// -------------------------------------------------------------------
// Image Thumbnail Viewer Script- By Dynamic Drive, available at: http://www.dynamicdrive.com
// Last updated: July 7th, 2008- Fixed enlarged image not showing in IE sometimes
// -------------------------------------------------------------------

  var thumbnailviewer={
    enableTitle: false, //Should "title" attribute of link be used as description?
    enableAnimation: true, //Enable fading animation?
    definefooter: '<div class="footerbar">CLOSE X</div>', //Define HTML for footer interface
    defineLoading: '<img src="loading.gif" /> Loading Image...', //Define HTML for "loading" div

//var mouseX, mouseY;

    /////////////No need to edit beyond here/////////////////////////
    scrollbarwidth: 16,
    opacitystring: 'filter:progid:DXImageTransform.Microsoft.alpha(opacity=10); -moz-opacity: 0.1; opacity: 0.1',
    targetlinks:[], //Array to hold links with rel="thumbnail"

    createthumbBox:function(){
      //write out HTML for Image Thumbnail Viewer plus loading div
      document.write('<div id="thumbBox" onClick="thumbnailviewer.closeit()"><div id="thumbImage"></div>'+this.definefooter+'</div>')
      document.write('<div id="thumbLoading">'+this.defineLoading+'</div>')
      this.thumbBox=document.getElementById("thumbBox")
      this.thumbImage=document.getElementById("thumbImage") //Reference div that holds the shown image
      this.thumbLoading=document.getElementById("thumbLoading") //Reference "loading" div that will be shown while image is fetched
      this.standardbody=(document.compatMode=="CSS1Compat")? document.documentElement : document.body //create reference to common "body" across doctypes
    },

    centerDiv:function(divobj) { //Centers a div element on the page
      var ie=document.all && !window.opera
      var dom=document.getElementById
      var scroll_top=(ie)? this.standardbody.scrollTop : window.pageYOffset
      var scroll_left=(ie)? this.standardbody.scrollLeft : window.pageXOffset
      var docwidth=(ie)? this.standardbody.clientWidth : window.innerWidth-this.scrollbarwidth
      var docheight=(ie)? this.standardbody.clientHeight: window.innerHeight
      var docheightcomplete=(this.standardbody.offsetHeight>this.standardbody.scrollHeight)? this.standardbody.offsetHeight : this.standardbody.scrollHeight //Full scroll height of document
      var objwidth=divobj.offsetWidth //width of div element
      var objheight=divobj.offsetHeight //height of div element
      //Vertical position of div element: Either centered, or if element height larger than viewpoint height, 10px from top of viewpoint
      //var topposition=(docheight>objheight)? scroll_top+docheight/2-objheight/2+"px" : scroll_top+10+"px" 
      var topposition=(ie)?scroll_top + window.event.clientY-objheight/2 +"px":
                          (docheight>objheight)? scroll_top+docheight/2-objheight/2+"px" : scroll_top+10+"px"  //Vertical position of div element: Either centered, or if element height larger than viewpoint height, 10px from top of viewpoint
      //divobj.style.left=docwidth/2-objwidth/2+"px" //Center div element horizontally
      divobj.style.left=docwidth/2-437+"px" //Left adjust div element horizontally
      divobj.style.top=Math.floor(parseInt(topposition))+"px"
      divobj.style.visibility="visible"
      divobj.setAttribute('title','Click to close');
    },

    showthumbBox:function(){ //Show ThumbBox div
      thumbnailviewer.thumbLoading.style.visibility="hidden" //Hide "loading" div
      this.centerDiv(this.thumbBox)
      if (this.enableAnimation){ //If fading animation enabled
        this.currentopacity=0.1 //Starting opacity value
        this.opacitytimer=setInterval("thumbnailviewer.opacityanimation()", 20)
      }
    },


    loadimage:function(link){ //Load image function that gets attached to each link on the page with rel="thumbnail"
      if (this.thumbBox.style.visibility=="visible") //if thumbox is visible on the page already
      this.closeit() //Hide it first (not doing so causes triggers some positioning bug in Firefox
      var imageHTML='<img src="'+link.getAttribute("href")+'" style="'+this.opacitystring+'" />' //Construct HTML for shown image
      if (this.enableTitle && link.getAttribute("title")) //Use title attr of the link as description?
        imageHTML+='<br />'+link.getAttribute("title")
      this.centerDiv(this.thumbLoading) //Center and display "loading" div while we set up the image to be shown
      this.thumbImage.innerHTML=imageHTML //Populate thumbImage div with shown image's HTML (while still hidden)
      this.featureImage=this.thumbImage.getElementsByTagName("img")[0] //Reference shown image itself
      if (this.featureImage.complete) thumbnailviewer.showthumbBox()
      else{
        this.featureImage.onload=function(){ //When target image has completely loaded
          thumbnailviewer.showthumbBox() //Display "thumbbox" div to the world!
        }
      }
      if (document.all && !window.createPopup) //Target IE5.0 browsers only. Address IE image cache not firing onload bug: panoramio.com/blog/onload-event/
        this.featureImage.src=link.getAttribute("href")
      this.featureImage.onerror=function() { //If an error has occurred while loading the image to show
        thumbnailviewer.thumbLoading.style.visibility="hidden" //Hide "loading" div, game over
      }
    },

    setimgopacity:function(value){ //Sets the opacity of "thumbimage" div per the passed in value setting (0 to 1 and in between)
      var targetobject=this.featureImage
      if (targetobject.filters && targetobject.filters[0]){ //IE syntax
        if (typeof targetobject.filters[0].opacity=="number") //IE6
          targetobject.filters[0].opacity=value*100
        else //IE 5.5
        targetobject.style.filter="alpha(opacity="+value*100+")"
      } else if (typeof targetobject.style.MozOpacity!="undefined") //Old Mozilla syntax
          targetobject.style.MozOpacity=value
      else if (typeof targetobject.style.opacity!="undefined") //Standard opacity syntax
        targetobject.style.opacity=value
      else //Non of the above, stop opacity animation
        this.stopanimation()
    },

    opacityanimation:function() { //Gradually increase opacity function
      this.setimgopacity(this.currentopacity)
      this.currentopacity+=0.1
      if (this.currentopacity>1) this.stopanimation()
    },
  
    stopanimation:function() {
      if (typeof this.opacitytimer!="undefined")
        clearInterval(this.opacitytimer)
    },


    closeit:function(){ //Close "thumbbox" div function
      this.stopanimation()
      this.thumbBox.style.visibility="hidden"
      this.thumbImage.innerHTML=""
      this.thumbBox.style.left="-2000px"
      this.thumbBox.style.top="-2000px"
    },

    cleanup:function(){ //Clean up routine on page unload
      this.thumbLoading=null
      if (this.featureImage) this.featureImage.onload=null
        this.featureImage=null
      this.thumbImage=null
      for (var i=0; i<this.targetlinks.length; i++)
        this.targetlinks[i].onclick=null
      this.thumbBox=null
    },

    dotask:function(target, functionref, tasktype) { //assign a function to execute to an event handler (ie: onunload)
      var tasktype=(window.addEventListener)? tasktype : "on"+tasktype
      if (target.addEventListener) 
        target.addEventListener(tasktype, functionref, false)
      else if (target.attachEvent)
        target.attachEvent(tasktype, functionref)
    },

    init:function(){ //Initialize thumbnail viewer script by scanning page and attaching appropriate function to links with rel="thumbnail"
      if (!this.enableAnimation) this.opacitystring=""
      var pagelinks=document.getElementsByTagName("a")
      for (var i=0; i<pagelinks.length; i++) { //BEGIN FOR LOOP
        if (pagelinks[i].getAttribute("rel") && pagelinks[i].getAttribute("rel")=="thumbnail") { //Begin if statement
          pagelinks[i].onclick=function(e) {
            thumbnailviewer.stopanimation() //Stop any currently running fade animation on "thumbbox" div before proceeding
            thumbnailviewer.loadimage(this) //Load image
            return false
          }
          this.targetlinks[this.targetlinks.length]=pagelinks[i] //store reference to target link
        } //end if statement
      } //END FOR LOOP
      //Reposition "thumbbox" div when page is resized
      this.dotask(window, function(){
        if (thumbnailviewer.thumbBox.style.visibility=="visible") 
          thumbnailviewer.centerDiv(thumbnailviewer.thumbBox)}, "resize")
    } //END init() function
  }



thumbnailviewer.createthumbBox() //Output HTML for the image thumbnail viewer
thumbnailviewer.dotask(window, function(){thumbnailviewer.init()}, "load") //Initialize script on page load
thumbnailviewer.dotask(window, function(){thumbnailviewer.cleanup()}, "unload")