/* global Intl */
import i18n from 'i18next';
import { Meteor } from 'meteor/meteor';
import { Tracker } from 'meteor/tracker';
import { ReactiveVar } from 'meteor/reactive-var';
import backend from 'i18next-http-backend';
import LngDetector from 'i18next-browser-languagedetector';
import { T9n } from 'meteor-accounts-t9n';
import moment from 'moment';
import 'moment/locale/es';
import 'moment/locale/pt';
import 'moment/locale/gl';
import i18nOpts from '../common/i18n';

// Adapted from: https://github.com/appigram/ryfma-boilerplate/blob/44c1eabfb9928b5623afab36a23997969e5beb02/imports/startup/client/i18n.js

const detectorOptions = {
  // order and from where user language should be detected
  order: ['querystring', 'navigator', 'cookie', 'localStorage', 'htmlTag'],

  // keys or params to lookup language from
  lookupQuerystring: 'lng',
  lookupCookie: 'i18next',
  lookupLocalStorage: 'i18nextLng',

  // cache user language on
  caches: ['localStorage', 'cookie'],
  excludeCacheFor: ['cimode'] // languages to not persist (cookie, localStorage)
};

export const i18nReady = new ReactiveVar(false);

i18nOpts.detection = detectorOptions;
i18nOpts.react = {
  useSuspense: false, // was `wait: true` pre-react-i18next-10
  defaultTransParent: 'span'
  // https://react.i18next.com/components/i18next-instance.ht
  /* bindI18n: 'languageChanged loaded',
   bindStore: 'added removed',
   nsMode: 'default' */
};

const sendMissing = true; // Meteor.isDevelopment;
if (sendMissing && Meteor.isDevelopment) {
  i18nOpts.saveMissing = true;
  // Modern signature is (lngs, ns, key, fallbackValue, ...); key/fallback keep
  // the same positions, so we still only need those two.
  i18nOpts.missingKeyHandler = function miss(lngs, ns, key, defaultValue) {
    Meteor.call('utility.saveMissingI18n', key, defaultValue);
  };
}

function setT9(lang) {
  // meteor-accounts-t9n has no Galician build, so use Spanish for gl account
  // error messages (the closest shipped language). See common/i18n.js.
  if (lang === 'gl') {
    T9n.setLanguage('es');
  } else {
    T9n.setLanguage(lang);
  }
}

i18n.use(backend)
  .use(LngDetector)
  .init(i18nOpts, (err, t) => {
    // initialized and ready to
    if (err) {
      console.error(err);
      return;
    }
    console.log(`Language initialized: ${i18n.language}`);

    // document.title = t('AppName');
    // Accounts translation
    // https://github.com/softwarerero/meteor-accounts-t9n
    setT9(i18n.language);
    // console.log(T9n.get('error.accounts.User not found'));
    moment.locale(i18n.language);

    i18nReady.set(true);

    // Cookie consent banner: selaias:cookie-consent (Blaze, dead on Meteor 3)
    // replaced by the React component imports/ui/components/CookieConsent,
    // which reuses the same i18n keys.
  });

Meteor.subscribe('userData'); // lang is there

i18n.on('languageChanged', (lng) => {
  moment.locale(lng);
  // TODO fix this when gl is translated
  setT9(lng);
  Tracker.autorun((computation) => {
    if (Meteor.userId()) {
      // logged
      if (Meteor.user() && (typeof Meteor.user().lang === 'undefined' ||
                            Meteor.user().lang !== lng)
      ) {
        // Set the autodetected/changed lang
        console.log(`Setting the autodetected lang ${lng}, from previous ${Meteor.user().lang}`);
        // console.log(Meteor.user());
        Meteor.call('users.setLang', lng, (error) => {
          if (error) {
            console.error(error);
          }
        });
        computation.stop(); // not need it again til new lang change
      }
    }
  });
});

export default i18n;