import json
from collections.abc import Awaitable, Callable

from redis.asyncio import Redis

from app.config.settings import settings


class RedisRealtimeRepository:
    def __init__(self) -> None:
        self._redis: Redis | None = None
        self._pubsub = None

    async def connect(self) -> None:
        if self._redis:
            return
        self._redis = Redis.from_url(settings.redis_url, decode_responses=True)
        self._pubsub = self._redis.pubsub()
        await self._pubsub.psubscribe("chat:*")

    async def close(self) -> None:
        if self._pubsub:
            await self._pubsub.close()
            self._pubsub = None
        if self._redis:
            await self._redis.aclose()
            self._redis = None

    async def publish_event(self, channel: str, payload: dict) -> None:
        if not self._redis:
            await self.connect()
        assert self._redis is not None
        await self._redis.publish(channel, json.dumps(payload))

    async def consume(self, handler: Callable[[str, dict], Awaitable[None]]) -> None:
        if not self._pubsub:
            await self.connect()
        assert self._pubsub is not None
        while True:
            message = await self._pubsub.get_message(ignore_subscribe_messages=True, timeout=1.0)
            if not message:
                continue
            channel = message.get("channel")
            data = message.get("data")
            if not channel or not isinstance(data, str):
                continue
            payload = json.loads(data)
            await handler(channel, payload)