(function() {
  'use strict';

  // Global I18n registry that stores and serves translations.
  // Each translation must have a unique ID.
  window.I18n = (function() {

    var translations = {};

    function addTranslation(id, translation) {
      translations[id] = translation;
    }

    function addManyTranslations(manyTranslations) {
      Object.keys(manyTranslations).forEach(function(key) {
        addTranslation(key, manyTranslations[key]);
      });
    }

    function getTranslation(id) {
      if (!translations[id]) {
        return '(translation missing for »' + id + '«)';
      }
      return translations[id];
    }

    // public API
    return {
      add: addTranslation,
      addMany: addManyTranslations,
      get: getTranslation,
    };
  })();
})();