from abc import ABC, abstractmethod
from typing import Optional

from sqlalchemy.orm import scoped_session

from atlas_um.helpers.either import Either
from atlas_um.pgdb import pgdb


class BaseLogicService(ABC):
    """
    Base interface to encapsulate business logic.

    Example usage:
        class ConcreteService(BaseLogicService):
            def process(self, arg1, arg2):
                print("Doing some work")

        ConcreteService.execute(arg1, arg2)
    """

    commit: bool = True

    @classmethod
    def execute(cls, *args, **kwargs) -> Optional[Either]:
        session = pgdb.session
        instance = cls(session=session)
        result = instance.process(*args, **kwargs)
        if cls.commit:
            session.commit()
        return result

    @abstractmethod
    def process(self, *args, **kwargs) -> Optional[Either]:
        pass

    def __init__(self, session: scoped_session):
        self.session = session

    def __repr__(self):
        return self.__class__.__name__