Removes the dependency between AudioManager and PluginManager.

Now AudioManager can listen the audio without hotword recognition.
The mean volume level would be useful to the speech UI.

BUG=313904
R=xiyuan@chromium.org
TEST=manually

Review URL: https://codereview.chromium.org/92863004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238753 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 89 insertions, 74 deletions

diff --git a/chrome/browser/resources/app_list/audio_manager.js b/chrome/browser/resources/app_list/audio_manager.js
index 4f2a301..9862ac4 100644
--- a/chrome/browser/resources/app_list/audio_manager.js
+++ b/chrome/browser/resources/app_list/audio_manager.js
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 /**
- * @fileoverview The manager of audio streams and interaction with the plugin.
+ * @fileoverview The manager of audio streams.
  */
 
 cr.define('speech', function() {
@@ -15,38 +15,21 @@ cr.define('speech', function() {
    * @enum {number}
    */
   var AudioState = {
-    UNINITIALIZED: 0,
-    READY: 1,
-    RECOGNIZING: 2
+    STOPPED: 0,
+    LISTENING: 1
   };
 
   /**
    * @constructor
+   * @extends {cr.EventTarget}
    */
-  function AudioManager(onReady, onRecognizing, onRecognized) {
-    this.state = AudioState.UNINITIALIZED;
-    if (!speech.isPluginAvailable())
-      return;
-    this.onReady_ = onReady;
-    this.onRecognizing_ = onRecognizing;
-    this.pluginManager_ = new speech.PluginManager(
-        this.onPluginReady_.bind(this), onRecognized);
+  function AudioManager() {
     this.audioContext_ = new window.webkitAudioContext();
     this.audioProc_ = null;
-    this.pluginManager_.scheduleInitialize(
-        this.audioContext_.sampleRate,
-        'chrome://app-list/okgoogle_hotword.config');
+    this.state = AudioState.STOPPED;
   };
 
-  /**
-   * Called when the plugin is ready.
-   *
-   * @private
-   */
-  AudioManager.prototype.onPluginReady_ = function() {
-    this.state = AudioState.READY;
-    this.onReady_();
-  };
+  AudioManager.prototype.__proto__ = cr.EventTarget.prototype;
 
   /**
    * Called when the audio data arrives.
@@ -59,7 +42,9 @@ cr.define('speech', function() {
     var intData = new Int16Array(data.length);
     for (var i = 0; i < data.length; ++i)
       intData[i] = Math.round(data[i] * 32767);
-    this.pluginManager_.sendAudioData(intData.buffer);
+    var event = new Event('audio');
+    event.data = intData;
+    this.dispatchEvent(event);
   };
 
   /**
@@ -76,27 +61,27 @@ cr.define('speech', function() {
 
     audioIn.connect(this.audioProc_);
     this.audioProc_.connect(this.audioContext_.destination);
-    this.state = AudioState.RECOGNIZING;
-    this.onRecognizing_();
+    this.state = AudioState.LISTENING;
   };
 
   /**
-   * Starts the audio recognition with the plugin.
+   * Returns the sampling rate of the current audio context.
+   * @return {number} The sampling rate.
+   */
+  AudioManager.prototype.getSampleRate = function() {
+    return this.audioContext_.sampleRate;
+  };
+
+  /**
+   * Starts the audio processing.
    */
   AudioManager.prototype.start = function() {
-    // Not yet initialized.
-    if (this.state != AudioState.READY)
-      return;
-    if (this.pluginManager_.state < speech.PluginState.READY)
+    if (this.state == AudioState.LISTENING)
       return;
 
-    if (this.pluginManager_.state == speech.PluginState.READY)
-      this.pluginManager_.startRecognizer();
-
     if (this.audioProc_) {
       this.audioProc_.connect(this.audioContext_.destination);
-      this.state = AudioState.RECOGNIZING;
-      this.onRecognizing_();
+      this.state = AudioState.LISTENING;
       return;
     }
 
@@ -107,17 +92,17 @@ cr.define('speech', function() {
   };
 
   /**
-   * Stops the audio recognition.
+   * Stops the audio processing.
    */
   AudioManager.prototype.stop = function() {
-    if (this.state <= AudioState.READY)
+    if (this.state != AudioState.LISTENING)
       return;
     this.audioProc_.disconnect();
-    this.pluginManager_.stopRecognizer();
-    this.state = AudioState.READY;
+    this.state = AudioState.STOPPED;
   };
 
   return {
-    AudioManager: AudioManager
+    AudioManager: AudioManager,
+    AudioState: AudioState
   };
 });
diff --git a/chrome/browser/resources/app_list/plugin_manager.js b/chrome/browser/resources/app_list/plugin_manager.js
index 0bce749..fb8a604 100644
--- a/chrome/browser/resources/app_list/plugin_manager.js
+++ b/chrome/browser/resources/app_list/plugin_manager.js
@@ -75,7 +75,7 @@ cr.define('speech', function() {
 
     if (messageEvent.data == 'audio') {
       if (this.state < PluginState.READY)
-        this.onReady_();
+        this.onReady_(this);
       this.state = PluginState.RECOGNIZING;
     } else if (messageEvent.data == 'stopped') {
       this.state = PluginState.READY;
@@ -133,23 +133,26 @@ cr.define('speech', function() {
    * Asks the plugin to start recognizing the hotword.
    */
   PluginManager.prototype.startRecognizer = function() {
-    $('recognizer').postMessage(pluginCommands.START_RECOGNIZING);
+    if (this.state == PluginState.READY)
+      $('recognizer').postMessage(pluginCommands.START_RECOGNIZING);
   };
 
   /**
    * Asks the plugin to stop recognizing the hotword.
    */
   PluginManager.prototype.stopRecognizer = function() {
-    $('recognizer').postMessage(pluginCommands.STOP_RECOGNIZING);
+    if (this.state == PluginState.RECOGNIZING)
+      $('recognizer').postMessage(pluginCommands.STOP_RECOGNIZING);
   };
 
   /**
    * Sends the actual audio wave data.
    *
-   * @param {ArrayBuffer} data The audio data to be recognized.
+   * @param {cr.event.Event} event The event for the audio data.
    */
-  PluginManager.prototype.sendAudioData = function(data) {
-    $('recognizer').postMessage(data);
+  PluginManager.prototype.sendAudioData = function(event) {
+    if (this.state == PluginState.RECOGNIZING)
+      $('recognizer').postMessage(event.data.buffer);
   };
 
   return {
diff --git a/chrome/browser/resources/app_list/speech_manager.js b/chrome/browser/resources/app_list/speech_manager.js
index 08284be..c55eab7 100644
--- a/chrome/browser/resources/app_list/speech_manager.js
+++ b/chrome/browser/resources/app_list/speech_manager.js
@@ -19,7 +19,6 @@ cr.define('speech', function() {
    * @enum {string}
    */
   var SpeechState = {
-    UNINITIALIZED: 'UNINITIALIZED',
     READY: 'READY',
     HOTWORD_RECOGNIZING: 'HOTWORD_RECOGNIZING',
     RECOGNIZING: 'RECOGNIZING'
@@ -29,12 +28,18 @@ cr.define('speech', function() {
    * @constructor
    */
   function SpeechManager() {
-    this.audioManager_ = new speech.AudioManager(
-        this.onHotwordRecognizerReady_.bind(this),
-        this.onHotwordRecognizing_.bind(this),
-        this.onHotwordRecognized_.bind(this));
+    this.audioManager_ = new speech.AudioManager();
+    this.audioManager_.addEventListener('audio', this.onAudioLevel_.bind(this));
+    if (speech.isPluginAvailable()) {
+      var pluginManager = new speech.PluginManager(
+          this.onHotwordRecognizerReady_.bind(this),
+          this.onHotwordRecognized_.bind(this));
+      pluginManager.scheduleInitialize(
+          this.audioManager_.getSampleRate(),
+          'chrome://app-list/okgoogle_hotword.config');
+    }
     this.speechRecognitionManager_ = new speech.SpeechRecognitionManager(this);
-    this.setState_(SpeechState.UNINITIALIZED);
+    this.setState_(SpeechState.READY);
   }
 
   /**
@@ -49,11 +54,32 @@ cr.define('speech', function() {
   };
 
   /**
+   * Called with the mean audio level when audio data arrives.
+   *
+   * @param {cr.event.Event} event The event object for the audio data.
+   * @private
+   */
+  SpeechManager.prototype.onAudioLevel_ = function(event) {
+    var data = event.data;
+    var level = 0;
+    for (var i = 0; i < data.length; ++i)
+      level += Math.abs(data[i]);
+    level /= data.length;
+    // TODO(mukai): use the result to make the audio feedback during the speech
+    // recognition.
+  };
+
+  /**
    * Called when the hotword recognizer is ready.
    *
+   * @param {PluginManager} pluginManager The hotword plugin manager which gets
+   *   ready.
    * @private
    */
-  SpeechManager.prototype.onHotwordRecognizerReady_ = function() {
+  SpeechManager.prototype.onHotwordRecognizerReady_ = function(pluginManager) {
+    this.pluginManager_ = pluginManager;
+    this.audioManager_.addEventListener(
+        'audio', pluginManager.sendAudioData.bind(pluginManager));
     this.setState_(SpeechState.READY);
   };
 
@@ -66,21 +92,12 @@ cr.define('speech', function() {
   SpeechManager.prototype.onHotwordRecognized_ = function(confidence) {
     if (this.state != SpeechState.HOTWORD_RECOGNIZING)
       return;
-    this.audioManager_.stop();
     this.setState_(SpeechState.READY);
+    this.pluginManager_.stopRecognizer();
     this.speechRecognitionManager_.start();
   };
 
   /**
-   * Called when the hotword recognition has started.
-   *
-   * @private
-   */
-  SpeechManager.prototype.onHotwordRecognizing_ = function() {
-    this.setState_(SpeechState.HOTWORD_RECOGNIZING);
-  };
-
-  /**
    * Called when the speech recognition has happened.
    *
    * @param {string} result The speech recognition result.
@@ -108,7 +125,13 @@ cr.define('speech', function() {
    */
   SpeechManager.prototype.onSpeechRecognitionEnded = function() {
     // Restarts the hotword recognition.
-    this.audioManager_.start();
+    if (this.pluginManager_) {
+      this.pluginManager_.startRecognizer();
+      this.audioManager_.start();
+      this.setState_(SpeechState.HOTWORD_RECOGNIZING);
+    } else {
+      this.audioManager_.stop();
+    }
     chrome.send('setSpeechRecognitionState', [false]);
   };
 
@@ -118,33 +141,32 @@ cr.define('speech', function() {
    * @param {SpeechRecognitionError} e The error object.
    */
   SpeechManager.prototype.onSpeechRecognitionError = function(e) {
-    this.setState_(SpeechState.UNINITIALIZED);
+    this.setState_(SpeechState.READY);
   };
 
   /**
    * Starts the speech recognition session.
    */
   SpeechManager.prototype.start = function() {
-    if (this.state == SpeechState.UNINITIALIZED) {
-      console.warn('hotword recognizer is not yet initialized');
+    if (!this.pluginManager_)
       return;
-    }
 
     if (this.state != SpeechState.READY) {
       console.warn('Already in recognition state...');
       return;
     }
 
+    this.pluginManager_.startRecognizer();
     this.audioManager_.start();
+    this.setState_(SpeechState.HOTWORD_RECOGNIZING);
   };
 
   /**
    * Stops the speech recognition session.
    */
   SpeechManager.prototype.stop = function() {
-    if (this.state == SpeechState.UNINITIALIZED)
-      return;
-
+    if (this.pluginManager_)
+      this.pluginManager_.stopRecognizer();
     this.audioManager_.stop();
     this.speechRecognitionManager_.stop();
     this.setState_(SpeechState.READY);
@@ -155,9 +177,13 @@ cr.define('speech', function() {
    */
   SpeechManager.prototype.toggleSpeechRecognition = function() {
     if (this.state == SpeechState.RECOGNIZING) {
+      this.audioManager_.stop();
       this.speechRecognitionManager_.stop();
     } else {
-      this.audioManager_.stop();
+      if (this.pluginManager_)
+        this.pluginManager_.stopRecognizer();
+      if (this.audioManager_.state == speech.AudioState.STOPPED)
+        this.audioManager_.start();
       this.speechRecognitionManager_.start();
     }
   };
diff --git a/chrome/browser/resources/app_list/start_page.html b/chrome/browser/resources/app_list/start_page.html
index 47a9167..2ff0961 100644
--- a/chrome/browser/resources/app_list/start_page.html
+++ b/chrome/browser/resources/app_list/start_page.html
@@ -5,6 +5,7 @@
   <link rel="stylesheet" href="chrome://app-list/start_page.css">
   <script src="chrome://resources/js/load_time_data.js"></script>
   <script src="chrome://resources/js/cr.js"></script>
+  <script src="chrome://resources/js/cr/event_target.js"></script>
   <script src="chrome://resources/js/cr/ui.js"></script>
   <script src="chrome://resources/js/util.js"></script>
   <script src="chrome://app-list/strings.js"></script>