from collections import defaultdict from datetime import date, timedelta from decimal import Decimal from django.db.models import Sum from rest_framework.exceptions import ValidationError from rest_framework.permissions import IsAuthenticated from rest_framework.response import Response from rest_framework.views import APIView from account.permissions import HasTabPermission, get_user_shop_filter from shop_management.models.data.customer_payment import CustomerPayment from shop_management.models.data.sale import Sale from shop_management.models.data.sale_return import SaleReturn, SaleReturnItem, SaleReturnItemBatchRestoration from shop_management.models.data.shop import Shop def money(value): return str(Decimal(value or 0).quantize(Decimal("0.01"))) class SalesPerformanceReportView(APIView): permission_classes = [IsAuthenticated, HasTabPermission] required_tab = "reports" def get(self, request): try: end = date.fromisoformat(request.query_params.get("end_date") or str(date.today())) start = date.fromisoformat(request.query_params.get("start_date") or str(end - timedelta(days=29))) except ValueError: raise ValidationError({"date": "Use YYYY-MM-DD format."}) if start > end: raise ValidationError({"end_date": "End date cannot be before start date."}) shop_id = request.query_params.get("shop") if not shop_id: raise ValidationError({"shop": "Branch is required."}) try: shop = Shop.objects.get(get_user_shop_filter(request.user), pk=shop_id) except Shop.DoesNotExist: raise ValidationError({"shop": "Branch was not found or is not accessible."}) sales = list(Sale.objects.filter( shop=shop, uses_inventory_engine=True, document_status=Sale.DocumentStatus.POSTED, invoice_date__range=(start, end), ).select_related("customer", "currency").prefetch_related("sale_items__product")) sale_ids = [sale.id for sale in sales] returns = list(SaleReturn.objects.filter( sale_id__in=sale_ids, document_status=SaleReturn.DocumentStatus.POSTED, return_date__date__range=(start, end), ).select_related("sale", "sale__currency").prefetch_related("return_items__sale_item__product")) total_sales = sum((sale.calculated_total * sale.exchange_rate_used for sale in sales), Decimal("0")) total_cogs = sum((sum((item.cogs_total for item in sale.sale_items.all()), Decimal("0")) * sale.exchange_rate_used for sale in sales), Decimal("0")) total_returns = sum((row.total_refound_amount * row.sale.exchange_rate_used for row in returns), Decimal("0")) restorations = SaleReturnItemBatchRestoration.objects.filter(return_item__sale_return__in=returns).select_related("return_item__sale_return__sale", "return_item__sale_item__product") returned_cogs = sum((row.quantity * row.unit_cost * row.return_item.sale_return.sale.exchange_rate_used for row in restorations), Decimal("0")) payments = CustomerPayment.objects.filter( shop=shop, status=CustomerPayment.Status.POSTED, payment_date__range=(start, end), allocations__sale_id__in=sale_ids, ).prefetch_related("allocations").distinct() collected_base = sum((allocation.allocated_amount * payment.exchange_rate_used for payment in payments for allocation in payment.allocations.all() if allocation.sale_id in sale_ids), Decimal("0")) net_sales = total_sales - total_returns net_cogs = total_cogs - returned_cogs gross_profit = net_sales - net_cogs daily = defaultdict(lambda: {"sales": Decimal("0"), "returns": Decimal("0"), "cogs": Decimal("0")}) products = defaultdict(lambda: {"quantity": Decimal("0"), "returned_quantity": Decimal("0"), "sales": Decimal("0"), "returns": Decimal("0"), "cogs": Decimal("0"), "name": ""}) invoices = [] returned_by_sale = defaultdict(Decimal) for ret in returns: value = ret.total_refound_amount * ret.sale.exchange_rate_used daily[ret.return_date.date()]["returns"] += value returned_by_sale[ret.sale_id] += value for item in ret.return_items.all(): if item.sale_item and item.sale_item.product: row = products[item.sale_item.product_id]; row["name"] = item.sale_item.product.name row["returned_quantity"] += Decimal(item.return_quantity); row["returns"] += Decimal(item.refund_amount or 0) * ret.sale.exchange_rate_used for sale in sales: sale_rate = Decimal(sale.exchange_rate_used or 1) sale_value = sale.calculated_total * sale_rate sale_cogs_native = sum((item.cogs_total for item in sale.sale_items.all()), Decimal("0")) sale_cogs = sale_cogs_native * sale_rate daily[sale.invoice_date]["sales"] += sale_value; daily[sale.invoice_date]["cogs"] += sale_cogs ratio = sale.calculated_total / sale.calculated_subtotal if sale.calculated_subtotal else Decimal("0") allocated = sale.customer_payment_allocations.filter(payment__status=CustomerPayment.Status.POSTED, payment__payment_date__lte=end).aggregate(total=Sum("allocated_amount"))["total"] or Decimal("0") invoice_return = returned_by_sale[sale.id] invoice_return_native = invoice_return / sale_rate invoices.append({"date": sale.invoice_date, "number": sale.sale_number, "customer": sale.customer.name if sale.customer else sale.general_customer_name or "Walk-in customer", "currency": sale.currency.title, "sales_type": sale.sales_type, "total": money(sale.calculated_total), "returns": money(invoice_return_native), "cogs": money(sale_cogs_native), "collected": money(allocated), "outstanding": money(max(sale.calculated_total - allocated - invoice_return_native, Decimal("0"))), "gross_profit": money(sale.calculated_total - invoice_return_native - sale_cogs_native)}) for item in sale.sale_items.all(): if not item.product: continue row = products[item.product_id]; row["name"] = item.product.name; row["quantity"] += Decimal(item.quantity) row["sales"] += Decimal(item.quantity) * item.sale_price * ratio * sale.exchange_rate_used row["cogs"] += item.cogs_total * sale.exchange_rate_used return Response({ "shop": shop.name, "start_date": start, "end_date": end, "summary": {"gross_sales": money(total_sales), "returns": money(total_returns), "net_sales": money(net_sales), "net_cogs": money(net_cogs), "gross_profit": money(gross_profit), "gross_margin_percent": money((gross_profit / net_sales * 100) if net_sales else 0), "collected": money(collected_base), "invoice_count": len(sales)}, "daily": [{"date": day, "sales": money(row["sales"]), "returns": money(row["returns"]), "net_sales": money(row["sales"] - row["returns"]), "cogs": money(row["cogs"]), "gross_profit": money(row["sales"] - row["returns"] - row["cogs"])} for day, row in sorted(daily.items())], "products": [{"product_id": key, "product": row["name"], "quantity_sold": money(row["quantity"]), "quantity_returned": money(row["returned_quantity"]), "net_sales": money(row["sales"] - row["returns"]), "cogs": money(row["cogs"]), "gross_profit": money(row["sales"] - row["returns"] - row["cogs"])} for key, row in sorted(products.items(), key=lambda item: item[1]["sales"], reverse=True)], "invoices": invoices, })