TimeHelper::getUserToServerOffset

public function getUserToServerOffset($userId = null)
{
	$userId = ($userId === null ? -1 : (int) $userId);

	$cacheTtl = (defined('BX_COMP_MANAGED_CACHE') ? 3153600 : 3600 * 24);
	$cacheId = 'time_zone_'.$userId;
	$cacheDir = '/timeman/timezone/'.substr(md5($userId), -2).'/'.$userId;

	$cache = new CPHPCache;
	if ($cache->initCache($cacheTtl, $cacheId, $cacheDir))
	{
		$this->timezoneOffsets[$userId] = $cache->getVars();
	}
	else
	{
		global $CACHE_MANAGER;

		$cache->startDataCache();

		$CACHE_MANAGER->startTagCache($cacheDir);

		$this->timezoneOffsets[$userId] = (int) CTimeZone::getOffset($userId, true);

		$CACHE_MANAGER->registerTag('USER_NAME_'. $userId);
		$CACHE_MANAGER->endTagCache();

		$cache->endDataCache($this->timezoneOffsets[$userId]);
	}

	return $this->timezoneOffsets[$userId];
}