using Bunit;
using Microsoft.AspNetCore.Components;
using Microsoft.Extensions.DependencyInjection;
using NSubstitute;
using ZB.MOM.WW.ScadaBridge.CentralUI.Components.Shared;
using ZB.MOM.WW.ScadaBridge.CentralUI.Services;

namespace ZB.MOM.WW.ScadaBridge.CentralUI.Tests.Shared;

/// <summary>
/// bUnit tests for the <see cref="MoveDataConnectionDialog"/> (M9-T24b). The dialog
/// surfaces a target-site picker (excluding the connection's current site) and, on
/// confirm, dispatches a <c>MoveDataConnectionCommand</c> through the management
/// path via <see cref="IDataConnectionMoveService"/> — the SAME guard-running seam
/// the server uses. A guard error must be shown inline and the dialog must stay open;
/// a success must close the dialog and raise the refresh signal.
///
/// The service is substituted so the tests capture the dispatched (connectionId,
/// targetSiteId) and simulate both a success and a guard-error response without a
/// real ManagementActor in scope.
/// </summary>
public class MoveDataConnectionDialogTests : BunitContext
{
    private readonly IDataConnectionMoveService _service = Substitute.For<IDataConnectionMoveService>();

    public MoveDataConnectionDialogTests()
    {
        Services.AddSingleton(_service);
    }

    private IRenderedComponent<MoveDataConnectionDialog> RenderDialog(
        int connectionId = 100,
        string connectionName = "PLC-1",
        bool visible = true,
        IEnumerable<(int Id, string Label)>? siteOptions = null,
        EventCallback? onMoved = null,
        EventCallback<bool>? visibleChanged = null)
    {
        siteOptions ??= new[] { (2, "Plant-B"), (3, "Plant-C") };
        return Render<MoveDataConnectionDialog>(p => p
            .Add(d => d.IsVisible, visible)
            .Add(d => d.ConnectionId, connectionId)
            .Add(d => d.ConnectionName, connectionName)
            .Add(d => d.SiteOptions, siteOptions)
            .Add(d => d.OnMoved, onMoved ?? default)
            .Add(d => d.IsVisibleChanged, visibleChanged ?? default));
    }

    [Fact]
    public void Visible_RendersTargetSitePicker_WithSuppliedOptions()
    {
        // (a) The dialog opens with a site picker whose options are exactly the
        // supplied target sites (the page excludes the connection's current site).
        var cut = RenderDialog(siteOptions: new[] { (2, "Plant-B"), (3, "Plant-C") });

        var options = cut.FindAll("select option");
        Assert.Contains(options, o => o.TextContent.Contains("Plant-B"));
        Assert.Contains(options, o => o.TextContent.Contains("Plant-C"));
        // Picker reflects the connection name in the header.
        Assert.Contains("PLC-1", cut.Markup);
    }

    [Fact]
    public void Hidden_RendersNothing()
    {
        var cut = RenderDialog(visible: false);
        Assert.Empty(cut.Markup.Trim());
    }

    [Fact]
    public void Confirm_DispatchesMoveCommand_WithConnectionAndTargetSiteIds()
    {
        // (b) Confirming dispatches the move through the management-dispatch service
        // with the connection id + the selected target site id.
        _service.MoveAsync(Arg.Any<int>(), Arg.Any<int>(), Arg.Any<CancellationToken>())
            .Returns(Task.FromResult(DataConnectionMoveResult.Ok()));

        var cut = RenderDialog(connectionId: 100, siteOptions: new[] { (2, "Plant-B"), (3, "Plant-C") });

        // Pick Plant-C (id 3) and confirm.
        cut.Find("select").Change("3");
        cut.FindAll("button").First(b => b.TextContent.Contains("Move")).Click();

        _service.Received(1).MoveAsync(100, 3, Arg.Any<CancellationToken>());
    }

    [Fact]
    public void GuardError_IsShownInline_AndDialogStaysOpen()
    {
        // (c) A guard-error response is rendered inline and the dialog does NOT close
        // (IsVisibleChanged is not raised with false; OnMoved is not raised).
        const string guardError =
            "Cannot move data connection 'PLC-1' (ID 100): it is referenced by 1 instance binding(s).";
        _service.MoveAsync(Arg.Any<int>(), Arg.Any<int>(), Arg.Any<CancellationToken>())
            .Returns(Task.FromResult(DataConnectionMoveResult.Fail(guardError)));

        var closed = false;
        var moved = false;
        var cut = RenderDialog(
            connectionId: 100,
            siteOptions: new[] { (2, "Plant-B") },
            onMoved: EventCallback.Factory.Create(this, () => moved = true),
            visibleChanged: EventCallback.Factory.Create<bool>(this, v => { if (!v) closed = true; }));

        cut.Find("select").Change("2");
        cut.FindAll("button").First(b => b.TextContent.Contains("Move")).Click();

        Assert.Contains(guardError, cut.Markup);
        Assert.False(closed, "Dialog must stay open on a guard error.");
        Assert.False(moved, "OnMoved must not fire on a guard error.");
    }

    [Fact]
    public void Success_ClosesDialog_AndRaisesRefreshSignal()
    {
        _service.MoveAsync(Arg.Any<int>(), Arg.Any<int>(), Arg.Any<CancellationToken>())
            .Returns(Task.FromResult(DataConnectionMoveResult.Ok()));

        var closed = false;
        var moved = false;
        var cut = RenderDialog(
            connectionId: 100,
            siteOptions: new[] { (2, "Plant-B") },
            onMoved: EventCallback.Factory.Create(this, () => moved = true),
            visibleChanged: EventCallback.Factory.Create<bool>(this, v => { if (!v) closed = true; }));

        cut.Find("select").Change("2");
        cut.FindAll("button").First(b => b.TextContent.Contains("Move")).Click();

        Assert.True(closed, "Dialog must close on success.");
        Assert.True(moved, "OnMoved must fire on success to refresh the tree.");
    }
}