ffrgb / meshviewer

define(['polyglot', 'moment', 'helper'], function (Polyglot, moment, helper) {

  'use strict';

  return function () {

    var router;

    function languageSelect(el) {

      var select = document.createElement('select');

      select.className = 'language-switch';

      select.setAttribute('aria-label', 'Language');

      select.addEventListener('change', setSelectLocale);

      el.appendChild(select);

      // Keep english

      select.innerHTML = '<option>Language</option>';

      for (var i = 0; i < config.supportedLocale.length; i++) {

        select.innerHTML += '<option value="' + config.supportedLocale[i] + '">' + config.supportedLocale[i] + '</option>';

      }

    }

    function setSelectLocale(event) {

      router.fullUrl({ lang: event.target.value }, false, true);

    }

    function setLocale(lang) {

      localStorage.setItem('language', getLocale(lang));

      location.reload();

    }

    function getLocale(input) {

      var language = input || localStorage.getItem('language') || navigator.languages && navigator.languages[0] || navigator.language || navigator.userLanguage;

      var locale = config.supportedLocale[0];

      config.supportedLocale.some(function (item) {

        if (language.indexOf(item) !== -1) {

          locale = item;

          return true;

        }

        return false;

      });

      return locale;

    }

    function setTranslation(json) {

      _.extend(json);

      if (moment.locale(_.locale()) !== _.locale()) {

        moment.defineLocale(_.locale(), {

          longDateFormat: {

            LT: 'HH:mm',

            LTS: 'HH:mm:ss',

            L: 'DD.MM.YYYY',

            LL: 'D. MMMM YYYY',

            LLL: 'D. MMMM YYYY HH:mm',

            LLLL: 'dddd, D. MMMM YYYY HH:mm'

          },

          calendar: json.momentjs.calendar,

          relativeTime: json.momentjs.relativeTime

        });

      }

    }

    function init(r) {

      router = r;

      /** global: _ */

      window._ = new Polyglot({ locale: getLocale(router.getLang()), allowMissing: true });

      helper.getJSON('locale/' + _.locale() + '.json?' + config.cacheBreaker).then(setTranslation);

      document.querySelector('html').setAttribute('lang', _.locale());

    }

    return {

      init: init,

      getLocale: getLocale,

      setLocale: setLocale,

      languageSelect: languageSelect

    };

  };

});