from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.db.models import RoundConfig


async def get_round_config(session: AsyncSession) -> RoundConfig:
    """Single-row operational config, lazily created on first use with the
    column defaults declared on RoundConfig itself (app/db/models.py) — no env
    var involved. fee_address starts empty until an operator sets it via the
    admin panel/API — payouts must refuse to run until it's set."""
    config = await session.scalar(select(RoundConfig))
    if config is None:
        config = RoundConfig(fee_address="")
        session.add(config)
        await session.flush()
    return config