import threading
from typing import Callable

import redis

room_list_key = "bilibili.live.danmu.room_list"
r: redis.Redis | None = None
on_room_changed: Callable[[list[int]], None] = lambda ignore: None


def init(redis_conf: dict | 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),
    )

    # run subscribe_redis on new thread
    threading.Thread(target=subscribe_redis, daemon=True).start()


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

    return [int(room_id) for room_id in set(r.lrange(room_list_key, 0, -1))]


def subscribe_redis():
    p = r.pubsub()
    p.psubscribe(**{f"__keyspace@0__:{room_list_key}": room_changed_handler})
    for message in p.listen():
        pass


# noinspection PyUnusedLocal
def room_changed_handler(ignore):
    on_room_changed(get_room_list())