Introducing the basic functionality to the speech input experimental API.

chrome/browser/extensions/speech_input/extension_speech_input_manager.h

+// Copyright (c) 2011 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.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_SPEECH_INPUT_EXTENSION_SPEECH_INPUT_MANAGER_H_
+#define CHROME_BROWSER_EXTENSIONS_SPEECH_INPUT_EXTENSION_SPEECH_INPUT_MANAGER_H_
+#pragma once
+
+#include "base/memory/ref_counted.h"
+#include "base/synchronization/lock.h"
+#include "content/browser/speech/speech_recognizer.h"
+#include "content/common/notification_observer.h"
+#include "content/common/notification_registrar.h"
+#include "content/common/speech_input_result.h"
+#include <string>
+
+class Extension;
+class NotificationDetails;
+class NotificationSource;
+class Profile;
+
+namespace net {
+class URLRequestContextGetter;
+}
+
+// Used for API tests. All methods run on the IO thread.
+class ExtensionSpeechInterface {
+ public:
+  ExtensionSpeechInterface();
+  virtual ~ExtensionSpeechInterface();
+
+  virtual bool CheckForAvailableDevices() = 0;
+  virtual void StartRecording(
+      speech_input::SpeechRecognizerDelegate* delegate,
+      net::URLRequestContextGetter* context_getter,
+      int caller_id,
+      const std::string& language,
+      const std::string& grammar,
+      bool filter_profanities) = 0;
+
+  virtual void StopRecording(bool recognition_failed) = 0;
+  virtual bool HasValidRecognizer() const = 0;
+
+ protected:
+  scoped_refptr<speech_input::SpeechRecognizer> recognizer_;
+};
+
+// Manages the speech input requests and responses from the extensions
+// associated to the given profile.
+class ExtensionSpeechInputManager : public NotificationObserver,
+    public base::RefCountedThreadSafe<ExtensionSpeechInputManager>,
+    public speech_input::SpeechRecognizerDelegate,
+    private ExtensionSpeechInterface {
+ public:
+  enum State {
+    kIdle = 0,
+    kStarting,
+    kRecording,
+    kStopping,
+    kShutdown // Internal sink state when the profile is destroyed on shutdown.
+  };
+
+  // Structure containing the details of the speech input failed notification.
+  struct ExtensionError {
+    std::string extension_id_;
+    std::string error_;
+
+    ExtensionError(const std::string& extension_id, const std::string& error)
+        : extension_id_(extension_id), error_(error) {}
+  };
+
+  // Should not be used directly. Managed by a ProfileKeyedServiceFactory.
+  explicit ExtensionSpeechInputManager(Profile* profile);
+
+  // Returns the corresponding manager for the given profile, creating
+  // a new one if required.
+  static ExtensionSpeechInputManager* GetForProfile(Profile* profile);
+
+  // Initialize the ProfileKeyedServiceFactory.
+  static void InitializeFactory();
+
+  // Request to start speech recognition for the provided extension.
+  bool Start(const std::string& extension_id,
+             const std::string& language,
+             const std::string& grammar,
+             bool filter_profanities,
+             std::string* error);
+
+  // Request to stop an ongoing speech recognition.
+  bool Stop(const std::string& extension_id, std::string* error);
+
+  // Retrieve the actual state of the API manager.
+  State state() const { return state_; }
+
+  // Called by internal ProfileKeyedService class.
+  void ShutdownOnUIThread();
+
+  // Methods from NotificationObserver.
+  virtual void Observe(int type,
+                       const NotificationSource& source,
+                       const NotificationDetails& details) OVERRIDE;
+
+  // Methods from SpeechRecognizerDelegate.
+  virtual void SetRecognitionResult(
+      int caller_id,
+      const speech_input::SpeechInputResult& result) OVERRIDE;
+
+  virtual void DidStartReceivingAudio(int caller_id) OVERRIDE;
+  virtual void DidCompleteRecording(int caller_id) OVERRIDE;
+  virtual void DidCompleteRecognition(int caller_id) OVERRIDE;
+  virtual void DidStartReceivingSpeech(int caller_id) OVERRIDE;
+  virtual void DidStopReceivingSpeech(int caller_id) OVERRIDE;
+  virtual void OnRecognizerError(int caller_id,
+                                 speech_input::SpeechInputError error)
+                                 OVERRIDE;
+  virtual void DidCompleteEnvironmentEstimation(int caller_id) OVERRIDE;
+  virtual void SetInputVolume(int caller_id, float volume,
+                              float noise_volume) OVERRIDE {}
+
+  // Methods for API testing.
+  void SetExtensionSpeechInterface(ExtensionSpeechInterface* interface);
+  ExtensionSpeechInterface* GetExtensionSpeechInterface();
+
+ private:
+  // ExtensionSpeechInterface methods:
+  virtual bool CheckForAvailableDevices() OVERRIDE;
+  virtual bool HasValidRecognizer() const OVERRIDE;
+
+  virtual void StartRecording(
+      speech_input::SpeechRecognizerDelegate* delegate,
+      net::URLRequestContextGetter* context_getter,
+      int caller_id,
+      const std::string& language,
+      const std::string& grammar,
+      bool filter_profanities) OVERRIDE;
+
+  virtual void StopRecording(bool recognition_failed) OVERRIDE;
+
+  // Internal methods.
+  void StartOnIOThread(
+      net::URLRequestContextGetter* context_getter,
+      const std::string& language,
+      const std::string& grammar,
+      bool filter_profanities);
+  void ForceStopOnIOThread();
+
+  void SetRecognitionResultOnUIThread(
+      const speech_input::SpeechInputResult& result,
+      const std::string& extension_id);
+  void DidStartReceivingAudioOnUIThread();
+  void StopSucceededOnUIThread();
+
+  void DispatchError(const std::string& error, bool dispatch_event);
+  void DispatchEventToExtension(const std::string& extension_id,
+                                const std::string& event,
+                                const std::string& json_args);
+  void ExtensionUnloaded(const std::string& extension_id);
+
+  void ResetToIdleState();
+
+  virtual ~ExtensionSpeechInputManager();
+
+  friend class base::RefCountedThreadSafe<ExtensionSpeechInputManager>;
+  class Factory;
+
+  // Lock used to allow exclusive access to the state variable and methods that
+  // either read or write on it. This is required since the speech code
+  // operates in the IO thread while the extension code uses the UI thread.
+  base::Lock state_lock_;
+
+  // Used in the UI thread but also its raw value as notification
+  // source in the IO thread, guarded by the state lock and value.
+  Profile* profile_;
+
+  // Used in both threads, guarded by the state lock.
+  State state_;
+  std::string extension_id_in_use_;
+
+  // Used in the UI thread.
+  NotificationRegistrar registrar_;
+  ExtensionSpeechInterface* speech_interface_;
+};
+
+#endif  // CHROME_BROWSER_EXTENSIONS_SPEECH_INPUT_EXTENSION_SPEECH_INPUT_MANAGER_H_