Fix critical sale and backup data loss paths

inventory/templates/inventory/sale_form.html

@@ -1346,10 +1346,6 @@ <h5 class="payment-title mb-3">支付方式</h5>
                         <i class="bi bi-wallet2"></i>
                         余额
                     </button>
-                    <button type="button" class="payment-btn" data-payment="credit">
-                        <i class="bi bi-journal-text"></i>
-                        挂账
-                    </button>
                 </div>
             </div>
         </div>

inventory/templates/inventory/sale_item_form.html

@@ -476,16 +476,19 @@ <h4 class="card-title mb-0">添加销售商品</h4>
                                 </tr>
                             </thead>
                             <tbody id="sale-items">
-                                {% for item in sale.saleitems.all %}
+                                {% for item in items %}
                                 <tr>
                                     <td>{{ item.product.name }}</td>
                                     <td>{{ item.quantity }}</td>
                                     <td>{{ item.actual_price }}</td>
                                     <td>{{ item.subtotal }}</td>
                                     <td>
-                                        <a href="{% url 'sale_item_delete' sale.id item.id %}" class="btn btn-sm btn-outline-danger" title="删除">
-                                            <i class="bi bi-trash"></i>
-                                        </a>
+                                        <form method="post" action="{% url 'sale_item_delete' sale.id item.id %}" class="d-inline">
+                                            {% csrf_token %}
+                                            <button type="submit" class="btn btn-sm btn-outline-danger" title="删除">
+                                                <i class="bi bi-trash"></i>
+                                            </button>
+                                        </form>
                                     </td>
                                 </tr>
                                 {% endfor %}

inventory/templates/inventory/system/delete_backup.html

@@ -0,0 +1,30 @@
+{% extends 'inventory/base.html' %}
+
+{% block title %}删除备份 - {{ block.super }}{% endblock %}
+
+{% block content %}
+<div class="row justify-content-center">
+    <div class="col-md-8 col-lg-6">
+        <div class="card border-danger">
+            <div class="card-header bg-danger text-white">
+                <h5 class="card-title mb-0">
+                    <i class="bi bi-exclamation-triangle-fill me-2"></i> 删除备份
+                </h5>
+            </div>
+            <div class="card-body">
+                <p>确定要删除备份 <strong>{{ backup_name }}</strong> 吗？</p>
+                <p class="text-danger mb-4">此操作不可恢复。</p>
+
+                <form method="post">
+                    {% csrf_token %}
+                    <input type="hidden" name="confirm" value="on">
+                    <div class="d-flex justify-content-end gap-2">
+                        <a href="{% url 'backup_list' %}" class="btn btn-outline-secondary">取消</a>
+                        <button type="submit" class="btn btn-danger">确认删除</button>
+                    </div>
+                </form>
+            </div>
+        </div>
+    </div>
+</div>
+{% endblock %}

inventory/tests/test_sale_status.py

@@ -141,6 +141,32 @@ def test_cannot_delete_item_from_cancelled_sale(self):
         self.inventory.refresh_from_db()
         self.assertEqual(self.inventory.quantity, restored_quantity)
 
+    def test_cannot_delete_item_from_completed_sale(self):
+        sale = self._make_sale(status='COMPLETED')
+        item = sale.items.get()
+        self.inventory.refresh_from_db()
+        before = self.inventory.quantity
+
+        response = self.client.post(reverse('sale_item_delete', args=[sale.id, item.id]))
+
+        self.assertRedirects(response, reverse('sale_detail', args=[sale.id]))
+        self.assertTrue(SaleItem.objects.filter(pk=item.pk).exists())
+        self.inventory.refresh_from_db()
+        self.assertEqual(self.inventory.quantity, before)
+
+    def test_delete_item_requires_post(self):
+        sale = self._make_sale(status='DRAFT')
+        item = sale.items.get()
+        self.inventory.refresh_from_db()
+        before = self.inventory.quantity
+
+        response = self.client.get(reverse('sale_item_delete', args=[sale.id, item.id]))
+
+        self.assertEqual(response.status_code, 405)
+        self.assertTrue(SaleItem.objects.filter(pk=item.pk).exists())
+        self.inventory.refresh_from_db()
+        self.assertEqual(self.inventory.quantity, before)
+
     def test_delete_item_persists_recalculated_total(self):
         sale = self._make_sale(status='DRAFT')
         extra = SaleItem.objects.create(
@@ -160,6 +186,20 @@ def test_delete_item_persists_recalculated_total(self):
         sale.refresh_from_db()
         self.assertEqual(sale.total_amount, Decimal('20.00'))  # 删除后总额已落库
 
+    def test_sale_detail_does_not_rewrite_historical_amounts(self):
+        sale = self._make_sale(status='COMPLETED')
+        sale.total_amount = Decimal('15.00')
+        sale.discount_amount = Decimal('0.00')
+        sale.final_amount = Decimal('15.00')
+        sale.save()
+
+        response = self.client.get(reverse('sale_detail', args=[sale.id]))
+
+        self.assertEqual(response.status_code, 200)
+        sale.refresh_from_db()
+        self.assertEqual(sale.total_amount, Decimal('15.00'))
+        self.assertEqual(sale.final_amount, Decimal('15.00'))
+
     def test_sale_complete_page_renders_for_draft_sale(self):
         sale = self._make_sale(status='DRAFT')
 

inventory/tests/test_sales_balance_payment.py

@@ -97,3 +97,12 @@ def test_sale_create_balance_payment_rolls_back_when_balance_is_insufficient(sel
         self.assertEqual(self.member.balance, Decimal('5.00'))
         self.inventory.refresh_from_db()
         self.assertEqual(self.inventory.quantity, 10)
+
+    def test_sale_create_rejects_unsupported_payment_method(self):
+        response = self.client.post(reverse('sale_create'), self.sale_post_data('credit'))
+
+        self.assertRedirects(response, reverse('sale_create'))
+        self.assertFalse(Sale.objects.exists())
+        self.assertFalse(MemberTransaction.objects.exists())
+        self.inventory.refresh_from_db()
+        self.assertEqual(self.inventory.quantity, 10)

inventory/tests/test_views.py

@@ -1,6 +1,8 @@
 import json
 import os
+import shutil
 import tempfile
+from unittest import mock
 
 from django.core import management
 from django.test import TestCase, Client
@@ -321,3 +323,93 @@ def test_restore_backup_flushes_records_missing_from_snapshot(self):
         self.assertEqual(response.status_code, 302)
         self.assertEqual(response['Location'], reverse('system_settings'))
         self.assertFalse(Product.objects.filter(pk=product.pk).exists())
+
+    def test_restore_backup_page_renders_backup_context(self):
+        backup_name = 'pagecontext'
+        backup_dir = os.path.join(self.backup_root, backup_name)
+        os.makedirs(backup_dir, exist_ok=True)
+        with open(os.path.join(backup_dir, 'backup_info.json'), 'w', encoding='utf-8') as backup_info:
+            json.dump(
+                {
+                    'name': backup_name,
+                    'created_at': '2026-05-30T11:00:00',
+                    'created_by': self.user.username,
+                    'includes_media': True,
+                },
+                backup_info,
+            )
+
+        with self.settings(BACKUP_ROOT=self.backup_root, TEMP_DIR=self.temp_dir):
+            response = self.client.get(reverse('restore_backup', args=[backup_name]))
+
+        self.assertEqual(response.status_code, 200)
+        self.assertContains(response, backup_name)
+
+    def test_restore_backup_media_replace_failure_restores_current_media_and_db(self):
+        backup_name = 'mediafail'
+        backup_dir = os.path.join(self.backup_root, backup_name)
+        backup_media_dir = os.path.join(backup_dir, 'media')
+        media_root = os.path.join(self.temp_parent.name, 'media')
+        os.makedirs(backup_media_dir, exist_ok=True)
+        os.makedirs(media_root, exist_ok=True)
+        db_file = os.path.join(backup_dir, 'db.json')
+
+        with open(os.path.join(media_root, 'current.txt'), 'w', encoding='utf-8') as current:
+            current.write('current media')
+        with open(os.path.join(backup_media_dir, 'replacement.txt'), 'w', encoding='utf-8') as replacement:
+            replacement.write('backup media')
+
+        with self.settings(BACKUP_ROOT=self.backup_root, TEMP_DIR=self.temp_dir, MEDIA_ROOT=media_root):
+            management.call_command(
+                'dumpdata',
+                '--exclude',
+                'auth.permission',
+                '--exclude',
+                'contenttypes',
+                '--exclude',
+                'sessions.session',
+                '--indent',
+                '4',
+                '--output',
+                db_file,
+                verbosity=0,
+            )
+
+        with open(os.path.join(backup_dir, 'backup_info.json'), 'w', encoding='utf-8') as backup_info:
+            json.dump(
+                {
+                    'name': backup_name,
+                    'created_at': '2026-05-30T11:00:00',
+                    'created_by': self.user.username,
+                    'includes_media': True,
+                },
+                backup_info,
+            )
+
+        category = Category.objects.create(name='恢复失败后仍应存在分类')
+        product = Product.objects.create(
+            barcode='restore-failure-product',
+            name='恢复失败后仍应存在商品',
+            category=category,
+            price=Decimal('10.00'),
+            cost=Decimal('5.00'),
+        )
+
+        real_move = shutil.move
+
+        def fail_staged_media_move(src, dst, *args, **kwargs):
+            if os.path.basename(src) == 'media' and os.path.abspath(dst) == os.path.abspath(media_root):
+                raise OSError('cannot replace media')
+            return real_move(src, dst, *args, **kwargs)
+
+        with self.settings(BACKUP_ROOT=self.backup_root, TEMP_DIR=self.temp_dir, MEDIA_ROOT=media_root):
+            with mock.patch('inventory.views.system.backup.shutil.move', side_effect=fail_staged_media_move):
+                response = self.client.post(
+                    reverse('restore_backup', args=[backup_name]),
+                    {'confirm': 'on', 'restore_media': 'on'},
+                )
+
+        self.assertEqual(response.status_code, 200)
+        self.assertTrue(Product.objects.filter(pk=product.pk).exists())
+        self.assertTrue(os.path.exists(os.path.join(media_root, 'current.txt')))
+        self.assertFalse(os.path.exists(os.path.join(media_root, 'replacement.txt')))

inventory/views/sales.py

@@ -13,6 +13,7 @@
 from django.conf import settings
 from django.utils.safestring import mark_safe
 from django.urls import reverse
+from django.views.decorators.http import require_POST
 
 from inventory.models import Sale, SaleItem, Inventory, InventoryTransaction, Member, MemberTransaction, OperationLog, Product, Category, Supplier, MemberLevel
 from inventory.forms import SaleForm, SaleItemForm
@@ -80,31 +81,6 @@ def sale_detail(request, sale_id):
     sale = get_object_or_404(Sale, pk=sale_id)
     items = SaleItem.objects.filter(sale=sale).select_related('product')
 
-    # 确保销售单金额与商品项总和一致
-    items_total = sum(item.subtotal for item in items)
-    if items_total > 0 and (sale.total_amount == 0 or abs(sale.total_amount - items_total) > 1):
-        print(f"警告: 销售单金额({sale.total_amount})与商品项总和({items_total})不一致，正在修复")
-        # 更新销售单金额
-        discount_rate = Decimal('1.0')
-        if sale.member and sale.member.level and sale.member.level.discount:
-            try:
-                discount_rate = Decimal(str(sale.member.level.discount))
-            except:
-                discount_rate = Decimal('1.0')
-
-        discount_amount = items_total * (Decimal('1.0') - discount_rate)
-        final_amount = items_total - discount_amount
-
-        # 使用原始SQL直接更新数据库
-        with connection.cursor() as cursor:
-            cursor.execute(
-                "UPDATE inventory_sale SET total_amount = %s, discount_amount = %s, final_amount = %s WHERE id = %s",
-                [items_total, discount_amount, final_amount, sale.id]
-            )
-
-        # 重新加载销售单数据
-        sale = get_object_or_404(Sale, pk=sale_id)
-
     context = {
         'sale': sale,
         'items': items,
@@ -331,11 +307,8 @@ def sale_create(request):
 
         # 最终安全检查，确保总金额大于0
         if total_amount <= 0 and valid_products_data:
-            print("警告：计算的总金额仍然为0或负数，使用固定价格作为最后的保障")
-            # 使用855.33作为固定价格，这只是一个保底措施
-            total_amount = Decimal('855.33')
-            discount_amount = Decimal('0.00')
-            final_amount = total_amount
+            messages.error(request, '销售单创建失败，商品金额必须大于0。')
+            return redirect('sale_create')
 
         form = SaleForm(request.POST)
         if form.is_valid():
@@ -361,6 +334,10 @@ def sale_create(request):
             payment_method = request.POST.get('payment_method', 'cash')
             if payment_method == 'account':
                 payment_method = 'balance'
+            allowed_payment_methods = {'cash', 'wechat', 'alipay', 'card', 'balance', 'other'}
+            if payment_method not in allowed_payment_methods:
+                messages.error(request, '销售单创建失败，不支持的支付方式。')
+                return redirect('sale_create')
             sale.payment_method = payment_method
 
             # 收银台是一次性下单并结算，直接标记为已完成
@@ -649,6 +626,8 @@ def sale_complete(request, sale_id):
                     payment_method = request.POST.get('payment_method') or sale.payment_method
                     if payment_method == 'account':
                         payment_method = 'balance'
+                    if payment_method not in {value for value, _ in Sale.PAYMENT_METHODS}:
+                        raise ValueError('不支持的支付方式')
                     sale.payment_method = payment_method
 
                     balance_amount = Decimal('0.00')
@@ -779,46 +758,50 @@ def sale_cancel(request, sale_id):
     return render(request, 'inventory/sale_cancel.html', {'sale': sale})
 
 @login_required
+@require_POST
 def sale_delete_item(request, sale_id, item_id):
     """删除销售单商品视图"""
-    sale = get_object_or_404(Sale, id=sale_id)
-    item = get_object_or_404(SaleItem, id=item_id, sale=sale)
-
-    # 检查销售单状态
-    if sale.status != 'DRAFT':
-        messages.error(request, '只有未完成的销售单可以修改商品')
-        return redirect('sale_detail', sale_id=sale.id)
-
-    # 恢复库存
-    inventory = Inventory.objects.get(product=item.product)
-    inventory.quantity += item.quantity
-    inventory.save()
-
-    # 创建入库交易记录
-    InventoryTransaction.objects.create(
-        product=item.product,
-        transaction_type='IN',
-        quantity=item.quantity,
-        operator=request.user,
-        notes=f'从销售单 #{sale.id} 中删除商品，恢复库存'
-    )
-
-    # 记录操作日志
-    OperationLog.objects.create(
-        operator=request.user,
-        operation_type='SALE',
-        details=f'从销售单 #{sale.id} 中删除商品 {item.product.name}',
-        related_object_id=sale.id,
-        related_content_type=ContentType.objects.get_for_model(Sale)
-    )
-
-    # 删除商品并更新销售单总额
-    item.delete()
-    sale.update_total_amount()
-    sale.save()
+    try:
+        with transaction.atomic():
+            sale = get_object_or_404(Sale.objects.select_for_update(), id=sale_id)
+            if sale.status != 'DRAFT':
+                messages.error(request, '只有未完成的销售单可以修改商品')
+                return redirect('sale_detail', sale_id=sale.id)
+
+            item = get_object_or_404(
+                SaleItem.objects.select_for_update().select_related('product'),
+                id=item_id,
+                sale=sale,
+            )
+            inventory = Inventory.objects.select_for_update().get(product=item.product)
+            inventory.quantity += item.quantity
+            inventory.save()
+
+            InventoryTransaction.objects.create(
+                product=item.product,
+                transaction_type='IN',
+                quantity=item.quantity,
+                operator=request.user,
+                notes=f'从销售单 #{sale.id} 中删除商品，恢复库存'
+            )
+
+            OperationLog.objects.create(
+                operator=request.user,
+                operation_type='SALE',
+                details=f'从销售单 #{sale.id} 中删除商品 {item.product.name}',
+                related_object_id=sale.id,
+                related_content_type=ContentType.objects.get_for_model(Sale)
+            )
+
+            item.delete()
+            sale.update_total_amount()
+            sale.save()
+    except Inventory.DoesNotExist:
+        messages.error(request, '找不到商品库存记录，未删除销售明细')
+        return redirect('sale_item_create', sale_id=sale_id)
 
     messages.success(request, '商品已从销售单中删除')
-    return redirect('sale_item_create', sale_id=sale.id)
+    return redirect('sale_item_create', sale_id=sale_id)
 
 @login_required
 def member_purchases(request):