remove used space for versions from db is a user was deleted

apps/files_versions/appinfo/app.php

@@ -12,3 +12,5 @@ OCP\Util::connectHook('OC_Filesystem', 'write', "OCA\Files_Versions\Hooks", "wri
 // Listen to delete and rename signals
 OCP\Util::connectHook('OC_Filesystem', 'post_delete', "OCA\Files_Versions\Hooks", "remove_hook");
 OCP\Util::connectHook('OC_Filesystem', 'rename', "OCA\Files_Versions\Hooks", "rename_hook");
+//Listen to delete user signal
+OCP\Util::connectHook('OC_User', 'pre_deleteUser', "OCA\Files_Versions\Hooks", "deleteUser_hook");

apps/files_versions/lib/hooks.php

@@ -63,4 +63,18 @@ class Hooks {
 		}
 	}
 
+	/**
+	 * @brief clean up user specific settings if user gets deleted
+	 * @param array with uid
+	 *
+	 * This function is connected to the pre_deleteUser signal of OC_Users
+	 * to remove the used space for versions stored in the database
+	 */
+	public static function deleteUser_hook($params) {
+		if(\OCP\Config::getSystemValue('files_versions', Storage::DEFAULTENABLED)=='true') {
+			$uid = $params['uid'];
+			Storage::deleteUser($uid);
+			}
+	}
+
 }

apps/files_versions/lib/versions.php

@@ -279,6 +279,18 @@ class Storage {
 
 	}
 
+
+	/**
+	 * @brief deletes used space for files versions in db if user was deleted
+	 *
+	 * @param type $uid id of deleted user
+	 * @return result of db delete operation
+	 */
+	public static function deleteUser($uid) {
+		$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_versions` WHERE `user`=?');
+		return $query->execute(array($uid));
+	}
+
 	/**
 	 * @brief get the size of all stored versions from a given user
 	 * @param $uid id from the user