/**
 * jQuery Lightbox
 * Version 0.5 - 11/29/2007
 * @author Warren Krewenki
 *
 * This package is distributed under the BSD license.
 * For full license information, see LICENSE.TXT
 *
 * 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($) {
   $.fn.lightbox = function(options) {
      // build main options
      var opts = $.extend({}, $.fn.lightbox.defaults, options);
        
      return $(this).live("click",function(){
         // initialize the lightbox
         initialize();
         start(this);
         return false;
      });
      
    /**
     * initalize()
     *
     * @return void
     * @author Warren Krewenki
     */
    function initialize() {
       $('#overlay').remove();
       $('#lightbox').remove();
       opts.inprogress = false;
    
       // if jsonData, build the imageArray from data provided in JSON format
      if (opts.jsonData && opts.jsonData.length > 0) {
         var parser = opts.jsonDataParser ? opts.jsonDataParser : $.fn.lightbox.parseJsonData;                
         opts.imageArray = [];
         opts.imageArray = parser(opts.jsonData);
      }
    
       var outerImage = '<div id="outerImageContainer"><div id="imageContainer"><iframe id="lightboxIframe" /><img id="lightboxImage"><div id="hoverNav"><a href="javascript://" title="' + opts.strings.prevLinkTitle + '" id="prevLink"></a><a href="javascript://" id="nextLink" title="' + opts.strings.nextLinkTitle + '"></a></div><div id="loading"><a href="javascript://" id="loadingLink"><img src="'+opts.fileLoadingImage+'"></a></div></div></div>';
       var imageData = '<div id="imageDataContainer" class="clearfix"><div id="imageData"><div id="imageDetails"><span id="caption"></span><span id="numberDisplay"></span></div><div id="bottomNav">';

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

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

       var string;

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

       if (!opts.imageClickClose) {
            $("#lightboxImage").click(function(){ return false; });
            $("#hoverNav").click(function(){ return false; });
       }
    };
       
    function getPageSize() {
       var jqueryPageSize = new Array($(document).width(),$(document).height(), $(window).width(), $(window).height());
       return jqueryPageSize;
    };
       
    function getPageScroll() {
       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;
       }

       var arrayPageScroll = new Array(xScroll,yScroll);
       return arrayPageScroll;
    };
       
    function pause(ms) {
       var date = new Date();
       var curDate = null;
       do{curDate = new Date();}
       while(curDate - date < ms);
    };
       
    function start(imageLink) {
       $("select, embed, object").hide();
       var arrayPageSize = getPageSize();
       $("#overlay").hide().css({
            width: '100%', 
            height: arrayPageSize[1] + 'px', 
            opacity : opts.overlayOpacity
         }).fadeIn();
       imageNum = 0;

       // if data is not provided by jsonData parameter
      if (!opts.jsonData) {
         opts.imageArray = [];
         // if image is NOT part of a set..
         if ((!imageLink.rel || (imageLink.rel == '')) && !opts.allSet) {
             // add single image to Lightbox.imageArray
             opts.imageArray.push(new Array(imageLink.href, opts.displayTitle ? imageLink.title : ''));
         } else {
            // if image is part of a set..
             $("a").each(
                  function() {
                 if(this.href && (this.rel == imageLink.rel)) {
                    opts.imageArray.push(new Array(this.href, opts.displayTitle ? this.title : ''));
                 }
                }
               );
         }
       }
   
       if (opts.imageArray.length > 1) {
        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 = getPageScroll();
       var lightboxTop = arrayPageScroll[1] + (arrayPageSize[3] / 10);
       var lightboxLeft = arrayPageScroll[0];
       $('#lightbox').css({top: lightboxTop+'px', left: lightboxLeft+'px'}).show();


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

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

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

            // delay preloading image until navbar will slide up
          if (opts.slideNavBar) { 
             $('#imageDataContainer').hide();
             $('#imageData').hide();
             doChangeImage();
          } else {
             doChangeImage();
          }
       }
    };
       
     function doChangeImage() {
       imgPreloader = new Image();

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

            if (opts.scaleImages) {
               newWidth = parseInt(opts.xScale * newWidth);
               newHeight = parseInt(opts.yScale * newHeight);
            }

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

               var dI = initialPageWidth/initialPageHeight;
               var dP = imgPreloader.width/imgPreloader.height;

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

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

        imgPreloader.src = opts.imageArray[opts.activeImage][0];
      };
       
   function end() {
      disableKeyboardNav();
      $('#lightbox').hide();
      $('#overlay').fadeOut();
      $('select, object, embed').show();
   };
       
    function preloadNeighborImages() {
       if (opts.loopImages && opts.imageArray.length > 1) {
         preloadNextImage = new Image();
         preloadNextImage.src = opts.imageArray[(opts.activeImage == (opts.imageArray.length - 1)) ? 0 : opts.activeImage + 1][0]
      
         preloadPrevImage = new Image();
         preloadPrevImage.src = opts.imageArray[(opts.activeImage == 0) ? (opts.imageArray.length - 1) : opts.activeImage - 1][0]
         } else {
            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];
            }
         }
    };
       
    function resizeImageContainer(imgWidth, imgHeight) {
         // get current width and height
         opts.widthCurrent = $("#outerImageContainer").outerWidth();
         opts.heightCurrent = $("#outerImageContainer").outerHeight();
   
         // get new width and height
         var widthNew = Math.max(350, imgWidth  + (opts.borderSize * 2));
         var heightNew = (imgHeight  + (opts.borderSize * 2));

         // 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() {
               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)) {
            if (jQuery.browser.msie) { 
               pause(250); 
            } else { 
               pause(100);
            }
         }

         $('#prevLink').height(imgHeight);
         $('#nextLink').height(imgHeight);
    };
       
    function showImage() {
       $('#loading').hide();
       $('#lightboxImage').fadeIn("fast");
       updateDetails();
       preloadNeighborImages();

       opts.inprogress = false;
    };
       
      function updateDetails() {
         $('#numberDisplay').html('');

         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;

            nav_html = opts.strings.image + (opts.activeImage + 1) + opts.strings.of + opts.imageArray.length;
            
            if (opts.displayDownloadLink) {
               nav_html += "<a href='" + opts.imageArray[opts.activeImage][0] + "'>" + opts.strings.download + "</a>";
            }            

            if (!opts.disableNavbarLinks) {
               // display previous / next text links
               if ((opts.activeImage) > 0 || opts.loopImages) {
                  nav_html = '<a title="' + opts.strings.prevLinkTitle + '" href="#" id="prevLinkText">' + opts.strings.prevLinkText + "</a>" + nav_html;
               }

               if (((opts.activeImage + 1) < opts.imageArray.length) || opts.loopImages) {
                  nav_html += '<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 = getPageSize();
         $('#overlay').height(arrayPageSize[1]);
         updateNav();
      };
       
    function updateNav() {
       if (opts.imageArray.length > 1) {
          $('#hoverNav').show();
                
            // if loopImages is true, always show next and prev image buttons 
            if(opts.loopImages) {
               $('#prevLink,#prevLinkText').show().click(function() {
                  changeImage((opts.activeImage == 0) ? (opts.imageArray.length - 1) : opts.activeImage - 1); 
                  return false;
               });

               $('#nextLink,#nextLinkText').show().click(function() {
                  changeImage((opts.activeImage == (opts.imageArray.length - 1)) ? 0 : opts.activeImage + 1); 
                  return false;
               });
              
            } else {
               // if not first image in set, display prev image button
               if(opts.activeImage != 0) {
                  $('#prevLink,#prevLinkText').show().click(function() {
                     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() {
                     changeImage(opts.activeImage +1); 
                     return false;
                  });
               }
            }
               
          enableKeyboardNav();
       }
    };
       
      function keyboardAction(e) {
         var o = e.data.opts
         var keycode = e.keyCode;
         var escapeKey = 27;

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

         // close lightbox
         if ((key == 'x') || (key == 'o') || (key == 'c') || (keycode == escapeKey)) { 
            end();
            
         // display previous image   
         } else if ((key == 'p') || (keycode == 37)) {  
            if(o.loopImages) {
               disableKeyboardNav();
               changeImage((o.activeImage == 0) ? (o.imageArray.length - 1) : o.activeImage - 1);
            } 
            else if (o.activeImage != 0) {
               disableKeyboardNav();
               changeImage(o.activeImage - 1);
            }
            
         // display next image
         } else if ((key == 'n') || (keycode == 39)) { 
            if (opts.loopImages) {
               disableKeyboardNav();
               changeImage((o.activeImage == (o.imageArray.length - 1)) ? 0 : o.activeImage + 1);
            }
            else if (o.activeImage != (o.imageArray.length - 1)) {
               disableKeyboardNav();
               changeImage(o.activeImage + 1);
            }
         }
      };
       
      function enableKeyboardNav() {
         $(document).bind('keydown', {opts: opts}, keyboardAction);
      };

      function disableKeyboardNav() {
         $(document).unbind('keydown');
      };       
   };
    
   $.fn.lightbox.parseJsonData = function(data) {
      var imageArray = [];

      $.each(data, function() {
         imageArray.push(new Array(this.url, this.title));
      });

      return imageArray;
   };

   $.fn.lightbox.defaults = {
      allSet: false,
      fileLoadingImage: '/images/loading.gif',
      fileBottomNavCloseImage: '/images/closelabel.gif',
      overlayOpacity: 0.8,
      borderSize: 10,
      imageArray: new Array,
      activeImage: null,
      inprogress: false,
      resizeSpeed: 350,
      widthCurrent: 250,
      heightCurrent: 250,
      scaleImages: false,
      xScale: 1,
      yScale: 1,
      displayTitle: true,
      navbarOnTop: false,
      displayDownloadLink: false,
      
      // slide nav bar up/down between image resizing transitions
      slideNavBar: false, 
      
      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 ',
         download: 'Download'
      },
      
      // resize images if they are bigger than window
      fitToScreen: false,      
      
    disableNavbarLinks: false,
    loopImages: false,
    imageClickClose: true,
    jsonData: null,
    jsonDataParser: null
   };   
})(jQuery);