feat(dav): add systemtag object IDs listing

Signed-off-by: skjnldsv <skjnldsv@protonmail.com>

7 files changed, 154 insertions, 16 deletions

diff --git a/apps/dav/lib/RootCollection.php b/apps/dav/lib/RootCollection.php
index 6ede8cb683c..751ab17bb7a 100644
--- a/apps/dav/lib/RootCollection.php
+++ b/apps/dav/lib/RootCollection.php
@@ -105,11 +105,7 @@ class RootCollection extends SimpleCollection {
 
 		$publicCalendarRoot = new PublicCalendarRoot($caldavBackend, $l10n, $config, $logger);
 
-		$systemTagCollection = new SystemTagsByIdCollection(
-			\OC::$server->getSystemTagManager(),
-			\OC::$server->getUserSession(),
-			$groupManager
-		);
+		$systemTagCollection = Server::get(SystemTagsByIdCollection::class);
 		$systemTagRelationsCollection = new SystemTagsRelationsCollection(
 			\OC::$server->getSystemTagManager(),
 			\OC::$server->getSystemTagObjectMapper(),
diff --git a/apps/dav/lib/SystemTag/SystemTagNode.php b/apps/dav/lib/SystemTag/SystemTagNode.php
index 9357f207779..154bfa493f2 100644
--- a/apps/dav/lib/SystemTag/SystemTagNode.php
+++ b/apps/dav/lib/SystemTag/SystemTagNode.php
@@ -10,8 +10,8 @@ namespace OCA\DAV\SystemTag;
 use OCP\IUser;
 use OCP\SystemTag\ISystemTag;
 use OCP\SystemTag\ISystemTagManager;
+use OCP\SystemTag\ISystemTagObjectMapper;
 use OCP\SystemTag\TagAlreadyExistsException;
-
 use OCP\SystemTag\TagNotFoundException;
 use Sabre\DAV\Exception\Conflict;
 use Sabre\DAV\Exception\Forbidden;
@@ -21,7 +21,7 @@ use Sabre\DAV\Exception\NotFound;
 /**
  * DAV node representing a system tag, with the name being the tag id.
  */
-class SystemTagNode implements \Sabre\DAV\INode {
+class SystemTagNode implements \Sabre\DAV\ICollection {
 
 	protected int $numberOfFiles = -1;
 	protected int $referenceFileId = -1;
@@ -43,8 +43,9 @@ class SystemTagNode implements \Sabre\DAV\INode {
 		/**
 		 * Whether to allow permissions for admins
 		 */
-		protected $isAdmin,
+		protected bool $isAdmin,
 		protected ISystemTagManager $tagManager,
+		protected ISystemTagObjectMapper $tagMapper,
 	) {
 	}
 
@@ -164,4 +165,26 @@ class SystemTagNode implements \Sabre\DAV\INode {
 	public function setReferenceFileId(int $referenceFileId): void {
 		$this->referenceFileId = $referenceFileId;
 	}
+
+	public function createFile($name, $data = null) {
+		throw new MethodNotAllowed();
+	}
+	
+	public function createDirectory($name) {
+		throw new MethodNotAllowed();
+	}
+	
+	public function getChild($name) {
+		return new SystemTagObjectType($this->tag, $name, $this->tagManager, $this->tagMapper);
+	}
+	
+	public function childExists($name) {
+		$objectTypes = $this->tagMapper->getAvailableObjectTypes();
+		return in_array($name, $objectTypes);
+	}
+
+	public function getChildren() {
+		// We currently don't have a method to list allowed tag mappings types
+		return [new SystemTagObjectType($this->tag, 'files', $this->tagManager, $this->tagMapper)];
+	}
 }
diff --git a/apps/dav/lib/SystemTag/SystemTagObjectType.php b/apps/dav/lib/SystemTag/SystemTagObjectType.php
new file mode 100644
index 00000000000..0279e4411d8
--- /dev/null
+++ b/apps/dav/lib/SystemTag/SystemTagObjectType.php
@@ -0,0 +1,57 @@
+<?php
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+namespace OCA\DAV\SystemTag;
+
+use OCP\SystemTag\ISystemTag;
+use OCP\SystemTag\ISystemTagManager;
+use OCP\SystemTag\ISystemTagObjectMapper;
+use Sabre\DAV\Exception\MethodNotAllowed;
+
+/**
+ * SystemTagObjectType property
+ * This property represent a type of object which tags are assigned to.
+ */
+class SystemTagObjectType implements \Sabre\DAV\INode {
+	public const NS_NEXTCLOUD = 'http://nextcloud.org/ns';
+
+	/** @var string[] */
+	private array $objectsIds = [];
+
+	public function __construct(
+		private ISystemTag $tag,
+		private string $type,
+		private ISystemTagManager $tagManager,
+		private ISystemTagObjectMapper $tagMapper,
+	) {
+	}
+
+	/**
+	 * Get the list of object ids that have this tag assigned.
+	 */
+	public function getObjectsIds(): array {
+		if (empty($this->objectsIds)) {
+			$this->objectsIds = $this->tagMapper->getObjectIdsForTags($this->tag->getId(), $this->type);
+		}
+
+		return $this->objectsIds;
+	}
+
+	public function delete() {
+		throw new MethodNotAllowed();
+	}
+
+	public function getName() {
+		return $this->type;
+	}
+
+	public function setName($name) {
+		throw new MethodNotAllowed();
+	}
+
+	public function getLastModified() {
+		return null;
+	}
+}
diff --git a/apps/dav/lib/SystemTag/SystemTagPlugin.php b/apps/dav/lib/SystemTag/SystemTagPlugin.php
index 3c34f4263f6..687b47284eb 100644
--- a/apps/dav/lib/SystemTag/SystemTagPlugin.php
+++ b/apps/dav/lib/SystemTag/SystemTagPlugin.php
@@ -37,6 +37,7 @@ class SystemTagPlugin extends \Sabre\DAV\ServerPlugin {
 
 	// namespace
 	public const NS_OWNCLOUD = 'http://owncloud.org/ns';
+	public const NS_NEXTCLOUD = 'http://nextcloud.org/ns';
 	public const ID_PROPERTYNAME = '{http://owncloud.org/ns}id';
 	public const DISPLAYNAME_PROPERTYNAME = '{http://owncloud.org/ns}display-name';
 	public const USERVISIBLE_PROPERTYNAME = '{http://owncloud.org/ns}user-visible';
@@ -45,7 +46,8 @@ class SystemTagPlugin extends \Sabre\DAV\ServerPlugin {
 	public const CANASSIGN_PROPERTYNAME = '{http://owncloud.org/ns}can-assign';
 	public const SYSTEM_TAGS_PROPERTYNAME = '{http://nextcloud.org/ns}system-tags';
 	public const NUM_FILES_PROPERTYNAME = '{http://nextcloud.org/ns}files-assigned';
-	public const FILEID_PROPERTYNAME = '{http://nextcloud.org/ns}reference-fileid';
+	public const REFERENCE_FILEID_PROPERTYNAME = '{http://nextcloud.org/ns}reference-fileid';
+	public const OBJECTIDS_PROPERTYNAME = '{http://nextcloud.org/ns}object-ids';
 
 	/**
 	 * @var \Sabre\DAV\Server $server
@@ -202,7 +204,7 @@ class SystemTagPlugin extends \Sabre\DAV\ServerPlugin {
 			return;
 		}
 
-		if (!($node instanceof SystemTagNode) && !($node instanceof SystemTagMappingNode)) {
+		if (!($node instanceof SystemTagNode) && !($node instanceof SystemTagMappingNode) && !($node instanceof SystemTagObjectType)) {
 			return;
 		}
 
@@ -251,9 +253,25 @@ class SystemTagPlugin extends \Sabre\DAV\ServerPlugin {
 				return $node->getNumberOfFiles();
 			});
 
-			$propFind->handle(self::FILEID_PROPERTYNAME, function () use ($node): int {
+			$propFind->handle(self::REFERENCE_FILEID_PROPERTYNAME, function () use ($node): int {
 				return $node->getReferenceFileId();
 			});
+
+			$propFind->handle(self::OBJECTIDS_PROPERTYNAME, function () use ($node): SystemTagsObjectList {
+				$objectTypes = $this->tagMapper->getAvailableObjectTypes();
+				$objects = [];
+				foreach ($objectTypes as $type) {
+					$systemTagObjectType = new SystemTagObjectType($node->getSystemTag(), $type, $this->tagManager, $this->tagMapper);
+					$objects = array_merge($objects, array_fill_keys($systemTagObjectType->getObjectsIds(), $type));
+				}
+				return new SystemTagsObjectList($objects);
+			});
+		}
+
+		if ($node instanceof SystemTagObjectType) {
+			$propFind->handle(self::OBJECTIDS_PROPERTYNAME, function () use ($node): SystemTagsObjectList {
+				return new SystemTagsObjectList(array_fill_keys($node->getObjectsIds(), $node->getName()));
+			});
 		}
 	}
 
@@ -351,7 +369,7 @@ class SystemTagPlugin extends \Sabre\DAV\ServerPlugin {
 			self::USERASSIGNABLE_PROPERTYNAME,
 			self::GROUPS_PROPERTYNAME,
 			self::NUM_FILES_PROPERTYNAME,
-			self::FILEID_PROPERTYNAME,
+			self::REFERENCE_FILEID_PROPERTYNAME,
 		], function ($props) use ($node) {
 			$tag = $node->getSystemTag();
 			$name = $tag->getName();
@@ -388,7 +406,7 @@ class SystemTagPlugin extends \Sabre\DAV\ServerPlugin {
 				$this->tagManager->setTagGroups($tag, $groupIds);
 			}
 
-			if (isset($props[self::NUM_FILES_PROPERTYNAME]) || isset($props[self::FILEID_PROPERTYNAME])) {
+			if (isset($props[self::NUM_FILES_PROPERTYNAME]) || isset($props[self::REFERENCE_FILEID_PROPERTYNAME])) {
 				// read-only properties
 				throw new Forbidden();
 			}
diff --git a/apps/dav/lib/SystemTag/SystemTagsByIdCollection.php b/apps/dav/lib/SystemTag/SystemTagsByIdCollection.php
index cf889985d1b..b854db7b94d 100644
--- a/apps/dav/lib/SystemTag/SystemTagsByIdCollection.php
+++ b/apps/dav/lib/SystemTag/SystemTagsByIdCollection.php
@@ -11,6 +11,7 @@ use OCP\IGroupManager;
 use OCP\IUserSession;
 use OCP\SystemTag\ISystemTag;
 use OCP\SystemTag\ISystemTagManager;
+use OCP\SystemTag\ISystemTagObjectMapper;
 use OCP\SystemTag\TagNotFoundException;
 use Sabre\DAV\Exception\BadRequest;
 use Sabre\DAV\Exception\Forbidden;
@@ -30,6 +31,7 @@ class SystemTagsByIdCollection implements ICollection {
 		private ISystemTagManager $tagManager,
 		private IUserSession $userSession,
 		private IGroupManager $groupManager,
+		protected ISystemTagObjectMapper $tagMapper,
 	) {
 	}
 
@@ -162,6 +164,6 @@ class SystemTagsByIdCollection implements ICollection {
 	 * @return SystemTagNode
 	 */
 	private function makeNode(ISystemTag $tag) {
-		return new SystemTagNode($tag, $this->userSession->getUser(), $this->isAdmin(), $this->tagManager);
+		return new SystemTagNode($tag, $this->userSession->getUser(), $this->isAdmin(), $this->tagManager, $this->tagMapper);
 	}
 }
diff --git a/apps/dav/lib/SystemTag/SystemTagsInUseCollection.php b/apps/dav/lib/SystemTag/SystemTagsInUseCollection.php
index 6a3dd0c2155..c27926ec410 100644
--- a/apps/dav/lib/SystemTag/SystemTagsInUseCollection.php
+++ b/apps/dav/lib/SystemTag/SystemTagsInUseCollection.php
@@ -16,6 +16,7 @@ use OCP\Files\IRootFolder;
 use OCP\Files\NotPermittedException;
 use OCP\IUserSession;
 use OCP\SystemTag\ISystemTagManager;
+use OCP\SystemTag\ISystemTagObjectMapper;
 use Sabre\DAV\Exception\Forbidden;
 use Sabre\DAV\Exception\NotFound;
 use Sabre\DAV\SimpleCollection;
@@ -28,6 +29,7 @@ class SystemTagsInUseCollection extends SimpleCollection {
 		protected IUserSession $userSession,
 		protected IRootFolder $rootFolder,
 		protected ISystemTagManager $systemTagManager,
+		protected ISystemTagObjectMapper $tagMapper,
 		SystemTagsInFilesDetector $systemTagsInFilesDetector,
 		protected string $mediaType = '',
 	) {
@@ -46,7 +48,7 @@ class SystemTagsInUseCollection extends SimpleCollection {
 		if ($this->mediaType !== '') {
 			throw new NotFound('Invalid media type');
 		}
-		return new self($this->userSession, $this->rootFolder, $this->systemTagManager, $this->systemTagsInFilesDetector, $name);
+		return new self($this->userSession, $this->rootFolder, $this->systemTagManager, $this->tagMapper, $this->systemTagsInFilesDetector, $name);
 	}
 
 	/**
@@ -73,7 +75,7 @@ class SystemTagsInUseCollection extends SimpleCollection {
 		foreach ($result as $tagData) {
 			$tag = new SystemTag((string)$tagData['id'], $tagData['name'], (bool)$tagData['visibility'], (bool)$tagData['editable']);
 			// read only, so we can submit the isAdmin parameter as false generally
-			$node = new SystemTagNode($tag, $user, false, $this->systemTagManager);
+			$node = new SystemTagNode($tag, $user, false, $this->systemTagManager, $this->tagMapper);
 			$node->setNumberOfFiles((int)$tagData['number_files']);
 			$node->setReferenceFileId((int)$tagData['ref_file_id']);
 			$children[] = $node;
diff --git a/apps/dav/lib/SystemTag/SystemTagsObjectList.php b/apps/dav/lib/SystemTag/SystemTagsObjectList.php
new file mode 100644
index 00000000000..e25f1c804ee
--- /dev/null
+++ b/apps/dav/lib/SystemTag/SystemTagsObjectList.php
@@ -0,0 +1,40 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OCA\DAV\SystemTag;
+
+use Sabre\Xml\Writer;
+use Sabre\Xml\XmlSerializable;
+
+/**
+ * This property contains multiple "object-id" elements.
+ */
+class SystemTagsObjectList implements XmlSerializable {
+	public const NS_NEXTCLOUD = 'http://nextcloud.org/ns';
+
+	/**
+	 * @param array<string, string> $objects An array of object ids and their types
+	 */
+	public function __construct(
+		private array $objects,
+	) {	}
+
+	/**
+	 * The xmlSerialize method is called during xml writing.
+	 *
+	 * @param Writer $writer
+	 * @return void
+	 */
+	public function xmlSerialize(Writer $writer) {
+		foreach ($this->objects as $objectsId => $type) {
+			$writer->startElement('{' . self::NS_NEXTCLOUD . '}object-id');
+			$writer->writeElement('{' . self::NS_NEXTCLOUD . '}id', $objectsId);
+			$writer->writeElement('{' . self::NS_NEXTCLOUD . '}type', $type);
+			$writer->endElement();
+		}
+	}
+}