feat: added pre sales order in business module, and explode tests of business module

business/tests/fixtures.py

@@ -0,0 +1,98 @@
+from basic_info import models as basic_models
+
+
+def create_basic_fixtures():
+    merchant = basic_models.Merchant.objects.create(
+        name='测试商户',
+        type=basic_models.MerchantTypeEnum.FACTORY,
+    )
+    basic_models.MerchantSetting.objects.create(
+        merchant=merchant,
+        key=basic_models.MerchantSettingKeyEnum.AUTO_CREATE_STOCK_CHANGE_TASKS,
+        type=basic_models.MerchantSettingTypeEnum.BOOL,
+        val_bool=True,
+    )
+    supplier = basic_models.Supplier.objects.create(
+        merchant=merchant,
+        name='测试供应商',
+    )
+    warehouse_strict = basic_models.WareHouse.objects.create(
+        merchant=merchant,
+        name='严进仓',
+        mode=basic_models.WareHouseModeEnum.RESTRICT_IN,
+    )
+    warehouse_relaxed = basic_models.WareHouse.objects.create(
+        merchant=merchant,
+        name='宽进仓',
+        mode=basic_models.WareHouseModeEnum.UNRESTRICTED,
+    )
+    category = basic_models.ProductCategory.objects.create(
+        merchant=merchant,
+        name='面料',
+        product_prefix='FAB',
+    )
+    product = basic_models.Product.objects.create(
+        merchant=merchant,
+        category=category,
+        name='测试面料',
+        human_id='FAB-001',
+        unit=basic_models.ProductUnitEnum.METER,
+    )
+    operator = basic_models.Employee.objects.create(
+        merchant=merchant,
+        name='经办人',
+        status=basic_models.EmployeeStatusEnum.ACTIVE,
+    )
+    return merchant, supplier, warehouse_strict, warehouse_relaxed, product, operator
+
+
+def create_sales_fixtures():
+    merchant = basic_models.Merchant.objects.create(
+        name='销售商户',
+        type=basic_models.MerchantTypeEnum.FACTORY,
+    )
+    basic_models.MerchantSetting.objects.create(
+        merchant=merchant,
+        key=basic_models.MerchantSettingKeyEnum.AUTO_CREATE_STOCK_CHANGE_TASKS,
+        type=basic_models.MerchantSettingTypeEnum.BOOL,
+        val_bool=True,
+    )
+    customer = basic_models.Customer.objects.create(
+        merchant=merchant,
+        name='客户A',
+        mobile='13800000000',
+        created_by=None,
+    )
+    warehouse_strict = basic_models.WareHouse.objects.create(
+        merchant=merchant,
+        name='销售严进仓',
+        mode=basic_models.WareHouseModeEnum.RESTRICT_IN,
+    )
+    warehouse_relaxed = basic_models.WareHouse.objects.create(
+        merchant=merchant,
+        name='销售宽进仓',
+        mode=basic_models.WareHouseModeEnum.UNRESTRICTED,
+    )
+    warehouse_strict_out = basic_models.WareHouse.objects.create(
+        merchant=merchant,
+        name='销售严出仓',
+        mode=basic_models.WareHouseModeEnum.RESTRICT_IN_OUT,
+    )
+    category = basic_models.ProductCategory.objects.create(
+        merchant=merchant,
+        name='销售品类',
+        product_prefix='SAL',
+    )
+    product = basic_models.Product.objects.create(
+        merchant=merchant,
+        category=category,
+        name='销售面料',
+        human_id='SAL-001',
+        unit=basic_models.ProductUnitEnum.METER,
+    )
+    operator = basic_models.Employee.objects.create(
+        merchant=merchant,
+        name='销售员',
+        status=basic_models.EmployeeStatusEnum.ACTIVE,
+    )
+    return merchant, customer, warehouse_strict, warehouse_relaxed, warehouse_strict_out, product, operator

business/tests/test_concurrency.py

@@ -0,0 +1,76 @@
+from concurrent.futures import ThreadPoolExecutor
+
+from django.contrib.auth import get_user_model
+from django.db import close_old_connections, connections
+from django.test import TransactionTestCase
+from django.utils import timezone
+
+from basic_info import models as basic_models
+from business import models as business_models, services
+
+from .fixtures import create_sales_fixtures
+
+
+class SalesOrderConcurrencyTestCase(TransactionTestCase):
+    reset_sequences = True
+
+    def setUp(self):
+        (
+            self.merchant,
+            self.customer,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.warehouse_strict_out,
+            self.product,
+            self.operator,
+        ) = create_sales_fixtures()
+        basic_models.MerchantSetting.objects.filter(
+            merchant=self.merchant,
+            key=basic_models.MerchantSettingKeyEnum.AUTO_CREATE_STOCK_CHANGE_TASKS,
+        ).update(val_bool=False)
+        User = get_user_model()
+        self.user = User.objects.create_user(username='concurrent', password='pass123')
+        self.sales_order = services.create_sales_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'numbers': [5], 'price': '12', 'unit': '米'}],
+            created_by=self.user,
+        )
+
+    def test_concurrent_sales_order_approval_updates_balance_once(self):
+        def approve():
+            # ThreadPoolExecutor 会复用线程；Django 的 DB connection 是线程局部的，
+            # 若不显式关闭，可能导致测试 DB 在 teardown 时仍被占用，无法 DROP。
+            close_old_connections()
+            try:
+                services.review_sales_order(
+                    sales_order_id=self.sales_order.id,
+                    target_status=business_models.SalesOrderStatusEnum.APPROVED,
+                    reviewed_by=self.user,
+                )
+            finally:
+                connections.close_all()
+
+        with ThreadPoolExecutor(max_workers=2) as executor:
+            futures = [executor.submit(approve) for _ in range(2)]
+            for future in futures:
+                future.result()
+
+        balance = business_models.CustomerBalance.objects.get(
+            merchant=self.merchant,
+            customer=self.customer,
+        )
+        self.assertEqual(balance.balance, self.sales_order.get_total_amount())
+        records = business_models.BalanceChangeRecord.objects.filter(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.SALES_ORDER,
+            source_id=self.sales_order.id,
+        )
+        self.assertEqual(records.count(), 1)
+        self.assertEqual(records.first().balance_after, balance.balance)
+
+    def tearDown(self):
+        connections.close_all()

business/tests/test_payment_receipt.py

@@ -0,0 +1,249 @@
+from decimal import Decimal
+
+from django.test import TestCase
+from django.utils import timezone
+
+from basic_info import models as basic_models
+from business import models as business_models, services
+
+from .fixtures import create_basic_fixtures
+
+
+class PaymentReceiptServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.supplier,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.product,
+            self.operator,
+        ) = create_basic_fixtures()
+        self.customer = basic_models.Customer.objects.create(
+            merchant=self.merchant,
+            name='客户B',
+            mobile='13888888888',
+            created_by=None,
+        )
+        self.bank_account = basic_models.BankAccount.objects.create(
+            merchant=self.merchant,
+            name='测试账户',
+            auto_number='BANK-SVC',
+        )
+
+    def test_create_payment_order_and_approve(self):
+        order = services.create_payment_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            payment_date=timezone.now().date(),
+            amount='120.50',
+            discount_amount='20.50',
+            operator=self.operator,
+            remarks='付款测试',
+            bank_account=self.bank_account,
+            markup='服务层附言',
+        )
+        self.assertEqual(order.status, business_models.PaymentOrderStatusEnum.PENDING)
+        self.assertEqual(order.bank_account, self.bank_account)
+        self.assertEqual(order.markup, '服务层附言')
+        self.assertEqual(order.discount_amount, Decimal('20.50'))
+        self.assertEqual(order.settlement_amount, Decimal('141.00'))
+        reviewed = services.review_payment_order(
+            payment_order=order,
+            target_status=business_models.PaymentOrderStatusEnum.APPROVED,
+            reviewed_by=self.operator,
+        )
+        self.assertEqual(reviewed.status, business_models.PaymentOrderStatusEnum.APPROVED)
+        balance = business_models.SupplierBalance.objects.get(
+            merchant=self.merchant,
+            supplier=self.supplier,
+        )
+        self.assertEqual(balance.balance, Decimal('-141.00'))
+        record = business_models.BalanceChangeRecord.objects.get(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.PAYMENT_ORDER,
+            source_id=order.id,
+        )
+        self.assertEqual(record.direction, business_models.BalanceChangeDirectionEnum.DECREASE)
+        self.assertEqual(record.delta, Decimal('-141.00'))
+        self.assertEqual(record.balance_after, balance.balance)
+        with self.assertRaises(ValueError):
+            services.review_payment_order(
+                payment_order=order,
+                target_status=business_models.PaymentOrderStatusEnum.CANCELLED,
+                reviewed_by=self.operator,
+            )
+
+    def test_create_receipt_order_and_cancel(self):
+        order = services.create_receipt_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            receipt_date=timezone.now().date(),
+            amount='80.00',
+            discount_amount='5',
+            operator=self.operator,
+            remarks='收款测试',
+            bank_account=self.bank_account,
+            markup='收款附言',
+        )
+        self.assertEqual(order.bank_account, self.bank_account)
+        self.assertEqual(order.discount_amount, Decimal('5'))
+        self.assertEqual(order.settlement_amount, Decimal('85'))
+        cancelled = services.review_receipt_order(
+            receipt_order=order,
+            target_status=business_models.ReceiptOrderStatusEnum.CANCELLED,
+            reviewed_by=self.operator,
+        )
+        self.assertEqual(cancelled.status, business_models.ReceiptOrderStatusEnum.CANCELLED)
+        self.assertFalse(
+            business_models.BalanceChangeRecord.objects.filter(
+                merchant=self.merchant,
+                source_type=business_models.BalanceChangeSourceEnum.RECEIPT_ORDER,
+                source_id=order.id,
+            ).exists()
+        )
+
+    def test_payment_amount_can_be_negative(self):
+        order = services.create_payment_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            payment_date=timezone.now().date(),
+            amount='-25.50',
+            operator=self.operator,
+        )
+        self.assertEqual(order.amount, Decimal('-25.50'))
+
+    def test_payment_discount_can_exceed_amount(self):
+        order = services.create_payment_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            payment_date=timezone.now().date(),
+            amount='50',
+            discount_amount='60',
+            operator=self.operator,
+        )
+        self.assertEqual(order.settlement_amount, Decimal('110'))
+
+    def test_receipt_discount_can_exceed_amount(self):
+        order = services.create_receipt_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            receipt_date=timezone.now().date(),
+            amount='50',
+            discount_amount='60',
+            operator=self.operator,
+        )
+        self.assertEqual(order.settlement_amount, Decimal('110'))
+
+    def test_receipt_amount_can_be_negative(self):
+        order = services.create_receipt_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            receipt_date=timezone.now().date(),
+            amount='-40',
+            operator=self.operator,
+        )
+        self.assertEqual(order.amount, Decimal('-40'))
+
+    def test_payment_order_rejects_foreign_bank_account(self):
+        other_merchant = basic_models.Merchant.objects.create(
+            name='无关商户',
+            type=basic_models.MerchantTypeEnum.FACTORY,
+        )
+        foreign_bank = basic_models.BankAccount.objects.create(
+            merchant=other_merchant,
+            name='其他账户',
+            auto_number='BANK-FOREIGN',
+        )
+        with self.assertRaises(ValueError):
+            services.create_payment_order(
+                merchant=self.merchant,
+                supplier=self.supplier,
+                payment_date=timezone.now().date(),
+                amount='10',
+                operator=self.operator,
+                bank_account=foreign_bank,
+            )
+
+    def test_receipt_order_rejects_foreign_bank_account(self):
+        other_merchant = basic_models.Merchant.objects.create(
+            name='第二商户',
+            type=basic_models.MerchantTypeEnum.FACTORY,
+        )
+        foreign_bank = basic_models.BankAccount.objects.create(
+            merchant=other_merchant,
+            name='第二账户',
+            auto_number='BANK-SECOND',
+        )
+        with self.assertRaises(ValueError):
+            services.create_receipt_order(
+                merchant=self.merchant,
+                customer=self.customer,
+                receipt_date=timezone.now().date(),
+                amount='10',
+                operator=self.operator,
+                bank_account=foreign_bank,
+            )
+
+    def test_receipt_approval_is_idempotent(self):
+        order = services.create_receipt_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            receipt_date=timezone.now().date(),
+            amount='10',
+            operator=self.operator,
+        )
+        services.review_receipt_order(
+            receipt_order=order,
+            target_status=business_models.ReceiptOrderStatusEnum.APPROVED,
+            reviewed_by=self.operator,
+        )
+        reviewed_again = services.review_receipt_order(
+            receipt_order=order,
+            target_status=business_models.ReceiptOrderStatusEnum.APPROVED,
+            reviewed_by=self.operator,
+        )
+        self.assertEqual(reviewed_again.status, business_models.ReceiptOrderStatusEnum.APPROVED)
+        balance = business_models.CustomerBalance.objects.get(
+            merchant=self.merchant,
+            customer=self.customer,
+        )
+        self.assertEqual(balance.balance, Decimal('-10'))
+        records = business_models.BalanceChangeRecord.objects.filter(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.RECEIPT_ORDER,
+            source_id=order.id,
+        )
+        self.assertEqual(records.count(), 1)
+        self.assertEqual(records.first().balance_after, balance.balance)
+
+    def test_payment_approval_is_idempotent(self):
+        order = services.create_payment_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            payment_date=timezone.now().date(),
+            amount='75.00',
+            operator=self.operator,
+        )
+        services.review_payment_order(
+            payment_order=order,
+            target_status=business_models.PaymentOrderStatusEnum.APPROVED,
+            reviewed_by=self.operator,
+        )
+        services.review_payment_order(
+            payment_order=order,
+            target_status=business_models.PaymentOrderStatusEnum.APPROVED,
+            reviewed_by=self.operator,
+        )
+        balance = business_models.SupplierBalance.objects.get(
+            merchant=self.merchant,
+            supplier=self.supplier,
+        )
+        self.assertEqual(balance.balance, Decimal('-75.00'))
+        records = business_models.BalanceChangeRecord.objects.filter(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.PAYMENT_ORDER,
+            source_id=order.id,
+        )
+        self.assertEqual(records.count(), 1)
+        self.assertEqual(records.first().balance_after, balance.balance)

business/tests/test_pre_sales_order.py

@@ -0,0 +1,112 @@
+from django.test import TestCase
+
+from basic_info import models as basic_models
+from business import models as business_models
+from business import pre_order_services
+
+from .fixtures import create_sales_fixtures
+
+
+class PreSalesOrderServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.customer,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.warehouse_strict_out,
+            self.product,
+            self.operator,
+        ) = create_sales_fixtures()
+
+    def test_create_pre_sales_order_success(self):
+        pre_sales_order = pre_order_services.create_pre_sales_order(
+            merchant=self.merchant,
+            customer_id=self.customer.id,
+            warehouse_id=self.warehouse_relaxed.id,
+            created_by=self.operator,
+            kind=business_models.SalesOrderKindEnum.WHOLESALE,
+            items=[
+                {
+                    'product_id': self.product.id,
+                    'quantity': '12.5',
+                    'unit': '米',
+                    'order_quantity': 8,
+                    'remarks': 'item-remarks',
+                }
+            ],
+            remarks='order-remarks',
+        )
+
+        self.assertEqual(pre_sales_order.merchant_id, self.merchant.id)
+        self.assertEqual(pre_sales_order.customer_id, self.customer.id)
+        self.assertEqual(pre_sales_order.warehouse_id, self.warehouse_relaxed.id)
+        self.assertEqual(pre_sales_order.created_by_id, self.operator.id)
+        self.assertEqual(pre_sales_order.items.count(), 1)
+
+        item = pre_sales_order.items.first()
+        self.assertEqual(item.product_id, self.product.id)
+        self.assertEqual(item.unit, '米')
+        self.assertEqual(item.order_quantity, 8)
+
+    def test_create_pre_sales_order_rejects_cross_merchant_customer(self):
+        other_merchant = basic_models.Merchant.objects.create(
+            name='其他商户',
+            type=basic_models.MerchantTypeEnum.FACTORY,
+        )
+        other_customer = basic_models.Customer.objects.create(
+            merchant=other_merchant,
+            name='其他客户',
+            created_by=None,
+        )
+
+        with self.assertRaises(ValueError):
+            pre_order_services.create_pre_sales_order(
+                merchant=self.merchant,
+                customer_id=other_customer.id,
+                warehouse_id=self.warehouse_relaxed.id,
+                created_by=self.operator,
+                items=[{'product_id': self.product.id, 'quantity': '1', 'unit': '米'}],
+            )
+
+    def test_update_pre_sales_order_replaces_items(self):
+        pre_sales_order = pre_order_services.create_pre_sales_order(
+            merchant=self.merchant,
+            customer_id=self.customer.id,
+            warehouse_id=self.warehouse_relaxed.id,
+            created_by=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': '10', 'unit': '米'}],
+        )
+
+        updated = pre_order_services.update_pre_sales_order(
+            pre_sales_order=pre_sales_order,
+            warehouse_id=self.warehouse_strict.id,
+            items=[
+                {
+                    'product_id': self.product.id,
+                    'quantity': '20',
+                    'unit': '米',
+                    'order_quantity': 3,
+                }
+            ],
+            remarks='updated-remarks',
+        )
+
+        self.assertEqual(updated.warehouse_id, self.warehouse_strict.id)
+        self.assertEqual(updated.remarks, 'updated-remarks')
+        self.assertEqual(updated.items.count(), 1)
+        self.assertEqual(str(updated.items.first().quantity), '20.00')
+        self.assertEqual(updated.items.first().order_quantity, 3)
+
+    def test_delete_pre_sales_order(self):
+        pre_sales_order = pre_order_services.create_pre_sales_order(
+            merchant=self.merchant,
+            customer_id=self.customer.id,
+            warehouse_id=self.warehouse_relaxed.id,
+            created_by=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': '10', 'unit': '米'}],
+        )
+        order_id = pre_sales_order.id
+
+        pre_order_services.delete_pre_sales_order(pre_sales_order=pre_sales_order)
+        self.assertFalse(business_models.PreSalesOrder.objects.filter(id=order_id).exists())

business/tests/test_purchase_order.py

@@ -0,0 +1,265 @@
+from typing import Any, Dict, List
+from decimal import Decimal
+
+from django.contrib.auth import get_user_model
+from django.test import TestCase
+from django.utils import timezone
+from unittest.mock import patch
+
+from stock import models as stock_models
+from business import models as business_models, services
+
+from .fixtures import create_basic_fixtures
+
+
+class PurchaseOrderServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.supplier,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.product,
+            self.operator,
+        ) = create_basic_fixtures()
+        User = get_user_model()
+        self.user = User.objects.create_user(username='creator', password='pass123')
+        self.strict_items: List[Dict[str, Any]] = [
+            {'product_id': self.product.id, 'numbers': [10, 5], 'price': '12.5', 'unit': '米'}
+        ]
+        self.relaxed_items: List[Dict[str, Any]] = [
+            {'product_id': self.product.id, 'quantity': 120, 'num_of_rolls': 3, 'price': '10.0', 'unit': '米'}
+        ]
+
+    def test_create_purchase_order_does_not_trigger_task_immediately(self):
+        with patch('business.services.create_purchase_order_stock_entries.delay') as mock_delay:
+            purchase_order = services.create_purchase_order(
+                merchant=self.merchant,
+                supplier=self.supplier,
+                order_date=timezone.now().date(),
+                warehouse=self.warehouse_strict,
+                operator=self.operator,
+                items=self.strict_items,
+                remarks='自动化测试',
+                created_by=self.user,
+            )
+
+        self.assertIsInstance(purchase_order, business_models.PurchaseOrder)
+        self.assertEqual(purchase_order.status, business_models.PurchaseOrderStatusEnum.PENDING)
+        self.assertEqual(purchase_order.items.count(), 1)
+        item = purchase_order.items.first()
+        self.assertEqual(item.quantity_of_rolls, '10,5')
+        self.assertEqual(item.split_quantity_of_rolls(), [10, 5])
+        mock_delay.assert_not_called()
+
+    def test_purchase_order_human_id_generation(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        self.assertIsNotNone(purchase_order.human_id)
+        self.assertEqual(
+            purchase_order.human_id,
+            f"CG{purchase_order.created_at.strftime('%Y%m%d')}{purchase_order.id:06d}",
+        )
+
+    def test_review_purchase_order_approval_triggers_task(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+
+        with patch('business.services.create_purchase_order_stock_entries.delay') as mock_delay:
+            reviewed = services.review_purchase_order(
+                purchase_order=purchase_order,
+                target_status=business_models.PurchaseOrderStatusEnum.APPROVED,
+                reviewed_by=self.user,
+            )
+
+        self.assertEqual(reviewed.status, business_models.PurchaseOrderStatusEnum.APPROVED)
+        mock_delay.assert_called_once_with(
+            purchase_order_id=purchase_order.id,
+            warehouse_id=self.warehouse_strict.id,
+            items=[{'product_id': self.product.id, 'quantities': ['10', '5']}],
+            created_by_id=self.user.id,
+        )
+        balance = business_models.SupplierBalance.objects.get(
+            merchant=self.merchant,
+            supplier=self.supplier,
+        )
+        self.assertEqual(balance.balance, purchase_order.get_total_amount())
+        record = business_models.BalanceChangeRecord.objects.get(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.PURCHASE_ORDER,
+            source_id=purchase_order.id,
+        )
+        self.assertEqual(record.target_type, business_models.BalanceChangeTargetEnum.SUPPLIER)
+        self.assertEqual(record.delta, purchase_order.get_total_amount())
+        self.assertEqual(record.balance_after, balance.balance)
+        self.assertEqual(record.direction, business_models.BalanceChangeDirectionEnum.INCREASE)
+
+    def test_create_purchase_order_without_items_raises(self):
+        with self.assertRaises(ValueError):
+            services.create_purchase_order(
+                merchant=self.merchant,
+                supplier=self.supplier,
+                order_date=timezone.now().date(),
+                warehouse=self.warehouse_strict,
+                operator=self.operator,
+                items=[],
+            )
+
+    def test_review_purchase_order_cancel_without_stock(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=self.relaxed_items,
+            created_by=self.user,
+        )
+        item = purchase_order.items.first()
+        self.assertIsNone(item.quantity_of_rolls)
+        self.assertEqual(item.split_quantity_of_rolls(), [])
+
+        cancelled = services.review_purchase_order(
+            purchase_order=purchase_order,
+            target_status=business_models.PurchaseOrderStatusEnum.CANCELLED,
+            reviewed_by=self.user,
+        )
+        self.assertEqual(cancelled.status, business_models.PurchaseOrderStatusEnum.CANCELLED)
+        self.assertFalse(
+            business_models.BalanceChangeRecord.objects.filter(
+                merchant=self.merchant,
+                source_type=business_models.BalanceChangeSourceEnum.PURCHASE_ORDER,
+                source_id=purchase_order.id,
+            ).exists()
+        )
+
+    def test_review_purchase_order_cancel_blocked_after_stock_created(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=self.relaxed_items,
+            created_by=self.user,
+        )
+        stock_models.StockChangeRecord.objects.create(
+            merchant=self.merchant,
+            type=stock_models.StockChangeTypeEnum.ADD,
+            warehouse=self.warehouse_relaxed,
+            source_type=stock_models.StockChangeSourceEnum.PURCHASE,
+            source_id=purchase_order.id,
+        )
+
+        with self.assertRaises(ValueError):
+            services.review_purchase_order(
+                purchase_order=purchase_order,
+                target_status=business_models.PurchaseOrderStatusEnum.CANCELLED,
+                reviewed_by=self.user,
+            )
+
+    def test_review_purchase_order_relaxed_mode_approval_payload(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=self.relaxed_items,
+            created_by=self.user,
+        )
+
+        with patch('business.services.create_purchase_order_stock_entries.delay') as mock_delay:
+            services.review_purchase_order(
+                purchase_order=purchase_order,
+                target_status=business_models.PurchaseOrderStatusEnum.APPROVED,
+                reviewed_by=self.user,
+            )
+
+        mock_delay.assert_called_once_with(
+            purchase_order_id=purchase_order.id,
+            warehouse_id=self.warehouse_relaxed.id,
+            items=[{'product_id': self.product.id, 'value': '120.00', 'num_of_rolls': 3}],
+            created_by_id=self.user.id,
+        )
+
+    def test_update_purchase_order_success(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=self.relaxed_items,
+            created_by=self.user,
+        )
+        updated = services.update_purchase_order(
+            purchase_order=purchase_order,
+            warehouse=self.warehouse_strict,
+            items=self.strict_items,
+            remarks='updated',
+        )
+        self.assertEqual(updated.remarks, 'updated')
+        self.assertEqual(updated.items.count(), 1)
+        self.assertEqual(updated.items.first().split_quantity_of_rolls(), [10, 5])
+
+    def test_update_purchase_order_rejects_non_pending(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=self.relaxed_items,
+            created_by=self.user,
+        )
+        purchase_order.status = business_models.PurchaseOrderStatusEnum.APPROVED
+        purchase_order.save(update_fields=['status'])
+        with self.assertRaises(ValueError):
+            services.update_purchase_order(
+                purchase_order=purchase_order,
+                items=self.relaxed_items,
+            )
+
+    def test_purchase_order_relaxed_mode_even_split(self):
+        purchase_order = services.create_purchase_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[
+                {
+                    'product_id': self.product.id,
+                    'quantity': 99,
+                    'num_of_rolls': 2,
+                    'price': '10.0',
+                    'unit': '米',
+                }
+            ],
+            created_by=self.user,
+        )
+        stock_flow_items = services._build_stock_flow_items_from_order(purchase_order)
+        payload = services.create_purchase_order_stock_entries_sync(
+            purchase_order_id=purchase_order.id,
+            warehouse_id=self.warehouse_relaxed.id,
+            items=stock_flow_items,
+            created_by_id=self.user.id,
+        )
+        record = stock_models.StockChangeRecord.objects.get(id=payload['stock_change_record_id'])
+        quantities = sorted([detail.quantity for detail in record.details.order_by('id')], reverse=True)
+        self.assertEqual(quantities, [Decimal('49.50'), Decimal('49.50')])

business/tests/test_purchase_return.py

@@ -0,0 +1,183 @@
+from decimal import Decimal
+
+from django.contrib.auth import get_user_model
+from django.test import TestCase
+from django.utils import timezone
+from unittest.mock import patch
+
+from basic_info import models as basic_models
+from stock import models as stock_models
+from business import models as business_models, services
+
+from .fixtures import create_basic_fixtures
+
+
+class PurchaseReturnServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.supplier,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.product,
+            self.operator,
+        ) = create_basic_fixtures()
+        self.warehouse_strict_out = basic_models.WareHouse.objects.create(
+            merchant=self.merchant,
+            name='采退严出仓',
+            mode=basic_models.WareHouseModeEnum.RESTRICT_IN_OUT,
+        )
+        User = get_user_model()
+        self.user = User.objects.create_user(username='purchase-return', password='pass123')
+        self.strict_items = [
+            {'product_id': self.product.id, 'numbers': [4, 2], 'price': '11.5', 'unit': '米'}
+        ]
+        self.strict_out_items = [
+            {
+                'product_id': self.product.id,
+                'consume_detail_ids': [10, 11],
+                'quantity': 30,
+                'price': '12.0',
+                'unit': '米',
+            }
+        ]
+
+    def test_create_purchase_return_order_success(self):
+        order = services.create_purchase_return_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        self.assertEqual(order.status, business_models.PurchaseReturnStatusEnum.PENDING)
+        self.assertEqual(order.items.count(), 1)
+        item = order.items.first()
+        self.assertEqual(item.quantity_of_rolls, '4,2')
+        self.assertEqual(item.split_quantity_of_rolls(), [4, 2])
+
+    def test_purchase_return_order_human_id_generation(self):
+        order = services.create_purchase_return_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        self.assertIsNotNone(order.human_id)
+        self.assertEqual(
+            order.human_id,
+            f"CT{order.created_at.strftime('%Y%m%d')}{order.id:06d}",
+        )
+
+    def test_review_purchase_return_order_triggers_task_and_balance(self):
+        order = services.create_purchase_return_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': 40, 'num_of_rolls': 2, 'price': '10.0'}],
+            created_by=self.user,
+        )
+        with patch('business.services.create_purchase_return_order_stock_entries.delay') as mock_delay:
+            reviewed = services.review_purchase_return_order(
+                purchase_return_order=order,
+                target_status=business_models.PurchaseReturnStatusEnum.APPROVED,
+                reviewed_by=self.user,
+            )
+        self.assertEqual(reviewed.status, business_models.PurchaseReturnStatusEnum.APPROVED)
+        mock_delay.assert_called_once()
+        balance = business_models.SupplierBalance.objects.get(
+            merchant=self.merchant,
+            supplier=self.supplier,
+        )
+        self.assertEqual(balance.balance, Decimal('-400.00'))
+        record = business_models.BalanceChangeRecord.objects.get(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.PURCHASE_RETURN_ORDER,
+            source_id=order.id,
+        )
+        self.assertEqual(record.direction, business_models.BalanceChangeDirectionEnum.DECREASE)
+
+    def test_purchase_return_cancel_blocked_after_stock_created(self):
+        order = services.create_purchase_return_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': 20, 'num_of_rolls': 2, 'price': '9.5'}],
+        )
+        stock_models.StockChangeRecord.objects.create(
+            merchant=self.merchant,
+            type=stock_models.StockChangeTypeEnum.REMOVE,
+            warehouse=self.warehouse_relaxed,
+            source_type=stock_models.StockChangeSourceEnum.PURCHASE_RETURN,
+            source_id=order.id,
+        )
+        with self.assertRaises(ValueError):
+            services.review_purchase_return_order(
+                purchase_return_order=order,
+                target_status=business_models.PurchaseReturnStatusEnum.CANCELLED,
+            )
+
+    def test_purchase_return_strict_out_requires_consume_ids(self):
+        payload = [
+            {
+                'product_id': self.product.id,
+                'quantity': 10,
+                'price': '8.5',
+                'unit': '米',
+            }
+        ]
+        with self.assertRaises(ValueError):
+            services.create_purchase_return_order(
+                merchant=self.merchant,
+                supplier=self.supplier,
+                return_date=timezone.now().date(),
+                warehouse=self.warehouse_strict_out,
+                operator=self.operator,
+                items=payload,
+            )
+
+    def test_update_purchase_return_order_success(self):
+        order = services.create_purchase_return_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        updated = services.update_purchase_return_order(
+            purchase_return_order=order,
+            items=self.strict_items,
+            remarks='updated',
+        )
+        self.assertEqual(updated.remarks, 'updated')
+        self.assertEqual(updated.items.count(), 1)
+        self.assertEqual(updated.items.first().split_quantity_of_rolls(), [4, 2])
+
+    def test_update_purchase_return_order_rejects_non_pending(self):
+        order = services.create_purchase_return_order(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        order.status = business_models.PurchaseReturnStatusEnum.APPROVED
+        order.save(update_fields=['status'])
+        with self.assertRaises(ValueError):
+            services.update_purchase_return_order(
+                purchase_return_order=order,
+                items=self.strict_items,
+            )

business/tests/test_sales_order.py

@@ -0,0 +1,231 @@
+from django.contrib.auth import get_user_model
+from django.test import TestCase
+from django.utils import timezone
+from unittest.mock import patch
+
+from stock import models as stock_models
+from business import models as business_models, services
+
+from .fixtures import create_sales_fixtures
+
+
+class SalesOrderServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.customer,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.warehouse_strict_out,
+            self.product,
+            self.operator,
+        ) = create_sales_fixtures()
+        User = get_user_model()
+        self.user = User.objects.create_user(username='sales-creator', password='pass123')
+        self.strict_items = [
+            {'product_id': self.product.id, 'numbers': [6, 4], 'price': '30.5', 'unit': '米'}
+        ]
+        self.relaxed_items = [
+            {'product_id': self.product.id, 'quantity': 80, 'num_of_rolls': 2, 'price': '28.0', 'unit': '米'}
+        ]
+        self.strict_out_items = [
+            {
+                'product_id': self.product.id,
+                'consume_detail_ids': [1, 2],
+                'quantity': 40,
+                'price': '32.0',
+                'unit': '米',
+            }
+        ]
+
+    def test_create_sales_order_success(self):
+        with patch('business.services.create_sales_order_stock_entries.delay') as mock_delay:
+            sales_order = services.create_sales_order(
+                merchant=self.merchant,
+                customer=self.customer,
+                order_date=timezone.now().date(),
+                warehouse=self.warehouse_strict,
+                operator=self.operator,
+                items=self.strict_items,
+                remarks='销售测试',
+                created_by=self.user,
+            )
+
+        self.assertIsInstance(sales_order, business_models.SalesOrder)
+        self.assertEqual(sales_order.status, business_models.SalesOrderStatusEnum.PENDING)
+        self.assertEqual(sales_order.items.count(), 1)
+        item = sales_order.items.first()
+        self.assertEqual(item.quantity_of_rolls, '6,4')
+        self.assertEqual(item.split_quantity_of_rolls(), [6, 4])
+        mock_delay.assert_not_called()
+
+    def test_sales_order_human_id_generation(self):
+        sales_order = services.create_sales_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+
+        self.assertIsNotNone(sales_order.human_id)
+        self.assertTrue(len(sales_order.human_id) >= 14)
+        self.assertEqual(
+            sales_order.human_id,
+            f"XS{sales_order.created_at.strftime('%Y%m%d')}{sales_order.id:06d}",
+        )
+
+    def test_review_sales_order_triggers_task(self):
+        sales_order = services.create_sales_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        with patch('business.services.create_sales_order_stock_entries.delay') as mock_delay:
+            reviewed = services.review_sales_order(
+                sales_order=sales_order,
+                target_status=business_models.SalesOrderStatusEnum.APPROVED,
+                reviewed_by=self.user,
+            )
+        self.assertEqual(reviewed.status, business_models.SalesOrderStatusEnum.APPROVED)
+        mock_delay.assert_called_once_with(
+            sales_order_id=sales_order.id,
+            warehouse_id=self.warehouse_strict.id,
+            items=[{'product_id': self.product.id, 'quantities': ['6', '4']}],
+            created_by_id=self.user.id,
+        )
+        balance = business_models.CustomerBalance.objects.get(
+            merchant=self.merchant,
+            customer=self.customer,
+        )
+        self.assertEqual(balance.balance, sales_order.get_total_amount())
+        record = business_models.BalanceChangeRecord.objects.get(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.SALES_ORDER,
+            source_id=sales_order.id,
+        )
+        self.assertEqual(record.target_type, business_models.BalanceChangeTargetEnum.CUSTOMER)
+        self.assertEqual(record.delta, sales_order.get_total_amount())
+        self.assertEqual(record.balance_after, balance.balance)
+        self.assertEqual(record.direction, business_models.BalanceChangeDirectionEnum.INCREASE)
+
+    def test_sales_order_cancel_blocked_after_stock_created(self):
+        sales_order = services.create_sales_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=self.relaxed_items,
+            created_by=self.user,
+        )
+        stock_models.StockChangeRecord.objects.create(
+            merchant=self.merchant,
+            type=stock_models.StockChangeTypeEnum.REMOVE,
+            warehouse=self.warehouse_relaxed,
+            source_type=stock_models.StockChangeSourceEnum.SALES,
+            source_id=sales_order.id,
+        )
+        with self.assertRaises(ValueError):
+            services.review_sales_order(
+                sales_order=sales_order,
+                target_status=business_models.SalesOrderStatusEnum.CANCELLED,
+                reviewed_by=self.user,
+            )
+        self.assertFalse(
+            business_models.BalanceChangeRecord.objects.filter(
+                merchant=self.merchant,
+                source_type=business_models.BalanceChangeSourceEnum.SALES_ORDER,
+                source_id=sales_order.id,
+            ).exists()
+        )
+
+    def test_sales_order_requires_consume_ids_for_strict_out(self):
+        with self.assertRaises(ValueError):
+            services.create_sales_order(
+                merchant=self.merchant,
+                customer=self.customer,
+                order_date=timezone.now().date(),
+                warehouse=self.warehouse_strict_out,
+                operator=self.operator,
+                items=[{'product_id': self.product.id, 'quantity': 10, 'price': '20', 'unit': '米'}],
+                created_by=self.user,
+            )
+
+    def test_sales_order_stores_consume_ids(self):
+        sales_order = services.create_sales_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict_out,
+            operator=self.operator,
+            items=self.strict_out_items,
+            created_by=self.user,
+        )
+        item = sales_order.items.first()
+        self.assertEqual(item.consume_detail_ids, '1,2')
+
+    def test_sales_order_outgoing_missing_consume_ids_raises(self):
+        payload = [
+            {
+                'product_id': self.product.id,
+                'quantity': 30,
+                'price': '25',
+                'unit': '米',
+            }
+        ]
+        with self.assertRaises(ValueError):
+            services.create_sales_order(
+                merchant=self.merchant,
+                customer=self.customer,
+                order_date=timezone.now().date(),
+                warehouse=self.warehouse_strict_out,
+                operator=self.operator,
+                items=payload,
+                created_by=self.user,
+            )
+
+    def test_update_sales_order_success(self):
+        sales_order = services.create_sales_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        updated = services.update_sales_order(
+            sales_order=sales_order,
+            warehouse=self.warehouse_relaxed,
+            items=self.relaxed_items,
+            remarks='updated',
+        )
+        self.assertEqual(updated.remarks, 'updated')
+        self.assertEqual(updated.items.count(), 1)
+        item = updated.items.first()
+        self.assertEqual(item.split_quantity_of_rolls(), [])
+
+    def test_update_sales_order_rejects_non_pending(self):
+        sales_order = services.create_sales_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            order_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        sales_order.status = business_models.SalesOrderStatusEnum.APPROVED
+        sales_order.save(update_fields=['status'])
+        with self.assertRaises(ValueError):
+            services.update_sales_order(
+                sales_order=sales_order,
+                items=self.strict_items,
+            )

business/tests/test_sales_return.py

@@ -0,0 +1,182 @@
+from decimal import Decimal
+
+from django.contrib.auth import get_user_model
+from django.test import TestCase
+from django.utils import timezone
+from unittest.mock import patch
+
+from stock import models as stock_models
+from business import models as business_models, services
+
+from .fixtures import create_sales_fixtures
+
+
+class SalesReturnServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.customer,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.warehouse_strict_out,
+            self.product,
+            self.operator,
+        ) = create_sales_fixtures()
+        User = get_user_model()
+        self.user = User.objects.create_user(username='sales-return', password='pass123')
+        self.strict_items = [
+            {'product_id': self.product.id, 'numbers': [6, 2], 'price': '20.0', 'unit': '米'}
+        ]
+
+    def test_create_sales_return_order_success(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': 50, 'num_of_rolls': 2, 'price': '19.5'}],
+        )
+        self.assertEqual(order.status, business_models.SalesReturnStatusEnum.PENDING)
+        item = order.items.first()
+        self.assertEqual(item.split_quantity_of_rolls(), [])
+
+    def test_sales_return_order_human_id_generation(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': 50, 'num_of_rolls': 2, 'price': '19.5'}],
+            created_by=self.user,
+        )
+        self.assertIsNotNone(order.human_id)
+        self.assertEqual(
+            order.human_id,
+            f"XT{order.created_at.strftime('%Y%m%d')}{order.id:06d}",
+        )
+
+    def test_review_sales_return_order_updates_balance(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        self.assertEqual(order.items.first().split_quantity_of_rolls(), [6, 2])
+        with patch('business.services.create_sales_return_order_stock_entries.delay') as mock_delay:
+            reviewed = services.review_sales_return_order(
+                sales_return_order=order,
+                target_status=business_models.SalesReturnStatusEnum.APPROVED,
+                reviewed_by=self.user,
+            )
+        self.assertEqual(reviewed.status, business_models.SalesReturnStatusEnum.APPROVED)
+        mock_delay.assert_called_once()
+        balance = business_models.CustomerBalance.objects.get(
+            merchant=self.merchant,
+            customer=self.customer,
+        )
+        self.assertLess(balance.balance, Decimal('0'))
+        record = business_models.BalanceChangeRecord.objects.get(
+            merchant=self.merchant,
+            source_type=business_models.BalanceChangeSourceEnum.SALES_RETURN_ORDER,
+            source_id=order.id,
+        )
+        self.assertEqual(record.direction, business_models.BalanceChangeDirectionEnum.DECREASE)
+
+    def test_sales_return_cancel_blocked_after_stock_created(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': 15, 'num_of_rolls': 1, 'price': '18.0'}],
+        )
+        stock_models.StockChangeRecord.objects.create(
+            merchant=self.merchant,
+            type=stock_models.StockChangeTypeEnum.ADD,
+            warehouse=self.warehouse_relaxed,
+            source_type=stock_models.StockChangeSourceEnum.SALES_RETURN,
+            source_id=order.id,
+        )
+        with self.assertRaises(ValueError):
+            services.review_sales_return_order(
+                sales_return_order=order,
+                target_status=business_models.SalesReturnStatusEnum.CANCELLED,
+            )
+
+    def test_sales_return_relaxed_mode_stock_payload_preserves_rolls(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': 100, 'num_of_rolls': 1, 'price': '22.0'}],
+        )
+        stock_flow_items = services._build_stock_flow_items_from_order(order)
+        self.assertEqual(len(stock_flow_items), 1)
+        self.assertEqual(stock_flow_items[0]['num_of_rolls'], 1)
+
+    def test_sales_return_relaxed_mode_even_split(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_relaxed,
+            operator=self.operator,
+            items=[{'product_id': self.product.id, 'quantity': 100, 'num_of_rolls': 3, 'price': '22.0'}],
+            created_by=self.user,
+        )
+        stock_flow_items = services._build_stock_flow_items_from_order(order)
+        payload = services.create_sales_return_order_stock_entries_sync(
+            sales_return_order_id=order.id,
+            warehouse_id=self.warehouse_relaxed.id,
+            items=stock_flow_items,
+            created_by_id=self.user.id,
+        )
+        record = stock_models.StockChangeRecord.objects.get(id=payload['stock_change_record_id'])
+        quantities = sorted([detail.quantity for detail in record.details.order_by('id')], reverse=True)
+        self.assertEqual(quantities, [Decimal('33.34'), Decimal('33.33'), Decimal('33.33')])
+
+    def test_update_sales_return_order_success(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        updated = services.update_sales_return_order(
+            sales_return_order=order,
+            items=self.strict_items,
+            remarks='updated',
+        )
+        self.assertEqual(updated.remarks, 'updated')
+        self.assertEqual(updated.items.count(), 1)
+        self.assertEqual(updated.items.first().split_quantity_of_rolls(), [6, 2])
+
+    def test_update_sales_return_order_rejects_non_pending(self):
+        order = services.create_sales_return_order(
+            merchant=self.merchant,
+            customer=self.customer,
+            return_date=timezone.now().date(),
+            warehouse=self.warehouse_strict,
+            operator=self.operator,
+            items=self.strict_items,
+            created_by=self.user,
+        )
+        order.status = business_models.SalesReturnStatusEnum.APPROVED
+        order.save(update_fields=['status'])
+        with self.assertRaises(ValueError):
+            services.update_sales_return_order(
+                sales_return_order=order,
+                items=self.strict_items,
+            )

business/tests/test_stock_services.py

@@ -0,0 +1,128 @@
+from django.contrib.auth import get_user_model
+from django.test import TestCase
+from django.utils import timezone
+from unittest.mock import patch, MagicMock
+
+from stock import models as stock_models
+from business import models as business_models, services
+
+from .fixtures import create_basic_fixtures, create_sales_fixtures
+
+
+class PurchaseOrderStockServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.supplier,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.product,
+            self.operator,
+        ) = create_basic_fixtures()
+        User = get_user_model()
+        self.user = User.objects.create_user(username='svc-user', password='pass123')
+        self.purchase_order = business_models.PurchaseOrder.objects.create(
+            merchant=self.merchant,
+            supplier=self.supplier,
+            purchase_date=timezone.now().date(),
+            operator=self.operator,
+            warehouse=self.warehouse_strict,
+        )
+        self.items = [{'product_id': self.product.id, 'quantities': ['8']}]
+
+    def test_service_calls_stock_flow_service(self):
+        with patch('business.services.StockFlowService') as mock_flow_cls:
+            mock_instance = mock_flow_cls.return_value
+            mock_instance.stock_in.return_value = (MagicMock(id=321), [], 2)
+
+            payload = services.create_purchase_order_stock_entries_sync(
+                purchase_order_id=self.purchase_order.id,
+                warehouse_id=self.warehouse_strict.id,
+                items=self.items,
+                created_by_id=self.user.id,
+            )
+
+        mock_flow_cls.assert_called_once_with(merchant=self.merchant, created_by=self.user)
+        mock_instance.stock_in.assert_called_once_with(
+            warehouse_id=self.warehouse_strict.id,
+            source_type=stock_models.StockChangeSourceEnum.PURCHASE,
+            source_id=self.purchase_order.id,
+            items=[{'product_id': self.product.id, 'quantities': ['8']}],
+        )
+        self.assertEqual(payload['purchase_order_id'], self.purchase_order.id)
+        self.assertEqual(payload['stock_change_record_id'], 321)
+
+
+class SalesOrderStockServiceTestCase(TestCase):
+    def setUp(self):
+        (
+            self.merchant,
+            self.customer,
+            self.warehouse_strict,
+            self.warehouse_relaxed,
+            self.warehouse_strict_out,
+            self.product,
+            self.operator,
+        ) = create_sales_fixtures()
+        User = get_user_model()
+        self.user = User.objects.create_user(username='sales-svc', password='pass123')
+        self.sales_order = business_models.SalesOrder.objects.create(
+            merchant=self.merchant,
+            customer=self.customer,
+            sales_date=timezone.now().date(),
+            operator=self.operator,
+            warehouse=self.warehouse_strict,
+        )
+        self.items = [{'product_id': self.product.id, 'quantities': ['5']}]
+
+    def test_service_calls_stock_out(self):
+        with patch('business.services.StockFlowService') as mock_flow_cls:
+            mock_instance = mock_flow_cls.return_value
+            mock_instance.stock_out.return_value = (MagicMock(id=654), [], 1)
+
+            payload = services.create_sales_order_stock_entries_sync(
+                sales_order_id=self.sales_order.id,
+                warehouse_id=self.warehouse_strict.id,
+                items=self.items,
+                created_by_id=self.user.id,
+            )
+
+        mock_flow_cls.assert_called_once_with(merchant=self.merchant, created_by=self.user)
+        mock_instance.stock_out.assert_called_once_with(
+            warehouse_id=self.warehouse_strict.id,
+            source_type=stock_models.StockChangeSourceEnum.SALES,
+            source_id=self.sales_order.id,
+            items=[{'product_id': self.product.id, 'quantities': ['5']}],
+        )
+        self.assertEqual(payload['sales_order_id'], self.sales_order.id)
+        self.assertEqual(payload['stock_change_record_id'], 654)
+
+    def test_service_calls_stock_out_strict_mode(self):
+        strict_order = business_models.SalesOrder.objects.create(
+            merchant=self.merchant,
+            customer=self.customer,
+            sales_date=timezone.now().date(),
+            operator=self.operator,
+            warehouse=self.warehouse_strict_out,
+        )
+        consume_items = [{'product_id': self.product.id, 'consume_detail_ids': [11, 12], 'quantity': 50}]
+        with patch('business.services.StockFlowService') as mock_flow_cls:
+            mock_instance = mock_flow_cls.return_value
+            mock_instance.stock_out.return_value = (MagicMock(id=987), [], 2)
+
+            payload = services.create_sales_order_stock_entries_sync(
+                sales_order_id=strict_order.id,
+                warehouse_id=self.warehouse_strict_out.id,
+                items=consume_items,
+                created_by_id=self.user.id,
+            )
+
+        mock_flow_cls.assert_called_once_with(merchant=self.merchant, created_by=self.user)
+        mock_instance.stock_out.assert_called_once_with(
+            warehouse_id=self.warehouse_strict_out.id,
+            source_type=stock_models.StockChangeSourceEnum.SALES,
+            source_id=strict_order.id,
+            items=[{'product_id': self.product.id, 'consume_detail_ids': [11, 12], 'quantity': 50}],
+        )
+        self.assertEqual(payload['sales_order_id'], strict_order.id)
+        self.assertEqual(payload['stock_change_record_id'], 987)

business/tests/test_tasks.py

@@ -0,0 +1,68 @@
+from django.test import TestCase, override_settings
+from unittest.mock import patch
+
+from business import tasks
+
+
+@override_settings(
+    CELERY_TASK_ALWAYS_EAGER=True,
+    CELERY_TASK_EAGER_PROPAGATES=True,
+)
+class PurchaseOrderStockTaskTestCase(TestCase):
+    def setUp(self):
+        self.purchase_order_id = 123
+        self.warehouse_id = 456
+        self.items = [{'product_id': 1, 'quantities': ['5']}]
+
+    def test_task_delegates_to_service(self):
+        with patch('business.tasks.business_services.create_purchase_order_stock_entries_sync') as mock_sync:
+            mock_sync.return_value = {'purchase_order_id': self.purchase_order_id}
+
+            async_result = tasks.create_purchase_order_stock_entries.delay(
+                purchase_order_id=self.purchase_order_id,
+                warehouse_id=self.warehouse_id,
+                items=self.items,
+                created_by_id=999,
+            )
+            payload = async_result.get(timeout=5)
+
+        mock_sync.assert_called_once_with(
+            purchase_order_id=self.purchase_order_id,
+            warehouse_id=self.warehouse_id,
+            items=self.items,
+            created_by_id=999,
+        )
+        self.assertEqual(payload['purchase_order_id'], self.purchase_order_id)
+        self.assertIn('task_id', payload)
+
+
+@override_settings(
+    CELERY_TASK_ALWAYS_EAGER=True,
+    CELERY_TASK_EAGER_PROPAGATES=True,
+)
+class SalesOrderStockTaskTestCase(TestCase):
+    def setUp(self):
+        self.sales_order_id = 321
+        self.warehouse_id = 654
+        self.items = [{'product_id': 2, 'quantities': ['4']}]
+
+    def test_task_delegates_to_service(self):
+        with patch('business.tasks.business_services.create_sales_order_stock_entries_sync') as mock_sync:
+            mock_sync.return_value = {'sales_order_id': self.sales_order_id}
+
+            async_result = tasks.create_sales_order_stock_entries.delay(
+                sales_order_id=self.sales_order_id,
+                warehouse_id=self.warehouse_id,
+                items=self.items,
+                created_by_id=777,
+            )
+            payload = async_result.get(timeout=5)
+
+        mock_sync.assert_called_once_with(
+            sales_order_id=self.sales_order_id,
+            warehouse_id=self.warehouse_id,
+            items=self.items,
+            created_by_id=777,
+        )
+        self.assertEqual(payload['sales_order_id'], self.sales_order_id)
+        self.assertIn('task_id', payload)