6 files changed, 72 insertions, 4 deletions

diff --git a/apps/files_versions/lib/Capabilities.php b/apps/files_versions/lib/Capabilities.php
index 031cabb83ec..6524943690a 100644
--- a/apps/files_versions/lib/Capabilities.php
+++ b/apps/files_versions/lib/Capabilities.php
@@ -46,12 +46,13 @@ class Capabilities implements ICapability {
 	 * @return array
 	 */
 	public function getCapabilities() {
-		$groupFolderOrS3VersioningInstalled = $this->appManager->isInstalled('groupfolders') || !$this->appManager->isInstalled('groupfolders');
+		$groupFolderOrS3VersioningInstalled = $this->appManager->isInstalled('groupfolders') || $this->appManager->isInstalled('groupfolders');
 
 		return [
 			'files' => [
 				'versioning' => true,
 				'version_labeling' => !$groupFolderOrS3VersioningInstalled && $this->config->getSystemValueBool('enable_version_labeling', true),
+				'version_deletion' => !$groupFolderOrS3VersioningInstalled && $this->config->getSystemValueBool('enable_version_deletion', true),
 			]
 		];
 	}
diff --git a/apps/files_versions/lib/Sabre/VersionFile.php b/apps/files_versions/lib/Sabre/VersionFile.php
index 9018f75703d..12590fe9efd 100644
--- a/apps/files_versions/lib/Sabre/VersionFile.php
+++ b/apps/files_versions/lib/Sabre/VersionFile.php
@@ -26,6 +26,7 @@ declare(strict_types=1);
  */
 namespace OCA\Files_Versions\Sabre;
 
+use OCA\Files_Versions\Versions\IDeletableVersionBackend;
 use OCA\Files_Versions\Versions\INameableVersion;
 use OCA\Files_Versions\Versions\INameableVersionBackend;
 use OCA\Files_Versions\Versions\IVersion;
@@ -72,8 +73,11 @@ class VersionFile implements IFile {
 	}
 
 	public function delete() {
-		// TODO: implement version deletion
-		throw new Forbidden();
+		if ($this->versionManager instanceof IDeletableVersionBackend) {
+			$this->versionManager->deleteVersion($this->version);
+		} else {
+			throw new Forbidden();
+		}
 	}
 
 	public function getName(): string {
diff --git a/apps/files_versions/lib/Storage.php b/apps/files_versions/lib/Storage.php
index 024e1debc92..2f56397ebb8 100644
--- a/apps/files_versions/lib/Storage.php
+++ b/apps/files_versions/lib/Storage.php
@@ -291,6 +291,17 @@ class Storage {
 	}
 
 	/**
+	 * Delete a version of a file
+	 */
+	public static function deleteRevision(string $path, int $revision): void {
+		[$uid, $filename] = self::getUidAndFilename($path);
+		$view = new View('/' . $uid . '/files_versions');
+		\OC_Hook::emit('\OCP\Versions', 'preDelete', ['path' => $path . $revision, 'trigger' => self::DELETE_TRIGGER_MASTER_REMOVED]);
+		self::deleteVersion($view, $filename . '.v' . $revision);
+		\OC_Hook::emit('\OCP\Versions', 'delete', ['path' => $path . $revision, 'trigger' => self::DELETE_TRIGGER_MASTER_REMOVED]);
+	}
+
+	/**
 	 * Rename or copy versions of a file of the given paths
 	 *
 	 * @param string $sourcePath source path of the file to move, relative to
diff --git a/apps/files_versions/lib/Versions/IDeletableVersionBackend.php b/apps/files_versions/lib/Versions/IDeletableVersionBackend.php
new file mode 100644
index 00000000000..abb43d09d90
--- /dev/null
+++ b/apps/files_versions/lib/Versions/IDeletableVersionBackend.php
@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2022 Louis Chmn <louis@chmn.me>
+ *
+ * @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\Files_Versions\Versions;
+
+/**
+ * @since 26.0.0
+ */
+interface IDeletableVersionBackend {
+	/**
+	 * Delete a version.
+	 *
+	 * @since 26.0.0
+	 */
+	public function deleteVersion(IVersion $version): void;
+}
diff --git a/apps/files_versions/lib/Versions/LegacyVersionsBackend.php b/apps/files_versions/lib/Versions/LegacyVersionsBackend.php
index 90c7cb930d5..d5ca4d2a11c 100644
--- a/apps/files_versions/lib/Versions/LegacyVersionsBackend.php
+++ b/apps/files_versions/lib/Versions/LegacyVersionsBackend.php
@@ -187,4 +187,13 @@ class LegacyVersionsBackend implements IVersionBackend, INameableVersionBackend,
 		$versionEntity->setLabel($label ?? '');
 		$this->versionsMapper->update($versionEntity);
 	}
+
+	public function deleteVersion(IVersion $version): void {
+		Storage::deleteRevision($version->getVersionPath(), $version->getRevisionId());
+		$versionEntity = $this->versionsMapper->findVersionForFileId(
+			$version->getSourceFile()->getId(),
+			$version->getTimestamp(),
+		);
+		$this->versionsMapper->delete($versionEntity);
+	}
 }
diff --git a/apps/files_versions/lib/Versions/VersionManager.php b/apps/files_versions/lib/Versions/VersionManager.php
index 4787de7fdac..bfae0937df8 100644
--- a/apps/files_versions/lib/Versions/VersionManager.php
+++ b/apps/files_versions/lib/Versions/VersionManager.php
@@ -30,7 +30,7 @@ use OCP\Files\FileInfo;
 use OCP\Files\Storage\IStorage;
 use OCP\IUser;
 
-class VersionManager implements IVersionManager, INameableVersionBackend {
+class VersionManager implements IVersionManager, INameableVersionBackend, IDeletableVersionBackend {
 	/** @var (IVersionBackend[])[] */
 	private $backends = [];
 
@@ -117,4 +117,11 @@ class VersionManager implements IVersionManager, INameableVersionBackend {
 			$backend->setVersionLabel($version, $label);
 		}
 	}
+
+	public function deleteVersion(IVersion $version): void {
+		$backend = $this->getBackendForStorage($version->getSourceFile()->getStorage());
+		if ($backend instanceof IDeletableVersionBackend) {
+			$backend->deleteVersion($version);
+		}
+	}
 }