import logging
import threading

logger = logging.getLogger(__name__)

_registry: dict[str, str] = {}
_registry_lock = threading.Lock()


def register_device(device_id: str, public_key_pem: str) -> None:
    with _registry_lock:
        _registry[device_id] = public_key_pem
    logger.info("Device registered: device_id=%s", device_id)
    try:
        from yuxi.channel.gateway.device_registry_db import db_save_device

        import asyncio

        try:
            loop = asyncio.get_running_loop()
            loop.create_task(db_save_device(device_id, public_key_pem))
        except RuntimeError:
            pass
    except Exception:
        logger.debug("DB device save skipped: device_id=%s", device_id)


def unregister_device(device_id: str) -> bool:
    with _registry_lock:
        if device_id in _registry:
            del _registry[device_id]
            logger.info("Device unregistered: device_id=%s", device_id)
            return True
        return False


async def lookup_public_key(device_id: str) -> str | None:
    with _registry_lock:
        key = _registry.get(device_id)
    if key is not None:
        return key
    key = await _db_lookup(device_id)
    if key is not None:
        with _registry_lock:
            _registry[device_id] = key
    return key


async def _db_lookup(device_id: str) -> str | None:
    try:
        from yuxi.channel.gateway.device_registry_db import db_lookup_public_key

        return await db_lookup_public_key(device_id)
    except Exception:
        logger.debug("DB device lookup skipped: device_id=%s", device_id)
        return None


def list_devices() -> list[str]:
    with _registry_lock:
        return list(_registry.keys())