from __future__ import annotations

import os
from logging.config import fileConfig

from alembic import context
from sqlalchemy import engine_from_config, pool

from cloud.database import normalize_database_url
from cloud.db_models import Base


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

target_metadata = Base.metadata


def _database_url() -> str:
    return normalize_database_url(
        os.environ.get("CLOUD_DATABASE_URL") or config.get_main_option("sqlalchemy.url")
    )


def run_migrations_offline() -> None:
    context.configure(
        url=_database_url(),
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
    )
    with context.begin_transaction():
        context.run_migrations()


def run_migrations_online() -> None:
    supplied_connection = config.attributes.get("connection")
    if supplied_connection is not None:
        context.configure(
            connection=supplied_connection, target_metadata=target_metadata
        )
        with context.begin_transaction():
            context.run_migrations()
        return

    configuration = config.get_section(config.config_ini_section) or {}
    configuration["sqlalchemy.url"] = _database_url()
    connectable = engine_from_config(
        configuration,
        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()
    connectable.dispose()


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