"""PostgreSQL 后端集成测试（需 CHONGMING_TEST_PG_URL 环境变量，否则跳过）。"""

import os
import uuid

import asyncpg
import pytest
from sqlmodel import Field, SQLModel, select

from chongming_database import Database

PG_URL = os.environ.get("CHONGMING_TEST_PG_URL")

pytestmark = pytest.mark.skipif(
    not PG_URL, reason="CHONGMING_TEST_PG_URL 未设置，跳过 PostgreSQL 集成测试"
)


def _make_item_table(tablename: str):
    """动态生成随机表名的 SQLModel 表，避免污染共享 PG 实例。"""

    class Item(SQLModel, table=True):
        __tablename__ = tablename

        id: int | None = Field(default=None, primary_key=True)
        name: str = Field(max_length=50)

    return Item


async def test_postgres_crud():
    Item = _make_item_table(f"pg_test_item_{uuid.uuid4().hex[:8]}")
    db = Database.from_url(PG_URL)
    await db.initialize()
    try:
        async with db.get_session() as session:
            session.add(Item(name="pg"))
            await session.commit()
        async with db.get_session() as session:
            rows = (await session.execute(select(Item))).scalars().all()
            assert [r.name for r in rows] == ["pg"]
    finally:
        await db.dispose()


async def test_postgres_bare_url_scheme():
    """裸 postgresql:// 应被归一化为 postgresql+asyncpg:// 后正常连接。"""
    bare = PG_URL.replace("postgresql+asyncpg://", "postgresql://", 1)
    db = Database.from_url(bare)
    await db.initialize()
    try:
        async with db.get_session() as session:
            await session.execute(select(1))
    finally:
        await db.dispose()


async def test_from_config_postgres_end_to_end():
    db = Database.from_config({"type": "postgresql", "url": PG_URL})
    await db.initialize()
    try:
        async with db.get_session() as session:
            await session.execute(select(1))
    finally:
        await db.dispose()


async def test_postgres_generate_schemas_false():
    db = Database.from_url(PG_URL)
    await db.initialize(generate_schemas=False)
    try:
        async with db.get_session() as session:
            await session.execute(select(1))
    finally:
        await db.dispose()


async def test_postgres_auto_create_missing_database():
    """目标库不存在时 initialize() 应自动建库（回归：database "x" does not exist）。"""
    from sqlalchemy.engine import make_url

    base = make_url(PG_URL)
    db_name = f"chongming_test_autocreate_{uuid.uuid4().hex[:8]}"
    url = base.set(database=db_name).render_as_string(hide_password=False)

    db = Database.from_url(url)
    try:
        await db.initialize()  # 此前这里会因库不存在而抛 OperationalError
        async with db.get_session() as session:
            cur = await session.execute(select(1))
            assert cur.scalar() == 1
        # 幂等：库已存在时重复 initialize 也应成功（先释放旧引擎连接，便于清理）
        await db.dispose()
        await db.initialize()
    finally:
        await db.dispose()
        # 清理：连 postgres 维护库删除测试库
        maint = base.set(database="postgres")
        conn = await asyncpg.connect(
            host=maint.host,
            port=maint.port,
            user=maint.username,
            password=maint.password,
            database="postgres",
        )
        try:
            await conn.execute(f'DROP DATABASE IF EXISTS "{db_name}"')
        finally:
            await conn.close()