTML = this.options.strings.nextLink;
        objDetailsNav.appendChild(objNextLink);
        Event.observe(objNextLink,'click',this.showNext.bindAsEventListener(this));

        var objSlideShowControl = document.createElement('a');
        objSlideShowControl.setAttribute('id',this.getID('slideShowControl'));
        objSlideShowControl.setAttribute('href','javascript:void(0);');
        objDetailsNav.appendChild(objSlideShowControl);
        Event.observe(objSlideShowControl,'click',this.toggleSlideShow.bindAsEventListener(this));

        var objClose = document.createElement('div');
        objClose.setAttribute('id',this.getID('close'));
        objImageData.appendChild(objClose);

        var objCloseLink = document.createElement('a');
        objCloseLink.setAttribute('id',this.getID('closeLink'));
        objCloseLink.setAttribute('href','javascript:void(0);');
        objCloseLink.innerHTML = this.options.strings.closeLink;
        objClose.appendChild(objCloseLink);
        Event.observe(objCloseLink,'click',this.end.bindAsEventListener(this));

        if(this.options.imageDataLocation == 'north'){
            objLightbox.appendChild(objImageDataContainer);
        }

        var objOuterImageContainer = document.createElement('div');
        objOuterImageContainer.setAttribute('id',this.getID('outerImageContainer'));
        objLightbox.appendChild(objOuterImageContainer);

        var objImageContainer = document.createElement('div');
        objImageContainer.setAttribute('id',this.getID('imageContainer'));
        objOuterImageContainer.appendChild(objImageContainer);

        var objLightboxImage = document.createElement('img');
        objLightboxImage.setAttribute('id',this.getID('lightboxImage'));
        objImageContainer.appendChild(objLightboxImage);

        var objHoverNav = document.createElement('div');
        objHoverNav.setAttribute('id',this.getID('hoverNav'));
        objImageContainer.appendChild(objHoverNav);

        var objPrevLinkImg = document.createElement('a');
        objPrevLinkImg.setAttribute('id',this.getID('prevLinkImg'));
        objPrevLinkImg.setAttribute('href','javascript:void(0);');
        objHoverNav.appendChild(objPrevLinkImg);
        Event.observe(objPrevLinkImg,'click',this.showPrev.bindAsEventListener(this));

        var objNextLinkImg = document.createElement('a');
        objNextLinkImg.setAttribute('id',this.getID('nextLinkImg'));
        objNextLinkImg.setAttribute('href','javascript:void(0);');
        objHoverNav.appendChild(objNextLinkImg);
        Event.observe(objNextLinkImg,'click',this.showNext.bindAsEventListener(this));

        var objLoading = document.createElement('div');
        objLoading.setAttribute('id',this.getID('loading'));
        objImageContainer.appendChild(objLoading);

        var objLoadingLink = document.createElement('a');
        objLoadingLink.setAttribute('id',this.getID('loadingLink'));
        objLoadingLink.setAttribute('href','javascript:void(0);');
        objLoadingLink.innerHTML = this.options.strings.loadingMsg;
        objLoading.appendChild(objLoadingLink);
        Event.observe(objLoadingLink,'click',this.end.bindAsEventListener(this));

        if(this.options.imageDataLocation != 'north'){
            objLightbox.appendChild(objImageDataContainer);
        }

        if(this.options.initImage != ''){
            this.start($(this.options.initImage));
        }
    },

    //
    //  updateImageList()
    //  Loops through specific tags within 'container' looking for
    // 'lightbox' references and applies onclick events to them.
    //
    updateImageList: function(){
        var el, els, rel;
        for(var i=0; i < this.refTags.length; i++){
            els = this.container.getElementsByTagName(this.refTags[i]);
            for(var j=0; j < els.length; j++){
                el = els[j];
                rel = String(el.getAttribute('rel'));
                if (el.getAttribute('href') && (rel.toLowerCase().match(this.relAttribute))){
                    el.onclick = function(){Lightbox.start(this); return false;}
                }
            }
        }
    },

    //
    //  start()
    //  Display overlay and lightbox. If image is part of a set, add siblings to imageArray.
    //
    start: function(imageLink) {

        this.hideBadObjects();

        // stretch overlay to fill page and fade in
        var pageSize = this.getPageSize();
        $(this.getID('overlay')).setStyle({height:pageSize.pageHeight+'px'});
        new Effect.Appear(this.getID('overlay'), { duration: this.overlayDuration, from: 0, to: this.overlayOpacity });

        this.imageArray = [];
        this.groupName = null;

        var rel = imageLink.getAttribute('rel');
        var imageTitle = '';

        // if image is NOT part of a group..
        if(rel == this.relAttribute){
            // add single image to imageArray
            imageTitle = imageLink.getAttribute('title') ? imageLink.getAttribute('title') : '';
            this.imageArray.push({'link':imageLink.getAttribute('href'), 'title':imageTitle});
            this.startImage = 0;
        } else {
            // if image is part of a group..
            var els = this.container.getElementsByTagName(imageLink.tagName);
            // loop through anchors, find other images in group, and add them to imageArray
            for (var i=0; i<els.length; i++){
                var el = els[i];
                if (el.getAttribute('href') && (el.getAttribute('rel') == rel)){
                    imageTitle = el.getAttribute('title') ? el.getAttribute('title') : '';
                    this.imageArray.push({'link':el.getAttribute('href'),'title':imageTitle});
                    if(el == imageLink){
                        this.startImage = this.imageArray.length-1;
                    }
                }
            }
            // get group name
            this.groupName = rel.substring(this.relAttribute.length+1,rel.length-1);
        }

        // calculate top offset for the lightbox and display
        var pageScroll = this.getPageScroll();
        var lightboxTop = pageScroll.y + (pageSize.winHeight / 15);

        $(this.getID('lightbox')).setStyle({top:lightboxTop+'px'}).show();
        this.changeImage(this.startImage);
    },

    //
    //  changeImage()
    //  Hide most elements and preload image in preparation for resizing image container.
    //
    changeImage: function(imageNum){
        this.activeImage = imageNum;

        this.disableKeyboardNav();
        this.pauseSlideShow();

        // hide elements during transition
        $(this.getID('loading')).show();
        $(this.getID('lightboxImage')).hide();
        $(this.getID('hoverNav')).hide();
        $(this.getID('imageDataContainer')).hide();
        $(this.getID('numberDisplay')).hide();
        $(this.getID('detailsNav')).hide();

        var imgPreloader = new Image();

        // once image is preloaded, resize image container
        imgPreloader.onload=function(){
            $(Lightbox.getID('lightboxImage')).src = imgPreloader.src;
            Lightbox.resizeImageContainer(imgPreloader.width,imgPreloader.height);
        }
        imgPreloader.src = this.imageArray[this.activeImage].link;

        if(this.options.googleAnalytics){
            urchinTracker(this.imageArray[this.activeImage].link);
        }
    },

    //
    //  resizeImageContainer()
    //
    resizeImageContainer: function(imgWidth,imgHeight) {
        // get current height and width
        var cDims = $(this.getID('outerImageContainer')).getDimensions();

        // scalars based on change from old to new
        var xScale = ((imgWidth  + (this.options.borderSize * 2)) / cDims.width) * 100;
        var yScale = ((imgHeight  + (this.options.borderSize * 2)) / cDims.height) * 100;

        // calculate size difference between new and old image, and resize if necessary
        var wDiff = (cDims.width - this.options.borderSize * 2) - imgWidth;
        var hDiff = (cDims.height - this.options.borderSize * 2) - imgHeight;

        if(!( hDiff == 0)){ new Effect.Scale(this.getID('outerImageContainer'), yScale, {scaleX: false, duration: this.resizeDuration, queue: 'front'}); }
        if(!( wDiff == 0)){ new Effect.Scale(this.getID('outerImageContainer'), xScale, {scaleY: false, delay: this.resizeDuration, duration: this.resizeDuration}); }

        // if new and old image are same size and no scaling transition is necessary,
        // do a quick pause to prevent image flicker.
        if((hDiff == 0) && (wDiff == 0)){
            if(navigator.appVersion.indexOf('MSIE')!=-1){ this.pause(250); } else { this.pause(100);}
        }

        $(this.getID('prevLinkImg')).setStyle({height:imgHeight+'px'});
        $(this.getID('nextLinkImg')).setStyle({height:imgHeight+'px'});
        $(this.getID('imageDataContainer')).setStyle({width:(imgWidth+(this.options.borderSize * 2))+'px'});

        this.showImage();
    },

    //
    //  showImage()
    //  Display image and begin preloading neighbors.
    //
    showImage: function(){
        $(this.getID('loading')).hide();
        new Effect.Appear(this.getID('lightboxImage'), { duration: 0.5, queue: 'end', afterFinish: function(){  Lightbox.updateDetails(); } });
        this.preloadNeighborImages();
    },

    //
    //  updateDetails()
    //  Display caption, image number, and bottom nav.
    //
    updateDetails: function() {
        $(this.getID('caption')).show();
        $(this.getID('caption')).update(this.imageArray[this.activeImage].title);

        // if image is part of set display 'Image x of y'
        if(this.imageArray.length > 1){
            var num_display = this.options.strings.numDisplayPrefix + ' ' + eval(this.activeImage + 1) + ' ' + this.options.strings.numDisplaySeparator + ' ' + this.imageArray.length;
            if(this.options.showGroupName && this.groupName != ''){
                num_display += ' '+this.options.strings.numDisplaySeparator+' '+this.groupName;
            }
            $(this.getID('numberDisplay')).update(num_display).show();
            if(!this.enableSlideshow){
                $(this.getID('slideShowControl')).hide();
            }
            $(this.getID('detailsNav')).show();
        }

        new Effect.Parallel(
            [ new Effect.SlideDown( this.getID('imageDataContainer'), { sync: true }),
              new Effect.Appear(this.getID('imageDataContainer'), { sync: true }) ],
            { duration:.65, afterFinish: function() { Lightbox.updateNav();} }
        );
    },

    //
    //  updateNav()
    //  Display appropriate previous and next hover navigation.
    //
    updateNav: function() {
        if(this.imageArray.length > 1){
            $(this.getID('hoverNav')).show();
            if(this.enableSlideshow){
                if(this.playSlides){
                    this.startSlideShow();
                } else {
                    this.stopSlideShow();
                }
            }
        }
        this.enableKeyboardNav();
    },
    //
    //  startSlideShow()
    //  Starts the slide show
    //
    startSlideShow: function(){
        this.playSlides = true;
        this.slideShowTimer = new PeriodicalExecuter(function(pe){ Lightbox.showNext(); pe.stop(); },this.options.slideTime);
        $(this.getID('slideShowControl')).update(this.options.strings.stopSlideshow);
    },

    //
    //  stopSlideShow()
    //  Stops the slide show
    //
    stopSlideShow: function(){
        this.playSlides = false;
        if(this.slideShowTimer){
            this.slideShowTimer.stop();
        }
        $(this.getID('slideShowControl')).update(this.options.strings.startSlideshow);
    },

    //
    //  stopSlideShow()
    //  Stops the slide show
    //
    toggleSlideShow: function(){
        if(this.playSlides){
            this.stopSlideShow();
        }else{
            this.startSlideShow();
        }
    },

    //
    //  pauseSlideShow()
    //  Pauses the slide show (doesn't change the value of this.playSlides)
    //
    pauseSlideShow: function(){
        if(this.slideShowTimer){
            this.slideShowTimer.stop();
        }
    },

    //
    //  showNext()
    //  Display the next image in a group
    //
    showNext : function(){
        if(this.imageArray.length > 1){
            if(!this.options.loop && ((this.activeImage == this.imageArray.length - 1 && this.startImage == 0) || (this.activeImage+1 == this.startImage))){
                return this.end();
            }
            if(this.activeImage == this.imageArray.length - 1){
                this.changeImage(0);
            }else{
                this.changeImage(this.activeImage+1);
            }
        }
    },

    //
    //  showPrev()
    //  Display the next image in a group
    //
    showPrev : function(){
        if(this.imageArray.length > 1){
            if(this.activeImage == 0){
                this.changeImage(this.imageArray.length - 1);
            }else{
                this.changeImage(this.activeImage-1);
            }
        }
    },

    //
    //  showFirst()
    //  Display the first image in a group
    //
    showFirst : function(){
        if(this.imageArray.length > 1){
            this.changeImage(0);
        }
    },

    //
    //  showFirst()
    //  Display the first image in a group
    //
    showLast : function(){
        if(this.imageArray.length > 1){
            this.changeImage(this.imageArray.length - 1);
        }
    },

    //
    //  enableKeyboardNav()
    //
    enableKeyboardNav: function() {
        document.onkeydown = this.keyboardAction;
    },

    //
    //  disableKeyboardNav()
    //
    disableKeyboardNav: function() {
        document.onkeydown = '';
    },

    //
    //  keyboardAction()
    //
    keyboardAction: function(e) {
        if (e == null) { // ie
            keycode = event.keyCode;
        } else { // mozilla
            keycode = e.which;
        }

        key = String.fromCharCode(keycode).toLowerCase();

        if(key == 'x' || key == 'o' || key == 'c'){ // close lightbox
            Lightbox.end();
        } else if(key == 'p' || key == '%'){ // display previous image
            Lightbox.showPrev();
        } else if(key == 'n' || key =='\''){ // display next image
            Lightbox.showNext();
        } else if(key == 'f'){ // display first image
            Lightbox.showFirst();
        } else if(key == 'l'){ // display last image
            Lightbox.showLast();
        } else if(key == 's'){ // toggle slideshow
            if(Lightbox.imageArray.length > 0 && Lightbox.options.enableSlideshow){
                Lightbox.toggleSlideShow();
            }
        }
    },

    //
    //  preloadNeighborImages()
    //  Preload previous and next images.
    //
    preloadNeighborImages: function(){
        var nextImageID = this.imageArray.length - 1 == this.activeImage ? 0 : this.activeImage + 1;
        nextImage = new Image();
        nextImage.src = this.imageArray[nextImageID].link

        var prevImageID = this.activeImage == 0 ? this.imageArray.length - 1 : this.activeImage - 1;
        prevImage = new Image();
        prevImage.src = this.imageArray[prevImageID].link;
    },

    //
    //  end()
    //
    end: function() {
        this.disableKeyboardNav();
        this.pauseSlideShow();
        $(this.getID('lightbox')).hide();
        new Effect.Fade(this.getID('overlay'), { duration:this.overlayDuration });
        this.showBadObjects();
    },

    //
    //  showBadObjects()
    //
    showBadObjects: function (){
        var els;
        var tags = Lightbox.badObjects;
        for(var i=0; i<tags.length; i++){
            els = document.getElementsByTagName(tags[i]);
            for(var j=0; j<els.length; j++){
                $(els[j]).setStyle({visibility:'visible'});
            }
        }
    },

    //
    //  hideBadObjects()
    //
    hideBadObjects: function (){
        var els;
        var tags = Lightbox.badObjects;
        for(var i=0; i<tags.length; i++){
            els = document.getElementsByTagName(tags[i]);
            for(var j=0; j<els.length; j++){
                $(els[j]).setStyle({visibility:'hidden'});
            }
        }
    },

    //
    // pause(numberMillis)
    // Pauses code execution for specified time. Uses busy code, not good.
    // Code from http://www.faqts.com/knowledge_base/view.phtml/aid/1602
    //
    pause: function(numberMillis) {
        var now = new Date();
        var exitTime = now.getTime() + numberMillis;
        while(true){
            now = new Date();
            if (now.getTime() > exitTime)
                return;
        }
    },

    //
    // getPageScroll()
    // Returns array with x,y page scroll values.
    // Core code from - quirksmode.org
    //
    getPageScroll: function(){
        var x,y;
        if (self.pageYOffset) {
            x = self.pageXOffset;
            y = self.pageYOffset;
        } else if (document.documentElement && document.documentElement.scrollTop){  // Explorer 6 Strict
            x = document.documentElement.scrollLeft;
            y = document.documentElement.scrollTop;
        } else if (document.body) {// all other Explorers
            x = document.body.scrollLeft;
            y = document.body.scrollTop;
        }
        return {x:x,y:y};
    },

    //
    // getPageSize()
    // Returns array with page width, height and window width, height
    // Core code from - quirksmode.org
    // Edit for Firefox by pHaez
    //
    getPageSize: function(){
        var scrollX,scrollY,windowX,windowY,pageX,pageY;
        if (window.innerHeight && window.scrollMaxY) {
            scrollX = document.body.scrollWidth;
            scrollY = window.innerHeight + window.scrollMaxY;
        } else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
            scrollX = document.body.scrollWidth;
            scrollY = document.body.scrollHeight;
        } else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
            scrollX = document.body.offsetWidth;
            scrollY = document.body.offsetHeight;
        }

        if (self.innerHeight) { // all except Explorer
            windowX = self.innerWidth;
            windowY = self.innerHeight;
        } else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
            windowX = document.documentElement.clientWidth;
            windowY = document.documentElement.clientHeight;
        } else if (document.body) { // other Explorers
            windowX = document.body.clientWidth;
            windowY = document.body.clientHeight;
        }

        pageY = (scrollY < windowY) ? windowY : scrollY; // for small pages with total height less then height of the viewport
        pageX = (scrollX < windowX) ? windowX : scrollX; // for small pages with total width less then width of the viewport

        return {pageWidth:pageX,pageHeight:pageY,winWidth:windowX,winHeight:windowY};
    },

    //
    // getID()
    // Returns formatted Lightbox element ID
    //
    getID: function(id){
        return this.options.prefix+id;
    }
}

// -----------------------------------------------------------------------------------

Event.observe(window,'load',function(){ Lightbox.initialize(); });