CCalendarEvent::CanView

static function CanView($eventId, $userId)
{
	if ((int)$eventId > 0)
	{
		Loader::includeModule("calendar");
		$event = self::GetList(
			array(
				'arFilter' => array(
					"ID" => $eventId,
				),
				'parseRecursion' => false,
				'fetchAttendees' => true,
				'checkPermissions' => true,
				'userId' => $userId,
			)
		);

		if (!$event || !is_array($event[0]))
		{
			$event = self::GetList(
				array(
					'arFilter' => array(
						"PARENT_ID" => $eventId,
						"CREATED_BY" => $userId
					),
					'parseRecursion' => false,
					'fetchAttendees' => true,
					'checkPermissions' => true,
					'userId' => $userId,
				)
			);
		}

		// Event is not partly accessible - so it was not cleaned before by ApplyAccessRestrictions
		if (
			$event
			&& is_array($event[0])
			&& ($event[0]['IS_ACCESSIBLE_TO_USER'] ?? null) !== false
			&& (
				isset($event[0]['DESCRIPTION'])
				|| isset($event[0]['IS_MEETING'])
				|| isset($event[0]['LOCATION'])
			)
		)
		{
			return true;
		}

	}

	return false;
}