from django.db import transaction
from django.utils import timezone
from rest_framework import serializers, status
from rest_framework.permissions import AllowAny, IsAuthenticated
from rest_framework.response import Response
from rest_framework.views import APIView
from rest_framework_simplejwt.exceptions import InvalidToken, TokenError
from rest_framework_simplejwt.tokens import RefreshToken

from apps.cuser.models import CUser, CuserRole, RoleType
from apps.jwt_auth.models import JwtToken, CUserRoleLoginOpt
from apps.jwt_auth.services import login_by_username, login_by_mobile, verify_mobile_and_get_token
from apps.jwt_auth.session import issue_tokens, validate_session_claims
from apps.workspace.models import Workspace


class RoleTypeSerializer(serializers.ModelSerializer):
    class Meta:
        model = RoleType
        fields = ('role_name', 'role_name_en')


class RoleSerializer(serializers.ModelSerializer):
    class WorkspaceSerializer(serializers.ModelSerializer):
        class Meta:
            model = Workspace
            fields = ('id', 'name')

    role_type = RoleTypeSerializer()
    sys_ws = WorkspaceSerializer()

    class Meta:
        model = CuserRole
        fields = ('name_family', 'title', 'role_type', 'sys_ws')


class LoginOptionSerializer(serializers.ModelSerializer):
    cuser_role = RoleSerializer()

    class Meta:
        model = CUserRoleLoginOpt
        fields = ('cuser_role', 'expire', 'uuid')


class PublicAuthView(APIView):
    authentication_classes = ()
    permission_classes = (AllowAny,)

    def get_authenticate_header(self, request):
        return 'Bearer realm="api"'


class VerifyMobileAndGetTokenView(PublicAuthView):
    class InputSerializer(serializers.Serializer):
        mobile = serializers.CharField(required=True)
        opt = serializers.IntegerField(required=True, min_value=100000, max_value=999999)

    def post(self, request):
        serializer = self.InputSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        options = verify_mobile_and_get_token(**serializer.validated_data)
        return Response(LoginOptionSerializer(options, many=True).data)


class LoginByMobileView(PublicAuthView):
    class InputSerializer(serializers.Serializer):
        mobile = serializers.CharField(required=True)

    def post(self, request):
        serializer = self.InputSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        result = login_by_mobile(**serializer.validated_data)
        return Response({'result': result}, status=202 if result['delivery_status'] == 'unconfirmed' else 200)


class LoginByUserView(PublicAuthView):
    class InputSerializer(serializers.Serializer):
        username = serializers.CharField(required=True)
        password = serializers.CharField(required=True, trim_whitespace=False, write_only=True)

    def post(self, request):
        serializer = self.InputSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        options = login_by_username(**serializer.validated_data)
        return Response(LoginOptionSerializer(options, many=True).data)


class CustomTokenObtainPairView(PublicAuthView):
    class InputSerializer(serializers.Serializer):
        uuid_opt = serializers.UUIDField(required=True)

    @transaction.atomic
    def post(self, request):
        serializer = self.InputSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        try:
            user_id = CUserRoleLoginOpt.objects.values_list('cuser_id', flat=True).get(
                uuid=serializer.validated_data['uuid_opt'], expire__gt=timezone.now())
            CUser.objects.select_for_update().get(pk=user_id)
            option = CUserRoleLoginOpt.objects.select_related(
                'cuser_role__cuser', 'cuser_role__role_type', 'cuser_role__sys_ws',
            ).get(uuid=serializer.validated_data['uuid_opt'], expire__gt=timezone.now())
        except (CUserRoleLoginOpt.DoesNotExist, CUser.DoesNotExist):
            raise InvalidToken('اعتبار درخواست ورود تمام شده است. دوباره وارد شوید.')
        if option.cuser_id != option.cuser_role.cuser_id:
            raise InvalidToken('درخواست ورود معتبر نیست.')
        data = issue_tokens(option.cuser_role)
        CUserRoleLoginOpt.objects.filter(cuser_id=option.cuser_id).delete()
        return Response(data)


class CustomTokenRefreshView(PublicAuthView):
    class InputSerializer(serializers.Serializer):
        refresh = serializers.CharField(required=True)

    @transaction.atomic
    def post(self, request):
        serializer = self.InputSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        refresh_value = serializer.validated_data['refresh']
        try:
            refresh = RefreshToken(refresh_value)
            session = JwtToken.objects.select_for_update().select_related(
                'cuser_role__cuser', 'cuser_role__role_type', 'cuser_role__sys_ws',
            ).get(refresh=refresh_value, is_blocked=False)
        except (TokenError, JwtToken.DoesNotExist):
            raise InvalidToken('نشست شما منقضی یا باطل شده است. دوباره وارد شوید.')
        validate_session_claims(session, refresh)
        return Response(issue_tokens(session.cuser_role, session=session))


class LogoutView(PublicAuthView):
    class InputSerializer(serializers.Serializer):
        refresh = serializers.CharField(required=True)

    def post(self, request):
        serializer = self.InputSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        value = serializer.validated_data['refresh']
        try:
            token = RefreshToken(value)
        except TokenError:
            return Response(status=status.HTTP_204_NO_CONTENT)
        # Possession of the signed refresh token permits logout even after access expires.
        if type(token.get('session_id')) is int and type(token.get('user_id')) is int:
            JwtToken.objects.filter(pk=token['session_id'], cuser_id=token['user_id']).update(is_blocked=True)
        else:
            JwtToken.objects.filter(refresh=value).update(is_blocked=True)
        return Response(status=status.HTTP_204_NO_CONTENT)