Separate out the TtsController interface from it's impl

chrome/browser/speech/tts_controller_impl.h

+// Copyright (c) 2012 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_SPEECH_TTS_CONTROLLER_IMPL_H_

[sky, 2014/07/23 16:34:37]

I'm surprised this file didn't show up as a copy.

[mrunal, 2014/07/23 17:17:06]

Do u mean above header name is duplicate? or Do u mean contents of this file are
mostly copied?

[sky, 2014/07/23 19:11:06]

I meant that is this file is basically of a copy of what was in tts_controller.h
I expected it to show as a copy.

[mrunal, 2014/07/23 19:18:26]

Got it.

+#define CHROME_BROWSER_SPEECH_TTS_CONTROLLER_IMPL_H_
+
+#include <queue>
+#include <set>
+#include <string>
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/singleton.h"
+#include "base/memory/weak_ptr.h"
+#include "chrome/browser/speech/tts_controller.h"
+#include "url/gurl.h"
+
+// Singleton class that manages text-to-speech for the TTS and TTS engine
+// extension APIs, maintaining a queue of pending utterances and keeping
+// track of all state.
+class TtsControllerImpl : public TtsController {
+ public:
+  // Get the single instance of this class.
+  static TtsControllerImpl* GetInstance();
+
+  // Returns true if we're currently speaking an utterance.
+  virtual bool IsSpeaking() OVERRIDE;

[sky, 2014/07/23 16:34:37]

overrides are grouped together with no comments. See other classes for what I
mean.

[mrunal, 2014/07/23 17:17:06]

Acknowledged.

+
+  // Speak the given utterance. If the utterance's can_enqueue flag is true
+  // and another utterance is in progress, adds it to the end of the queue.
+  // Otherwise, interrupts any current utterance and speaks this one
+  // immediately.
+  virtual void SpeakOrEnqueue(Utterance* utterance) OVERRIDE;
+
+  // Stop all utterances and flush the queue. Implies leaving pause mode
+  // as well.
+  virtual void Stop() OVERRIDE;
+
+  // Pause the speech queue. Some engines may support pausing in the middle
+  // of an utterance.
+  virtual void Pause() OVERRIDE;
+
+  // Resume speaking.
+  virtual void Resume() OVERRIDE;
+
+  // Handle events received from the speech engine. Events are forwarded to
+  // the callback function, and in addition, completion and error events
+  // trigger finishing the current utterance and starting the next one, if
+  // any.
+  virtual void OnTtsEvent(int utterance_id,
+                  TtsEventType event_type,
+                  int char_index,
+                  const std::string& error_message) OVERRIDE;
+
+  // Return a list of all available voices, including the native voice,
+  // if supported, and all voices registered by extensions.
+  virtual void GetVoices(Profile* profile,
+                         std::vector<VoiceData>* out_voices) OVERRIDE;
+
+  // Called by TtsExtensionLoaderChromeOs::LoadTtsExtension when it
+  // finishes loading the built-in TTS component extension.
+  virtual void RetrySpeakingQueuedUtterances() OVERRIDE;
+
+  // Called by the extension system or platform implementation when the
+  // list of voices may have changed and should be re-queried.
+  virtual void VoicesChanged() OVERRIDE;
+
+  // Add a delegate that wants to be notified when the set of voices changes.
+  virtual void AddVoicesChangedDelegate(
+      VoicesChangedDelegate* delegate) OVERRIDE;
+
+  // Remove delegate that wants to be notified when the set of voices changes.
+  virtual void RemoveVoicesChangedDelegate(
+      VoicesChangedDelegate* delegate) OVERRIDE;
+
+  // Set the delegate that processes TTS requests with user-installed
+  // extensions.
+  virtual void SetTtsEngineDelegate(TtsEngineDelegate* delegate) OVERRIDE;
+
+  // For unit testing.
+  virtual void SetPlatformImpl(TtsPlatformImpl* platform_impl) OVERRIDE;
+  virtual int QueueSize() OVERRIDE;
+
+ protected:
+  TtsControllerImpl();
+  virtual ~TtsControllerImpl();
+
+ private:
+  // Get the platform TTS implementation (or injected mock).
+  TtsPlatformImpl* GetPlatformImpl();
+
+  // Start speaking the given utterance. Will either take ownership of
+  // |utterance| or delete it if there's an error. Returns true on success.
+  void SpeakNow(Utterance* utterance);
+
+  // Clear the utterance queue. If send_events is true, will send
+  // TTS_EVENT_CANCELLED events on each one.
+  void ClearUtteranceQueue(bool send_events);
+
+  // Finalize and delete the current utterance.
+  void FinishCurrentUtterance();
+
+  // Start speaking the next utterance in the queue.
+  void SpeakNextUtterance();
+
+  // Given an utterance and a vector of voices, return the
+  // index of the voice that best matches the utterance.
+  int GetMatchingVoice(const Utterance* utterance,
+                       std::vector<VoiceData>& voices);
+
+  friend struct DefaultSingletonTraits<TtsControllerImpl>;
+
+  // The current utterance being spoken.
+  Utterance* current_utterance_;
+
+  // Whether the queue is paused or not.
+  bool paused_;
+
+  // A queue of utterances to speak after the current one finishes.
+  std::queue<Utterance*> utterance_queue_;
+
+  // A set of delegates that want to be notified when the voices change.
+  std::set<VoicesChangedDelegate*> voices_changed_delegates_;
+
+  // A pointer to the platform implementation of text-to-speech, for
+  // dependency injection.
+  TtsPlatformImpl* platform_impl_;
+
+  // The delegate that processes TTS requests with user-installed extensions.
+  TtsEngineDelegate* tts_engine_delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(TtsControllerImpl);
+};
+
+#endif  // CHROME_BROWSER_SPEECH_TTS_CONTROLLER_IMPL_H_