using Microsoft.Playwright;
using ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests.Cluster;
using Xunit;

namespace ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests.Deployment;

/// <summary>
/// E2E coverage for the Deployment Status page's real-time, push-based update
/// model (Tier 2). The page (<c>/deployment/deployments</c>) is NOT polled: in
/// <c>OnInitializedAsync</c> it subscribes to
/// <c>IDeploymentStatusNotifier.StatusChanged</c> — a process singleton the
/// DeploymentManager raises on every deployment-record status write — and reloads
/// the table on each notification, which Blazor Server pushes to the browser over
/// its SignalR circuit. So with the page already open, a CLI <c>instance deploy</c>
/// makes the instance's row surface with no manual Refresh: the row simply
/// appearing IS the proof the push path works.
///
/// <para>
/// Each fact mints a fresh ephemeral instance on the real <c>site-a</c> (via
/// <see cref="DeploymentFixture.CreateInstanceAsync"/>) and deletes it in a
/// <c>finally</c>. The minted <c>uniqueName</c> is unique, so its row can never
/// pre-exist — the row's appearance is attributable solely to the deploy under test.
/// </para>
///
/// <para>
/// <b>Why Fact B's negative is deterministic:</b> the Pause button toggles
/// <c>_autoRefresh</c>, and <c>OnDeploymentStatusChanged</c> early-returns on
/// <c>!_autoRefresh</c>, so a paused page deterministically ignores the
/// <c>StatusChanged</c> notification. The pause click round-trips over the SignalR
/// circuit (and we wait for the button to flip to "Resume" before deploying), so
/// <c>_autoRefresh</c> is committed <c>false</c> server-side BEFORE the deploy fires
/// — the suppression is not a race. Refresh calls <c>LoadDataAsync</c> directly,
/// bypassing the pause guard, so the row surfaces on the explicit reload.
/// </para>
/// </summary>
[Collection("Playwright")]
public class DeploymentsRealtimeTests : IClassFixture<DeploymentFixture>
{
    private readonly PlaywrightFixture _pw;
    private readonly DeploymentFixture _cluster;

    public DeploymentsRealtimeTests(PlaywrightFixture pw, DeploymentFixture cluster)
    {
        _pw = pw;
        _cluster = cluster;
    }

    [SkippableFact]
    public async Task DeployingInstance_PushesRowWithoutManualRefresh()
    {
        Skip.IfNot(_cluster.Available, ClusterAvailability.SkipReason);

        var (instanceId, uniqueName) = await _cluster.CreateInstanceAsync();
        try
        {
            // Open the page FIRST so the StatusChanged subscription is live before we deploy.
            var page = await _pw.NewAuthenticatedPageAsync();
            await page.GotoAsync($"{PlaywrightFixture.BaseUrl}/deployment/deployments");
            await page.WaitForLoadStateAsync(LoadState.NetworkIdle);
            await Assertions.Expect(page.Locator("h4:has-text('Deployment Status')")).ToBeVisibleAsync();

            // Deploy over the CLI — this writes deployment records and raises StatusChanged,
            // which the page reloads on (push). No Refresh click here: the row appearing IS
            // the proof the SignalR push path works.
            await CliRunner.DeployInstanceAsync(instanceId);

            var row = page.Locator("table tbody tr", new() { HasText = uniqueName });
            await Assertions.Expect(row).ToBeVisibleAsync(new() { Timeout = 25_000 });
        }
        finally
        {
            await CliRunner.DeleteInstanceAsync(instanceId);
        }
    }

    [SkippableFact]
    public async Task PausedUpdates_SuppressPush_RefreshRestoresRow()
    {
        Skip.IfNot(_cluster.Available, ClusterAvailability.SkipReason);

        var (instanceId, uniqueName) = await _cluster.CreateInstanceAsync();
        try
        {
            var page = await _pw.NewAuthenticatedPageAsync();
            await page.GotoAsync($"{PlaywrightFixture.BaseUrl}/deployment/deployments");
            await page.WaitForLoadStateAsync(LoadState.NetworkIdle);
            // Confirm the page loaded before interacting (symmetric with Fact A) — a failed
            // load then surfaces as a clear heading-miss rather than a confusing Pause timeout.
            await Assertions.Expect(page.Locator("h4:has-text('Deployment Status')")).ToBeVisibleAsync();

            // Pause — the click round-trips over the circuit, so _autoRefresh is committed
            // false before the deploy below. The button flipping to "Resume" proves it.
            await page.Locator("button[aria-label='Pause auto-refresh']").ClickAsync();
            await Assertions.Expect(page.Locator("button[aria-label='Resume auto-refresh']"))
                .ToBeVisibleAsync(new() { Timeout = 5_000 });

            await CliRunner.DeployInstanceAsync(instanceId);

            // Paused: StatusChanged is ignored, so the row is NOT auto-added. The push chain
            // (deploy write → StatusChanged → InvokeAsync re-render → SignalR diff) completes
            // well under a second on a healthy cluster, so a 2s settle is ample to let any
            // erroneous push manifest before we assert absence. This is the one deliberate
            // fixed wait — a negative real-time assertion has no DOM event to await on the
            // "stayed absent" path. The Refresh-restores assertion below is the independent
            // positive guard if a loaded cluster ever makes this settle empirically tight.
            var row = page.Locator("table tbody tr", new() { HasText = uniqueName });
            await page.WaitForTimeoutAsync(2_000);
            await Assertions.Expect(row).ToHaveCountAsync(0);

            // Refresh bypasses the pause (LoadDataAsync) -> the row surfaces.
            await page.Locator("button[aria-label='Refresh deployments']").ClickAsync();
            await Assertions.Expect(row).ToBeVisibleAsync(new() { Timeout = 15_000 });
        }
        finally
        {
            await CliRunner.DeleteInstanceAsync(instanceId);
        }
    }
}