/**
 * 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);