from django.shortcuts import render, redirect
from django.contrib import messages
from django.contrib.auth.decorators import login_required
from django.conf import settings
import paypalrestsdk
from .models import PayPalConfig
from products.models import Order

def setup_paypal():
    config = PayPalConfig.objects.first()
    if config:
        paypalrestsdk.configure({
            "mode": "sandbox" if config.is_sandbox else "live",
            "client_id": config.client_id,
            "client_secret": config.client_secret
        })
        return True
    return False

@login_required
def process_payment(request, order_id):
    if not setup_paypal():
        messages.error(request, 'PayPal ist nicht richtig konfiguriert. Bitte kontaktieren Sie den Administrator.')
        return redirect('order_detail', order_id=order_id)

    try:
        order = Order.objects.get(id=order_id, user=request.user)
        
        payment = paypalrestsdk.Payment({
            "intent": "sale",
            "payer": {
                "payment_method": "paypal"
            },
            "redirect_urls": {
                "return_url": request.build_absolute_uri(f'/paypal/execute/{order_id}/'),
                "cancel_url": request.build_absolute_uri(f'/paypal/cancel/{order_id}/')
            },
            "transactions": [{
                "amount": {
                    "total": str(order.total_amount),
                    "currency": "EUR"
                },
                "description": f"Bestellung #{order.id}"
            }]
        })

        if payment.create():
            for link in payment.links:
                if link.method == "REDIRECT":
                    return redirect(link.href)
        else:
            messages.error(request, 'Fehler bei der Erstellung der PayPal-Zahlung.')
            
    except Order.DoesNotExist:
        messages.error(request, 'Bestellung nicht gefunden.')
    except Exception as e:
        messages.error(request, f'Ein Fehler ist aufgetreten: {str(e)}')
    
    return redirect('order_detail', order_id=order_id)

@login_required
def execute_payment(request, order_id):
    payment_id = request.GET.get('paymentId')
    payer_id = request.GET.get('PayerID')
    
    try:
        payment = paypalrestsdk.Payment.find(payment_id)
        if payment.execute({"payer_id": payer_id}):
            order = Order.objects.get(id=order_id, user=request.user)
            order.status = 'paid'
            order.payment_method = 'paypal'
            order.payment_id = payment_id
            order.save()
            
            messages.success(request, 'Zahlung erfolgreich durchgeführt!')
            return redirect('payment_success', order_id=order_id)
        else:
            messages.error(request, 'Fehler bei der Ausführung der Zahlung.')
    except Exception as e:
        messages.error(request, f'Ein Fehler ist aufgetreten: {str(e)}')
    
    return redirect('payment_failed', order_id=order_id)

@login_required
def cancel_payment(request, order_id):
    messages.info(request, 'Die PayPal-Zahlung wurde abgebrochen.')
    return redirect('order_detail', order_id=order_id)