/**
 * jQuery Lightbox
 * Version 0.5 - 11/29/2007
 * @author Warren Krewenki
 *
 * Changes by:
 * @author Krzysztof Kotowicz <koto at webworkers dot pl>:
 *  - bugfix: multiple instances of Lightbox galleries allowed
 *    (using opts variable instead of $.fn.lightbox.defaults)
 *  - bugfix: use var for local variables in a few functions
 *  - added support for navbarOnTop setting
 *  - added support for displayTitle setting
 *  - added support for slideNavBar setting (with slideNavBarSpeed)
 *  - added support for displayHelp setting
 *  - added support for fitToScreen setting (ported Lightbox VinDSL hack)
 *    (see http://www.huddletogether.com/forum/comments.php?DiscussionID=307)
 *  - plugin now uses jQuery.width() and jQuery.height()
 *  - removed eval() calls
 *  - removed destroyElement - uses jQuery.remove()
 *  - use of prevLinkText, nextLinkText and help
 *  - all strings are now placed in opts.strings to allow for customization/translation
 *
 * Based on Lightbox 2 by Lokesh Dhakar (http://www.huddletogether.com/projects/lightbox2/)
 * Originally written to make use of the Prototype framework, and Script.acalo.us, now altered to use jQuery.
 *
 **/

(function($){
	var opts;

	$.fn.lightbox = function(options){
		// build main options
		opts = $.extend({}, $.fn.lightbox.defaults, options);

		// initalize the lightbox
		$.fn.lightbox.initialize();
		return this.each(function(){
			$(this).click(function(){
				$(this).lightbox.start(this);
				return false;
			});
		});
	};

	// lightbox functions
	$.fn.lightbox.initialize = function(){
		$('#overlay,#lightbox').remove();
		opts.inprogress = false;
		var
			outerImage = '<div id="outerImageContainer"><div id="imageContainer"><img id="lightboxImage"><div id="hoverNav"><div title="' + opts.strings.prevLinkTitle + '" id="prevLink"></div><div id="nextLink" title="' + opts.strings.nextLinkTitle + '"></div></div><div id="loading"><div id="loadingLink"><img src="'+opts.fileLoadingImage+'"></div></div></div></div>',
			imageData = '<div id="imageDataContainer" class="clearfix"><div id="imageData"><div id="imageDetails"><span id="caption"></span><span id="numberDisplay"></span></div><div id="bottomNav">',
			string;

		if (opts.displayHelp)
			imageData += '<span id="helpDisplay">' + opts.strings.help + '</span>';

		imageData += '<div id="bottomNavClose" title="' + opts.strings.closeTitle + '"><img src="'+opts.fileBottomNavCloseImage+'"></div></div></div></div>';

		if (opts.navbarOnTop) {
			string = '<div id="overlay"></div><div id="lightbox">' + imageData + outerImage + '</div>';
			$("body").append(string);
			$("#imageDataContainer").addClass('ontop');
		} else {
			string = '<div id="overlay"></div><div id="lightbox">' + outerImage + imageData + '</div>';
			$("body").append(string);
		}

		$("#overlay").click(function(){ $.fn.lightbox.end(); }).hide();
		$("#lightbox").click(function(){ $.fn.lightbox.end();}).hide();
		$("#loadingLink").click(function(){ $.fn.lightbox.end(); return false;});
		$("#bottomNavClose").click(function(){ $.fn.lightbox.end(); return false; });
		$('#outerImageContainer').width(opts.widthCurrent).height(opts.heightCurrent);
		$('#imageDataContainer').width(opts.widthCurrent);
	};

	$.fn.lightbox.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,windowWidth,windowHeight];
	};


	$.fn.lightbox.getPageScroll = function(){
		var xScroll, yScroll;

		if (self.pageYOffset) {
			yScroll = self.pageYOffset;
			xScroll = self.pageXOffset;
		} else if (document.documentElement && document.documentElement.scrollTop){  // Explorer 6 Strict
			yScroll = document.documentElement.scrollTop;
			xScroll = document.documentElement.scrollLeft;
		} else if (document.body) {// all other Explorers
			yScroll = document.body.scrollTop;
			xScroll = document.body.scrollLeft;
		}

		return [xScroll,yScroll];
	};

	$.fn.lightbox.pause = function(ms){
		var date = new Date;
		while((new Date)-date < ms){}
	};

	$.fn.lightbox.start = function(imageLink){
		var
			arrayPageSize = $.fn.lightbox.getPageSize(),
			anchors = document.getElementsByTagName( imageLink.tagName),
			img, title;

		if ($.browser.msie && $.browser.version < 7){ $("select").css("visibility", "hidden"); }
		$("embed,object").css("visibility", "hidden");

		$("#overlay").hide().css({height: arrayPageSize[1]+'px', opacity : opts.overlayOpacity}).fadeIn();

		opts.imageArray = [];
		imageNum = 0;

		// if image is NOT part of a set..
		if (!imageLink.rel || (imageLink.rel == '')){
			// add single image to Lightbox.imageArray
			img = $("img", imageLink);
			title = opts.displayTitle? (img.attr("title") || img.attr("alt") || imageLink.title || '') : '';
			opts.imageArray.push([imageLink.href, title]);
		} else {
			// if image is part of a set..
			$("a").each(function(){
				if (this.href && (this.rel == imageLink.rel)){
					img = $("img", this);
					title = opts.displayTitle? (img.attr("title") || img.attr("alt") || imageLink.title || '') : '';
					opts.imageArray.push([this.href, title]);
				}
			})


			for(i = 0; i < opts.imageArray.length; i++){
				for(j = opts.imageArray.length-1; j>i; j--){
					if (opts.imageArray[i][0] == opts.imageArray[j][0]){
						opts.imageArray.splice(j,1);
					}
				}
			}
			while(opts.imageArray[imageNum][0] != imageLink.href) { imageNum++;}
		}

		// calculate top and left offset for the lightbox
		var
			arrayPageScroll = $.fn.lightbox.getPageScroll(),
			lightboxTop = arrayPageScroll[1] + (arrayPageSize[3] / 10),
			lightboxLeft = arrayPageScroll[0];

		$('#lightbox').css({top: lightboxTop+'px', left: lightboxLeft+'px'}).show();

		if (!opts.slideNavBar) $('#imageData').hide();

		$.fn.lightbox.changeImage(imageNum);

	};

	$.fn.lightbox.changeImage = function(imageNum){
		if (opts.inprogress == false){
			opts.inprogress = true;
			opts.activeImage = imageNum;	// update global var

			// hide elements during transition
			$('#loading').show();
			$('#lightboxImage,#hoverNav,#prevLink,#nextLink').hide();

			if (opts.slideNavBar) { // delay preloading image until navbar will slide up
				// $('#imageDataContainer').slideUp(opts.navBarSlideSpeed, $.fn.doChangeImage);
				$('#imageDataContainer,#imageData').hide();
				$.fn.doChangeImage();
			} else {
					$.fn.doChangeImage();
			}
		}
	};

	$.fn.doChangeImage = function(){

		imgPreloader = new Image();

		// once image is preloaded, resize image container
		imgPreloader.onload=function(){
			var
				newWidth = imgPreloader.width,
				newHeight = imgPreloader.height;

			if (opts.fitToScreen) {
				var
					arrayPageSize = $.fn.lightbox.getPageSize(),
					ratio,
					initialPageWidth = arrayPageSize[2] - 2 * opts.borderSize,
					initialPageHeight = arrayPageSize[3] - 200;

				if (imgPreloader.height > initialPageHeight)
				{
					newWidth = parseInt((initialPageHeight/imgPreloader.height) * imgPreloader.width);
					newHeight = initialPageHeight;
				}
				else if (imgPreloader.width > initialPageWidth)
				{
					newHeight = parseInt((initialPageWidth/imgPreloader.width) * imgPreloader.height);
					newWidth = initialPageWidth;
				}
			}

			$('#lightboxImage')
				.attr('src', opts.imageArray[opts.activeImage][0])
				.width(newWidth)
				.height(newHeight);
			$.fn.lightbox.resizeImageContainer(newWidth, newHeight);
		}

		imgPreloader.src = opts.imageArray[opts.activeImage][0];
	}

	$.fn.lightbox.end = function(){
		$.fn.lightbox.disableKeyboardNav();
		$('#lightbox').hide();
		$('#overlay').fadeOut();
		if ($.browser.msie && $.browser.version < 7){ $('select').css("visibility", "visible"); }
		$('embed,object').css("visibility", "visible");

		$('#numberDisplay').html('');
	};

	$.fn.lightbox.preloadNeighborImages = function(){
		if ((opts.imageArray.length - 1) > opts.activeImage){
			preloadNextImage = new Image();
			preloadNextImage.src = opts.imageArray[opts.activeImage + 1][0];
		}
		if (opts.activeImage > 0){
			preloadPrevImage = new Image();
			preloadPrevImage.src = opts.imageArray[opts.activeImage - 1][0];
		}
	};

	$.fn.lightbox.keyboardAction = function(e){
		var
			keycode = e? e.keyCode : event.keyCode,
			escapeKey = e? e.DOM_VK_ESCAPE : 27,
			key = String.fromCharCode(keycode).toLowerCase();

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

	$.fn.lightbox.resizeImageContainer = function(imgWidth, imgHeight){
		// get current width and height
		opts.widthCurrent = document.getElementById('outerImageContainer').offsetWidth;
		opts.heightCurrent = document.getElementById('outerImageContainer').offsetHeight;

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

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

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

		$('#imageDataContainer').animate({width: widthNew},opts.resizeSpeed,'linear');
		$('#outerImageContainer').animate({width: widthNew},opts.resizeSpeed,'linear',function(){
			$('#outerImageContainer').animate({height: heightNew},opts.resizeSpeed,'linear',function(){
				$.fn.lightbox.showImage();
			});
		});


		// 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){
			$.fn.lightbox.pause($.browser.msie? 250 : 100);
		}

		$('#prevLink,#nextLink').height(imgHeight);
	};

	$.fn.lightbox.showImage = function(){
		$('#loading').hide();
		$('#lightboxImage').fadeIn("fast");
		$.fn.lightbox.updateDetails();
		$.fn.lightbox.preloadNeighborImages();

		opts.inprogress = false;
	};

	$.fn.lightbox.updateDetails = function(){

		if (opts.imageArray[opts.activeImage][1]){
			$('#caption').html(opts.imageArray[opts.activeImage][1]).show();
		}

		// if image is part of set display 'Image x of x'
		if (opts.imageArray.length > 1){
			var
				nav_html = opts.strings.image + (opts.activeImage + 1) + opts.strings.of + opts.imageArray.length;

			// display previous / next text links
			if (opts.activeImage) {
				nav_html += '&nbsp;<a title="' + opts.strings.prevLinkTitle + '" href="#" id="prevLinkText">' + opts.strings.prevLinkText + "</a>";
			}
			if ((opts.activeImage + 1) < opts.imageArray.length) {
				nav_html += '&nbsp;<a title="' + opts.strings.nextLinkTitle + '" href="#" id="nextLinkText">' + opts.strings.nextLinkText + "</a>";
			}

			$('#numberDisplay').html(nav_html).show();
		}

		if (opts.slideNavBar) {
			$("#imageData").slideDown(opts.navBarSlideSpeed);
		} else {
			$("#imageData").show();
		}

		var arrayPageSize = $.fn.lightbox.getPageSize();
		$('#overlay').height(arrayPageSize[1]);
		$.fn.lightbox.updateNav();
	};

	$.fn.lightbox.updateNav = function(){
		$('#hoverNav').show();

		// if not first image in set, display prev image button
		if (opts.activeImage != 0){
			$('#prevLink,#prevLinkText').show().click(function(){
				$.fn.lightbox.changeImage(opts.activeImage - 1); return false;
			});
		}

		// if not last image in set, display next image button
		if (opts.activeImage != (opts.imageArray.length - 1)){
			$('#nextLink,#nextLinkText').show().click(function(){
				$.fn.lightbox.changeImage(opts.activeImage + 1);
				return false;
			});
		}

		$.fn.lightbox.enableKeyboardNav();
	};


	$.fn.lightbox.enableKeyboardNav = function(){
		document.onkeydown = $.fn.lightbox.keyboardAction;
	};

	$.fn.lightbox.disableKeyboardNav = function(){
		document.onkeydown = '';
	};

	$.fn.lightbox.defaults = {
		fileLoadingImage : 'images/loading.gif',
		fileBottomNavCloseImage : 'images/closelabel.gif',
		overlayOpacity : 0.5,
		borderSize : 10,
		imageArray : [],
		activeImage : null,
		inprogress : false,
		resizeSpeed : 350,
		widthCurrent: 250,
		heightCurrent: 250,
		xScale : 1,
		yScale : 1,
		displayTitle: true,
		navbarOnTop: false,
		slideNavBar: false, // slide nav bar up/down between image resizing transitions
		navBarSlideSpeed: 350,
		displayHelp: false,
		strings : {
			help: ' \u2190 / P - previous image\u00a0\u00a0\u00a0\u00a0\u2192 / N - next image\u00a0\u00a0\u00a0\u00a0ESC / X - close image gallery',
			prevLinkTitle: 'previous image',
			nextLinkTitle: 'next image',
			prevLinkText:  '&laquo; Previous',
			nextLinkText:  'Next &raquo;',
			closeTitle: 'close image gallery',
			image: 'Image ',
			of: ' of '
		},
		fitToScreen: false		// resize images if they are bigger than window
	};
})(jQuery);