chrome/browser/speech/tts_controller_impl.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_SPEECH_TTS_CONTROLLER_IMPL_H_
   6 #define CHROME_BROWSER_SPEECH_TTS_CONTROLLER_IMPL_H_
   7
   8 #include <queue>
   9 #include <set>
  10 #include <string>
  11 #include <vector>
  12
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/memory/singleton.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "chrome/browser/speech/tts_controller.h"
  17 #include "url/gurl.h"
  18
  19 namespace content {
  20 class BrowserContext;
  21 }
  22
  23 // Singleton class that manages text-to-speech for the TTS and TTS engine
  24 // extension APIs, maintaining a queue of pending utterances and keeping
  25 // track of all state.
  26 class TtsControllerImpl : public TtsController {
  27  public:
  28   // Get the single instance of this class.
  29   static TtsControllerImpl* GetInstance();
  30
  31   // TtsController methods
  32   virtual bool IsSpeaking() OVERRIDE;
  33   virtual void SpeakOrEnqueue(Utterance* utterance) OVERRIDE;
  34   virtual void Stop() OVERRIDE;
  35   virtual void Pause() OVERRIDE;
  36   virtual void Resume() OVERRIDE;
  37   virtual void OnTtsEvent(int utterance_id,
  38                   TtsEventType event_type,
  39                   int char_index,
  40                   const std::string& error_message) OVERRIDE;
  41   virtual void GetVoices(content::BrowserContext* browser_context,
  42                          std::vector<VoiceData>* out_voices) OVERRIDE;
  43   virtual void VoicesChanged() OVERRIDE;
  44   virtual void AddVoicesChangedDelegate(
  45       VoicesChangedDelegate* delegate) OVERRIDE;
  46   virtual void RemoveVoicesChangedDelegate(
  47       VoicesChangedDelegate* delegate) OVERRIDE;
  48   virtual void SetTtsEngineDelegate(TtsEngineDelegate* delegate) OVERRIDE;
  49   virtual TtsEngineDelegate* GetTtsEngineDelegate() OVERRIDE;
  50   virtual void SetPlatformImpl(TtsPlatformImpl* platform_impl) OVERRIDE;
  51   virtual int QueueSize() OVERRIDE;
  52
  53  protected:
  54   TtsControllerImpl();
  55   virtual ~TtsControllerImpl();
  56
  57  private:
  58   // Get the platform TTS implementation (or injected mock).
  59   TtsPlatformImpl* GetPlatformImpl();
  60
  61   // Start speaking the given utterance. Will either take ownership of
  62   // |utterance| or delete it if there's an error. Returns true on success.
  63   void SpeakNow(Utterance* utterance);
  64
  65   // Clear the utterance queue. If send_events is true, will send
  66   // TTS_EVENT_CANCELLED events on each one.
  67   void ClearUtteranceQueue(bool send_events);
  68
  69   // Finalize and delete the current utterance.
  70   void FinishCurrentUtterance();
  71
  72   // Start speaking the next utterance in the queue.
  73   void SpeakNextUtterance();
  74
  75   // Given an utterance and a vector of voices, return the
  76   // index of the voice that best matches the utterance.
  77   int GetMatchingVoice(const Utterance* utterance,
  78                        std::vector<VoiceData>& voices);
  79
  80   friend struct DefaultSingletonTraits<TtsControllerImpl>;
  81
  82   // The current utterance being spoken.
  83   Utterance* current_utterance_;
  84
  85   // Whether the queue is paused or not.
  86   bool paused_;
  87
  88   // A queue of utterances to speak after the current one finishes.
  89   std::queue<Utterance*> utterance_queue_;
  90
  91   // A set of delegates that want to be notified when the voices change.
  92   std::set<VoicesChangedDelegate*> voices_changed_delegates_;
  93
  94   // A pointer to the platform implementation of text-to-speech, for
  95   // dependency injection.
  96   TtsPlatformImpl* platform_impl_;
  97
  98   // The delegate that processes TTS requests with user-installed extensions.
  99   TtsEngineDelegate* tts_engine_delegate_;
 100
 101   DISALLOW_COPY_AND_ASSIGN(TtsControllerImpl);
 102 };
 103
 104 #endif  // CHROME_BROWSER_SPEECH_TTS_CONTROLLER_IMPL_H_