soundtower-controller/controller/probe.py

"""Read Windows' RFCOMM service discovery results without sending app commands.

Run separately from Tk so WinRT async operations use a clean event loop.
This diagnoses the real Windows Bluetooth stack, which WSL cannot reproduce.
"""

import argparse
import asyncio
import socket
import sys
import warnings

SPP_UUID = "00001101-0000-1000-8000-00805f9b34fb"


def check_channel(address, channel):
    """Test the app's channel-1 fallback, without writing protocol bytes.

    A successful socket connection is evidence of an RFCOMM listener, not
    evidence that the Samsung control handshake or commands are accepted.
    """
    if not 1 <= channel <= 30:
        raise ValueError("RFCOMM channel must be between 1 and 30")
    if not hasattr(socket, "AF_BLUETOOTH") or not hasattr(socket, "BTPROTO_RFCOMM"):
        raise RuntimeError(
            "This Python build lacks Bluetooth sockets. Use Windows CPython 3.14 or newer."
        )
    with socket.socket(socket.AF_BLUETOOTH, socket.SOCK_STREAM, socket.BTPROTO_RFCOMM) as stream:
        stream.settimeout(10)
        stream.connect((address, channel))


async def probe(name_filter, channel=None):
    from winrt.windows.devices.bluetooth import BluetoothCacheMode, BluetoothDevice
    from winrt.windows.devices.enumeration import DeviceInformation

    selector = BluetoothDevice.get_device_selector_from_pairing_state(True)
    # Python/WinRT exposes the AQS string overload under a separate name.
    # find_all_async(selector) can instead try converting the string to a
    # DeviceClass integer, unlike the similarly named C# API.
    devices = await asyncio.wait_for(DeviceInformation.find_all_async_aqs_filter(selector), 20)
    matches = [device for device in devices if name_filter.casefold() in device.name.casefold()]
    if not matches:
        print(f"No paired Bluetooth Classic device matching {name_filter!r}.")
        print("Paired device names:", ", ".join(device.name for device in devices) or "(none)")
        return 1
    found_spp = False
    channel_open = False
    failures = False
    for info in matches:
        print(f"\nDevice: {info.name}")
        device = None
        try:
            device = await asyncio.wait_for(BluetoothDevice.from_id_async(info.id), 20)
            if device is None:
                print("Windows could not open this device. Check Bluetooth access permissions.")
                failures = True
                continue
            address_hex = f"{device.bluetooth_address:012X}"
            address = ":".join(address_hex[i : i + 2] for i in range(0, 12, 2))
            print("Bluetooth address:", address)
            # Uncached discovery asks the speaker instead of relying on the
            # cached service list used by some Windows settings screens.
            # Keep the explicit overload for compatibility with older WinRT
            # projections; recent versions retain it as a deprecated alias.
            with warnings.catch_warnings():
                warnings.filterwarnings(
                    "ignore",
                    message=r"BluetoothDevice\.get_rfcomm_services_with_cache_mode_async\(\).*",
                    category=DeprecationWarning,
                )
                result = await asyncio.wait_for(
                    device.get_rfcomm_services_with_cache_mode_async(BluetoothCacheMode.UNCACHED),
                    30,
                )
            print("Discovery status:", result.error)
            if int(result.error) != 0:
                failures = True
            if not result.services:
                print("No RFCOMM services returned. This is not proof the firmware lacks SPP.")
            for service in result.services:
                try:
                    service_uuid = str(service.service_id.uuid).lower()
                    is_spp = service_uuid == SPP_UUID
                    found_spp |= is_spp
                    print("Service:", service_uuid, "(SPP)" if is_spp else "")
                    print(
                        "Endpoint:",
                        service.connection_host_name.raw_name,
                        service.connection_service_name,
                    )
                finally:
                    service.close()
            if channel is not None:
                print(f"Testing direct RFCOMM channel {channel} (no application data)…", flush=True)
                try:
                    await asyncio.to_thread(check_channel, address, channel)
                    channel_open = True
                    print("Direct channel connection: SUCCESS")
                except Exception as exc:
                    failures = True
                    print(f"Direct channel connection: FAILED: {type(exc).__name__}: {exc}")
        except Exception as exc:
            print(f"Discovery failed: {type(exc).__name__}: {exc}")
            failures = True
        finally:
            if device is not None:
                device.close()
    print("\nSPP service found:", found_spp)
    print("No application commands were sent.")
    return 0 if (found_spp or channel_open) and not failures else 1


def main():
    if sys.platform != "win32":
        print("Run this with Windows uv.exe in PowerShell, not Linux Python in WSL.")
        return 2
    try:
        parser = argparse.ArgumentParser(description=__doc__)
        parser.add_argument("name", nargs="?", default="MX-T40")
        parser.add_argument(
            "--channel",
            type=int,
            choices=range(1, 31),
            help="Test a direct RFCOMM channel without sending app commands",
        )
        args = parser.parse_args()
        return asyncio.run(probe(args.name, args.channel))
    except ImportError as exc:
        print("Missing Windows diagnostic dependency:", exc)
        print(
            "Use: uv.exe run --with-requirements requirements-diagnostics.txt -m controller.probe"
        )
        return 2
    except Exception as exc:
        print(f"Windows Bluetooth query failed: {type(exc).__name__}: {exc}")
        return 1


if __name__ == "__main__":
    raise SystemExit(main())