from logging.config import fileConfig

from sqlalchemy import engine_from_config
from sqlalchemy import pool

from alembic import context

import sys
import os

sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))

from app import create_app
from app.models import db

config = context.config

fileConfig(config.config_file_name)

target_metadata = db.metadata


def get_engine():
    app = create_app()
    return app.extensions["sqlalchemy"].engine


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:
    configuration = config.get_section(config.config_ini_section, {})
    configuration["sqlalchemy.url"] = os.environ.get(
        "DATABASE_URL", configuration["sqlalchemy.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()


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