From f6356e3830d51ff6021e7714d4720147bf8b36ab Mon Sep 17 00:00:00 2001
From: Andrew Leech <andrew.leech@planetinnovation.com.au>
Date: Tue, 13 Aug 2019 18:22:34 +1000
Subject: [PATCH] .net: Enable active scanning during discovery and check scan
 responses for local name.

---
 bleak/backends/dotnet/discovery.py | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/bleak/backends/dotnet/discovery.py b/bleak/backends/dotnet/discovery.py
index 22818e34..dded0062 100644
--- a/bleak/backends/dotnet/discovery.py
+++ b/bleak/backends/dotnet/discovery.py
@@ -18,7 +18,8 @@
 
 from System import Array, Byte
 from Windows.Devices import Enumeration
-from Windows.Devices.Bluetooth.Advertisement import BluetoothLEAdvertisementWatcher
+from Windows.Devices.Bluetooth.Advertisement import \
+    BluetoothLEAdvertisementWatcher, BluetoothLEScanningMode, BluetoothLEAdvertisementType
 from Windows.Storage.Streams import DataReader, IBuffer
 
 logger = logging.getLogger(__name__)
@@ -47,6 +48,7 @@ async def discover(
     watcher = BluetoothLEAdvertisementWatcher()
 
     devices = {}
+    scan_responses = {}
 
     def _format_bdaddr(a):
         return ":".join("{:02X}".format(x) for x in a.to_bytes(6, byteorder="big"))
@@ -63,8 +65,12 @@ def _format_event_args(e):
     def AdvertisementWatcher_Received(sender, e):
         if sender == watcher:
             logger.debug("Received {0}.".format(_format_event_args(e)))
-            if e.BluetoothAddress not in devices:
-                devices[e.BluetoothAddress] = e
+            if e.AdvertisementType == BluetoothLEAdvertisementType.ScanResponse:
+                if e.BluetoothAddress not in scan_responses:
+                    scan_responses[e.BluetoothAddress] = e
+            else:
+                if e.BluetoothAddress not in devices:
+                    devices[e.BluetoothAddress] = e
 
     def AdvertisementWatcher_Stopped(sender, e):
         if sender == watcher:
@@ -77,6 +83,8 @@ def AdvertisementWatcher_Stopped(sender, e):
     watcher.Received += AdvertisementWatcher_Received
     watcher.Stopped += AdvertisementWatcher_Stopped
 
+    watcher.ScanningMode = BluetoothLEScanningMode.Active
+
     # Watcher works outside of the Python process.
     watcher.Start()
     await asyncio.sleep(timeout, loop=loop)
@@ -101,10 +109,13 @@ def AdvertisementWatcher_Stopped(sender, e):
             reader = DataReader.FromBuffer(md)
             reader.ReadBytes(b)
             data[m.CompanyId] = bytes(b)
+        local_name = d.Advertisement.LocalName
+        if not local_name and d.BluetoothAddress in scan_responses:
+            local_name = scan_responses[d.BluetoothAddress].Advertisement.LocalName
         found.append(
             BLEDevice(
                 bdaddr,
-                d.Advertisement.LocalName,
+                local_name,
                 d,
                 uuids=uuids,
                 manufacturer_data=data,