code: private String getUniqueZipFileNameInFolder(ArrayList<String> names, String fileName)
              throws IOException, InterruptedException {
  
          String result = fileName + "_Report.zip";
  
          int index = 0;
  
          while (names.indexOf(result) > -1) {
              result = fileName + "_" + (++index) + "_Report.zip";
          }
  
          return result;
      }
docs: /*
  if we have a directory with file name "file.zip" we will return "file_1.zip"