Bug 793950 - v2: Handle volume change in BluetoothHfpManager, r=qdot

dom/bluetooth/BluetoothHfpManager.cpp

@@ -4,18 +4,25 @@
  * 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 "base/basictypes.h"
 #include "BluetoothHfpManager.h"
 
 #include "BluetoothReplyRunnable.h"
 #include "BluetoothService.h"
 #include "BluetoothServiceUuid.h"
 
+#include "mozilla/dom/bluetooth/BluetoothTypes.h"
 #include "mozilla/Services.h"
+#include "nsContentUtils.h"
 #include "nsIObserverService.h"
 #include "nsIRadioInterfaceLayer.h"
+#include "nsVariant.h"
 
 #include <unistd.h> /* usleep() */
 
+#define MOZSETTINGS_CHANGED_ID "mozsettings-changed"
+#define AUDIO_VOLUME_MASTER "audio.volume.master"
+
 USING_BLUETOOTH_NAMESPACE
 using namespace mozilla::ipc;
 
@@ -25,6 +32,8 @@ static bool sStopSendingRingFlag = true;
 
 static int kRingInterval = 3000000;  //unit: us
 
+NS_IMPL_ISUPPORTS1(BluetoothHfpManager, nsIObserver)
+
 class SendRingIndicatorTask : public nsRunnable
 {
 public:
@@ -52,6 +61,11 @@ BluetoothHfpManager::BluetoothHfpManager()
   , mCurrentCallIndex(0)
   , mCurrentCallState(nsIRadioInterfaceLayer::CALL_STATE_DISCONNECTED)
 {
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+
+  if (obs && NS_FAILED(obs->AddObserver(sInstance, MOZSETTINGS_CHANGED_ID, false))) {
+    NS_WARNING("Failed to add settings change observer!");
+  }
 }
 
 BluetoothHfpManager::~BluetoothHfpManager()
@@ -71,6 +85,99 @@ BluetoothHfpManager::Get()
   return sInstance;
 }
 
+nsresult
+BluetoothHfpManager::HandleVolumeChanged(const nsAString& aData)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // The string that we're interested in will be a JSON string that looks like:
+  //  {"key":"volumeup", "value":1.0}
+  //  {"key":"volumedown", "value":0.2}
+
+  JSContext* cx = nsContentUtils::GetSafeJSContext();
+  if (!cx) {
+    return NS_OK;
+  }
+
+  JS::Value val;
+  if (!JS_ParseJSON(cx, aData.BeginReading(), aData.Length(), &val)) {
+    return JS_ReportPendingException(cx) ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  if (!val.isObject()) {
+    return NS_OK;
+  }
+
+  JSObject& obj(val.toObject());
+
+  JS::Value key;
+  if (!JS_GetProperty(cx, &obj, "key", &key)) {
+    MOZ_ASSERT(!JS_IsExceptionPending(cx));
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  if (!key.isString()) {
+    return NS_OK;
+  }
+
+  JSBool match;
+  if (!JS_StringEqualsAscii(cx, key.toString(), AUDIO_VOLUME_MASTER, &match)) {
+    MOZ_ASSERT(!JS_IsExceptionPending(cx));
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  if (!match) {
+    return NS_OK;
+  }
+
+  JS::Value value;
+  if (!JS_GetProperty(cx, &obj, "value", &value)) {
+    MOZ_ASSERT(!JS_IsExceptionPending(cx));
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  if (!value.isNumber()) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  // AG volume range: [0.0, 1.0]
+  float volume = value.toNumber();
+
+  // HS volume range: [0, 15]
+  mCurrentVgs = ceil(volume * 15);
+
+  nsDiscriminatedUnion du;
+  du.mType = 0;
+  du.u.mInt8Value = mCurrentVgs;
+
+  nsCString vgs;
+  if (NS_FAILED(nsVariant::ConvertToACString(du, vgs))) {
+    NS_WARNING("Failed to convert volume to string");
+    return NS_ERROR_FAILURE;
+  }
+
+  nsAutoCString newVgs;
+  newVgs += "+VGS: ";
+  newVgs += vgs;
+
+  SendLine(newVgs.get());
+
+  return NS_OK;
+}
+
+nsresult
+BluetoothHfpManager::Observe(nsISupports* aSubject,
+                             const char* aTopic,
+                             const PRUnichar* aData)
+{
+  if (!strcmp(aTopic, MOZSETTINGS_CHANGED_ID)) {
+    return HandleVolumeChanged(nsDependentString(aData));
+  } else {
+    MOZ_ASSERT(false, "BluetoothHfpManager got unexpected topic!");
+  }
+  return NS_ERROR_UNEXPECTED;
+}
+
 // Virtual function of class SocketConsumer
 void
 BluetoothHfpManager::ReceiveSocketData(UnixSocketRawData* aMessage)

dom/bluetooth/BluetoothHfpManager.h

@@ -9,14 +9,19 @@
 
 #include "BluetoothCommon.h"
 #include "mozilla/ipc/UnixSocket.h"
+#include "nsIObserver.h"
 
 BEGIN_BLUETOOTH_NAMESPACE
 
 class BluetoothReplyRunnable;
 
 class BluetoothHfpManager : public mozilla::ipc::UnixSocketConsumer
+                          , public nsIObserver
 {
 public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+
   ~BluetoothHfpManager();
 
   static BluetoothHfpManager* Get();
@@ -32,6 +37,8 @@ public:
 private:
   BluetoothHfpManager();
 
+  nsresult HandleVolumeChanged(const nsAString& aData);
+
   int mCurrentVgs;
   int mCurrentCallIndex;
   int mCurrentCallState;