code: protected function getMessageFilePath($language)
      {
          $messageFile = Yii::getAlias($this->basePath) . '/' . $language . '/' . $this->catalog;
          if ($this->useMoFile) {
              $messageFile .= self::MO_FILE_EXT;
          } else {
              $messageFile .= self::PO_FILE_EXT;
          }
  
          return $messageFile;
      }
docs: Returns message file path for the specified language and category.
  
  @param string $language the target language
  @return string path to message file