class FileUri

class FileUri extends ProcessPluginBase {

  /**
   * {@inheritdoc}
   */
  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {

    // If we're stubbing a file entity, return a uri of NULL so it will get
    // stubbed by the general process.
    if ($row
      ->isStub()) {
      return NULL;
    }
    [
      $filepath,
      $file_directory_path,
      $temp_directory_path,
      $is_public,
    ] = $value;

    // Specific handling using $temp_directory_path for temporary files.
    if (str_starts_with($filepath, $temp_directory_path)) {
      $uri = preg_replace('/^' . preg_quote($temp_directory_path, '/') . '/', '', $filepath);
      return 'temporary://' . ltrim($uri, '/');
    }

    // Strip the files path from the uri instead of using basename
    // so any additional folders in the path are preserved.
    $uri = preg_replace('/^' . preg_quote($file_directory_path, '/') . '/', '', $filepath);
    return ($is_public ? 'public' : 'private') . '://' . ltrim($uri, '/');
  }

}