CW-STORY-04.2: search and view products

IProductService/ProductService return display-ready DTOs (BrandName/
ConceptName resolved via join) rather than raw Product entities.
ProductController routes match AGENTS.md §11; price/insight fields
deferred until CW-EPIC-05 exists.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docs/scrum-backlog.md

@@ -454,13 +454,15 @@ Two more real bugs found by tests (bringing the running total for `CW-EPIC-03` t
 - Household price insights can be shown later on the details page
 
 **Tasks**
-- [ ] Create `IProductService`
-- [ ] Implement local catalog search
-- [ ] Create `ProductController`
-- [ ] Build `Views/Product/Search.cshtml`
-- [ ] Build `Views/Product/Details.cshtml`
-- [ ] Add product view models
-- [ ] Add tests
+- [x] Create `IProductService`
+- [x] Implement local catalog search
+- [x] Create `ProductController`
+- [x] Build `Views/Product/Search.cshtml`
+- [x] Build `Views/Product/Details.cshtml`
+- [x] Add product view models
+- [x] Add tests
+
+**Status:** Done — `IProductService`/`ProductService` return `ProductSummaryDto`/`ProductDetailsDto` (new `CartWise.Application.DTOs`) rather than raw `Product` entities, since search/details need `BrandName`/`ConceptName` resolved via joins that don't belong on the Domain entity itself. Search is a simple `NormalizedName.Contains(...)` match, capped at 25 results. `ProductController` routes (`/products/search`, `/products/{id:guid}`) match AGENTS.md §11 exactly; `Details` 404s for an unknown id. Price/household-insight fields from AGENTS.md §12's `ProductDetailsViewModel` were intentionally omitted — the acceptance criteria itself says "can be shown *later*," and `CW-EPIC-05` (price intelligence) doesn't exist yet; the details page has a placeholder note instead of empty stub fields. 5 application tests + 3 Web tests added.
 
 ### `CW-STORY-04.3` Implement barcode lookup flow
 **Release:** Deferred  

src/CartWise.Application/ApplicationServiceCollectionExtensions.cs

@@ -11,6 +11,7 @@ public static class ApplicationServiceCollectionExtensions
         services.AddSingleton(TimeProvider.System);
         services.AddScoped<IHouseholdService, HouseholdService>();
         services.AddScoped<IShoppingListService, ShoppingListService>();
+        services.AddScoped<IProductService, ProductService>();
 
         return services;
     }

src/CartWise.Application/DTOs/ProductDetailsDto.cs

@@ -0,0 +1,18 @@
+namespace CartWise.Application.DTOs;
+
+public class ProductDetailsDto
+{
+    public Guid ProductId { get; init; }
+
+    public string Name { get; init; } = string.Empty;
+
+    public string? BrandName { get; init; }
+
+    public string? ConceptName { get; init; }
+
+    public string? PackageDisplay { get; init; }
+
+    public string? ImageUrl { get; init; }
+
+    public IReadOnlyList<string> BarcodeIdentifiers { get; init; } = [];
+}

src/CartWise.Application/DTOs/ProductSummaryDto.cs

@@ -0,0 +1,14 @@
+namespace CartWise.Application.DTOs;
+
+public class ProductSummaryDto
+{
+    public Guid ProductId { get; init; }
+
+    public string Name { get; init; } = string.Empty;
+
+    public string? BrandName { get; init; }
+
+    public string? PackageDisplay { get; init; }
+
+    public string? ImageUrl { get; init; }
+}

src/CartWise.Application/Interfaces/IApplicationDbContext.cs

@@ -14,6 +14,14 @@ public interface IApplicationDbContext
 
     DbSet<ShoppingListItem> ShoppingListItems { get; }
 
+    DbSet<GroceryConcept> GroceryConcepts { get; }
+
+    DbSet<Brand> Brands { get; }
+
+    DbSet<Product> Products { get; }
+
+    DbSet<ProductIdentifier> ProductIdentifiers { get; }
+
     EntityEntry<TEntity> Entry<TEntity>(TEntity entity) where TEntity : class;
 
     Task<int> SaveChangesAsync(CancellationToken cancellationToken = default);

src/CartWise.Application/Interfaces/IProductService.cs

@@ -0,0 +1,10 @@
+using CartWise.Application.DTOs;
+
+namespace CartWise.Application.Interfaces;
+
+public interface IProductService
+{
+    Task<IReadOnlyList<ProductSummaryDto>> SearchAsync(string query, CancellationToken cancellationToken = default);
+
+    Task<ProductDetailsDto?> GetDetailsAsync(Guid productId, CancellationToken cancellationToken = default);
+}

src/CartWise.Application/Services/ProductService.cs

@@ -0,0 +1,90 @@
+using System.Globalization;
+using CartWise.Application.DTOs;
+using CartWise.Application.Interfaces;
+using Microsoft.EntityFrameworkCore;
+
+namespace CartWise.Application.Services;
+
+public class ProductService : IProductService
+{
+    private readonly IApplicationDbContext _db;
+
+    public ProductService(IApplicationDbContext db)
+    {
+        _db = db;
+    }
+
+    public async Task<IReadOnlyList<ProductSummaryDto>> SearchAsync(string query, CancellationToken cancellationToken = default)
+    {
+        if (string.IsNullOrWhiteSpace(query))
+        {
+            return [];
+        }
+
+        var normalizedQuery = query.Trim().ToUpperInvariant();
+
+        var rows = await (
+            from product in _db.Products
+            join brand in _db.Brands on product.BrandId equals brand.BrandId into brandJoin
+            from brand in brandJoin.DefaultIfEmpty()
+            where product.NormalizedName.Contains(normalizedQuery)
+            orderby product.Name
+            select new { product, BrandName = brand != null ? brand.Name : null }
+        )
+        .AsNoTracking()
+        .Take(25)
+        .ToListAsync(cancellationToken);
+
+        return rows.Select(row => new ProductSummaryDto
+        {
+            ProductId = row.product.ProductId,
+            Name = row.product.Name,
+            BrandName = row.BrandName,
+            PackageDisplay = FormatPackage(row.product.SizeValue, row.product.SizeUnit),
+            ImageUrl = row.product.ImageUrl
+        }).ToList();
+    }
+
+    public async Task<ProductDetailsDto?> GetDetailsAsync(Guid productId, CancellationToken cancellationToken = default)
+    {
+        var product = await _db.Products
+            .Include(p => p.Identifiers)
+            .AsNoTracking()
+            .FirstOrDefaultAsync(p => p.ProductId == productId, cancellationToken);
+
+        if (product is null)
+        {
+            return null;
+        }
+
+        var brandName = product.BrandId is null
+            ? null
+            : await _db.Brands.AsNoTracking().Where(b => b.BrandId == product.BrandId).Select(b => b.Name).FirstOrDefaultAsync(cancellationToken);
+
+        var conceptName = product.GroceryConceptId is null
+            ? null
+            : await _db.GroceryConcepts.AsNoTracking().Where(c => c.GroceryConceptId == product.GroceryConceptId).Select(c => c.Name).FirstOrDefaultAsync(cancellationToken);
+
+        return new ProductDetailsDto
+        {
+            ProductId = product.ProductId,
+            Name = product.Name,
+            BrandName = brandName,
+            ConceptName = conceptName,
+            PackageDisplay = FormatPackage(product.SizeValue, product.SizeUnit),
+            ImageUrl = product.ImageUrl,
+            BarcodeIdentifiers = product.Identifiers.Select(i => i.Value).ToList()
+        };
+    }
+
+    private static string? FormatPackage(decimal? sizeValue, string? sizeUnit)
+    {
+        if (sizeValue is null)
+        {
+            return sizeUnit;
+        }
+
+        var text = sizeValue.Value.ToString("0.###", CultureInfo.InvariantCulture);
+        return sizeUnit is null ? text : $"{text} {sizeUnit}";
+    }
+}

src/CartWise.Web/Controllers/ProductController.cs

@@ -0,0 +1,63 @@
+using CartWise.Application.Interfaces;
+using CartWise.Web.ViewModels.Product;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+namespace CartWise.Web.Controllers;
+
+[Authorize]
+public class ProductController : Controller
+{
+    private readonly IProductService _productService;
+
+    public ProductController(IProductService productService)
+    {
+        _productService = productService;
+    }
+
+    [HttpGet("products/search")]
+    public async Task<IActionResult> Search(string? q)
+    {
+        var results = string.IsNullOrWhiteSpace(q)
+            ? []
+            : await _productService.SearchAsync(q);
+
+        var viewModel = new ProductSearchViewModel
+        {
+            Query = q,
+            Results = results.Select(r => new ProductSearchResultViewModel
+            {
+                ProductId = r.ProductId,
+                Name = r.Name,
+                BrandName = r.BrandName,
+                PackageDisplay = r.PackageDisplay,
+                ImageUrl = r.ImageUrl
+            }).ToList()
+        };
+
+        return View(viewModel);
+    }
+
+    [HttpGet("products/{id:guid}")]
+    public async Task<IActionResult> Details(Guid id)
+    {
+        var details = await _productService.GetDetailsAsync(id);
+        if (details is null)
+        {
+            return NotFound();
+        }
+
+        var viewModel = new ProductDetailsViewModel
+        {
+            ProductId = details.ProductId,
+            Name = details.Name,
+            BrandName = details.BrandName,
+            ConceptName = details.ConceptName,
+            PackageDisplay = details.PackageDisplay,
+            ImageUrl = details.ImageUrl,
+            BarcodeIdentifiers = details.BarcodeIdentifiers.ToList()
+        };
+
+        return View(viewModel);
+    }
+}

src/CartWise.Web/ViewModels/Product/ProductDetailsViewModel.cs

@@ -0,0 +1,18 @@
+namespace CartWise.Web.ViewModels.Product;
+
+public class ProductDetailsViewModel
+{
+    public Guid ProductId { get; set; }
+
+    public string Name { get; set; } = string.Empty;
+
+    public string? BrandName { get; set; }
+
+    public string? ConceptName { get; set; }
+
+    public string? PackageDisplay { get; set; }
+
+    public string? ImageUrl { get; set; }
+
+    public List<string> BarcodeIdentifiers { get; set; } = [];
+}

src/CartWise.Web/ViewModels/Product/ProductSearchViewModel.cs

@@ -0,0 +1,21 @@
+namespace CartWise.Web.ViewModels.Product;
+
+public class ProductSearchViewModel
+{
+    public string? Query { get; set; }
+
+    public List<ProductSearchResultViewModel> Results { get; set; } = [];
+}
+
+public class ProductSearchResultViewModel
+{
+    public Guid ProductId { get; set; }
+
+    public string Name { get; set; } = string.Empty;
+
+    public string? BrandName { get; set; }
+
+    public string? PackageDisplay { get; set; }
+
+    public string? ImageUrl { get; set; }
+}

src/CartWise.Web/Views/Product/Details.cshtml

@@ -0,0 +1,32 @@
+@model CartWise.Web.ViewModels.Product.ProductDetailsViewModel
+@{
+    ViewData["Title"] = Model.Name;
+}
+
+<h1>@Model.Name</h1>
+
+@if (!string.IsNullOrEmpty(Model.BrandName))
+{
+    <p class="text-muted mb-1">@Model.BrandName</p>
+}
+@if (!string.IsNullOrEmpty(Model.ConceptName))
+{
+    <p class="text-muted mb-1">Concept: @Model.ConceptName</p>
+}
+@if (!string.IsNullOrEmpty(Model.PackageDisplay))
+{
+    <p class="text-muted mb-1">Size: @Model.PackageDisplay</p>
+}
+
+@if (Model.BarcodeIdentifiers.Count > 0)
+{
+    <h2 class="h5 mt-4">Identifiers</h2>
+    <ul>
+        @foreach (var identifier in Model.BarcodeIdentifiers)
+        {
+            <li>@identifier</li>
+        }
+    </ul>
+}
+
+<p class="text-muted mt-4"><em>Price history and household insights will appear here once purchase tracking is available.</em></p>

src/CartWise.Web/Views/Product/Search.cshtml

@@ -0,0 +1,40 @@
+@model CartWise.Web.ViewModels.Product.ProductSearchViewModel
+@{
+    ViewData["Title"] = "Search products";
+}
+
+<h1>Search products</h1>
+
+<form asp-controller="Product" asp-action="Search" method="get" class="row g-2 mb-4">
+    <div class="col-9 col-sm-8">
+        <label for="q" class="visually-hidden">Search</label>
+        <input type="text" id="q" name="q" class="form-control" placeholder="Search products" value="@Model.Query" />
+    </div>
+    <div class="col-3 col-sm-2">
+        <button type="submit" class="btn btn-primary w-100">Search</button>
+    </div>
+</form>
+
+@if (!string.IsNullOrWhiteSpace(Model.Query) && Model.Results.Count == 0)
+{
+    <p class="text-muted">No products matched "@Model.Query".</p>
+}
+else if (Model.Results.Count > 0)
+{
+    <ul class="list-group">
+        @foreach (var result in Model.Results)
+        {
+            <li class="list-group-item">
+                <a asp-controller="Product" asp-action="Details" asp-route-id="@result.ProductId">@result.Name</a>
+                @if (!string.IsNullOrEmpty(result.BrandName))
+                {
+                    <span class="text-muted"> — @result.BrandName</span>
+                }
+                @if (!string.IsNullOrEmpty(result.PackageDisplay))
+                {
+                    <span class="text-muted"> (@result.PackageDisplay)</span>
+                }
+            </li>
+        }
+    </ul>
+}

tests/CartWise.Application.Tests/ProductServiceTests.cs

@@ -0,0 +1,96 @@
+using CartWise.Application.Services;
+using CartWise.Domain.Entities;
+using CartWise.Domain.Enums;
+using CartWise.Infrastructure.Data;
+using Microsoft.EntityFrameworkCore;
+
+namespace CartWise.Application.Tests;
+
+public class ProductServiceTests : IDisposable
+{
+    private static readonly DateTime Now = new(2026, 8, 10, 12, 0, 0, DateTimeKind.Utc);
+
+    private readonly CartWiseDbContext _db;
+    private readonly ProductService _sut;
+
+    public ProductServiceTests()
+    {
+        var options = new DbContextOptionsBuilder<CartWiseDbContext>()
+            .UseInMemoryDatabase(Guid.NewGuid().ToString())
+            .Options;
+
+        _db = new CartWiseDbContext(options);
+        _sut = new ProductService(_db);
+    }
+
+    public void Dispose()
+    {
+        _db.Dispose();
+        GC.SuppressFinalize(this);
+    }
+
+    [Fact]
+    public async Task SearchAsync_ReturnsMatchingProductsWithBrandName()
+    {
+        var brand = new Brand("Jif");
+        var product = new Product("Jif Creamy Peanut Butter", ProductSourceType.Manual, Now, brandId: brand.BrandId, sizeValue: 16m, sizeUnit: "oz");
+        _db.Brands.Add(brand);
+        _db.Products.Add(product);
+        await _db.SaveChangesAsync();
+
+        var results = await _sut.SearchAsync("peanut");
+
+        var result = Assert.Single(results);
+        Assert.Equal("Jif Creamy Peanut Butter", result.Name);
+        Assert.Equal("Jif", result.BrandName);
+        Assert.Equal("16 oz", result.PackageDisplay);
+    }
+
+    [Fact]
+    public async Task SearchAsync_ReturnsEmptyForBlankQuery()
+    {
+        var results = await _sut.SearchAsync("   ");
+
+        Assert.Empty(results);
+    }
+
+    [Fact]
+    public async Task SearchAsync_ReturnsEmptyWhenNothingMatches()
+    {
+        _db.Products.Add(new Product("Whole Milk", ProductSourceType.Manual, Now));
+        await _db.SaveChangesAsync();
+
+        var results = await _sut.SearchAsync("cereal");
+
+        Assert.Empty(results);
+    }
+
+    [Fact]
+    public async Task GetDetailsAsync_ReturnsNullWhenProductDoesNotExist()
+    {
+        var details = await _sut.GetDetailsAsync(Guid.NewGuid());
+
+        Assert.Null(details);
+    }
+
+    [Fact]
+    public async Task GetDetailsAsync_ReturnsBrandConceptAndIdentifiers()
+    {
+        var brand = new Brand("Jif");
+        var concept = new GroceryConcept("Peanut Butter", Now);
+        var product = new Product("Jif Creamy 16 oz", ProductSourceType.Manual, Now, groceryConceptId: concept.GroceryConceptId, brandId: brand.BrandId);
+        product.AddIdentifier(ProductIdentifierType.UpcA, "051500255516");
+
+        _db.Brands.Add(brand);
+        _db.GroceryConcepts.Add(concept);
+        _db.Products.Add(product);
+        await _db.SaveChangesAsync();
+
+        var details = await _sut.GetDetailsAsync(product.ProductId);
+
+        Assert.NotNull(details);
+        Assert.Equal("Jif", details!.BrandName);
+        Assert.Equal("Peanut Butter", details.ConceptName);
+        Assert.Equal("051500255516", Assert.Single(details.BarcodeIdentifiers));
+    }
+}

tests/CartWise.Web.Tests/ProductAccessControlTests.cs

@@ -0,0 +1,49 @@
+using System.Net;
+using Microsoft.AspNetCore.Mvc.Testing;
+
+namespace CartWise.Web.Tests;
+
+public class ProductAccessControlTests : IClassFixture<CartWiseWebApplicationFactory>
+{
+    private readonly CartWiseWebApplicationFactory _factory;
+
+    public ProductAccessControlTests(CartWiseWebApplicationFactory factory)
+    {
+        _factory = factory;
+    }
+
+    [Fact]
+    public async Task AnonymousUser_IsRedirectedToLoginWhenSearchingProducts()
+    {
+        var client = _factory.CreateClient(new WebApplicationFactoryClientOptions { AllowAutoRedirect = false });
+
+        var response = await client.GetAsync("/products/search?q=milk");
+
+        Assert.Equal(HttpStatusCode.Redirect, response.StatusCode);
+        Assert.Contains("/Account/Login", response.Headers.Location?.ToString());
+    }
+
+    [Fact]
+    public async Task AuthenticatedUser_CanSearchWithNoResults()
+    {
+        var client = _factory.CreateClient();
+        await WebTestHelpers.RegisterAsync(client, "productsearch1@example.com", "Product Searcher");
+
+        var response = await client.GetAsync("/products/search?q=nonexistentitem");
+
+        response.EnsureSuccessStatusCode();
+        var body = await response.Content.ReadAsStringAsync();
+        HtmlAssert.Contains("No products matched", body);
+    }
+
+    [Fact]
+    public async Task Details_ReturnsNotFoundForUnknownProduct()
+    {
+        var client = _factory.CreateClient();
+        await WebTestHelpers.RegisterAsync(client, "productdetails1@example.com", "Product Detailer");
+
+        var response = await client.GetAsync($"/products/{Guid.NewGuid()}");
+
+        Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
+    }
+}