# Source code for django_otp.admin

    from django import forms
    from django.contrib.admin.forms import AdminAuthenticationForm
    from django.contrib.admin.sites import AdminSite

    from .forms import OTPAuthenticationFormMixin

    def _admin_template_for_django_version():
        """
        Returns the most appropriate Django login template available.

        In the past, we've had more version-specific templates. Perhaps this will
        be true again in the future. For now, the Django 1.11 version is suitable
        even with the most recent Django version.
        """
        return 'otp/admin111/login.html'

    class OTPAdminAuthenticationForm(AdminAuthenticationForm, OTPAuthenticationFormMixin):
        """
        An :class:`~django.contrib.admin.forms.AdminAuthenticationForm` subclass
        that solicits an OTP token. This has the same behavior as
        :class:`~django_otp.forms.OTPAuthenticationForm`.
        """

        otp_device = forms.CharField(required=False, widget=forms.Select)
        otp_token = forms.CharField(required=False)

        # This is a placeholder field that allows us to detect when the user clicks
        # the otp_challenge submit button.
        otp_challenge = forms.CharField(required=False)

        def clean(self):
            self.cleaned_data = super().clean()
            self.clean_otp(self.get_user())

            return self.cleaned_data

    class OTPAdminSite(AdminSite):
        """
        This is an :class:`~django.contrib.admin.AdminSite` subclass that requires
        two-factor authentication. Only users that can be verified by a registered
        OTP device will be authorized for this admin site. Unverified users will be
        treated as if :attr:`~django.contrib.auth.models.User.is_staff` is
        ``False``.
        """

        #: The default instance name of this admin site. You should instantiate
        #: this class as ``OTPAdminSite(OTPAdminSite.name)`` to make sure the admin
        #: templates render the correct URLs.
        name = 'otpadmin'

        login_form = OTPAdminAuthenticationForm

        #: We automatically select a modified login template based on your Django
        #: version. If it doesn't look right, your version may not be supported, in
        #: which case feel free to replace it.
        login_template = _admin_template_for_django_version()

        def __init__(self, name='otpadmin'):
            super().__init__(name)

        def has_permission(self, request):
            """
            In addition to the default requirements, this only allows access to
            users who have been verified by a registered OTP device.
            """
            return super().has_permission(request) and request.user.is_verified()