WmAutoUpdate.Updater.assertPreviousUpdate C# (CSharp) Method

        private void assertPreviousUpdate()
        {
            string backupDir = appPath + "\\" + BACKUP_FOLDER_NAME;
              string updateDir = appPath + "\\" + UPDATE_FOLDER_NAME;

              if (File.Exists(updateFilePath))
            this.removeFile(updateFilePath);
              if (Directory.Exists(updateDir))
            Directory.Delete(updateDir, true);

              if (File.Exists(backupDir + "\\" + "success"))
            Directory.Delete(backupDir, true);
              else
              {
            if (Directory.Exists(backupDir))
            {
            foreach (string f in Directory.GetFiles(backupDir))
            {
              File.Move(f, appPath + "\\" + getFilenameFromPath(f));
            }
            Directory.Delete(backupDir, true);
            }
              }
        }