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