import os

import db_schema.base
import pytest
import sqlalchemy
from db_schema.schemas import apps, slz


@pytest.fixture(scope='session')
def engine():
    # pylint: disable=redefined-outer-name
    pg_uri = 'postgresql://{user}:{password}@{host}:{port}/{db}'.format(
        user=os.environ['PG_USER'],
        password=os.environ['PG_PASSWORD'],
        host=os.environ['PG_HOST'],
        port=os.environ['PG_PORT'],
        db=os.environ['PG_DB'],
    )
    engine = sqlalchemy.create_engine(pg_uri)
    yield engine
    engine.dispose()


@pytest.fixture(scope='function')
def session(engine):
    # pylint: disable=redefined-outer-name
    with engine.connect() as connection:
        db_schema.base.ScopedSession.configure(bind=connection)

        with connection.begin() as transaction:
            session = db_schema.base.ScopedSession()
            while True:
                result = session.execute(  # pylint: disable=no-member
                    'SELECT id FROM databasechangelog ORDER BY dateexecuted DESC LIMIT 1'
                )
                if result.first():
                    break

            cleanup_db(session)
            yield session
            db_schema.base.ScopedSession.remove()
            transaction.rollback()

        session.close()


def cleanup_db(session):
    # pylint: disable=redefined-outer-name
    for model in [
        apps.DatabricksExecution,
        apps.FailureLog,
        apps.ContentStatus,
        apps.UnitOfWork,
        apps.Report,
        slz.Report,
        slz.Licensor,
        slz.DataSource,
    ]:
        session.query(model).delete()
        session.commit()