from alembic import context
from sqlalchemy.ext.asyncio import create_async_engine
from logging.config import fileConfig

# 导入你的配置
from config import settings

# 这是 Alembic 配置对象，提供对 .ini 文件中的值的访问。
config = context.config

# 动态设置 sqlalchemy.url
config.set_main_option("sqlalchemy.url", (
        settings.DB_URL or
        '{scheme}://{user}:{password}@{host}:{port}/{db}'.format(
            scheme=settings.DB_SCHEMA,
            user=settings.DB_USER,
            password=settings.DB_PASSWORD,
            host=settings.DB_HOST,
            port=settings.DB_PORT,
            db=settings.DB_NAME,
        )
))

# 设置 target_metadata
from core.db.models import BaseModel  # 假设你的 SQLAlchemy 模型在 models.py 中

target_metadata = BaseModel.metadata


def run_migrations_offline() -> None:
    """Run migrations in 'offline' mode.

    This configures the context with just a URL
    and not an Engine, though an Engine is acceptable
    here as well.  By skipping the Engine creation
    we don't even need a DBAPI to be available.

    Calls to context.execute() here emit the given string to the
    script output.

    """
    url = config.get_main_option("sqlalchemy.url")
    context.configure(
        url=url,
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
    )

    with context.begin_transaction():
        context.run_migrations()


def do_run_migrations(connection):
    context.configure(
        connection=connection,
        target_metadata=target_metadata,
        compare_type=True,
        include_schemas=True,
    )

    with context.begin_transaction():
        context.run_migrations()


async def run_migrations_online():
    # 创建异步引擎
    connectable = create_async_engine(config.get_main_option("sqlalchemy.url"))

    async with connectable.connect() as connection:
        await connection.run_sync(do_run_migrations)


if context.is_offline_mode():
    # 离线模式（同步）
    run_migrations_offline()
else:
    import asyncio

    # 在线模式（异步）
    # 检查是否已经有事件循环
    try:
        loop = asyncio.get_event_loop()
    except RuntimeError:
        loop = asyncio.new_event_loop()
        asyncio.set_event_loop(loop)

    # 运行迁移
    loop.run_until_complete(run_migrations_online())