text: // @flow
  import i18n from "i18next";
  import backend from "i18next-http-backend";
  import { initReactI18next } from "react-i18next";
  
  // Note: Updating the available languages? Make sure to also update the
  // locales array in app/components/LocaleTime.js to enable translation for timestamps.
  export const languageOptions = [
    { label: "English (US)", value: "en_US" },
    { label: "简体中文 (Chinese, Simplified)", value: "zh_CN" },
    { label: "繁體中文 (Chinese, Traditional)", value: "zh_TW" },
    { label: "Deutsch (Deutschland)", value: "de_DE" },
    { label: "Español (España)", value: "es_ES" },
    { label: "Français (France)", value: "fr_FR" },
    { label: "Italiano (Italia)", value: "it_IT" },
    { label: "日本語 (Japanese)", value: "ja_JP" },
    { label: "한국어 (Korean)", value: "ko_KR" },
    { label: "Português (Brazil)", value: "pt_BR" },
    { label: "Português (Portugal)", value: "pt_PT" },
    { label: "Pусский (Россия)", value: "ru_RU" },
  ];
  
  export const languages: string[] = languageOptions.map((i) => i.value);
  
  // Languages are stored in en_US format in the database, however the
  // frontend translation framework (i18next) expects en-US
  const underscoreToDash = (text: string) => text.replace("_", "-");
  const dashToUnderscore = (text: string) => text.replace("-", "_");
  
  export const initI18n = () => {
    const lng = underscoreToDash(
      "DEFAULT_LANGUAGE" in process.env ? process.env.DEFAULT_LANGUAGE : "en_US"
    );
  
    i18n
      .use(backend)
      .use(initReactI18next)
      .init({
        backend: {
          // this must match the path defined in routes. It's the path that the
          // frontend UI code will hit to load missing translations.
          loadPath: (languages: string[], namespaces: string[]) =>
            `/locales/${dashToUnderscore(languages[0])}.json`,
        },
        interpolation: {
          escapeValue: false,
        },
        react: {
          useSuspense: false,
        },
        lng,
        fallbackLng: lng,
        supportedLngs: languages.map(underscoreToDash),
        // Uncomment when debugging translation framework, otherwise it's noisy
        // debug: process.env.NODE_ENV === "development",
        keySeparator: false,
      });
  
    return i18n;
  };
  