import os

import pytest
import sqlalchemy
from sqlalchemy.engine import Engine
from sqlalchemy.orm import sessionmaker

from dapd_db_schema.schemas.uow_meta import AuditLog
from dapd_db_schema.schemas.uow_meta import UnitOfWork, UnitOfWorkStatusEnum


class TestSession:
    def __init__(self) -> None:
        connection_string_tpl = 'postgresql+psycopg2://{user}:{password}@{host}:{port}/{db}'
        self._workflow_engine = sqlalchemy.create_engine(
            connection_string_tpl.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_WORKFLOW_DB'],
            )
        )

        self._etl_engine = sqlalchemy.create_engine(
            connection_string_tpl.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_ETL_DB'],
            )
        )

        self._uow_meta_engine = sqlalchemy.create_engine(
            connection_string_tpl.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_ETL_DB'],
            ),
            connect_args={'options': '-csearch_path=uow_meta'}
        )

        workflow_session_cls = sessionmaker(bind=self._workflow_engine)
        self.workflow_session = workflow_session_cls(autocommit=True, autoflush=True)

        etl_session_cls = sessionmaker(bind=self._etl_engine)
        self.etl_session = etl_session_cls(autocommit=True, autoflush=True)

        uow_meta_session_cls = sessionmaker(bind=self._uow_meta_engine)
        self.uow_meta_session = uow_meta_session_cls(autocommit=True, autoflush=True)

    @property
    def etl_engine(self) -> Engine:
        return self._etl_engine

    @property
    def workflow_engine(self) -> Engine:
        return self._workflow_engine

    @property
    def uow_meta_engine(self) -> Engine:
        return self._uow_meta_engine

    def close(self) -> None:
        self._workflow_engine.dispose()
        self._etl_engine.dispose()
        self._uow_meta_engine.dispose()


@pytest.fixture(scope='session')
def db():
    test_session = TestSession()
    yield test_session
    test_session.close()


@pytest.fixture
def unit_of_work(db):
    instance = UnitOfWork(
        project='dapd',
        fact='fact_playlist_track_dynamics',
        dimensions=['dim_playlist', 'dim_track'],
        status=UnitOfWorkStatusEnum.EXPORT_IN_PROGRESS,
        version='v1',
        first_fact_id=0,
        last_fact_id=0,
    )
    db.uow_meta_session.add(instance)
    db.uow_meta_session.flush()

    yield instance

    db.uow_meta_session.query(AuditLog).filter(AuditLog.uow_id == instance.uow_id).delete()
    db.uow_meta_session.delete(instance)
    db.uow_meta_session.flush()