"""
This module defines mixins for gnuviechadmin views.

"""
from __future__ import unicode_literals

from django.http import HttpResponseForbidden
from django.utils.translation import ugettext as _

from braces.views import LoginRequiredMixin


class StaffOrSelfLoginRequiredMixin(LoginRequiredMixin):
    """
    Mixin that makes sure that a user is logged in and matches the current
    customer or is a staff user.

    """

    def dispatch(self, request, *args, **kwargs):
        if (
            request.user.is_staff or
            request.user == self.get_customer_object()
        ):
            return super(StaffOrSelfLoginRequiredMixin, self).dispatch(
                request, *args, **kwargs
            )
        return HttpResponseForbidden(
            _('You are not allowed to view this page.')
        )

    def get_customer_object(self):
        """
        Views based on this mixin have to implement this method to return
        the customer that must be an object of the same class as the
        django.contrib.auth user type.

        :return: customer
        :rtype: settings.AUTH_USER_MODEL

        """
        raise NotImplemented("subclass has to implement get_customer_object")