added net weight, user, date etc. generates new document number with year as a prefix, restarts numbering every year

backend/api/views.py

@@ -2,7 +2,7 @@ from rest_framework import viewsets, status
 from rest_framework.decorators import action
 from rest_framework.response import Response
 from rest_framework.permissions import IsAuthenticated, AllowAny
-from .models import ComPortReading, User, Report
+from .models import ComPortReading, User, Report, generate_doc_number
 from .serializers import (
     ComPortReadingSerializer, UserSerializer, UserDetailSerializer,
     ChangePasswordSerializer, VehicleSerializer, NomenclatureSerializer,
@@ -111,6 +111,16 @@ class ComPortReadingViewSet(viewsets.ModelViewSet):
         serializer.save(source_ip=self.get_client_ip(self.request))
 
 
+def _maybe_finalize(vehicle, user):
+    """If both tare and gross are set and net hasn't been calculated yet, compute net and assign doc_number."""
+    if vehicle.tare is not None and vehicle.gross is not None and vehicle.net is None:
+        vehicle.net = vehicle.gross - vehicle.tare
+        vehicle.net_date = timezone.now()
+        vehicle.net_user = user
+        vehicle.doc_number = generate_doc_number(timezone.now().year)
+        vehicle.save()
+
+
 class VehicleViewSet(viewsets.ModelViewSet):
     """
     API endpoint for vehicle management.
@@ -183,6 +193,7 @@ class VehicleViewSet(viewsets.ModelViewSet):
         vehicle.tare_date = timezone.now()
         vehicle.tare_user = request.user
         vehicle.save()
+        _maybe_finalize(vehicle, request.user)
 
         serializer = self.get_serializer(vehicle)
         sse_broadcast_update('vehicle', 'updated', serializer.data)
@@ -204,6 +215,7 @@ class VehicleViewSet(viewsets.ModelViewSet):
         vehicle.gross_date = timezone.now()
         vehicle.gross_user = request.user
         vehicle.save()
+        _maybe_finalize(vehicle, request.user)
 
         serializer = self.get_serializer(vehicle)
         sse_broadcast_update('vehicle', 'updated', serializer.data)