fix(caldav): Fix reminder timezone drift for all-day events

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>

3 files changed, 237 insertions, 16 deletions

diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index 8108260797c..709f625afb3 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -675,7 +675,7 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	}
 
 	/**
-	 * @return array{id: int, uri: string, '{http://calendarserver.org/ns/}getctag': string, '{http://sabredav.org/ns}sync-token': int, '{urn:ietf:params:xml:ns:caldav}supported-calendar-component-set': SupportedCalendarComponentSet, '{urn:ietf:params:xml:ns:caldav}schedule-calendar-transp': ScheduleCalendarTransp }|null
+	 * @return array{id: int, uri: string, '{http://calendarserver.org/ns/}getctag': string, '{http://sabredav.org/ns}sync-token': int, '{urn:ietf:params:xml:ns:caldav}supported-calendar-component-set': SupportedCalendarComponentSet, '{urn:ietf:params:xml:ns:caldav}schedule-calendar-transp': ScheduleCalendarTransp, '{urn:ietf:params:xml:ns:caldav}calendar-timezone': ?string }|null
 	 */
 	public function getCalendarById(int $calendarId): ?array {
 		$fields = array_column($this->propertyMap, 0);
diff --git a/apps/dav/lib/CalDAV/Reminder/ReminderService.php b/apps/dav/lib/CalDAV/Reminder/ReminderService.php
index 1da471a51f5..a2daa3cc98e 100644
--- a/apps/dav/lib/CalDAV/Reminder/ReminderService.php
+++ b/apps/dav/lib/CalDAV/Reminder/ReminderService.php
@@ -32,6 +32,7 @@ declare(strict_types=1);
 namespace OCA\DAV\CalDAV\Reminder;
 
 use DateTimeImmutable;
+use DateTimeZone;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\Connector\Sabre\Principal;
 use OCP\AppFramework\Utility\ITimeFactory;
@@ -221,6 +222,7 @@ class ReminderService {
 		if (!$vcalendar) {
 			return;
 		}
+		$calendarTimeZone = $this->getCalendarTimeZone((int) $objectData['calendarid']);
 
 		$vevents = $this->getAllVEventsFromVCalendar($vcalendar);
 		if (count($vevents) === 0) {
@@ -249,7 +251,7 @@ class ReminderService {
 					continue;
 				}
 
-				$alarms = $this->getRemindersForVAlarm($valarm, $objectData,
+				$alarms = $this->getRemindersForVAlarm($valarm, $objectData, $calendarTimeZone,
 					$eventHash, $alarmHash, true, true);
 				$this->writeRemindersToDatabase($alarms);
 			}
@@ -306,6 +308,16 @@ class ReminderService {
 
 					try {
 						$triggerTime = $valarm->getEffectiveTriggerTime();
+						/**
+						 * @psalm-suppress DocblockTypeContradiction
+						 *   https://github.com/vimeo/psalm/issues/9244
+						 */
+						if ($triggerTime->getTimezone() === false || $triggerTime->getTimezone()->getName() === 'UTC') {
+							$triggerTime = new DateTimeImmutable(
+								$triggerTime->format('Y-m-d H:i:s'),
+								$calendarTimeZone
+							);
+						}
 					} catch (InvalidDataException $e) {
 						continue;
 					}
@@ -324,7 +336,7 @@ class ReminderService {
 						continue;
 					}
 
-					$alarms = $this->getRemindersForVAlarm($valarm, $objectData, $masterHash, $alarmHash, $isRecurring, false);
+					$alarms = $this->getRemindersForVAlarm($valarm, $objectData, $calendarTimeZone, $masterHash, $alarmHash, $isRecurring, false);
 					$this->writeRemindersToDatabase($alarms);
 					$processedAlarms[] = $alarmHash;
 				}
@@ -363,6 +375,7 @@ class ReminderService {
 	/**
 	 * @param VAlarm $valarm
 	 * @param array $objectData
+	 * @param DateTimeZone $calendarTimeZone
 	 * @param string|null $eventHash
 	 * @param string|null $alarmHash
 	 * @param bool $isRecurring
@@ -371,6 +384,7 @@ class ReminderService {
 	 */
 	private function getRemindersForVAlarm(VAlarm $valarm,
 										   array $objectData,
+										   DateTimeZone $calendarTimeZone,
 										   string $eventHash = null,
 										   string $alarmHash = null,
 										   bool $isRecurring = false,
@@ -386,6 +400,16 @@ class ReminderService {
 		$isRelative = $this->isAlarmRelative($valarm);
 		/** @var DateTimeImmutable $notificationDate */
 		$notificationDate = $valarm->getEffectiveTriggerTime();
+		/**
+		 * @psalm-suppress DocblockTypeContradiction
+		 *   https://github.com/vimeo/psalm/issues/9244
+		 */
+		if ($notificationDate->getTimezone() === false || $notificationDate->getTimezone()->getName() === 'UTC') {
+			$notificationDate = new DateTimeImmutable(
+				$notificationDate->format('Y-m-d H:i:s'),
+				$calendarTimeZone
+			);
+		}
 		$clonedNotificationDate = new \DateTime('now', $notificationDate->getTimezone());
 		$clonedNotificationDate->setTimestamp($notificationDate->getTimestamp());
 
@@ -471,6 +495,7 @@ class ReminderService {
 		$vevents = $this->getAllVEventsFromVCalendar($vevent->parent);
 		$recurrenceExceptions = $this->getRecurrenceExceptionFromListOfVEvents($vevents);
 		$now = $this->timeFactory->getDateTime();
+		$calendarTimeZone = $this->getCalendarTimeZone((int) $reminder['calendar_id']);
 
 		try {
 			$iterator = new EventIterator($vevents, $reminder['uid']);
@@ -517,7 +542,7 @@ class ReminderService {
 					$alarms = $this->getRemindersForVAlarm($valarm, [
 						'calendarid' => $reminder['calendar_id'],
 						'id' => $reminder['object_id'],
-					], $reminder['event_hash'], $alarmHash, true, false);
+					], $calendarTimeZone, $reminder['event_hash'], $alarmHash, true, false);
 					$this->writeRemindersToDatabase($alarms);
 
 					// Abort generating reminders after creating one successfully
@@ -825,4 +850,26 @@ class ReminderService {
 	private function isRecurring(VEvent $vevent):bool {
 		return isset($vevent->RRULE) || isset($vevent->RDATE);
 	}
+
+	/**
+	 * @param int $calendarid
+	 *
+	 * @return DateTimeZone
+	 */
+	private function getCalendarTimeZone(int $calendarid): DateTimeZone {
+		$calendarInfo = $this->caldavBackend->getCalendarById($calendarid);
+		$tzProp = '{urn:ietf:params:xml:ns:caldav}calendar-timezone';
+		if (!isset($calendarInfo[$tzProp])) {
+			// Defaulting to UTC
+			return new DateTimeZone('UTC');
+		}
+		// This property contains a VCALENDAR with a single VTIMEZONE
+		/** @var string $timezoneProp */
+		$timezoneProp = $calendarInfo[$tzProp];
+		/** @var VObject\Component\VCalendar $vtimezoneObj */
+		$vtimezoneObj = VObject\Reader::read($timezoneProp);
+		/** @var VObject\Component\VTimeZone $vtimezone */
+		$vtimezone = $vtimezoneObj->VTIMEZONE;
+		return $vtimezone->getTimeZone();
+	}
 }
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/ReminderServiceTest.php b/apps/dav/tests/unit/CalDAV/Reminder/ReminderServiceTest.php
index 79d9376650b..fa8dd826e51 100644
--- a/apps/dav/tests/unit/CalDAV/Reminder/ReminderServiceTest.php
+++ b/apps/dav/tests/unit/CalDAV/Reminder/ReminderServiceTest.php
@@ -29,6 +29,8 @@ declare(strict_types=1);
  */
 namespace OCA\DAV\Tests\unit\CalDAV\Reminder;
 
+use DateTime;
+use DateTimeZone;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\CalDAV\Reminder\Backend;
 use OCA\DAV\CalDAV\Reminder\INotificationProvider;
@@ -193,6 +195,87 @@ END:VEVENT
 END:VCALENDAR
 EOD;
 
+	private const CALENDAR_DATA_ONE_TIME = <<<EOD
+BEGIN:VCALENDAR
+PRODID:-//IDN nextcloud.com//Calendar app 4.3.0-alpha.0//EN
+CALSCALE:GREGORIAN
+VERSION:2.0
+BEGIN:VEVENT
+CREATED:20230203T154600Z
+DTSTAMP:20230203T154602Z
+LAST-MODIFIED:20230203T154602Z
+SEQUENCE:2
+UID:f6a565b6-f9a8-4d1e-9d01-c8dcbe716b7e
+DTSTART;TZID=Europe/Vienna:20230204T090000
+DTEND;TZID=Europe/Vienna:20230204T120000
+STATUS:CONFIRMED
+SUMMARY:TEST
+BEGIN:VALARM
+ACTION:DISPLAY
+TRIGGER;RELATED=START:-PT1H
+END:VALARM
+END:VEVENT
+BEGIN:VTIMEZONE
+TZID:Europe/Vienna
+BEGIN:DAYLIGHT
+TZOFFSETFROM:+0100
+TZOFFSETTO:+0200
+TZNAME:CEST
+DTSTART:19700329T020000
+RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
+END:DAYLIGHT
+BEGIN:STANDARD
+TZOFFSETFROM:+0200
+TZOFFSETTO:+0100
+TZNAME:CET
+DTSTART:19701025T030000
+RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
+END:STANDARD
+END:VTIMEZONE
+END:VCALENDAR
+EOD;
+
+	private const CALENDAR_DATA_ALL_DAY = <<<EOD
+BEGIN:VCALENDAR
+PRODID:-//IDN nextcloud.com//Calendar app 4.3.0-alpha.0//EN
+CALSCALE:GREGORIAN
+VERSION:2.0
+BEGIN:VEVENT
+CREATED:20230203T113430Z
+DTSTAMP:20230203T113432Z
+LAST-MODIFIED:20230203T113432Z
+SEQUENCE:2
+UID:a163a056-ba26-44a2-8080-955f19611a8f
+DTSTART;VALUE=DATE:20230204
+DTEND;VALUE=DATE:20230205
+STATUS:CONFIRMED
+SUMMARY:TEST
+BEGIN:VALARM
+ACTION:EMAIL
+TRIGGER;RELATED=START:-PT1H
+END:VALARM
+END:VEVENT
+END:VCALENDAR
+EOD;
+
+	private const PAGO_PAGO_VTIMEZONE_ICS = <<<ICS
+BEGIN:VCALENDAR
+BEGIN:VTIMEZONE
+TZID:Pacific/Pago_Pago
+BEGIN:STANDARD
+TZOFFSETFROM:-1100
+TZOFFSETTO:-1100
+TZNAME:SST
+DTSTART:19700101T000000
+END:STANDARD
+END:VTIMEZONE
+END:VCALENDAR
+ICS;
+
+
+	/** @var null|string */
+	private $oldTimezone;
+
 	protected function setUp(): void {
 		parent::setUp();
 
@@ -253,7 +336,7 @@ EOD;
 		$this->timeFactory->expects($this->once())
 			->method('getDateTime')
 			->with()
-			->willReturn(\DateTime::createFromFormat(\DateTime::ATOM, '2016-06-08T00:00:00+00:00'));
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2016-06-08T00:00:00+00:00'));
 
 		$this->reminderService->onCalendarObjectCreate($objectData);
 	}
@@ -280,7 +363,7 @@ EOD;
 		$this->timeFactory->expects($this->once())
 			->method('getDateTime')
 			->with()
-			->willReturn(\DateTime::createFromFormat(\DateTime::ATOM, '2016-06-08T00:00:00+00:00'));
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2016-06-08T00:00:00+00:00'));
 
 		$this->reminderService->onCalendarObjectCreate($objectData);
 	}
@@ -303,8 +386,7 @@ EOD;
 
 		$this->timeFactory->expects($this->once())
 			->method('getDateTime')
-			->with()
-			->willReturn(\DateTime::createFromFormat(\DateTime::ATOM, '2016-06-29T00:00:00+00:00'));
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2016-06-29T00:00:00+00:00'));
 
 		$this->reminderService->onCalendarObjectCreate($objectData);
 	}
@@ -323,6 +405,60 @@ EOD;
 		$this->reminderService->onCalendarObjectCreate($objectData);
 	}
 
+	public function testOnCalendarObjectCreateAllDayWithoutTimezone(): void {
+		$objectData = [
+			'calendardata' => self::CALENDAR_DATA_ALL_DAY,
+			'id' => '42',
+			'calendarid' => '1337',
+			'component' => 'vevent',
+		];
+		$this->timeFactory->expects($this->once())
+			->method('getDateTime')
+			->with()
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2023-02-03T13:28:00+00:00'));
+		$this->caldavBackend->expects(self::once())
+			->method('getCalendarById')
+			->with(1337)
+			->willReturn([
+				'{urn:ietf:params:xml:ns:caldav}calendar-timezone' => null,
+			]);
+
+		// One hour before midnight relative to the server's time
+		$expectedReminderTimstamp = (new DateTime('2023-02-03T23:00:00'))->getTimestamp();
+		$this->backend->expects(self::once())
+			->method('insertReminder')
+			->with(1337, 42, self::anything(), false, 1675468800, false, self::anything(), self::anything(), 'EMAIL', true, $expectedReminderTimstamp, false);
+
+		$this->reminderService->onCalendarObjectCreate($objectData);
+	}
+
+	public function testOnCalendarObjectCreateAllDayWithTimezone(): void {
+		$objectData = [
+			'calendardata' => self::CALENDAR_DATA_ALL_DAY,
+			'id' => '42',
+			'calendarid' => '1337',
+			'component' => 'vevent',
+		];
+		$this->timeFactory->expects($this->once())
+			->method('getDateTime')
+			->with()
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2023-02-03T13:28:00+00:00'));
+		$this->caldavBackend->expects(self::once())
+			->method('getCalendarById')
+			->with(1337)
+			->willReturn([
+				'{urn:ietf:params:xml:ns:caldav}calendar-timezone' => self::PAGO_PAGO_VTIMEZONE_ICS,
+			]);
+
+		// One hour before midnight relative to the timezone
+		$expectedReminderTimstamp = (new DateTime('2023-02-03T23:00:00', new DateTimeZone('Pacific/Pago_Pago')))->getTimestamp();
+		$this->backend->expects(self::once())
+			->method('insertReminder')
+			->with(1337, 42, 'a163a056-ba26-44a2-8080-955f19611a8f', false, self::anything(), false, self::anything(), self::anything(), 'EMAIL', true, $expectedReminderTimstamp, false);
+
+		$this->reminderService->onCalendarObjectCreate($objectData);
+	}
+
 	public function testOnCalendarObjectCreateRecurringEntryWithRepeat():void {
 		$objectData = [
 			'calendardata' => self::CALENDAR_DATA_RECURRING_REPEAT,
@@ -330,7 +466,12 @@ EOD;
 			'calendarid' => '1337',
 			'component' => 'vevent',
 		];
-
+		$this->caldavBackend->expects(self::once())
+			->method('getCalendarById')
+			->with(1337)
+			->willReturn([
+				'{urn:ietf:params:xml:ns:caldav}calendar-timezone' => null,
+			]);
 		$this->backend->expects($this->exactly(6))
 			->method('insertReminder')
 			->withConsecutive(
@@ -342,11 +483,44 @@ EOD;
 				[1337, 42, 'wej2z68l9h', true, 1467849600, false, 'fbdb2726bc0f7dfacac1d881c1453e20', '8996992118817f9f311ac5cc56d1cc97', 'EMAIL', true, 1467158400, false]
 			)
 			->willReturn(1);
+		$this->timeFactory->expects($this->once())
+			->method('getDateTime')
+			->with()
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2016-06-29T00:00:00+00:00'));
+
+		$this->reminderService->onCalendarObjectCreate($objectData);
+	}
 
+	public function testOnCalendarObjectCreateWithEventTimezoneAndCalendarTimezone():void {
+		$objectData = [
+			'calendardata' => self::CALENDAR_DATA_ONE_TIME,
+			'id' => '42',
+			'calendarid' => '1337',
+			'component' => 'vevent',
+		];
+		$this->caldavBackend->expects(self::once())
+			->method('getCalendarById')
+			->with(1337)
+			->willReturn([
+				'{urn:ietf:params:xml:ns:caldav}calendar-timezone' => self::PAGO_PAGO_VTIMEZONE_ICS,
+			]);
+		$expectedReminderTimstamp = (new DateTime('2023-02-04T08:00:00', new DateTimeZone('Europe/Vienna')))->getTimestamp();
+		$this->backend->expects(self::once())
+			->method('insertReminder')
+			->withConsecutive(
+				[1337, 42, self::anything(), false, self::anything(), false, self::anything(), self::anything(), self::anything(), true, $expectedReminderTimstamp, false],
+			)
+			->willReturn(1);
+		$this->caldavBackend->expects(self::once())
+			->method('getCalendarById')
+			->with(1337)
+			->willReturn([
+				'{urn:ietf:params:xml:ns:caldav}calendar-timezone' => null,
+			]);
 		$this->timeFactory->expects($this->once())
 			->method('getDateTime')
 			->with()
-			->willReturn(\DateTime::createFromFormat(\DateTime::ATOM, '2016-06-29T00:00:00+00:00'));
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2023-02-03T13:28:00+00:00'));;
 
 		$this->reminderService->onCalendarObjectCreate($objectData);
 	}
@@ -512,7 +686,7 @@ EOD;
 		$provider1->expects($this->once())
 			->method('send')
 			->with($this->callback(function ($vevent) {
-				if ($vevent->DTSTART->getDateTime()->format(\DateTime::ATOM) !== '2016-06-09T00:00:00+00:00') {
+				if ($vevent->DTSTART->getDateTime()->format(DateTime::ATOM) !== '2016-06-09T00:00:00+00:00') {
 					return false;
 				}
 				return true;
@@ -520,7 +694,7 @@ EOD;
 		$provider2->expects($this->once())
 			->method('send')
 			->with($this->callback(function ($vevent) {
-				if ($vevent->DTSTART->getDateTime()->format(\DateTime::ATOM) !== '2016-06-09T00:00:00+00:00') {
+				if ($vevent->DTSTART->getDateTime()->format(DateTime::ATOM) !== '2016-06-09T00:00:00+00:00') {
 					return false;
 				}
 				return true;
@@ -528,7 +702,7 @@ EOD;
 		$provider3->expects($this->once())
 			->method('send')
 			->with($this->callback(function ($vevent) {
-				if ($vevent->DTSTART->getDateTime()->format(\DateTime::ATOM) !== '2016-06-09T00:00:00+00:00') {
+				if ($vevent->DTSTART->getDateTime()->format(DateTime::ATOM) !== '2016-06-09T00:00:00+00:00') {
 					return false;
 				}
 				return true;
@@ -536,7 +710,7 @@ EOD;
 		$provider4->expects($this->once())
 			->method('send')
 			->with($this->callback(function ($vevent) {
-				if ($vevent->DTSTART->getDateTime()->format(\DateTime::ATOM) !== '2016-06-30T00:00:00+00:00') {
+				if ($vevent->DTSTART->getDateTime()->format(DateTime::ATOM) !== '2016-06-30T00:00:00+00:00') {
 					return false;
 				}
 				return true;
@@ -544,7 +718,7 @@ EOD;
 		$provider5->expects($this->once())
 			->method('send')
 			->with($this->callback(function ($vevent) {
-				if ($vevent->DTSTART->getDateTime()->format(\DateTime::ATOM) !== '2016-07-07T00:00:00+00:00') {
+				if ($vevent->DTSTART->getDateTime()->format(DateTime::ATOM) !== '2016-07-07T00:00:00+00:00') {
 					return false;
 				}
 				return true;
@@ -592,7 +766,7 @@ EOD;
 			->willReturn(99);
 
 		$this->timeFactory->method('getDateTime')
-			->willReturn(\DateTime::createFromFormat(\DateTime::ATOM, '2016-06-08T00:00:00+00:00'));
+			->willReturn(DateTime::createFromFormat(DateTime::ATOM, '2016-06-08T00:00:00+00:00'));
 
 		$this->reminderService->processReminders();
 	}