function format_name($username, $usergroup, $displaygroup="")
{
	global $db;
	$query = $db->query("SELECT fid5 FROM ".TABLE_PREFIX."userfields f LEFT JOIN ".TABLE_PREFIX."users u ON u.uid = f.uid WHERE u.username = '".$db->escape_string($username)."'");
	
	if(!strpos($format = $db->fetch_field($query, 'fid5'), '{username}'))
	{
		global $groupscache, $cache;

		if(!is_array($groupscache))
			$groupscache = $cache->read("usergroups");

		if($displaygroup) $usergroup = $displaygroup;
		
		if(!strpos(($format = $groupscache[$usergroup]['namestyle']), '{username}'))
			$format = "{username}";
	}
	return str_replace("{username}", $username, stripslashes($format));
}