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.Element');
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.util.Dom');


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

    this.addLanguagesButton_();

    this.addAudioLangMenu_();

    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_();
    });

    this.eventManager.listen(this.languagesButton_, 'click', () => {
      this.onLanguagesClick_();
    });

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

    this.updateAudioLanguages_();
  }


  /**
   * @private
   */
  addAudioLangMenu_() {
    /** @private {!HTMLElement} */
    this.audioLangMenu_ = shaka.util.Dom.createHTMLElement('div');
    this.audioLangMenu_.classList.add('shaka-audio-languages');
    this.audioLangMenu_.classList.add('shaka-no-propagation');
    this.audioLangMenu_.classList.add('shaka-show-controls-on-mouse-over');
    this.audioLangMenu_.classList.add('shaka-settings-menu');

    /** @private {!HTMLElement} */
    this.backFromLanguageButton_ = shaka.util.Dom.createHTMLElement('button');
    this.backFromLanguageButton_.classList.add('shaka-back-to-overflow-button');
    this.audioLangMenu_.appendChild(this.backFromLanguageButton_);

    const backIcon = shaka.util.Dom.createHTMLElement('i');
    backIcon.classList.add('material-icons');
    backIcon.textContent = shaka.ui.Enums.MaterialDesignIcons.BACK;
    this.backFromLanguageButton_.appendChild(backIcon);

    /** @private {!HTMLElement} */
    this.backFromLanguageSpan_ = shaka.util.Dom.createHTMLElement('span');
    this.backFromLanguageButton_.appendChild(this.backFromLanguageSpan_);

    const controlsContainer = this.controls.getControlsContainer();
    controlsContainer.appendChild(this.audioLangMenu_);
  }


  /**
   * @private
   */
  addLanguagesButton_() {
    /** @private {!HTMLElement} */
    this.languagesButton_ = shaka.util.Dom.createHTMLElement('button');
    this.languagesButton_.classList.add('shaka-language-button');

    const icon = shaka.util.Dom.createHTMLElement('i');
    icon.classList.add('material-icons');
    icon.textContent = shaka.ui.Enums.MaterialDesignIcons.LANGUAGE;
    this.languagesButton_.appendChild(icon);

    const label = shaka.util.Dom.createHTMLElement('label');
    label.classList.add('shaka-overflow-button-label');

    /** @private {!HTMLElement} */
    this.languageNameSpan_ = shaka.util.Dom.createHTMLElement('span');
    this.languageNameSpan_.classList.add('languageSpan');
    label.appendChild(this.languageNameSpan_);

    /** @private {!HTMLElement} */
    this.currentAudioLanguage_ = shaka.util.Dom.createHTMLElement('span');
    this.currentAudioLanguage_.classList.add('shaka-current-selection-span');
    const language = this.player.getConfiguration().preferredAudioLanguage;
    this.currentAudioLanguage_.textContent =
      shaka.ui.LanguageUtils.getLanguageName(language, this.localization);
    label.appendChild(this.currentAudioLanguage_);

    this.languagesButton_.appendChild(label);

    this.parent.appendChild(this.languagesButton_);
  }

  /** @private */
  onLanguagesClick_() {
    this.controls.dispatchEvent(new shaka.util.FakeEvent('submenuopen'));
    shaka.ui.Utils.setDisplay(this.audioLangMenu_, true);
    // Focus on the currently selected language button.
    shaka.ui.Utils.focusOnTheChosenItem(this.audioLangMenu_);
  }

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

    shaka.ui.LanguageUtils.updateLanguages(tracks, this.audioLangMenu_,
      languages,
      this.onAudioLanguageSelected_.bind(this), /* updateChosen */ true,
      this.currentAudioLanguage_,
      this.localization);
    shaka.ui.Utils.focusOnTheChosenItem(this.audioLangMenu_);

    // TODO: document this event
    this.controls.dispatchEvent(
        new shaka.util.FakeEvent('languageselectionupdated'));
  }

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

  /**
   * @param {string} language
   * @private
   */
  onAudioLanguageSelected_(language) {
    this.player.selectAudioLanguage(language);
  }


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

    this.backFromLanguageButton_.setAttribute(shaka.ui.Constants.ARIA_LABEL,
        this.localization.resolve(LocIds.BACK));
    this.languagesButton_.setAttribute(shaka.ui.Constants.ARIA_LABEL,
        this.localization.resolve(LocIds.LANGUAGE));
    this.languageNameSpan_.textContent =
        this.localization.resolve(LocIds.LANGUAGE);
    this.backFromLanguageSpan_.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());