from rest_framework.status import HTTP_200_OK, HTTP_201_CREATED, HTTP_400_BAD_REQUEST, HTTP_401_UNAUTHORIZED
from rest_framework.viewsets import ReadOnlyModelViewSet
from rest_framework.decorators import action
from rest_framework.response import Response
from rest_framework.permissions import IsAuthenticatedOrReadOnly, AllowAny, IsAuthenticated
from django.contrib.auth import authenticate, login, logout
from apps.users.models import User
from apps.users.serializers import UserSerializer

class UserViewSet(ReadOnlyModelViewSet):

    queryset = User.objects.all()
    serializer_class = UserSerializer
    permission_classes = [IsAuthenticatedOrReadOnly]
    lookup_field = 'uuid'

    @action(detail=False, methods=['post'], permission_classes=[AllowAny])
    def login(self, request):
        email_address = request.data.get('email_address')
        password = request.data.get('password')
        if not email_address or not password:
            return Response({'error': 'Email and password are required'}, status=HTTP_400_BAD_REQUEST)
        email_address = User.objects.normalize_email(email_address)
        user = authenticate(request, username=email_address, password=password)
        if user is None:
            return Response({'error': 'Invalid credentials'}, status=HTTP_401_UNAUTHORIZED)

        login(request, user)
        return Response({'user': UserSerializer(user).data, 'message': 'Login successful', 'success': True}, status=HTTP_200_OK)

    @action(detail=False, methods=['post'], permission_classes=[IsAuthenticated])
    def logout(self, request):
        logout(request)
        return Response({'message': 'Logout successful', 'success': True}, status=HTTP_200_OK)

    @action(detail=False, methods=['get'], permission_classes=[IsAuthenticated])
    def me(self, request):
        user_data = UserSerializer(request.user).data
        user_data['success'] = True
        return Response(user_data)

    @action(detail=False, methods=['get'], permission_classes=[AllowAny])
    def session(self, request):
        return Response({'isAuthenticated': request.user.is_authenticated, 'isStaff': request.user.is_staff if request.user.is_authenticated else False})

    @action(detail=False, methods=['post'], permission_classes=[AllowAny])
    def signup(self, request):
        try:
            data = request.data
        except:
            return Response({'detail': 'Invalid data provided.', 'success': False}, status=HTTP_400_BAD_REQUEST)
        email_address = data.get('email_address')
        if not email_address:
            return Response({'detail': 'Email address is required.', 'success': False}, status=HTTP_400_BAD_REQUEST)
        email_address = User.objects.normalize_email(email_address)
        if User.objects.filter(email_address=email_address).exists():
            return Response({'detail': 'Email address already exists.', 'success': False}, status=HTTP_400_BAD_REQUEST)

        if not data.get('first_name') or not data.get('last_name'):
            return Response({'detail': 'First and last name(s) must be provided.', 'success': False}, status=HTTP_400_BAD_REQUEST)

        if data.get('password') != data.get('confirm_password'):
            return Response({'detail': 'Passwords do not match.', 'success': False}, status=HTTP_400_BAD_REQUEST)
        try:
            user = User.objects.create_user(
                email_address=email_address,
                password=data.get('password'),
                first_name=data.get('first_name'),
                last_name=data.get('last_name'),
                date_of_birth=data.get('date_of_birth')
            )
            return Response({'detail': 'User account created successfully.', 'success': True}, status=HTTP_201_CREATED)
        except Exception as e:
            return Response({'detail': str(e), 'success': False}, status=HTTP_400_BAD_REQUEST)

    @action(detail=False, methods=['post'], permission_classes=[IsAuthenticated])
    def change_password(self, request):
        data = request.data
        required_fields = ['old_password', 'password', 'confirm_password']
        for field in required_fields:
            if not data.get(field):
                return Response({'detail': f'"{field}" not provided', 'success': False}, status=HTTP_400_BAD_REQUEST)
        if data.get('password') != data.get('confirm_password'):
            return Response({'detail': 'Passwords do not match', 'success': False}, status=HTTP_400_BAD_REQUEST)
        user = request.user
        if not user.check_password(data.get('old_password')):
            return Response({'detail': 'Old password is incorrect', 'success': False}, status=HTTP_401_UNAUTHORIZED)
        user.set_password(data.get('password'))
        user.save()
        return Response({'detail': 'Password changed successfully', 'success': True}, status=HTTP_200_OK)