feat(files_reminders): Add propfind dav plugin

Signed-off-by: Christopher Ng <chrng8@gmail.com>

apps/files_reminders/appinfo/info.xml

@@ -13,6 +13,10 @@ Set file reminders.
 	<author>Christopher Ng</author>
 	<namespace>FilesReminders</namespace>
 
+	<types>
+		<dav />
+	</types>
+
 	<category>files</category>
 
 	<bugs>https://github.com/nextcloud/server/issues</bugs>
@@ -29,4 +33,10 @@ Set file reminders.
 	<commands>
 		<command>OCA\FilesReminders\Command\ListCommand</command>
 	</commands>
+
+	<sabre>
+		<plugins>
+			<plugin>OCA\FilesReminders\Dav\PropFindPlugin</plugin>
+		</plugins>
+	</sabre>
  </info>

apps/files_reminders/composer/composer/autoload_classmap.php

@@ -12,6 +12,7 @@
     'OCA\\FilesReminders\\BackgroundJob\\ScheduledNotifications' => $baseDir . '/../lib/BackgroundJob/ScheduledNotifications.php',
     'OCA\\FilesReminders\\Command\\ListCommand' => $baseDir . '/../lib/Command/ListCommand.php',
     'OCA\\FilesReminders\\Controller\\ApiController' => $baseDir . '/../lib/Controller/ApiController.php',
+    'OCA\\FilesReminders\\Dav\\PropFindPlugin' => $baseDir . '/../lib/Dav/PropFindPlugin.php',
     'OCA\\FilesReminders\\Db\\Reminder' => $baseDir . '/../lib/Db/Reminder.php',
     'OCA\\FilesReminders\\Db\\ReminderMapper' => $baseDir . '/../lib/Db/ReminderMapper.php',
     'OCA\\FilesReminders\\Exception\\NodeNotFoundException' => $baseDir . '/../lib/Exception/NodeNotFoundException.php',

apps/files_reminders/composer/composer/autoload_static.php

@@ -27,6 +27,7 @@ class ComposerStaticInitFilesReminders
         'OCA\\FilesReminders\\BackgroundJob\\ScheduledNotifications' => __DIR__ . '/..' . '/../lib/BackgroundJob/ScheduledNotifications.php',
         'OCA\\FilesReminders\\Command\\ListCommand' => __DIR__ . '/..' . '/../lib/Command/ListCommand.php',
         'OCA\\FilesReminders\\Controller\\ApiController' => __DIR__ . '/..' . '/../lib/Controller/ApiController.php',
+        'OCA\\FilesReminders\\Dav\\PropFindPlugin' => __DIR__ . '/..' . '/../lib/Dav/PropFindPlugin.php',
         'OCA\\FilesReminders\\Db\\Reminder' => __DIR__ . '/..' . '/../lib/Db/Reminder.php',
         'OCA\\FilesReminders\\Db\\ReminderMapper' => __DIR__ . '/..' . '/../lib/Db/ReminderMapper.php',
         'OCA\\FilesReminders\\Exception\\NodeNotFoundException' => __DIR__ . '/..' . '/../lib/Exception/NodeNotFoundException.php',

apps/files_reminders/lib/Dav/PropFindPlugin.php

@@ -0,0 +1,82 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2024 Christopher Ng <chrng8@gmail.com>
+ *
+ * @author Christopher Ng <chrng8@gmail.com>
+ *
+ * @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\FilesReminders\Dav;
+
+use DateTimeInterface;
+use OCA\DAV\Connector\Sabre\Node;
+use OCA\FilesReminders\Service\ReminderService;
+use OCP\AppFramework\Db\DoesNotExistException;
+use OCP\IUser;
+use OCP\IUserSession;
+use Sabre\DAV\INode;
+use Sabre\DAV\PropFind;
+use Sabre\DAV\Server;
+use Sabre\DAV\ServerPlugin;
+
+class PropFindPlugin extends ServerPlugin {
+
+	public const REMINDER_DUE_DATE_PROPERTY = '{http://nextcloud.org/ns}reminder-due-date';
+
+	public function __construct(
+		private ReminderService $reminderService,
+		private IUserSession $userSession,
+	) {
+	}
+
+	public function initialize(Server $server): void {
+		$server->on('propFind', [$this, 'propFind']);
+	}
+
+	public function propFind(PropFind $propFind, INode $node) {
+		if (!in_array(static::REMINDER_DUE_DATE_PROPERTY, $propFind->getRequestedProperties())) {
+			return;
+		}
+
+		if (!($node instanceof Node)) {
+			return;
+		}
+
+		$propFind->handle(
+			static::REMINDER_DUE_DATE_PROPERTY,
+			function () use ($node) {
+				$user = $this->userSession->getUser();
+				if (!($user instanceof IUser)) {
+					return '';
+				}
+
+				$fileId = $node->getId();
+				try {
+					$reminder = $this->reminderService->getDueForUser($user, $fileId);
+				} catch (DoesNotExistException $e) {
+					return '';
+				}
+
+				return $reminder->getDueDate()->format(DateTimeInterface::ATOM); // ISO 8601
+			},
+		);
+	}
+}