from typing import List
from django.contrib.auth.mixins import UserPassesTestMixin

from django.contrib.auth.models import User
from django.db import models

class SuperuserRequiredMixin(UserPassesTestMixin):
    def test_func(self):
        return self.request.user.is_superuser

class CheckCanEditMixin():
    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)

        context["can_edit"] = self.object.check_user_can_edit(self.request.user)

        return context
    


class QuestionMixin():

    def get_app_name(self):
        raise NotImplementedError("You must implement get_app_name in the derived class")

    def get_base_template(self):
        return f"{self.get_app_name()}/base.html"

    def get_link_headers(self):
        return f"{self.get_app_name()}/question_link_header.html"

class AuthorMixin():
    """Mixin class for models that have authors
    
    requires an author many to many field to be defined on the derived class
    
    """
    author = models.ManyToManyField(User)  # Corrected typing

    def get_author_objects(self) -> List[User]:  # Updated type hint
        """Returns list of author objects"""
        authors = [i for i in self.author.all()]
        return authors

    def get_authors(self):
        """Returns a comma separated text list of authors as usernames.

        """
        authors = ", ".join([i.username for i in self.author.all()])
        if not authors:
            return "None"
        return authors

    def add_author(self, user: User):
        """Add an author to the object"""
        self.author.add(user)

    def remove_author(self, user: User):
        """Remove an author from the object"""
        self.author.remove(user)