/* Table Of Contents Script "toc"
 * developed by Sergio Morozov, July 1997.
 * Special thanks to www.jtricks.com for an idea.
 */

var selectedItem = undefined;


function isAncestor( ofItem, pItem)
{
  var res = false;
  var curItem = ofItem;
  
  for( ; !(res = curItem == pItem) && curItem != null; curItem = curItem.parentNode) ;
  return res;
}

function commonAncestor( item1, item2)
{
  var res = item1;
  
  for( res; 
    !isAncestor( item2, res) && res != undefined && res != null; 
    res = res.parentNode);
  return res;
}

function selectItem( itemID)
{
  var item =  document.getElementById(itemID);
  if ( item.style.display == 'none' ) 
  {
    if( selectedItem != undefined && !isAncestor( item, selectedItem))
    {
      var ancestor = commonAncestor( selectedItem, item);
      var curItem = selectedItem;
      
      for( ; curItem != ancestor && curItem != null; curItem = curItem.parentNode) 
        curItem.style.display='none';
    }			
    item.style.display='' ;
    selectedItem = item;
  }
  else 
    item.style.display='none' ;
}

function toggleItem( itemID)
{
  var item =  document.getElementById(itemID);
  if ( item.style.display == 'none' ) item.style.display='' ;
  else item.style.display='none' ;
}

function toggleItems( itemIDs)
{
	for( var i = 0; i < itemIDs.length; i++)
		toggleItem( itemIDs[i]);
}