/*
	Lightbox JS: Fullsize Image Overlays 
	by Lokesh Dhakar - http://www.huddletogether.com

	For more information on this script, visit:
	http://huddletogether.com/projects/lightbox/

	Licensed under the Creative Commons Attribution 2.5 License - http://creativecommons.org/licenses/by/2.5/
	(basically, do anything you want, just leave my name and link)
	
	Table of Contents
	-----------------
	Configuration
	
	Functions
	- getPageScroll()
	- getPageSize()
	- pause()
	- getKey()
	- listenKey()
	- showLightbox()
	- hideLightbox()
	- initLightbox()
	- addLoadEvent()
	
	Function Calls
	- addLoadEvent(initLightbox)

*/

/*
 
  Gil's install toturial:
  1. add <jsp:include page="include/imageBox.jsp" /> in the jsp file.
  2. put a valid href on each image
  3. add onclick="showLightbox(this); return false;" to the a tag
  4. when using SlideShow taglib add: id="zoomLink" to the a tag, and dont forget to add zoomLinkId="zoomLink" to the <tripi:slideshow init tag
  5. SHORTCUT: copy&paste from include/miniartivle.jsp :)
  
 
 */

//
// getPageScroll()
// Returns array with x,y page scroll values.
// Core code from - quirksmode.org
//
function getPageScroll(){

	var yScroll;

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

	arrayPageScroll = new Array('',yScroll) 
	return arrayPageScroll;
}


//
// getPageSize()
// Returns array with page width, height and window width, height
// Core code from - quirksmode.org
// Edit for Firefox by pHaez
//
function getPageSize(){
	
	var xScroll, yScroll;
	
	if (window.innerHeight && window.scrollMaxY) {	
		xScroll = document.body.scrollWidth;
		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
		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 = windowWidth;
	} else {
		pageWidth = xScroll;
	}


	arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
	return arrayPageSize;
}


//
// 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
//
function pause(numberMillis) {
	var now = new Date();
	var exitTime = now.getTime() + numberMillis;
	while (true) {
		now = new Date();
		if (now.getTime() > exitTime)
			return;
	}
}

//
// getKey(key)
// Gets keycode. If 'x' is pressed then it hides the lightbox.
//

function getKey(e){
	if (e == null) { // ie
		keycode = event.keyCode;
	} else { // mozilla
		keycode = e.which;
	}
	key = String.fromCharCode(keycode).toLowerCase();
	
	if(key == 'x'){ hideLightbox(); }
}


//
// listenKey()
//
function listenKey () {	document.onkeypress = getKey; }
	

//
// showLightbox()
// Preloads images. Pleaces new image in lightbox then centers and displays.
//
function showLightbox(slideshowIndex, pictureIndex) {
	var slideshow = window.slideshowArray[slideshowIndex];
	var picture
	if (pictureIndex == undefined)
		pictureIndex = slideshow.currentPictureIndex;
 	var picture = slideshow["pictures"][pictureIndex];
 	if (!picture["zoomAvailable"])
 		return;
	// prep objects
	var objOverlay = $('overlay');
	var objLightbox = $('lightbox');
	var objCaption = $('lightboxCaption');
	var objDescription = $('lightboxDescription');
	var objImage = $('lightboxImage');
	var objLoadingImage = $('loadingImage');
	var objLightboxDetails = $('lightboxDetails');
	
	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();

	// center loadingImage if it exists
	if (objLoadingImage) {
		objLoadingImage.style.top = (arrayPageScroll[1] + ((arrayPageSize[3] - objLoadingImage.height) / 2) + 'px');
		objLoadingImage.style.left = (((arrayPageSize[0] - 25 - objLoadingImage.width) / 2) + 'px');
		objLoadingImage.show();
	}
	// set height of Overlay to take up whole page and show
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	if (navigator.userAgent.indexOf("Firefox")==-1)
		objOverlay.style.width = (arrayPageSize[0] + 'px');
	objOverlay.style.display = "block";

	// preload image
	var imgPreload = new Image();

	imgPreload.onload=function(){
		objImage.src = imgPreload.src;
		// center lightbox and make sure that the top and left values are not negative
		// and the image placed outside the viewport
		var heightRatio =  (arrayPageSize[3]-68) / (imgPreload.height);
		var widthRatio =  (arrayPageSize[2]-40) / (imgPreload.width);
		//var ratio = imgPreload.width/(imgPreload.height/arrayPageSize[3]);
		var ratio = Math.min(heightRatio,widthRatio);
		if (ratio<1) {
			imgPreload.width = (imgPreload.width * ratio);
			imgPreload.height = (imgPreload.height * ratio);
		}
		objImage.width = imgPreload.width;
		var lightboxTop = arrayPageScroll[1] + (Math.max((arrayPageSize[3] - (imgPreload.height+48))/2,0));
		var lightboxLeft = ((arrayPageSize[2] - 20 - imgPreload.width) / 2);
		objLightbox.style.width = imgPreload.width+34 + 'px';
		
		objLightbox.style.top = (lightboxTop < 0) ? "0px" : lightboxTop + "px";
		objLightbox.style.left = (lightboxLeft < 0) ? "0px" : lightboxLeft + "px";
		objLightboxDetails.style.width = imgPreload.width + 10 + 'px';
		
		// Slideshow integration
		var title = "";
		var description = "&nbsp;";
		var pictureCount = slideshow.pictureCount;
		if (pictureCount > 1) {
			title += "<span class=\"lightBoxNavigation\"><a href=\"javascript:void(0);\" onclick=\"hideLightbox(); slideshowArray['" +
				slideshowIndex + "'].gotoPreviousPicture(); slideshowArray['" +
				slideshowIndex + "'].zoom(); return false;\">&lt;</a>";
			title += " " + (slideshow.currentPictureIndex+1) + "/" + pictureCount + " ";
			title += "<a href=\"javascript:void(0);\" onclick=\"hideLightbox(); slideshowArray['" +
				slideshowIndex + "'].gotoNextPicture(); slideshowArray['" +
				slideshowIndex + "'].zoom(); return false;\">&gt;</a></span>";
		}
			
		if (picture["title"] != "")
			title += " <span class=\"lightBoxTitle\">" + picture["title"] + "</span> ";
		if (picture["pictureDate"] != null)
			title += " <span class=\"lightBoxDate\">" + picture["pictureDate"].getDate() + "/" + (picture["pictureDate"].getMonth()+1) + "/" + picture["pictureDate"].getFullYear() + "</span> ";
		if (picture["description"] != "")
			description += picture["description"];
		
		if(title != null && title != ""){
			objCaption.show();
			//objCaption.style.width = imgPreload.width + 'px';
			objCaption.update(title);
		} else {
			objCaption.hide();
		}
		if(description != null && description != ""){
			objDescription.show();
			objDescription.update(description);
		} else {
			objDescription.hide();
		}
		
		// A small pause between the image loading and displaying is required with IE,
		// this prevents the previous image displaying for a short burst causing flicker.
		if (navigator.appVersion.indexOf("MSIE")!=-1){
			pause(250);
		} 

		if (objLoadingImage) {	objLoadingImage.hide(); }

		// Hide select boxes as they will 'peek' through the image in IE
		selects = document.getElementsByTagName("select");
        for (i = 0; i != selects.length; i++) {
                selects[i].style.visibility = "hidden";
        }

	
		objLightbox.style.display = "block";

		// After image is loaded, update the overlay height as the new image might have
		// increased the overall page height.
		arrayPageSize = getPageSize();
		objOverlay.style.height = (arrayPageSize[1] + 'px');
		
		// Check for 'x' keypress
		listenKey();

		return false;
	}

	imgPreload.src = slideshow.imagePrefix + picture["uid"] +  ".jpg";
	
}



//
// hideLightbox()
//
function hideLightbox()
{
	// get objects
	objOverlay = document.getElementById('overlay');
	objLightbox = document.getElementById('lightbox');

	// hide lightbox and overlay
	objOverlay.hide();
	objLightbox.hide();

	// make select boxes visible
	selects = document.getElementsByTagName("select");
    for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "visible";
	}

	// disable keypress listener
	document.onkeypress = '';
}