@gramio/i18n/dist/index.js

i18n plugin for GramIO with type-safety

import { FormattableString } from 'gramio';

function buildLanguage(languageRaw) {
  const texts = {};
  function recursiveAdd(textsRaw, prefix = "") {
    for (const [key, value] of Object.entries(textsRaw)) {
      const newPrefix = `${prefix}${key}`;
      if (typeof value === "object" && !(value instanceof FormattableString)) {
        recursiveAdd(value, `${newPrefix}.`);
      } else {
        texts[newPrefix] = value;
      }
    }
  }
  recursiveAdd(languageRaw);
  return texts;
}
function buildT(languages, primaryLanguage) {
  const languagesTexts = {};
  for (const [language, texts] of Object.entries(languages)) {
    languagesTexts[language] = buildLanguage(texts);
  }
  return function t(language, key, ...args) {
    const fallbackItem = languagesTexts[primaryLanguage][key];
    const item = languagesTexts[language] ? languagesTexts[language][key] ?? fallbackItem : fallbackItem;
    if (typeof item === "function") return item(...args);
    return item;
  };
}

function pluralizeEnglish(n, one, many) {
  return n === 1 ? one : many;
}

function pluralizeRussian(count, one, few, many) {
  const mod10 = count % 10;
  const mod100 = count % 100;
  if (mod10 === 1 && mod100 !== 11) return one;
  if (mod10 >= 2 && mod10 <= 4 && (mod100 < 10 || mod100 >= 20)) return few;
  return many;
}

function defineI18n({ languages, primaryLanguage }) {
  const t = buildT(languages, primaryLanguage);
  return {
    t,
    languages: Object.keys(languages),
    primaryLanguage,
    buildT: (language) => {
      return (key, ...args) => t(language, key, ...args);
    },
    /**
     * Generate a `{ languageCode: description }` record for all non-primary languages.
     * Designed for use with `CommandMeta.locales` in `syncCommands()`.
     *
     * Only includes languages where the key resolves to a plain string (no args).
     *
     * @example
     * ```ts
     * bot.command("help", {
     *     description: i18n.t("en", "cmd.help"),
     *     locales: i18n.localesFor("cmd.help"),
     * }, (ctx) => ctx.send("Help"));
     * ```
     */
    localesFor(key, ...args) {
      const result = {};
      for (const lang of Object.keys(languages)) {
        if (lang === primaryLanguage) continue;
        const value = t(lang, key, ...args);
        if (value != null) {
          result[lang] = String(value);
        }
      }
      return result;
    },
    _: {
      languages,
      primaryLanguage
    }
    // plugin: () => {},
  };
}

export { defineI18n, pluralizeEnglish, pluralizeRussian };