/*
     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)

*/



//
// Configuration
//

// If you would like to use a custom loading image or close button reference them in the next two lines.
var loadingImage = 'images/loading.gif';          
var closeButton = 'images/close.gif';          





//
// 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(objLink)
{
     
     // prep objects
     var objOverlay = document.getElementById('overlay');
     var objLightbox = document.getElementById('lightbox');
     var objCaption = document.getElementById('lightboxCaption');
     var objImage = document.getElementById('lightboxImage');
     var objLoadingImage = document.getElementById('loadingImage');
     var objLightboxDetails = document.getElementById('lightboxDetails');

     
     var arrayPageSize = getPageSize();
     var arrayPageScroll = getPageScroll();

     // center loadingImage if it exists
     if (objLoadingImage) {
          objLoadingImage.style.top = (arrayPageScroll[1] + ((arrayPageSize[3] - 35 - objLoadingImage.height) / 2) + 'px');
          objLoadingImage.style.left = (((arrayPageSize[0] - 20 - objLoadingImage.width) / 2) + 'px');
          objLoadingImage.style.display = 'block';
     }

     // set height of Overlay to take up whole page and show
     objOverlay.style.height = (arrayPageSize[1] + 'px');
     objOverlay.style.display = 'block';

     // preload image
     imgPreload = new Image();

     imgPreload.onload=function(){
          objImage.src = objLink.href;

          // center lightbox and make sure that the top and left values are not negative
          // and the image placed outside the viewport
          var lightboxTop = arrayPageScroll[1] + ((arrayPageSize[3] - 35 - imgPreload.height) / 2);
          var lightboxLeft = ((arrayPageSize[0] - 20 - imgPreload.width) / 2);
          
          objLightbox.style.top = (lightboxTop < 0) ? "0px" : lightboxTop + "px";
          objLightbox.style.left = (lightboxLeft < 0) ? "0px" : lightboxLeft + "px";


          objLightboxDetails.style.width = imgPreload.width + 'px';
          
          if(objLink.getAttribute('title')){
               objCaption.style.display = 'block';
               //objCaption.style.width = imgPreload.width + 'px';
               objCaption.innerHTML = objLink.getAttribute('title');
          } else {
               objCaption.style.display = 'none';
          }
          
          // 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.style.display = 'none'; }

          // 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 = objLink.href;
     
}




//
// flashLightbox()
// Preloads images. Pleaces new image in lightbox then centers and displays.
//
function flashLightbox(imgURL,flashTitle)
{
     
     
     // prep objects
     var objOverlay = document.getElementById('overlay');
     var objLightbox = document.getElementById('lightbox');
     var objCaption = document.getElementById('lightboxCaption');
     var objImage = document.getElementById('lightboxImage');
     var objLoadingImage = document.getElementById('loadingImage');
     var objLightboxDetails = document.getElementById('lightboxDetails');

     
     var arrayPageSize = getPageSize();
     var arrayPageScroll = getPageScroll();

     // center loadingImage if it exists
     if (objLoadingImage) {
          objLoadingImage.style.top = (arrayPageScroll[1] + ((arrayPageSize[3] - 35 - objLoadingImage.height) / 2) + 'px');
          objLoadingImage.style.left = (((arrayPageSize[0] - 20 - objLoadingImage.width) / 2) + 'px');
          objLoadingImage.style.display = 'block';
     }

     // set height of Overlay to take up whole page and show
     objOverlay.style.height = (arrayPageSize[1] + 'px');
     objOverlay.style.display = 'block';

     // preload image
     imgPreload = new Image();

     imgPreload.onload=function(){
          objImage.src = imgURL;

          // center lightbox and make sure that the top and left values are not negative
          // and the image placed outside the viewport
          var lightboxTop = arrayPageScroll[1] + ((arrayPageSize[3] - 35 - imgPreload.height) / 2);
          var lightboxLeft = ((arrayPageSize[0] - 20 - imgPreload.width) / 2);
          
          objLightbox.style.top = (lightboxTop < 0) ? "0px" : lightboxTop + "px";
          objLightbox.style.left = (lightboxLeft < 0) ? "0px" : lightboxLeft + "px";


          objLightboxDetails.style.width = imgPreload.width + 'px';
          
          if(flashTitle!=undefined){
               objCaption.style.display = 'block';
               //objCaption.style.width = imgPreload.width + 'px';
               objCaption.innerHTML = flashTitle;
          } else {
               objCaption.style.display = 'none';
          }
          
          // 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.style.display = 'none'; }

          // 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 = imgURL;
     
}





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

     // hide lightbox and overlay
     objOverlay.style.display = 'none';
     objLightbox.style.display = 'none';

     // 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 = '';
}




//
// initLightbox()
// Function runs on window load, going through link tags looking for rel="lightbox".
// These links receive onclick events that enable the lightbox display for their targets.
// The function also inserts html markup at the top of the page which will be used as a
// container for the overlay pattern and the inline image.
//
function initLightbox()
{
     
     if (!document.getElementsByTagName){ return; }
     var anchors = document.getElementsByTagName("a");

     // loop through all anchor tags
     for (var i=0; i<anchors.length; i++){
          var anchor = anchors[i];

          if (anchor.getAttribute("href") && (anchor.getAttribute("rel") == "lightbox")){
               anchor.onclick = function () {showLightbox(this); return false;}
          }
     }

     // the rest of this code inserts html at the top of the page that looks like this:
     //
     // <div id="overlay">
     //          <a href="#" onclick="hideLightbox(); return false;"><img id="loadingImage" /></a>
     //     </div>
     // <div id="lightbox">
     //          <a href="#" onclick="hideLightbox(); return false;" title="kliknij w dowolne miejsce aby zamkn±æ obrazek">
     //               <img id="closeButton" />          
     //               <img id="lightboxImage" />
     //          </a>
     //          <div id="lightboxDetails">
     //               <div id="lightboxCaption"></div>
     //               <div id="keyboardMsg"></div>
     //          </div>
     // </div>
     
     var objBody = document.getElementsByTagName("body").item(0);
     
     // create overlay div and hardcode some functional styles (aesthetic styles are in CSS file)
     var objOverlay = document.createElement("div");
     objOverlay.setAttribute('id','overlay');
     objOverlay.onclick = function () {hideLightbox(); return false;}
     objOverlay.style.display = 'none';
     objOverlay.style.position = 'absolute';
     objOverlay.style.top = '0';
     objOverlay.style.left = '0';
     objOverlay.style.zIndex = '90';
      objOverlay.style.width = '100%';
     objBody.insertBefore(objOverlay, objBody.firstChild);
     
     var arrayPageSize = getPageSize();
     var arrayPageScroll = getPageScroll();

     // preload and create loader image
     var imgPreloader = new Image();
     
     // if loader image found, create link to hide lightbox and create loadingimage
     imgPreloader.onload=function(){

          var objLoadingImageLink = document.createElement("a");
          objLoadingImageLink.setAttribute('href','#');
          objLoadingImageLink.onclick = function () {hideLightbox(); return false;}
          objOverlay.appendChild(objLoadingImageLink);
          
          var objLoadingImage = document.createElement("img");
          objLoadingImage.src = loadingImage;
          objLoadingImage.setAttribute('id','loadingImage');
          objLoadingImage.style.position = 'absolute';
          objLoadingImage.style.zIndex = '150';
          objLoadingImageLink.appendChild(objLoadingImage);

          imgPreloader.onload=function(){};     //     clear onLoad, as IE will flip out w/animated gifs

          return false;
     }

     imgPreloader.src = loadingImage;

     // create lightbox div, same note about styles as above
     var objLightbox = document.createElement("div");
     objLightbox.setAttribute('id','lightbox');
     objLightbox.style.display = 'none';
     objLightbox.style.position = 'absolute';
     objLightbox.style.zIndex = '100';     
     objBody.insertBefore(objLightbox, objOverlay.nextSibling);
     
     // create link
     var objLink = document.createElement("a");
     objLink.setAttribute('href','#');
     objLink.setAttribute('title','Kliknij aby zamkn±æ');
     objLink.onclick = function () {hideLightbox(); return false;}
     objLightbox.appendChild(objLink);

     // preload and create close button image
     var imgPreloadCloseButton = new Image();

     // if close button image found, 
     imgPreloadCloseButton.onload=function(){

          var objCloseButton = document.createElement("img");
          objCloseButton.src = closeButton;
          objCloseButton.setAttribute('id','closeButton');
          objCloseButton.style.position = 'absolute';
          objCloseButton.style.zIndex = '200';
          objLink.appendChild(objCloseButton);

          return false;
     }

     imgPreloadCloseButton.src = closeButton;

     // create image
     var objImage = document.createElement("img");
     objImage.setAttribute('id','lightboxImage');
     objLink.appendChild(objImage);
     
     // create details div, a container for the caption and keyboard message
     var objLightboxDetails = document.createElement("div");
     objLightboxDetails.setAttribute('id','lightboxDetails');
     objLightbox.appendChild(objLightboxDetails);

     // create caption
     var objCaption = document.createElement("div");
     objCaption.setAttribute('id','lightboxCaption');
     objCaption.style.display = 'none';
     objLightboxDetails.appendChild(objCaption);

     // create keyboard message
     var objKeyboardMsg = document.createElement("div");
     objKeyboardMsg.setAttribute('id','keyboardMsg');
     objKeyboardMsg.innerHTML = 'kliknij <kbd>x</kbd> aby zamkn±æ';
     objLightboxDetails.appendChild(objKeyboardMsg);


}




//
// addLoadEvent()
// Adds event to window.onload without overwriting currently assigned onload functions.
// Function found at Simon Willison's weblog - http://simon.incutio.com/
//
function addLoadEvent(func)
{     
     var oldonload = window.onload;
     if (typeof window.onload != 'function'){
         window.onload = func;
     } else {
          window.onload = function(){
          oldonload();
          func();
          }
     }

}



addLoadEvent(initLightbox);     // run initLightbox onLoad