import ipaddress
from rest_framework.views import APIView
from rest_framework.permissions import IsAdminUser
from rest_framework.response import Response
from django.conf import settings

from .renderers import AdminJSONRenderer
from pingcap_sso.utils.requests import get_client_ip, is_vpn_ip


class Endpoint(APIView):
    def convert_args(self, request, *args, **kwargs):
        return (args, kwargs)

    def dispatch(self, request, *args, **kwargs):
        self.args = args
        self.kwargs = kwargs
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            self.initial(request, *args, **kwargs)

            # Get the appropriate handler method
            if request.method.lower() in self.http_method_names:
                handler = getattr(self, request.method.lower(),
                                  self.http_method_not_allowed)

                (args, kwargs) = self.convert_args(request, *args, **kwargs)
                self.args = args
                self.kwargs = kwargs
            else:
                handler = self.http_method_not_allowed

            response = handler(request, *args, **kwargs)

        except Exception as exc:
            response = self.handle_exception(exc)

        self.response = self.finalize_response(
            request, response, *args, **kwargs)
        return self.response


class AdminEndpoint(Endpoint):
    renderer_classes = (AdminJSONRenderer, )
    permission_classes = (IsAdminUser, )

    def dispatch(self, request, *args, **kwargs):
        self.args = args
        self.kwargs = kwargs
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            self.initial(request, *args, **kwargs)

            # Get the appropriate handler method
            if request.method.lower() in self.http_method_names:
                handler = getattr(self, request.method.lower(),
                                  self.http_method_not_allowed)

                (args, kwargs) = self.convert_args(request, *args, **kwargs)
                self.args = args
                self.kwargs = kwargs
            else:
                handler = self.http_method_not_allowed

            if not is_vpn_ip(get_client_ip(request)):
                response = Response({
                    'error': "Please use VPN to access this API",
                }, status=403)
            else:
                response = handler(request, *args, **kwargs)

        except Exception as exc:
            response = self.handle_exception(exc)

        self.response = self.finalize_response(
            request, response, *args, **kwargs)
        return self.response


class AskTUGAdminEndpoint(Endpoint):
    renderer_classes = (AdminJSONRenderer, )
    permission_classes = (IsAdminUser, )