from abc import ABC, abstractmethod
from typing import Callable, Type, TYPE_CHECKING

from flask import Blueprint
from flask.views import View

if TYPE_CHECKING:
    from tofu_api.app import App

__all__ = [
    'BaseBlueprint',
]


class BaseBlueprint(Blueprint, ABC):
    """
    Base class for Flask blueprints.
    """

    # Reference to the application object
    app: 'App'

    @property
    @abstractmethod
    def name(self) -> str:
        """
        The name of the blueprint. Will be prepended to each endpoint name.
        """
        raise NotImplementedError

    @property
    @abstractmethod
    def import_name(self) -> str:
        """
        The name of the blueprint package. Should be set to `__name__`.
        """
        raise NotImplementedError

    @property
    @abstractmethod
    def url_prefix(self) -> str:
        """
        Prefix for all URLs.
        """
        raise NotImplementedError

    def __init__(self, app: 'App'):
        """
        Initialize blueprint. Needs the Flask application object.
        """
        super().__init__(
            name=self.name,
            import_name=self.import_name,
            url_prefix=self.url_prefix,
        )
        self.app = app
        self.init_blueprint()

    @abstractmethod
    def init_blueprint(self) -> None:
        """
        Register child blueprints and URL rules.
        """
        raise NotImplementedError

    @staticmethod
    def create_view_func(view_cls: Type[View], *args, **kwargs) -> Callable:
        """
        Helper function to create a view function from a `View` class using `view_cls.as_view()`.
        All arguments are passed to the constructor of the view class.
        """
        return view_cls.as_view(view_cls.__name__, *args, **kwargs)