var imagenr = 0;
var images = new Array();

function imageDone() {
 document.body.style.cursor = 'default';
}

function showImage(filename, nodeid,  desc, name) {
 var image = document.getElementById('showing');
 document.getElementById('image' + nodeid).className = 'activeimg';
 document.getElementById('image' + activeimg).className = 'inactiveimg';
 activeimg = nodeid;
 image.src = '/images/' + filename; 
 image.onload = imageDone;
 document.getElementById('imagealt').innerHTML = desc;
 document.getElementById('imagename').innerHTML = name;
 document.body.style.cursor = 'wait';
}

function imageObject(filename, nodeid, description, name) {
 this.filename = filename;
 this.nodeid = nodeid;
 this.description = description;
 this.name = name;
}

function findCurrent() {
 var a = 0;
 var found = -1;
 while (found < 0 || a > 10000) {
  if (images[a].nodeid == activeimg) {found = a;}
  a++;
 }
 return a-1;
}

function nextImg() {
 var current = findCurrent();
 if (current == images.length-1) {current = 0;} 
  else {current++;}
 showImage(images[current].filename, images[current].nodeid ,images[current].description, images[current].name);
}

function prevImg() {
 var current = findCurrent();
 if (current == 0) {current = images.length -1;}
 else {current--;}
 showImage(images[current].filename, images[current].nodeid,images[current].description,images[current].name);
}