//----------------------------------------------------------------------------
//
//	Lightbox v2.04
//	by Lokesh Dhakar - http://www.lokeshdhakar.com
//
//	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.
//
//	Cleaned up using jslint.
//----------------------------------------------------------------------------------

/*global LightboxOptions, Lightbox, Builder, Class, Prototype, $, $$, $w , Effect*/
LightboxOptions = Object.extend({
    fileLoadingImage:        '../../../attachment/lynxmotion/XWiki/Lightbox/loading.gif',     
    fileBottomNavCloseImage: '../../../attachment/lynxmotion/XWiki/Lightbox/closelabel.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"
}, window.LightboxOptions || {});

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

var Lightbox = Class.create();

Lightbox.prototype = {
    imageArray: [],
    activeImage: undefined,
    
    // 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/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="bottomNav">
        //                  <a href="#" id="bottomNavClose">
        //                      <img src="images/close.gif">
        //                  </a>
        //              </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: 'bottomNav'},
                        Builder.node('a', {id: 'bottomNavClose', href: '#' },
                            Builder.node('img', { src: LightboxOptions.fileBottomNavCloseImage })
                        )
                    )
                ])
            )
        ]));


		$('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));
		$('bottomNavClose').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 bottomNav bottomNavClose';   
            $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' });

        var effect = 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.title]);         
        } else {
            // if image is part of a set..
            this.imageArray = 
                $$(imageLink.tagName + '[href][rel="' + imageLink.rel + '"]').
                collect(function (anchor) {
					return [anchor.href, anchor.title];
				}).
                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();
        
        this.changeImage(imageNum);
    },

    //
    //  changeImage()
    //  Hide most elements and preload image in preparation for resizing image container.
    //
    changeImage: function (imageNum) {   
        
        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();
		// HACK: Opera9 does not currently support scriptaculous opacity and appear fx
        this.imageDataContainer.setStyle({opacity: 0.0001});
        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) {
			var scaleXEffect = new Effect.Scale(this.outerImageContainer, yScale, {scaleX: false, duration: this.resizeDuration, queue: 'front'}); 
		}
        if (wDiff != 0) {
			var scaleYEffect = 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();
        var effectAppear = 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();
        }

        var effectParallel = 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();
    },

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

    //
    //  getPageSize()
    //
    getPageSize: function () {
	        
		var xScroll, yScroll, pageHeight, pageWidth, windowWidth, windowHeight;
		
		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;
		}
				
		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];
	}
};

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