from __future__ import annotations
import os, sys
from logging.config import fileConfig

from sqlalchemy import engine_from_config, pool
from alembic import context

config = context.config

# Возьми URL из переменных контейнера
db_url = os.getenv("DATABASE_URL")
if db_url:
    config.set_main_option("sqlalchemy.url", db_url)

# Лог-конфиг (без падения, если секций нет)
cfg_name = config.config_file_name
if cfg_name:
    try:
        fileConfig(cfg_name)
    except Exception:
        pass

# Обеспечим PYTHONPATH=/app для импорта пакета app
ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))
if ROOT not in sys.path:
    sys.path.insert(0, ROOT)

# Метаданные моделей
from app.models.base import Base  # noqa
target_metadata = Base.metadata

def run_migrations_offline():
    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():
    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()