from .models import User
from rest_framework import status
from rest_framework.response import Response
from rest_framework.generics import CreateAPIView,UpdateAPIView
from rest_framework.authtoken.models import Token
from rest_framework.views import APIView
from django.contrib.auth import authenticate
from drf_yasg.utils import swagger_auto_schema
from drf_yasg import openapi
from django.utils.http import urlsafe_base64_decode
from django.utils.encoding import force_str

from .serializers import ForgotPasswordSerializer, ResetPasswordSerializer, UserRegistrationSerializer
from django.contrib.auth.tokens import default_token_generator


class UserRegistrationAPIView(CreateAPIView):
    serializer_class = UserRegistrationSerializer
    def post(self, request, format=None):
        serializer = UserRegistrationSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)



class LoginView(APIView):
    @swagger_auto_schema(
        request_body=openapi.Schema(
            type=openapi.TYPE_OBJECT,
            required=['email', 'password'],
            properties={
                'email': openapi.Schema(type=openapi.TYPE_STRING),
                'password': openapi.Schema(type=openapi.TYPE_STRING),
            },
        ),
        responses={
            status.HTTP_200_OK: openapi.Schema(
                type=openapi.TYPE_OBJECT,
                properties={
                    'token': openapi.Schema(type=openapi.TYPE_STRING),
                },
            ),
        },
    )
    def post(self, request):
        email = request.data.get('email')
        password = request.data.get('password')

        if email is None or password is None:
            return Response({'error': 'Please provide both email and password'}, status=status.HTTP_400_BAD_REQUEST)

        user = authenticate(email=email, password=password)

        if not user:
            return Response({'error': 'Invalid credentials'}, status=status.HTTP_401_UNAUTHORIZED)

        token, _ = Token.objects.get_or_create(user=user)

        return Response({'token': token.key})


class ResetPasswordView(CreateAPIView):
    serializer_class = ForgotPasswordSerializer

    def post(self, request):
        serializer = self.serializer_class(data=request.data)
        if serializer.is_valid():
            email = serializer.validated_data.get("email")
            if User.objects.filter(email=email).exists():
                user = User.objects.get(email=email)
                scheme = "https" if request.is_secure() else "http"
                full_host = request.get_host()
                base_url = f"{scheme}://{full_host}"
                user.send_forgot_password_email(base_url, email)
                return Response({"message": "Password reset email sent"})
            else:
                return Response({"error": "Email does not exist"}, status=status.HTTP_400_BAD_REQUEST)
        else:
            return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
        

class ChangePasswordView(UpdateAPIView):
    serializer_class = ResetPasswordSerializer
    http_method_names = ['patch', 'head', 'options', 'trace'] 

    def partial_update(self, request, *args, **kwargs):
        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)

        uid = force_str(urlsafe_base64_decode(serializer.validated_data['uid']))
        user = User.objects.get(pk=uid)

        if user is not None and default_token_generator.check_token(user, serializer.validated_data['token']):
            user.set_password(serializer.validated_data['new_password'])
            user.save()
            return Response({"message": "Password updated successfully"}, status=status.HTTP_200_OK)
        else:
            return Response({"error": "Invalid token or user does not exist"}, status=status.HTTP_400_BAD_REQUEST)