from django.contrib.auth import get_user_model

from courses.models import Course
from lms.global_decorators import transaction_decorator
from rest_framework.views import APIView
from rest_framework.renderers import JSONRenderer
from rest_framework.response import Response
from django.db.models import Q
from django.shortcuts import redirect
import csv
from django.http import HttpResponse, HttpResponseForbidden

from yandex_money.models import Payment
from finance.models import Bill, Invoice
from finance.serializers import BillSerializer, InvoiceSerializer
from lms.tools import get_real_name
import requests


class BillListView(APIView):
    renderer_classes = (JSONRenderer,)

    @staticmethod
    def get(request):
        if request.user.is_authenticated:
            return Response(
                [BillSerializer(i).data for i in Bill.objects.filter(Q(user=request.user) | Q(opener=request.user))],
                status=200,
            )
        return Response("Permission denied", status=403)

    @transaction_decorator
    def post(self, request):
        if request.user.is_authenticated and (request.user.groups.filter(name__in=['managers','lead_managers']).exists()
                                              or request.user.is_superuser):
            bill = request.JSON.get('bill')
            children = request.JSON.get('children', [])

            if bill:
                bill['user'] = get_user_model().objects.get(email=bill['user'])
                bill['opener'] = get_user_model().objects.get(email=bill['opener'])
                bill['course'] = Course.objects.get(title=bill['course'][0])
                bill_obj, is_create = Bill.objects.update_or_create(**bill)
                invoices = bill_obj.invoice_set.all()

                for i in children:
                    i['method'] = get_real_name(elem=i['method'][0], array=Invoice.BILL_METHOD)
                    i['status'] = get_real_name(elem=i['status'][0], array=Invoice.BILL_STATUSES)
                    i['bill'] = bill_obj
                    i['yandex_pay'] = None
                    invoice, _is_create = Invoice.objects.update_or_create(**i)
                    if i['method'] == 'Y':
                        yandex_pay, _is_create = Payment.objects.get_or_create(
                            order_amount=i['price'],
                            order_number=invoice.id,
                            customer_number=bill_obj.user.id,
                            user=bill_obj.user,
                            cps_email=bill_obj.user.email,
                        )
                        invoice.yandex_pay = yandex_pay
                        invoice.save()

                    invoices = [j for j in invoices if not j.id == invoice.id]

                [i.delete() for i in invoices]

                res = {
                    "bill": BillSerializer(bill_obj).data,
                    "children": [InvoiceSerializer(i).data for i in bill_obj.invoice_set.all()],
                }

                return Response(res, status=200)

            return Response("Bill not set", status=400)

        return Response("Course detail access only for manager users", status=403)


class BillDetailView(APIView):
    renderer_classes = (JSONRenderer,)
    status_code = 200

    def get(self, request, pk):
        if request.user.is_authenticated:
            try:
                bill = Bill.objects.get(id=pk)
            except Bill.DoesNotExist:
                return Response("Bill not found", status=404)

            res = {
                "bill": BillSerializer(bill).data,
                "children": [InvoiceSerializer(i).data for i in bill.invoice_set.all()],
            }

            return Response(
                res,
                status=self.status_code,
            )
        return Response("Permission denied", status=403)


class YandexPay(APIView):
    renderer_classes = (JSONRenderer,)

    @staticmethod
    def get(request, pk):
        try:
            pay = Payment.objects.get(id=pk)
            r = requests.post('https://money.yandex.ru/eshop.xml', data={
                'shopId': pay.shop_id,
                'scid': pay.scid,
                'sum': pay.order_amount,
                'customerNumber': pay.customer_number,
                'orderNumber': pay.order_number,
                'cps_email': pay.cps_email,
            })
            return redirect(r.url)

        except Payment.DoesNotExist:
            return Response('Payment not found', status=404)


def get_invoices(request):
    if not request.user.is_authenticated and (request.user.groups.filter(name="finance") or request.user.is_superuser):
        return HttpResponseForbidden()

    date_from = request.GET.get('from', None)
    date_to = request.GET.get('to', None)

    file_name = "invoices"
    file_name = file_name + "__from_%s" % date_from if date_from else file_name
    file_name = file_name + "__to_%s" % date_to if date_to else file_name

    invoices = Invoice.objects.filter(method="Y", status="F")
    invoices = invoices.filter(date__lt=date_to) if date_to else invoices
    invoices = invoices.filter(date__gte=date_from) if date_from else invoices

    response = HttpResponse(content_type='text/csv')
    response['Content-Disposition'] = 'attachment; filename="%s"' % file_name

    writer = csv.writer(response)
    writer.writerow(['date', 'student_email', 'full_name', 'course', 'price', 'real_price', 'key'])

    for i in invoices.order_by('-date'):
        writer.writerow([
            i.date,
            i.bill.user.email,
            i.bill.user.get_full_name(),
            i.bill.course.title,
            i.price,
            i.real_price,
            i.key,
        ])

    return response