"""Shared async Redis client (sessions, rate limits, pub/sub, arq)."""

from __future__ import annotations

from collections.abc import Awaitable
from typing import Any, cast

import redis.asyncio as aioredis

from app.config import get_settings


def aw(result: Any) -> Awaitable[Any]:
    """Normalize a redis-py ``ResponseT`` (``Awaitable | value``) to an awaitable.

    Some redis-py async commands (hash ops, getdel, ...) are typed as a
    sync/async union; this keeps call sites awaitable under ``mypy --strict``.
    """
    return cast("Awaitable[Any]", result)


_client: aioredis.Redis | None = None


def get_redis() -> aioredis.Redis:
    """Return (creating on first use) the process-wide Redis client."""
    global _client
    if _client is None:
        _client = aioredis.Redis.from_url(
            get_settings().redis_url,
            encoding="utf-8",
            decode_responses=True,
        )
    return _client


async def close_redis() -> None:
    """Close the Redis client (used on app shutdown)."""
    global _client
    if _client is not None:
        await _client.aclose()
        _client = None