"""arq queue helpers (enqueue side, used by the API)."""

from __future__ import annotations

from arq import create_pool
from arq.connections import ArqRedis, RedisSettings

from app.config import get_settings

_pool: ArqRedis | None = None


def redis_settings() -> RedisSettings:
    """Return arq RedisSettings derived from ``REDIS_URL``."""
    return RedisSettings.from_dsn(get_settings().redis_url)


async def get_arq_pool() -> ArqRedis:
    """Return (creating on first use) the shared arq enqueue pool."""
    global _pool
    if _pool is None:
        _pool = await create_pool(redis_settings())
    return _pool


async def close_arq_pool() -> None:
    """Close the arq pool."""
    global _pool
    if _pool is not None:
        await _pool.aclose()
        _pool = None