// -----------------------------------------------------------------------------------
//
//	Lightbox v2.04
//	by Lokesh Dhakar - http://www.lokeshdhakar.com
//	Last Modification: 2/9/08
//
//	For more information, visit:
//	http://lokeshdhakar.com/projects/lightbox2/
//
//	Licensed under the Creative Commons Attribution 2.5 License - http://creativecommons.org/licenses/by/2.5/
//  	- Free for use in both personal and commercial projects
//		- Attribution requires leaving author name, author link, and the license info intact.
//
//  Thanks: Scott Upton(uptonic.com), Peter-Paul Koch(quirksmode.com), and Thomas Fuchs(mir.aculo.us) for ideas, libs, and snippets.
//  		Artemy Tregubenko (arty.name) for cleanup and help in updating to latest ver of proto-aculous.
//
// -----------------------------------------------------------------------------------
/*

    Table of Contents
    -----------------
    Configuration

    Lightbox Class Declaration
    - initialize()
    - updateImageList()
    - start()
    - changeImage()
    - resizeImageContainer()
    - showImage()
    - updateDetails()
    - updateNav()
    - enableKeyboardNav()
    - disableKeyboardNav()
    - keyboardAction()
    - preloadNeighborImages()
    - end()

    Function Calls
    - document.observe()

*/
// -----------------------------------------------------------------------------------

//
//  Configuration
//
LightboxOptions = Object.extend({
    fileLoadingImage:        '/images/lightbox-loading.gif',

    overlayOpacity: 0.8,   // controls transparency of shadow overlay

    animate: true,         // toggles resizing animations
    resizeSpeed: 7,        // controls the speed of the image resizing animations (1=slowest and 10=fastest)

    borderSize: 10,         //if you adjust the padding in the CSS, you will need to update this variable

	// When grouping images this is used to write: Image # of #.
	// Change it for non-english localization
	labelImage: "Image",
    labelOf: "of",

    slideShowSpeed: 4,
    autoPlay: true
}, window.LightboxOptions || {});

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

var Lightbox = Class.create();

Lightbox.prototype = {
   imageArray: [],
   activeImage: undefined,
   slideShowTimer: null,
   slideShowActive: false,

   // initialize()
   // Constructor runs on completion of the DOM loading. Calls updateImageList and then
   // the function inserts html at the bottom of the page which is used to display the shadow
   // overlay and the image container.
   //
   initialize: function() {

      this.updateImageList();

      this.keyboardAction = this.keyboardAction.bindAsEventListener(this);

      if(LightboxOptions.resizeSpeed > 10) LightboxOptions.resizeSpeed = 10;
      if(LightboxOptions.resizeSpeed < 1) LightboxOptions.resizeSpeed = 1;

      this.resizeDuration = LightboxOptions.animate ? ((11 - LightboxOptions.resizeSpeed) * 0.15) : 0;
      this.overlayDuration = LightboxOptions.animate ? 0.2 : 0;  // shadow fade in/out duration

      // When Lightbox starts it will resize itself from 250 by 250 to the current image dimension.
      // If animations are turned off, it will be hidden as to prevent a flicker of a
      // white 250 by 250 box.
      var size = (LightboxOptions.animate ? 250 : 1) + 'px';


      // 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 style="" id="hoverNav">
      //                  <a href="#" id="prevLink"></a>
      //                  <a href="#" id="nextLink"></a>
      //              </div>
      //              <div id="loading">
      //                  <a href="#" id="loadingLink">
      //                      <img src="/images/lightbox-loading.gif">
      //                  </a>
      //              </div>
      //          </div>
      //      </div>
      //      <div id="imageDataContainer">
      //          <div id="imageData">
      //              <div id="imageDetails">
      //                  <span id="caption"></span>
      //                  <span id="numberDisplay"></span>
      //              </div>
      //              <div id="bottomNavContainer">
      //                  <div id="bottomNav">
      //                      <a href="#" id="bottomNavPrevLink"></a>
      //                      <a href="#" id="bottomNavPlayLink"></a>
      //                      <a href="#" id="bottomNavPauseLink"></a>
      //                      <a href="#" id="bottomNavNextLink"></a>
      //                      <a href="#" id="bottomNavCloseLink"></a>
      //                  </div>
      //                  <div id="clearFloat"></div>
      //              </div>
      //              <div id="clearFloat"></div>
      //          </div>
      //      </div>
      //  </div>


      var objBody = $$('body')[0];

      objBody.appendChild(Builder.node('div', { id: 'overlay' }));

      objBody.appendChild(Builder.node('div', { id: 'lightbox' }, [
            Builder.node('div', { id: 'outerImageContainer' },
                Builder.node('div', { id: 'imageContainer' }, [
                    Builder.node('img', { id: 'lightboxImage' }),
                    Builder.node('div', { id: 'hoverNav' }, [
                        Builder.node('a', { id: 'prevLink', href: '#' }),
                        Builder.node('a', { id: 'nextLink', href: '#' })
                    ]),
                    Builder.node('div', { id: 'loading' },
                        Builder.node('a', { id: 'loadingLink', href: '#' },
                            Builder.node('img', { src: LightboxOptions.fileLoadingImage })
                        )
                    )
                ])
            ),
            Builder.node('div', { id: 'imageDataContainer' },
                Builder.node('div', { id: 'imageData' }, [
                    Builder.node('div', { id: 'imageDetails' }, [
                        Builder.node('span', { id: 'caption' }),
                        Builder.node('span', { id: 'numberDisplay' })
                    ]),
                    Builder.node('div', { id: 'bottomNavContainer' }, [
                        Builder.node('div', { id: 'bottomNav' }, [
                            Builder.node('a', { id: 'bottomNavPrevLink', href: '#' }),
                            Builder.node('a', { id: 'bottomNavPlayLink', href: '#' }),
                            Builder.node('a', { id: 'bottomNavPauseLink', href: '#' }),
                            Builder.node('a', { id: 'bottomNavNextLink', href: '#' }),
                            Builder.node('a', { id: 'bottomNavCloseLink', href: '#' })
                        ]),
                        Builder.node('div', { id: 'clearFloat' })
                    ]),
                    Builder.node('div', { id: 'clearFloat' })
                ])
            )
        ]));


      $('overlay').hide().observe('click', (function() { this.end(); }).bind(this));
      $('lightbox').hide().observe('click', (function(event) { if(event.element().id == 'lightbox') this.end(); }).bind(this));
      $('outerImageContainer').setStyle({ width: size, height: size });

      $('prevLink').observe('click', (function(event) { event.stop(); this.changeImage(this.activeImage - 1); }).bindAsEventListener(this));
      $('nextLink').observe('click', (function(event) { event.stop(); this.changeImage(this.activeImage + 1); }).bindAsEventListener(this));

      $('loadingLink').observe('click', (function(event) { event.stop(); this.end(); }).bind(this));

      $('bottomNavPrevLink').observe('click', (function(event) { event.stop(); this.changeImage(this.activeImage - 1); }).bindAsEventListener(this));
      $('bottomNavPlayLink').observe('click', (function(event) { event.stop(); this.startSlideShow(); }).bindAsEventListener(this));
      $('bottomNavPauseLink').observe('click', (function(event) { event.stop(); this.stopSlideShow(); }).bindAsEventListener(this));
      $('bottomNavNextLink').observe('click', (function(event) { event.stop(); this.changeImage(this.activeImage + 1); }).bindAsEventListener(this));
      $('bottomNavCloseLink').observe('click', (function(event) { event.stop(); this.end(); }).bind(this));

      var th = this;
      (function() {
         var ids =
                'overlay lightbox outerImageContainer imageContainer lightboxImage hoverNav prevLink nextLink loading loadingLink ' +
                'imageDataContainer imageData imageDetails caption numberDisplay bottomNavContainer bottomNav ' +
                'bottomNavPrevLink bottomNavPlayLink bottomNavPauseLink bottomNavNextLink bottomNavCloseLink';
         $w(ids).each(function(id) { th[id] = $(id); });
      }).defer();
   },

   //
   // updateImageList()
   // Loops through anchor tags looking for 'lightbox' references and applies onclick
   // events to appropriate links. You can rerun after dynamically adding images w/ajax.
   //
   updateImageList: function() {
      this.updateImageList = Prototype.emptyFunction;

      document.observe('click', (function(event) {
         var target = event.findElement('a[rel^=lightbox]') || event.findElement('area[rel^=lightbox]');
         if(target) {
            event.stop();
            this.start(target);
         }
      }).bind(this));
   },

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

      $$('select', 'object', 'embed').each(function(node) { node.style.visibility = 'hidden' });

      // stretch overlay to fill page and fade in
      var arrayPageSize = this.getPageSize();
      $('overlay').setStyle({ width: arrayPageSize[0] + 'px', height: arrayPageSize[1] + 'px' });

      new Effect.Appear(this.overlay, { duration: this.overlayDuration, from: 0.0, to: LightboxOptions.overlayOpacity });

      this.imageArray = [];
      var imageNum = 0;

      if((imageLink.rel == 'lightbox')) {
         // if image is NOT part of a set, add single image to imageArray
         this.imageArray.push([imageLink.href, imageLink.getAttribute("lightboxtitle")]);
      } else {
         // if image is part of a set..
         this.imageArray =
                $$(imageLink.tagName + '[href][rel="' + imageLink.rel + '"]').
                collect(function(anchor) { return [anchor.href, anchor.getAttribute("lightboxtitle")]; }).
                uniq();

         while(this.imageArray[imageNum][0] != imageLink.href) { imageNum++; }
      }

      // calculate top and left offset for the lightbox
      var arrayPageScroll = document.viewport.getScrollOffsets();
      var lightboxTop = arrayPageScroll[1] + (document.viewport.getHeight() / 10);
      var lightboxLeft = arrayPageScroll[0];
      this.lightbox.setStyle({ top: lightboxTop + 'px', left: lightboxLeft + 'px' }).show();

      if(this.imageArray.length > 1)
      {
         this.slideShowActive = LightboxOptions.autoPlay;
      }

      this.changeImage(imageNum);
   },

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

      this.pauseSlideShow();

      this.activeImage = imageNum; // update global var

      // hide elements during transition
      if(LightboxOptions.animate) this.loading.show();
      this.lightboxImage.hide();
      this.hoverNav.hide();

      this.prevLink.hide();
      this.nextLink.hide();
      // this.bottomNavPrevLink.hide();
      // this.bottomNavNextLink.hide();

      // HACK: Opera9 does not currently support scriptaculous opacity and appear fx
      this.imageDataContainer.setStyle({ opacity: .0001 });
      this.numberDisplay.hide();

      var imgPreloader = new Image();

      // once image is preloaded, resize image container

      imgPreloader.onload = (function() {
         this.lightboxImage.src = this.imageArray[this.activeImage][0];
         this.resizeImageContainer(imgPreloader.width, imgPreloader.height);
      }).bind(this);
      imgPreloader.src = this.imageArray[this.activeImage][0];
   },

   //
   //  resizeImageContainer()
   //
   resizeImageContainer: function(imgWidth, imgHeight) {

      // get current width and height
      var widthCurrent = this.outerImageContainer.getWidth();
      var heightCurrent = this.outerImageContainer.getHeight();

      // get new width and height
      var widthNew = (imgWidth + LightboxOptions.borderSize * 2);
      var heightNew = (imgHeight + LightboxOptions.borderSize * 2);

      // scalars based on change from old to new
      var xScale = (widthNew / widthCurrent) * 100;
      var yScale = (heightNew / heightCurrent) * 100;

      // calculate size difference between new and old image, and resize if necessary
      var wDiff = widthCurrent - widthNew;
      var hDiff = heightCurrent - heightNew;

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

      // if new and old image are same size and no scaling transition is necessary,
      // do a quick pause to prevent image flicker.
      var timeout = 0;
      if((hDiff == 0) && (wDiff == 0)) {
         timeout = 100;
         if(Prototype.Browser.IE) timeout = 250;
      }

      (function() {
         this.prevLink.setStyle({ height: imgHeight + 'px' });
         this.nextLink.setStyle({ height: imgHeight + 'px' });
         this.imageDataContainer.setStyle({ width: widthNew + 'px' });

         this.showImage();
      }).bind(this).delay(timeout / 1000);
   },

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

   //
   //  updateDetails()
   //  Display caption, image number, and bottom nav.
   //
   updateDetails: function() {

      // if caption is not null
      if(this.imageArray[this.activeImage][1] != "") {
         this.caption.update(this.imageArray[this.activeImage][1]).show();
      }

      // if image is part of set display 'Image x of x'
      if(this.imageArray.length > 1) {
         this.numberDisplay.update(LightboxOptions.labelImage + ' ' + (this.activeImage + 1) + ' ' + LightboxOptions.labelOf + '  ' + this.imageArray.length).show();
      }

      // if not first image in set, display prev image button
      if(this.activeImage > 0) {
         this.bottomNavPrevLink.show();
      } else {
         this.bottomNavPrevLink.hide();
      }

      // if not last image in set, display next image button
      if(this.activeImage < (this.imageArray.length - 1)) {
         this.bottomNavCloseLink.style.marginLeft = "0px";
         this.bottomNavNextLink.show();
      } else {
         this.bottomNavCloseLink.style.marginLeft = "32px";
         this.bottomNavNextLink.hide();
      }

      // update play/pause
      if(this.slideShowActive) {
         this.bottomNavPlayLink.hide();
         this.bottomNavPauseLink.show();
      } else {
         if(this.imageArray.length == 1) {
            this.bottomNavPlayLink.hide();
         } else {
            this.bottomNavPlayLink.show();
         }

         this.bottomNavPauseLink.hide();
      }

      new Effect.Parallel(
            [
                new Effect.SlideDown(this.imageDataContainer, { sync: true, duration: this.resizeDuration, from: 0.0, to: 1.0 }),
                new Effect.Appear(this.imageDataContainer, { sync: true, duration: this.resizeDuration })
            ],
            {
               duration: this.resizeDuration,
               afterFinish: (function() {
                  // update overlay size and update nav
                  var arrayPageSize = this.getPageSize();
                  this.overlay.setStyle({ height: arrayPageSize[1] + 'px' });
                  this.updateNav();
               }).bind(this)
            }
        );
   },

   //
   //  updateNav()
   //  Display appropriate previous and next hover navigation.
   //
   updateNav: function() {

      this.hoverNav.show();

      // if not first image in set, display prev image button
      if(this.activeImage > 0) this.prevLink.show();

      // if not last image in set, display next image button
      if(this.activeImage < (this.imageArray.length - 1)) this.nextLink.show();

      this.enableKeyboardNav();

      if(this.slideShowActive) this.startSlideShow();
   },

   //
   //  enableKeyboardNav()
   //
   enableKeyboardNav: function() {
      document.observe('keydown', this.keyboardAction);
   },

   //
   //  disableKeyboardNav()
   //
   disableKeyboardNav: function() {
      document.stopObserving('keydown', this.keyboardAction);
   },

   //
   //  keyboardAction()
   //
   keyboardAction: function(event) {
      var keycode = event.keyCode;

      var escapeKey;
      if(event.DOM_VK_ESCAPE) {  // mozilla
         escapeKey = event.DOM_VK_ESCAPE;
      } else { // ie
         escapeKey = 27;
      }

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

      if(key.match(/x|o|c/) || (keycode == escapeKey)) { // close lightbox
         this.end();
      } else if((key == 'p') || (keycode == 37)) { // display previous image
         if(this.activeImage != 0) {
            this.disableKeyboardNav();
            this.changeImage(this.activeImage - 1);
         }
      } else if((key == 'n') || (keycode == 39)) { // display next image
         if(this.activeImage != (this.imageArray.length - 1)) {
            this.disableKeyboardNav();
            this.changeImage(this.activeImage + 1);
         }
      }
   },

   //
   //  preloadNeighborImages()
   //  Preload previous and next images.
   //
   preloadNeighborImages: function() {
      var preloadNextImage, preloadPrevImage;
      if(this.imageArray.length > this.activeImage + 1) {
         preloadNextImage = new Image();
         preloadNextImage.src = this.imageArray[this.activeImage + 1][0];
      }
      if(this.activeImage > 0) {
         preloadPrevImage = new Image();
         preloadPrevImage.src = this.imageArray[this.activeImage - 1][0];
      }

   },

   //
   //  end()
   //
   end: function() {
      this.pauseSlideShow();
      this.disableKeyboardNav();
      this.lightbox.hide();

      this.slideShowActive = false;

      new Effect.Fade(this.overlay, { duration: this.overlayDuration });
      $$('select', 'object', 'embed').each(function(node) { node.style.visibility = 'visible' });
   },

   //
   //  getPageSize()
   //
   getPageSize: function() {

      var xScroll, yScroll;

      if(window.innerHeight && window.scrollMaxY) {
         xScroll = window.innerWidth + window.scrollMaxX;
         yScroll = window.innerHeight + window.scrollMaxY;
      } else if(document.body.scrollHeight > document.body.offsetHeight) { // all but Explorer Mac
         xScroll = document.body.scrollWidth;
         yScroll = document.body.scrollHeight;
      } else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
         xScroll = document.body.offsetWidth;
         yScroll = document.body.offsetHeight;
      }

      var windowWidth, windowHeight;

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

      // for small pages with total height less then height of the viewport
      if(yScroll < windowHeight) {
         pageHeight = windowHeight;
      } else {
         pageHeight = yScroll;
      }

      // for small pages with total width less then width of the viewport
      if(xScroll < windowWidth) {
         pageWidth = xScroll;
      } else {
         pageWidth = windowWidth;
      }

      return [pageWidth, pageHeight];
   },

   startSlideShow: function() {
      this.slideShowActive = true;

      this.slideShowTimer = new PeriodicalExecuter(
            (function(event) {
               this.slideShowTimer.stop();
               if(this.activeImage == this.imageArray.length - 1) {
                   this.changeImage(0);
               } else {
                   this.changeImage(this.activeImage + 1);
               }
            }).bind(this),
            LightboxOptions.slideShowSpeed);

      this.bottomNavPlayLink.hide();
      this.bottomNavPauseLink.show();
   },

   stopSlideShow: function() {
      this.slideShowActive = false;

      if(this.slideShowTimer) {
         this.slideShowTimer.stop();
      }

      this.bottomNavPauseLink.hide();
      this.bottomNavPlayLink.show();
   },

   pauseSlideShow: function() {
      if(this.slideShowTimer) {
         this.slideShowTimer.stop();
      }
   }
}

document.observe('dom:loaded', function () { new Lightbox(); });