from django.http import HttpResponse
from rest_framework import decorators, mixins, response, status, viewsets

from apps.core.errors import error_response
from apps.orders.models import ProcessingOrder
from apps.rbac.permissions import ActionPermission
from apps.reports.models import FinalReport, ReportDefinition
from apps.reports.serializers import FinalReportSerializer, ReportDefinitionSerializer
from apps.reports.services import ReportService


class ReportDefinitionViewSet(mixins.ListModelMixin, mixins.RetrieveModelMixin, viewsets.GenericViewSet):
    queryset = ReportDefinition.objects.prefetch_related("fields").all()
    serializer_class = ReportDefinitionSerializer
    permission_classes = [ActionPermission]
    code_map = {"list": "report.view", "retrieve": "report.view"}


class FinalReportViewSet(mixins.ListModelMixin, mixins.RetrieveModelMixin, viewsets.GenericViewSet):
    queryset = FinalReport.objects.select_related("order").all()
    serializer_class = FinalReportSerializer
    permission_classes = [ActionPermission]
    code_map = {
        "list": "report.view",
        "retrieve": "report.view",
        "generate": "report.create",
        "pdf": "report.view",
    }

    def get_queryset(self):
        user = self.request.user
        qs = FinalReport.objects.select_related("order").all()
        if user.is_superuser:
            return qs
        return qs.filter(order__customer__user=user)

    @decorators.action(detail=False, methods=["post"])
    def generate(self, request):
        order_id = request.data.get("order")
        if not order_id:
            return response.Response(
                error_response("ORDER_REQUIRED", "An order id is required."),
                status=status.HTTP_400_BAD_REQUEST,
            )
        try:
            order = ProcessingOrder.objects.select_related("customer").get(pk=order_id)
        except ProcessingOrder.DoesNotExist:
            return response.Response(
                error_response("ORDER_NOT_FOUND", "Order not found."),
                status=status.HTTP_404_NOT_FOUND,
            )
        if not request.user.is_superuser and order.customer.user_id != request.user.id:
            return response.Response(
                error_response("FORBIDDEN", "You do not have access to this order."),
                status=status.HTTP_403_FORBIDDEN,
            )
        report = ReportService().generate(order)
        return response.Response(FinalReportSerializer(report).data)

    @decorators.action(detail=True, methods=["get"])
    def pdf(self, request, pk=None):
        report = self.get_object()
        pdf_bytes = ReportService().render_pdf(report)
        filename = f"{report.order.order_number}.pdf"
        return HttpResponse(
            pdf_bytes,
            content_type="application/pdf",
            headers={"Content-Disposition": f'attachment; filename="{filename}"'},
        )