some apis of pos

apps/warehouse/pos/api/v1/api.py

@@ -1,4 +1,5 @@
 from apps.warehouse.pos.api.v1 import serializers as warehouse_serializers
+from apps.warehouse.services.services import can_buy_from_inventory
 from apps.pos_device.mixins.pos_device_mixin import POSDeviceMixin
 from apps.core.mixins.search_mixin import DynamicSearchMixin
 from apps.warehouse import models as warehouse_models
@@ -7,6 +8,7 @@ from rest_framework.permissions import AllowAny
 from rest_framework.decorators import action
 from rest_framework.response import Response
 from rest_framework import viewsets, filters
+from apps.herd.models import Rancher
 from django.db import transaction
 from rest_framework import status
 import typing
@@ -47,6 +49,28 @@ class InventoryEntryViewSet(viewsets.ModelViewSet, DynamicSearchMixin, POSDevice
             serializer = self.get_serializer(page, many=True)
             return self.get_paginated_response(serializer.data)
 
+    @action(
+        methods=['post'],
+        detail=False,
+        url_path='rancher_inventory_entries',
+        url_name='rancher_inventory_entries',
+        name='rancher_inventory_entries'
+    )
+    @transaction.atomic
+    def rancher_inventory_entries(self, request):
+        """ """
+        organization = self.get_device_organization()
+        rancher = Rancher.objects.filter(national_code=request.data['national_code']).first()
+        entries = self.queryset.filter(organization=organization)
+
+        available_entries = [entry for entry in entries if can_buy_from_inventory(rancher, entry)]
+
+        # paginate & response
+        page = self.paginate_queryset(available_entries)
+        if page is not None:
+            serializer = self.get_serializer(page, many=True)
+            return self.get_paginated_response(serializer.data)
+
 
 class InventoryQuotaSaleTransactionViewSet(viewsets.ModelViewSet):
     queryset = warehouse_models.InventoryQuotaSaleTransaction.objects.all()

apps/warehouse/services/services.py

@@ -0,0 +1,25 @@
+from apps.warehouse.models import InventoryEntry, InventoryQuotaSaleTransaction
+from apps.herd.services.services import rancher_quota_weight
+from django.db.models import Sum
+
+
+def get_total_sold(inventory_entry, rancher):
+    """
+    """
+    return (
+            InventoryQuotaSaleTransaction.objects.filter(
+                inventory_entry=inventory_entry,
+                rancher=rancher
+            ).aggregate(total=Sum('weight'))['total'] or 0
+    )
+
+
+def can_buy_from_inventory(rancher, inventory_entry: InventoryEntry):
+    """
+    """
+    quota_weight = rancher_quota_weight(rancher, inventory_entry)  # {total, by_type}
+    total_allowed = quota_weight['total']
+
+    total_sold = get_total_sold(inventory_entry, rancher)
+
+    return total_sold < total_allowed