import colors from 'colors/safe';
import * as i18n from 'i18n';
import * as osLocale from 'os-locale';
import * as path from 'path';

type Maybe<T> = false | 0 | undefined | null | T;

enum LocalType {
  Specified = 'specified',
  Detected = 'detected',
}

enum SupportedLanguage {
  En = 'en',
  Pt = 'pt',
  Fr = 'fr',
  Es = 'es',
}

const DEFAULT_LANGUAGE = SupportedLanguage.En;

const i18nEmbark = { __: null };

i18n.configure({
  directory: path.join(__dirname, '../', 'locales'),
  locales: Object.values(SupportedLanguage),
  register: i18nEmbark,
  syncFiles: false,
  updateFiles: false,
});

const isSupported = (locale: string) => {
  return (Object.values(SupportedLanguage) as string[]).includes(locale);
};

export const setOrDetectLocale = (locale: Maybe<string>) => {
  let how = LocalType.Specified;
  if (!locale) {
    how = LocalType.Detected;
    locale = osLocale.sync();
  }
  locale = locale.substr(0, 2);
  if (!isSupported(locale)) {
    console.warn(colors.yellow(`===== locale ${locale} ${how} but not supported, default: en =====`));
    return;
  }
  i18n.setLocale(locale);
};

i18n.setLocale(DEFAULT_LANGUAGE);

export const __ = (i18nEmbark.__ as unknown) as i18nAPI["__"];