"""
Alembic env.py — 异步 PostgreSQL 迁移环境
从 .env 读取 DATABASE_URL，自动发现项目所有 ORM 模型
"""
import asyncio
import os
import sys
from logging.config import fileConfig

from alembic import context
from dotenv import load_dotenv
from sqlalchemy import pool
from sqlalchemy.ext.asyncio import async_engine_from_config

# 确保项目根目录在 sys.path 中
sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))

# 加载 .env
load_dotenv(os.path.join(os.path.dirname(os.path.dirname(__file__)), ".env"))

# Alembic Config
config = context.config

# 从 .env 动态设置 sqlalchemy.url（asyncpg → psycopg2 用于迁移）
db_url = os.getenv("DATABASE_URL", "")
# Alembic 需要同步驱动，将 asyncpg 替换为 psycopg2
sync_url = db_url.replace("+asyncpg", "")
config.set_main_option("sqlalchemy.url", sync_url)

# 日志配置
if config.config_file_name is not None:
    fileConfig(config.config_file_name)

# 导入所有模型，确保 Alembic 能检测到所有表
from app.models.base import Base
from app.models import crm, erp, order, shipping, finance, ai, sys as sys_models

target_metadata = Base.metadata


def run_migrations_offline() -> None:
    """离线迁移（仅生成 SQL 脚本）"""
    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)
    with context.begin_transaction():
        context.run_migrations()


async def run_async_migrations():
    """在线迁移（异步引擎）"""
    from sqlalchemy.ext.asyncio import create_async_engine

    connectable = create_async_engine(
        os.getenv("DATABASE_URL", ""),
        poolclass=pool.NullPool,
    )
    async with connectable.connect() as connection:
        await connection.run_sync(do_run_migrations)
    await connectable.dispose()


def run_migrations_online() -> None:
    """在线迁移入口"""
    # 如果是 asyncpg 则走异步迁移
    db_url = os.getenv("DATABASE_URL", "")
    if "asyncpg" in db_url:
        asyncio.run(run_async_migrations())
    else:
        from sqlalchemy import engine_from_config
        connectable = engine_from_config(
            config.get_section(config.config_ini_section, {}),
            prefix="sqlalchemy.",
            poolclass=pool.NullPool,
        )
        with connectable.connect() as connection:
            do_run_migrations(connection)


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()