SimpleMachines / SMF2.1

	$allday = isset($_REQUEST['allday']) ? 1 : (isset($_REQUEST['start_time']) ? 0 : 1);

	$span = isset($_REQUEST['span']) && filter_var($_REQUEST['span'], FILTER_VALIDATE_INT, array('options' => array('min_range' => 0))) ? $_REQUEST['span'] : 1;

	if (!empty($_REQUEST['tz']) && in_array($_REQUEST['tz'], timezone_identifiers_list(DateTimeZone::ALL_WITH_BC)))

		$tz = $_REQUEST['tz'];

	else

		$tz = getUserTimezone();

	// Was the input given as individual parameters?

	$start_year = isset($_REQUEST['year']) ? $_REQUEST['year'] : $today['year'];

	// Define the timezone for this event, falling back to the default if not provided

	if (!empty($eventOptions['tz']) && in_array($eventOptions['tz'], timezone_identifiers_list(DateTimeZone::ALL_WITH_BC)))

		$tz = $eventOptions['tz'];

	elseif (!empty($_POST['tz']) && in_array($_POST['tz'], timezone_identifiers_list(DateTimeZone::ALL_WITH_BC)))

		$tz = $_POST['tz'];

	else

		$tz = getUserTimezone();

		$smcFunc['db_free_result']($request);

	}

	if (empty($timezone) || !in_array($timezone, timezone_identifiers_list(DateTimeZone::ALL_WITH_BC)))

		$timezone = isset($modSettings['default_timezone']) ? $modSettings['default_timezone'] : date_default_timezone_get();

	return $timezone;

}