fix(caldav): Add default reminder to attendees of scheduling messages

apps/dav/lib/CalDAV/Schedule/Plugin.php

@@ -11,6 +11,7 @@
 use OCA\DAV\CalDAV\CalendarHome;
 use OCA\DAV\CalDAV\DefaultCalendarValidator;
 use OCP\IConfig;
+use OCP\IUserManager;
 use Psr\Log\LoggerInterface;
 use Sabre\CalDAV\ICalendar;
 use Sabre\CalDAV\ICalendarObject;
@@ -21,6 +22,7 @@
 use Sabre\DAV\PropFind;
 use Sabre\DAV\Server;
 use Sabre\DAV\Xml\Property\LocalHref;
+use Sabre\DAVACL;
 use Sabre\DAVACL\IACL;
 use Sabre\DAVACL\IPrincipal;
 use Sabre\HTTP\RequestInterface;
@@ -44,6 +46,11 @@
 	 */
 	private $config;
 
+	/**
+	 * @var IUserManager
+	 */
+	private $userManager;
+
 	/** @var ITip\Message[] */
 	private $schedulingResponses = [];
 
@@ -58,10 +65,11 @@
 	/**
 	 * @param IConfig $config
 	 */
-	public function __construct(IConfig $config, LoggerInterface $logger, DefaultCalendarValidator $defaultCalendarValidator) {
+	public function __construct(IConfig $config, LoggerInterface $logger, DefaultCalendarValidator $defaultCalendarValidator, IUserManager $userManager) {
 		$this->config = $config;
 		$this->logger = $logger;
 		$this->defaultCalendarValidator = $defaultCalendarValidator;
+		$this->userManager = $userManager;
 	}
 
 	/**
@@ -229,7 +237,7 @@
 			$vevent->remove('VALARM');
 		}
 
-		parent::scheduleLocalDelivery($iTipMessage);
+		$this->scheduleLocalDeliveryHandler($iTipMessage);
 		// We only care when the message was successfully delivered locally
 		// Log all possible codes returned from the parent method that mean something went wrong
 		// 3.7, 3.8, 5.0, 5.2
@@ -444,6 +452,166 @@
 		}
 	}
 
+	/**
+	 * Event handler for the 'schedule' event.
+	 *
+	 * This handler attempts to look at local accounts to deliver the
+	 * scheduling object.
+	 *
+	 * @param ITip\Message $iTipMessage
+	 * @return void
+	 */
+	public function scheduleLocalDeliveryHandler(ITip\Message $iTipMessage)
+	{
+		$aclPlugin = $this->server->getPlugin('acl');
+
+		// Local delivery is not available if the ACL plugin is not loaded.
+		if (!$aclPlugin) {
+			return;
+		}
+
+		$caldavNS = '{'.self::NS_CALDAV.'}';
+
+		$principalUri = $aclPlugin->getPrincipalByUri($iTipMessage->recipient);
+		if (!$principalUri) {
+			$iTipMessage->scheduleStatus = '3.7;Could not find principal.';
+
+			return;
+		}
+
+		// We found a principal URL, now we need to find its inbox.
+		// Unfortunately we may not have sufficient privileges to find this, so
+		// we are temporarily turning off ACL to let this come through.
+		//
+		// Once we support PHP 5.5, this should be wrapped in a try..finally
+		// block so we can ensure that this privilege gets added again after.
+		$this->server->removeListener('propFind', [$aclPlugin, 'propFind']);
+
+		$result = $this->server->getProperties(
+			$principalUri,
+			[
+				'{DAV:}principal-URL',
+				 $caldavNS.'calendar-home-set',
+				 $caldavNS.'schedule-inbox-URL',
+				 $caldavNS.'schedule-default-calendar-URL',
+				'{http://sabredav.org/ns}email-address',
+			]
+		);
+
+		// Re-registering the ACL event
+		$this->server->on('propFind', [$aclPlugin, 'propFind'], 20);
+
+		if (!isset($result[$caldavNS.'schedule-inbox-URL'])) {
+			$iTipMessage->scheduleStatus = '5.2;Could not find local inbox';
+
+			return;
+		}
+		if (!isset($result[$caldavNS.'calendar-home-set'])) {
+			$iTipMessage->scheduleStatus = '5.2;Could not locate a calendar-home-set';
+
+			return;
+		}
+		if (!isset($result[$caldavNS.'schedule-default-calendar-URL'])) {
+			$iTipMessage->scheduleStatus = '5.2;Could not find a schedule-default-calendar-URL property';
+
+			return;
+		}
+
+		$calendarPath = $result[$caldavNS.'schedule-default-calendar-URL']->getHref();
+		$homePath = $result[$caldavNS.'calendar-home-set']->getHref();
+		$inboxPath = $result[$caldavNS.'schedule-inbox-URL']->getHref();
+
+		if ('REPLY' === $iTipMessage->method) {
+			$privilege = 'schedule-deliver-reply';
+		} else {
+			$privilege = 'schedule-deliver-invite';
+		}
+
+		if (!$aclPlugin->checkPrivileges($inboxPath, $caldavNS.$privilege, DAVACL\Plugin::R_PARENT, false)) {
+			$iTipMessage->scheduleStatus = '3.8;insufficient privileges: '.$privilege.' is required on the recipient schedule inbox.';
+
+			return;
+		}
+
+		// Next, we're going to find out if the item already exits in one of
+		// the users' calendars.
+		$uid = $iTipMessage->uid;
+
+		$newFileName = 'sabredav-'.\Sabre\DAV\UUIDUtil::getUUID().'.ics';
+
+		$home = $this->server->tree->getNodeForPath($homePath);
+		$inbox = $this->server->tree->getNodeForPath($inboxPath);
+
+		$currentObject = null;
+		$objectNode = null;
+		$oldICalendarData = null;
+		$isNewNode = false;
+
+		$result = $this->userManager->getByEmail($this->stripOffMailTo($iTipMessage->recipient));
+		$user = isset($result[0]) ? $result[0] : null;
+		if ($user) {
+			$userDefaultReminder = $this->config->getUserValue($user->getUID(), 'calendar', 'defaultReminder', 'none');
+			// If the user hasn't changed the default reminder, it will use the global one
+			if ($userDefaultReminder === 'none') {
+				$userDefaultReminder = $this->config->getAppValue('calendar', 'defaultReminder', 'none');
+			}
+			if ($userDefaultReminder !== 'none') {
+				$userDefaultReminder = intval($userDefaultReminder);
+				$this->createAlarm($iTipMessage, $userDefaultReminder);
+			}
+		}
+
+		$result = $home->getCalendarObjectByUID($uid);
+		if ($result) {
+			// There was an existing object, we need to update probably.
+			$objectPath = $homePath.'/'.$result;
+			$objectNode = $this->server->tree->getNodeForPath($objectPath);
+			$oldICalendarData = $objectNode->get();
+			$currentObject = Reader::read($oldICalendarData);
+		} else {
+			$isNewNode = true;
+		}
+
+		$broker = new ITip\Broker();
+		$newObject = $broker->processMessage($iTipMessage, $currentObject);
+
+		$inbox->createFile($newFileName, $iTipMessage->message->serialize());
+
+		if (!$newObject) {
+			// We received an iTip message referring to a UID that we don't
+			// have in any calendars yet, and processMessage did not give us a
+			// calendarobject back.
+			//
+			// The implication is that processMessage did not understand the
+			// iTip message.
+			$iTipMessage->scheduleStatus = '5.0;iTip message was not processed by the server, likely because we didn\'t understand it.';
+
+			return;
+		}
+
+		// Note that we are bypassing ACL on purpose by calling this directly.
+		// We may need to look a bit deeper into this later. Supporting ACL
+		// here would be nice.
+		if ($isNewNode) {
+			$calendar = $this->server->tree->getNodeForPath($calendarPath);
+			$calendar->createFile($newFileName, $newObject->serialize());
+		} else {
+			// If the message was a reply, we may have to inform other
+			// attendees of this attendees status. Therefore we're shooting off
+			// another itipMessage.
+			if ('REPLY' === $iTipMessage->method) {
+				$this->processICalendarChange(
+					$oldICalendarData,
+					$newObject,
+					[$iTipMessage->recipient],
+					[$iTipMessage->sender]
+				);
+			}
+			$objectNode->put($newObject->serialize());
+		}
+		$iTipMessage->scheduleStatus = '1.2;Message delivered locally';
+	}
+
 	/**
 	 * Returns a list of addresses that are associated with a principal.
 	 *
@@ -541,7 +709,7 @@
 		// and Sabre\CalDAV\Schedule\Plugin::getFreeBusyForEmail
 
 		$aclPlugin = $this->server->getPlugin('acl');
 		$this->server->removeListener('propFind', [$aclPlugin, 'propFind']);
 
 		$result = $aclPlugin->principalSearch(
 			['{http://sabredav.org/ns}email-address' => $this->stripOffMailTo($email)],
@@ -734,4 +902,39 @@
 			}
 		}
 	}
+
+	/**
+	 * Creates a VALARM inside an iTipMessage
+	 *
+	 * @param ITip\Message $iTipMessage
+	 * @param int $userDefaultReminder
+	 */
+	private function createAlarm(ITip\Message $iTipMessage, int $userDefaultReminder) {
+		$alarm = $iTipMessage->message->createComponent('VALARM');
+		$alarm->add($iTipMessage->message->createProperty('TRIGGER', '-' . $this->secondsToIso8601Duration(abs($userDefaultReminder)), ['RELATED' => 'START']));
+		$alarm->add($iTipMessage->message->createProperty('ACTION', 'DISPLAY'));
+		$iTipMessage->message->VEVENT->add($alarm);
+	}
+
+	/**
+	 * Converts seconds to an ISO 8601 duration string
+	 *
+	 * @param int $secs
+	 * @return string
+	 */
+	private function secondsToIso8601Duration(int $secs): string {
+		$day = 24 * 60 * 60;
+		$hour = 60 * 60;
+		$minute = 60;
+		if ($secs % $day === 0) {
+			return 'P' . $secs / $day . 'D';
+		}
+		if ($secs % $hour === 0) {
+			return 'PT' . $secs / $hour . 'H';
+		}
+		if ($secs % $minute === 0) {
+			return 'PT' . $secs / $minute . 'M';
+		}
+		return 'PT' . $secs . 'S';
+	}
 }

apps/dav/lib/Server.php

@@ -60,6 +60,7 @@
 use OCP\IConfig;
 use OCP\IPreview;
 use OCP\IRequest;
+use OCP\IUserManager;
 use OCP\IUserSession;
 use OCP\Profiler\IProfiler;
 use OCP\SabrePluginEvent;
@@ -162,7 +163,7 @@ public function __construct(IRequest $request, string $baseUri) {
 			$this->server->addPlugin(new DAV\Sharing\Plugin($authBackend, \OC::$server->getRequest(), \OC::$server->getConfig()));
 			$this->server->addPlugin(new \OCA\DAV\CalDAV\Plugin());
 			$this->server->addPlugin(new \OCA\DAV\CalDAV\ICSExportPlugin\ICSExportPlugin(\OC::$server->getConfig(), $logger));
-			$this->server->addPlugin(new \OCA\DAV\CalDAV\Schedule\Plugin(\OC::$server->getConfig(), \OC::$server->get(LoggerInterface::class), \OC::$server->get(DefaultCalendarValidator::class)));
+			$this->server->addPlugin(new \OCA\DAV\CalDAV\Schedule\Plugin(\OC::$server->getConfig(), \OC::$server->get(LoggerInterface::class), \OC::$server->get(DefaultCalendarValidator::class), \OC::$server->get(IUserManager::class)));
 
 			$this->server->addPlugin(\OC::$server->get(\OCA\DAV\CalDAV\Trashbin\Plugin::class));
 			$this->server->addPlugin(new \OCA\DAV\CalDAV\WebcalCaching\Plugin($request));