var image_slideshow_index = 1;
function image_slideshow(direction)
{
  if(direction == 'next')
  {
    //alert(image_slideshow_index+ ' '+(image_slideshow_index+1));
    //document.getElementById('image_slideshow_'+(image_slideshow_index+1)).style.display = 'block';
    if(document.getElementById('image_slideshow_'+(image_slideshow_index+1)))
    {
      
      document.getElementById('image_slideshow_'+image_slideshow_index).style.display = 'none';
      document.getElementById('link_slideshow_'+image_slideshow_index).style.fontWeight = 'normal';
      image_slideshow_index = (image_slideshow_index+1);
      document.getElementById('image_slideshow_'+image_slideshow_index).style.display = 'block';
      document.getElementById('link_slideshow_'+image_slideshow_index).style.fontWeight = 'bold';
    }
  }
  else if(direction == 'prev')
  {
    if(document.getElementById('image_slideshow_'+(image_slideshow_index-1)))
    {
      document.getElementById('image_slideshow_'+image_slideshow_index).style.display = 'none';
      document.getElementById('link_slideshow_'+image_slideshow_index).style.fontWeight = 'normal';
      image_slideshow_index = (image_slideshow_index-1);
      document.getElementById('image_slideshow_'+image_slideshow_index).style.display = 'block';
      document.getElementById('link_slideshow_'+image_slideshow_index).style.fontWeight = 'bold';
    }
  }
  else
  {
    if(document.getElementById('image_slideshow_'+parseInt(direction)))
    {
      document.getElementById('image_slideshow_'+image_slideshow_index).style.display = 'none';
      document.getElementById('link_slideshow_'+image_slideshow_index).style.fontWeight = 'normal';
      image_slideshow_index = parseInt(direction);
      document.getElementById('image_slideshow_'+parseInt(direction)).style.display = 'block';
      document.getElementById('link_slideshow_'+parseInt(direction)).style.fontWeight = 'bold';
    }
  }
}