Add utilities and initial test coverage

src/screens/ActivePickListScreen.tsx

@@ -31,8 +31,7 @@ import { PickItemRow } from '../components/PickItemRow';
 import { PickItem } from '../models/PickItem';
 import { Product } from '../models/Product';
 import { ProductAutocomplete } from '../components/ProductAutocomplete';
-
-const normalizeName = (name: string) => name.trim().toLowerCase();
+import { normalizeName } from '../utils/stringUtils';
 
 const ActivePickListScreen = () => {
   const { id } = useParams();

src/screens/ManageProductsScreen.tsx

@@ -24,6 +24,7 @@ import { useDatabase } from '../context/DBProvider';
 import { BarcodeScannerView } from '../components/BarcodeScannerView';
 import { ExternalProductInfo, fetchProductFromOFF } from '../modules/openFoodFacts';
 import { DEFAULT_BULK_NAME, DEFAULT_UNIT_TYPE, Product } from '../models/Product';
+import { isOnline } from '../platform/web';
 
 const ManageProductsScreen = () => {
   const db = useDatabase();
@@ -184,7 +185,7 @@ const ManageProductsScreen = () => {
 
   async function lookupBarcode(code: string) {
     if (!code) return;
-    if (typeof navigator !== 'undefined' && 'onLine' in navigator && !navigator.onLine) {
+    if (!isOnline()) {
       setLookupStatus('offline');
       setExternalProduct(null);
       return;

src/screens/__tests__/ManageProductsScreen.addAndUpdate.test.tsx

@@ -0,0 +1,151 @@
+import { MemoryRouter } from 'react-router-dom';
+import { render, screen, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import { describe, expect, it, vi, beforeEach } from 'vitest';
+import ManageProductsScreen from '../ManageProductsScreen';
+import { createMockDb } from '../../testUtils/mockDb';
+
+const mockUseProducts = vi.fn();
+const mockUseCategories = vi.fn();
+let mockDb = createMockDb();
+
+vi.mock('../../hooks/dataHooks', () => ({
+  useProducts: () => mockUseProducts(),
+  useCategories: () => mockUseCategories(),
+}));
+
+vi.mock('../../context/DBProvider', () => ({
+  useDatabase: () => mockDb,
+}));
+
+vi.mock('../../components/BarcodeScannerView', () => ({
+  BarcodeScannerView: ({ onDetected }: { onDetected?: (code: string) => void }) => (
+    <button type="button" onClick={() => onDetected?.('dup-barcode')}>
+      Mock Scan
+    </button>
+  ),
+}));
+
+const clickSaveButton = async (user: ReturnType<typeof userEvent.setup>) => {
+  const saveButton = screen
+    .getAllByRole('button')
+    .find((btn) => /save product/i.test(btn.textContent || btn.getAttribute('aria-label') || ''));
+  if (!saveButton) throw new Error('Save button not found');
+  await user.click(saveButton);
+};
+
+const selectCategory = async (user: ReturnType<typeof userEvent.setup>, name: string) => {
+  const categorySelect = screen.getByLabelText(/^category/i);
+  await user.click(categorySelect);
+  const option = await screen.findByRole('option', { name });
+  await user.click(option);
+};
+
+beforeEach(() => {
+  mockDb = createMockDb();
+  mockUseProducts.mockReturnValue([]);
+  mockUseCategories.mockReturnValue([
+    { id: 'cat-1', name: 'Snacks', created_at: 0, updated_at: 0 },
+  ]);
+});
+
+describe('ManageProductsScreen add and update flows', () => {
+  it('creates category when missing and adds product', async () => {
+    const user = userEvent.setup();
+    render(
+      <MemoryRouter>
+        <ManageProductsScreen />
+      </MemoryRouter>,
+    );
+
+    await user.type(screen.getByLabelText(/name/i), 'New Product');
+    await selectCategory(user, 'Snacks');
+    await user.type(screen.getByLabelText(/barcode/i), '111');
+    await clickSaveButton(user);
+
+    await waitFor(() => {
+      expect(mockDb.categories.items.find((c) => c.name === 'Snacks')).toBeTruthy();
+      expect(mockDb.products.items.find((p) => p.name === 'New Product')).toBeTruthy();
+    });
+  });
+
+  it('prevents duplicate barcode and shows error', async () => {
+    mockUseProducts.mockReturnValue([
+      {
+        id: 'existing',
+        name: 'Existing',
+        category: 'c1',
+        barcode: 'dup-barcode',
+        unit_type: 'unit',
+        bulk_name: 'carton',
+        archived: false,
+        created_at: 0,
+        updated_at: 0,
+      },
+    ]);
+
+    const user = userEvent.setup();
+    render(
+      <MemoryRouter>
+        <ManageProductsScreen />
+      </MemoryRouter>,
+    );
+
+    await user.type(screen.getByLabelText(/name/i), 'Another');
+    await selectCategory(user, 'Snacks');
+    await user.click(screen.getByText(/scan barcode/i));
+    await user.click(screen.getByText(/mock scan/i));
+    await waitFor(() => expect(screen.queryByRole('dialog')).not.toBeInTheDocument());
+    await clickSaveButton(user);
+
+    await waitFor(() => {
+      expect(screen.getByTestId('barcode-error')).toBeInTheDocument();
+      expect(mockDb.products.items.find((p) => p.name === 'Another')).toBeUndefined();
+    });
+  });
+
+  it('auto-adds new product to eligible pick lists', async () => {
+    const timestamp = Date.now();
+    mockDb = createMockDb({
+      pickLists: [
+        {
+          id: 'list-1',
+          area_id: 'a',
+          created_at: timestamp,
+          completed_at: undefined,
+          notes: 'List One',
+          categories: ['Fresh'],
+          auto_add_new_products: true,
+        },
+        {
+          id: 'list-2',
+          area_id: 'b',
+          created_at: timestamp,
+          completed_at: undefined,
+          notes: 'List Two',
+          categories: ['different'],
+          auto_add_new_products: true,
+        },
+      ],
+      categories: [{ id: 'fresh-id', name: 'Fresh', created_at: timestamp, updated_at: timestamp }],
+    });
+    mockUseProducts.mockReturnValue([]);
+    mockUseCategories.mockReturnValue([{ id: 'fresh-id', name: 'Fresh', created_at: timestamp, updated_at: timestamp }]);
+
+    const user = userEvent.setup();
+    render(
+      <MemoryRouter>
+        <ManageProductsScreen />
+      </MemoryRouter>,
+    );
+
+    await user.type(screen.getByLabelText(/name/i), 'Lettuce');
+    await selectCategory(user, 'Fresh');
+    await clickSaveButton(user);
+
+    await waitFor(() => {
+      expect(mockDb.pickItems.items.some((item) => item.pick_list_id === 'list-1')).toBe(true);
+      expect(mockDb.pickItems.items.some((item) => item.pick_list_id === 'list-2')).toBe(false);
+    });
+  });
+});