Extract hard-coded routes into centralized constants (resolves #747)

EssentialCSharp.Web.Tests/SitemapXmlHelpersTests.cs

@@ -246,6 +246,72 @@ public async Task GenerateSitemapXml_DoesNotSetLastModifiedDateWhenSiteMappingDa
         await Assert.That(siteMappingNode.LastModificationDate).IsNull();
     }
 
+    [Test]
+    public async Task GenerateSitemapXml_GuidelinesRoute_HasHighPriority()
+    {
+        // Arrange
+        var siteMappings = new List<SiteMapping>();
+        var baseUrl = "https://test.example.com/";
+
+        // Act
+        var routeConfigurationService = Factory.Services.GetRequiredService<IRouteConfigurationService>();
+        SitemapXmlHelpers.GenerateSitemapXml(
+            siteMappings,
+            routeConfigurationService,
+            baseUrl,
+            out var nodes);
+
+        // Assert — /guidelines should have priority 0.9 (higher than default 0.5)
+        var guidelinesNode = nodes.FirstOrDefault(n => n.Url.Contains("/guidelines", StringComparison.OrdinalIgnoreCase));
+        await Assert.That(guidelinesNode).IsNotNull();
+        await Assert.That(guidelinesNode!.Priority).IsEqualTo(0.9M);
+        await Assert.That(guidelinesNode.ChangeFrequency).IsEqualTo(ChangeFrequency.Monthly);
+    }
+
+    [Test]
+    public async Task GenerateSitemapXml_TermsOfServiceRoute_HasYearlyFrequencyAndLowPriority()
+    {
+        // Arrange
+        var siteMappings = new List<SiteMapping>();
+        var baseUrl = "https://test.example.com/";
+
+        // Act
+        var routeConfigurationService = Factory.Services.GetRequiredService<IRouteConfigurationService>();
+        SitemapXmlHelpers.GenerateSitemapXml(
+            siteMappings,
+            routeConfigurationService,
+            baseUrl,
+            out var nodes);
+
+        // Assert — /termsofservice changes rarely (Yearly) and has low priority (0.2)
+        var tosNode = nodes.FirstOrDefault(n => n.Url.Contains("/termsofservice", StringComparison.OrdinalIgnoreCase));
+        await Assert.That(tosNode).IsNotNull();
+        await Assert.That(tosNode!.Priority).IsEqualTo(0.2M);
+        await Assert.That(tosNode.ChangeFrequency).IsEqualTo(ChangeFrequency.Yearly);
+    }
+
+    [Test]
+    public async Task GenerateSitemapXml_UnknownRoute_UsesDefaultSeoValues()
+    {
+        // Arrange
+        var siteMappings = new List<SiteMapping> { CreateSiteMapping(1, 1, true, "test-page-unknown-route") };
+        var baseUrl = "https://test.example.com/";
+
+        // Act
+        var routeConfigurationService = Factory.Services.GetRequiredService<IRouteConfigurationService>();
+        SitemapXmlHelpers.GenerateSitemapXml(
+            siteMappings,
+            routeConfigurationService,
+            baseUrl,
+            out var nodes);
+
+        // Assert — content pages without specific config get default SEO values
+        var contentNode = nodes.FirstOrDefault(n => n.Url.Contains("test-page-unknown-route", StringComparison.OrdinalIgnoreCase));
+        await Assert.That(contentNode).IsNotNull();
+        await Assert.That(contentNode!.Priority).IsEqualTo(0.5M);
+        await Assert.That(contentNode.ChangeFrequency).IsEqualTo(ChangeFrequency.Monthly);
+    }
+
     private static SiteMapping CreateSiteMapping(
         int chapterNumber,
         int pageNumber,

EssentialCSharp.Web/Constants/RouteConstants.cs

@@ -0,0 +1,59 @@
+using System.Collections.Frozen;
+using DotnetSitemapGenerator;
+
+namespace EssentialCSharp.Web.Constants;
+
+/// <summary>
+/// Centralized definition of application routes and their metadata.
+/// This is the single source of truth for static page route paths.
+/// Update these whenever a static page is added, removed, or renamed.
+/// </summary>
+public static class RouteConstants
+{
+    /// <summary>
+    /// Static page routes that are not content pages (e.g., informational, utility pages).
+    /// Content pages are dynamically discovered from sitemap.json.
+    /// </summary>
+    public static class StaticPages
+    {
+        public const string Home = "/home";
+        public const string About = "/about";
+        public const string Guidelines = "/guidelines";
+        public const string Announcements = "/announcements";
+        public const string TermsOfService = "/termsofservice";
+    }
+
+    /// <summary>
+    /// Immutable set of non-content route paths. Use to determine if a requested path
+    /// is a static page (non-content) rather than a content page (from sitemap).
+    /// </summary>
+    public static readonly FrozenSet<string> NonContentRoutes = new HashSet<string>(StringComparer.OrdinalIgnoreCase)
+    {
+        StaticPages.Home,
+        StaticPages.About,
+        StaticPages.Guidelines,
+        StaticPages.Announcements,
+        StaticPages.TermsOfService
+    }.ToFrozenSet(StringComparer.OrdinalIgnoreCase);
+
+    /// <summary>
+    /// SEO metadata for static routes used in sitemap.xml generation.
+    /// </summary>
+    public static class SeoMetadata
+    {
+        /// <summary>
+        /// Immutable map of route paths to (ChangeFrequency, Priority) tuples.
+        /// Keys include the leading slash (e.g. "/home") to match how ASP.NET Core
+        /// exposes routes. Priority is 0.0–1.0; 0.5 is the sitemap default.
+        /// </summary>
+        public static readonly FrozenDictionary<string, (ChangeFrequency Frequency, decimal Priority)> RouteConfig =
+            new Dictionary<string, (ChangeFrequency, decimal)>(StringComparer.OrdinalIgnoreCase)
+            {
+                { StaticPages.Home,          (ChangeFrequency.Monthly, 0.5m) },
+                { StaticPages.About,         (ChangeFrequency.Monthly, 0.5m) },
+                { StaticPages.Guidelines,    (ChangeFrequency.Monthly, 0.9m) },
+                { StaticPages.Announcements, (ChangeFrequency.Monthly, 0.5m) },
+                { StaticPages.TermsOfService,(ChangeFrequency.Yearly,  0.2m) }
+            }.ToFrozenDictionary(StringComparer.OrdinalIgnoreCase);
+    }
+}

EssentialCSharp.Web/Controllers/HomeController.cs

@@ -1,4 +1,5 @@
 using DotnetSitemapGenerator;
+using EssentialCSharp.Web.Constants;
 using EssentialCSharp.Web.Extensions;
 using EssentialCSharp.Web.Helpers;
 using EssentialCSharp.Web.Models;
@@ -48,35 +49,35 @@ public IActionResult Index()
         }
     }
 
-    [Route("/TermsOfService",
+    [Route(RouteConstants.StaticPages.TermsOfService,
        Name = "TermsOfService")]
     public IActionResult TermsOfService()
     {
         ViewBag.PageTitle = "Terms Of Service";
         return View();
     }
 
-    [Route("/Announcements", Name = "Announcements")]
+    [Route(RouteConstants.StaticPages.Announcements, Name = "Announcements")]
     public IActionResult Announcements()
     {
         ViewBag.PageTitle = "Announcements";
         return View();
     }
 
-    [Route("/about", Name = "about")]
+    [Route(RouteConstants.StaticPages.About, Name = "about")]
     public IActionResult About()
     {
         ViewBag.PageTitle = "About";
         return View();
     }
 
-    [Route("/home", Name = "home")]
+    [Route(RouteConstants.StaticPages.Home, Name = "home")]
     public IActionResult Home()
     {
         return View();
     }
 
-    [Route("/guidelines", Name = "guidelines")]
+    [Route(RouteConstants.StaticPages.Guidelines, Name = "guidelines")]
     public IActionResult Guidelines()
     {
         ViewBag.PageTitle = "Coding Guidelines";

EssentialCSharp.Web/Helpers/SitemapXmlHelpers.cs

@@ -1,4 +1,5 @@
 using DotnetSitemapGenerator;
+using EssentialCSharp.Web.Constants;
 using EssentialCSharp.Web.Services;
 
 namespace EssentialCSharp.Web.Helpers;
@@ -74,26 +75,22 @@ private static bool IsSitemapRoute(string route) =>
 
     private static ChangeFrequency GetChangeFrequencyForRoute(string route)
     {
-        return route.ToLowerInvariant() switch
+        if (RouteConstants.SeoMetadata.RouteConfig.TryGetValue(route, out var config))
         {
-            "/termsofservice" => ChangeFrequency.Yearly,
-            "/announcements" => ChangeFrequency.Monthly,
-            "/guidelines" => ChangeFrequency.Monthly,
-            _ => ChangeFrequency.Monthly
-        };
+            return config.Frequency;
+        }
+
+        return ChangeFrequency.Monthly;
     }
 
     private static decimal GetPriorityForRoute(string route)
     {
-        return route.ToLowerInvariant() switch
+        if (RouteConstants.SeoMetadata.RouteConfig.TryGetValue(route, out var config))
         {
-            "/home" => 0.5M,
-            "/about" => 0.5M,
-            "/announcements" => 0.5M,
-            "/guidelines" => 0.9M,
-            "/termsofservice" => 0.2M,
-            _ => 0.5M
-        };
+            return config.Priority;
+        }
+
+        return 0.5M;
     }
 
 }

EssentialCSharp.Web/Views/Home/Home.cshtml

@@ -122,7 +122,7 @@
 
     <div class="row justify-content-center">
         <div class="col-auto">
-            <a class="btn btn-primary" href="/Announcements">
+            <a class="btn btn-primary" href="/announcements">
                 View All Announcements
             </a>
         </div>

EssentialCSharp.Web/src/components/SidebarPanel.vue

@@ -1,35 +1,11 @@
 <script setup>
 import { inject } from "vue";
 import TocTree from "./TocTree.vue";
+import { NAVIGATION_LINKS } from "../constants/routes.js";
 
 const shell = inject("shell");
 const currentPath = window.location.pathname.toLowerCase();
-const navLinks = [
-    {
-        href: "/home",
-        iconClass: "fas fa-home me-2",
-        label: "Home",
-        activePaths: ["/", "/home"]
-    },
-    {
-        href: "/about",
-        iconClass: "fas fa-book me-2",
-        label: "About",
-        activePaths: ["/about"]
-    },
-    {
-        href: "/guidelines",
-        iconClass: "fas fa-code me-2",
-        label: "Guidelines",
-        activePaths: ["/guidelines"]
-    },
-    {
-        href: "/announcements",
-        iconClass: "fas fa-bullhorn me-2",
-        label: "Announcements",
-        activePaths: ["/announcements"]
-    }
-];
+const navLinks = NAVIGATION_LINKS;
 
 function isActivePath(paths) {
     return paths.includes(currentPath);
@@ -66,7 +42,7 @@ function isActivePath(paths) {
                 <div class="list-group list-group-flush d-md-none mb-3">
                     <a
                         v-for="navLink in navLinks"
-                        :key="navLink.href"
+                        :key="navLink.key"
                         :href="navLink.href"
                         class="list-group-item list-group-item-action"
                         :class="{ active: isActivePath(navLink.activePaths) }"

EssentialCSharp.Web/src/composables/useSiteShell.js

@@ -1,5 +1,6 @@
 import { computed, nextTick, onMounted, onUnmounted, reactive, ref, watch } from "vue";
 import { useWindowSize } from "./useWindowSize.js";
+import { isContentPagePath } from "../constants/routes.js";
 
 const SMALL_SCREEN_SIZE = 768;
 
@@ -71,7 +72,15 @@ export function useSiteShell() {
     const smallScreen = computed(() => (windowWidth.value || 0) < SMALL_SCREEN_SIZE);
     const currentPage = findCurrentPage([], tocData) ?? [];
     const chapterParentPage = currentPage.find((parent) => parent.level === 0) ?? null;
-    const isContentPage = computed(() => percentComplete.value !== null);
+
+    /**
+     * Determines if the current page is a content page (from sitemap) or a static page.
+     * Checks against the NON_CONTENT_ROUTES array via isContentPagePath and falls back
+     * to percentComplete check for additional verification that content data is loaded.
+     */
+    const isContentPage = computed(() => {
+        return isContentPagePath(window.location.pathname) && percentComplete.value !== null;
+    });
 
     for (const item of currentPage) {
         expandedTocs.add(item.key);

EssentialCSharp.Web/src/constants/routes.js

@@ -0,0 +1,76 @@
+/**
+ * Centralized route constants for the frontend.
+ * Mirrors the backend RouteConstants to ensure consistency across frontend and backend.
+ * Update these whenever routes are added, removed, or changed.
+ */
+
+export const ROUTES = {
+    HOME: '/home',
+    ABOUT: '/about',
+    GUIDELINES: '/guidelines',
+    ANNOUNCEMENTS: '/announcements',
+    TERMS_OF_SERVICE: '/termsofservice'
+};
+
+/**
+ * Array of non-content route paths.
+ * Use with Array.includes() to determine if a path is a static page vs. a content page.
+ */
+export const NON_CONTENT_ROUTES = [
+    ROUTES.HOME,
+    ROUTES.ABOUT,
+    ROUTES.GUIDELINES,
+    ROUTES.ANNOUNCEMENTS,
+    ROUTES.TERMS_OF_SERVICE
+];
+
+/**
+ * Navigation link definitions for the sidebar.
+ * Each link includes href, label, icon class, and active path matching patterns.
+ * Note: ROUTES.TERMS_OF_SERVICE is intentionally excluded from this list —
+ * it is a legal page linked in the footer, not a primary navigation destination.
+ */
+export const NAVIGATION_LINKS = [
+    {
+        href: ROUTES.HOME,
+        label: 'Home',
+        iconClass: 'fas fa-home me-2',
+        activePaths: ['/', ROUTES.HOME],
+        key: 'home'
+    },
+    {
+        href: ROUTES.ABOUT,
+        label: 'About',
+        iconClass: 'fas fa-book me-2',
+        activePaths: [ROUTES.ABOUT],
+        key: 'about'
+    },
+    {
+        href: ROUTES.GUIDELINES,
+        label: 'Guidelines',
+        iconClass: 'fas fa-code me-2',
+        activePaths: [ROUTES.GUIDELINES],
+        key: 'guidelines'
+    },
+    {
+        href: ROUTES.ANNOUNCEMENTS,
+        label: 'Announcements',
+        iconClass: 'fas fa-bullhorn me-2',
+        activePaths: [ROUTES.ANNOUNCEMENTS],
+        key: 'announcements'
+    }
+];
+
+/**
+ * Determines if the given path is a content page (from sitemap)
+ * versus a static page (non-content).
+ * @param {string} path - The path to check
+ * @returns {boolean} - True if path is a content page, false if static page
+ */
+export function isContentPagePath(path) {
+    const normalizedPath = path.toLowerCase();
+    return !NON_CONTENT_ROUTES.some(route => 
+        normalizedPath === route.toLowerCase() || 
+        normalizedPath.startsWith(route.toLowerCase() + '/')
+    );
+}