Add .NET 8 templated projects.

Aaru.Server.New/Components/Account/IdentityRedirectManager.cs

@@ -0,0 +1,60 @@
+using System.Diagnostics.CodeAnalysis;
+using Microsoft.AspNetCore.Components;
+
+namespace Aaru.Server.New.Components.Account;
+
+internal sealed class IdentityRedirectManager(NavigationManager navigationManager)
+{
+    public const string StatusCookieName = "Identity.StatusMessage";
+
+    private static readonly CookieBuilder StatusCookieBuilder = new()
+    {
+        SameSite    = SameSiteMode.Strict,
+        HttpOnly    = true,
+        IsEssential = true,
+        MaxAge      = TimeSpan.FromSeconds(5),
+    };
+
+    [DoesNotReturn]
+    public void RedirectTo(string? uri)
+    {
+        uri ??= "";
+
+        // Prevent open redirects.
+        if(!Uri.IsWellFormedUriString(uri, UriKind.Relative))
+        {
+            uri = navigationManager.ToBaseRelativePath(uri);
+        }
+
+        // During static rendering, NavigateTo throws a NavigationException which is handled by the framework as a redirect.
+        // So as long as this is called from a statically rendered Identity component, the InvalidOperationException is never thrown.
+        navigationManager.NavigateTo(uri);
+
+        throw new
+            InvalidOperationException($"{nameof(IdentityRedirectManager)} can only be used during static rendering.");
+    }
+
+    [DoesNotReturn]
+    public void RedirectTo(string uri, Dictionary<string, object?> queryParameters)
+    {
+        var uriWithoutQuery = navigationManager.ToAbsoluteUri(uri).GetLeftPart(UriPartial.Path);
+        var newUri          = navigationManager.GetUriWithQueryParameters(uriWithoutQuery, queryParameters);
+        RedirectTo(newUri);
+    }
+
+    [DoesNotReturn]
+    public void RedirectToWithStatus(string uri, string message, HttpContext context)
+    {
+        context.Response.Cookies.Append(StatusCookieName, message, StatusCookieBuilder.Build(context));
+        RedirectTo(uri);
+    }
+
+    private string CurrentPath => navigationManager.ToAbsoluteUri(navigationManager.Uri).GetLeftPart(UriPartial.Path);
+
+    [DoesNotReturn]
+    public void RedirectToCurrentPage() => RedirectTo(CurrentPath);
+
+    [DoesNotReturn]
+    public void RedirectToCurrentPageWithStatus(string message, HttpContext context) =>
+        RedirectToWithStatus(CurrentPath, message, context);
+}