"""
alembic/env.py — Alembic 运行环境配置
从环境变量读取 DATABASE_URL，不硬编码。
"""

import os
from logging.config import fileConfig

from alembic import context
from sqlalchemy import engine_from_config, pool

# ── 确保 app 包可导入 ────────────────────────────────
import sys
sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))

from app.core.database import Base
import app.models  # noqa: F401 — 触发所有模型注册

config = context.config

# 从环境变量覆盖 DATABASE_URL
db_url = os.environ.get("DATABASE_URL")
if db_url:
    config.set_main_option("sqlalchemy.url", db_url)

if config.config_file_name is not None:
    fileConfig(config.config_file_name)

target_metadata = Base.metadata


def run_migrations_offline() -> None:
    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 run_migrations_online() -> None:
    connectable = engine_from_config(
        config.get_section(config.config_ini_section, {}),
        prefix="sqlalchemy.",
        poolclass=pool.NullPool,
    )
    with connectable.connect() as connection:
        context.configure(
            connection=connection,
            target_metadata=target_metadata,
        )
        with context.begin_transaction():
            context.run_migrations()


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