from __future__ import annotations

from sqlalchemy import text
from sqlalchemy.ext.asyncio import AsyncSession


async def acquire_user_credit_lock(db: AsyncSession, user_id: str) -> None:
    """PostgreSQL 事务级用户锁；SQLite 调试环境无需额外锁。"""
    bind = db.get_bind()
    dialect_name = bind.dialect.name if bind is not None else ""
    if dialect_name == "postgresql":
        await db.execute(
            text("SELECT pg_advisory_xact_lock(hashtextextended(:lock_key, 0))"),
            {"lock_key": f"credit:{user_id}"},
        )