# management/views.py
# -*- coding: utf-8 -*-
from django.utils import timezone
from rest_framework import generics, viewsets, status
from rest_framework.response import Response
from rest_framework.permissions import IsAuthenticated, IsAdminUser
from rest_framework.views import APIView
from rest_framework_simplejwt.views import TokenObtainPairView
from rest_framework_simplejwt.tokens import RefreshToken
import datetime

from .models import (
    CustomUser, Panel, MarzbanAdmin, License, SecurityToken, Plan, Subscription,
    Payment, EndUser, PaymentMethod, PaymentSetting, PaymentDetail, TelegramUser
)
from .serializers import (
    PanelSerializer, LicenseSerializer, MarzbanAdminSerializer, CustomUserSerializer,
    SecurityTokenSerializer, PlanSerializer, SubscriptionSerializer,
    ReceiptUploadSerializer, PaymentMethodSerializer, PaymentDetailSerializer,
    EndUserPaymentDetailSerializer, AdminLevel3SubscriptionSerializer,
    PurchaseSubscriptionForUserSerializer,
)
from .tasks import (
    send_telegram_message, send_payment_receipt_to_admin,
    send_payment_confirmation_to_user,
)

# --- Authentication Views ---
class CustomTokenObtainPairView(TokenObtainPairView):
    def post(self, request, *args, **kwargs):
        response = super().post(request, *args, **kwargs)
        if response.status_code == 200:
            user = CustomUser.objects.get(username=request.data['username'])
            response.data['user_role'] = user.role
        return response

class LogoutAPIView(APIView):
    permission_classes = [IsAuthenticated]

    def post(self, request):
        try:
            refresh_token = request.data["refresh_token"]
            token = RefreshToken(refresh_token)
            token.blacklist()
            return Response({"message": "Successfully logged out."}, status=status.HTTP_200_OK)
        except Exception as e:
            return Response({"error": "Invalid token or other error."}, status=status.HTTP_400_BAD_REQUEST)

# --- ADDED: Missing ViewSets ---

class PanelViewSet(viewsets.ModelViewSet):
    serializer_class = PanelSerializer
    permission_classes = [IsAuthenticated]
    
    def get_queryset(self):
        return Panel.objects.filter(owner=self.request.user)
    
    def perform_create(self, serializer):
        serializer.save(owner=self.request.user)

class LicenseViewSet(viewsets.ModelViewSet):
    serializer_class = LicenseSerializer
    permission_classes = [IsAuthenticated]

    def get_queryset(self):
        user = self.request.user
        if user.is_super_admin():
            return License.objects.all()
        return License.objects.filter(owner=user)

class MarzbanAdminViewSet(viewsets.ModelViewSet):
    serializer_class = MarzbanAdminSerializer
    permission_classes = [IsAuthenticated]

    def get_queryset(self):
        try:
            panel = Panel.objects.get(owner=self.request.user)
            return MarzbanAdmin.objects.filter(panel=panel)
        except Panel.DoesNotExist:
            return MarzbanAdmin.objects.none()

class PlanViewSet(viewsets.ModelViewSet):
    serializer_class = PlanSerializer
    permission_classes = [IsAuthenticated]

    def get_queryset(self):
        try:
            panel = Panel.objects.get(owner=self.request.user)
            return Plan.objects.filter(panel=panel)
        except Panel.DoesNotExist:
            return Plan.objects.none()

    def perform_create(self, serializer):
        try:
            panel = Panel.objects.get(owner=self.request.user)
            serializer.save(panel=panel)
        except Panel.DoesNotExist:
            return Response({"error": "You do not own a panel."}, status=status.HTTP_403_FORBIDDEN)

class EndUserViewSet(viewsets.ModelViewSet):
    serializer_class = SubscriptionSerializer # A better serializer can be created for EndUser
    permission_classes = [IsAuthenticated]

    def get_queryset(self):
        if self.request.user.role == 'AdminLevel3':
            try:
                panel = Panel.objects.get(owner=self.request.user)
                return EndUser.objects.filter(panel=panel)
            except Panel.DoesNotExist:
                return EndUser.objects.none()
        return EndUser.objects.none()

class SubscriptionViewSet(viewsets.ModelViewSet):
    serializer_class = SubscriptionSerializer
    permission_classes = [IsAuthenticated]
    
    def get_queryset(self):
        user = self.request.user
        if user.role == 'AdminLevel3':
            try:
                panel = Panel.objects.get(owner=user)
                return Subscription.objects.filter(panel=panel)
            except Panel.DoesNotExist:
                return Subscription.objects.none()
        elif user.role == 'EndUser':
            try:
                end_user = EndUser.objects.get(username=user.username)
                return Subscription.objects.filter(end_user=end_user)
            except EndUser.DoesNotExist:
                return Subscription.objects.none()
        return Subscription.objects.none()

class PaymentViewSet(viewsets.ModelViewSet):
    serializer_class = ReceiptUploadSerializer # A better serializer can be created for listing
    permission_classes = [IsAuthenticated]

    def get_queryset(self):
        user = self.request.user
        if user.is_admin_level_3():
            return Payment.objects.filter(admin=user)
        return Payment.objects.none()
        
# --- Payment System Views ---
class PaymentMethodViewSet(viewsets.ModelViewSet):
    queryset = PaymentMethod.objects.all()
    serializer_class = PaymentMethodSerializer
    permission_classes = [IsAuthenticated]
    http_method_names = ['get', 'patch', 'put']

    def get_queryset(self):
        if self.request.user.is_authenticated and self.request.user.is_admin_level_2():
            return PaymentMethod.objects.all()
        return PaymentMethod.objects.none()

class PaymentDetailAPIView(APIView):
    permission_classes = [IsAuthenticated]

    def get(self, request):
        if not request.user.is_admin_level_3():
            return Response({'error': 'Permission denied.'}, status=status.HTTP_403_FORBIDDEN)
        details, _ = PaymentDetail.objects.get_or_create(admin_level_3=request.user)
        serializer = PaymentDetailSerializer(details)
        return Response(serializer.data)

    def put(self, request):
        if not request.user.is_admin_level_3():
            return Response({'error': 'Permission denied.'}, status=status.HTTP_403_FORBIDDEN)
        details, _ = PaymentDetail.objects.get_or_create(admin_level_3=request.user)
        serializer = PaymentDetailSerializer(details, data=request.data, partial=True)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

class EndUserPaymentOptionsAPIView(APIView):
    permission_classes = [IsAuthenticated]

    def get(self, request):
        if not request.user.role == 'EndUser':
            return Response({'error': 'Permission denied.'}, status=status.HTTP_403_FORBIDDEN)
        try:
            end_user = EndUser.objects.get(username=request.user.username)
            admin_level_3_user = end_user.panel.owner
            payment_settings = PaymentSetting.objects.filter(admin_level_3=admin_level_3_user, is_active=True)
            serializer = EndUserPaymentDetailSerializer(payment_settings, many=True)
            return Response(serializer.data)
        except EndUser.DoesNotExist:
            return Response({'error': 'User not found.'}, status=status.HTTP_404_NOT_FOUND)

# --- Subscription Management ---
class AdminLevel3SubscriptionViewSet(viewsets.ModelViewSet):
    serializer_class = AdminLevel3SubscriptionSerializer
    permission_classes = [IsAuthenticated]

    def get_queryset(self):
        if self.request.user.is_authenticated and self.request.user.role == 'AdminLevel3':
            try:
                return Subscription.objects.filter(panel__owner=self.request.user)
            except Panel.DoesNotExist:
                return Subscription.objects.none()
        return Subscription.objects.none()

    def perform_create(self, serializer):
        serializer.save()

# FIXED: Logic for purchasing subscription
class PurchaseSubscriptionForUserAPIView(APIView):
    serializer_class = PurchaseSubscriptionForUserSerializer
    permission_classes = [IsAuthenticated]

    def post(self, request, *args, **kwargs):
        serializer = self.serializer_class(data=request.data)
        serializer.is_valid(raise_exception=True)
        
        data = serializer.validated_data
        end_user_username = data.get('end_user_username')
        plan_id = data.get('plan_id')
        amount = data.get('amount')

        try:
            # The user making the request must be an EndUser
            if request.user.role != 'EndUser':
                return Response({'error': 'Only EndUsers can purchase subscriptions.'}, status=status.HTTP_403_FORBIDDEN)
            
            # Get the panel of the user making the request
            requester_end_user = EndUser.objects.get(username=request.user.username)
            panel = requester_end_user.panel
            admin_level_3_user = panel.owner

            plan = Plan.objects.get(id=plan_id, panel=panel)

            # Get or create the target end user within the same panel
            target_end_user, _ = EndUser.objects.get_or_create(
                username=end_user_username, defaults={'panel': panel}
            )

            subscription = Subscription.objects.create(
                end_user=target_end_user,
                plan=plan,
                panel=panel,
                status='pending',
            )

            payment = Payment.objects.create(
                subscription=subscription,
                admin=admin_level_3_user,
                amount=amount,
                status='pending',
            )

            return Response({
                "message": "Subscription request created successfully. Please upload the receipt.",
                "subscription_id": subscription.id,
                "payment_token": payment.payment_token
            }, status=status.HTTP_201_CREATED)

        except EndUser.DoesNotExist:
            return Response({'error': 'Requesting user profile not found.'}, status=status.HTTP_404_NOT_FOUND)
        except Plan.DoesNotExist:
            return Response({'error': 'Plan not found for your panel.'}, status=status.HTTP_404_NOT_FOUND)
        except Exception as e:
            return Response({'error': str(e)}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)

# --- Other Views ---

# ADDED: PaymentReceiptUploadAPIView (was missing)
class PaymentReceiptUploadAPIView(APIView):
    permission_classes = [IsAuthenticated]
    serializer_class = ReceiptUploadSerializer
    
    def post(self, request, *args, **kwargs):
        serializer = self.serializer_class(data=request.data)
        serializer.is_valid(raise_exception=True)
        
        try:
            payment = Payment.objects.get(payment_token=serializer.validated_data['payment_token'])
            
            # Update payment with receipt details
            payment.receipt_image = serializer.validated_data.get('receipt_image')
            payment.receipt_text = serializer.validated_data.get('receipt_text')
            payment.save()
            
            # Trigger celery task to notify admin
            send_payment_receipt_to_admin.delay(payment.id)
            
            return Response({"message": "Receipt uploaded successfully. Please wait for admin approval."}, status=status.HTTP_200_OK)
        except Payment.DoesNotExist:
            return Response({"error": "Invalid payment token."}, status=status.HTTP_404_NOT_FOUND)

# ADDED: GenerateTelegramTokenAPIView (was missing)
class GenerateTelegramTokenAPIView(APIView):
    permission_classes = [IsAuthenticated]

    def post(self, request):
        user = request.user
        expiration = timezone.now() + datetime.timedelta(minutes=5)
        # This assumes a direct relation between CustomUser and a Marzban Admin ID
        if not user.marzban_admin_id:
             return Response({'error': 'User is not linked to a Marzban admin.'}, status=status.HTTP_400_BAD_REQUEST)

        token, _ = SecurityToken.objects.update_or_create(
            admin_id=str(user.marzban_admin_id),
            defaults={'expiration_date': expiration}
        )
        return Response({'token': token.token})

class VerifyTelegramTokenAPIView(APIView):
    # This view is for unauthenticated users (the bot) to verify a token
    permission_classes = [] 

    def post(self, request):
        token_value = request.data.get('token')
        chat_id = request.data.get('chat_id')

        if not token_value or not chat_id:
            return Response({'error': 'Token and chat_id are required.'}, status=status.HTTP_400_BAD_REQUEST)

        try:
            token = SecurityToken.objects.get(token=token_value, expiration_date__gt=timezone.now())
            
            # Logic to find the main DB CustomUser and update their telegram_chat_id
            user = CustomUser.objects.get(marzban_admin_id=token.admin_id)
            
            # Assuming AdminLevel3 has a telegram_chat_id field
            if hasattr(user, 'admin_level_3'):
                user.admin_level_3.telegram_chat_id = chat_id
                user.admin_level_3.save()
            
            token.delete() # One-time use token
            return Response({'message': 'Telegram account linked successfully.'})
        except (SecurityToken.DoesNotExist, CustomUser.DoesNotExist):
            return Response({'error': 'Invalid or expired token.'}, status=status.HTTP_400_BAD_REQUEST)

class PushSubscriptionAPIView(APIView):
    permission_classes = [IsAuthenticated]
    def post(self, request, *args, **kwargs):
        # Implementation needed
        return Response({'message': 'Subscription created successfully.'})

# ADDED: TelegramWebhookView (was in urls.py but missing here)
class TelegramWebhookView(APIView):
    permission_classes = []
    
    def post(self, request, bot_token):
        # Your telegram bot logic here
        # print(request.data)
        return Response({'status': 'ok'})