#!/usr/bin/env python3
"""BlueZ helpers for connected devices (RSSI / disconnect). Advertising is via bless."""
from __future__ import annotations

import logging
from typing import Optional

log = logging.getLogger("collector.bluez_adv")

dbus = None
try:
    import dbus as _dbus

    dbus = _dbus
except Exception:  # pragma: no cover
    dbus = None

BLUEZ = "org.bluez"
PROPS = "org.freedesktop.DBus.Properties"
OBJECT_MANAGER = "org.freedesktop.DBus.ObjectManager"


def system_bus():
    if dbus is None:
        raise RuntimeError("python3-dbus required")
    return dbus.SystemBus()


def read_device_rssi(bus, device_path: str) -> Optional[int]:
    if dbus is None:
        return None
    try:
        obj = bus.get_object(BLUEZ, device_path)
        props = dbus.Interface(obj, PROPS)
        return int(props.Get("org.bluez.Device1", "RSSI"))
    except Exception:
        return None


def find_device_path(bus, addr: str) -> Optional[str]:
    if dbus is None:
        return None
    addr_u = (addr or "").upper()
    try:
        obj = bus.get_object(BLUEZ, "/")
        mgr = dbus.Interface(obj, OBJECT_MANAGER)
        for path, ifaces in mgr.GetManagedObjects().items():
            dev = ifaces.get("org.bluez.Device1")
            if not dev:
                continue
            if str(dev.get("Address", "")).upper() == addr_u:
                return str(path)
    except Exception as e:
        log.debug("find_device: %s", e)
    return None


def disconnect_device(bus, addr: str) -> None:
    path = find_device_path(bus, addr)
    if not path:
        return
    try:
        obj = bus.get_object(BLUEZ, path)
        dbus.Interface(obj, "org.bluez.Device1").Disconnect()
    except Exception as e:
        log.warning("disconnect %s: %s", addr, e)


def list_connected_addresses(bus) -> list:
    if dbus is None:
        return []
    out = []
    try:
        obj = bus.get_object(BLUEZ, "/")
        mgr = dbus.Interface(obj, OBJECT_MANAGER)
        for _path, ifaces in mgr.GetManagedObjects().items():
            dev = ifaces.get("org.bluez.Device1")
            if not dev:
                continue
            if bool(dev.get("Connected", False)):
                out.append(str(dev.get("Address", "")).upper())
    except Exception as e:
        log.debug("list_connected: %s", e)
    return out