feat(dav): Add an activity focused selector for calendar events

It will show any event linked to a calendar directly owned by the
 logged-in user.

Signed-off-by: Côme Chilliet <come.chilliet@nextcloud.com>

Author: come-nc

apps/dav/composer/composer/autoload_classmap.php

@@ -32,6 +32,7 @@
     'OCA\\DAV\\BulkUpload\\BulkUploadPlugin' => $baseDir . '/../lib/BulkUpload/BulkUploadPlugin.php',
     'OCA\\DAV\\BulkUpload\\MultipartRequestParser' => $baseDir . '/../lib/BulkUpload/MultipartRequestParser.php',
     'OCA\\DAV\\CalDAV\\Activity\\Backend' => $baseDir . '/../lib/CalDAV/Activity/Backend.php',
+    'OCA\\DAV\\CalDAV\\Activity\\CalendarFocusedSelector' => $baseDir . '/../lib/CalDAV/Activity/CalendarFocusedSelector.php',
     'OCA\\DAV\\CalDAV\\Activity\\Filter\\Calendar' => $baseDir . '/../lib/CalDAV/Activity/Filter/Calendar.php',
     'OCA\\DAV\\CalDAV\\Activity\\Filter\\Todo' => $baseDir . '/../lib/CalDAV/Activity/Filter/Todo.php',
     'OCA\\DAV\\CalDAV\\Activity\\Provider\\Base' => $baseDir . '/../lib/CalDAV/Activity/Provider/Base.php',

apps/dav/composer/composer/autoload_static.php

@@ -47,6 +47,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\BulkUpload\\BulkUploadPlugin' => __DIR__ . '/..' . '/../lib/BulkUpload/BulkUploadPlugin.php',
         'OCA\\DAV\\BulkUpload\\MultipartRequestParser' => __DIR__ . '/..' . '/../lib/BulkUpload/MultipartRequestParser.php',
         'OCA\\DAV\\CalDAV\\Activity\\Backend' => __DIR__ . '/..' . '/../lib/CalDAV/Activity/Backend.php',
+        'OCA\\DAV\\CalDAV\\Activity\\CalendarFocusedSelector' => __DIR__ . '/..' . '/../lib/CalDAV/Activity/CalendarFocusedSelector.php',
         'OCA\\DAV\\CalDAV\\Activity\\Filter\\Calendar' => __DIR__ . '/..' . '/../lib/CalDAV/Activity/Filter/Calendar.php',
         'OCA\\DAV\\CalDAV\\Activity\\Filter\\Todo' => __DIR__ . '/..' . '/../lib/CalDAV/Activity/Filter/Todo.php',
         'OCA\\DAV\\CalDAV\\Activity\\Provider\\Base' => __DIR__ . '/..' . '/../lib/CalDAV/Activity/Provider/Base.php',

apps/dav/lib/AppInfo/Application.php

@@ -10,6 +10,7 @@
 
 namespace OCA\DAV\AppInfo;
 
+use OCA\DAV\CalDAV\Activity\CalendarFocusedSelector;
 use OCA\DAV\CalDAV\AppCalendar\AppCalendarPlugin;
 use OCA\DAV\CalDAV\CachedSubscriptionProvider;
 use OCA\DAV\CalDAV\CalendarManager;
@@ -243,6 +244,8 @@ public function register(IRegistrationContext $context): void {
 		$context->registerEventListener(DeclarativeSettingsSetValueEvent::class, DavAdminSettingsListener::class);
 
 		$context->registerConfigLexicon(ConfigLexicon::class);
+
+		$context->registerActivityFocusedSelector(CalendarFocusedSelector::class);
 	}
 
 	#[\Override]

apps/dav/lib/CalDAV/Activity/CalendarFocusedSelector.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\DAV\CalDAV\Activity;
+
+use OCP\Activity\IActivityFocusedSelector;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+
+class CalendarFocusedSelector implements IActivityFocusedSelector {
+	#[\Override]
+	public function extendQuery(IQueryBuilder $query, string $userId): array {
+		// Activity related to calendars owned by the user
+		$query->leftJoin('a', 'calendars', 'calendars',
+			$query->expr()->andX(
+				$query->expr()->eq('a.object_type', $query->createNamedParameter('calendar')),
+				$query->expr()->eq('a.object_id', 'calendars.id'),
+			));
+		return [
+			$query->expr()->eq('calendars.principaluri', $query->createNamedParameter('principals/users/' . $userId)),
+		];
+	}
+}

lib/public/Activity/IActivityFocusedSelector.php

@@ -10,7 +10,9 @@
 namespace OCP\Activity;
 
 use OCP\AppFramework\Attribute\Implementable;
+use OCP\DB\QueryBuilder\ICompositeExpression;
 use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\DB\QueryBuilder\IQueryFunction;
 
 /**
  * @since 35.0.0
@@ -21,7 +23,7 @@ interface IActivityFocusedSelector {
 	 * Extend query with joins if needed, and return an array of conditions to add
 	 * in the OR clause of the WHERE for filtering focused activity events
 	 *
-	 * @return list<string> conditions to add in the where clause
+	 * @return list<string|ICompositeExpression|IQueryFunction> conditions to add in the where clause
 	 * @since 35.0.0
 	 */
 	public function extendQuery(IQueryBuilder $query, string $userId): array;