/**
 * Formats a username based on their display group
 *
 * @param string The username
 * @param int The usergroup for the user (if not specified, will be fetched)
 * @param int The display group for the user (if not specified, will be fetched)
 * @return string The formatted username
 */
function format_name($username, $usergroup, $displaygroup="")
{
	global $groupscache, $cache;

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

	if($displaygroup != 0)
	{
		$usergroup = $displaygroup;
	}

	$ugroup = $groupscache[$usergroup];
	$format = $ugroup['namestyle'];
	$userin = substr_count($format, "{username}");

	if($userin == 0)
	{
		$format = "{username}";
	}

	$format = stripslashes($format);

	return str_replace("{username}", $username, $format);
}