Add error page.

Shogi.UI/Pages/Authentication.razor

@@ -1,10 +1,23 @@
 @page "/authentication/{action}"
 @using Microsoft.AspNetCore.Components.WebAssembly.Authentication
+@inject NavigationManager navigationManager
 
-<RemoteAuthenticatorView Action="@Action" />
+<RemoteAuthenticatorView Action="@Action" LogInFailed="LoginFailed">
+</RemoteAuthenticatorView>
 @code {
     [Parameter] public string? Action { get; set; }
     // https://github.com/dotnet/aspnetcore/blob/main/src/Components/WebAssembly/WebAssembly.Authentication/src/Models/RemoteAuthenticationActions.cs
     // https://github.com/dotnet/aspnetcore/blob/7c810658463f35c39c54d5fb8a8dbbfd463bf747/src/Components/WebAssembly/WebAssembly.Authentication/src/RemoteAuthenticatorViewCore.cs
+
+    RenderFragment LoginFailed(string message)
+    {
+        Console.WriteLine($"Failed to login because: {message}");
+        if (message.Contains("AADSTS65004", StringComparison.OrdinalIgnoreCase))
+        {
+            return builder => navigationManager.NavigateTo("/");
+        }
+        return builder => navigationManager.NavigateTo("/error");
+    }
+
 }
 

Shogi.UI/Pages/FancyErrorPage.razor

@@ -0,0 +1,17 @@
+@page "/error"
+
+<main>
+    <div class="card">
+        <div class="card-body">
+            <h1 class="card-title">Oops!</h1>
+            <p class="card-text">Something went wrong.</p>
+            <p class="card-text">
+                <a href="/">Return to the home page</a>
+            </p>
+        </div>
+    </div>
+</main>
+
+@code {
+
+}

Shogi.UI/Pages/FancyErrorPage.razor.css

@@ -0,0 +1,4 @@
+main {
+    display: grid;
+    place-content: center;
+}

Shogi.UI/Pages/Home/Account/AccountManager.cs

@@ -123,7 +123,7 @@ public class AccountManager
         else if (platform == WhichAccountPlatform.Microsoft)
         {
             await accountState.SetUser(null);
-            navigation.NavigateToLogout("authentication/logout", "https://lucaserver.space/shogi");
+            navigation.NavigateToLogout("authentication/logout");
         }
     }
 }

Shogi.UI/Pages/Home/Api/MsalMessageHandler.cs

@@ -11,7 +11,7 @@ namespace Shogi.UI.Pages.Home.Api
                     authorizedUrls: new[] { "https://api.lucaserver.space/Shogi.Api", "https://localhost:5001" },
                     scopes: new string[] {
                         "api://c1e94676-cab0-42ba-8b6c-9532b8486fff/DefaultScope",
-                        "offline_access",
+                        //"offline_access",
                     });
         }