Use recurrence instance to build iMip email

instead of the main VEVENT of a repeating event

Fixes part of https://github.com/nextcloud/calendar/issues/3919

Signed-off-by: Anna Larch <anna@nextcloud.com>

3 files changed, 875 insertions, 204 deletions

diff --git a/apps/dav/tests/unit/CalDAV/EventComparisonServiceTest.php b/apps/dav/tests/unit/CalDAV/EventComparisonServiceTest.php
new file mode 100644
index 00000000000..c21be3065c5
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/EventComparisonServiceTest.php
@@ -0,0 +1,146 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2023 Daniel Kesselberg <mail@danielkesselberg.de>
+ *
+ * @author 2023 Daniel Kesselberg <mail@danielkesselberg.de>
+ *
+ * @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\CalDAV;
+
+use OCA\DAV\CalDAV\EventComparisonService;
+use Sabre\VObject\Component\VCalendar;
+use Sabre\VObject\Component\VEvent;
+use Test\TestCase;
+
+class EventComparisonServiceTest extends TestCase
+{
+	/** @var EventComparisonService */
+	private $eventComparisonService;
+
+	protected function setUp(): void
+	{
+		$this->eventComparisonService = new EventComparisonService();
+	}
+
+	public function testNoModifiedEvent(): void
+	{
+		$vCalendarOld = new VCalendar();
+		$vCalendarNew = new VCalendar();
+
+		$vEventOld = $vCalendarOld->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RRULE' => 'FREQ=DAILY;INTERVAL=1;UNTIL=20160201T000000Z',
+		]);
+		$vEventOld->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$vEventOld->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$vEventNew = $vCalendarNew->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RRULE' => 'FREQ=DAILY;INTERVAL=1;UNTIL=20160201T000000Z',
+		]);
+		$vEventNew->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$vEventNew->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$result = $this->eventComparisonService->findModified($vCalendarNew, $vCalendarOld);
+		$this->assertEmpty($result['old']);
+		$this->assertEmpty($result['new']);
+	}
+
+	public function testNewEvent(): void
+	{
+		$vCalendarOld = null;
+		$vCalendarNew = new VCalendar();
+
+		$vEventNew = $vCalendarNew->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RRULE' => 'FREQ=DAILY;INTERVAL=1;UNTIL=20160201T000000Z',
+		]);
+		$vEventNew->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$vEventNew->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$result = $this->eventComparisonService->findModified($vCalendarNew, $vCalendarOld);
+		$this->assertNull($result['old']);
+		$this->assertEquals([$vEventNew], $result['new']);
+	}
+
+	public function testModifiedUnmodifiedEvent(): void
+	{
+		$vCalendarOld = new VCalendar();
+		$vCalendarNew = new VCalendar();
+
+		$vEventOld1 = $vCalendarOld->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+		]);
+		$vEventOld1->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$vEventOld1->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$vEventOld2 = $vCalendarOld->add('VEVENT', [
+			'UID' => 'uid-1235',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+		]);
+		$vEventOld2->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$vEventOld2->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$vEventNew1 = $vCalendarNew->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+		]);
+		$vEventNew1->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$vEventNew1->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$vEventNew2 = $vCalendarNew->add('VEVENT', [
+			'UID' => 'uid-1235',
+			'LAST-MODIFIED' => 123457,
+			'SEQUENCE' => 3,
+			'SUMMARY' => 'Fellowship meeting 2',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+		]);
+		$vEventNew2->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$vEventNew2->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$result = $this->eventComparisonService->findModified($vCalendarNew, $vCalendarOld);
+		$this->assertEquals([$vEventOld2], $result['old']);
+		$this->assertEquals([$vEventNew2], $result['new']);
+	}
+}
diff --git a/apps/dav/tests/unit/CalDAV/Schedule/IMipPluginTest.php b/apps/dav/tests/unit/CalDAV/Schedule/IMipPluginTest.php
index ecb602813cc..fdd707247ac 100644
--- a/apps/dav/tests/unit/CalDAV/Schedule/IMipPluginTest.php
+++ b/apps/dav/tests/unit/CalDAV/Schedule/IMipPluginTest.php
@@ -29,28 +29,27 @@
  */
 namespace OCA\DAV\Tests\unit\CalDAV\Schedule;
 
+use OCA\DAV\CalDAV\EventComparisonService;
 use OCA\DAV\CalDAV\Schedule\IMipPlugin;
+use OCA\DAV\CalDAV\Schedule\IMipService;
 use OCP\AppFramework\Utility\ITimeFactory;
-use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\Defaults;
 use OCP\IConfig;
-use OCP\IDBConnection;
-use OCP\IL10N;
-use OCP\IURLGenerator;
 use OCP\IUserManager;
-use OCP\L10N\IFactory;
 use OCP\Mail\IAttachment;
 use OCP\Mail\IEMailTemplate;
 use OCP\Mail\IMailer;
 use OCP\Mail\IMessage;
-use OCP\Security\ISecureRandom;
 use PHPUnit\Framework\MockObject\MockObject;
 use Psr\Log\LoggerInterface;
 use Sabre\VObject\Component\VCalendar;
+use Sabre\VObject\Component\VEvent;
 use Sabre\VObject\ITip\Message;
 use Test\TestCase;
+use function array_merge;
 
 class IMipPluginTest extends TestCase {
+
 	/** @var IMessage|MockObject */
 	private $mailMessage;
 
@@ -72,19 +71,28 @@ class IMipPluginTest extends TestCase {
 	/** @var IUserManager|MockObject */
 	private $userManager;
 
-	/** @var IQueryBuilder|MockObject */
-	private $queryBuilder;
-
 	/** @var IMipPlugin */
 	private $plugin;
 
+	/** @var IMipService|MockObject */
+	private $service;
+
+	/** @var Defaults|MockObject */
+	private $defaults;
+
+	/** @var LoggerInterface|MockObject */
+	private $logger;
+
+	/** @var EventComparisonService|MockObject */
+	private $eventComparisonService;
+
 	protected function setUp(): void {
 		$this->mailMessage = $this->createMock(IMessage::class);
 		$this->mailMessage->method('setFrom')->willReturn($this->mailMessage);
 		$this->mailMessage->method('setReplyTo')->willReturn($this->mailMessage);
 		$this->mailMessage->method('setTo')->willReturn($this->mailMessage);
 
-		$this->mailer = $this->getMockBuilder(IMailer::class)->disableOriginalConstructor()->getMock();
+		$this->mailer = $this->createMock(IMailer::class);
 		$this->mailer->method('createMessage')->willReturn($this->mailMessage);
 
 		$this->emailTemplate = $this->createMock(IEMailTemplate::class);
@@ -93,249 +101,482 @@ class IMipPluginTest extends TestCase {
 		$this->emailAttachment = $this->createMock(IAttachment::class);
 		$this->mailer->method('createAttachment')->willReturn($this->emailAttachment);
 
-		/** @var LoggerInterface|MockObject $logger */
-		$logger = $this->getMockBuilder(LoggerInterface::class)->disableOriginalConstructor()->getMock();
+		$this->logger = $this->createMock(LoggerInterface::class);
 
-		$this->timeFactory = $this->getMockBuilder(ITimeFactory::class)->disableOriginalConstructor()->getMock();
+		$this->timeFactory = $this->createMock(ITimeFactory::class);
 		$this->timeFactory->method('getTime')->willReturn(1496912528); // 2017-01-01
 
 		$this->config = $this->createMock(IConfig::class);
 
 		$this->userManager = $this->createMock(IUserManager::class);
 
-		$l10n = $this->createMock(IL10N::class);
-		$l10n->method('t')
-			->willReturnCallback(function ($text, $parameters = []) {
-				return vsprintf($text, $parameters);
-			});
-		$l10nFactory = $this->createMock(IFactory::class);
-		$l10nFactory->method('get')->willReturn($l10n);
-
-		$urlGenerator = $this->createMock(IURLGenerator::class);
-
-		$this->queryBuilder = $this->createMock(IQueryBuilder::class);
-		$db = $this->createMock(IDBConnection::class);
-		$db->method('getQueryBuilder')
-			->with()
-			->willReturn($this->queryBuilder);
-
-		$random = $this->createMock(ISecureRandom::class);
-		$random->method('generate')
-			->with(60, 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789')
-			->willReturn('random_token');
-
-		$defaults = $this->createMock(Defaults::class);
-		$defaults->method('getName')
+		$this->defaults = $this->createMock(Defaults::class);
+		$this->defaults->method('getName')
 			->willReturn('Instance Name 123');
 
-		$this->plugin = new IMipPlugin($this->config, $this->mailer, $logger, $this->timeFactory, $l10nFactory, $urlGenerator, $defaults, $random, $db, $this->userManager, 'user123');
+		$this->service = $this->createMock(IMipService::class);
+
+		$this->eventComparisonService = $this->createMock(EventComparisonService::class);
+
+		$this->plugin = new IMipPlugin(
+			$this->config,
+			$this->mailer,
+			$this->logger,
+			$this->timeFactory,
+			$this->defaults,
+			$this->userManager,
+			'user123',
+			$this->service,
+			$this->eventComparisonService
+		);
 	}
 
-	public function testDelivery(): void {
-		$this->config
-			->expects($this->any())
-			->method('getAppValue')
-			->willReturnMap([
-				['dav', 'invitation_link_recipients', 'yes', 'yes'],
-			]);
-		$this->mailer->method('validateMailAddress')->willReturn(true);
-
-		$message = $this->_testMessage();
-		$this->_expectSend();
+	public function testDeliveryNoSignificantChange(): void {
+		$message = new Message();
+		$message->method = 'REQUEST';
+		$message->message = new VCalendar();
+		$message->message->add('VEVENT', array_merge([
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 0,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		], []));
+		$message->message->VEVENT->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$message->message->VEVENT->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE']);
+		$message->sender = 'mailto:gandalf@wiz.ard';
+		$message->senderName = 'Mr. Wizard';
+		$message->recipient = 'mailto:' . 'frodo@hobb.it';
+		$message->significantChange = false;
 		$this->plugin->schedule($message);
-		$this->assertEquals('1.1', $message->getScheduleStatus());
+		$this->assertEquals('1.0', $message->getScheduleStatus());
 	}
 
-	public function testFailedDelivery(): void {
-		$this->config
-			->expects($this->any())
+	public function testParsingSingle(): void {
+		$message = new Message();
+		$message->method = 'REQUEST';
+		$newVCalendar = new VCalendar();
+		$newVevent = new VEvent($newVCalendar, 'one', array_merge([
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 1,
+			'SUMMARY' => 'Fellowship meeting without (!) Boromir',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		], []));
+		$newVevent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$newVevent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE',  'CN' => 'Frodo']);
+		$message->message = $newVCalendar;
+		$message->sender = 'mailto:gandalf@wiz.ard';
+		$message->senderName = 'Mr. Wizard';
+		$message->recipient = 'mailto:' . 'frodo@hobb.it';
+		// save the old copy in the plugin
+		$oldVCalendar = new VCalendar();
+		$oldVEvent = new VEvent($oldVCalendar, 'one', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 0,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		]);
+		$oldVEvent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$oldVEvent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+		$oldVEvent->add('ATTENDEE', 'mailto:' . 'boromir@tra.it.or', ['RSVP' => 'TRUE']);
+		$oldVCalendar->add($oldVEvent);
+		$data = ['invitee_name' => 'Mr. Wizard',
+			'meeting_title' => 'Fellowship meeting without (!) Boromir',
+			'attendee_name' => 'frodo@hobb.it'
+		];
+		$this->plugin->setVCalendar($oldVCalendar);
+		$this->service->expects(self::once())
+			->method('getLastOccurrence')
+			->willReturn('1496912700');
+		$this->mailer->expects(self::once())
+			->method('validateMailAddress')
+			->with('frodo@hobb.it')
+			->willReturn(true);
+		$this->eventComparisonService->expects(self::once())
+			->method('findModified')
+			->willReturn(['new' => [$newVevent], 'old' => [$oldVEvent]]);
+		$this->service->expects(self::once())
+			->method('buildBodyData')
+			->with($newVevent, $oldVEvent)
+			->willReturn($data);
+		$this->userManager->expects(self::never())
+			->method('getDisplayName');
+		$this->service->expects(self::once())
+			->method('getFrom');
+		$this->service->expects(self::once())
+			->method('addSubjectAndHeading')
+			->with($this->emailTemplate, 'request', 'Mr. Wizard', 'Fellowship meeting without (!) Boromir');
+		$this->service->expects(self::once())
+			->method('addBulletList')
+			->with($this->emailTemplate, $newVevent, $data);
+		$this->service->expects(self::once())
+			->method('getAttendeeRsvpOrReqForParticipant')
+			->willReturn(true);
+		$this->config->expects(self::once())
 			->method('getAppValue')
-			->willReturnMap([
-				['dav', 'invitation_link_recipients', 'yes', 'yes'],
-			]);
-		$this->mailer->method('validateMailAddress')->willReturn(true);
-
-		$message = $this->_testMessage();
-		$this->mailer
+			->with('dav', 'invitation_link_recipients', 'yes')
+			->willReturn('yes');
+		$this->service->expects(self::once())
+			->method('createInvitationToken')
+			->with($message,$newVevent, '1496912700')
+			->willReturn('token');
+		$this->service->expects(self::once())
+			->method('addResponseButtons')
+			->with($this->emailTemplate, 'token');
+		$this->service->expects(self::once())
+			->method('addMoreOptionsButton')
+			->with($this->emailTemplate, 'token');
+		$this->mailer->expects(self::once())
 			->method('send')
-			->willThrowException(new \Exception());
-		$this->_expectSend();
-		$this->plugin->schedule($message);
-		$this->assertEquals('5.0', $message->getScheduleStatus());
-	}
-
-	public function testInvalidEmailDelivery(): void {
-		$this->mailer->method('validateMailAddress')->willReturn(false);
-
-		$message = $this->_testMessage();
+			->willReturn([]);
 		$this->plugin->schedule($message);
-		$this->assertEquals('5.0', $message->getScheduleStatus());
+		$this->assertEquals('1.1', $message->getScheduleStatus());
 	}
 
-	public function testDeliveryWithNoCommonName(): void {
-		$this->config
-			->expects($this->any())
-			->method('getAppValue')
-			->willReturnMap([
-				['dav', 'invitation_link_recipients', 'yes', 'yes'],
-			]);
-		$this->mailer->method('validateMailAddress')->willReturn(true);
-
-		$message = $this->_testMessage();
-		$message->senderName = null;
-
-		$this->userManager->expects($this->once())
+	public function testParsingRecurrence(): void {
+		$message = new Message();
+		$message->method = 'REQUEST';
+		$newVCalendar = new VCalendar();
+		$newVevent = new VEvent($newVCalendar, 'one', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RRULE' => 'FREQ=DAILY;INTERVAL=1;UNTIL=20160201T000000Z'
+		]);
+		$newVevent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$newVevent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE',  'CN' => 'Frodo']);
+		$newvEvent2 = new VEvent($newVCalendar, 'two', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 1,
+			'SUMMARY' => 'Elevenses',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RECURRENCE-ID' => new \DateTime('2016-01-01 00:00:00')
+		]);
+		$newvEvent2->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$newvEvent2->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+		$message->message = $newVCalendar;
+		$message->sender = 'mailto:gandalf@wiz.ard';
+		$message->recipient = 'mailto:' . 'frodo@hobb.it';
+		// save the old copy in the plugin
+		$oldVCalendar = new VCalendar();
+		$oldVEvent = new VEvent($oldVCalendar, 'one', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RRULE' => 'FREQ=DAILY;INTERVAL=1;UNTIL=20160201T000000Z'
+		]);
+		$oldVEvent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$oldVEvent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+		$data = ['invitee_name' => 'Mr. Wizard',
+			'meeting_title' => 'Elevenses',
+			'attendee_name' => 'frodo@hobb.it'
+		];
+		$this->plugin->setVCalendar($oldVCalendar);
+		$this->service->expects(self::once())
+			->method('getLastOccurrence')
+			->willReturn('1496912700');
+		$this->mailer->expects(self::once())
+			->method('validateMailAddress')
+			->with('frodo@hobb.it')
+			->willReturn(true);
+		$this->eventComparisonService->expects(self::once())
+			->method('findModified')
+			->willReturn(['old' => [] ,'new' => [$newVevent]]);
+		$this->service->expects(self::once())
+			->method('buildBodyData')
+			->with($newVevent, null)
+			->willReturn($data);
+		$this->userManager->expects(self::once())
 			->method('getDisplayName')
-			->with('user123')
 			->willReturn('Mr. Wizard');
-
-		$this->_expectSend();
+		$this->service->expects(self::once())
+			->method('getFrom');
+		$this->service->expects(self::once())
+			->method('addSubjectAndHeading')
+			->with($this->emailTemplate, 'request', 'Mr. Wizard', 'Elevenses');
+		$this->service->expects(self::once())
+			->method('addBulletList')
+			->with($this->emailTemplate, $newVevent, $data);
+		$this->service->expects(self::once())
+			->method('getAttendeeRsvpOrReqForParticipant')
+			->willReturn(true);
+		$this->config->expects(self::once())
+			->method('getAppValue')
+			->with('dav', 'invitation_link_recipients', 'yes')
+			->willReturn('yes');
+		$this->service->expects(self::once())
+			->method('createInvitationToken')
+			->with($message, $newVevent, '1496912700')
+			->willReturn('token');
+		$this->service->expects(self::once())
+			->method('addResponseButtons')
+			->with($this->emailTemplate, 'token');
+		$this->service->expects(self::once())
+			->method('addMoreOptionsButton')
+			->with($this->emailTemplate, 'token');
+		$this->mailer->expects(self::once())
+			->method('send')
+			->willReturn([]);
 		$this->plugin->schedule($message);
 		$this->assertEquals('1.1', $message->getScheduleStatus());
 	}
 
-	/**
-	 * @dataProvider dataNoMessageSendForPastEvents
-	 */
-	public function testNoMessageSendForPastEvents(array $veventParams, bool $expectsMail): void {
-		$this->config
-			->method('getAppValue')
-			->willReturn('yes');
-		$this->mailer->method('validateMailAddress')->willReturn(true);
-
-		$message = $this->_testMessage($veventParams);
+	public function testEmailValidationFailed() {
+		$message = new Message();
+		$message->method = 'REQUEST';
+		$message->message = new VCalendar();
+		$message->message->add('VEVENT', array_merge([
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 0,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		], []));
+		$message->message->VEVENT->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$message->message->VEVENT->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE']);
+		$message->sender = 'mailto:gandalf@wiz.ard';
+		$message->senderName = 'Mr. Wizard';
+		$message->recipient = 'mailto:' . 'frodo@hobb.it';
 
-		$this->_expectSend('frodo@hobb.it', $expectsMail, $expectsMail);
+		$this->service->expects(self::once())
+			->method('getLastOccurrence')
+			->willReturn('1496912700');
+		$this->mailer->expects(self::once())
+			->method('validateMailAddress')
+			->with('frodo@hobb.it')
+			->willReturn(false);
 
 		$this->plugin->schedule($message);
-
-		if ($expectsMail) {
-			$this->assertEquals('1.1', $message->getScheduleStatus());
-		} else {
-			$this->assertEquals(false, $message->getScheduleStatus());
-		}
+		$this->assertEquals('5.0', $message->getScheduleStatus());
 	}
 
-	public function dataNoMessageSendForPastEvents() {
-		return [
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00')], false],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DTEND' => new \DateTime('2017-01-01 00:00:00')], false],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DTEND' => new \DateTime('2017-12-31 00:00:00')], true],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DURATION' => 'P1D'], false],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DURATION' => 'P52W'], true],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DTEND' => new \DateTime('2017-01-01 00:00:00'), 'RRULE' => 'FREQ=WEEKLY'], true],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DTEND' => new \DateTime('2017-01-01 00:00:00'), 'RRULE' => 'FREQ=WEEKLY;COUNT=3'], false],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DTEND' => new \DateTime('2017-01-01 00:00:00'), 'RRULE' => 'FREQ=WEEKLY;UNTIL=20170301T000000Z'], false],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DTEND' => new \DateTime('2017-01-01 00:00:00'), 'RRULE' => 'FREQ=WEEKLY;COUNT=33'], true],
-			[['DTSTART' => new \DateTime('2017-01-01 00:00:00'), 'DTEND' => new \DateTime('2017-01-01 00:00:00'), 'RRULE' => 'FREQ=WEEKLY;UNTIL=20171001T000000Z'], true],
+	public function testFailedDelivery(): void {
+		$message = new Message();
+		$message->method = 'REQUEST';
+		$newVcalendar = new VCalendar();
+		$newVevent = new VEvent($newVcalendar, 'one', array_merge([
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 1,
+			'SUMMARY' => 'Fellowship meeting without (!) Boromir',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		], []));
+		$newVevent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$newVevent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE',  'CN' => 'Frodo']);
+		$message->message = $newVcalendar;
+		$message->sender = 'mailto:gandalf@wiz.ard';
+		$message->senderName = 'Mr. Wizard';
+		$message->recipient = 'mailto:' . 'frodo@hobb.it';
+		// save the old copy in the plugin
+		$oldVcalendar = new VCalendar();
+		$oldVevent = new VEvent($oldVcalendar, 'one', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 0,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		]);
+		$oldVevent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$oldVevent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+		$oldVevent->add('ATTENDEE', 'mailto:' . 'boromir@tra.it.or', ['RSVP' => 'TRUE']);
+		$oldVcalendar->add($oldVevent);
+		$data = ['invitee_name' => 'Mr. Wizard',
+			'meeting_title' => 'Fellowship meeting without (!) Boromir',
+			'attendee_name' => 'frodo@hobb.it'
 		];
-	}
-
-	/**
-	 * @dataProvider dataIncludeResponseButtons
-	 */
-	public function testIncludeResponseButtons(string $config_setting, string $recipient, bool $has_buttons): void {
-		$message = $this->_testMessage([], $recipient);
-		$this->mailer->method('validateMailAddress')->willReturn(true);
-
-		$this->_expectSend($recipient, true, $has_buttons);
-		$this->config
-			->expects($this->any())
+		$this->plugin->setVCalendar($oldVcalendar);
+		$this->service->expects(self::once())
+			->method('getLastOccurrence')
+			->willReturn('1496912700');
+		$this->mailer->expects(self::once())
+			->method('validateMailAddress')
+			->with('frodo@hobb.it')
+			->willReturn(true);
+		$this->eventComparisonService->expects(self::once())
+			->method('findModified')
+			->willReturn(['old' => [] ,'new' => [$newVevent]]);
+		$this->service->expects(self::once())
+			->method('buildBodyData')
+			->with($newVevent, null)
+			->willReturn($data);
+		$this->userManager->expects(self::never())
+			->method('getDisplayName');
+		$this->service->expects(self::once())
+			->method('getFrom');
+		$this->service->expects(self::once())
+			->method('addSubjectAndHeading')
+			->with($this->emailTemplate, 'request', 'Mr. Wizard', 'Fellowship meeting without (!) Boromir');
+		$this->service->expects(self::once())
+			->method('addBulletList')
+			->with($this->emailTemplate, $newVevent, $data);
+		$this->service->expects(self::once())
+			->method('getAttendeeRsvpOrReqForParticipant')
+			->willReturn(true);
+		$this->config->expects(self::once())
 			->method('getAppValue')
-			->willReturnMap([
-				['dav', 'invitation_link_recipients', 'yes', $config_setting],
-			]);
-
+			->with('dav', 'invitation_link_recipients', 'yes')
+			->willReturn('yes');
+		$this->service->expects(self::once())
+			->method('createInvitationToken')
+			->with($message, $newVevent, '1496912700')
+			->willReturn('token');
+		$this->service->expects(self::once())
+			->method('addResponseButtons')
+			->with($this->emailTemplate, 'token');
+		$this->service->expects(self::once())
+			->method('addMoreOptionsButton')
+			->with($this->emailTemplate, 'token');
+		$this->mailer->expects(self::once())
+			->method('send')
+			->willReturn([]);
+		$this->mailer
+			->method('send')
+			->willThrowException(new \Exception());
+		$this->logger->expects(self::once())
+			->method('error');
 		$this->plugin->schedule($message);
-		$this->assertEquals('1.1', $message->getScheduleStatus());
+		$this->assertEquals('5.0', $message->getScheduleStatus());
 	}
 
-	public function dataIncludeResponseButtons() {
-		return [
-			// dav.invitation_link_recipients, recipient, $has_buttons
-			[ 'yes', 'joe@internal.com', true],
-			[ 'joe@internal.com', 'joe@internal.com', true],
-			[ 'internal.com', 'joe@internal.com', true],
-			[ 'pete@otherinternal.com,internal.com', 'joe@internal.com', true],
-			[ 'no', 'joe@internal.com', false],
-			[ 'internal.com', 'joe@external.com', false],
-			[ 'jane@otherinternal.com,internal.com', 'joe@otherinternal.com', false],
+	public function testNoOldEvent(): void {
+		$message = new Message();
+		$message->method = 'REQUEST';
+		$newVCalendar = new VCalendar();
+		$newVevent = new VEvent($newVCalendar, 'VEVENT', array_merge([
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 1,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		], []));
+		$newVevent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$newVevent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+		$message->message = $newVCalendar;
+		$message->sender = 'mailto:gandalf@wiz.ard';
+		$message->senderName = 'Mr. Wizard';
+		$message->recipient = 'mailto:' . 'frodo@hobb.it';
+		$data = ['invitee_name' => 'Mr. Wizard',
+			'meeting_title' => 'Fellowship meeting',
+			'attendee_name' => 'frodo@hobb.it'
 		];
-	}
 
-	public function testMessageSendWhenEventWithoutName(): void {
-		$this->config
+		$this->service->expects(self::once())
+			->method('getLastOccurrence')
+			->willReturn('1496912700');
+		$this->mailer->expects(self::once())
+			->method('validateMailAddress')
+			->with('frodo@hobb.it')
+			->willReturn(true);
+		$this->eventComparisonService->expects(self::once())
+			->method('findModified')
+			->with($newVCalendar, null)
+			->willReturn(['old' => [] ,'new' => [$newVevent]]);
+		$this->service->expects(self::once())
+			->method('buildBodyData')
+			->with($newVevent, null)
+			->willReturn($data);
+		$this->userManager->expects(self::never())
+			->method('getDisplayName');
+		$this->service->expects(self::once())
+			->method('getFrom');
+		$this->service->expects(self::once())
+			->method('addSubjectAndHeading')
+			->with($this->emailTemplate, 'request', 'Mr. Wizard', 'Fellowship meeting');
+		$this->service->expects(self::once())
+			->method('addBulletList')
+			->with($this->emailTemplate, $newVevent, $data);
+		$this->service->expects(self::once())
+			->method('getAttendeeRsvpOrReqForParticipant')
+			->willReturn(true);
+		$this->config->expects(self::once())
 			->method('getAppValue')
+			->with('dav', 'invitation_link_recipients', 'yes')
 			->willReturn('yes');
-		$this->mailer->method('validateMailAddress')->willReturn(true);
-
-		$message = $this->_testMessage(['SUMMARY' => '']);
-		$this->_expectSend('frodo@hobb.it', true, true, 'Invitation: Untitled event');
-		$this->emailTemplate->expects($this->once())
-			->method('addHeading')
-			->with('Invitation');
+		$this->service->expects(self::once())
+			->method('createInvitationToken')
+			->with($message, $newVevent, '1496912700')
+			->willReturn('token');
+		$this->service->expects(self::once())
+			->method('addResponseButtons')
+			->with($this->emailTemplate, 'token');
+		$this->service->expects(self::once())
+			->method('addMoreOptionsButton')
+			->with($this->emailTemplate, 'token');
+		$this->mailer->expects(self::once())
+			->method('send')
+			->willReturn([]);
+		$this->mailer
+			->method('send')
+			->willReturn([]);
 		$this->plugin->schedule($message);
 		$this->assertEquals('1.1', $message->getScheduleStatus());
 	}
 
-	private function _testMessage(array $attrs = [], string $recipient = 'frodo@hobb.it') {
+	public function testNoButtons(): void {
 		$message = new Message();
 		$message->method = 'REQUEST';
-		$message->message = new VCalendar();
-		$message->message->add('VEVENT', array_merge([
+		$newVCalendar = new VCalendar();
+		$newVevent = new VEvent($newVCalendar, 'VEVENT', array_merge([
 			'UID' => 'uid-1234',
-			'SEQUENCE' => 0,
+			'SEQUENCE' => 1,
 			'SUMMARY' => 'Fellowship meeting',
-			'DTSTART' => new \DateTime('2018-01-01 00:00:00')
-		], $attrs));
-		$message->message->VEVENT->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
-		$message->message->VEVENT->add('ATTENDEE', 'mailto:'.$recipient, [ 'RSVP' => 'TRUE' ]);
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00')
+		], []));
+		$newVevent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$newVevent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+		$message->message = $newVCalendar;
 		$message->sender = 'mailto:gandalf@wiz.ard';
-		$message->senderName = 'Mr. Wizard';
-		$message->recipient = 'mailto:'.$recipient;
-		return $message;
-	}
-
+		$message->recipient = 'mailto:' . 'frodo@hobb.it';
+		$data = ['invitee_name' => 'Mr. Wizard',
+			'meeting_title' => 'Fellowship meeting',
+			'attendee_name' => 'frodo@hobb.it'
+		];
 
-	private function _expectSend(string $recipient = 'frodo@hobb.it', bool $expectSend = true, bool $expectButtons = true, string $subject = 'Invitation: Fellowship meeting'): void {
-		// if the event is in the past, we skip out
-		if (!$expectSend) {
-			$this->mailer
-				->expects($this->never())
-				->method('send');
-			return;
-		}
-
-		$this->emailTemplate->expects($this->once())
-			->method('setSubject')
-			->with($subject);
-		$this->mailMessage->expects($this->once())
-			->method('setTo')
-			->with([$recipient => null]);
-		$this->mailMessage->expects($this->once())
-			->method('setReplyTo')
-			->with(['gandalf@wiz.ard' => 'Mr. Wizard']);
-		$this->mailMessage->expects($this->once())
-			->method('setFrom')
-			->with(['invitations-noreply@localhost' => 'Mr. Wizard via Instance Name 123']);
+		$this->service->expects(self::once())
+			->method('getLastOccurrence')
+			->willReturn('1496912700');
+		$this->mailer->expects(self::once())
+			->method('validateMailAddress')
+			->with('frodo@hobb.it')
+			->willReturn(true);
+		$this->eventComparisonService->expects(self::once())
+			->method('findModified')
+			->with($newVCalendar, null)
+			->willReturn(['old' => [] ,'new' => [$newVevent]]);
+		$this->service->expects(self::once())
+			->method('buildBodyData')
+			->with($newVevent, null)
+			->willReturn($data);
+		$this->userManager->expects(self::once())
+			->method('getDisplayName')
+			->willReturn('Mr. Wizard');
+		$this->service->expects(self::once())
+			->method('getFrom');
+		$this->service->expects(self::once())
+			->method('addSubjectAndHeading')
+			->with($this->emailTemplate, 'request', 'Mr. Wizard', 'Fellowship meeting');
+		$this->service->expects(self::once())
+			->method('addBulletList')
+			->with($this->emailTemplate, $newVevent, $data);
+		$this->service->expects(self::once())
+			->method('getAttendeeRsvpOrReqForParticipant')
+			->willReturn(true);
+		$this->config->expects(self::once())
+			->method('getAppValue')
+			->with('dav', 'invitation_link_recipients', 'yes')
+			->willReturn('no');
+		$this->service->expects(self::never())
+			->method('createInvitationToken');
+		$this->service->expects(self::never())
+			->method('addResponseButtons');
+		$this->service->expects(self::never())
+			->method('addMoreOptionsButton');
+		$this->mailer->expects(self::once())
+			->method('send')
+			->willReturn([]);
 		$this->mailer
-			->expects($this->once())
-			->method('send');
-
-		if ($expectButtons) {
-			$this->queryBuilder->expects($this->once())
-				->method('insert')
-				->with('calendar_invitations')
-				->willReturn($this->queryBuilder);
-			$this->queryBuilder->expects($this->once())
-				->method('values')
-				->willReturn($this->queryBuilder);
-			$this->queryBuilder->expects($this->once())
-				->method('execute');
-		} else {
-			$this->queryBuilder->expects($this->never())
-				->method('insert')
-				->with('calendar_invitations');
-		}
+			->method('send')
+			->willReturn([]);
+		$this->plugin->schedule($message);
+		$this->assertEquals('1.1', $message->getScheduleStatus());
 	}
 }
diff --git a/apps/dav/tests/unit/CalDAV/Schedule/IMipServiceTest.php b/apps/dav/tests/unit/CalDAV/Schedule/IMipServiceTest.php
new file mode 100644
index 00000000000..000476050c7
--- /dev/null
+++ b/apps/dav/tests/unit/CalDAV/Schedule/IMipServiceTest.php
@@ -0,0 +1,284 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @copyright Copyright (c) 2017, Georg Ehrke
+ *
+ * @author brad2014 <brad2014@users.noreply.github.com>
+ * @author Brad Rubenstein <brad@wbr.tech>
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ * @author Georg Ehrke <oc.list@georgehrke.com>
+ * @author Joas Schilling <coding@schilljs.com>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Thomas Citharel <nextcloud@tcit.fr>
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ *
+ * @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\Schedule;
+
+use OC\L10N\L10N;
+use OC\L10N\LazyL10N;
+use OC\URLGenerator;
+use OCA\DAV\CalDAV\Schedule\IMipService;
+use OCP\IConfig;
+use OCP\IDBConnection;
+use OCP\L10N\IFactory as L10NFactory;
+use OCP\Security\ISecureRandom;
+use PHPUnit\Framework\MockObject\MockObject;
+use Sabre\VObject\Component\VCalendar;
+use Sabre\VObject\Component\VEvent;
+use Sabre\VObject\Property\ICalendar\DateTime;
+use Test\TestCase;
+
+class IMipServiceTest extends TestCase
+{
+	/** @var URLGenerator|MockObject */
+	private $urlGenerator;
+
+	/** @var IConfig|MockObject */
+	private $config;
+
+	/** @var IDBConnection|MockObject */
+	private $db;
+
+	/** @var ISecureRandom|MockObject */
+	private $random;
+
+	/** @var L10NFactory|MockObject */
+	private $l10nFactory;
+
+	/** @var L10N|MockObject */
+	private $l10n;
+
+	/** @var IMipService */
+	private $service;
+
+	protected function setUp(): void
+	{
+		$this->urlGenerator = $this->createMock(URLGenerator::class);
+		$this->config = $this->createMock(IConfig::class);
+		$this->db = $this->createMock(IDBConnection::class);
+		$this->random = $this->createMock(ISecureRandom::class);
+		$this->l10nFactory = $this->createMock(L10NFactory::class);
+		$this->l10n = $this->createMock(LazyL10N::class);
+		$this->l10nFactory->expects(self::once())
+			->method('findGenericLanguage')
+			->willReturn('en');
+		$this->l10nFactory->expects(self::once())
+			->method('get')
+			->with('dav', 'en')
+			->willReturn($this->l10n);
+		$this->service = new IMipService(
+			$this->urlGenerator,
+			$this->config,
+			$this->db,
+			$this->random,
+			$this->l10nFactory
+		);
+	}
+
+	public function testGetFrom(): void
+	{
+		$senderName = "Detective McQueen";
+		$default = "Twin Lakes Police Department - Darkside Division";
+		$expected = "Detective McQueen via Twin Lakes Police Department - Darkside Division";
+
+		$this->l10n->expects(self::once())
+			->method('t')
+			->willReturn($expected);
+
+		$actual = $this->service->getFrom($senderName, $default);
+		$this->assertEquals($expected, $actual);
+	}
+
+	public function testBuildBodyDataCreated(): void
+	{
+		$vCalendar = new VCalendar();
+		$oldVevent = null;
+		$newVevent = new VEvent($vCalendar, 'two', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 3,
+			'LAST-MODIFIED' => 789456,
+			'SUMMARY' => 'Second Breakfast',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RECURRENCE-ID' => new \DateTime('2016-01-01 00:00:00')
+		]);
+
+		$expected = [
+			'meeting_when' => $this->service->generateWhenString($newVevent),
+			'meeting_description' => '',
+			'meeting_title' => 'Second Breakfast',
+			'meeting_location' => '',
+			'meeting_url' => '',
+			'meeting_url_html' => '',
+		];
+
+		$actual = $this->service->buildBodyData($newVevent, $oldVevent);
+
+		$this->assertEquals($expected, $actual);
+	}
+
+	public function testBuildBodyDataUpdate(): void
+	{
+		$vCalendar = new VCalendar();
+		$oldVevent = new VEvent($vCalendar, 'two', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 1,
+			'LAST-MODIFIED' => 456789,
+			'SUMMARY' => 'Elevenses',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RECURRENCE-ID' => new \DateTime('2016-01-01 00:00:00')
+		]);
+		$oldVevent->add('ORGANIZER', 'mailto:gandalf@wiz.ard');
+		$oldVevent->add('ATTENDEE', 'mailto:' . 'frodo@hobb.it', ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+		$newVevent = new VEvent($vCalendar, 'two', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 3,
+			'LAST-MODIFIED' => 789456,
+			'SUMMARY' => 'Second Breakfast',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RECURRENCE-ID' => new \DateTime('2016-01-01 00:00:00')
+		]);
+
+		$expected = [
+			'meeting_when' => $this->service->generateWhenString($newVevent),
+			'meeting_description' => '',
+			'meeting_title' => 'Second Breakfast',
+			'meeting_location' => '',
+			'meeting_url' => '',
+			'meeting_url_html' => '',
+			'meeting_when_html' => $this->service->generateWhenString($newVevent),
+			'meeting_title_html' => sprintf("<span style='text-decoration: line-through'>%s</span><br />%s", 'Elevenses', 'Second Breakfast'),
+			'meeting_description_html' => '',
+			'meeting_location_html' => ''
+		];
+
+		$actual = $this->service->buildBodyData($newVevent, $oldVevent);
+
+		$this->assertEquals($expected, $actual);
+	}
+
+	public function testGenerateWhenStringHourlyEvent(): void {
+		$vCalendar = new VCalendar();
+		$vevent = new VEvent($vCalendar, 'two', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 1,
+			'LAST-MODIFIED' => 456789,
+			'SUMMARY' => 'Elevenses',
+			'TZID' => 'Europe/Vienna',
+			'DTSTART' => (new \DateTime('2016-01-01 08:00:00'))->setTimezone(new \DateTimeZone('Europe/Vienna')),
+			'DTEND' => (new \DateTime('2016-01-01 09:00:00'))->setTimezone(new \DateTimeZone('Europe/Vienna')),
+		]);
+
+		$this->l10n->expects(self::exactly(3))
+			->method('l')
+			->withConsecutive(
+				['weekdayName', (new \DateTime('2016-01-01 08:00:00'))->setTimezone(new \DateTimeZone('Europe/Vienna')), ['width' => 'abbreviated']],
+				['datetime', (new \DateTime('2016-01-01 08:00:00'))->setTimezone(new \DateTimeZone('Europe/Vienna')), ['width' => 'medium|short']],
+				['time', (new \DateTime('2016-01-01 09:00:00'))->setTimezone(new \DateTimeZone('Europe/Vienna')), ['width' => 'short']]
+			)->willReturnOnConsecutiveCalls(
+				'Fr.',
+				'01.01. 08:00',
+				'09:00'
+			);
+
+		$expected = 'Fr., 01.01. 08:00 - 09:00 (Europe/Vienna)';
+		$actual = $this->service->generateWhenString($vevent);
+		$this->assertEquals($expected, $actual);
+	}
+
+	public function testGetLastOccurrenceRRULE(): void
+	{
+		$vCalendar = new VCalendar();
+		$vCalendar->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'RRULE' => 'FREQ=DAILY;INTERVAL=1;UNTIL=20160201T000000Z',
+		]);
+
+		$occurrence = $this->service->getLastOccurrence($vCalendar);
+		$this->assertEquals(1454284800, $occurrence);
+	}
+
+	public function testGetLastOccurrenceEndDate(): void
+	{
+		$vCalendar = new VCalendar();
+		$vCalendar->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'DTEND' => new \DateTime('2017-01-01 00:00:00'),
+		]);
+
+		$occurrence = $this->service->getLastOccurrence($vCalendar);
+		$this->assertEquals(1483228800, $occurrence);
+	}
+
+	public function testGetLastOccurrenceDuration(): void
+	{
+		$vCalendar = new VCalendar();
+		$vCalendar->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+			'DURATION' => 'P12W',
+		]);
+
+		$occurrence = $this->service->getLastOccurrence($vCalendar);
+		$this->assertEquals(1458864000, $occurrence);
+	}
+
+	public function testGetLastOccurrenceAllDay(): void
+	{
+		$vCalendar = new VCalendar();
+		$vEvent = $vCalendar->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+		]);
+
+		// rewrite from DateTime to Date
+		$vEvent->DTSTART['VALUE'] = 'DATE';
+
+		$occurrence = $this->service->getLastOccurrence($vCalendar);
+		$this->assertEquals(1451692800, $occurrence);
+	}
+
+	public function testGetLastOccurrenceFallback(): void
+	{
+		$vCalendar = new VCalendar();
+		$vCalendar->add('VEVENT', [
+			'UID' => 'uid-1234',
+			'LAST-MODIFIED' => 123456,
+			'SEQUENCE' => 2,
+			'SUMMARY' => 'Fellowship meeting',
+			'DTSTART' => new \DateTime('2016-01-01 00:00:00'),
+		]);
+
+		$occurrence = $this->service->getLastOccurrence($vCalendar);
+		$this->assertEquals(1451606400, $occurrence);
+	}
+}