feat(user status): automate user status for events

and automatically set a user status to free or busy depending on their calendar
transparency, event status and availability settings

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

5 files changed, 366 insertions, 0 deletions

diff --git a/apps/dav/lib/CalDAV/CalendarImpl.php b/apps/dav/lib/CalDAV/CalendarImpl.php
index cc57aa36469..de20c9ac3ae 100644
--- a/apps/dav/lib/CalDAV/CalendarImpl.php
+++ b/apps/dav/lib/CalDAV/CalendarImpl.php
@@ -33,11 +33,15 @@ use OCA\DAV\CalDAV\InvitationResponse\InvitationResponseServer;
 use OCP\Calendar\Exceptions\CalendarException;
 use OCP\Calendar\ICreateFromString;
 use OCP\Calendar\IHandleImipMessage;
+use OCP\Calendar\ISchedulingInformation;
 use OCP\Constants;
+use Sabre\CalDAV\Xml\Property\ScheduleCalendarTransp;
 use Sabre\DAV\Exception\Conflict;
 use Sabre\VObject\Component\VCalendar;
 use Sabre\VObject\Component\VEvent;
+use Sabre\VObject\Component\VTimeZone;
 use Sabre\VObject\ITip\Message;
+use Sabre\VObject\Property;
 use Sabre\VObject\Reader;
 use function Sabre\Uri\split as uriSplit;
 
@@ -86,6 +90,29 @@ class CalendarImpl implements ICreateFromString, IHandleImipMessage {
 		return $this->calendarInfo['{http://apple.com/ns/ical/}calendar-color'];
 	}
 
+	public function getSchedulingTransparency(): ?ScheduleCalendarTransp {
+		return $this->calendarInfo['{' . \OCA\DAV\CalDAV\Schedule\Plugin::NS_CALDAV . '}schedule-calendar-transp'];
+	}
+
+	public function getSchedulingTimezone(): ?VTimeZone {
+		$tzProp = '{' . \OCA\DAV\CalDAV\Schedule\Plugin::NS_CALDAV . '}calendar-timezone';
+		if (!isset($this->calendarInfo[$tzProp])) {
+			return null;
+		}
+		// This property contains a VCALENDAR with a single VTIMEZONE
+		/** @var string $timezoneProp */
+		$timezoneProp = $this->calendarInfo[$tzProp];
+		/** @var VCalendar $vobj */
+		$vobj = Reader::read($timezoneProp);
+		$components = $vobj->getComponents();
+		if(empty($components)) {
+			return null;
+		}
+		/** @var VTimeZone $vtimezone */
+		$vtimezone = $components[0];
+		return $vtimezone;
+	}
+
 	/**
 	 * @param string $pattern which should match within the $searchProperties
 	 * @param array $searchProperties defines the properties within the query pattern should match
diff --git a/apps/dav/lib/CalDAV/FreeBusy/FreeBusyGenerator.php b/apps/dav/lib/CalDAV/FreeBusy/FreeBusyGenerator.php
new file mode 100644
index 00000000000..29daca4e092
--- /dev/null
+++ b/apps/dav/lib/CalDAV/FreeBusy/FreeBusyGenerator.php
@@ -0,0 +1,44 @@
+<?php
+declare(strict_types=1);
+/*
+ * *
+ *  *
+ *  * @copyright 2023 Anna Larch <anna.larch@gmx.net>
+ *  *
+ *  * @author Anna Larch <anna.larch@gmx.net>
+ *  *
+ *  * This library is free software; you can redistribute it and/or
+ *  * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ *  * License as published by the Free Software Foundation; either
+ *  * version 3 of the License, or any later version.
+ *  *
+ *  * This library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ *  *
+ *
+ */
+
+namespace OCA\DAV\CalDAV\FreeBusy;
+
+use DateTimeInterface;
+use DateTimeZone;
+use Sabre\VObject\Component\VCalendar;
+
+/**
+ * @psalm-suppress PropertyNotSetInConstructor
+ */
+class FreeBusyGenerator extends \Sabre\VObject\FreeBusyGenerator {
+
+	public function __construct() {
+		parent::__construct();
+	}
+
+	public function getVCalendar(): VCalendar {
+		return new VCalendar();
+	}
+}
diff --git a/apps/dav/lib/CalDAV/Schedule/Plugin.php b/apps/dav/lib/CalDAV/Schedule/Plugin.php
index 2845ccdf6c2..16acc72d988 100644
--- a/apps/dav/lib/CalDAV/Schedule/Plugin.php
+++ b/apps/dav/lib/CalDAV/Schedule/Plugin.php
@@ -36,6 +36,7 @@ use OCA\DAV\CalDAV\CalendarHome;
 use OCP\IConfig;
 use Psr\Log\LoggerInterface;
 use Sabre\CalDAV\ICalendar;
+use Sabre\CalDAV\Schedule\IOutbox;
 use Sabre\DAV\INode;
 use Sabre\DAV\IProperties;
 use Sabre\DAV\PropFind;
@@ -44,6 +45,7 @@ use Sabre\DAV\Xml\Property\LocalHref;
 use Sabre\DAVACL\IPrincipal;
 use Sabre\HTTP\RequestInterface;
 use Sabre\HTTP\ResponseInterface;
+use Sabre\VObject;
 use Sabre\VObject\Component;
 use Sabre\VObject\Component\VCalendar;
 use Sabre\VObject\Component\VEvent;
diff --git a/apps/dav/lib/CalDAV/Status/Status.php b/apps/dav/lib/CalDAV/Status/Status.php
new file mode 100644
index 00000000000..8857d0f14e7
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Status/Status.php
@@ -0,0 +1,57 @@
+<?php
+/*
+ * *
+ *  * Dav App
+ *  *
+ *  * @copyright 2023 Anna Larch <anna.larch@gmx.net>
+ *  *
+ *  * @author Anna Larch <anna.larch@gmx.net>
+ *  *
+ *  * This library is free software; you can redistribute it and/or
+ *  * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ *  * License as published by the Free Software Foundation; either
+ *  * version 3 of the License, or any later version.
+ *  *
+ *  * This library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ *  *
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Status;
+
+class Status {
+
+	public function __construct(private string $status = '', private ?string $message = null, private ?string $customMessage = null){}
+
+	public function getStatus(): string {
+		return $this->status;
+	}
+
+	public function setStatus(string $status): void {
+		$this->status = $status;
+	}
+
+	public function getMessage(): ?string {
+		return $this->message;
+	}
+
+	public function setMessage(?string $message): void {
+		$this->message = $message;
+	}
+
+	public function getCustomMessage(): ?string {
+		return $this->customMessage;
+	}
+
+	public function setCustomMessage(?string $customMessage): void {
+		$this->customMessage = $customMessage;
+	}
+
+
+}
diff --git a/apps/dav/lib/CalDAV/Status/StatusService.php b/apps/dav/lib/CalDAV/Status/StatusService.php
new file mode 100644
index 00000000000..92554f800c3
--- /dev/null
+++ b/apps/dav/lib/CalDAV/Status/StatusService.php
@@ -0,0 +1,236 @@
+<?php
+/*
+ * *
+ *  * Dav App
+ *  *
+ *  * @copyright 2023 Anna Larch <anna.larch@gmx.net>
+ *  *
+ *  * @author Anna Larch <anna.larch@gmx.net>
+ *  *
+ *  * This library is free software; you can redistribute it and/or
+ *  * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ *  * License as published by the Free Software Foundation; either
+ *  * version 3 of the License, or any later version.
+ *  *
+ *  * This library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ *  *
+ *
+ */
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2023 Anna Larch <anna.larch@gmx.net>
+ *
+ * @author Anna Larch <anna.larch@gmx.net>
+ *
+ * @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\Status;
+
+use DateTimeZone;
+use OC\Calendar\CalendarQuery;
+use OCA\DAV\CalDAV\CalendarImpl;
+use OCA\DAV\CalDAV\FreeBusy\FreeBusyGenerator;
+use OCA\DAV\CalDAV\InvitationResponse\InvitationResponseServer;
+use OCA\DAV\CalDAV\IUser;
+use OCA\DAV\CalDAV\Schedule\Plugin as SchedulePlugin;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\Calendar\IManager;
+use OCP\Calendar\ISchedulingInformation;
+use OCP\IL10N;
+use OCP\IUser as User;
+use OCP\UserStatus\IUserStatus;
+use Sabre\CalDAV\Xml\Property\ScheduleCalendarTransp;
+use Sabre\DAV\Exception\NotAuthenticated;
+use Sabre\DAVACL\Exception\NeedPrivileges;
+use Sabre\DAVACL\Plugin as AclPlugin;
+use Sabre\VObject\Component;
+use Sabre\VObject\Component\VCalendar;
+use Sabre\VObject\Component\VEvent;
+use Sabre\VObject\Parameter;
+use Sabre\VObject\Property;
+use Sabre\VObject\Reader;
+
+class StatusService {
+	public function __construct(private ITimeFactory $timeFactory,
+								private IManager $calendarManager,
+								private InvitationResponseServer $server,
+								private IL10N $l10n,
+								private FreeBusyGenerator $generator){}
+
+	public function processCalendarAvailability(User $user, ?string $availability): ?Status {
+		$userId = $user->getUID();
+		$email = $user->getEMailAddress();
+		if($email === null) {
+			return null;
+		}
+
+		$server = $this->server->getServer();
+
+		/** @var SchedulePlugin $schedulingPlugin */
+		$schedulingPlugin = $server->getPlugin('caldav-schedule');
+		$caldavNS = '{'.$schedulingPlugin::NS_CALDAV.'}';
+
+		/** @var AclPlugin $aclPlugin */
+		$aclPlugin = $server->getPlugin('acl');
+		if ('mailto:' === substr($email, 0, 7)) {
+			$email = substr($email, 7);
+		}
+
+		$result = $aclPlugin->principalSearch(
+			['{http://sabredav.org/ns}email-address' => $email],
+			[
+				'{DAV:}principal-URL',
+				$caldavNS.'calendar-home-set',
+				$caldavNS.'schedule-inbox-URL',
+				'{http://sabredav.org/ns}email-address',
+			]
+		);
+
+		if (!count($result) || !isset($result[0][200][$caldavNS.'schedule-inbox-URL'])) {
+			return null;
+		}
+
+		$inboxUrl = $result[0][200][$caldavNS.'schedule-inbox-URL']->getHref();
+
+		// Do we have permission?
+		try {
+			$aclPlugin->checkPrivileges($inboxUrl, $caldavNS.'schedule-query-freebusy');
+		} catch (NeedPrivileges | NotAuthenticated $exception) {
+			return null;
+		}
+
+		$now = $this->timeFactory->now();
+		$calendarTimeZone = $now->getTimezone();
+		$calendars = $this->calendarManager->getCalendarsForPrincipal('principals/users/' . $userId);
+		if(empty($calendars)) {
+			return null;
+		}
+
+		$query = $this->calendarManager->newQuery('principals/users/' . $userId);
+		foreach ($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 && ScheduleCalendarTransp::TRANSPARENT == strtolower($sct->getValue())) {
+				// If a calendar is marked as 'transparent', it means we must
+				// ignore it for free-busy purposes.
+				continue;
+			}
+
+			/** @var Component\VTimeZone|null $ctz */
+			$ctz = $calendarObject->getSchedulingTimezone();
+			if ($ctz !== null) {
+				$calendarTimeZone = $ctz->getTimeZone();
+			}
+			$query->addSearchCalendar($calendarObject->getUri());
+		}
+
+		$calendarEvents = [];
+		$dtStart = $now;
+		$dtEnd = \DateTimeImmutable::createFromMutable($this->timeFactory->getDateTime('+10 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);
+			$calendarEvents = $this->calendarManager->searchForPrincipal($query);
+		}
+
+		// @todo we can cache that
+		if(empty($availability) && empty($calendarEvents)) {
+			// No availability settings and no calendar events, we can stop here
+			return null;
+		}
+
+		$calendar = $this->generator->getVCalendar();
+		foreach ($calendarEvents as $calendarEvent) {
+			$vEvent = new VEvent($calendar, 'VEVENT');
+			foreach($calendarEvent['objects'] as $component) {
+				foreach ($component as $key =>  $value) {
+					$vEvent->add($key, $value[0]);
+				}
+			}
+			$calendar->add($vEvent);
+		}
+
+		$calendar->METHOD = 'REQUEST';
+
+		$this->generator->setObjects($calendar);
+		$this->generator->setTimeRange($dtStart, $dtEnd);
+		$this->generator->setTimeZone($calendarTimeZone);
+
+		if (!empty($availability)) {
+			$this->generator->setVAvailability(
+				Reader::read(
+					$availability
+				)
+			);
+		}
+		// Generate the intersection of VAVILABILITY and all VEVENTS in all calendars
+		$result = $this->generator->getResult();
+
+		if (!isset($result->VFREEBUSY)) {
+			return null;
+		}
+
+		/** @var Component $freeBusyComponent */
+		$freeBusyComponent = $result->VFREEBUSY;
+		$freeBusyProperties = $freeBusyComponent->select('FREEBUSY');
+		// If there is no FreeBusy property, the time-range is empty and available
+		// so set the status to online as otherwise we will never recover from a BUSY status
+		if (count($freeBusyProperties) === 0) {
+			return new Status(IUserStatus::ONLINE);
+		}
+
+		/** @var Property $freeBusyProperty */
+		$freeBusyProperty = $freeBusyProperties[0];
+		if (!$freeBusyProperty->offsetExists('FBTYPE')) {
+			// If there is no FBTYPE, it means it's busy from a regular event
+			return new Status(IUserStatus::BUSY, IUserStatus::MESSAGE_CALENDAR_BUSY);
+		}
+
+		// If we can't deal with the FBTYPE (custom properties are a possibility)
+		// we should ignore it and leave the current status
+		$fbTypeParameter = $freeBusyProperty->offsetGet('FBTYPE');
+		if (!($fbTypeParameter instanceof Parameter)) {
+			return null;
+		}
+		$fbType = $fbTypeParameter->getValue();
+		switch ($fbType) {
+			case 'BUSY':
+				return new Status(IUserStatus::BUSY, IUserStatus::MESSAGE_CALENDAR_BUSY, $this->l10n->t('In a meeting'));
+			case 'BUSY-UNAVAILABLE':
+				return new Status(IUserStatus::AWAY, IUserStatus::MESSAGE_AVAILABILITY);
+			case 'BUSY-TENTATIVE':
+				return new Status(IUserStatus::AWAY, IUserStatus::MESSAGE_CALENDAR_BUSY_TENTATIVE);
+			default:
+				return null;
+		}
+	}
+}