// -- Common Javascript for Technology Specialists Website
// Copyright (c) 2003 Technology Specialists, All Rights Reserved.
// Written by Donn Bly, 26 June 2003
// Updated by Donn Bly, 02 Auguest 2003
//    .  Updated for object detection to avoid problems with very old browsers.

function img_load() {
// Scan IMG tags on page looking for names beginning with "btn_", if any are found, preload the hover images
   if (document.body && document.GetElementsByTagName) {
      img_preload = new Object();
      var img_list;
      var i;
      var img_name;
      var img_hover;
      var img_src;
      var img_ext;

      img_list=document.getElementsByTagName('img');
      for(i=0; i<img_list.length; i++){
         img_name = img_list[i].name;
         img_src = img_list[i].src;
         if ((img_name.indexOf('btn_')==0) && (img_src.lastIndexOf('.')>0)) {
            img_ext = img_src.slice(img_src.lastIndexOf('.',img_src.length),img_src.length);
            img_hover = '/images/' + img_name.slice(4,img_name.length) + '_hover' + img_ext;
            img_preload[i] = new Image();
            img_preload[i].src = img_hover;
         }
      }
   }
}

function img_hover(imgtag) {
// load hover image
   if (document.images) {
      var img_name = imgtag.name;
      var img_src = imgtag.src;
      if ((img_name.indexOf('btn_')==0) && (img_src.lastIndexOf('.')>0)) {
         var img_ext = img_src.slice(img_src.lastIndexOf('.',img_src.length),img_src.length);
         imgtag.src = '/images/' + img_name.slice(4,img_name.length) + '_hover' + img_ext;
      }
   }
}

function img_restore(imgtag) {
// restore normal image
   if (document.images) {
      var img_name = imgtag.name;
      var img_src = imgtag.src;
      if ((img_name.indexOf('btn_')==0) && (img_src.lastIndexOf('.')>0)) {
         var img_ext = img_src.slice(img_src.lastIndexOf('.',img_src.length),img_src.length);
         imgtag.src = '/images/' + img_name.slice(4,img_name.length) + '_button' + img_ext;
      }
   }
}