[Refactor] Blazor Blueprint app shell and Blazor Web App hosting

CLAUDE.md

@@ -67,8 +67,12 @@ URLs follow `/reqif/{header-identifier}/<entity>/<entity-identifier>`. The `Spec
 
 ### Layout / UI stack
 
-- `App.razor` → `Shared/MainLayout.razor` (Radzen layout + a `BSOffCanvas` from BlazorStrap V5 for the `SideMenu`).
-- UI libraries: **Radzen.Blazor**, **BlazorStrap.V5**, plus **Blazor-Analytics** (Google Analytics ID hard-coded in `Program.cs`).
+- Hosting is the Blazor Web App model: `App.razor` is the host page, `Routes.razor` the router, and the whole app runs with the `InteractiveServer` render mode (`MapRazorComponents<App>().AddInteractiveServerRenderMode()` in `Program.cs`).
+- The UI is moving from **Radzen.Blazor** to **[Blazor Blueprint](https://blazorblueprintui.com)** (`BlazorBlueprint.Components`, Lucide icons). The shell is already Blueprint: `Shared/MainLayout.razor` (`BbSidebarProvider`, header with `BbDarkModeToggle`) and `Shared/SideMenu.razor` (`BbSidebar`). The pages still use Radzen components and the Bootstrap grid.
+- Both libraries define types with the same names (`DialogService`, `ButtonSize`, ...), so Blueprint is imported per folder: `Shared/_Imports.razor`. Add the same usings to a folder when you migrate its pages; move them to the root `_Imports.razor` once Radzen is removed.
+- Theme: `wwwroot/css/theme.css` holds the Blueprint CSS variables for light (`:root`) and dark (`.dark`). The "bridge" section at the end of `wwwroot/css/app.css` maps the Radzen theme variables onto them and undoes Bootstrap's global link and list styles in the sidebar; delete it when Bootstrap and Radzen are gone.
+- There is no Tailwind build: `blazorblueprint.css` only contains `bb:`-prefixed utilities used by the components, so layout CSS for our own markup goes in scoped `.razor.css` files.
+- **Blazor-Analytics** (Google Analytics ID hard-coded in `Program.cs`).
 - Logging: **Serilog** configured from `appsettings.json`; rolling file sink writes to `logs/log-reqifviewer-*.txt`. Use `Log.ForContext<T>()` rather than injecting `ILogger` (this is the established pattern).
 - The Dockerfile runs as a non-root user (`$APP_UID`) on Alpine; anything that needs to write must go under `/app` (e.g. `/app/logs`, which is created in the image).
 

reqifviewer.Tests/HostingTestFixture.cs

@@ -0,0 +1,91 @@
+// -------------------------------------------------------------------------------------------------
+// <copyright file="HostingTestFixture.cs" company="Starion Group S.A.">
+//
+//   Copyright 2021-2026 Starion Group S.A.
+//
+//   Licensed under the Apache License, Version 2.0 (the "License");
+//   you may not use this file except in compliance with the License.
+//   You may obtain a copy of the License at
+//
+//       http://www.apache.org/licenses/LICENSE-2.0
+//
+//   Unless required by applicable law or agreed to in writing, software
+//   distributed under the License is distributed on an "AS IS" BASIS,
+//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//   See the License for the specific language governing permissions and
+//   limitations under the License.
+//
+// </copyright>
+// -------------------------------------------------------------------------------------------------
+
+namespace ReqifViewer.Tests
+{
+    using System.Net;
+    using System.Net.Http;
+    using System.Threading.Tasks;
+
+    using Microsoft.AspNetCore.Mvc.Testing;
+
+    using NUnit.Framework;
+
+    using reqifviewer;
+
+    /// <summary>
+    /// Starts the whole application in memory and checks the host page and the not-found page
+    /// </summary>
+    [TestFixture]
+    public class HostingTestFixture
+    {
+        private WebApplicationFactory<Program> factory;
+
+        private HttpClient client;
+
+        [OneTimeSetUp]
+        public void OneTimeSetUp()
+        {
+            this.factory = new WebApplicationFactory<Program>();
+            this.client = this.factory.CreateClient(new WebApplicationFactoryClientOptions { AllowAutoRedirect = false });
+        }
+
+        [OneTimeTearDown]
+        public void OneTimeTearDown()
+        {
+            this.client.Dispose();
+            this.factory.Dispose();
+        }
+
+        [Test]
+        public async Task Verify_that_the_root_returns_the_host_page()
+        {
+            var response = await this.client.GetAsync("/");
+            var html = await response.Content.ReadAsStringAsync();
+
+            Assert.That(response.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+            Assert.That(html, Does.Contain("_framework/blazor.web.js"));
+            Assert.That(html, Does.Contain("ReqIF Viewer"));
+        }
+
+        [Test]
+        public async Task Verify_that_the_theme_is_loaded_before_the_Blazor_Blueprint_stylesheet()
+        {
+            var html = await this.client.GetStringAsync("/");
+
+            var theme = html.IndexOf("css/theme.", System.StringComparison.Ordinal);
+            var blueprint = html.IndexOf("blazorblueprint.css", System.StringComparison.Ordinal);
+
+            Assert.That(theme, Is.GreaterThanOrEqualTo(0), "theme.css is not referenced");
+            Assert.That(blueprint, Is.GreaterThan(theme), "theme.css must be loaded before blazorblueprint.css");
+        }
+
+        [Test]
+        public async Task Verify_that_an_unknown_address_returns_the_not_found_page()
+        {
+            var response = await this.client.GetAsync("/this-page-does-not-exist");
+            var html = await response.Content.ReadAsStringAsync();
+
+            Assert.That(response.StatusCode, Is.EqualTo(HttpStatusCode.NotFound));
+            Assert.That(html, Does.Contain("Sorry, there&#x27;s nothing at this address.").Or.Contain("Sorry, there's nothing at this address."));
+            Assert.That(html, Does.Contain("_framework/blazor.web.js"), "the not-found page is rendered inside the app");
+        }
+    }
+}

reqifviewer.Tests/ReqIFExtensions/SpecElementWithAttributesExtensionTestFixture.cs

@@ -71,5 +71,39 @@ public void Verify_that_ExtractSpecificationName_returns_expected_result()
             specObject = this.reqIf.CoreContent.SpecObjects.Single(x => x.Identifier == "_DqMpsKddEeafNduaIhMwQg");
             Assert.That(specObject.ExtractDisplayName(), Is.EqualTo("REQ-6"));
         }
+
+        [Test]
+        public void Verify_that_ExtractDisplayText_returns_plain_text_in_the_same_order_as_ExtractDisplayName()
+        {
+            // The first attribute value is XHTML: its text is returned without markup
+            var specObject = this.reqIf.CoreContent.SpecObjects.Single(x => x.Identifier == "_o7scQ6dbEeafNduaIhMwQg");
+            Assert.That(specObject.ExtractDisplayText(), Is.EqualTo("Stakeholder Requirements"));
+
+            var specification = this.reqIf.CoreContent.Specifications.Single(x => x.Identifier == "_o7scS6dbEeafNduaIhMwQg");
+            Assert.That(specification.ExtractDisplayText(), Is.EqualTo("Requirements Document"));
+
+            specObject = this.reqIf.CoreContent.SpecObjects.Single(x => x.Identifier == "_DqMpsKddEeafNduaIhMwQg");
+            Assert.That(specObject.ExtractDisplayText(), Is.EqualTo("REQ-6"));
+        }
+
+        [Test]
+        public void Verify_that_ExtractDisplayText_falls_back_to_the_identifier()
+        {
+            var withoutValues = new Specification { Identifier = "spec-1" };
+            Assert.That(withoutValues.ExtractDisplayText(), Is.EqualTo("spec-1"));
+
+            var withEmptyXhtml = new SpecObject { Identifier = "object-1" };
+            withEmptyXhtml.Values.Add(new AttributeValueXHTML { TheValue = "<xhtml:div xmlns:xhtml=\"http://www.w3.org/1999/xhtml\">  </xhtml:div>" });
+            Assert.That(withEmptyXhtml.ExtractDisplayText(), Is.EqualTo("object-1"));
+        }
+
+        [Test]
+        public void Verify_that_ExtractDisplayText_collapses_whitespace()
+        {
+            var specObject = new SpecObject { Identifier = "object-1" };
+            specObject.Values.Add(new AttributeValueXHTML { TheValue = "<xhtml:div xmlns:xhtml=\"http://www.w3.org/1999/xhtml\">\n  First   line\n  <xhtml:b>bold</xhtml:b>\n</xhtml:div>" });
+
+            Assert.That(specObject.ExtractDisplayText(), Is.EqualTo("First line bold"));
+        }
     }
 }

reqifviewer.Tests/Shared/MainLayoutTestFixture.cs

@@ -0,0 +1,172 @@
+// -------------------------------------------------------------------------------------------------
+// <copyright file="MainLayoutTestFixture.cs" company="Starion Group S.A.">
+//
+//   Copyright 2021-2026 Starion Group S.A.
+//
+//   Licensed under the Apache License, Version 2.0 (the "License");
+//   you may not use this file except in compliance with the License.
+//   You may obtain a copy of the License at
+//
+//       http://www.apache.org/licenses/LICENSE-2.0
+//
+//   Unless required by applicable law or agreed to in writing, software
+//   distributed under the License is distributed on an "AS IS" BASIS,
+//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//   See the License for the specific language governing permissions and
+//   limitations under the License.
+//
+// </copyright>
+// -------------------------------------------------------------------------------------------------
+
+namespace ReqifViewer.Tests.Shared
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Linq;
+    using System.Net;
+    using System.Net.Http;
+    using System.Threading;
+    using System.Threading.Tasks;
+
+    using BlazorBlueprint.Components;
+
+    using Bunit;
+    using Bunit.TestDoubles;
+
+    using Microsoft.AspNetCore.Components;
+    using Microsoft.Extensions.DependencyInjection;
+
+    using Moq;
+
+    using NUnit.Framework;
+
+    using Radzen;
+
+    using ReqIFSharp;
+    using ReqIFSharp.Extensions.Services;
+
+    using reqifviewer.Pages.Index;
+    using reqifviewer.Shared;
+
+    using TestContext = Bunit.TestContext;
+
+    /// <summary>
+    /// Suite of tests for the <see cref="MainLayout"/> component
+    /// </summary>
+    [TestFixture]
+    public class MainLayoutTestFixture
+    {
+        private TestContext context;
+
+        [SetUp]
+        public void SetUp()
+        {
+            this.context = new TestContext();
+            this.context.JSInterop.Mode = JSRuntimeMode.Loose;
+            this.context.Services.AddBlazorBlueprintComponents();
+
+            this.context.Services.AddScoped<Radzen.DialogService>();
+
+            // The About dialog downloads the license text; answer it without going to the network
+            this.context.Services.AddSingleton(new HttpClient(new StubHttpMessageHandler()));
+            this.context.Services.AddScoped<NotificationService>();
+            this.context.Services.AddScoped<TooltipService>();
+            this.context.Services.AddScoped<ContextMenuService>();
+
+            var reqIfLoaderService = new Mock<IReqIFLoaderService>();
+            reqIfLoaderService.Setup(x => x.ReqIFData).Returns([]);
+            this.context.Services.AddSingleton(reqIfLoaderService.Object);
+        }
+
+        [TearDown]
+        public void TearDown()
+        {
+            this.context.Dispose();
+        }
+
+        /// <summary>
+        /// Answers every request with a short text, so components that download files do not reach the network
+        /// </summary>
+        private sealed class StubHttpMessageHandler : HttpMessageHandler
+        {
+            protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+            {
+                return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("license text") });
+            }
+        }
+
+        private IRenderedComponent<MainLayout> RenderLayout()
+        {
+            return this.context.RenderComponent<MainLayout>(parameters => parameters.Add(x => x.Body, (RenderFragment)(builder => builder.AddContent(0, "page content"))));
+        }
+
+        [Test]
+        public void Verify_that_MainLayout_renders_the_page_body()
+        {
+            var renderer = this.RenderLayout();
+
+            Assert.That(renderer.Find("main.app-content").TextContent, Does.Contain("page content"));
+        }
+
+        [Test]
+        public void Verify_that_About_button_opens_the_About_dialog()
+        {
+            string openedTitle = null;
+            Type openedType = null;
+
+            var renderer = this.RenderLayout();
+
+            this.context.Services.GetRequiredService<Radzen.DialogService>().OnOpen += (title, type, _, _) =>
+            {
+                openedTitle = title;
+                openedType = type;
+            };
+
+            renderer.FindAll("header button").Single(x => x.TextContent.Trim() == "About").Click();
+
+            Assert.That(openedTitle, Is.EqualTo("About ReqIF Viewer"));
+            Assert.That(openedType, Is.EqualTo(typeof(AboutComponent)));
+        }
+
+        [Test]
+        public void Verify_that_the_GitHub_link_opens_in_a_new_tab_without_opener_or_referrer()
+        {
+            var renderer = this.RenderLayout();
+
+            var link = renderer.Find("a[href=\"https://github.com/STARIONGROUP/reqifviewer\"]");
+
+            Assert.That(link.GetAttribute("target"), Is.EqualTo("_blank"));
+            Assert.That(link.GetAttribute("rel")?.Split(' '), Is.SupersetOf(new[] { "noopener", "noreferrer" }));
+        }
+
+        [Test]
+        public void Verify_that_the_mobile_sidebar_closes_after_navigating()
+        {
+            var renderer = this.RenderLayout();
+            var provider = renderer.FindComponent<BbSidebarProvider>();
+
+            Assert.That(provider.Instance.OpenMobile, Is.False);
+
+            // The user opens the drawer on a small screen
+            renderer.InvokeAsync(() => provider.Instance.OpenMobileChanged.InvokeAsync(true)).GetAwaiter().GetResult();
+            renderer.Render();
+            Assert.That(renderer.FindComponent<BbSidebarProvider>().Instance.OpenMobile, Is.True);
+
+            // ... and follows a link
+            this.context.Services.GetRequiredService<FakeNavigationManager>().NavigateTo("reqifstatistics/doc-a");
+
+            renderer.WaitForAssertion(() => Assert.That(renderer.FindComponent<BbSidebarProvider>().Instance.OpenMobile, Is.False));
+        }
+
+        [Test]
+        public void Verify_that_MainLayout_stops_listening_to_navigation_when_disposed()
+        {
+            this.RenderLayout();
+            this.context.DisposeComponents();
+
+            var navigationManager = this.context.Services.GetRequiredService<FakeNavigationManager>();
+
+            Assert.DoesNotThrow(() => navigationManager.NavigateTo("reqifstatistics/doc-a"));
+        }
+    }
+}