"""Optional real PostgreSQL acceptance; never reuse or reset an existing business DB."""

import asyncio
import os
import subprocess
from pathlib import Path
from uuid import uuid4

import asyncpg
import pytest
from sqlalchemy.engine import make_url


@pytest.fixture
def postgres_url():
    admin = os.environ.get("KF_OJ_TEST_POSTGRES")
    if admin is None:
        pytest.skip("real PostgreSQL acceptance requires KF_OJ_TEST_POSTGRES")
    url = make_url(admin)
    database = "kf_oj_test_" + uuid4().hex
    assert url.drivername == "postgresql+asyncpg"
    test_url = url.set(database=database).render_as_string(hide_password=False)

    async def manage(command):
        connection = await asyncpg.connect(
            url.set(drivername="postgresql").render_as_string(hide_password=False)
        )
        try:
            await connection.execute(command)
        finally:
            await connection.close()

    asyncio.run(manage(f'CREATE DATABASE "{database}"'))
    try:
        migrate(test_url, "upgrade", "head")
        yield test_url
    finally:
        asyncio.run(manage(f'DROP DATABASE "{database}"'))


def migrate(url: str, command: str, target: str | None = None) -> None:
    subprocess.run(
        [str(Path(__file__).resolve().parents[1] / ".venv/bin/alembic"), command]
        + ([target] if target else []),
        cwd=Path(__file__).resolve().parents[1],
        env=os.environ | {"KF_OJ_DATABASE_URL": url},
        check=True,
        capture_output=True,
    )


async def connect(url: str):
    return await asyncpg.connect(url.replace("postgresql+asyncpg:", "postgresql:", 1))