from rest_framework import generics, status
from rest_framework.response import Response

from . import serializers
from .authentication import AUTH_HEADER_TYPES
from .exceptions import InvalidToken, TokenError


class TokenViewBase(generics.GenericAPIView):
    permission_classes = ()
    authentication_classes = ()

    serializer_class = None

    www_authenticate_realm = 'api'

    def get_authenticate_header(self, request):
        return '{0} realm="{1}"'.format(
            AUTH_HEADER_TYPES[0],
            self.www_authenticate_realm,
        )

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

        try:
            serializer.is_valid(raise_exception=True)
        except TokenError as e:
            raise InvalidToken(e.args[0])

        return Response(serializer.validated_data, status=status.HTTP_200_OK)


class TokenObtainPairView(TokenViewBase):
    """
    Takes a set of user credentials and returns an access and refresh JSON web
    token pair to prove the authentication of those credentials.
    """
    serializer_class = serializers.TokenObtainPairSerializer


token_obtain_pair = TokenObtainPairView.as_view()


class TokenRefreshView(TokenViewBase):
    """
    Takes a refresh type JSON web token and returns an access type JSON web
    token if the refresh token is valid.
    """
    serializer_class = serializers.TokenRefreshSerializer


token_refresh = TokenRefreshView.as_view()


class TokenObtainSlidingView(TokenViewBase):
    """
    Takes a set of user credentials and returns a sliding JSON web token to
    prove the authentication of those credentials.
    """
    serializer_class = serializers.TokenObtainSlidingSerializer


token_obtain_sliding = TokenObtainSlidingView.as_view()


class TokenRefreshSlidingView(TokenViewBase):
    """
    Takes a sliding JSON web token and returns a new, refreshed version if the
    token's refresh period has not expired.
    """
    serializer_class = serializers.TokenRefreshSlidingSerializer


token_refresh_sliding = TokenRefreshSlidingView.as_view()


class TokenVerifyView(TokenViewBase):
    """
    Takes a token and indicates if it is valid.  This view provides no
    information about a token's fitness for a particular use.
    """
    serializer_class = serializers.TokenVerifySerializer


token_verify = TokenVerifyView.as_view()


class TokenBlacklistView(TokenViewBase):
    """
    Takes a token and blacklists it. Must be used with the
    `rest_framework_simplejwt.token_blacklist` app installed.
    """
    serializer_class = serializers.TokenBlacklistSerializer


token_blacklist = TokenBlacklistView.as_view()