Source: ui/audio_language_selection.js

/**
 * @license
 * Copyright 2016 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


goog.provide('shaka.ui.AudioLanguageSelection');

goog.require('shaka.ui.Enums');
goog.require('shaka.ui.LanguageUtils');
goog.require('shaka.ui.Locales');
goog.require('shaka.ui.Localization');
goog.require('shaka.ui.OverflowMenu');
goog.require('shaka.ui.SettingsMenu');

/**
 * @extends {shaka.ui.SettingsMenu}
 * @final
 * @export
 */
shaka.ui.AudioLanguageSelection = class extends shaka.ui.SettingsMenu {
  /**
   * @param {!HTMLElement} parent
   * @param {!shaka.ui.Controls} controls
   */
  constructor(parent, controls) {
    super(parent, controls, shaka.ui.Enums.MaterialDesignIcons.LANGUAGE);

    this.button.classList.add('shaka-language-button');
    this.menu.classList.add('shaka-audio-languages');

    this.eventManager.listen(
        this.localization, shaka.ui.Localization.LOCALE_UPDATED, () => {
          this.updateLocalizedStrings_();
        });

    this.eventManager.listen(
        this.localization, shaka.ui.Localization.LOCALE_CHANGED, () => {
          this.updateLocalizedStrings_();
        });


    this.eventManager.listen(this.player, 'trackschanged', () => {
      this.onTracksChanged_();
    });

    this.eventManager.listen(this.player, 'variantchanged', () => {
      this.updateAudioLanguages_();
    });

    // Set up all the strings in the user's preferred language.
    this.updateLocalizedStrings_();

    this.updateAudioLanguages_();
  }


  /** @private */
  updateAudioLanguages_() {
    const tracks = this.player.getVariantTracks();

    shaka.ui.LanguageUtils.updateTracks(tracks, this.menu,
        (track) => this.onAudioTrackSelected_(track),
        /* updateChosen */ true, this.currentSelection, this.localization,
        this.controls.getConfig().trackLabelFormat);
    shaka.ui.Utils.focusOnTheChosenItem(this.menu);

    this.controls.dispatchEvent(
        new shaka.util.FakeEvent('languageselectionupdated'));
  }

  /** @private */
  onTracksChanged_() {
    const hasVariants = this.player.getVariantTracks().length > 0;
    shaka.ui.Utils.setDisplay(this.button, hasVariants);
    this.updateAudioLanguages_();
  }

  /**
   * @param {!shaka.extern.Track} track
   * @private
   */
  onAudioTrackSelected_(track) {
    this.player.selectAudioLanguage(track.language, track.roles[0]);
  }


  /**
   * @private
   */
  updateLocalizedStrings_() {
    const LocIds = shaka.ui.Locales.Ids;

    this.backButton.setAttribute(shaka.ui.Constants.ARIA_LABEL,
        this.localization.resolve(LocIds.BACK));
    this.button.setAttribute(shaka.ui.Constants.ARIA_LABEL,
        this.localization.resolve(LocIds.LANGUAGE));
    this.nameSpan.textContent =
        this.localization.resolve(LocIds.LANGUAGE);
    this.backSpan.textContent =
        this.localization.resolve(LocIds.LANGUAGE);
  }
};


/**
 * @implements {shaka.extern.IUIElement.Factory}
 * @final
 */
shaka.ui.AudioLanguageSelection.Factory = class {
  /** @override */
  create(rootElement, controls) {
    return new shaka.ui.AudioLanguageSelection(rootElement, controls);
  }
};

shaka.ui.OverflowMenu.registerElement(
    'language', new shaka.ui.AudioLanguageSelection.Factory());