class SignUpMixin(object):
    """
    Mixin for the common SignUp methods
    """
    permissions = []
    profile_serializer = None
    group_name = None

    def create_token(self, user):
        return Token.objects.create(user=user)

    def get_profile_data(self, profile):
        serializer = self.profile_serializer(profile)
        return serializer.data

    def assign_group(self, user):
        group = Group.objects.get(name=self.group_name)
        user.groups.add(group)

    def assign_permissions(self, user, profile):
        for permission in self.permissions:
            assign_perm(permission, user, profile)





class SignUpStudentView(SignUpMixin, GenericAPIView):
    """
    Class to register students
    """
    serializer_class = SignUpStudentSerializer
    permissions = ['students.change_student']
    profile_serializer = StudentsSerializer
    group_name = 'Students'

    def post(self, request, *args, **kwargs):
        serializer = self.get_serializer(data=request.data)

        serializer.is_valid(raise_exception=True)
        user = self.create_user(serializer)
        profile = self.create_profile(user=user)
        profile_data = self.get_profile_data(profile)
        self.assign_group(user)
        self.assign_permissions(user, profile)
        self.confirm_email_handler(user)
        token = self.create_token(user)

        #self.referral_handler(referred_id=profile.id)
        task = SendEmailSignUpCouponTask()
        task.delay(student_id=profile.id)

        return Response({'user': profile_data, 'token': token.key})

    def create_user(self, serializer):
        return User.objects.create_user(
            username=serializer.validated_data['username'],
            email=serializer.validated_data['email'],
            password=serializer.validated_data['password1'],
            first_name=serializer.validated_data['first_name'],
            last_name=serializer.validated_data['last_name'],
        )

    def create_profile(self, user):
        return Student.objects.create(user=user)

    def confirm_email_handler(self, user):
        confirm_email_token = ConfirmEmailToken.objects.create(user=user, email=user.email)
        task = SendEmailConfirmEmailTask()
        task.delay(confirm_email_token.id)