MD Settings: Add Hotword (OK Google) section to search_page

chrome/browser/resources/settings/search_page/search_page.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview
  * 'settings-search-page' is the settings page containing search settings.
  */
 Polymer({
   is: 'settings-search-page',
 
+  behaviors: [I18nBehavior],
+
   properties: {
     prefs: Object,
 
     /**
      * List of default search engines available.
      * @private {!Array<!SearchEngine>}
      */
     searchEngines_: {
       type: Array,
-      value: function() { return []; }
+      value: function() {
+        return [];
+      }
     },
+
+    /** @private {!SearchPageHotwordInfo|undefined} */
+    hotwordInfo_: Object,
+
+    /**
+     * This is a local PrefObject used to reflect the enabled state of hotword
+     * search. It is not tied directly to a pref. (There are two prefs
+     * associated with  state and they do not map directly to whether or not
+     * hotword search is actually enabled).
+     * @private {!chrome.settingsPrivate.PrefObject|undefined}
+     */
+    hotwordSearchEnablePref_: Object,
   },
 
   /** @private {?settings.SearchEnginesBrowserProxy} */
   browserProxy_: null,
 
   /** @override */
   created: function() {
     this.browserProxy_ = settings.SearchEnginesBrowserProxyImpl.getInstance();
   },
 
   /** @override */
   ready: function() {
+    // Omnibox search engine
     var updateSearchEngines = function(searchEngines) {
       this.set('searchEngines_', searchEngines.defaults);
     }.bind(this);
     this.browserProxy_.getSearchEnginesList().then(updateSearchEngines);
     cr.addWebUIListener('search-engines-changed', updateSearchEngines);
+
+    // Hotword (OK Google)
+    cr.addWebUIListener(
+        'hotword-info-update', this.hotwordInfoUpdate_.bind(this));
+    this.browserProxy_.getHotwordInfo().then(function(hotwordInfo) {
+      this.hotwordInfoUpdate_(hotwordInfo);
+    }.bind(this));
   },
 
   /** @private */
   onChange_: function() {
     var select = /** @type {!HTMLSelectElement} */ (this.$$('select'));
     var searchEngine = this.searchEngines_[select.selectedIndex];
     this.browserProxy_.setDefaultSearchEngine(searchEngine.modelIndex);
   },
 
   /** @private */
   onDisableExtension_: function() {
     this.fire('refresh-pref', 'default_search_provider.enabled');
   },
 
   /** @private */
   onManageSearchEnginesTap_: function() {
     settings.navigateTo(settings.Route.SEARCH_ENGINES);
   },
+
+  /**
+   * @param {Event} event
+   * @private
+   */
+  onHotwordSearchEnableChange_: function(event) {
+    // Do not set the pref directly, allow Chrome to run the setup app instead.
+    this.browserProxy_.setHotwordSearchEnabled(
+        !!this.hotwordSearchEnablePref_.value);
+  },
+
+  /**
+   * @param {!SearchPageHotwordInfo} hotwordInfo
+   * @private
+   */
+  hotwordInfoUpdate_: function(hotwordInfo) {
+    this.hotwordInfo_ = hotwordInfo;
+    this.hotwordSearchEnablePref_ = {
+      key: 'unused',  // required for PrefObject
+      type: chrome.settingsPrivate.PrefType.BOOLEAN,
+      value: this.hotwordInfo_.enabled,
+    };
+  },
+
+  /**
+   * @return {string}
+   * @private
+   */
+  getHotwordSearchEnableSubLabel_: function() {
+    return this.i18n(
+        this.hotwordInfo_.alwaysOn ? 'searchOkGoogleSubtextAlwaysOn' :
+                                     'searchOkGoogleSubtextNoHardware');
+  },
+
+  /**
+   * @return {boolean}
+   * @private
+   */
+  getShowHotwordSearchRetrain_: function() {
+    return this.hotwordInfo_.enabled && this.hotwordInfo_.alwaysOn;
+  },
+
+  /**
+   * @return {boolean} True if the pref is enabled but hotword is not.
+   * @private
+   */
+  getShowHotwordError_: function() {
+    return this.hotwordInfo_.enabled && !!this.hotwordInfo_.errorMessage;
+  },
+
+  /** @private */
+  onRetrainTap_: function() {
+    // Re-enable hotword search enable; this will trigger the retrain UI.
+    this.browserProxy_.setHotwordSearchEnabled(this.hotwordInfo_.enabled);
+  },
+
+  /** @private */
+  onManageAudioHistoryTap_: function() {
+    window.open(loadTimeData.getString('manageAudioHistoryUrl'));
+  },
+
+  /**
+   * @param {Event} event
+   * @private
+   */
+  doNothing_: function(event) {
+    event.stopPropagation();
+  }
 });