"""Push Wi-Fi TCP connect/disconnect updates to browser WebSocket clients."""

import json
import threading
from typing import Any, Set

# Threading lock: safe across asyncio tasks and avoids binding asyncio.Lock to the wrong loop.
_clients_lock = threading.Lock()
_clients: Set[Any] = set()


async def register_device_status_ws(ws: Any) -> None:
    with _clients_lock:
        _clients.add(ws)


async def unregister_device_status_ws(ws: Any) -> None:
    with _clients_lock:
        _clients.discard(ws)


async def broadcast_device_tcp_status(ip: str, connected: bool) -> None:
    from models.tcp_clients import normalize_tcp_peer_ip

    ip = normalize_tcp_peer_ip(ip)
    if not ip:
        return
    msg = json.dumps({"type": "device_tcp", "ip": ip, "connected": bool(connected)})
    with _clients_lock:
        targets = list(_clients)
    dead = []
    for ws in targets:
        try:
            await ws.send(msg)
        except Exception as exc:
            dead.append(ws)
            print(f"[device_status_broadcaster] ws.send failed: {exc!r}")
    if dead:
        with _clients_lock:
            for ws in dead:
                _clients.discard(ws)


async def broadcast_device_tcp_snapshot_to(ws: Any) -> None:
    from models import tcp_clients as tcp

    ips = tcp.list_connected_ips()
    msg = json.dumps({"type": "device_tcp_snapshot", "connected_ips": ips})
    try:
        await ws.send(msg)
    except Exception as exc:
        print(f"[device_status_broadcaster] snapshot send failed: {exc!r}")