import asyncio
import threading
from typing import Callable, Awaitable

import redis

room_set_key = "bilibili:live:danmu:room_set"
r: redis.Redis | None = None
on_room_changed: Callable[[list[int]], Awaitable[None]] | None = None


def init(redis_conf: dict | None) -> None:
    global r

    if redis_conf is None:
        return

    r = redis.Redis(
        host=redis_conf.get("host", "127.0.0.1"),
        port=redis_conf.get("port", 6379),
        db=redis_conf.get("port", 0),
    )

    asyncio.create_task(_subscribe_redis_async())


def get_room_list() -> list[int]:
    if r is None:
        return []

    return [int(room_id) for room_id in r.smembers(room_set_key)]


async def _subscribe_redis_async():
    p = r.pubsub()
    p.subscribe(f"__keyspace@0__:{room_set_key}")
    while p.subscribed:
        msg = await asyncio.to_thread(p.get_message, ignore_subscribe_messages=True, timeout=1)
        if msg and on_room_changed is not None:
            await on_room_changed(get_room_list())