cleanup the trash bin tables in the database after a user was deleted

apps/files_trashbin/appinfo/app.php

@@ -3,5 +3,7 @@
 OC::$CLASSPATH['OCA\Files_Trashbin\Hooks'] = 'files_trashbin/lib/hooks.php';
 OC::$CLASSPATH['OCA\Files_Trashbin\Trashbin'] = 'files_trashbin/lib/trash.php';
 
-
+//Listen to delete file signal
 OCP\Util::connectHook('OC_Filesystem', 'delete', "OCA\Files_Trashbin\Hooks", "remove_hook");
+//Listen to delete user signal
+OCP\Util::connectHook('OC_User', 'pre_deleteUser', "OCA\Files_Trashbin\Hooks", "deleteUser_hook");
\ No newline at end of file

apps/files_trashbin/lib/hooks.php

@@ -42,4 +42,18 @@ class Hooks {
 			Trashbin::move2trash($path);
 		}
 	}
+
+	/**
+	 * @brief clean up user specific settings if user gets deleted
+	 * @param array with uid
+	 *
+	 * This function is connected to the pre_deleteUser signal of OC_Users
+	 * to remove the used space for the trash bin stored in the database
+	 */
+	public static function deleteUser_hook($params) {
+		if( \OCP\App::isEnabled('files_trashbin') ) {
+			$uid = $params['uid'];
+			Trashbin::deleteUser($uid);
+			}
+	}
 }

apps/files_trashbin/lib/trash.php

@@ -336,6 +336,22 @@ class Trashbin {
 		return $view->file_exists($target);
 	}
 
+	/**
+	 * @brief deletes used space for trash bin 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_trash` WHERE `user`=?');
+		$result = $query->execute(array($uid));
+		if ($result) {
+			$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_trashsize` WHERE `user`=?');
+			return $query->execute(array($uid));
+		}
+		return false;
+	}
+
 	/**
 	 * clean up the trash bin
 	 * @param max. available disk space for trashbin