Support event reminders (email and notifications)

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

28 files changed, 2711 insertions, 6 deletions

diff --git a/apps/dav/appinfo/app.php b/apps/dav/appinfo/app.php
index 70d01088be2..dd9e0e9c096 100644
--- a/apps/dav/appinfo/app.php
+++ b/apps/dav/appinfo/app.php
@@ -108,3 +108,6 @@ $calendarManager->register(function() use ($calendarManager, $app) {
 		$app->setupCalendarProvider($calendarManager, $user->getUID());
 	}
 });
+
+$app->registerNotifier();
+$app->registerCalendarReminders();
diff --git a/apps/dav/appinfo/info.xml b/apps/dav/appinfo/info.xml
index dc90ac58188..91617e90024 100644
--- a/apps/dav/appinfo/info.xml
+++ b/apps/dav/appinfo/info.xml
@@ -23,6 +23,7 @@
 		<job>OCA\DAV\BackgroundJob\CleanupDirectLinksJob</job>
 		<job>OCA\DAV\BackgroundJob\UpdateCalendarResourcesRoomsBackgroundJob</job>
 		<job>OCA\DAV\BackgroundJob\CleanupInvitationTokenJob</job>
+		<job>OCA\DAV\BackgroundJob\EventReminderJob</job>
 	</background-jobs>
 
 	<repair-steps>
diff --git a/apps/dav/composer/composer/autoload_classmap.php b/apps/dav/composer/composer/autoload_classmap.php
index 694231eebda..33977f31668 100644
--- a/apps/dav/composer/composer/autoload_classmap.php
+++ b/apps/dav/composer/composer/autoload_classmap.php
@@ -13,6 +13,7 @@ return array(
     'OCA\\DAV\\Avatars\\RootCollection' => $baseDir . '/../lib/Avatars/RootCollection.php',
     'OCA\\DAV\\BackgroundJob\\CleanupDirectLinksJob' => $baseDir . '/../lib/BackgroundJob/CleanupDirectLinksJob.php',
     'OCA\\DAV\\BackgroundJob\\CleanupInvitationTokenJob' => $baseDir . '/../lib/BackgroundJob/CleanupInvitationTokenJob.php',
+    'OCA\\DAV\\BackgroundJob\\EventReminderJob' => $baseDir . '/../lib/BackgroundJob/EventReminderJob.php',
     'OCA\\DAV\\BackgroundJob\\GenerateBirthdayCalendarBackgroundJob' => $baseDir . '/../lib/BackgroundJob/GenerateBirthdayCalendarBackgroundJob.php',
     'OCA\\DAV\\BackgroundJob\\RefreshWebcalJob' => $baseDir . '/../lib/BackgroundJob/RefreshWebcalJob.php',
     'OCA\\DAV\\BackgroundJob\\RegisterRegenerateBirthdayCalendars' => $baseDir . '/../lib/BackgroundJob/RegisterRegenerateBirthdayCalendars.php',
@@ -51,6 +52,15 @@ return array(
     'OCA\\DAV\\CalDAV\\PublicCalendarRoot' => $baseDir . '/../lib/CalDAV/PublicCalendarRoot.php',
     'OCA\\DAV\\CalDAV\\Publishing\\PublishPlugin' => $baseDir . '/../lib/CalDAV/Publishing/PublishPlugin.php',
     'OCA\\DAV\\CalDAV\\Publishing\\Xml\\Publisher' => $baseDir . '/../lib/CalDAV/Publishing/Xml/Publisher.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\AbstractNotificationProvider' => $baseDir . '/../lib/CalDAV/Reminder/AbstractNotificationProvider.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\Backend' => $baseDir . '/../lib/CalDAV/Reminder/Backend.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\NotificationProviderManager' => $baseDir . '/../lib/CalDAV/Reminder/NotificationProviderManager.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\NotificationProvider\\EmailProvider' => $baseDir . '/../lib/CalDAV/Reminder/NotificationProvider/EmailProvider.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\NotificationProvider\\ProviderNotAvailableException' => $baseDir . '/../lib/CalDAV/Reminder/NotificationProvider/ProviderNotAvailableException.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\NotificationProvider\\PushProvider' => $baseDir . '/../lib/CalDAV/Reminder/NotificationProvider/PushProvider.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\NotificationTypeDoesNotExistException' => $baseDir . '/../lib/CalDAV/Reminder/NotificationTypeDoesNotExistException.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\Notifier' => $baseDir . '/../lib/CalDAV/Reminder/Notifier.php',
+    'OCA\\DAV\\CalDAV\\Reminder\\ReminderService' => $baseDir . '/../lib/CalDAV/Reminder/ReminderService.php',
     'OCA\\DAV\\CalDAV\\ResourceBooking\\AbstractPrincipalBackend' => $baseDir . '/../lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php',
     'OCA\\DAV\\CalDAV\\ResourceBooking\\ResourcePrincipalBackend' => $baseDir . '/../lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php',
     'OCA\\DAV\\CalDAV\\ResourceBooking\\RoomPrincipalBackend' => $baseDir . '/../lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php',
@@ -176,6 +186,7 @@ return array(
     'OCA\\DAV\\Migration\\Version1005Date20180530124431' => $baseDir . '/../lib/Migration/Version1005Date20180530124431.php',
     'OCA\\DAV\\Migration\\Version1006Date20180619154313' => $baseDir . '/../lib/Migration/Version1006Date20180619154313.php',
     'OCA\\DAV\\Migration\\Version1006Date20180628111625' => $baseDir . '/../lib/Migration/Version1006Date20180628111625.php',
+    'OCA\\DAV\\Migration\\Version1007Date20181005133326' => $baseDir . '/../lib/Migration/Version1007Date20181005133326.php',
     'OCA\\DAV\\Migration\\Version1008Date20181030113700' => $baseDir . '/../lib/Migration/Version1008Date20181030113700.php',
     'OCA\\DAV\\Migration\\Version1008Date20181105104826' => $baseDir . '/../lib/Migration/Version1008Date20181105104826.php',
     'OCA\\DAV\\Migration\\Version1008Date20181105104833' => $baseDir . '/../lib/Migration/Version1008Date20181105104833.php',
diff --git a/apps/dav/composer/composer/autoload_static.php b/apps/dav/composer/composer/autoload_static.php
index 6f104916077..8ca83bb8b75 100644
--- a/apps/dav/composer/composer/autoload_static.php
+++ b/apps/dav/composer/composer/autoload_static.php
@@ -28,6 +28,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\Avatars\\RootCollection' => __DIR__ . '/..' . '/../lib/Avatars/RootCollection.php',
         'OCA\\DAV\\BackgroundJob\\CleanupDirectLinksJob' => __DIR__ . '/..' . '/../lib/BackgroundJob/CleanupDirectLinksJob.php',
         'OCA\\DAV\\BackgroundJob\\CleanupInvitationTokenJob' => __DIR__ . '/..' . '/../lib/BackgroundJob/CleanupInvitationTokenJob.php',
+        'OCA\\DAV\\BackgroundJob\\EventReminderJob' => __DIR__ . '/..' . '/../lib/BackgroundJob/EventReminderJob.php',
         'OCA\\DAV\\BackgroundJob\\GenerateBirthdayCalendarBackgroundJob' => __DIR__ . '/..' . '/../lib/BackgroundJob/GenerateBirthdayCalendarBackgroundJob.php',
         'OCA\\DAV\\BackgroundJob\\RefreshWebcalJob' => __DIR__ . '/..' . '/../lib/BackgroundJob/RefreshWebcalJob.php',
         'OCA\\DAV\\BackgroundJob\\RegisterRegenerateBirthdayCalendars' => __DIR__ . '/..' . '/../lib/BackgroundJob/RegisterRegenerateBirthdayCalendars.php',
@@ -66,6 +67,15 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\CalDAV\\PublicCalendarRoot' => __DIR__ . '/..' . '/../lib/CalDAV/PublicCalendarRoot.php',
         'OCA\\DAV\\CalDAV\\Publishing\\PublishPlugin' => __DIR__ . '/..' . '/../lib/CalDAV/Publishing/PublishPlugin.php',
         'OCA\\DAV\\CalDAV\\Publishing\\Xml\\Publisher' => __DIR__ . '/..' . '/../lib/CalDAV/Publishing/Xml/Publisher.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\AbstractNotificationProvider' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/AbstractNotificationProvider.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\Backend' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/Backend.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\NotificationProviderManager' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/NotificationProviderManager.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\NotificationProvider\\EmailProvider' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/NotificationProvider/EmailProvider.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\NotificationProvider\\ProviderNotAvailableException' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/NotificationProvider/ProviderNotAvailableException.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\NotificationProvider\\PushProvider' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/NotificationProvider/PushProvider.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\NotificationTypeDoesNotExistException' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/NotificationTypeDoesNotExistException.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\Notifier' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/Notifier.php',
+        'OCA\\DAV\\CalDAV\\Reminder\\ReminderService' => __DIR__ . '/..' . '/../lib/CalDAV/Reminder/ReminderService.php',
         'OCA\\DAV\\CalDAV\\ResourceBooking\\AbstractPrincipalBackend' => __DIR__ . '/..' . '/../lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php',
         'OCA\\DAV\\CalDAV\\ResourceBooking\\ResourcePrincipalBackend' => __DIR__ . '/..' . '/../lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php',
         'OCA\\DAV\\CalDAV\\ResourceBooking\\RoomPrincipalBackend' => __DIR__ . '/..' . '/../lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php',
@@ -191,6 +201,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\Migration\\Version1005Date20180530124431' => __DIR__ . '/..' . '/../lib/Migration/Version1005Date20180530124431.php',
         'OCA\\DAV\\Migration\\Version1006Date20180619154313' => __DIR__ . '/..' . '/../lib/Migration/Version1006Date20180619154313.php',
         'OCA\\DAV\\Migration\\Version1006Date20180628111625' => __DIR__ . '/..' . '/../lib/Migration/Version1006Date20180628111625.php',
+        'OCA\\DAV\\Migration\\Version1007Date20181005133326' => __DIR__ . '/..' . '/../lib/Migration/Version1007Date20181005133326.php',
         'OCA\\DAV\\Migration\\Version1008Date20181030113700' => __DIR__ . '/..' . '/../lib/Migration/Version1008Date20181030113700.php',
         'OCA\\DAV\\Migration\\Version1008Date20181105104826' => __DIR__ . '/..' . '/../lib/Migration/Version1008Date20181105104826.php',
         'OCA\\DAV\\Migration\\Version1008Date20181105104833' => __DIR__ . '/..' . '/../lib/Migration/Version1008Date20181105104833.php',
diff --git a/apps/dav/js/settings-admin-caldav.js b/apps/dav/js/settings-admin-caldav.js
index 1a40c208dfe..ad30ba6ad37 100644
--- a/apps/dav/js/settings-admin-caldav.js
+++ b/apps/dav/js/settings-admin-caldav.js
@@ -36,3 +36,9 @@ $('#caldavGenerateBirthdayCalendar').change(function() {
 		$.post(OC.generateUrl('/apps/dav/disableBirthdayCalendar'));
 	}
 });
+
+$('#caldavSendRemindersNotifications').change(function() {
+	var val = $(this)[0].checked;
+
+	OCP.AppConfig.setValue('dav', 'sendEventReminders', val ? 'yes' : 'no');
+});
diff --git a/apps/dav/lib/AppInfo/Application.php b/apps/dav/lib/AppInfo/Application.php
index 41570ee7442..2e3b95d8bfa 100644
--- a/apps/dav/lib/AppInfo/Application.php
+++ b/apps/dav/lib/AppInfo/Application.php
@@ -30,6 +30,12 @@ use OCA\DAV\CalDAV\Activity\Backend;
 use OCA\DAV\CalDAV\Activity\Provider\Event;
 use OCA\DAV\CalDAV\BirthdayService;
 use OCA\DAV\CalDAV\CalendarManager;
+use OCA\DAV\CalDAV\Reminder\Backend as ReminderBackend;
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\EmailProvider;
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\PushProvider;
+use OCA\DAV\CalDAV\Reminder\NotificationProviderManager;
+use OCA\DAV\CalDAV\Reminder\Notifier;
+use OCA\DAV\CalDAV\Reminder\ReminderService;
 use OCA\DAV\Capabilities;
 use OCA\DAV\CardDAV\ContactsManager;
 use OCA\DAV\CardDAV\PhotoCache;
@@ -43,6 +49,8 @@ use Symfony\Component\EventDispatcher\GenericEvent;
 
 class Application extends App {
 
+	const APP_ID = 'dav';
+
 	/**
 	 * Application constructor.
 	 */
@@ -109,8 +117,7 @@ class Application extends App {
 			}
 		});
 
-		// carddav/caldav sync event setup
-		$listener = function($event) {
+		$birthdayListener = function ($event) {
 			if ($event instanceof GenericEvent) {
 				/** @var BirthdayService $b */
 				$b = $this->getContainer()->query(BirthdayService::class);
@@ -122,9 +129,9 @@ class Application extends App {
 			}
 		};
 
-		$dispatcher->addListener('\OCA\DAV\CardDAV\CardDavBackend::createCard', $listener);
-		$dispatcher->addListener('\OCA\DAV\CardDAV\CardDavBackend::updateCard', $listener);
-		$dispatcher->addListener('\OCA\DAV\CardDAV\CardDavBackend::deleteCard', function($event) {
+		$dispatcher->addListener('\OCA\DAV\CardDAV\CardDavBackend::createCard', $birthdayListener);
+		$dispatcher->addListener('\OCA\DAV\CardDAV\CardDavBackend::updateCard', $birthdayListener);
+		$dispatcher->addListener('\OCA\DAV\CardDAV\CardDavBackend::deleteCard', function ($event) {
 			if ($event instanceof GenericEvent) {
 				/** @var BirthdayService $b */
 				$b = $this->getContainer()->query(BirthdayService::class);
@@ -177,6 +184,11 @@ class Application extends App {
 				$event->getArgument('calendarData'),
 				$event->getArgument('shares')
 			);
+
+			$reminderBackend = $this->getContainer()->query(ReminderBackend::class);
+			$reminderBackend->cleanRemindersForCalendar(
+				$event->getArgument('calendarId')
+			);
 		});
 		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::updateShares', function(GenericEvent $event) {
 			/** @var Backend $backend */
@@ -187,6 +199,8 @@ class Application extends App {
 				$event->getArgument('add'),
 				$event->getArgument('remove')
 			);
+
+			// Here we should recalculate if reminders should be sent to new or old sharees
 		});
 
 		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::publishCalendar', function(GenericEvent $event) {
@@ -214,6 +228,16 @@ class Application extends App {
 				$event->getArgument('shares'),
 				$event->getArgument('objectData')
 			);
+
+			/** @var ReminderService $reminderBackend */
+			$reminderService= $this->getContainer()->query(ReminderService::class);
+
+			$reminderService->onTouchCalendarObject(
+				$eventName,
+				$event->getArgument('calendarData'),
+				$event->getArgument('shares'),
+				$event->getArgument('objectData')
+			);
 		};
 		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject', $listener);
 		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject', $listener);
@@ -224,4 +248,28 @@ class Application extends App {
 		return $this->getContainer()->query(SyncService::class);
 	}
 
+	public function registerNotifier() {
+		$this->getContainer()->getServer()->getNotificationManager()->registerNotifier(function() {
+			return $this->getContainer()->query(Notifier::class);
+		}, function() {
+			$l = $this->getContainer()->getServer()->getL10NFactory()->get(self::APP_ID);
+			return [
+				'id' => self::APP_ID,
+				'name' => $l->t('Calendars and Contacts'),
+			];
+		});
+	}
+
+	public function registerCalendarReminders(): void
+	{
+		try {
+			/** @var NotificationProviderManager $notificationProviderManager */
+			$notificationProviderManager = $this->getContainer()->query(NotificationProviderManager::class);
+			$notificationProviderManager->registerProvider(EmailProvider::class);
+			$notificationProviderManager->registerProvider(PushProvider::class);
+		} catch(\Exception $ex) {
+			$this->getContainer()->getServer()->getLogger()->logException($ex);
+		}
+	}
+
 }
diff --git a/apps/dav/lib/BackgroundJob/EventReminderJob.php b/apps/dav/lib/BackgroundJob/EventReminderJob.php
new file mode 100644
index 00000000000..e0a147e4203
--- /dev/null
+++ b/apps/dav/lib/BackgroundJob/EventReminderJob.php
@@ -0,0 +1,59 @@
+<?php
+/**
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\BackgroundJob;
+
+use OC\BackgroundJob\TimedJob;
+use OCA\DAV\CalDAV\Reminder\ReminderService;
+use OCP\IConfig;
+
+class EventReminderJob extends TimedJob {
+
+	/** @var ReminderService */
+	private $reminderService;
+
+	/** @var IConfig */
+	private $config;
+
+	/**
+	 * EventReminderJob constructor.
+	 *
+	 * @param ReminderService $reminderService
+	 * @param IConfig $config
+	 */
+	public function __construct(ReminderService $reminderService, IConfig $config) {
+		$this->reminderService = $reminderService;
+		$this->config = $config;
+		/** Run every 5 minutes */
+		$this->setInterval(5);
+	}
+
+	/**
+	 * @param $arg
+	 * @throws \OCA\DAV\CalDAV\Reminder\NotificationProvider\ProviderNotAvailableException
+	 * @throws \OCA\DAV\CalDAV\Reminder\NotificationTypeDoesNotExistException
+	 * @throws \OC\User\NoUserException
+	 */
+	public function run($arg): void
+	{
+		if ($this->config->getAppValue('dav', 'sendEventReminders', 'yes') === 'yes') {
+			$this->reminderService->processReminders();
+		}
+	}
+}
diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index 91281dc0cb3..62d3909ce39 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -1135,7 +1135,6 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 */
 	function updateCalendarObject($calendarId, $objectUri, $calendarData, $calendarType=self::CALENDAR_TYPE_CALENDAR) {
 		$extraData = $this->getDenormalizedData($calendarData);
-
 		$query = $this->db->getQueryBuilder();
 		$query->update('calendarobjects')
 				->set('calendardata', $query->createNamedParameter($calendarData, IQueryBuilder::PARAM_LOB))
diff --git a/apps/dav/lib/CalDAV/Reminder/AbstractNotificationProvider.php b/apps/dav/lib/CalDAV/Reminder/AbstractNotificationProvider.php
new file mode 100644
index 00000000000..ba928fac80f
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/AbstractNotificationProvider.php
@@ -0,0 +1,208 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Reminder;
+
+use \DateTime;
+use \DateTimeImmutable;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\ILogger;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory as L10NFactory;
+use OCP\IUser;
+use Sabre\VObject\Component\VCalendar;
+use Sabre\VObject\Component\VEvent;
+use Sabre\VObject\DateTimeParser;
+use Sabre\VObject\Parameter;
+use Sabre\VObject\Property;
+
+abstract class AbstractNotificationProvider
+{
+
+	public const NOTIFICATION_TYPE = '';
+
+    /** @var ILogger */
+    protected $logger;
+
+    /** @var L10NFactory */
+    protected $l10nFactory;
+
+    /** @var IL10N */
+    protected $l10n;
+
+    /** @var IURLGenerator */
+    protected $urlGenerator;
+
+    /** @var IConfig */
+	protected $config;
+
+	/**
+	 * @param ILogger $logger
+	 * @param L10NFactory $l10nFactory
+	 * @param IConfig $config
+	 * @param IUrlGenerator $urlGenerator
+	 */
+	public function __construct(ILogger $logger, L10NFactory $l10nFactory, IURLGenerator $urlGenerator, IConfig $config) {
+		$this->logger = $logger;
+		$this->l10nFactory = $l10nFactory;
+        $this->urlGenerator = $urlGenerator;
+		$this->config = $config;
+    }
+
+	/**
+	 * Send notification
+	 *
+	 * @param VCalendar $vcalendar
+	 * @param string $calendarDisplayName
+	 * @param IUser $user
+	 * @return void
+	 */
+    public function send(VCalendar $vcalendar, string $calendarDisplayName, IUser $user): void {}
+
+	/**
+	 * @var VCalendar $vcalendar
+	 * @var string $defaultValue
+	 * @return array
+	 * @throws \Exception
+	 */
+    protected function extractEventDetails(VCalendar $vcalendar, $defaultValue = ''): array
+	{
+		/** @var VEvent $vevent */
+        $vevent = $vcalendar->VEVENT;
+
+        /** @var Property $start */
+		$start = $vevent->DTSTART;
+		if (isset($vevent->DTEND)) {
+			$end = $vevent->DTEND;
+		} elseif (isset($vevent->DURATION)) {
+			$isFloating = $vevent->DTSTART->isFloating();
+			$end = clone $vevent->DTSTART;
+			$endDateTime = $end->getDateTime();
+			$endDateTime = $endDateTime->add(DateTimeParser::parse($vevent->DURATION->getValue()));
+			$end->setDateTime($endDateTime, $isFloating);
+		} elseif (!$vevent->DTSTART->hasTime()) {
+			$isFloating = $vevent->DTSTART->isFloating();
+			$end = clone $vevent->DTSTART;
+			$endDateTime = $end->getDateTime();
+			$endDateTime = $endDateTime->modify('+1 day');
+			$end->setDateTime($endDateTime, $isFloating);
+		} else {
+			$end = clone $vevent->DTSTART;
+		}
+
+        return [
+            'title' => (string) $vevent->SUMMARY ?: $defaultValue,
+            'description' => (string) $vevent->DESCRIPTION ?: $defaultValue,
+            'start'=> $start->getDateTime(),
+            'end' => $end->getDateTime(),
+            'when' => $this->generateWhenString($start, $end),
+            'url' => (string) $vevent->URL ?: $defaultValue,
+            'location' => (string) $vevent->LOCATION ?: $defaultValue,
+            'uid' => (string) $vevent->UID,
+        ];
+    }
+
+	/**
+	 * @param Property $dtstart
+	 * @param Property $dtend
+	 * @return string
+	 * @throws \Exception
+	 */
+	private function generateWhenString(Property $dtstart, Property $dtend): string
+	{
+		$isAllDay = $dtstart instanceof Property\ICalendar\Date;
+
+		/** @var Property\ICalendar\Date | Property\ICalendar\DateTime $dtstart */
+		/** @var Property\ICalendar\Date | Property\ICalendar\DateTime $dtend */
+		/** @var DateTimeImmutable $dtstartDt */
+		$dtstartDt = $dtstart->getDateTime();
+		/** @var DateTimeImmutable $dtendDt */
+		$dtendDt = $dtend->getDateTime();
+
+		$diff = $dtstartDt->diff($dtendDt);
+
+		$dtstartDt = new DateTime($dtstartDt->format(DateTime::ATOM));
+		$dtendDt = new DateTime($dtendDt->format(DateTime::ATOM));
+
+		if ($isAllDay) {
+			// One day event
+			if ($diff->days === 1) {
+				return $this->l10n->l('date', $dtstartDt, ['width' => 'medium']);
+			}
+
+			//event that spans over multiple days
+			$localeStart = $this->l10n->l('date', $dtstartDt, ['width' => 'medium']);
+			$localeEnd = $this->l10n->l('date', $dtendDt, ['width' => 'medium']);
+
+			return $localeStart . ' - ' . $localeEnd;
+		}
+
+		/** @var Property\ICalendar\DateTime $dtstart */
+		/** @var Property\ICalendar\DateTime $dtend */
+		$isFloating = $dtstart->isFloating();
+		$startTimezone = $endTimezone = null;
+		if (!$isFloating) {
+			$prop = $dtstart->offsetGet('TZID');
+			if ($prop instanceof Parameter) {
+				$startTimezone = $prop->getValue();
+			}
+
+			$prop = $dtend->offsetGet('TZID');
+			if ($prop instanceof Parameter) {
+				$endTimezone = $prop->getValue();
+			}
+		}
+
+		$localeStart = $this->l10n->l('weekdayName', $dtstartDt, ['width' => 'abbreviated']) . ', ' .
+			$this->l10n->l('datetime', $dtstartDt, ['width' => 'medium|short']);
+
+		// always show full date with timezone if timezones are different
+		if ($startTimezone !== $endTimezone) {
+			$localeEnd = $this->l10n->l('datetime', $dtendDt, ['width' => 'medium|short']);
+
+			return $localeStart . ' (' . $startTimezone . ') - ' .
+				$localeEnd . ' (' . $endTimezone . ')';
+		}
+
+		// show only end time if date is the same
+		if ($this->isDayEqual($dtstartDt, $dtendDt)) {
+			$localeEnd = $this->l10n->l('time', $dtendDt, ['width' => 'short']);
+		} else {
+			$localeEnd = $this->l10n->l('weekdayName', $dtendDt, ['width' => 'abbreviated']) . ', ' .
+				$this->l10n->l('datetime', $dtendDt, ['width' => 'medium|short']);
+		}
+
+		return  $localeStart . ' - ' . $localeEnd . ' (' . $startTimezone . ')';
+	}
+
+	/**
+	 * @param DateTime $dtStart
+	 * @param DateTime $dtEnd
+	 * @return bool
+	 */
+    private function isDayEqual(DateTime $dtStart, DateTime $dtEnd): bool
+    {
+		return $dtStart->format('Y-m-d') === $dtEnd->format('Y-m-d');
+	}
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/Backend.php b/apps/dav/lib/CalDAV/Reminder/Backend.php
new file mode 100644
index 00000000000..c85e7c365dc
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/Backend.php
@@ -0,0 +1,139 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Reminder;
+
+use OCP\IDBConnection;
+use OCP\AppFramework\Utility\ITimeFactory;
+
+/**
+ * Class Backend
+ *
+ * @package OCA\DAV\CalDAV\Reminder
+ */
+class Backend {
+
+	/** @var IDBConnection */
+	protected $db;
+
+	/** @var ITimeFactory */
+	private $timeFactory;
+
+	/**
+	 * @param IDBConnection $db
+	 * @param ITimeFactory $timeFactory
+	 */
+	public function __construct(IDBConnection $db, ITimeFactory $timeFactory) {
+		$this->db = $db;
+		$this->timeFactory = $timeFactory;
+	}
+
+	/**
+	 * @param string $uid
+	 * @param string $calendarId
+	 * @param string $uri
+	 * @param string $type
+	 * @param int $notificationDate
+	 * @param int $eventStartDate
+	 */
+	public function insertReminder(string $uid, string $calendarId, string $uri, string $type, int $notificationDate, int $eventStartDate): void
+	{
+		$query = $this->db->getQueryBuilder();
+		$query->insert('calendar_reminders')
+			->values([
+				'uid' => $query->createNamedParameter($uid),
+				'calendarid' => $query->createNamedParameter($calendarId),
+				'objecturi' => $query->createNamedParameter($uri),
+				'type' => $query->createNamedParameter($type),
+				'notificationdate' => $query->createNamedParameter($notificationDate),
+				'eventstartdate' => $query->createNamedParameter($eventStartDate),
+			])->execute();
+	}
+
+	/**
+	 * Cleans reminders in database
+	 *
+	 * @param int $calendarId
+	 * @param string $objectUri
+	 */
+	public function cleanRemindersForEvent(int $calendarId, string $objectUri): void
+	{
+		$query = $this->db->getQueryBuilder();
+
+		$query->delete('calendar_reminders')
+			->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
+			->andWhere($query->expr()->eq('objecturi', $query->createNamedParameter($objectUri)))
+			->execute();
+	}
+
+	/**
+	 * Remove all reminders for a calendar
+	 *
+	 * @param integer $calendarId
+	 * @return void
+	 */
+	public function cleanRemindersForCalendar(int $calendarId): void
+	{
+		$query = $this->db->getQueryBuilder();
+
+		$query->delete('calendar_reminders')
+			->where($query->expr()->eq('calendarid', $query->createNamedParameter($calendarId)))
+			->execute();
+	}
+
+	/**
+	 * Remove a reminder by it's id
+	 *
+	 * @param integer $reminderId
+	 * @return void
+	 */
+	public function removeReminder(int $reminderId): void
+	{
+		$query = $this->db->getQueryBuilder();
+
+		$query->delete('calendar_reminders')
+			->where($query->expr()->eq('id', $query->createNamedParameter($reminderId)))
+			->execute();
+	}
+
+	/**
+	 * Get all reminders with a notification date before now
+	 *
+	 * @return array
+	 * @throws \Exception
+	 */
+	public function getRemindersToProcess(): array
+	{
+		$query = $this->db->getQueryBuilder();
+		$fields = ['cr.id', 'cr.calendarid', 'cr.objecturi', 'cr.type', 'cr.notificationdate', 'cr.uid', 'co.calendardata', 'c.displayname'];
+		$stmt = $query->select($fields)
+			->from('calendar_reminders', 'cr')
+			->where($query->expr()->lte('cr.notificationdate', $query->createNamedParameter($this->timeFactory->getTime())))
+			->andWhere($query->expr()->gte('cr.eventstartdate', $query->createNamedParameter($this->timeFactory->getTime()))) # We check that DTSTART isn't before
+			->leftJoin('cr', 'calendars', 'c', $query->expr()->eq('cr.calendarid', 'c.id'))
+			->leftJoin('cr', 'calendarobjects', 'co', $query->expr()->andX($query->expr()->eq('cr.calendarid', 'c.id'), $query->expr()->eq('co.uri', 'cr.objecturi')))
+			->execute();
+
+		return $stmt->fetchAll();
+	}
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/NotificationProvider/EmailProvider.php b/apps/dav/lib/CalDAV/Reminder/NotificationProvider/EmailProvider.php
new file mode 100644
index 00000000000..81d4474011c
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/NotificationProvider/EmailProvider.php
@@ -0,0 +1,157 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Reminder\NotificationProvider;
+
+use OCA\DAV\CalDAV\Reminder\AbstractNotificationProvider;
+use OCP\IConfig;
+use OCP\ILogger;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory as L10NFactory;
+use OCP\Mail\IEMailTemplate;
+use OCP\Mail\IMailer;
+use OCP\IUser;
+use Sabre\VObject\Component\VCalendar;
+
+class EmailProvider extends AbstractNotificationProvider
+{
+	/** @var IMailer */
+	private $mailer;
+
+	public const NOTIFICATION_TYPE = 'EMAIL';
+
+	/**
+	 * @param IConfig $config
+	 * @param IMailer $mailer
+	 * @param ILogger $logger
+	 * @param L10NFactory $l10nFactory
+	 * @param IUrlGenerator $urlGenerator
+	 */
+	public function __construct(IConfig $config, IMailer $mailer, ILogger $logger,
+								L10NFactory $l10nFactory,
+								IURLGenerator $urlGenerator) {
+		parent::__construct($logger, $l10nFactory, $urlGenerator, $config);
+		$this->mailer = $mailer;
+	}
+
+	/**
+	 * Send notification
+	 *
+	 * @param VCalendar $vcalendar
+	 * @param string $calendarDisplayName
+	 * @param IUser $user
+	 * @return void
+	 * @throws \Exception
+	 */
+	public function send(VCalendar $vcalendar, string $calendarDisplayName, IUser $user): void
+	{
+		if ($user->getEMailAddress() === null) {
+			return;
+		}
+
+		$lang = $this->config->getUserValue($user->getUID(), 'core', 'lang', $this->l10nFactory->findLanguage());
+		$this->l10n = $this->l10nFactory->get('dav', $lang);
+
+		$event = $this->extractEventDetails($vcalendar);
+		$fromEMail = \OCP\Util::getDefaultEmailAddress('invitations-noreply');
+
+		$message = $this->mailer->createMessage()
+			->setFrom([$fromEMail => 'Nextcloud'])
+			// TODO: Set reply to from event creator
+			// ->setReplyTo([$sender => $senderName])
+			->setTo([$user->getEMailAddress() => $user->getDisplayName()]);
+
+		$template = $this->mailer->createEMailTemplate('dav.calendarReminder', $event);
+		$template->addHeader();
+
+		$this->addSubjectAndHeading($template, $event['title']);
+		$this->addBulletList($template, $event, $calendarDisplayName);
+
+		$template->addFooter();
+		$message->useTemplate($template);
+
+		$attachment = $this->mailer->createAttachment(
+			$vcalendar->serialize(),
+			$event['uid'].'.ics',// TODO(leon): Make file name unique, e.g. add event id
+			'text/calendar'
+		);
+		$message->attach($attachment);
+
+		try {
+			$failed = $this->mailer->send($message);
+			if ($failed) {
+				$this->logger->error('Unable to deliver message to {failed}', ['app' => 'dav', 'failed' =>  implode(', ', $failed)]);
+			}
+		} catch(\Exception $ex) {
+			$this->logger->logException($ex, ['app' => 'dav']);
+		}
+	}
+
+	/**
+	 * @param IEMailTemplate $template
+	 * @param string $summary
+	 */
+	private function addSubjectAndHeading(IEMailTemplate $template, string $summary): void
+	{
+		$template->setSubject('Notification: ' . $summary);
+		$template->addHeading($summary);
+	}
+
+	/**
+	 * @param IEMailTemplate $template
+	 * @param array $eventData
+	 * @param string $calendarDisplayName
+	 */
+	private function addBulletList(IEMailTemplate $template, array $eventData, string $calendarDisplayName): void
+	{
+		$template->addBodyListItem($calendarDisplayName, $this->l10n->t('Calendar:'),
+			$this->getAbsoluteImagePath('actions/info.svg'));
+
+		$template->addBodyListItem($eventData['when'], $this->l10n->t('Date:'),
+			$this->getAbsoluteImagePath('places/calendar.svg'));
+
+		if ($eventData['location']) {
+			$template->addBodyListItem((string) $eventData['location'], $this->l10n->t('Where:'),
+				$this->getAbsoluteImagePath('actions/address.svg'));
+		}
+		if ($eventData['description']) {
+			$template->addBodyListItem((string) $eventData['description'], $this->l10n->t('Description:'),
+				$this->getAbsoluteImagePath('actions/more.svg'));
+		}
+		if ($eventData['url']) {
+			$template->addBodyListItem((string) $eventData['url'], $this->l10n->t('Link:'),
+				$this->getAbsoluteImagePath('places/link.svg'));
+		}
+    }
+
+    /**
+	 * @param string $path
+	 * @return string
+	 */
+	private function getAbsoluteImagePath($path): string
+	{
+		return $this->urlGenerator->getAbsoluteURL(
+			$this->urlGenerator->imagePath('core', $path)
+		);
+	}
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/NotificationProvider/ProviderNotAvailableException.php b/apps/dav/lib/CalDAV/Reminder/NotificationProvider/ProviderNotAvailableException.php
new file mode 100644
index 00000000000..bf736db8a34
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/NotificationProvider/ProviderNotAvailableException.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Reminder\NotificationProvider;
+
+class ProviderNotAvailableException extends \Exception {
+
+	/**
+	 * ProviderNotAvailableException constructor.
+	 *
+	 * @since 16.0.0
+	 *
+	 * @param string $type ReminderType
+	 */
+	public function __construct(string $type) {
+		parent::__construct("No notification provider for type $type available");
+	}
+
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/NotificationProvider/PushProvider.php b/apps/dav/lib/CalDAV/Reminder/NotificationProvider/PushProvider.php
new file mode 100644
index 00000000000..1bb0e5c68b1
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/NotificationProvider/PushProvider.php
@@ -0,0 +1,101 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Reminder\NotificationProvider;
+
+use OCA\DAV\AppInfo\Application;
+use OCA\DAV\CalDAV\Reminder\AbstractNotificationProvider;
+use OCP\IConfig;
+use OCP\ILogger;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory as L10NFactory;
+use OCP\Notification\IManager;
+use OCP\IUser;
+use OCP\Notification\INotification;
+use Sabre\VObject\Component\VCalendar;
+use OCP\AppFramework\Utility\ITimeFactory;
+
+class PushProvider extends AbstractNotificationProvider
+{
+
+	public const NOTIFICATION_TYPE = 'DISPLAY';
+
+    /**
+     * @var IManager
+     */
+	private $manager;
+
+	/**
+	 * @var ITimeFactory
+	 */
+	private $timeFactory;
+
+	/**
+	 * @param IConfig $config
+	 * @param IManager $manager
+	 * @param ILogger $logger
+	 * @param L10NFactory $l10nFactory
+	 * @param IUrlGenerator $urlGenerator
+	 * @param ITimeFactory $timeFactory
+	 */
+	public function __construct(IConfig $config, IManager $manager, ILogger $logger,
+								L10NFactory $l10nFactory,
+								IURLGenerator $urlGenerator, ITimeFactory $timeFactory) {
+		parent::__construct($logger, $l10nFactory, $urlGenerator, $config);
+		$this->manager = $manager;
+		$this->timeFactory = $timeFactory;
+    }
+
+	/**
+	 * Send notification
+	 *
+	 * @param VCalendar $vcalendar
+	 * @param string $calendarDisplayName
+	 * @param IUser $user
+	 * @return void
+	 * @throws \Exception
+	 */
+    public function send(VCalendar $vcalendar, string $calendarDisplayName, IUser $user): void
+    {
+
+		$lang = $this->config->getUserValue($user->getUID(), 'core', 'lang', $this->l10nFactory->findLanguage());
+		$this->l10n = $this->l10nFactory->get('dav', $lang);
+
+		$event = $this->extractEventDetails($vcalendar);
+		/** @var INotification $notification */
+		$notification = $this->manager->createNotification();
+		$notification->setApp(Application::APP_ID)
+			->setUser($user->getUID())
+			->setDateTime($this->timeFactory->getDateTime())
+			->setObject(Application::APP_ID, $event['uid']) // $type and $id
+			->setSubject('calendar_reminder', ['title' => $event['title'], 'start' => $event['start']->getTimestamp()]) // $subject and $parameters
+			->setMessage('calendar_reminder', [
+				'when' => $event['when'],
+				'description' => $event['description'],
+				'location' => $event['location'],
+				'calendar' => $calendarDisplayName
+			])
+		;
+		$this->manager->notify($notification);
+    }
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/NotificationProviderManager.php b/apps/dav/lib/CalDAV/Reminder/NotificationProviderManager.php
new file mode 100644
index 00000000000..389cbbd2bfa
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/NotificationProviderManager.php
@@ -0,0 +1,59 @@
+<?php
+/**
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\CalDAV\Reminder;
+
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\ProviderNotAvailableException;
+
+class NotificationProviderManager {
+
+    /** @var array */
+    private $providers = [];
+    /**
+     * @var string $type
+     * @return AbstractNotificationProvider
+     * @throws ProviderNotAvailableException
+     * @throws NotificationTypeDoesNotExistException
+     */
+    public function getProvider(string $type): AbstractNotificationProvider
+    {
+        if (in_array($type, ReminderService::REMINDER_TYPES, true)) {
+            if (isset($this->providers[$type])) {
+                return $this->providers[$type];
+            }
+            throw new ProviderNotAvailableException($type);
+        }
+        throw new NotificationTypeDoesNotExistException($type);
+    }
+
+	/**
+	 * @param string $providerClassName
+	 * @throws \OCP\AppFramework\QueryException
+	 */
+    public function registerProvider(string $providerClassName): void
+	{
+		$provider = \OC::$server->query($providerClassName);
+
+		if (!$provider instanceof AbstractNotificationProvider) {
+			throw new \InvalidArgumentException('Invalid notification provider registered');
+		}
+
+		$this->providers[$provider::NOTIFICATION_TYPE] = $provider;
+	}
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/NotificationTypeDoesNotExistException.php b/apps/dav/lib/CalDAV/Reminder/NotificationTypeDoesNotExistException.php
new file mode 100644
index 00000000000..ae4ec3bd3b7
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/NotificationTypeDoesNotExistException.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Reminder;
+
+class NotificationTypeDoesNotExistException extends \Exception {
+
+	/**
+	 * NotificationTypeDoesNotExistException constructor.
+	 *
+	 * @since 16.0.0
+	 *
+	 * @param string $type ReminderType
+	 */
+	public function __construct(string $type) {
+		parent::__construct("Type $type is not an accepted type of notification");
+	}
+
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/Notifier.php b/apps/dav/lib/CalDAV/Reminder/Notifier.php
new file mode 100644
index 00000000000..d95774e019e
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/Notifier.php
@@ -0,0 +1,143 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Reminder;
+
+use OCA\DAV\AppInfo\Application;
+use OCP\IL10N;
+use OCP\L10N\IFactory;
+use OCP\Notification\INotification;
+use OCP\Notification\INotifier;
+use OCP\IURLGenerator;
+
+class Notifier implements INotifier {
+
+	public static $units = array(
+        'y' => 'year',
+        'm' => 'month',
+        'd' => 'day',
+        'h' => 'hour',
+        'i' => 'minute',
+        's' => 'second',
+    );
+
+	/** @var IFactory */
+	protected $factory;
+
+	/** @var IURLGenerator */
+	protected $urlGenerator;
+
+	/** @var IL10N */
+	protected $l;
+
+	public function __construct(IFactory $factory, IURLGenerator $urlGenerator) {
+		$this->factory = $factory;
+		$this->urlGenerator = $urlGenerator;
+	}
+
+	/**
+	 * @param INotification $notification
+	 * @param string $languageCode The code of the language that should be used to prepare the notification
+	 * @return INotification
+	 * @throws \Exception
+	 */
+	public function prepare(INotification $notification, $languageCode): INotification
+	{
+		if ($notification->getApp() !== Application::APP_ID) {
+			throw new \InvalidArgumentException('Notification not from this app');
+		}
+
+		// Read the language from the notification
+		$this->l = $this->factory->get('dav', $languageCode);
+
+		if ($notification->getSubject() === 'calendar_reminder') {
+			$subjectParameters = $notification->getSubjectParameters();
+			$notification->setParsedSubject($this->processEventTitle($subjectParameters));
+
+			$messageParameters = $notification->getMessageParameters();
+			$notification->setParsedMessage($this->processEventDescription($messageParameters));
+			$notification->setIcon($this->urlGenerator->getAbsoluteURL($this->urlGenerator->imagePath('core', 'places/calendar.svg')));
+			return $notification;
+		}
+		// Unknown subject => Unknown notification => throw
+		throw new \InvalidArgumentException('Unknown subject');
+	}
+
+	/**
+	 * @param array $event
+	 * @return string
+	 * @throws \Exception
+	 */
+	private function processEventTitle(array $event): string
+	{
+		$event_datetime = new \DateTime();
+		$event_datetime->setTimestamp($event['start']);
+		$now = new \DateTime();
+
+		$diff = $event_datetime->diff($now);
+
+		foreach (self::$units as $attribute => $unit) {
+            $count = $diff->$attribute;
+            if (0 !== $count) {
+                return $this->getPluralizedTitle($count, $diff->invert, $unit, $event['title']);
+            }
+        }
+        return '';
+	}
+
+	/**
+	 *
+	 * @param int $count
+	 * @param int $invert
+	 * @param string $unit
+	 * @param string $title
+	 * @return string
+	 */
+	private function getPluralizedTitle(int $count, int $invert, string $unit, string $title): string
+	{
+		if ($invert) {
+			return $this->l->n('%s (in one %s)', '%s (in %n %ss)', $count, [$title, $unit]);
+		}
+		// This should probably not show up
+		return $this->l->n('%s (one %s ago)', '%s (%n %ss ago)', $count, [$title, $unit]);
+	}
+
+	/**
+	 * @param array $event
+	 * @return string
+	 */
+	private function processEventDescription(array $event): string
+	{
+		$description = [
+			$this->l->t('Calendar: %s', $event['calendar']),
+			$this->l->t('Date: %s', $event['when']),
+		];
+
+		if ($event['description']) {
+			$description[] = $this->l->t('Description: %s', $event['description']);
+		}
+		if ($event['location']) {
+			$description[] = $this->l->t('Where: %s', $event['location']);
+		}
+		return implode('<br>', $description);
+	}
+}
diff --git a/apps/dav/lib/CalDAV/Reminder/ReminderService.php b/apps/dav/lib/CalDAV/Reminder/ReminderService.php
new file mode 100644
index 00000000000..87c2ce10673
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Reminder/ReminderService.php
@@ -0,0 +1,185 @@
+<?php
+/**
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\CalDAV\Reminder;
+
+use OC\User\NoUserException;
+use OCP\IGroup;
+use OCP\IGroupManager;
+use OCP\IUserManager;
+use OCP\IUserSession;
+use Sabre\VObject;
+use Sabre\VObject\Component\VAlarm;
+use Sabre\VObject\Reader;
+
+class ReminderService {
+
+    /** @var Backend */
+    private $backend;
+
+    /** @var NotificationProviderManager */
+    private $notificationProviderManager;
+
+	/** @var IUserManager */
+	private $userManager;
+
+	/** @var IGroupManager */
+	private $groupManager;
+
+	/** @var IUserSession */
+	private $userSession;
+
+	public const REMINDER_TYPE_EMAIL = 'EMAIL';
+	public const REMINDER_TYPE_DISPLAY = 'DISPLAY';
+	public const REMINDER_TYPE_AUDIO = 'AUDIO';
+
+	public const REMINDER_TYPES = [self::REMINDER_TYPE_EMAIL, self::REMINDER_TYPE_DISPLAY, self::REMINDER_TYPE_AUDIO];
+
+    public function __construct(Backend $backend,
+                                NotificationProviderManager $notificationProviderManager,
+								IUserManager $userManager,
+								IGroupManager $groupManager,
+								IUserSession $userSession) {
+        $this->backend = $backend;
+        $this->notificationProviderManager = $notificationProviderManager;
+		$this->userManager = $userManager;
+		$this->groupManager = $groupManager;
+		$this->userSession = $userSession;
+    }
+
+	/**
+	 * Process reminders to activate
+	 *
+	 * @throws NoUserException
+	 * @throws NotificationProvider\ProviderNotAvailableException
+	 * @throws NotificationTypeDoesNotExistException
+	 */
+    public function processReminders(): void
+    {
+
+        $reminders = $this->backend->getRemindersToProcess();
+
+		foreach ($reminders as $reminder) {
+			$calendarData = Reader::read($reminder['calendardata']);
+
+			$user = $this->userManager->get($reminder['uid']);
+
+            if ($user === null) {
+				throw new NoUserException('User not found for calendar');
+			}
+
+			$notificationProvider = $this->notificationProviderManager->getProvider($reminder['type']);
+			$notificationProvider->send($calendarData, $reminder['displayname'], $user);
+			$this->backend->removeReminder($reminder['id']);
+		}
+    }
+
+	/**
+	 * Saves reminders when a calendar object with some alarms was created/updated/deleted
+	 *
+	 * @param string $action
+	 * @param array $calendarData
+	 * @param array $shares
+	 * @param array $objectData
+	 * @return void
+	 * @throws VObject\InvalidDataException
+	 * @throws NoUserException
+	 */
+	public function onTouchCalendarObject(string $action, array $calendarData, array $shares, array $objectData): void
+	{
+		if (!isset($calendarData['principaluri'])) {
+			return;
+		}
+
+		// Always remove existing reminders for this event
+		$this->backend->cleanRemindersForEvent($objectData['calendarid'], $objectData['uri']);
+
+		/**
+		 * If we are deleting the event, no need to go further
+		 */
+		if ($action === '\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject') {
+			return;
+		}
+
+		$user = $this->userSession->getUser();
+
+		if ($user === null) {
+			throw new NoUserException('No user in session');
+		}
+
+		$users = $this->getUsersForShares($shares);
+
+		$users[] = $user->getUID();
+
+		$vobject = VObject\Reader::read($objectData['calendardata']);
+
+		foreach ($vobject->VEVENT->VALARM as $alarm) {
+			if ($alarm instanceof VAlarm) {
+				$type = strtoupper($alarm->ACTION->getValue());
+				if (in_array($type, self::REMINDER_TYPES, true)) {
+					$time = $alarm->getEffectiveTriggerTime();
+
+					foreach ($users as $uid) {
+						$this->backend->insertReminder(
+							$uid,
+							$objectData['calendarid'],
+							$objectData['uri'],
+							$type,
+							$time->getTimestamp(),
+							$vobject->VEVENT->DTSTART->getDateTime()->getTimestamp());
+
+					}
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * Get all users that have access to a given calendar
+	 *
+	 * @param array $shares
+	 * @return string[]
+	 */
+	private function getUsersForShares(array $shares): array
+	{
+		$users = $groups = [];
+		foreach ($shares as $share) {
+			$principal = explode('/', $share['{http://owncloud.org/ns}principal']);
+			if ($principal[1] === 'users') {
+				$users[] = $principal[2];
+			} else if ($principal[1] === 'groups') {
+				$groups[] = $principal[2];
+			}
+		}
+
+		if (!empty($groups)) {
+			foreach ($groups as $gid) {
+				$group = $this->groupManager->get($gid);
+				if ($group instanceof IGroup) {
+					foreach ($group->getUsers() as $user) {
+						$users[] = $user->getUID();
+					}
+				}
+			}
+		}
+
+		return array_unique($users);
+	}
+}
diff --git a/apps/dav/lib/Migration/Version1007Date20181005133326.php b/apps/dav/lib/Migration/Version1007Date20181005133326.php
new file mode 100644
index 00000000000..1e4cce950ac
--- /dev/null
+++ b/apps/dav/lib/Migration/Version1007Date20181005133326.php
@@ -0,0 +1,82 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OCA\DAV\Migration;
+
+use Closure;
+use OCP\DB\ISchemaWrapper;
+use OCP\Migration\SimpleMigrationStep;
+use OCP\Migration\IOutput;
+use Doctrine\DBAL\Types\Type;
+
+/**
+ * Auto-generated migration step: Please modify to your needs!
+ */
+class Version1007Date20181005133326 extends SimpleMigrationStep {
+
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 */
+	public function preSchemaChange(IOutput $output, Closure $schemaClosure, array $options) {
+	}
+
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 * @return null|ISchemaWrapper
+	 */
+	public function changeSchema(IOutput $output, Closure $schemaClosure, array $options) {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+
+		if (!$schema->hasTable('calendar_reminders')) {
+			$table = $schema->createTable('calendar_reminders');
+
+			$table->addColumn('id', Type::BIGINT, [
+				'autoincrement' => true,
+				'notnull' => true,
+				'length' => 11,
+				'unsigned' => true,
+			]);
+			$table->addColumn('uid', Type::STRING, [
+				'notnull' => true,
+				'length' => 255,
+			]);
+			$table->addColumn('calendarid', Type::BIGINT, [
+				'notnull' => false,
+				'length' => 11,
+			]);
+			$table->addColumn('objecturi', Type::STRING, [
+				'notnull' => true,
+				'length' => 255,
+			]);
+			$table->addColumn('type', Type::STRING, [
+				'notnull' => true,
+				'length' => 255,
+			]);
+			$table->addColumn('notificationdate', Type::DATETIME, [
+				'notnull' => false,
+			]);
+			$table->addColumn('eventstartdate', Type::DATETIME, [
+				'notnull' => false,
+			]);
+
+			$table->setPrimaryKey(['id']);
+			$table->addIndex(['calendarid'], 'calendar_reminder_calendars');
+
+			return $schema;
+		}
+	}
+
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 */
+	public function postSchemaChange(IOutput $output, Closure $schemaClosure, array $options) {
+	}
+}
diff --git a/apps/dav/lib/Settings/CalDAVSettings.php b/apps/dav/lib/Settings/CalDAVSettings.php
index f38143b5b4e..958c463b1d3 100644
--- a/apps/dav/lib/Settings/CalDAVSettings.php
+++ b/apps/dav/lib/Settings/CalDAVSettings.php
@@ -48,6 +48,7 @@ class CalDAVSettings implements ISettings {
 		$parameters = [
 			'send_invitations' => $this->config->getAppValue('dav', 'sendInvitations', 'yes'),
 			'generate_birthday_calendar' => $this->config->getAppValue('dav', 'generateBirthdayCalendar', 'yes'),
+			'send_reminders_notifications' => $this->config->getAppValue('dav', 'sendEventReminders', 'yes'),
 		];
 
 		return new TemplateResponse('dav', 'settings-admin-caldav', $parameters);
diff --git a/apps/dav/templates/settings-admin-caldav.php b/apps/dav/templates/settings-admin-caldav.php
index 87b159923d2..ba55a884702 100644
--- a/apps/dav/templates/settings-admin-caldav.php
+++ b/apps/dav/templates/settings-admin-caldav.php
@@ -72,4 +72,25 @@ script('dav', [
 		<em><?php p($l->t('Birthday calendars will be generated by a background job.')); ?></em><br>
 		<em><?php p($l->t('Hence they will not be available immediately after enabling but will show up after some time.')); ?></em>
 	</p>
+	<p>
+		<input type="checkbox" name="caldav_send_reminders_notifications" id="caldavSendRemindersNotifications" class="checkbox"
+			<?php ($_['send_reminders_notifications'] === 'yes') ? print_unescaped('checked="checked"') : null ?>/>
+		<label for="caldavSendRemindersNotifications"><?php p($l->t('Send notifications for events')); ?></label>
+		<br>
+		<em>
+			<?php print_unescaped(str_replace(
+				[
+					'{emailopen}',
+					'{linkclose}',
+				],
+				[
+					'<a href="../admin#mail_general_settings">',
+					'</a>',
+				],
+				$l->t('Please make sure to properly set up {emailopen}the email server{linkclose}.')
+			)); ?>
+		</em>
+		<br>
+		<em><?php p($l->t('Notifications will be send through background jobs, so these need to happen often enough.')); ?></em>
+	</p>
 </form>
diff --git a/apps/dav/tests/unit/BackgroundJob/EventReminderJobTest.php b/apps/dav/tests/unit/BackgroundJob/EventReminderJobTest.php
new file mode 100644
index 00000000000..960dd481dd2
--- /dev/null
+++ b/apps/dav/tests/unit/BackgroundJob/EventReminderJobTest.php
@@ -0,0 +1,68 @@
+<?php
+declare(strict_types=1);
+/**
+ * @copyright 2018, Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\DAV\Tests\unit\BackgroundJob;
+
+use OCA\DAV\BackgroundJob\EventReminderJob;
+use OCA\DAV\CalDAV\Reminder\ReminderService;
+use OCP\IConfig;
+use Test\TestCase;
+
+class EventReminderJobTest extends TestCase {
+
+	/** @var ReminderService|\PHPUnit\Framework\MockObject\MockObject */
+	private $reminderService;
+
+	/** @var IConfig|\PHPUnit\Framework\MockObject\MockObject */
+	private $config;
+
+	/** @var EventReminderJob|\PHPUnit\Framework\MockObject\MockObject */
+	private $backgroundJob;
+
+	protected function setUp() {
+		parent::setUp();
+
+		$this->reminderService = $this->createMock(ReminderService::class);
+		$this->config = $this->createMock(IConfig::class);
+
+		$this->backgroundJob = new EventReminderJob($this->reminderService, $this->config);
+	}
+
+	public function data(): array
+	{
+		return [[true], [false]];
+	}
+
+	/**
+	 * @dataProvider data
+	 * @param bool $sendEventReminders
+	 */
+	public function testRun(bool $sendEventReminders): void
+	{
+		$this->config->expects($this->once())->method('getAppValue')->with('dav', 'sendEventReminders', 'yes')->willReturn($sendEventReminders ? 'yes' : 'no');
+		$this->reminderService->expects($this->exactly($sendEventReminders ? 1 : 0))->method('processReminders');
+
+		$this->backgroundJob->run([]);
+	}
+}
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/AbstractNotificationProviderTest.php b/apps/dav/tests/unit/CalDAV/Reminder/AbstractNotificationProviderTest.php
new file mode 100644
index 00000000000..ba2e54af33c
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Reminder/AbstractNotificationProviderTest.php
@@ -0,0 +1,87 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019, Thomas Citharel
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\Tests\unit\CalDAV\Reminder;
+
+use OCA\DAV\CalDAV\Reminder\AbstractNotificationProvider;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\ILogger;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory as L10NFactory;
+use OCP\IUser;
+use Test\TestCase;
+use Sabre\VObject\Component\VCalendar;
+
+abstract class AbstractNotificationProviderTest extends TestCase {
+
+    /** @var ILogger|\PHPUnit\Framework\MockObject\MockObject */
+    protected $logger;
+
+    /** @var L10NFactory|\PHPUnit\Framework\MockObject\MockObject */
+    protected $l10nFactory;
+
+    /** @var IL10N|\PHPUnit\Framework\MockObject\MockObject */
+    protected $l10n;
+
+    /** @var IURLGenerator|\PHPUnit\Framework\MockObject\MockObject */
+    protected $urlGenerator;
+
+    /** @var IConfig|\PHPUnit\Framework\MockObject\MockObject */
+    protected $config;
+
+    /** @var AbstractNotificationProvider|\PHPUnit\Framework\MockObject\MockObject */
+    protected $provider;
+
+	/**
+	 * @var VCalendar
+	 */
+	protected $vcalendar;
+
+	/**
+	 * @var string
+	 */
+	protected $calendarDisplayName;
+
+	/**
+	 * @var IUser|\PHPUnit\Framework\MockObject\MockObject
+	 */
+	protected $user;
+
+	public function setUp() {
+		parent::setUp();
+
+        $this->logger = $this->createMock(ILogger::class);
+        $this->l10nFactory = $this->createMock(L10NFactory::class);
+        $this->l10n = $this->createMock(IL10N::class);
+        $this->urlGenerator = $this->createMock(IURLGenerator::class);
+        $this->config = $this->createMock(IConfig::class);
+
+        $this->vcalendar = new VCalendar();
+		$this->vcalendar->add('VEVENT', [
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2017-01-01 00:00:00') // 1483228800
+        ]);
+		$this->calendarDisplayName = 'Personal';
+
+        $this->user = $this->createMock(IUser::class);
+    }
+}
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/BackendTest.php b/apps/dav/tests/unit/CalDAV/Reminder/BackendTest.php
new file mode 100644
index 00000000000..1cd979dc5d9
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Reminder/BackendTest.php
@@ -0,0 +1,313 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018, Thomas Citharel
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\Tests\unit\CalDAV\Reminder;
+
+use OCP\IDBConnection;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCA\DAV\CalDAV\Reminder\Backend as ReminderBackend;
+use Test\TestCase;
+
+class BackendTest extends TestCase {
+
+    /**
+     * Reminder Backend
+     *
+     * @var ReminderBackend|\PHPUnit\Framework\MockObject\MockObject
+     */
+    private $reminderBackend;
+
+    /** @var IDBConnection|\PHPUnit\Framework\MockObject\MockObject */
+	private $dbConnection;
+
+	/** @var ITimeFactory|\PHPUnit\Framework\MockObject\MockObject */
+    private $timeFactory;
+
+    public function setUp() {
+		parent::setUp();
+
+		$this->dbConnection = $this->createMock(IDBConnection::class);
+		$this->timeFactory = $this->createMock(ITimeFactory::class);
+        $this->reminderBackend = new ReminderBackend($this->dbConnection, $this->timeFactory);
+    }
+
+    public function testCleanRemindersForEvent(): void
+    {
+		/** @var IQueryBuilder|\PHPUnit\Framework\MockObject\MockObject $queryBuilder */
+        $queryBuilder = $this->createMock(IQueryBuilder::class);
+        $stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
+		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
+
+		$this->dbConnection->expects($this->once())
+			->method('getQueryBuilder')
+			->with()
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->method('expr')
+			->will($this->returnValue($expr));
+
+		$expr->method('eq')
+			->will($this->returnValueMap([
+				['calendarid', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
+				['objecturi', 'createNamedParameter-2', null, 'WHERE_CLAUSE_2'],
+			]));
+		$queryBuilder->method('createNamedParameter')
+			->will($this->returnValueMap([
+				[1, \PDO::PARAM_STR, null, 'createNamedParameter-1'],
+				['object.ics', \PDO::PARAM_STR, null, 'createNamedParameter-2'],
+			]));
+
+		$queryBuilder->expects($this->at(0))
+			->method('delete')
+			->with('calendar_reminders')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(3))
+			->method('where')
+			->with('WHERE_CLAUSE_1')
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->expects($this->at(6))
+			->method('andWhere')
+			->with('WHERE_CLAUSE_2')
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->expects($this->at(7))
+			->method('execute')
+			->with()
+			->willReturn($stmt);
+
+		$this->reminderBackend->cleanRemindersForEvent(1, 'object.ics');
+	}
+
+	public function testCleanRemindersForCalendar(): void
+    {
+		/** @var IQueryBuilder|\PHPUnit\Framework\MockObject\MockObject $queryBuilder */
+        $queryBuilder = $this->createMock(IQueryBuilder::class);
+        $stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
+		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
+
+		$this->dbConnection->expects($this->once())
+			->method('getQueryBuilder')
+			->with()
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->method('expr')
+			->will($this->returnValue($expr));
+
+		$expr->method('eq')
+			->will($this->returnValueMap([
+				['calendarid', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
+			]));
+		$queryBuilder->method('createNamedParameter')
+			->will($this->returnValueMap([
+				[1337, \PDO::PARAM_STR, null, 'createNamedParameter-1'],
+			]));
+
+		$queryBuilder->expects($this->at(0))
+			->method('delete')
+			->with('calendar_reminders')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(3))
+			->method('where')
+			->with('WHERE_CLAUSE_1')
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->expects($this->at(4))
+			->method('execute')
+			->with()
+			->willReturn($stmt);
+
+		$this->reminderBackend->cleanRemindersForCalendar(1337);
+	}
+
+	public function testRemoveReminder(): void
+	{
+		/** @var IQueryBuilder|\PHPUnit\Framework\MockObject\MockObject $queryBuilder */
+        $queryBuilder = $this->createMock(IQueryBuilder::class);
+        $stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
+		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
+
+		$this->dbConnection->expects($this->once())
+			->method('getQueryBuilder')
+			->with()
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->method('expr')
+			->will($this->returnValue($expr));
+
+		$expr->method('eq')
+			->will($this->returnValueMap([
+				['id', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
+			]));
+		$queryBuilder->method('createNamedParameter')
+			->will($this->returnValueMap([
+				[16, \PDO::PARAM_STR, null, 'createNamedParameter-1'],
+			]));
+
+		$queryBuilder->expects($this->at(0))
+			->method('delete')
+			->with('calendar_reminders')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(3))
+			->method('where')
+			->with('WHERE_CLAUSE_1')
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->expects($this->at(4))
+			->method('execute')
+			->with()
+			->willReturn($stmt);
+
+		$this->reminderBackend->removeReminder(16);
+	}
+
+	public function testGetRemindersToProcess(): void
+    {
+		$dbData = [[
+				'cr.id' => 30,
+				'cr.calendarid' => 3,
+				'cr.objecturi' => 'object.ics',
+				'cr.type' => 'EMAIL',
+				'cr.notificationdate' => 1337,
+				'cr.uid' => 'user1',
+				'co.calendardata' => 'BEGIN:VCALENDAR',
+				'c.displayname' => 'My Calendar'
+			]];
+
+		$this->timeFactory->expects($this->exactly(2))
+			->method('getTime')
+			->with()
+			->willReturn(1337);
+
+		/** @var IQueryBuilder|\PHPUnit\Framework\MockObject\MockObject $queryBuilder */
+        $queryBuilder = $this->createMock(IQueryBuilder::class);
+        $stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
+		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
+
+		$this->dbConnection->expects($this->once())
+			->method('getQueryBuilder')
+			->with()
+			->willReturn($queryBuilder);
+		$queryBuilder->method('expr')
+			->willReturn($expr);
+
+		$expr->method('eq')
+			->willReturnMap([
+				['cr.calendarid', 'c.id', null, 'EQ_CLAUSE_1'],
+				['co.uri', 'cr.objecturi', null, 'EQ_CLAUSE_2'],
+			]);
+		$expr->method('andX')
+			->willReturnMap([
+				['EQ_CLAUSE_1', 'EQ_CLAUSE_2', 'ANDX_CLAUSE'],
+			]);
+
+		$expr->method('lte')
+			->with('cr.notificationdate', 'createNamedParameter-1', null)
+			->willReturn('LTE_CLAUSE_1');
+
+		$expr->method('gte')
+			->with('cr.eventstartdate', 'createNamedParameter-1', null)
+			->willReturn('GTE_CLAUSE_2');
+
+		$queryBuilder->method('createNamedParameter')
+			->willReturnMap([
+				[1337, \PDO::PARAM_STR, null, 'createNamedParameter-1'],
+			]);
+
+		$queryBuilder->expects($this->at(0))
+			->method('select')
+			->with(['cr.id', 'cr.calendarid', 'cr.objecturi', 'cr.type', 'cr.notificationdate', 'cr.uid', 'co.calendardata', 'c.displayname'])
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(1))
+			->method('from')
+			->with('calendar_reminders', 'cr')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(4))
+			->method('where')
+			->with('LTE_CLAUSE_1')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(7))
+			->method('andWhere')
+			->with('GTE_CLAUSE_2')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(9))
+			->method('leftJoin')
+			->with('cr', 'calendars', 'c', 'EQ_CLAUSE_1')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(13))
+			->method('leftJoin')
+			->with('cr', 'calendarobjects', 'co', 'ANDX_CLAUSE')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(14))
+			->method('execute')
+			->with()
+			->willReturn($stmt);
+
+		$stmt->expects($this->once())
+			->method('fetchAll')
+			->with()
+			->willReturn($dbData);
+
+		$actual = $this->reminderBackend->getRemindersToProcess();
+		$this->assertEquals($dbData, $actual);
+	}
+
+	public function testInsertReminder(): void
+    {
+		/** @var IQueryBuilder|\PHPUnit\Framework\MockObject\MockObject $queryBuilder */
+        $queryBuilder = $this->createMock(IQueryBuilder::class);
+        $stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
+		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
+
+		$this->dbConnection->expects($this->once())
+			->method('getQueryBuilder')
+			->with()
+			->will($this->returnValue($queryBuilder));
+		$queryBuilder->method('expr')
+			->will($this->returnValue($expr));
+
+		$queryBuilder->method('createNamedParameter')
+			->will($this->returnValueMap([
+				['user1', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
+				['1', \PDO::PARAM_STR, null, 'createNamedParameter-2'],
+				['object.ics', \PDO::PARAM_STR, null, 'createNamedParameter-3'],
+				['EMAIL', \PDO::PARAM_STR, null, 'createNamedParameter-4'],
+				[1227, \PDO::PARAM_STR, null, 'createNamedParameter-5'],
+				[1337, \PDO::PARAM_STR, null, 'createNamedParameter-6'],
+			]));
+
+		$queryBuilder->expects($this->at(0))
+			->method('insert')
+			->with('calendar_reminders')
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(7))
+			->method('values')
+			->with([
+				'uid' => 'createNamedParameter-1',
+				'calendarid' => 'createNamedParameter-2',
+				'objecturi' => 'createNamedParameter-3',
+				'type' => 'createNamedParameter-4',
+				'notificationdate' => 'createNamedParameter-5',
+				'eventstartdate' => 'createNamedParameter-6',
+			])
+			->willReturn($queryBuilder);
+		$queryBuilder->expects($this->at(8))
+			->method('execute')
+			->with()
+			->willReturn($stmt);
+
+		$actual = $this->reminderBackend->insertReminder('user1', '1', 'object.ics', 'EMAIL', 1227, 1337);
+    }
+}
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/NotificationProvider/EmailProviderTest.php b/apps/dav/tests/unit/CalDAV/Reminder/NotificationProvider/EmailProviderTest.php
new file mode 100644
index 00000000000..34a61b34fc5
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Reminder/NotificationProvider/EmailProviderTest.php
@@ -0,0 +1,226 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019, Thomas Citharel
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\Tests\unit\CalDAV\Reminder\NotificationProvider;
+
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\EmailProvider;
+use OCA\DAV\CalDAV\Reminder\AbstractNotificationProvider;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\ILogger;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory as L10NFactory;
+use OCP\IUser;
+use OCP\Mail\IEMailTemplate;
+use OCP\Mail\IMailer;
+use OCP\Mail\IAttachment;
+use OCP\Mail\IMessage;
+use Test\TestCase;
+use OCA\DAV\Tests\unit\CalDAV\Reminder\AbstractNotificationProviderTest;
+
+class EmailProviderTest extends AbstractNotificationProviderTest {
+
+    const USER_EMAIL = 'frodo@hobb.it';
+
+    /** @var ILogger|\PHPUnit\Framework\MockObject\MockObject */
+    protected $logger;
+
+    /** @var L10NFactory|\PHPUnit\Framework\MockObject\MockObject */
+    protected $l10nFactory;
+
+    /** @var IL10N|\PHPUnit\Framework\MockObject\MockObject */
+    protected $l10n;
+
+    /** @var IURLGenerator|\PHPUnit\Framework\MockObject\MockObject */
+    protected $urlGenerator;
+
+    /** @var IConfig|\PHPUnit\Framework\MockObject\MockObject */
+    protected $config;
+
+    /** @var IMailer|\PHPUnit\Framework\MockObject\MockObject */
+	private $mailer;
+
+    public function setUp() {
+        parent::setUp();
+
+        $this->mailer = $this->createMock(IMailer::class);
+
+        $this->provider = new EmailProvider(
+            $this->config,
+            $this->mailer,
+            $this->logger,
+            $this->l10nFactory,
+            $this->urlGenerator
+        );
+    }
+
+    public function testSendWithNoUserEmail(): void
+    {
+        $this->user->expects($this->once())
+            ->method('getEMailAddress')
+            ->with()
+            ->willReturn(null);
+
+        $this->mailer
+            ->expects($this->never())
+            ->method('send');
+
+        $this->provider->send($this->vcalendar, $this->calendarDisplayName, $this->user);
+    }
+
+    public function testSendWithFailedRecipients(): void
+    {
+        $this->user->expects($this->exactly(2))
+            ->method('getEMailAddress')
+            ->with()
+            ->willReturn(self::USER_EMAIL);
+
+        $this->mailer
+            ->expects($this->once())
+            ->method('send')
+            ->willReturn([self::USER_EMAIL])
+        ;
+
+        $this->logger
+            ->expects($this->once())
+            ->method('error');
+
+        $l10n = $this->createMock(IL10N::class);
+        $this->l10nFactory
+            ->method('get')
+            ->willReturn($l10n);
+
+		$this->provider->send($this->vcalendar, $this->calendarDisplayName, $this->user);
+    }
+
+    public function testSendWithMailerFailure(): void
+    {
+        $this->user->expects($this->exactly(2))
+            ->method('getEMailAddress')
+            ->with()
+            ->willReturn(self::USER_EMAIL);
+
+        $ex = new \Exception();
+
+        $this->mailer
+            ->expects($this->once())
+            ->method('send')
+            ->will($this->throwException($ex))
+        ;
+
+        $this->logger
+            ->expects($this->once())
+            ->method('logException')
+            ->with($ex, ['app' => 'dav']);
+
+        $l10n = $this->createMock(IL10N::class);
+        $this->l10nFactory
+            ->method('get')
+            ->willReturn($l10n);
+
+		$this->provider->send($this->vcalendar, $this->calendarDisplayName, $this->user);
+    }
+
+    public function testSend(): void
+    {
+        $this->user->expects($this->exactly(2))
+            ->method('getEMailAddress')
+            ->with()
+            ->willReturn(self::USER_EMAIL);
+
+        $this->user->expects($this->once())
+            ->method('getDisplayName')
+            ->with()
+            ->willReturn('Frodo');
+
+        $this->urlGenerator
+            ->expects($this->exactly(2))
+            ->method('getAbsoluteURL');
+
+        $this->urlGenerator
+            ->expects($this->exactly(2))
+            ->method('imagePath');
+
+        $mailMessage = $this->createMock(IMessage::class);
+        $mailMessage->expects($this->once())
+            ->method('setFrom')
+            ->with([\OCP\Util::getDefaultEmailAddress('invitations-noreply') => 'Nextcloud'])
+            ->willReturn($mailMessage);
+
+        $mailMessage->expects($this->once())
+			->method('setTo')
+            ->with([self::USER_EMAIL => 'Frodo'])
+            ->willReturn($mailMessage);
+
+        $mailMessage
+            ->expects($this->never())
+            ->method('setReplyTo')
+            ->willReturn($mailMessage);
+
+		$emailTemplate = $this->createMock(IEMailTemplate::class);
+        $this->mailer
+            ->expects($this->once())
+            ->method('createEMailTemplate')
+            ->willReturn($emailTemplate);
+
+        $emailTemplate->expects($this->once())
+			->method('setSubject')
+            ->with('Notification: Fellowship meeting');
+
+        $emailTemplate->expects($this->once())
+            ->method('addHeader');
+
+        $emailTemplate->expects($this->once())
+            ->method('addHeading');
+
+        $emailTemplate->expects($this->exactly(2))
+            ->method('addBodyListItem');
+
+        $emailTemplate->expects($this->once())
+            ->method('addFooter');
+
+        $mailMessage->expects($this->once())
+            ->method('useTemplate')
+            ->with($emailTemplate);
+
+        $this->mailer
+            ->expects($this->once())
+            ->method('createMessage')
+            ->willReturn($mailMessage);
+
+        $emailAttachment = $this->createMock(IAttachment::class);
+        $this->mailer
+            ->expects($this->once())
+            ->method('createAttachment')
+            ->willReturn($emailAttachment);
+
+        $this->mailer
+            ->expects($this->once())
+            ->method('send');
+
+		$l10n = $this->createMock(IL10N::class);
+        $this->l10nFactory
+            ->method('get')
+            ->willReturn($l10n);
+
+		$this->provider->send($this->vcalendar, $this->calendarDisplayName, $this->user);
+    }
+}
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/NotificationProvider/PushProviderTest.php b/apps/dav/tests/unit/CalDAV/Reminder/NotificationProvider/PushProviderTest.php
new file mode 100644
index 00000000000..e10afb44d27
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Reminder/NotificationProvider/PushProviderTest.php
@@ -0,0 +1,139 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019, Thomas Citharel
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\Tests\unit\CalDAV\Reminder\NotificationProvider;
+
+use OCA\DAV\AppInfo\Application;
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\PushProvider;
+use OCA\DAV\CalDAV\Reminder\AbstractNotificationProvider;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\ILogger;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory as L10NFactory;
+use OCP\IUser;
+use OCP\Notification\IManager;
+use OCP\Notification\INotification;
+use OCP\AppFramework\Utility\ITimeFactory;
+use Test\TestCase;
+use OCA\DAV\Tests\unit\CalDAV\Reminder\AbstractNotificationProviderTest;
+
+class PushProviderTest extends AbstractNotificationProviderTest {
+
+    /** @var ILogger|\PHPUnit\Framework\MockObject\MockObject */
+    protected $logger;
+
+    /** @var L10NFactory|\PHPUnit\Framework\MockObject\MockObject */
+    protected $l10nFactory;
+
+    /** @var IL10N|\PHPUnit\Framework\MockObject\MockObject */
+    protected $l10n;
+
+    /** @var IURLGenerator|\PHPUnit\Framework\MockObject\MockObject */
+    protected $urlGenerator;
+
+    /** @var IConfig|\PHPUnit\Framework\MockObject\MockObject */
+    protected $config;
+
+    /** @var IManager|\PHPUnit\Framework\MockObject\MockObject */
+    private $manager;
+
+    /** @var ITimeFactory|\PHPUnit\Framework\MockObject\MockObject */
+    private $timeFactory;
+
+    public function setUp() {
+        parent::setUp();
+
+        $this->manager = $this->createMock(IManager::class);
+        $this->timeFactory = $this->createMock(ITimeFactory::class);
+
+        $this->provider = new PushProvider(
+            $this->config,
+            $this->manager,
+            $this->logger,
+            $this->l10nFactory,
+            $this->urlGenerator,
+            $this->timeFactory
+        );
+    }
+
+    public function testSend(): void
+    {
+        $notification = $this->createMock(INotification::class);
+        $notification
+            ->expects($this->once())
+            ->method('setApp')
+            ->with(Application::APP_ID)
+            ->willReturn($notification);
+
+        $notification
+            ->expects($this->once())
+            ->method('setUser')
+            ->willReturn($notification)
+        ;
+
+        $notification
+            ->expects($this->once())
+            ->method('setDateTime')
+            ->willReturn($notification)
+        ;
+
+        $notification
+            ->expects($this->once())
+            ->method('setObject')
+            ->willReturn($notification)
+        ;
+
+        $notification
+            ->expects($this->once())
+            ->method('setSubject')
+            ->willReturn($notification)
+        ;
+
+        $notification
+            ->expects($this->once())
+            ->method('setMessage')
+            ->willReturn($notification)
+        ;
+
+        $this->manager
+            ->expects($this->once())
+            ->method('createNotification')
+            ->willReturn($notification);
+
+        $this->manager
+            ->expects($this->once())
+            ->method('notify')
+            ->with($notification);
+
+        $l10n = $this->createMock(IL10N::class);
+        $this->l10nFactory
+            ->method('get')
+            ->willReturn($l10n);
+
+        $this->timeFactory->expects($this->once())
+			->method('getDateTime')
+			->with()
+			->willReturn(new \DateTime());
+
+		$this->provider->send($this->vcalendar, $this->calendarDisplayName, $this->user);
+    }
+}
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/NotificationProviderManagerTest.php b/apps/dav/tests/unit/CalDAV/Reminder/NotificationProviderManagerTest.php
new file mode 100644
index 00000000000..d962b631c10
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Reminder/NotificationProviderManagerTest.php
@@ -0,0 +1,100 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019, Thomas Citharel
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\Tests\unit\CalDAV\Reminder;
+
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\EmailProvider;
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\ProviderNotAvailableException;
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\PushProvider;
+use OCA\DAV\CalDAV\Reminder\NotificationProviderManager;
+use OCA\DAV\CalDAV\Reminder\NotificationTypeDoesNotExistException;
+use OCA\DAV\Capabilities;
+use Test\TestCase;
+
+class NotificationProviderManagerTest extends TestCase {
+
+    /** @var NotificationProviderManager|\PHPUnit\Framework\MockObject\MockObject */
+    private $providerManager;
+
+	/**
+	 * @throws \OCP\AppFramework\QueryException
+	 */
+	public function setUp() {
+		parent::setUp();
+
+        $this->providerManager = new NotificationProviderManager();
+        $this->providerManager->registerProvider(EmailProvider::class);
+    }
+
+	/**
+	 * @expectedException OCA\DAV\CalDAV\Reminder\NotificationTypeDoesNotExistException
+	 * @expectedExceptionMessage Type NOT EXISTENT is not an accepted type of notification
+	 * @throws ProviderNotAvailableException
+	 * @throws NotificationTypeDoesNotExistException
+	 */
+    public function testGetProviderForUnknownType(): void
+    {
+        $this->providerManager->getProvider('NOT EXISTENT');
+    }
+
+	/**
+	 * @expectedException OCA\DAV\CalDAV\Reminder\NotificationProvider\ProviderNotAvailableException
+	 * @expectedExceptionMessage No notification provider for type AUDIO available
+	 * @throws NotificationTypeDoesNotExistException
+	 * @throws ProviderNotAvailableException
+	 */
+    public function testGetProviderForUnRegisteredType(): void
+    {
+        $this->providerManager->getProvider('AUDIO');
+    }
+
+	/**
+	 * @throws NotificationTypeDoesNotExistException
+	 * @throws ProviderNotAvailableException
+	 */
+	public function testGetProvider(): void
+    {
+        $provider = $this->providerManager->getProvider('EMAIL');
+        $this->assertInstanceOf(EmailProvider::class, $provider);
+    }
+
+	/**
+	 * @throws NotificationTypeDoesNotExistException
+	 * @throws ProviderNotAvailableException
+	 * @throws \OCP\AppFramework\QueryException
+	 */
+	public function testRegisterProvider(): void
+	{
+		$this->providerManager->registerProvider(PushProvider::class);
+		$provider = $this->providerManager->getProvider('DISPLAY');
+		$this->assertInstanceOf(PushProvider::class, $provider);
+	}
+
+	/**
+	 * @expectedExceptionMessage Invalid notification provider registered
+	 * @expectedException \InvalidArgumentException
+	 * @throws \OCP\AppFramework\QueryException
+	 */
+	public function testRegisterBadProvider(): void
+	{
+		$this->providerManager->registerProvider(Capabilities::class);
+	}
+}
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/NotifierTest.php b/apps/dav/tests/unit/CalDAV/Reminder/NotifierTest.php
new file mode 100644
index 00000000000..b9695b33fdc
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Reminder/NotifierTest.php
@@ -0,0 +1,184 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019 Thomas Citharel <tcit@tcit.fr>
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\DAV\Tests\unit\CalDAV\Reminder;
+
+use OCA\DAV\AppInfo\Application;
+use OCA\DAV\CalDAV\Reminder\Notifier;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory;
+use OCP\Notification\INotification;
+use Test\TestCase;
+
+class NotifierTest extends TestCase {
+	/** @var Notifier */
+	protected $notifier;
+
+	/** @var IFactory|\PHPUnit\Framework\MockObject\MockObject */
+	protected $factory;
+	/** @var IURLGenerator|\PHPUnit\Framework\MockObject\MockObject */
+	protected $urlGenerator;
+	/** @var IL10N|\PHPUnit\Framework\MockObject\MockObject */
+	protected $l;
+
+	protected function setUp() {
+		parent::setUp();
+
+		$this->urlGenerator = $this->createMock(IURLGenerator::class);
+		$this->l = $this->createMock(IL10N::class);
+		$this->l->expects($this->any())
+			->method('t')
+			->willReturnCallback(function($string, $args) {
+				return vsprintf($string, $args);
+			});
+		$this->l->expects($this->any())
+			->method('n')
+			->willReturnCallback(function($textSingular, $textPlural, $count, $args) {
+				$text = $count === 1 ? $textSingular : $textPlural;
+				$text = str_replace('%n', (string)$count, $text);
+				return vsprintf($text, $args);
+			});
+		$this->factory = $this->createMock(IFactory::class);
+		$this->factory->expects($this->any())
+			->method('get')
+			->willReturn($this->l);
+
+		$this->notifier = new Notifier(
+			$this->factory,
+			$this->urlGenerator
+		);
+	}
+
+	/**
+	 * @expectedException \InvalidArgumentException
+	 * @expectedExceptionMessage Notification not from this app
+	 */
+	public function testPrepareWrongApp(): void
+	{
+		/** @var INotification|\PHPUnit\Framework\MockObject\MockObject $notification */
+		$notification = $this->createMock(INotification::class);
+
+		$notification->expects($this->once())
+			->method('getApp')
+			->willReturn('notifications');
+		$notification->expects($this->never())
+			->method('getSubject');
+
+		$this->notifier->prepare($notification, 'en');
+	}
+
+	/**
+	 * @expectedException \InvalidArgumentException
+	 * @expectedExceptionMessage Unknown subject
+	 */
+	public function testPrepareWrongSubject() {
+		/** @var INotification|\PHPUnit\Framework\MockObject\MockObject $notification */
+		$notification = $this->createMock(INotification::class);
+
+		$notification->expects($this->once())
+			->method('getApp')
+			->willReturn(Application::APP_ID);
+		$notification->expects($this->once())
+			->method('getSubject')
+			->willReturn('wrong subject');
+
+		$this->notifier->prepare($notification, 'en');
+	}
+
+	public function dataPrepare(): array
+	{
+		return [
+			[
+				'calendar_reminder',
+				[
+					'title' => 'foo',
+					'start' => time() - 60 * 60 * 24
+				],
+				'foo (one day ago)',
+				[
+					'when' => 'foo',
+					'description' => 'bar',
+					'location' => 'NC Headquarters',
+					'calendar' => 'Personal'
+				],
+				'Calendar: Personal<br>Date: foo<br>Description: bar<br>Where: NC Headquarters'
+			],
+		];
+	}
+
+	/**
+	 * @dataProvider dataPrepare
+	 *
+	 * @param string $subjectType
+	 * @param array $subjectParams
+	 * @param string $subject
+	 * @param array $messageParams
+	 * @param string $message
+	 * @throws \Exception
+	 */
+	public function testPrepare(string $subjectType, array $subjectParams, string $subject, array $messageParams, string $message): void
+	{
+		/** @var INotification|\PHPUnit\Framework\MockObject\MockObject $notification */
+		$notification = $this->createMock(INotification::class);
+
+		$notification->expects($this->once())
+			->method('getApp')
+			->willReturn(Application::APP_ID);
+		$notification->expects($this->once())
+			->method('getSubject')
+			->willReturn($subjectType);
+		$notification->expects($this->once())
+			->method('getSubjectParameters')
+			->willReturn($subjectParams);
+		$notification->expects($this->once())
+			->method('getMessageParameters')
+			->willReturn($messageParams);
+
+		$notification->expects($this->once())
+			->method('setParsedSubject')
+			->with($subject)
+			->willReturnSelf();
+
+		$notification->expects($this->once())
+			->method('setParsedMessage')
+			->with($message)
+			->willReturnSelf();
+
+		$this->urlGenerator->expects($this->once())
+			->method('imagePath')
+			->with('core', 'places/calendar.svg')
+			->willReturn('icon-url');
+		$this->urlGenerator->expects($this->once())
+			->method('getAbsoluteURL')
+			->with('icon-url')
+			->willReturn('absolute-icon-url');
+		$notification->expects($this->once())
+			->method('setIcon')
+			->with('absolute-icon-url')
+			->willReturnSelf();
+
+		$return = $this->notifier->prepare($notification, 'en');
+
+		$this->assertEquals($notification, $return);
+	}
+}
diff --git a/apps/dav/tests/unit/CalDAV/Reminder/ReminderServiceTest.php b/apps/dav/tests/unit/CalDAV/Reminder/ReminderServiceTest.php
new file mode 100644
index 00000000000..061c3f16e38
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Reminder/ReminderServiceTest.php
@@ -0,0 +1,276 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019, Thomas Citharel
+ *
+ * @author Thomas Citharel <tcit@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\Tests\unit\CalDAV\Reminder;
+
+use OCA\DAV\CalDAV\Reminder\AbstractNotificationProvider;
+use OCA\DAV\CalDAV\Reminder\Backend;
+use OCA\DAV\CalDAV\Reminder\NotificationProviderManager;
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\EmailProvider;
+use OCA\DAV\CalDAV\Reminder\NotificationProvider\PushProvider;
+use OCA\DAV\CalDAV\Reminder\ReminderService;
+use OCP\IGroup;
+use OCP\IGroupManager;
+use OCP\IUser;
+use OCP\IUserManager;
+use OCP\IUserSession;
+use Test\TestCase;
+
+class ReminderServiceTest extends TestCase {
+
+    /** @var Backend|\PHPUnit\Framework\MockObject\MockObject */
+    private $backend;
+
+    /** @var NotificationProviderManager|\PHPUnit\Framework\MockObject\MockObject */
+    private $notificationProviderManager;
+
+	/** @var IUserManager|\PHPUnit\Framework\MockObject\MockObject */
+	private $userManager;
+
+	/** @var IGroupManager|\PHPUnit\Framework\MockObject\MockObject*/
+	private $groupManager;
+
+	/** @var IUserSession|\PHPUnit\Framework\MockObject\MockObject */
+	private $userSession;
+
+	public const CALENDAR_DATA = <<<EOD
+BEGIN:VCALENDAR
+PRODID:-//Nextcloud calendar v1.6.4
+BEGIN:VEVENT
+CREATED:20160602T133732
+DTSTAMP:20160602T133732
+LAST-MODIFIED:20160602T133732
+UID:wej2z68l9h
+SUMMARY:Test Event
+LOCATION:Somewhere ...
+DESCRIPTION:maybe ....
+DTSTART;TZID=Europe/Berlin;VALUE=DATE:20160609
+DTEND;TZID=Europe/Berlin;VALUE=DATE:20160610
+BEGIN:VALARM
+ACTION:EMAIL
+TRIGGER:-PT15M
+END:VALARM
+END:VEVENT
+END:VCALENDAR
+EOD;
+
+    public function setUp() {
+		parent::setUp();
+
+        $this->backend = $this->createMock(Backend::class);
+        $this->notificationProviderManager = $this->createMock(NotificationProviderManager::class);
+        $this->userManager = $this->createMock(IUserManager::class);
+		$this->groupManager = $this->createMock(IGroupManager::class);
+		$this->userSession = $this->createMock(IUserSession::class);
+    }
+
+    public function dataTestProcessReminders(): array
+    {
+        return [
+            [
+                [], null
+            ],
+            [
+                [
+                    [
+                        'calendardata' => self::CALENDAR_DATA,
+						'displayname' => 'Personal',
+                        'type' => 'EMAIL',
+                        'uid' => 1,
+                        'id' => 1,
+                    ],
+                ],
+                $this->createMock(EmailProvider::class),
+            ],
+            [
+                [
+                    [
+                        'calendardata' => self::CALENDAR_DATA,
+						'displayname' => 'Personal',
+                        'type' => 'DISPLAY',
+                        'uid' => 1,
+                        'id' => 1,
+                    ],
+                ],
+                $this->createMock(PushProvider::class),
+            ]
+        ];
+    }
+
+	/**
+	 * @dataProvider dataTestProcessReminders
+	 * @param array $reminders
+	 * @param AbstractNotificationProvider|null $notificationProvider
+	 * @throws \OCA\DAV\CalDAV\Reminder\NotificationProvider\ProviderNotAvailableException
+	 * @throws \OCA\DAV\CalDAV\Reminder\NotificationTypeDoesNotExistException
+	 * @throws \OC\User\NoUserException
+	 */
+    public function testProcessReminders(array $reminders, ?AbstractNotificationProvider $notificationProvider): void
+    {
+        $user = $this->createMock(IUser::class);
+
+        $this->backend->expects($this->once())->method('getRemindersToProcess')->willReturn($reminders);
+        if (count($reminders) > 0) {
+            $this->userManager->expects($this->exactly(count($reminders)))->method('get')->willReturn($user);
+            $this->backend->expects($this->exactly(count($reminders)))->method('removeReminder');
+            $this->notificationProviderManager->expects($this->exactly(count($reminders)))->method('getProvider')->willReturn($notificationProvider);
+        }
+
+        $reminderService = new ReminderService($this->backend, $this->notificationProviderManager, $this->userManager, $this->groupManager, $this->userSession);
+        $reminderService->processReminders();
+    }
+
+	/**
+	 * @expectedException OC\User\NoUserException
+	 */
+    public function testProcessReminderWithBadUser(): void
+	{
+		$this->backend->expects($this->once())->method('getRemindersToProcess')->willReturn([
+			[
+				'calendardata' => self::CALENDAR_DATA,
+				'type' => 'DISPLAY',
+				'uid' => 1,
+				'id' => 1,
+			]
+		]);
+		$this->userManager->expects($this->once())->method('get')->with(1)->willReturn(null);
+		$reminderService = new ReminderService($this->backend, $this->notificationProviderManager, $this->userManager, $this->groupManager, $this->userSession);
+		$reminderService->processReminders();
+	}
+
+	public function providesTouchCalendarObject(): array
+	{
+		return [
+			[
+				'\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject',
+				[
+					'principaluri' => 'principals/users/personal'
+				],
+				[],
+				[
+					'calendarid' => 1,
+					'uri' => 'something.ics',
+				],
+				0
+			],
+			[
+				'\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject',
+				[
+					'principaluri' => 'principals/users/personal'
+				],
+				[],
+				[
+					'calendarid' => 1,
+					'uri' => 'something.ics',
+					'calendardata' => self::CALENDAR_DATA
+				],
+				0
+			],
+			[
+				'\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject',
+				[
+					'principaluri' => 'principals/users/someone',
+					'uri' => 'personal'
+				],
+				[
+					[
+						'{http://owncloud.org/ns}principal' => 'principals/users/someone'
+					]
+				],
+				[
+					'calendarid' => 1,
+					'uri' => 'something.ics',
+					'calendardata' => self::CALENDAR_DATA
+				],
+				0
+			],
+			[
+				'\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject',
+				[
+					'principaluri' => 'principals/users/someone',
+					'uri' => 'personal'
+				],
+				[
+					[
+						'{http://owncloud.org/ns}principal' => 'principals/groups/somegroup'
+					]
+				],
+				[
+					'calendarid' => 1,
+					'uri' => 'something.ics',
+					'calendardata' => self::CALENDAR_DATA
+				],
+				1
+			]
+		];
+	}
+
+	/**
+	 * @dataProvider providesTouchCalendarObject
+	 * @param string $action
+	 * @param array $calendarData
+	 * @param array $shares
+	 * @param array $objectData
+	 * @param int $numberOfGroups
+	 * @throws \OC\User\NoUserException
+	 * @throws \Sabre\VObject\InvalidDataException
+	 */
+	public function testOnTouchCalendarObject(string $action, array $calendarData, array $shares, array $objectData, int $numberOfGroups): void
+	{
+		$this->backend->expects($this->once())->method('cleanRemindersForEvent')->with($objectData['calendarid'], $objectData['uri']);
+
+		if ($action !== '\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject') {
+			$user = $this->createMock(IUser::class);
+			$user->expects($this->once())->method('getUID')->willReturn('user');
+
+			$this->userSession->expects($this->once())->method('getUser')->willReturn($user);
+			if ($numberOfGroups === 0) {
+				$this->backend->expects($this->exactly(count($shares) + 1))->method('insertReminder');
+			} else {
+				$group = $this->createMock(IGroup::class);
+				$groupUser = $this->createMock(IUser::class);
+				$groupUser->expects($this->once())->method('getUID')->willReturn('groupuser');
+				$group->expects($this->once())->method('getUsers')->willReturn([$groupUser]);
+				$this->groupManager->expects($this->exactly($numberOfGroups))->method('get')->willReturn($group);
+			}
+		}
+		$reminderService = new ReminderService($this->backend, $this->notificationProviderManager, $this->userManager, $this->groupManager, $this->userSession);
+		$reminderService->onTouchCalendarObject($action, $calendarData, $shares, $objectData);
+	}
+
+	/**
+	 * @expectedException OC\User\NoUserException
+	 */
+	public function testOnTouchCalendarObjectWithNoSession(): void
+	{
+		$this->backend->expects($this->once())->method('cleanRemindersForEvent');
+		$this->userSession->expects($this->once())->method('getUser')->willReturn(null);
+
+		$reminderService = new ReminderService($this->backend, $this->notificationProviderManager, $this->userManager, $this->groupManager, $this->userSession);
+		$reminderService->onTouchCalendarObject('', ['principaluri' => 'foo'], [], ['calendarid' => 1, 'uri' => 'bar']);
+	}
+
+	public function testOnTouchCalendarObjectWithNoCalendarURI(): void
+	{
+		$reminderService = new ReminderService($this->backend, $this->notificationProviderManager, $this->userManager, $this->groupManager, $this->userSession);
+		$this->assertNull($reminderService->onTouchCalendarObject('', [], [], []));
+	}
+}