var lastId = 1;
var lastCurrent = 0;

function changeImage(id, src)
{
    lastId = parseInt(id);

    // We gaan alle div elementen ophalen
    e = document.getElementsByTagName("div");
    for(i=0;i < e.length;i++)
    {
        if(e[i].id.match("navImage"))
        {
            if(e[i].id == "navImage" + id)
            {
                e[i].className = 'scrollnav_current';
            } else {
                e[i].className = 'scrollnav';
            }
        }
    }

    setTimeout("checkImageBar()", 100);
    setTimeout("highlight()", 200);

    // We gaan de afbeelding invullen
    document.getElementById('displayImage').src = src;
}

function highlight()
{
    // We gaan alle div elementen ophalen
    e = document.getElementsByTagName("div");
    for(i=0;i < e.length;i++)
    {
        if(e[i].id.match("navImage"))
        {
            if(e[i].id == "navImage" + lastId)
            {
                e[i].className = 'scrollnav_current';
            } else {
                e[i].className = 'scrollnav';
            }
        }
    }
}

function changeToImage(type)
{
    // We gaan kijken welke kant we opgaan
    if(type=='-')
    {
        if((lastId - 1) > 0 && lastId > 6)
        {
            reloadImages((lastCurrent - 1), currentId);
            changeImage((lastId - 1), images[(lastId - 1)]);
        } else if((lastId - 1) > 0) {
            changeImage((lastId - 1), images[(lastId - 1)]);
        }
    } else if(type=='+') {
        if(((lastId + 1) - lastCurrent) > 6 && (lastId + 1) < images.length)
        {
            reloadImages((lastCurrent + 1), currentId);
            changeImage((lastId + 1), images[(lastId + 1)]);
        } else if((lastId + 1) < images.length) {
            changeImage((lastId + 1), images[(lastId + 1)]);
        }
    }
}

function checkImageBar()
{
    if((images.length - 1) == lastId)
    {
        document.getElementById("next").style.display = 'none';
    } else {
        document.getElementById("next").style.display = 'block';
    }

    if(lastId==1)
    {
        document.getElementById("prev").style.display = 'none';
    } else {
        document.getElementById("prev").style.display = 'block';
    }
}

function ajaxinit()
{
	var xmlhttp=false;
	/*@cc_on @*/
	/*@if (@_jscript_version >= 5)
	// JScript gives us Conditional compilation, we can cope with old IE versions.
	// and security blocked creation of the objects.
	 try {
	  xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
	 } catch (e) {
	  try {
	   xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
	  } catch (E) {
	   xmlhttp = false;
	  }
	 }
	@end @*/
	if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
		try {
			xmlhttp = new XMLHttpRequest();
		} catch (e) {
			xmlhttp=false;
		}
	}
	if (!xmlhttp && window.createRequest) {
		try {
			xmlhttp = window.createRequest();
		} catch (e) {
			xmlhttp=false;
		}
	}

  	return xmlhttp;
}

function reloadImages(current, id)
{
    lastCurrent = current;

    // We gaan de afbeeldingen opnieuw laden
    // We gaan de request string maken
    var http = ajaxinit();
    if(http)
    {
        http.open('GET','/index.php?page=product&id=' + id + '&action=info&ajax=1&current=' + current + '&last=' + lastId,true);
        http.onreadystatechange = function() {
            if (http.readyState == 4)
            {
                if (http.status == 200)
                {
                    response = http.responseText;
                    document.getElementById("imagescroller").innerHTML = response;
                } else {
                    alert("There was a problem retrieving the XML data:\n" + http.statusText);
                    return false;
                }
            }
        }
        http.send(null);
    }
}