Correctly listen to group change events

lib/Album/AlbumMapper.php

@@ -273,6 +273,22 @@ public function removeFile(int $albumId, int $fileId): void {
 		$query->executeStatement();
 	}
 
+	public function removeFilesForUser(int $albumId, string $userId) {
+		// Remove all photos by this user from the album:
+		$query = $this->connection->getQueryBuilder();
+		$query->delete('photos_albums_files')
+			->where($query->expr()->eq('album_id', $query->createNamedParameter($albumId, IQueryBuilder::PARAM_INT)))
+			->andWhere($query->expr()->eq('owner', $query->createNamedParameter($userId)))
+			->executeStatement();
+
+		// Update the last added photo:
+		$query = $this->connection->getQueryBuilder();
+		$query->update("photos_albums")
+			->set('last_added_photo', $query->createNamedParameter($this->getLastAdded($albumId), IQueryBuilder::PARAM_INT))
+			->where($query->expr()->eq('album_id', $query->createNamedParameter($albumId, IQueryBuilder::PARAM_INT)))
+			->executeStatement();
+	}
+
 	private function getLastAdded(int $albumId): int {
 		$query = $this->connection->getQueryBuilder();
 		$query->select("file_id")
@@ -428,6 +444,34 @@ function computeKey($c) {
 		$this->connection->commit();
 	}
 
+	/**
+	 * @param string $collaboratorId
+	 * @param int $collaboratorType
+	 * @return AlbumInfo[]
+	 */
+	public function getSharedAlbumsForCollaborator(string $collaboratorId, int $collaboratorType): array {
+		$query = $this->connection->getQueryBuilder();
+		$rows = $query
+			->select("a.album_id", "name", "user", "location", "created", "last_added_photo")
+			->from("photos_albums_collabs", "c")
+			->leftJoin("c", "photos_albums", "a", $query->expr()->eq("a.album_id", "c.album_id"))
+			->where($query->expr()->eq('collaborator_id', $query->createNamedParameter($collaboratorId)))
+			->andWhere($query->expr()->eq('collaborator_type', $query->createNamedParameter($collaboratorType, IQueryBuilder::PARAM_INT)))
+			->executeQuery()
+			->fetchAll();
+
+		return array_map(function (array $row) {
+			return new AlbumInfo(
+				(int)$row['album_id'],
+				$row['user'],
+				$row['name'].' ('.$row['user'].')',
+				$row['location'],
+				(int)$row['created'],
+				(int)$row['last_added_photo']
+			);
+		}, $rows);
+	}
+
 	/**
 	 * @param string $collaboratorId
 	 * @param string $collaboratorsType - The type of the collaborator, either a user or a group.
@@ -483,7 +527,6 @@ public function getSharedAlbumsForCollaboratorWithFiles(string $collaboratorId,
 	 * @return void
 	 */
 	public function deleteUserFromAlbumCollaboratorsList(string $userId, int $albumId): void {
-		// TODO: only delete if this was not a group share
 		$query = $this->connection->getQueryBuilder();
 		$query->delete('photos_albums_collabs')
 			->where($query->expr()->eq('album_id', $query->createNamedParameter($albumId, IQueryBuilder::PARAM_INT)))
@@ -492,17 +535,20 @@ public function deleteUserFromAlbumCollaboratorsList(string $userId, int $albumI
 			->executeStatement();
 
 		// Remove all photos by this user from the album:
-		$query = $this->connection->getQueryBuilder();
-		$query->delete('photos_albums_files')
-			->where($query->expr()->eq('album_id', $query->createNamedParameter($albumId, IQueryBuilder::PARAM_INT)))
-			->andWhere($query->expr()->eq('owner', $query->createNamedParameter($userId)))
-			->executeStatement();
+		$this->removeFilesForUser($albumId, $userId);
+	}
 
-		// Update the last added photo:
+	/**
+	 * @param string $groupId
+	 * @param int $albumId
+	 * @return void
+	 */
+	public function deleteGroupFromAlbumCollaboratorsList(string $groupId, int $albumId): void {
 		$query = $this->connection->getQueryBuilder();
-		$query->update("photos_albums")
-			->set('last_added_photo', $query->createNamedParameter($this->getLastAdded($albumId), IQueryBuilder::PARAM_INT))
+		$query->delete('photos_albums_collabs')
 			->where($query->expr()->eq('album_id', $query->createNamedParameter($albumId, IQueryBuilder::PARAM_INT)))
+			->andWhere($query->expr()->eq('collaborator_id', $query->createNamedParameter($groupId)))
+			->andWhere($query->expr()->eq('collaborator_type', $query->createNamedParameter(self::TYPE_GROUP, IQueryBuilder::PARAM_INT)))
 			->executeStatement();
 	}
 

lib/AppInfo/Application.php

@@ -29,11 +29,15 @@
 use OCA\Photos\Listener\SabrePluginAuthInitListener;
 use OCA\DAV\Connector\Sabre\Principal;
 use OCA\Photos\Listener\NodeDeletedListener;
+use OCA\Photos\Listener\GroupUserRemovedListener;
+use OCA\Photos\Listener\GroupDeletedListener;
 use OCP\AppFramework\App;
 use OCP\AppFramework\Bootstrap\IBootContext;
 use OCP\AppFramework\Bootstrap\IBootstrap;
 use OCP\AppFramework\Bootstrap\IRegistrationContext;
 use OCP\Files\Events\Node\NodeDeletedEvent;
+use OCP\Group\Events\UserRemovedEvent;
+use OCP\Group\Events\GroupDeletedEvent;
 
 class Application extends App implements IBootstrap {
 	public const APP_ID = 'photos';
@@ -65,7 +69,13 @@ public function __construct() {
 	public function register(IRegistrationContext $context): void {
 		/** Register $principalBackend for the DAV collection */
 		$context->registerServiceAlias('principalBackend', Principal::class);
+
 		$context->registerEventListener(NodeDeletedEvent::class, NodeDeletedListener::class);
+
+		$context->registerEventListener(UserRemovedEvent::class, GroupUserRemovedListener::class);
+
+		$context->registerEventListener(GroupDeletedEvent::class, GroupDeletedListener::class);
+
 		$context->registerEventListener(SabrePluginAuthInitEvent::class, SabrePluginAuthInitListener::class);
 	}
 

lib/Listener/GroupDeletedListener.php

@@ -0,0 +1,47 @@
+<?php
+
+namespace OCA\Photos\Listener;
+
+use OCA\Photos\Album\AlbumMapper;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Group\Events\GroupDeletedEvent;
+
+class GroupDeletedListener implements IEventListener {
+	private AlbumMapper $albumMapper;
+
+	public function __construct(AlbumMapper $albumMapper) {
+		$this->albumMapper = $albumMapper;
+	}
+
+	public function handle(Event $event): void {
+		if (!($event instanceof GroupDeletedEvent)) {
+			return;
+		}
+
+		// Get all shared albums for this group:
+		$albums_group = $this->albumMapper->getSharedAlbumsForCollaborator($event->getGroup()->getGID(), AlbumMapper::TYPE_GROUP);
+
+		// Get all users of this group:
+		$users = $event->getGroup()->getUsers();
+
+		foreach ($users as $user) {
+			$uid = $user->getUID();
+
+			// Get all albums shared with this specific user:
+			$albums_user = $this->albumMapper->getSharedAlbumsForCollaborator($user->getUID(), AlbumMapper::TYPE_USER);
+
+			// Get all group-shared albums that are not directly shared with the removed user in addition
+			$albums = array_udiff($albums_group, $albums_user, fn ($a, $b) => ($a->getId() - $b->getId()));
+
+			// Remove their photos from theses albums:
+			foreach ($albums as $album) {
+				$this->albumMapper->removeFilesForUser($album->getId(), $user->getUID());
+			}
+		}
+
+		foreach ($albums_group as $album) {
+			$this->albumMapper->deleteGroupFromAlbumCollaboratorsList($event->getGroup()->getGID(), $album->getId());
+		}
+	}
+}

lib/Listener/GroupUserRemovedListener.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace OCA\Photos\Listener;
+
+use OCA\Photos\Album\AlbumMapper;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Group\Events\UserRemovedEvent;
+
+class GroupUserRemovedListener implements IEventListener {
+	private AlbumMapper $albumMapper;
+
+	public function __construct(AlbumMapper $albumMapper) {
+		$this->albumMapper = $albumMapper;
+	}
+
+	public function handle(Event $event): void {
+		if (!($event instanceof UserRemovedEvent)) {
+			return;
+		}
+
+		// Get all shared albums for this group:
+		$albums_group = $this->albumMapper->getSharedAlbumsForCollaborator($event->getGroup()->getGID(), AlbumMapper::TYPE_GROUP);
+		// Get all albums shared with this specific user:
+		$albums_user = $this->albumMapper->getSharedAlbumsForCollaborator($event->getUser()->getUID(), AlbumMapper::TYPE_USER);
+		// Get all group-shared albums that are not directly shared with the removed user in addition
+		$albums = array_udiff($albums_group, $albums_user, fn ($a, $b) => ($a->getId() - $b->getId()));
+
+		// Remove their photos from theses albums:
+		foreach ($albums as $album) {
+			$this->albumMapper->removeFilesForUser($album->getId(), $event->getUser()->getUID());
+		}
+	}
+}