[Parallelizable(ParallelScope.Self)]
[TestFixture]
public class BlazorUITests : PageTest
{
    private DistributedApplication? _app;
    private string? _blazorUrl;

    [OneTimeSetUp]
    public async Task OneTimeSetUp()
    {
        var appHost = await DistributedApplicationTestingBuilder
            .CreateAsync<Projects.Sorcha_AppHost>();
        _app = await appHost.BuildAsync();
        await _app.StartAsync();
        _blazorUrl = _app.GetEndpoint("blazor-client").ToString();
    }

    [Test]
    public async Task HomePage_LoadsSuccessfully()
    {
        await Page.GotoAsync(_blazorUrl!);
        await Page.WaitForLoadStateAsync();
        await Expect(Page).ToHaveTitleAsync(new Regex("Sorcha|Blueprint"));
    }
}

// Role-based (preferred)
await Page.GetByRole(AriaRole.Button, new() { Name = "Submit" }).ClickAsync();

// Text-based
Page.Locator("a:has-text('Designer')")

// MudBlazor components
Page.Locator(".mud-button")
Page.Locator(".mud-table")

// Test IDs (most stable)
Page.Locator("[data-testid='my-element']")

[Test]
public async Task NoJavaScriptErrors()
{
    var errors = new List<string>();
    Page.Console += (_, msg) =>
    {
        if (msg.Type == "error") errors.Add(msg.Text);
    };

    await Page.GotoAsync(_blazorUrl!);
    await Page.WaitForLoadStateAsync();
    
    var criticalErrors = errors.Where(e =>
        !e.Contains("WASM") && !e.Contains("Blazor")).ToList();
    Assert.That(criticalErrors, Is.Empty);
}

[Test]
public async Task ResponsiveDesign_Works()
{
    await Page.SetViewportSizeAsync(375, 667); // Mobile
    await Page.GotoAsync(_blazorUrl!);
    Assert.That(await Page.TextContentAsync("body"), Is.Not.Empty);

    await Page.SetViewportSizeAsync(1920, 1080); // Desktop
    await Page.ReloadAsync();
    Assert.That(await Page.TextContentAsync("body"), Is.Not.Empty);
}