from logging.config import fileConfig
from flask import current_app
from alembic import context

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

target_metadata = current_app.extensions['migrate'].db.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 = current_app.extensions['migrate'].db.engine
    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()