UserSettings::getFollowedSectionIdList

static function getFollowedSectionIdList($userId = false)
{
	$sectionIdList = [];
	if ($userId)
	{
		$defaultFollowedSectionId = intval(CUserOptions::GetOption("calendar", "superpose_displayed_default", 0, $userId));
		if ($defaultFollowedSectionId)
		{
			$sectionIdList[] = $defaultFollowedSectionId;
		}

		$str = CUserOptions::GetOption("calendar", "superpose_displayed", false, $userId);
		if (CheckSerializedData($str))
		{
			$idList = unserialize($str, ['allowed_classes' => false]);
			if (is_array($idList))
			{
				foreach($idList as $id)
				{
					if (intval($id) > 0)
					{
						$sectionIdList[] = intval($id);
					}
				}
			}
		}

		if ($defaultFollowedSectionId)
		{
			CUserOptions::SetOption("calendar", "superpose_displayed", serialize($sectionIdList));
			CUserOptions::SetOption("calendar", "superpose_displayed_default", false);
		}
	}
	return $sectionIdList;
}