Bug 1191814 - WebSpeech synthesis API and AudioChannelService, r=eeejay

dom/media/webspeech/synth/ipc/PSpeechSynthesisRequest.ipdl

@@ -23,6 +23,8 @@ async protocol PSpeechSynthesisRequest
 
   ForceEnd();
 
+  SetAudioOutputVolume(uint32_t aVolume);
+
  child:
 
   __delete__(bool aIsError, float aElapsedTime, uint32_t aCharIndex);

dom/media/webspeech/synth/ipc/SpeechSynthesisChild.cpp

@@ -191,5 +191,13 @@ SpeechTaskChild::ForceEnd()
   mActor->SendForceEnd();
 }
 
+void
+SpeechTaskChild::SetAudioOutputVolume(uint32_t aVolume)
+{
+  if (mActor) {
+    mActor->SendSetAudioOutputVolume(aVolume);
+  }
+}
+
 } // namespace dom
 } // namespace mozilla

dom/media/webspeech/synth/ipc/SpeechSynthesisChild.h

@@ -92,6 +92,8 @@ public:
 
   virtual void ForceEnd() override;
 
+  virtual void SetAudioOutputVolume(uint32_t aVolume) override;
+
 private:
   SpeechSynthesisRequestChild* mActor;
 };

dom/media/webspeech/synth/ipc/SpeechSynthesisParent.cpp

@@ -127,6 +127,14 @@ SpeechSynthesisRequestParent::RecvForceEnd()
   return true;
 }
 
+bool
+SpeechSynthesisRequestParent::RecvSetAudioOutputVolume(const uint32_t& aVolume)
+{
+  MOZ_ASSERT(mTask);
+  mTask->SetAudioOutputVolume(aVolume);
+  return true;
+}
+
 // SpeechTaskParent
 
 nsresult

dom/media/webspeech/synth/ipc/SpeechSynthesisParent.h

@@ -69,6 +69,8 @@ protected:
   virtual bool RecvCancel() override;
 
   virtual bool RecvForceEnd() override;
+
+  virtual bool RecvSetAudioOutputVolume(const uint32_t& aVolume) override;
 };
 
 class SpeechTaskParent : public nsSpeechTask

dom/media/webspeech/synth/nsSpeechTask.cpp

@@ -4,10 +4,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+#include "AudioChannelAgent.h"
+#include "AudioChannelService.h"
 #include "AudioSegment.h"
 #include "nsSpeechTask.h"
-#include "SpeechSynthesis.h"
 #include "nsSynthVoiceRegistry.h"
+#include "SpeechSynthesis.h"
 
 // GetCurrentTime is defined in winbase.h as zero argument macro forwarding to
 // GetTickCount() and conflicts with nsSpeechTask::GetCurrentTime().
@@ -89,6 +91,7 @@ NS_IMPL_CYCLE_COLLECTION(nsSpeechTask, mSpeechSynthesis, mUtterance, mCallback);
 
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsSpeechTask)
   NS_INTERFACE_MAP_ENTRY(nsISpeechTask)
+  NS_INTERFACE_MAP_ENTRY(nsIAudioChannelAgentCallback)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsISpeechTask)
 NS_INTERFACE_MAP_END
 
@@ -314,6 +317,8 @@ nsSpeechTask::DispatchStart()
 nsresult
 nsSpeechTask::DispatchStartInner()
 {
+  CreateAudioChannelAgent();
+
   nsSynthVoiceRegistry::GetInstance()->SetIsSpeaking(true);
   return DispatchStartImpl();
 }
@@ -356,6 +361,8 @@ nsSpeechTask::DispatchEnd(float aElapsedTime, uint32_t aCharIndex)
 nsresult
 nsSpeechTask::DispatchEndInner(float aElapsedTime, uint32_t aCharIndex)
 {
+  DestroyAudioChannelAgent();
+
   if (!mPreCanceled) {
     nsSynthVoiceRegistry::GetInstance()->SpeakNext();
   }
@@ -645,5 +652,53 @@ nsSpeechTask::SetSpeechSynthesis(SpeechSynthesis* aSpeechSynthesis)
   mSpeechSynthesis = aSpeechSynthesis;
 }
 
+void
+nsSpeechTask::CreateAudioChannelAgent()
+{
+  if (!mUtterance) {
+    return;
+  }
+
+  if (mAudioChannelAgent) {
+    mAudioChannelAgent->NotifyStoppedPlaying(nsIAudioChannelAgent::AUDIO_AGENT_NOTIFY);
+  }
+
+  mAudioChannelAgent = new AudioChannelAgent();
+  mAudioChannelAgent->InitWithWeakCallback(mUtterance->GetOwner(),
+                                           static_cast<int32_t>(AudioChannelService::GetDefaultAudioChannel()),
+                                           this);
+}
+
+void
+nsSpeechTask::DestroyAudioChannelAgent()
+{
+  if (mAudioChannelAgent) {
+    mAudioChannelAgent->NotifyStoppedPlaying(nsIAudioChannelAgent::AUDIO_AGENT_NOTIFY);
+    mAudioChannelAgent = nullptr;
+  }
+}
+
+NS_IMETHODIMP
+nsSpeechTask::WindowVolumeChanged(float aVolume, bool aMuted)
+{
+  SetAudioOutputVolume(mVolume * aVolume * aMuted);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSpeechTask::WindowAudioCaptureChanged()
+{
+  // This is not supported yet.
+  return NS_OK;
+}
+
+void
+nsSpeechTask::SetAudioOutputVolume(uint32_t aVolume)
+{
+  if (mStream) {
+    mStream->SetAudioOutputVolume(this, aVolume);
+  }
+}
+
 } // namespace dom
 } // namespace mozilla

dom/media/webspeech/synth/nsSpeechTask.h

@@ -9,6 +9,7 @@
 
 #include "MediaStreamGraph.h"
 #include "SpeechSynthesisUtterance.h"
+#include "nsIAudioChannelAgent.h"
 #include "nsISpeechService.h"
 
 namespace mozilla {
@@ -19,6 +20,7 @@ class SpeechSynthesis;
 class SynthStreamListener;
 
 class nsSpeechTask : public nsISpeechTask
+                   , public nsIAudioChannelAgentCallback
 {
   friend class SynthStreamListener;
 
@@ -27,6 +29,7 @@ public:
   NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(nsSpeechTask, nsISpeechTask)
 
   NS_DECL_NSISPEECHTASK
+  NS_DECL_NSIAUDIOCHANNELAGENTCALLBACK
 
   explicit nsSpeechTask(SpeechSynthesisUtterance* aUtterance);
   nsSpeechTask(float aVolume, const nsAString& aText);
@@ -49,6 +52,8 @@ public:
 
   void SetChosenVoiceURI(const nsAString& aUri);
 
+  virtual void SetAudioOutputVolume(uint32_t aVolume);
+
   bool IsPreCanceled()
   {
     return mPreCanceled;
@@ -102,12 +107,18 @@ private:
 
   nsresult DispatchEndInner(float aElapsedTime, uint32_t aCharIndex);
 
+  void CreateAudioChannelAgent();
+
+  void DestroyAudioChannelAgent();
+
   nsRefPtr<SourceMediaStream> mStream;
 
   nsRefPtr<MediaInputPort> mPort;
 
   nsCOMPtr<nsISpeechTaskCallback> mCallback;
 
+  nsCOMPtr<nsIAudioChannelAgent> mAudioChannelAgent;
+
   uint32_t mChannels;
 
   nsRefPtr<SpeechSynthesis> mSpeechSynthesis;