1 files changed, 186 insertions, 0 deletions
diff --git a/apps/dav/lib/CalDAV/Status/StatusService.php b/apps/dav/lib/CalDAV/Status/StatusService.php
new file mode 100644
index 00000000000..9ee0e9bf356
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Status/StatusService.php
@@ -0,0 +1,186 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OCA\DAV\CalDAV\Status;
+
+use DateTimeImmutable;
+use OC\Calendar\CalendarQuery;
+use OCA\DAV\CalDAV\CalendarImpl;
+use OCA\UserStatus\Service\StatusService as UserStatusService;
+use OCP\AppFramework\Db\DoesNotExistException;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\Calendar\IManager;
+use OCP\DB\Exception;
+use OCP\ICache;
+use OCP\ICacheFactory;
+use OCP\IUser as User;
+use OCP\IUserManager;
+use OCP\User\IAvailabilityCoordinator;
+use OCP\UserStatus\IUserStatus;
+use Psr\Log\LoggerInterface;
+use Sabre\CalDAV\Xml\Property\ScheduleCalendarTransp;
+
+class StatusService {
+	private ICache $cache;
+	public function __construct(
+		private ITimeFactory $timeFactory,
+		private IManager $calendarManager,
+		private IUserManager $userManager,
+		private UserStatusService $userStatusService,
+		private IAvailabilityCoordinator $availabilityCoordinator,
+		private ICacheFactory $cacheFactory,
+		private LoggerInterface $logger,
+	) {
+		$this->cache = $cacheFactory->createLocal('CalendarStatusService');
+	}
+
+	public function processCalendarStatus(string $userId): void {
+		$user = $this->userManager->get($userId);
+		if ($user === null) {
+			return;
+		}
+
+		$availability = $this->availabilityCoordinator->getCurrentOutOfOfficeData($user);
+		if ($availability !== null && $this->availabilityCoordinator->isInEffect($availability)) {
+			$this->logger->debug('An Absence is in effect, skipping calendar status check', ['user' => $userId]);
+			return;
+		}
+
+		$calendarEvents = $this->cache->get($userId);
+		if ($calendarEvents === null) {
+			$calendarEvents = $this->getCalendarEvents($user);
+			$this->cache->set($userId, $calendarEvents, 300);
+		}
+
+		if (empty($calendarEvents)) {
+			try {
+				$this->userStatusService->revertUserStatus($userId, IUserStatus::MESSAGE_CALENDAR_BUSY);
+			} catch (Exception $e) {
+				if ($e->getReason() === Exception::REASON_UNIQUE_CONSTRAINT_VIOLATION) {
+					// A different process might have written another status
+					// update to the DB while we're processing our stuff.
+					// We cannot safely restore the status as we don't know which one is valid at this point
+					// So let's silently log this one and exit
+					$this->logger->debug('Unique constraint violation for live user status', ['exception' => $e]);
+					return;
+				}
+			}
+			$this->logger->debug('No calendar events found for status check', ['user' => $userId]);
+			return;
+		}
+
+		try {
+			$currentStatus = $this->userStatusService->findByUserId($userId);
+			// Was the status set by anything other than the calendar automation?
+			$userStatusTimestamp = $currentStatus->getIsUserDefined() && $currentStatus->getMessageId() !== IUserStatus::MESSAGE_CALENDAR_BUSY ? $currentStatus->getStatusTimestamp() : null;
+		} catch (DoesNotExistException) {
+			$userStatusTimestamp = null;
+			$currentStatus = null;
+		}
+
+		if (($currentStatus !== null && $currentStatus->getMessageId() === IUserStatus::MESSAGE_CALL)
+			|| ($currentStatus !== null && $currentStatus->getStatus() === IUserStatus::DND)
+			|| ($currentStatus !== null && $currentStatus->getStatus() === IUserStatus::INVISIBLE)) {
+			// We don't overwrite the call status, DND status or Invisible status
+			$this->logger->debug('Higher priority status detected, skipping calendar status change', ['user' => $userId]);
+			return;
+		}
+
+		// Filter events to see if we have any that apply to the calendar status
+		$applicableEvents = array_filter($calendarEvents, static function (array $calendarEvent) use ($userStatusTimestamp): bool {
+			if (empty($calendarEvent['objects'])) {
+				return false;
+			}
+			$component = $calendarEvent['objects'][0];
+			if (isset($component['X-NEXTCLOUD-OUT-OF-OFFICE'])) {
+				return false;
+			}
+			if (isset($component['DTSTART']) && $userStatusTimestamp !== null) {
+				/** @var DateTimeImmutable $dateTime */
+				$dateTime = $component['DTSTART'][0];
+				if ($dateTime instanceof DateTimeImmutable && $userStatusTimestamp > $dateTime->getTimestamp()) {
+					return false;
+				}
+			}
+			// Ignore events that are transparent
+			if (isset($component['TRANSP']) && strcasecmp($component['TRANSP'][0], 'TRANSPARENT') === 0) {
+				return false;
+			}
+			return true;
+		});
+
+		if (empty($applicableEvents)) {
+			try {
+				$this->userStatusService->revertUserStatus($userId, IUserStatus::MESSAGE_CALENDAR_BUSY);
+			} catch (Exception $e) {
+				if ($e->getReason() === Exception::REASON_UNIQUE_CONSTRAINT_VIOLATION) {
+					// A different process might have written another status
+					// update to the DB while we're processing our stuff.
+					// We cannot safely restore the status as we don't know which one is valid at this point
+					// So let's silently log this one and exit
+					$this->logger->debug('Unique constraint violation for live user status', ['exception' => $e]);
+					return;
+				}
+			}
+			$this->logger->debug('No status relevant events found, skipping calendar status change', ['user' => $userId]);
+			return;
+		}
+
+		// Only update the status if it's neccesary otherwise we mess up the timestamp
+		if ($currentStatus === null || $currentStatus->getMessageId() !== IUserStatus::MESSAGE_CALENDAR_BUSY) {
+			// One event that fulfills all status conditions is enough
+			// 1. Not an OOO event
+			// 2. Current user status (that is not a calendar status) was not set after the start of this event
+			// 3. Event is not set to be transparent
+			$count = count($applicableEvents);
+			$this->logger->debug("Found $count applicable event(s), changing user status", ['user' => $userId]);
+			$this->userStatusService->setUserStatus(
+				$userId,
+				IUserStatus::BUSY,
+				IUserStatus::MESSAGE_CALENDAR_BUSY,
+				true
+			);
+		}
+	}
+
+	private function getCalendarEvents(User $user): array {
+		$calendars = $this->calendarManager->getCalendarsForPrincipal('principals/users/' . $user->getUID());
+		if (empty($calendars)) {
+			return [];
+		}
+
+		$query = $this->calendarManager->newQuery('principals/users/' . $user->getUID());
+		foreach ($calendars as $calendarObject) {
+			// We can only work with a calendar if it exposes its scheduling information
+			if (!$calendarObject instanceof CalendarImpl) {
+				continue;
+			}
+
+			$sct = $calendarObject->getSchedulingTransparency();
+			if ($sct !== null && strtolower($sct->getValue()) == ScheduleCalendarTransp::TRANSPARENT) {
+				// If a calendar is marked as 'transparent', it means we must
+				// ignore it for free-busy purposes.
+				continue;
+			}
+			$query->addSearchCalendar($calendarObject->getUri());
+		}
+
+		$dtStart = DateTimeImmutable::createFromMutable($this->timeFactory->getDateTime());
+		$dtEnd = DateTimeImmutable::createFromMutable($this->timeFactory->getDateTime('+5 minutes'));
+
+		// Only query the calendars when there's any to search
+		if ($query instanceof CalendarQuery && !empty($query->getCalendarUris())) {
+			// Query the next hour
+			$query->setTimerangeStart($dtStart);
+			$query->setTimerangeEnd($dtEnd);
+			return $this->calendarManager->searchForPrincipal($query);
+		}
+
+		return [];
+	}
+}