i3-companion: get battery level from BlueZ

This is made available with PulseAudio 16, exposed to BlueZ with
experimental support. Also available in upower, but we are already
interacting with BlueZ, so...

bin/i3-companion

@@ -739,18 +739,16 @@ async def bluetooth_notifications(i3, event, path, interface, changed, invalid):
             and "Connected" in args[1]
             or args[0] == "org.bluez.Adapter1"
             and "Powered" in args[1]
+            or args[0] == "org.bluez.Battery1"
+            and "Percentage" in args[1]
         ),
     ),
 )
-@static(scheduled=None)
 @retry(2)
 @debounce(0.2)
 @polybar("bluetooth")
 async def bluetooth_status(i3, event, *args):
     """Update bluetooth status for Polybar."""
-    if bluetooth_status.scheduled:
-        bluetooth_status.scheduled.cancel()
-        bluetooth_status.scheduled = None
     if event is StartEvent:
         # Do we have a bluetooth device?
         if not os.path.exists("/sys/class/bluetooth"):
@@ -772,17 +770,18 @@ async def bluetooth_status(i3, event, *args):
                 powered = True
         elif "org.bluez.Device1" in interfaces:
             # We have a device!
-            device = interfaces["org.bluez.Device1"]
+            device = types.SimpleNamespace(major=0, minor=0, battery=None)
-            if not device["Connected"][1]:
+            interface = interfaces["org.bluez.Device1"]
+            if not interface["Connected"][1]:
                 continue
             try:
-                device_class = device["Class"][1]
+                device_class = interface["Class"][1]
-                major = (device_class & 0x1F00) >> 8
+                device.major = (device_class & 0x1F00) >> 8
-                minor = (device_class & 0xFC) >> 2
+                device.minor = (device_class & 0xFC) >> 2
-                mac = device["Address"][1]
+                device.battery = interfaces["org.bluez.Battery1"]["Percentage"][1]
-                devices.append((major, minor, mac))
             except KeyError:
-                devices.append((0, 0, ""))
+                pass
+            devices.append(device)
 
     # Choose appropriate icons for output
     # See: https://btprodspecificationrefs.blob.core.windows.net/assigned-numbers
@@ -791,7 +790,7 @@ async def bluetooth_status(i3, event, *args):
         output = ""
     else:
         output = ["bluetooth"]
-        for major, minor, mac in devices:
+        for device in devices:
             classes = {
                 1: "laptop",
                 2: "phone",
@@ -817,54 +816,18 @@ async def bluetooth_status(i3, event, *args):
                     (lambda x: x & 0x20, "printer"),
                 ],
             }
-            icon = classes.get((major, minor)) or classes.get(major, "unknown")
+            icon = classes.get((device.major, device.minor)) or classes.get(device.major, "unknown")
             if type(icon) is list:
                 for matcher, name in icon:
-                    if matcher(minor):
+                    if matcher(device.minor):
                         icon = name
                         break
                 else:
                     icon = "unknown"
             output.append(icon)
-            if mac.startswith("2C:41:A1"):
+            if device.battery is not None:
-                # Get battery status for BOSE QC 35 II. This is hacky.
+                icon = f"battery-{(device.battery+12)//25*25}"
-                # For other headsets, the information could be
-                # available through upower DBus. See
-                # https://github.com/Denton-L/based-connect. Starting
-                # from PA 16, it may be exposed by PA, then to BlueZ.
-                # See
-                # https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/merge_requests/482
-                loop = asyncio.get_event_loop()
-                sock = socket.socket(
-                    socket.AF_BLUETOOTH, socket.SOCK_STREAM, socket.BTPROTO_RFCOMM
-                )
-                try:
-                    sock.setblocking(False)
-                    # Workaround a bug in asyncio: https://bugs.python.org/issue27929
-                    fut = loop.create_future()
-                    loop._sock_connect(fut, sock, (mac, 8))
-                    await fut
-                    # Get battery
-                    for send, ack, size in (
-                        (b"\0\1\1\0", b"\0\1\3\5", 5),  # get firmware
-                        (b"\2\2\1\0", b"\2\2\3\1", 1),  # get battery
-                    ):
-                        await loop.sock_sendall(sock, send)
-                        rack = await loop.sock_recv(sock, len(ack))
-                        assert rack == ack, "incorrect ack received"
-                        result = await loop.sock_recv(sock, size)
-                    battery = result[0]
-                finally:
-                    sock.close()
-                # Choose an icon
-                icon = f"battery-{(battery+12)//25*25}"
                 output[-1] = (output[-1], icon)
-
-                # Schedule a refresh in 5 minutes
-                bluetooth_status.scheduled = loop.call_later(
-                    600,
-                    lambda: asyncio.create_task(bluetooth_status(i3, StartEvent)),
-                )
         return "|".join(
             (" ".join(icons[oo] for oo in o) if type(o) is tuple else icons[o])
             for o in output