from django.core.exceptions import PermissionDenied
from django.db.models.signals import post_save
from django.dispatch import receiver
from rest_framework.exceptions import PermissionDenied

from djeveric.signals import request_confirmation, user_confirmed, AlreadyConfirmed
from userausfall.models import User


@receiver(post_save, sender=User)
def user_saved(sender, instance: User, **kwargs):
    if (instance.confidant_unconfirmed is not None) and (instance.confidant_unconfirmed != instance.confidant):
        request_confirmation(instance.confidant_unconfirmed, instance)


@receiver(user_confirmed)
def user_confirmed(sender, user: User, instance: User, **kwargs):
    if user == instance.confidant_unconfirmed:
        if instance.confidant_unconfirmed != instance.confidant:
            # confirm the confidant
            instance.confidant = instance.confidant_unconfirmed
            instance.save()
        else:
            raise AlreadyConfirmed("The confidant has already been confirmed.")
    else:
        raise PermissionDenied()