function parent_spec_change()
{
	var select_obj = document.getElementById( "parent_spec" );
	if ( select_obj )
	{
		var sel_index = select_obj.selectedIndex;
		if ( sel_index >= 0 )
		{
			var curr_pb_id = select_obj.options[sel_index].value;
			var len = select_obj.options.length;
			for ( i = 0; i < len; i++ )
			{
				var pb_id = select_obj.options[i].value;
				var block_name = "spec_block_" + pb_id;
				var pb = document.getElementById( block_name );
				if ( pb_id > 0 )
				{
					if ( pb )
					{
						if ( pb_id == curr_pb_id )
						{
							pb.className = "spec_block";
							new Effect.Highlight(block_name,{ startcolor: '#e1e1e1',
endcolor: '#ffffff' });
							//pb.className = "spec_block";
						}
						else
						{
							pb.className = "spec_block_hidden";
							check_all( block_name, false );
						}
					}
					else
					{
						alert( "Block " + i + " not found." );
					}
				}
			}
		}
	}
	else
	{
		alert( "ERROR: Select object not found." );
	}
	checkCost();
}

function check_all( block_name, flag )
{
	var block_obj = document.getElementById( block_name );
	if ( block_obj )
	{
		var len = block_obj.childNodes.length;
		for ( var i = 0; i < len; i++ )
		{
			if ( block_obj.childNodes[i].tagName == 'LABEL' )
			{
				check_box( block_obj.childNodes[i], flag );
			}
		}
	}
	else
	{
		alert( 'Block object not found' );
	}

	return false;
}

function check_box( obj, flag )
{
	var len = obj.childNodes.length;
	for ( var i = 0; i < len; i++ )
	{
		if ( obj.childNodes[i].tagName == 'INPUT' )
		{
			obj.childNodes[i].checked = flag;
		}
	}
}

function goPage( page )
{
	var form_name = "spec_search_form";
	var form_obj = document.getElementById( form_name );
	if ( form_obj )
	{
		var page_obj = document.getElementById( "page_num" );
		if ( page_obj )
		{
			page_obj.value = page;
			form_obj.submit();
		}
		else
		{
			alert( "Form element 'page_num' not found" );
		}
	}
	else
	{
		alert( "Form " + form_name + " not found" );
	}
	return false;
}

function checkCost()
{
	var parent_spec = document.getElementById( "parent_spec" );
	if ( !parent_spec )
	{
		alert( "Element 'parent_spec' not found" );
		return;
	}
	
	var cost = document.getElementById( 'cost' );
	if ( !cost )
	{
		alert( "Element 'cost' not found" );
		return;
	}

	if ( parent_spec.options[parent_spec.selectedIndex].value > 0 )
	{
		cost.disabled = false;
	}
	else
	{
		cost.disabled = true;
	}
}