// -------------------------------------------------------------------
// Image Thumbnail Viewer Script- By Dynamic Drive, available at: http://www.dynamicdrive.com
// Last updated: Jan 22nd, 2007
// -------------------------------------------------------------------

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

    // Write out HTML for Image Thumbnail Viewer plus loading div
    createthumbBox:function()
    {
        //2009: document.write('<div id="thumbBox" onMouseOut="thumbnailviewer.closeit()" onClick="thumbnailviewer.closeit()"><div id="thumbImage"></div>' + this.definefooter + '</div>')
				//Dus de thumbBox sluit als je de rand passeert. beter is:				
		    document.write('<div id="thumbBox" onClick="thumbnailviewer.closeit()"><div id="thumbImage" onMouseOut="thumbnailviewer.closeit()"></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
    },
    
    // Centers a div element on the page
    centerDiv:function(divobj)
    {
        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
        var topposition = (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 = 10 + "px"       // david: a bit on the left
        divobj.style.top = Math.floor(parseInt(topposition)) + "px"
        divobj.style.visibility = "visible"
    },
    
    // Show ThumbBox div
    showthumbBox:function()
    {
        this.centerDiv(this.thumbBox)
        if(this.enableAnimation)
        {
            //If fading animation enabled
            this.currentopacity = 0.1                                //Starting opacity value
            this.opacitytimer = setInterval("thumbnailviewer.opacityanimation()", 20)
        }
    },
    
    // Load image function that gets attached to each link on the page with rel="thumbnail"
    loadimage:function(link)
    {
        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
        this.featureImage.onload = function()
        {
            // When target image has completely loaded
            thumbnailviewer.thumbLoading.style.visibility = "hidden" // Hide "loading" div
            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
        }
    },
    
    // Sets the opacity of "thumbimage" div per the passed in value setting (0 to 1 and in between)
    setimgopacity:function(value)
    {
        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                                                         // None of the above, stop opacity animation
            this.stopanimation()
    },
    
    // Gradually increase opacity function
    opacityanimation: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)
    },
    
    // Close "thumbbox" div function
    closeit:function()
    {
        this.stopanimation()
        this.thumbBox.style.visibility = "hidden"
        this.thumbImage.innerHTML = ""
        this.thumbBox.style.left = "-2000px"
        this.thumbBox.style.top = "-2000px"
    },
    
    // Clean up routine on page unload
    cleanup:function()
    {
        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
    },
    
    // Assign a function to execute to an event handler (ie: onunload)
    dotask:function(target, functionref, tasktype)
    {
        var tasktype = (window.addEventListener) ? tasktype : "on" + tasktype
        if(target.addEventListener)
            target.addEventListener(tasktype, functionref, false)
        else if(target.attachEvent)
            target.attachEvent(tasktype, functionref)
    },
    
    // Initialize thumbnail viewer script by scanning page and attaching appropriate function to links with rel="thumbnail"
    init:function()
    {
        if(!this.enableAnimation)
            this.opacitystring = ""
        var pagelinks = document.getElementsByTagName("a")
        for(var i = 0; i < pagelinks.length; i++)
        {
            if(pagelinks[i].getAttribute("rel") && pagelinks[i].getAttribute("rel") == "thumbnail")
            {
                pagelinks[i].onclick = function()
                {
                    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
            }
        }
        //Reposition "thumbbox" div when page is resized
        this.dotask(window, function()
        {
            if(thumbnailviewer.thumbBox.style.visibility == "visible")
                thumbnailviewer.centerDiv(thumbnailviewer.thumbBox)
        }, "resize")
    }
}

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")