import timeago from 'timeago.js';
import esTA from '../../../../node_modules/timeago.js/locales/es';
import has from 'lodash/has';
import get from 'lodash/get';

/**
 * Default locales, this should be overriden by config file
 */

class i18n {
  constructor (translations) {

    /**
     * Register locales
     */

    this.locales = {'en': 'en', 'es': 'es'};
    timeago.register('es_ES', esTA);
    this.timeagoInstance = new timeago();

    /**
     * Load translations
     */
    let trans = translations || {en: {}};

    try {
      const locale = localStorage.getItem('locale') || navigator.language;
      localStorage.setItem('locale', locale);
      const lang = this.locales[locale.split('-')[0]] || 'en';
      this.translations = trans[lang];
    } catch (err) {
      this.translations = trans['en'];
    }

    this.setLocale = (locale) => {
      try {
        localStorage.setItem('locale', locale);
      } catch (err) {
        console.error(err);
      }
    };

    this.getLocale = () => (
      localStorage.getItem('locale') || navigator.locale || 'en-US'
    );

      /**
       * Expose the translation function
       *
       * it takes a string with the translation key and returns
       * the translation value or the key itself if not found
       * it works with nested translations (my.page.title)
       *
       * any extra parameters are optional and replace a variable marked by {0}, {1}, etc in the translation.
       */

    this.t = (key, ...replacements) => {
      if (has(this.translations, key)) {
        let translation = get(this.translations, key);

        // replace any {n} with the arguments passed to this method
        replacements.forEach((str, i) => {
          translation = translation.replace(new RegExp(`\\{${i}\\}`, 'g'), str);
        });
        return translation;
      } else {
        console.warn(`${key} language key not set`);
        return key;
      }
    };

    this.timeago = (time) => {
      return this.timeagoInstance.format(new Date(time));
    };
  }
}

export default i18n;