refactor: remove SystemTag logic from Folder into QuerySearchHelper

- adds OC\SystemTag\SystemTagsInFilesDetector where the search logic is
  moved to

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>

3 files changed, 108 insertions, 52 deletions

diff --git a/lib/private/Files/Cache/QuerySearchHelper.php b/lib/private/Files/Cache/QuerySearchHelper.php
index af198e9c832..f540f2dcb65 100644
--- a/lib/private/Files/Cache/QuerySearchHelper.php
+++ b/lib/private/Files/Cache/QuerySearchHelper.php
@@ -25,13 +25,18 @@
  */
 namespace OC\Files\Cache;
 
+use OC\Files\Cache\Wrapper\CacheJail;
+use OC\Files\Node\Root;
 use OC\Files\Search\QueryOptimizer\QueryOptimizer;
 use OC\Files\Search\SearchBinaryOperator;
 use OC\SystemConfig;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\Files\Cache\ICache;
 use OCP\Files\Cache\ICacheEntry;
+use OCP\Files\Folder;
 use OCP\Files\IMimeTypeLoader;
+use OCP\Files\IRootFolder;
+use OCP\Files\Mount\IMountPoint;
 use OCP\Files\Search\ISearchBinaryOperator;
 use OCP\Files\Search\ISearchQuery;
 use OCP\IDBConnection;
@@ -190,4 +195,38 @@ class QuerySearchHelper {
 		}
 		return $results;
 	}
+
+	/**
+	 * @return array{array<string, ICache>, array<string, IMountPoint>}
+	 */
+	public function getCachesAndMountPointsForSearch(Root $root, string $path, bool $limitToHome = false): array {
+		$rootLength = strlen($path);
+		$mount = $root->getMount($path);
+		$storage = $mount->getStorage();
+		$internalPath = $mount->getInternalPath($path);
+
+		if ($internalPath !== '') {
+			// a temporary CacheJail is used to handle filtering down the results to within this folder
+			$caches = ['' => new CacheJail($storage->getCache(''), $internalPath)];
+		} else {
+			$caches = ['' => $storage->getCache('')];
+		}
+		$mountByMountPoint = ['' => $mount];
+
+		if (!$limitToHome) {
+			/** @var IMountPoint[] $mounts */
+			$mounts = $root->getMountsIn($path);
+			foreach ($mounts as $mount) {
+				$storage = $mount->getStorage();
+				if ($storage) {
+					$relativeMountPoint = ltrim(substr($mount->getMountPoint(), $rootLength), '/');
+					$caches[$relativeMountPoint] = $storage->getCache('');
+					$mountByMountPoint[$relativeMountPoint] = $mount;
+				}
+			}
+		}
+
+		return [$caches, $mountByMountPoint];
+	}
+
 }
diff --git a/lib/private/Files/Node/Folder.php b/lib/private/Files/Node/Folder.php
index 2890ca6fcf6..1d6d88bafe6 100644
--- a/lib/private/Files/Node/Folder.php
+++ b/lib/private/Files/Node/Folder.php
@@ -33,7 +33,6 @@ namespace OC\Files\Node;
 
 use OC\Files\Cache\QuerySearchHelper;
 use OC\Files\Search\SearchBinaryOperator;
-use OC\Files\Cache\Wrapper\CacheJail;
 use OC\Files\Search\SearchComparison;
 use OC\Files\Search\SearchOrder;
 use OC\Files\Search\SearchQuery;
@@ -216,37 +215,6 @@ class Folder extends Node implements \OCP\Files\Folder {
 	}
 
 	/**
-	 * @psalm-return list{0: array<string, \OCP\Files\Cache\ICache>, 1: array<string, \OCP\Files\Mount\IMountPoint>}
-	 */
-	protected function getCachesAndMountpointsForSearch(bool $limitToHome = false): array {
-		$rootLength = strlen($this->path);
-		$mount = $this->root->getMount($this->path);
-		$storage = $mount->getStorage();
-		$internalPath = $mount->getInternalPath($this->path);
-		if ($internalPath !== '') {
-			// a temporary CacheJail is used to handle filtering down the results to within this folder
-			$caches = ['' => new CacheJail($storage->getCache(''), $internalPath)];
-		} else {
-			$caches = ['' => $storage->getCache('')];
-		}
-		$mountByMountPoint = ['' => $mount];
-
-		if (!$limitToHome) {
-			$mounts = $this->root->getMountsIn($this->path);
-			foreach ($mounts as $mount) {
-				$storage = $mount->getStorage();
-				if ($storage) {
-					$relativeMountPoint = ltrim(substr($mount->getMountPoint(), $rootLength), '/');
-					$caches[$relativeMountPoint] = $storage->getCache('');
-					$mountByMountPoint[$relativeMountPoint] = $mount;
-				}
-			}
-		}
-
-		return [$caches, $mountByMountPoint];
-	}
-
-	/**
 	 * search for files with the name matching $query
 	 *
 	 * @param string|ISearchQuery $query
@@ -265,10 +233,9 @@ class Folder extends Node implements \OCP\Files\Folder {
 			throw new \InvalidArgumentException('searching by owner is only allowed in the users home folder');
 		}
 
-		[$caches, $mountByMountPoint] = $this->getCachesAndMountpointsForSearch($limitToHome);
-
 		/** @var QuerySearchHelper $searchHelper */
 		$searchHelper = \OC::$server->get(QuerySearchHelper::class);
+		[$caches, $mountByMountPoint] = $searchHelper->getCachesAndMountPointsForSearch($this->root, $this->path, $limitToHome);
 		$resultsPerCache = $searchHelper->searchInCaches($query, $caches);
 
 		// loop through all results per-cache, constructing the FileInfo object from the CacheEntry and merge them all
@@ -338,24 +305,6 @@ class Folder extends Node implements \OCP\Files\Folder {
 	}
 
 	/**
-	 *
-	 * @return array<array-key, array{id: int, name: string, visibility: int, editable: int, ref_file_id: int, number_files: int}>
-	 */
-	public function getSystemTags(string $mediaType, int $limit = 0, int $offset = 0): array {
-		// Currently query has to have exactly one search condition. If no media type is provided,
-		// we fall back to the presence of a systemtag.
-		if (empty($mediaType)) {
-			$query = $this->queryFromOperator(new SearchComparison(ISearchComparison::COMPARE_LIKE, 'systemtag', '%'), null, $limit, $offset);
-		} else {
-			$query = $this->queryFromOperator(new SearchComparison(ISearchComparison::COMPARE_LIKE, 'mimetype', $mediaType . '/%'), null, $limit, $offset);
-		}
-		[$caches, ] = $this->getCachesAndMountpointsForSearch();
-		/** @var QuerySearchHelper $searchHelper */
-		$searchHelper = \OCP\Server::get(QuerySearchHelper::class);
-		return $searchHelper->findUsedTagsInCaches($query, $caches);
-	}
-
-	/**
 	 * @param int $id
 	 * @return \OC\Files\Node\Node[]
 	 */
diff --git a/lib/private/SystemTag/SystemTagsInFilesDetector.php b/lib/private/SystemTag/SystemTagsInFilesDetector.php
new file mode 100644
index 00000000000..0fcd7e051f6
--- /dev/null
+++ b/lib/private/SystemTag/SystemTagsInFilesDetector.php
@@ -0,0 +1,68 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OC\SystemTag;
+
+use OC\Files\Cache\QuerySearchHelper;
+use OC\Files\Node\Root;
+use OC\Files\Search\SearchComparison;
+use OC\Files\Search\SearchQuery;
+use OCP\Files\Folder;
+use OCP\Files\Search\ISearchComparison;
+
+class SystemTagsInFilesDetector {
+	public function __construct(protected QuerySearchHelper $searchHelper) {
+	}
+
+	public function detectAssignedSystemTagsIn(
+		Folder $folder,
+		string $filteredMediaType = '',
+		int $limit = 0,
+		int $offset = 0
+	): array {
+		// Currently query has to have exactly one search condition. If no media type is provided,
+		// we fall back to the presence of a system tag.
+		if (empty($filteredMediaType)) {
+			$query = new SearchQuery(new SearchComparison(ISearchComparison::COMPARE_LIKE, 'systemtag', '%'), $limit, $offset, []);
+		} else {
+			$query = new SearchQuery(new SearchComparison(ISearchComparison::COMPARE_LIKE, 'mimetype', $filteredMediaType . '/%'), $limit, $offset, []);
+		}
+		[$caches, ] = $this->searchHelper->getCachesAndMountPointsForSearch(
+			$this->getRootFolder($folder),
+			$folder->getPath(),
+		);
+		return $this->searchHelper->findUsedTagsInCaches($query, $caches);
+	}
+
+	protected function getRootFolder(?Folder $folder): Root {
+		if ($folder instanceof Root) {
+			return $folder;
+		} elseif ($folder === null) {
+			throw new \LogicException('Could not climb up to root folder');
+		}
+		return $this->getRootFolder($folder->getParent());
+	}
+}