Bluetooth API: improve discovery

chrome/browser/chromeos/extensions/bluetooth_event_router.cc

Index: chrome/browser/chromeos/extensions/bluetooth_event_router.cc
diff --git a/chrome/browser/chromeos/extensions/bluetooth_event_router.cc b/chrome/browser/chromeos/extensions/bluetooth_event_router.cc
index 8cd0b0c61442555914aec47feb195201aec83228..2b4e774420162ab3529c66e5a20f3d69cbbd14b8 100644
--- a/chrome/browser/chromeos/extensions/bluetooth_event_router.cc
+++ b/chrome/browser/chromeos/extensions/bluetooth_event_router.cc
@@ -7,6 +7,7 @@
 #include <map>
 
 #include "base/json/json_writer.h"
+#include "base/memory/linked_ptr.h"
 #include "base/memory/ref_counted.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/chromeos/bluetooth/bluetooth_adapter.h"
@@ -17,6 +18,8 @@
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/common/extensions/api/experimental_bluetooth.h"
 
+namespace experimental_bluetooth = extensions::api::experimental_bluetooth;
+
 namespace chromeos {
 
 ExtensionBluetoothEventRouter::ExtensionBluetoothEventRouter(Profile* profile)
@@ -63,7 +66,25 @@ scoped_refptr<BluetoothSocket> ExtensionBluetoothEventRouter::GetSocket(
   return socket_entry->second;
 }
 
+void ExtensionBluetoothEventRouter::SetResponsibleForDiscovery(
+    bool responsible) {
+  responsible_for_discovery_ = responsible;
+}
+
+bool ExtensionBluetoothEventRouter::IsResponsibleForDiscovery() const {
+  return responsible_for_discovery_;
+}
+
 void ExtensionBluetoothEventRouter::SetSendDiscoveryEvents(bool should_send) {
+  // At the transition into sending devices, also send past devices that
+  // were discovered as they will not be discovered again.
+  if (should_send && !send_discovery_events_) {
+    for (DeviceList::const_iterator i = discovered_devices_.begin();
+        i != discovered_devices_.end(); ++i) {
+      DispatchDeviceEvent(**i);
+    }
+  }
+
   send_discovery_events_ = should_send;
 }
 
@@ -98,6 +119,13 @@ void ExtensionBluetoothEventRouter::AdapterDiscoveringChanged(
     return;
   }
 
+  if (!discovering) {
+    send_discovery_events_ = false;
+    responsible_for_discovery_ = false;
+
+    STLClearObject(&discovered_devices_);
+  }
+
   DispatchBooleanValueEvent(
       extensions::event_names::kBluetoothOnDiscoveringChanged,
       discovering);
@@ -105,38 +133,45 @@ void ExtensionBluetoothEventRouter::AdapterDiscoveringChanged(
 
 void ExtensionBluetoothEventRouter::DeviceAdded(
     chromeos::BluetoothAdapter* adapter, chromeos::BluetoothDevice* device) {
-  if (!send_discovery_events_)
+  if (adapter != adapter_.get()) {
+    DVLOG(1) << "Ignoring event for adapter " << adapter->address();
     return;
+  }
 
-  DCHECK(adapter == adapter_.get());
+  experimental_bluetooth::Device* extension_device =
+    new experimental_bluetooth::Device();
+  experimental_bluetooth::BluetoothDeviceToApiDevice(*device, extension_device);
+  discovered_devices_.push_back(make_linked_ptr(extension_device));
 
-  extensions::api::experimental_bluetooth::Device extension_device;
-  extensions::api::experimental_bluetooth::BluetoothDeviceToApiDevice(
-      *device, &extension_device);
+  if (!send_discovery_events_)
+    return;
 
+  DispatchDeviceEvent(*extension_device);
+}
+
+void ExtensionBluetoothEventRouter::DispatchBooleanValueEvent(
+    const char* event_name, bool value) {
   ListValue args;
-  args.Append(extension_device.ToValue().release());
+  args.Append(Value::CreateBooleanValue(value));
   std::string json_args;
   base::JSONWriter::Write(&args, &json_args);
 
   profile_->GetExtensionEventRouter()->DispatchEventToRenderers(
-      extensions::event_names::kBluetoothOnDeviceDiscovered,
-      json_args,
-      NULL,
-      GURL());
+      event_name, json_args, NULL, GURL());
 }
 
-void ExtensionBluetoothEventRouter::DispatchBooleanValueEvent(
-    const char* event_name, bool value) {
+void ExtensionBluetoothEventRouter::DispatchDeviceEvent(
+    const experimental_bluetooth::Device& device) {

[asargent_no_longer_on_chrome, 2012/08/03 23:35:23]

Can you call HasEventListener on the extension event router here and early out
(avoiding building up the JSON) if no one is listening?

[bryeung, 2012/08/07 14:22:12]

I'd prefer to leave it out, if you don't mind.

That would require repeating the event name, which makes the code less
maintainable IMO.  Also, gdk@ has a refactoring coming soon (should land today
or tomorrow) that removes the need to build the JSON altogether.

[asargent_no_longer_on_chrome, 2012/08/07 15:32:48]

Ok, no problem.

   ListValue args;
-  args.Append(Value::CreateBooleanValue(value));
+  args.Append(device.ToValue().release());
   std::string json_args;
   base::JSONWriter::Write(&args, &json_args);
 
-  // TODO(bryeung): only dispatch the event to interested renderers
-  // crbug.com/133179
   profile_->GetExtensionEventRouter()->DispatchEventToRenderers(
-      event_name, json_args, NULL, GURL());
+      extensions::event_names::kBluetoothOnDeviceDiscovered,
+      json_args,
+      NULL,
+      GURL());
 }
 
 }  // namespace chromeos