/**
 * This one displays nice preloader instead of thumbnails
 */
function preloader_start() {
  if (document.getElementsByTagName) {
    var anchors = document.getElementsByTagName('a');
    for (var i=0; i<anchors.length; i++) {
      var anchor = anchors[i];
      var relAttribute = String(anchor.getAttribute('rel'));
      if (relAttribute.toLowerCase().match('thickbox_')) {
        img = anchor.getElementsByTagName('img')[0];
        img.style.display = 'none';
        box = document.createElement('div');
        box.className = 'tb_preloaderBox';
        ldr = document.createElement('div');
        ldr.className = 'tb_preloaderImg';
        box.appendChild(ldr);
        anchor.style.textDecoration = 'none';
        anchor.appendChild(box);
      }
    }
  }
}

/**
 * This one cleans preloader and displays thumbnails
 */
function preloader_clean() {
  if (document.getElementsByTagName) {
    var anchors = document.getElementsByTagName('a');
    for (var i=0; i<anchors.length; i++) {
      var anchor = anchors[i];
      var relAttribute = String(anchor.getAttribute('rel'));
      if (relAttribute.toLowerCase().match('thickbox_')) {
        img = anchor.getElementsByTagName('img')[0];
        box = anchor.getElementsByTagName('div')[0];
        if (box !== undefined) {
          box.removeChild(box.firstChild);
          box.parentNode.removeChild(box);
        }
        img.style.display = 'inline';
      }
    }
  }
}