gui-cs.Terminal.Gui/UnitTests/Views/ToplevelTests.cs

using Xunit.Abstractions;
using static System.Net.Mime.MediaTypeNames;

namespace Terminal.Gui.ViewsTests;

public class ToplevelTests
{
    private readonly ITestOutputHelper _output;
    public ToplevelTests (ITestOutputHelper output) { _output = output; }

    [Fact]
    [AutoInitShutdown]
    public void Constructor_Default ()
    {
        var top = new Toplevel ();

        Assert.Equal (Colors.ColorSchemes ["TopLevel"], top.ColorScheme);
        Assert.Equal ("Fill(0)", top.Width.ToString ());
        Assert.Equal ("Fill(0)", top.Height.ToString ());
        Assert.False (top.Running);
        Assert.False (top.Modal);
        Assert.Null (top.MenuBar);
        Assert.Null (top.StatusBar);
        Assert.False (top.IsOverlappedContainer);
        Assert.False (top.IsOverlapped);
    }

    [Fact]
    public void Arrangement_Is_Movable ()
    {
        var top = new Toplevel ();
        Assert.Equal (ViewArrangement.Movable, top.Arrangement);
    }

#if BROKE_IN_2927
    // BUGBUG: The name of this test does not match what it does. 
    [Fact]
    [AutoInitShutdown]
    public void Application_Top_GetLocationThatFits_To_Driver_Rows_And_Cols ()
    {
        var iterations = 0;

        Application.Iteration += (s, a) =>
                                 {
                                     switch (iterations)
                                     {
                                         case 0:
                                             Assert.False (Application.Top.AutoSize);
                                             Assert.Equal ("Top1", Application.Top.Text);
                                             Assert.Equal (0, Application.Top.Frame.X);
                                             Assert.Equal (0, Application.Top.Frame.Y);
                                             Assert.Equal (Application.Driver.Cols, Application.Top.Frame.Width);
                                             Assert.Equal (Application.Driver.Rows, Application.Top.Frame.Height);

                                             Application.OnKeyPressed (new (Key.CtrlMask | Key.R));

                                             break;
                                         case 1:
                                             Assert.Equal ("Top2", Application.Top.Text);
                                             Assert.Equal (0, Application.Top.Frame.X);
                                             Assert.Equal (0, Application.Top.Frame.Y);
                                             Assert.Equal (Application.Driver.Cols, Application.Top.Frame.Width);
                                             Assert.Equal (Application.Driver.Rows, Application.Top.Frame.Height);

                                             Application.OnKeyPressed (new (Key.CtrlMask | Key.C));

                                             break;
                                         case 3:
                                             Assert.Equal ("Top1", Application.Top.Text);
                                             Assert.Equal (0, Application.Top.Frame.X);
                                             Assert.Equal (0, Application.Top.Frame.Y);
                                             Assert.Equal (Application.Driver.Cols, Application.Top.Frame.Width);
                                             Assert.Equal (Application.Driver.Rows, Application.Top.Frame.Height);

                                             Application.OnKeyPressed (new (Key.CtrlMask | Key.R));

                                             break;
                                         case 4:
                                             Assert.Equal ("Top2", Application.Top.Text);
                                             Assert.Equal (0, Application.Top.Frame.X);
                                             Assert.Equal (0, Application.Top.Frame.Y);
                                             Assert.Equal (Application.Driver.Cols, Application.Top.Frame.Width);
                                             Assert.Equal (Application.Driver.Rows, Application.Top.Frame.Height);

                                             Application.OnKeyPressed (new (Key.CtrlMask | Key.C));

                                             break;
                                         case 6:
                                             Assert.Equal ("Top1", Application.Top.Text);
                                             Assert.Equal (0, Application.Top.Frame.X);
                                             Assert.Equal (0, Application.Top.Frame.Y);
                                             Assert.Equal (Application.Driver.Cols, Application.Top.Frame.Width);
                                             Assert.Equal (Application.Driver.Rows, Application.Top.Frame.Height);

                                             Application.OnKeyPressed (new (Key.CtrlMask | Key.Q));

                                             break;
                                     }

                                     iterations++;
                                 };

        Application.Run (Top1 ());

        Toplevel Top1 ()
        {
            var top = Application.Top;
            top.Text = "Top1";

            var menu = new MenuBar (
                                    new MenuBarItem []
                                    {
                                        new MenuBarItem (
                                                         "_Options",
                                                         new MenuItem []
                                                         {
                                                             new MenuItem (
                                                                           "_Run Top2",
                                                                           "",
                                                                           () => Application.Run (Top2 ()),
                                                                           null,
                                                                           null,
                                                                           Key.CtrlMask | Key.R
                                                                          ),
                                                             new MenuItem (
                                                                           "_Quit",
                                                                           "",
                                                                           () => Application
                                                                               .RequestStop (),
                                                                           null,
                                                                           null,
                                                                           Key.CtrlMask | Key.Q
                                                                          )
                                                         }
                                                        )
                                    }
                                   );
            top.Add (menu);

            var statusBar = new StatusBar (
                                           new []
                                           {
                                               new StatusItem (
                                                               Key.CtrlMask | Key.R,
                                                               "~^R~ Run Top2",
                                                               () => Application.Run (Top2 ())
                                                              ),
                                               new StatusItem (
                                                               Application.QuitKey,
                                                               $"{Application.QuitKey} to Quit",
                                                               () => Application.RequestStop ()
                                                              )
                                           }
                                          );
            top.Add (statusBar);

            var t1 = new Toplevel ();
            top.Add (t1);

            return top;
        }

        Toplevel Top2 ()
        {
            var top = new Toplevel (Application.Top.Frame);
            top.Text = "Top2";
            var win = new Window { Width = Dim.Fill (), Height = Dim.Fill () };

            var menu = new MenuBar (
                                    new MenuBarItem []
                                    {
                                        new MenuBarItem (
                                                         "_Stage",
                                                         new MenuItem []
                                                         {
                                                             new MenuItem (
                                                                           "_Close",
                                                                           "",
                                                                           () => Application
                                                                               .RequestStop (),
                                                                           null,
                                                                           null,
                                                                           Key.CtrlMask | Key.C
                                                                          )
                                                         }
                                                        )
                                    }
                                   );
            top.Add (menu);

            var statusBar = new StatusBar (
                                           new []
                                           {
                                               new StatusItem (
                                                               Key.CtrlMask | Key.C,
                                                               "~^C~ Close",
                                                               () => Application.RequestStop ()
                                                              ),
                                           }
                                          );
            top.Add (statusBar);

            win.Add (
                     new ListView { X = 0, Y = 0, Width = Dim.Fill (), Height = Dim.Fill () }
                    );
            top.Add (win);

            return top;
        }
    }
#endif
    [Fact]
    [AutoInitShutdown]
    public void Internal_Tests ()
    {
        var top = new Toplevel ();

        var eventInvoked = "";

        top.ChildUnloaded += (s, e) => eventInvoked = "ChildUnloaded";
        top.OnChildUnloaded (top);
        Assert.Equal ("ChildUnloaded", eventInvoked);
        top.ChildLoaded += (s, e) => eventInvoked = "ChildLoaded";
        top.OnChildLoaded (top);
        Assert.Equal ("ChildLoaded", eventInvoked);
        top.Closed += (s, e) => eventInvoked = "Closed";
        top.OnClosed (top);
        Assert.Equal ("Closed", eventInvoked);
        top.Closing += (s, e) => eventInvoked = "Closing";
        top.OnClosing (new ToplevelClosingEventArgs (top));
        Assert.Equal ("Closing", eventInvoked);
        top.AllChildClosed += (s, e) => eventInvoked = "AllChildClosed";
        top.OnAllChildClosed ();
        Assert.Equal ("AllChildClosed", eventInvoked);
        top.ChildClosed += (s, e) => eventInvoked = "ChildClosed";
        top.OnChildClosed (top);
        Assert.Equal ("ChildClosed", eventInvoked);
        top.Deactivate += (s, e) => eventInvoked = "Deactivate";
        top.OnDeactivate (top);
        Assert.Equal ("Deactivate", eventInvoked);
        top.Activate += (s, e) => eventInvoked = "Activate";
        top.OnActivate (top);
        Assert.Equal ("Activate", eventInvoked);
        top.Loaded += (s, e) => eventInvoked = "Loaded";
        top.OnLoaded ();
        Assert.Equal ("Loaded", eventInvoked);
        top.Ready += (s, e) => eventInvoked = "Ready";
        top.OnReady ();
        Assert.Equal ("Ready", eventInvoked);
        top.Unloaded += (s, e) => eventInvoked = "Unloaded";
        top.OnUnloaded ();
        Assert.Equal ("Unloaded", eventInvoked);

        top.AddMenuStatusBar (new MenuBar ());
        Assert.NotNull (top.MenuBar);
        top.AddMenuStatusBar (new StatusBar ());
        Assert.NotNull (top.StatusBar);
        top.RemoveMenuStatusBar (top.MenuBar);
        Assert.Null (top.MenuBar);
        top.RemoveMenuStatusBar (top.StatusBar);
        Assert.Null (top.StatusBar);

        Application.Begin (top);
        Assert.Equal (top, Application.Top);

        // Application.Top without menu and status bar.
        View supView = View.GetLocationEnsuringFullVisibility (top, 2, 2, out int nx, out int ny, out StatusBar sb);
        Assert.Equal (Application.Top, supView);
        Assert.Equal (0, nx);
        Assert.Equal (0, ny);
        Assert.Null (sb);

        top.AddMenuStatusBar (new MenuBar ());
        Assert.NotNull (top.MenuBar);

        // Application.Top with a menu and without status bar.
        View.GetLocationEnsuringFullVisibility (top, 2, 2, out nx, out ny, out sb);
        Assert.Equal (0, nx);
        Assert.Equal (1, ny);
        Assert.Null (sb);

        top.AddMenuStatusBar (new StatusBar ());
        Assert.NotNull (top.StatusBar);

        // Application.Top with a menu and status bar.
        View.GetLocationEnsuringFullVisibility (top, 2, 2, out nx, out ny, out sb);
        Assert.Equal (0, nx);

        // The available height is lower than the Application.Top height minus
        // the menu bar and status bar, then the top can go beyond the bottom
        Assert.Equal (2, ny);
        Assert.NotNull (sb);

        top.RemoveMenuStatusBar (top.MenuBar);
        Assert.Null (top.MenuBar);

        // Application.Top without a menu and with a status bar.
        View.GetLocationEnsuringFullVisibility (top, 2, 2, out nx, out ny, out sb);
        Assert.Equal (0, nx);

        // The available height is lower than the Application.Top height minus
        // the status bar, then the top can go beyond the bottom
        Assert.Equal (2, ny);
        Assert.NotNull (sb);

        top.RemoveMenuStatusBar (top.StatusBar);
        Assert.Null (top.StatusBar);
        Assert.Null (top.MenuBar);

        var win = new Window { Width = Dim.Fill (), Height = Dim.Fill () };
        top.Add (win);
        top.LayoutSubviews ();

        // The SuperView is always the same regardless of the caller.
        supView = View.GetLocationEnsuringFullVisibility (win, 0, 0, out nx, out ny, out sb);
        Assert.Equal (Application.Top, supView);
        supView = View.GetLocationEnsuringFullVisibility (win, 0, 0, out nx, out ny, out sb);
        Assert.Equal (Application.Top, supView);

        // Application.Top without menu and status bar.
        View.GetLocationEnsuringFullVisibility (win, 0, 0, out nx, out ny, out sb);
        Assert.Equal (0, nx);
        Assert.Equal (0, ny);
        Assert.Null (sb);

        top.AddMenuStatusBar (new MenuBar ());
        Assert.NotNull (top.MenuBar);

        // Application.Top with a menu and without status bar.
        View.GetLocationEnsuringFullVisibility (win, 2, 2, out nx, out ny, out sb);
        Assert.Equal (0, nx);
        Assert.Equal (1, ny);
        Assert.Null (sb);

        top.AddMenuStatusBar (new StatusBar ());
        Assert.NotNull (top.StatusBar);

        // Application.Top with a menu and status bar.
        View.GetLocationEnsuringFullVisibility (win, 30, 20, out nx, out ny, out sb);
        Assert.Equal (0, nx);

        // The available height is lower than the Application.Top height minus
        // the menu bar and status bar, then the top can go beyond the bottom
        Assert.Equal (20, ny);
        Assert.NotNull (sb);

        top.RemoveMenuStatusBar (top.MenuBar);
        top.RemoveMenuStatusBar (top.StatusBar);
        Assert.Null (top.StatusBar);
        Assert.Null (top.MenuBar);

        top.Remove (win);

        win = new Window { Width = 60, Height = 15 };
        top.Add (win);

        // Application.Top without menu and status bar.
        View.GetLocationEnsuringFullVisibility (win, 0, 0, out nx, out ny, out sb);
        Assert.Equal (0, nx);
        Assert.Equal (0, ny);
        Assert.Null (sb);

        top.AddMenuStatusBar (new MenuBar ());
        Assert.NotNull (top.MenuBar);

        // Application.Top with a menu and without status bar.
        View.GetLocationEnsuringFullVisibility (win, 2, 2, out nx, out ny, out sb);
        Assert.Equal (2, nx);
        Assert.Equal (2, ny);
        Assert.Null (sb);

        top.AddMenuStatusBar (new StatusBar ());
        Assert.NotNull (top.StatusBar);

        // Application.Top with a menu and status bar.
        View.GetLocationEnsuringFullVisibility (win, 30, 20, out nx, out ny, out sb);
        Assert.Equal (20, nx); // 20+60=80
        Assert.Equal (9, ny); // 9+15+1(mb)=25
        Assert.NotNull (sb);

        top.PositionToplevels ();
        Assert.Equal (new Rectangle (0, 1, 60, 15), win.Frame);

        //Assert.Null (Toplevel._dragPosition);
        win.NewMouseEvent (new MouseEvent { X = 6, Y = 0, Flags = MouseFlags.Button1Pressed });
        // Assert.Equal (new Point (6, 0), Toplevel._dragPosition);
        win.NewMouseEvent (new MouseEvent { X = 6, Y = 0, Flags = MouseFlags.Button1Released });
        //Assert.Null (Toplevel._dragPosition);
        win.CanFocus = false;
        win.NewMouseEvent (new MouseEvent { X = 6, Y = 0, Flags = MouseFlags.Button1Pressed });
        //Assert.Null (Toplevel._dragPosition);
    }

    [Fact]
    [AutoInitShutdown]
    public void KeyBindings_Command ()
    {
        var isRunning = false;

        var win1 = new Window { Id = "win1", Width = Dim.Percent (50f), Height = Dim.Fill () };
        var lblTf1W1 = new Label { Id = "lblTf1W1", Text = "Enter text in TextField on Win1:" };

        var tf1W1 = new TextField
        {
            Id = "tf1W1", X = Pos.Right (lblTf1W1) + 1, Width = Dim.Fill (), Text = "Text1 on Win1"
        };

        var lblTvW1 = new Label
        {
            Id = "lblTvW1", Y = Pos.Bottom (lblTf1W1) + 1, Text = "Enter text in TextView on Win1:"
        };

        var tvW1 = new TextView
        {
            Id = "tvW1",
            X = Pos.Left (tf1W1),
            Width = Dim.Fill (),
            Height = 2,
            Text = "First line Win1\nSecond line Win1"
        };

        var lblTf2W1 = new Label
        {
            Id = "lblTf2W1", Y = Pos.Bottom (lblTvW1) + 1, Text = "Enter text in TextField on Win1:"
        };
        var tf2W1 = new TextField { Id = "tf2W1", X = Pos.Left (tf1W1), Width = Dim.Fill (), Text = "Text2 on Win1" };
        win1.Add (lblTf1W1, tf1W1, lblTvW1, tvW1, lblTf2W1, tf2W1);

        var win2 = new Window
        {
            Id = "win2", X = Pos.Right (win1) + 1, Width = Dim.Percent (50f), Height = Dim.Fill ()
        };
        var lblTf1W2 = new Label { Id = "lblTf1W2", Text = "Enter text in TextField on Win2:" };

        var tf1W2 = new TextField
        {
            Id = "tf1W2", X = Pos.Right (lblTf1W2) + 1, Width = Dim.Fill (), Text = "Text1 on Win2"
        };

        var lblTvW2 = new Label
        {
            Id = "lblTvW2", Y = Pos.Bottom (lblTf1W2) + 1, Text = "Enter text in TextView on Win2:"
        };

        var tvW2 = new TextView
        {
            Id = "tvW2",
            X = Pos.Left (tf1W2),
            Width = Dim.Fill (),
            Height = 2,
            Text = "First line Win1\nSecond line Win2"
        };

        var lblTf2W2 = new Label
        {
            Id = "lblTf2W2", Y = Pos.Bottom (lblTvW2) + 1, Text = "Enter text in TextField on Win2:"
        };
        var tf2W2 = new TextField { Id = "tf2W2", X = Pos.Left (tf1W2), Width = Dim.Fill (), Text = "Text2 on Win2" };
        win2.Add (lblTf1W2, tf1W2, lblTvW2, tvW2, lblTf2W2, tf2W2);

        Toplevel top = new ();
        top.Add (win1, win2);
        top.Loaded += (s, e) => isRunning = true;
        top.Closing += (s, e) => isRunning = false;
        Application.Begin (top);
        top.Running = true;

        Assert.Equal (new Rectangle (0, 0, 40, 25), win1.Frame);
        Assert.Equal (new Rectangle (41, 0, 40, 25), win2.Frame);
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf1W1, top.MostFocused);

        Assert.True (isRunning);
        Assert.True (Application.OnKeyDown (Application.QuitKey));
        Assert.False (isRunning);
        Assert.True (Application.OnKeyDown (Key.Z.WithCtrl));

        Assert.True (Application.OnKeyDown (Key.F5)); // refresh

        Assert.True (Application.OnKeyDown (Key.Tab));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tvW1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.Tab));
        Assert.Equal ($"\tFirst line Win1{Environment.NewLine}Second line Win1", tvW1.Text);
        Assert.True (Application.OnKeyDown (Key.Tab.WithShift));
        Assert.Equal ($"First line Win1{Environment.NewLine}Second line Win1", tvW1.Text);
        Assert.True (Application.OnKeyDown (Key.Tab.WithCtrl));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf2W1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.Tab));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf1W1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.CursorRight));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf1W1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.CursorDown));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tvW1, top.MostFocused);
#if UNIX_KEY_BINDINGS
        Assert.True (Application.OnKeyDown (new (Key.I.WithCtrl)));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf2W1, top.MostFocused);
#endif
        Assert.True (Application.OnKeyDown (Key.Tab.WithShift));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tvW1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.CursorLeft));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf1W1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.CursorUp));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf2W1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.Tab.WithCtrl));
        Assert.Equal (win2, top.Focused);
        Assert.Equal (tf1W2, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.Tab.WithCtrl.WithShift));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf2W1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Application.AlternateForwardKey));
        Assert.Equal (win2, top.Focused);
        Assert.Equal (tf1W2, top.MostFocused);
        Assert.True (Application.OnKeyDown (Application.AlternateBackwardKey));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf2W1, top.MostFocused);
        Assert.True (Application.OnKeyDown (Key.CursorUp));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tvW1, top.MostFocused);
#if UNIX_KEY_BINDINGS
        Assert.True (Application.OnKeyDown (new (Key.B.WithCtrl)));
#else
        Assert.True (Application.OnKeyDown (Key.CursorLeft));
#endif
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf1W1, top.MostFocused);

        Assert.True (Application.OnKeyDown (Key.CursorDown));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tvW1, top.MostFocused);
        Assert.Equal (Point.Empty, tvW1.CursorPosition);
        Assert.True (Application.OnKeyDown (Key.End.WithCtrl));
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tvW1, top.MostFocused);
        Assert.Equal (new Point (16, 1), tvW1.CursorPosition);
#if UNIX_KEY_BINDINGS
        Assert.True (Application.OnKeyDown (new (Key.F.WithCtrl)));
#else
        Assert.True (Application.OnKeyDown (Key.CursorRight));
#endif
        Assert.Equal (win1, top.Focused);
        Assert.Equal (tf2W1, top.MostFocused);

#if UNIX_KEY_BINDINGS
        Assert.True (Application.OnKeyDown (new (Key.L.WithCtrl)));
#else
        Assert.True (Application.OnKeyDown (Key.F5));
#endif
    }

    [Fact]
    [AutoInitShutdown]
    public void KeyBindings_Command_With_OverlappedTop ()
    {
        Toplevel top = new ();
        Assert.Null (Application.OverlappedTop);
        top.IsOverlappedContainer = true;
        Application.Begin (top);
        Assert.Equal (Application.Top, Application.OverlappedTop);

        var isRunning = true;

        var win1 = new Window { Id = "win1", Width = Dim.Percent (50f), Height = Dim.Fill () };
        var lblTf1W1 = new Label { Text = "Enter text in TextField on Win1:" };
        var tf1W1 = new TextField { X = Pos.Right (lblTf1W1) + 1, Width = Dim.Fill (), Text = "Text1 on Win1" };
        var lblTvW1 = new Label { Y = Pos.Bottom (lblTf1W1) + 1, Text = "Enter text in TextView on Win1:" };

        var tvW1 = new TextView
        {
            X = Pos.Left (tf1W1), Width = Dim.Fill (), Height = 2, Text = "First line Win1\nSecond line Win1"
        };
        var lblTf2W1 = new Label { Y = Pos.Bottom (lblTvW1) + 1, Text = "Enter text in TextField on Win1:" };
        var tf2W1 = new TextField { X = Pos.Left (tf1W1), Width = Dim.Fill (), Text = "Text2 on Win1" };
        win1.Add (lblTf1W1, tf1W1, lblTvW1, tvW1, lblTf2W1, tf2W1);

        var win2 = new Window { Id = "win2", Width = Dim.Percent (50f), Height = Dim.Fill () };
        var lblTf1W2 = new Label { Text = "Enter text in TextField on Win2:" };
        var tf1W2 = new TextField { X = Pos.Right (lblTf1W2) + 1, Width = Dim.Fill (), Text = "Text1 on Win2" };
        var lblTvW2 = new Label { Y = Pos.Bottom (lblTf1W2) + 1, Text = "Enter text in TextView on Win2:" };

        var tvW2 = new TextView
        {
            X = Pos.Left (tf1W2), Width = Dim.Fill (), Height = 2, Text = "First line Win1\nSecond line Win2"
        };
        var lblTf2W2 = new Label { Y = Pos.Bottom (lblTvW2) + 1, Text = "Enter text in TextField on Win2:" };
        var tf2W2 = new TextField { X = Pos.Left (tf1W2), Width = Dim.Fill (), Text = "Text2 on Win2" };
        win2.Add (lblTf1W2, tf1W2, lblTvW2, tvW2, lblTf2W2, tf2W2);

        win1.Closing += (s, e) => isRunning = false;
        Assert.Null (top.Focused);
        Assert.Equal (top, Application.Current);
        Assert.True (top.IsCurrentTop);
        Assert.Equal (top, Application.OverlappedTop);
        Application.Begin (win1);
        Assert.Equal (new Rectangle (0, 0, 40, 25), win1.Frame);
        Assert.NotEqual (top, Application.Current);
        Assert.False (top.IsCurrentTop);
        Assert.Equal (win1, Application.Current);
        Assert.True (win1.IsCurrentTop);
        Assert.True (win1.IsOverlapped);
        Assert.Null (top.Focused);
        Assert.Null (top.MostFocused);
        Assert.Equal (tf1W1, win1.MostFocused);
        Assert.True (win1.IsOverlapped);
        Assert.Single (Application.OverlappedChildren);
        Application.Begin (win2);
        Assert.Equal (new Rectangle (0, 0, 40, 25), win2.Frame);
        Assert.NotEqual (top, Application.Current);
        Assert.False (top.IsCurrentTop);
        Assert.Equal (win2, Application.Current);
        Assert.True (win2.IsCurrentTop);
        Assert.True (win2.IsOverlapped);
        Assert.Null (top.Focused);
        Assert.Null (top.MostFocused);
        Assert.Equal (tf1W2, win2.MostFocused);
        Assert.Equal (2, Application.OverlappedChildren.Count);

        Application.MoveToOverlappedChild (win1);
        Assert.Equal (win1, Application.Current);
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        win1.Running = true;
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Application.QuitKey));
        Assert.False (isRunning);
        Assert.False (win1.Running);
        Assert.Equal (win1, Application.OverlappedChildren [0]);

        Assert.True (
                     Application.OverlappedChildren [0].NewKeyDownEvent (Key.Z.WithCtrl)
                    );

        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.F5)); // refresh

        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.Tab));
        Assert.True (win1.IsCurrentTop);
        Assert.Equal (tvW1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.Tab));
        Assert.Equal ($"\tFirst line Win1{Environment.NewLine}Second line Win1", tvW1.Text);

        Assert.True (
                     Application.OverlappedChildren [0]
                                .NewKeyDownEvent (Key.Tab.WithShift)
                    );
        Assert.Equal ($"First line Win1{Environment.NewLine}Second line Win1", tvW1.Text);

        Assert.True (
                     Application.OverlappedChildren [0]
                                .NewKeyDownEvent (Key.Tab.WithCtrl)
                    );
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf2W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.Tab));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorRight));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorDown));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tvW1, win1.MostFocused);
#if UNIX_KEY_BINDINGS
        Assert.True (Application.OverlappedChildren [0].ProcessKeyDown (new (Key.I.WithCtrl)));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf2W1, win1.MostFocused);
#endif
        Assert.True (
                     Application.OverlappedChildren [0]
                                .NewKeyDownEvent (Key.Tab.WithShift)
                    );
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tvW1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorLeft));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorUp));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf2W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.Tab));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W1, win1.MostFocused);

        Assert.True (
                     Application.OverlappedChildren [0]
                                .NewKeyDownEvent (Key.Tab.WithCtrl)
                    );
        Assert.Equal (win2, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W2, win2.MostFocused);
        tf2W2.SetFocus ();
        Assert.True (tf2W2.HasFocus);

        Assert.True (
                     Application.OverlappedChildren [0]
                                .NewKeyDownEvent (Key.Tab.WithCtrl.WithShift)
                    );
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Application.AlternateForwardKey));
        Assert.Equal (win2, Application.OverlappedChildren [0]);
        Assert.Equal (tf2W2, win2.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Application.AlternateBackwardKey));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorDown));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tvW1, win1.MostFocused);
#if UNIX_KEY_BINDINGS
        Assert.True (Application.OverlappedChildren [0].ProcessKeyDown (new (Key.B.WithCtrl)));
#else
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorLeft));
#endif
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf1W1, win1.MostFocused);
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorDown));
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tvW1, win1.MostFocused);
        Assert.Equal (Point.Empty, tvW1.CursorPosition);

        Assert.True (
                     Application.OverlappedChildren [0]
                                .NewKeyDownEvent (Key.End.WithCtrl)
                    );
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tvW1, win1.MostFocused);
        Assert.Equal (new Point (16, 1), tvW1.CursorPosition);
#if UNIX_KEY_BINDINGS
        Assert.True (Application.OverlappedChildren [0].ProcessKeyDown (new (Key.F.WithCtrl)));
#else
        Assert.True (Application.OverlappedChildren [0].NewKeyDownEvent (Key.CursorRight));
#endif
        Assert.Equal (win1, Application.OverlappedChildren [0]);
        Assert.Equal (tf2W1, win1.MostFocused);

#if UNIX_KEY_BINDINGS
        Assert.True (Application.OverlappedChildren [0].ProcessKeyDown (new (Key.L.WithCtrl)));
#endif
        win2.Dispose ();
        win1.Dispose ();
    }

    [Fact]
    public void Added_Event_Should_Not_Be_Used_To_Initialize_Toplevel_Events ()
    {
        Key alternateForwardKey = default;
        Key alternateBackwardKey = default;
        Key quitKey = default;
        var wasAdded = false;

        var view = new View ();
        view.Added += View_Added;

        void View_Added (object sender, SuperViewChangedEventArgs e)
        {
            Assert.Throws<NullReferenceException> (
                                                   () =>
                                                       Application.Top.AlternateForwardKeyChanged +=
                                                           (s, e) => alternateForwardKey = (KeyCode)e.OldKey
                                                  );

            Assert.Throws<NullReferenceException> (
                                                   () =>
                                                       Application.Top.AlternateBackwardKeyChanged +=
                                                           (s, e) => alternateBackwardKey = (KeyCode)e.OldKey
                                                  );

            Assert.Throws<NullReferenceException> (
                                                   () =>
                                                       Application.Top.QuitKeyChanged += (s, e) =>
                                                                                             quitKey = (KeyCode)e.OldKey
                                                  );
            Assert.False (wasAdded);
            wasAdded = true;
            view.Added -= View_Added;
        }

        var win = new Window ();
        win.Add (view);
        Application.Init (new FakeDriver ());
        Toplevel top = new ();
        top.Add (win);

        Assert.True (wasAdded);

        Application.Shutdown ();
    }

    [Fact]
    [AutoInitShutdown]
    public void AlternateForwardKeyChanged_AlternateBackwardKeyChanged_QuitKeyChanged_Events ()
    {
        Key alternateForwardKey = KeyCode.Null;
        Key alternateBackwardKey = KeyCode.Null;
        Key quitKey = KeyCode.Null;

        Toplevel top = new ();
        var view = new View ();
        view.Initialized += View_Initialized;

        void View_Initialized (object sender, EventArgs e)
        {
            top.AlternateForwardKeyChanged += (s, e) => alternateForwardKey = e.OldKey;
            top.AlternateBackwardKeyChanged += (s, e) => alternateBackwardKey = e.OldKey;
            top.QuitKeyChanged += (s, e) => quitKey = e.OldKey;
        }

        var win = new Window ();
        win.Add (view);
        top.Add (win);
        Application.Begin (top);

        Assert.Equal (KeyCode.Null, alternateForwardKey);
        Assert.Equal (KeyCode.Null, alternateBackwardKey);
        Assert.Equal (KeyCode.Null, quitKey);

        Assert.Equal (KeyCode.PageDown | KeyCode.CtrlMask, Application.AlternateForwardKey);
        Assert.Equal (KeyCode.PageUp | KeyCode.CtrlMask, Application.AlternateBackwardKey);
        Assert.Equal (KeyCode.Q | KeyCode.CtrlMask, Application.QuitKey);

        Application.AlternateForwardKey = KeyCode.A;
        Application.AlternateBackwardKey = KeyCode.B;
        Application.QuitKey = KeyCode.C;

        Assert.Equal (KeyCode.PageDown | KeyCode.CtrlMask, alternateForwardKey);
        Assert.Equal (KeyCode.PageUp | KeyCode.CtrlMask, alternateBackwardKey);
        Assert.Equal (KeyCode.Q | KeyCode.CtrlMask, quitKey);

        Assert.Equal (KeyCode.A, Application.AlternateForwardKey);
        Assert.Equal (KeyCode.B, Application.AlternateBackwardKey);
        Assert.Equal (KeyCode.C, Application.QuitKey);

        // Replacing the defaults keys to avoid errors on others unit tests that are using it.
        Application.AlternateForwardKey = Key.PageDown.WithCtrl;
        Application.AlternateBackwardKey = Key.PageUp.WithCtrl;
        Application.QuitKey = Key.Q.WithCtrl;

        Assert.Equal (KeyCode.PageDown | KeyCode.CtrlMask, Application.AlternateForwardKey);
        Assert.Equal (KeyCode.PageUp | KeyCode.CtrlMask, Application.AlternateBackwardKey);
        Assert.Equal (KeyCode.Q | KeyCode.CtrlMask, Application.QuitKey);
    }

    [Fact]
    [AutoInitShutdown]
    public void Mouse_Drag_On_Top_With_Superview_Null ()
    {
        var win = new Window ();
        Toplevel top = new ();
        top.Add (win);
        int iterations = -1;
        Window testWindow;

        Application.Iteration += (s, a) =>
                                 {
                                     iterations++;

                                     if (iterations == 0)
                                     {
                                         ((FakeDriver)Application.Driver).SetBufferSize (15, 7);

                                         // Don't use MessageBox here; it's too complicated for this unit test; just use Window
                                         testWindow = new Window
                                         {
                                             Text = "Hello",
                                             X = 2,
                                             Y = 2,
                                             Width = 10,
                                             Height = 3
                                         };
                                         Application.Run (testWindow);
                                     }
                                     else if (iterations == 1)
                                     {
                                         Assert.Equal(new Point(2,2), Application.Current.Frame.Location);
                                     }
                                     else if (iterations == 2)
                                     {
                                         Assert.Null (Application.MouseGrabView);

                                         // Grab the mouse
                                         Application.OnMouseEvent (new () { X = 3, Y = 2, Flags = MouseFlags.Button1Pressed });

                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);
                                         Assert.Equal (new Rectangle (2, 2, 10, 3), Application.Current.Frame);
                                     }
                                     else if (iterations == 3)
                                     {
                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);

                                         // Drag to left
                                         Application.OnMouseEvent (new ()
                                         {
                                             X = 2,
                                             Y = 2,
                                             Flags = MouseFlags.Button1Pressed
                                                     | MouseFlags.ReportMousePosition
                                         });
                                         Application.Refresh ();

                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);
                                         Assert.Equal (new Rectangle (1, 2, 10, 3), Application.Current.Frame);
                                     }
                                     else if (iterations == 4)
                                     {
                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);
                                         Assert.Equal (new Point (1, 2), Application.Current.Frame.Location);

                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);
                                     }
                                     else if (iterations == 5)
                                     {
                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);

                                         // Drag up
                                         Application.OnMouseEvent (new ()
                                         {
                                             X = 2,
                                             Y = 1,
                                             Flags = MouseFlags.Button1Pressed
                                                     | MouseFlags.ReportMousePosition
                                         });
                                         Application.Refresh ();

                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);
                                         Assert.Equal (new Rectangle (1, 1, 10, 3), Application.Current.Frame);
                                     }
                                     else if (iterations == 6)
                                     {
                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);
                                         Assert.Equal (new Point (1, 1), Application.Current.Frame.Location);


                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);
                                         Assert.Equal (new Rectangle (1, 1, 10, 3), Application.Current.Frame);
                                     }
                                     else if (iterations == 7)
                                     {
                                         Assert.Equal (Application.Current.Border, Application.MouseGrabView);

                                         // Ungrab the mouse
                                         Application.OnMouseEvent (new () { X = 2, Y = 1, Flags = MouseFlags.Button1Released });
                                         Application.Refresh ();

                                         Assert.Null (Application.MouseGrabView);
                                     }
                                     else if (iterations == 8)
                                     {
                                         Application.RequestStop ();
                                     }
                                     else if (iterations == 9)
                                     {
                                         Application.RequestStop ();
                                     }
                                 };

        Application.Run (top);
    }

    [Fact]
    [AutoInitShutdown]
    public void Mouse_Drag_On_Top_With_Superview_Not_Null ()
    {
        var win = new Window { X = 3, Y = 2, Width = 10, Height = 5 };
        Toplevel top = new ();
        top.Add (win);

        int iterations = -1;

        var movex = 0;
        var movey = 0;

        var location = new Rectangle (win.Frame.X, win.Frame.Y, 7, 3);

        Application.Iteration += (s, a) =>
                                 {
                                     iterations++;

                                     if (iterations == 0)
                                     {
                                         ((FakeDriver)Application.Driver).SetBufferSize (30, 10);
                                     }
                                     else if (iterations == 1)
                                     {
                                         location = win.Frame;

                                         Assert.Null (Application.MouseGrabView);

                                         // Grab the mouse
                                         Application.OnMouseEvent (new MouseEvent
                                         {
                                             X = win.Frame.X, Y = win.Frame.Y,
                                             Flags = MouseFlags.Button1Pressed
                                         });

                                         Assert.Equal (win.Border, Application.MouseGrabView);
                                     }
                                     else if (iterations == 2)
                                     {
                                         Assert.Equal (win.Border, Application.MouseGrabView);

                                         // Drag to left
                                         movex = 1;
                                         movey = 0;

                                         Application.OnMouseEvent (new MouseEvent
                                         {
                                             X = win.Frame.X + movex,
                                             Y = win.Frame.Y + movey,
                                             Flags = MouseFlags.Button1Pressed
                                                     | MouseFlags.ReportMousePosition
                                         });

                                         Assert.Equal (win.Border, Application.MouseGrabView);
                                     }
                                     else if (iterations == 3)
                                     {
                                         // we should have moved +1, +0
                                         Assert.Equal (win.Border, Application.MouseGrabView);
                                         Assert.Equal (win.Border, Application.MouseGrabView);
                                         location.Offset (movex, movey);
                                     }
                                     else if (iterations == 4)
                                     {
                                         Assert.Equal (win.Border, Application.MouseGrabView);

                                         // Drag up
                                         movex = 0;
                                         movey = -1;

                                         Application.OnMouseEvent (new MouseEvent
                                         {
                                             X = win.Frame.X + movex,
                                             Y = win.Frame.Y + movey,
                                             Flags = MouseFlags.Button1Pressed
                                                     | MouseFlags.ReportMousePosition
                                         });

                                         Assert.Equal (win.Border, Application.MouseGrabView);
                                     }
                                     else if (iterations == 5)
                                     {
                                         // we should have moved +0, -1
                                         Assert.Equal (win.Border, Application.MouseGrabView);
                                         location.Offset (movex, movey);
                                         Assert.Equal (location, win.Frame);
                                     }
                                     else if (iterations == 6)
                                     {
                                         Assert.Equal (win.Border, Application.MouseGrabView);

                                         // Ungrab the mouse
                                         movex = 0;
                                         movey = 0;

                                         Application.OnMouseEvent (new MouseEvent
                                         {
                                             X = win.Frame.X + movex, Y = win.Frame.Y + movey,
                                             Flags = MouseFlags.Button1Released
                                         });

                                         Assert.Null (Application.MouseGrabView);
                                     }
                                     else if (iterations == 7)
                                     {
                                         Application.RequestStop ();
                                     }
                                 };

        Application.Run (top);
    }

    [Fact]
    [AutoInitShutdown]
    public void GetLocationThatFits_With_Border_Null_Not_Throws ()
    {
        var top = new Toplevel ();
        Application.Begin (top);

        Exception exception = Record.Exception (() => ((FakeDriver)Application.Driver).SetBufferSize (0, 10));
        Assert.Null (exception);

        exception = Record.Exception (() => ((FakeDriver)Application.Driver).SetBufferSize (10, 0));
        Assert.Null (exception);
    }

    [Fact]
    [AutoInitShutdown]
    public void OnEnter_OnLeave_Triggered_On_Application_Begin_End ()
    {
        var isEnter = false;
        var isLeave = false;
        var v = new View ();
        v.Enter += (s, _) => isEnter = true;
        v.Leave += (s, _) => isLeave = true;
        Toplevel top = new ();
        top.Add (v);

        Assert.False (v.CanFocus);
        Exception exception = Record.Exception (() => top.OnEnter (top));
        Assert.Null (exception);
        exception = Record.Exception (() => top.OnLeave (top));
        Assert.Null (exception);

        v.CanFocus = true;
        RunState rsTop = Application.Begin (top);

        // From the v view
        Assert.True (isEnter);
        // The Leave event is only raised on the End method
        // and the top is still running
        Assert.False (isLeave);

        isEnter = false;
        var d = new Dialog ();
        var dv = new View { CanFocus = true };
        dv.Enter += (s, _) => isEnter = true;
        dv.Leave += (s, _) => isLeave = true;
        d.Add (dv);
        RunState rsDialog = Application.Begin (d);

        // From the dv view
        Assert.True (isEnter);
        Assert.False (isLeave);
        Assert.True (dv.HasFocus);

        isEnter = false;

        Application.End (rsDialog);

        // From the v view
        Assert.True (isEnter);
        // From the dv view
        Assert.True (isLeave);
        Assert.True (v.HasFocus);

        Application.End (rsTop);
    }

    [Fact]
    [AutoInitShutdown]
    public void OnEnter_OnLeave_Triggered_On_Application_Begin_End_With_More_Toplevels ()
    {
        var iterations = 0;
        var steps = new int [4];
        var isEnterTop = false;
        var isLeaveTop = false;
        var vt = new View ();
        Toplevel top = new ();
        var diag = new Dialog ();

        vt.Enter += (s, e) =>
                    {
                        iterations++;
                        isEnterTop = true;

                        if (iterations == 1)
                        {
                            steps [0] = iterations;
                            Assert.Null (e.View);
                        }
                        else
                        {
                            steps [3] = iterations;
                            Assert.Equal (diag, e.View);
                        }
                    };

        vt.Leave += (s, e) =>
                    {
                        // This will never be raised
                        iterations++;
                        isLeaveTop = true;
                        Assert.Equal (diag, e.View);
                    };
        top.Add (vt);

        Assert.False (vt.CanFocus);
        Exception exception = Record.Exception (() => top.OnEnter (top));
        Assert.Null (exception);
        exception = Record.Exception (() => top.OnLeave (top));
        Assert.Null (exception);

        vt.CanFocus = true;
        RunState rsTop = Application.Begin (top);

        Assert.True (isEnterTop);
        Assert.False (isLeaveTop);

        isEnterTop = false;
        var isEnterDiag = false;
        var isLeaveDiag = false;
        var vd = new View ();

        vd.Enter += (s, e) =>
                    {
                        iterations++;
                        steps [1] = iterations;
                        isEnterDiag = true;
                        Assert.Null (e.View);
                    };

        vd.Leave += (s, e) =>
                    {
                        iterations++;
                        steps [2] = iterations;
                        isLeaveDiag = true;
                        Assert.Equal (top, e.View);
                    };
        diag.Add (vd);

        Assert.False (vd.CanFocus);
        exception = Record.Exception (() => diag.OnEnter (diag));
        Assert.Null (exception);
        exception = Record.Exception (() => diag.OnLeave (diag));
        Assert.Null (exception);

        vd.CanFocus = true;
        RunState rsDiag = Application.Begin (diag);

        Assert.True (isEnterDiag);
        Assert.False (isLeaveDiag);
        Assert.False (isEnterTop);
        // The Leave event is only raised on the End method
        // and the top is still running
        Assert.False (isLeaveTop);

        isEnterDiag = false;
        isLeaveTop = false;
        Application.End (rsDiag);

        Assert.False (isEnterDiag);
        Assert.True (isLeaveDiag);
        Assert.True (isEnterTop);
        // Leave event on top cannot be raised
        // because Current is null on the End method
        Assert.False (isLeaveTop);
        Assert.True (vt.HasFocus);

        Application.End (rsTop);

        Assert.Equal (1, steps [0]);
        Assert.Equal (2, steps [1]);
        Assert.Equal (3, steps [2]);
        Assert.Equal (4, steps [^1]);
    }

    [Fact]
    [AutoInitShutdown]
    public void PositionCursor_SetCursorVisibility_To_Invisible_If_Focused_Is_Null ()
    {
        var tf = new TextField { Width = 5, Text = "test" };
        var view = new View { Width = 10, Height = 10 };
        view.Add (tf);
        var top = new Toplevel ();
        top.Add (view);
        Application.Begin (top);

        Assert.True (tf.HasFocus);
        Application.Driver.GetCursorVisibility (out CursorVisibility cursor);
        Assert.Equal (CursorVisibility.Default, cursor);

        view.Enabled = false;
        Assert.False (tf.HasFocus);
        Application.Refresh ();
        Application.Driver.GetCursorVisibility (out cursor);
        Assert.Equal (CursorVisibility.Invisible, cursor);
    }

    [Fact]
    [AutoInitShutdown]
    public void IsLoaded_Application_Begin ()
    {
        Toplevel top = new ();
        Assert.False (top.IsLoaded);

        Application.Begin (top);
        Assert.True (top.IsLoaded);
    }

    [Fact]
    [AutoInitShutdown]
    public void IsLoaded_With_Sub_Toplevel_Application_Begin_NeedDisplay ()
    {
        Toplevel top = new ();
        var subTop = new Toplevel ();
        var view = new View { Frame = new Rectangle (0, 0, 20, 10) };
        subTop.Add (view);
        top.Add (subTop);

        Assert.False (top.IsLoaded);
        Assert.False (subTop.IsLoaded);
        Assert.Equal (new Rectangle (0, 0, 20, 10), view.Frame);

        view.LayoutStarted += view_LayoutStarted;

        void view_LayoutStarted (object sender, LayoutEventArgs e)
        {
            Assert.Equal (new Rectangle (0, 0, 20, 10), view._needsDisplayRect);
            view.LayoutStarted -= view_LayoutStarted;
        }

        Application.Begin (top);

        Assert.True (top.IsLoaded);
        Assert.True (subTop.IsLoaded);
        Assert.Equal (new Rectangle (0, 0, 20, 10), view.Frame);

        view.Frame = new (1, 3, 10, 5);
        Assert.Equal (new (1, 3, 10, 5), view.Frame);
        Assert.Equal (new (0, 0, 10, 5), view._needsDisplayRect);

        view.OnDrawContent (view.Viewport);
        view.Frame = new (1, 3, 10, 5);
        Assert.Equal (new (1, 3, 10, 5), view.Frame);
        Assert.Equal (new (0, 0, 10, 5), view._needsDisplayRect);
    }

    [Fact]
    [AutoInitShutdown]
    public void Toplevel_Inside_ScrollView_MouseGrabView ()
    {
        var scrollView = new ScrollView
        {
            X = 3,
            Y = 3,
            Width = 40,
            Height = 16,
            ContentSize = new (200, 100)
        };
        var win = new Window { X = 3, Y = 3, Width = Dim.Fill (3), Height = Dim.Fill (3) };
        scrollView.Add (win);
        Toplevel top = new ();
        top.Add (scrollView);
        Application.Begin (top);

        Assert.Equal (new (0, 0, 80, 25), top.Frame);
        Assert.Equal (new (3, 3, 40, 16), scrollView.Frame);
        Assert.Equal (new (0, 0, 200, 100), scrollView.Subviews [0].Frame);
        Assert.Equal (new (3, 3, 194, 94), win.Frame);


        Application.OnMouseEvent (new MouseEvent { X = 6, Y = 6, Flags = MouseFlags.Button1Pressed });
        Assert.Equal (win.Border, Application.MouseGrabView);
        Assert.Equal (new (3, 3, 194, 94), win.Frame);

        Application.OnMouseEvent (new MouseEvent { X = 9, Y = 9, Flags = MouseFlags.Button1Pressed | MouseFlags.ReportMousePosition });
        Assert.Equal (win.Border, Application.MouseGrabView);
        top.SetNeedsLayout ();
        top.LayoutSubviews ();
        Assert.Equal (new Rectangle (6, 6, 191, 91), win.Frame);
        Application.Refresh ();

        Application.OnMouseEvent (new MouseEvent
        {
            X = 5,
            Y = 5,
            Flags = MouseFlags.Button1Pressed
                    | MouseFlags.ReportMousePosition
        });
        Assert.Equal (win.Border, Application.MouseGrabView);
        top.SetNeedsLayout ();
        top.LayoutSubviews ();
        Assert.Equal (new Rectangle (2, 2, 195, 95), win.Frame);
        Application.Refresh ();

        Application.OnMouseEvent (new MouseEvent { X = 5, Y = 5, Flags = MouseFlags.Button1Released });
        // ScrollView always grab the mouse when the container's subview OnMouseEnter don't want grab the mouse
        Assert.Equal (scrollView, Application.MouseGrabView);

        Application.OnMouseEvent (new MouseEvent { X = 4, Y = 4, Flags = MouseFlags.ReportMousePosition });
        Assert.Equal (scrollView, Application.MouseGrabView);
    }

    [Fact]
    [AutoInitShutdown]
    public void Window_Viewport_Bigger_Than_Driver_Cols_And_Rows_Allow_Drag_Beyond_Left_Right_And_Bottom ()
    {
        Toplevel top = new ();
        var window = new Window { Width = 20, Height = 3 };
        RunState rsTop = Application.Begin (top);
        ((FakeDriver)Application.Driver).SetBufferSize (40, 10);
        RunState rsWindow = Application.Begin (window);
        Application.Refresh ();
        Assert.Equal (new Rectangle (0, 0, 40, 10), top.Frame);
        Assert.Equal (new Rectangle (0, 0, 20, 3), window.Frame);

        Assert.Null (Application.MouseGrabView);

        Application.OnMouseEvent (new MouseEvent { X = 0, Y = 0, Flags = MouseFlags.Button1Pressed });

        Assert.Equal (window.Border, Application.MouseGrabView);

        Application.OnMouseEvent (new MouseEvent
        {
            X = -11,
            Y = -4,
            Flags = MouseFlags.Button1Pressed
                    | MouseFlags.ReportMousePosition
        });

        Application.Refresh ();
        Assert.Equal (new Rectangle (0, 0, 40, 10), top.Frame);
        Assert.Equal (new Rectangle (0, 0, 20, 3), window.Frame);

        // Changes Top size to same size as Dialog more menu and scroll bar
        ((FakeDriver)Application.Driver).SetBufferSize (20, 3);

        Application.OnMouseEvent (new MouseEvent
        {
            X = -1,
            Y = -1,
            Flags = MouseFlags.Button1Pressed
                    | MouseFlags.ReportMousePosition
        });

        Application.Refresh ();
        Assert.Equal (new Rectangle (0, 0, 20, 3), top.Frame);
        Assert.Equal (new Rectangle (0, 0, 20, 3), window.Frame);

        // Changes Top size smaller than Dialog size
        ((FakeDriver)Application.Driver).SetBufferSize (19, 2);

        Application.OnMouseEvent (new MouseEvent
        {
            X = -1,
            Y = -1,
            Flags = MouseFlags.Button1Pressed
                    | MouseFlags.ReportMousePosition
        });

        Application.Refresh ();
        Assert.Equal (new Rectangle (0, 0, 19, 2), top.Frame);
        Assert.Equal (new Rectangle (-1, 0, 20, 3), window.Frame);

        Application.OnMouseEvent (new MouseEvent
        {
            X = 18,
            Y = 1,
            Flags = MouseFlags.Button1Pressed
                    | MouseFlags.ReportMousePosition
        });

        Application.Refresh ();
        Assert.Equal (new Rectangle (0, 0, 19, 2), top.Frame);
        Assert.Equal (new Rectangle (18, 1, 20, 3), window.Frame);

        // On a real app we can't go beyond the SuperView bounds
        Application.OnMouseEvent (new MouseEvent
        {
            X = 19,
            Y = 2,
            Flags = MouseFlags.Button1Pressed
                    | MouseFlags.ReportMousePosition
        });

        Application.Refresh ();
        Assert.Equal (new Rectangle (0, 0, 19, 2), top.Frame);
        Assert.Equal (new Rectangle (19, 2, 20, 3), window.Frame);
        TestHelpers.AssertDriverContentsWithFrameAre (@"", _output);

        Application.End (rsWindow);
        Application.End (rsTop);
    }

    [Fact]
    [AutoInitShutdown]
    public void Modal_As_Top_Will_Drag_Cleanly ()
    {
        // Don't use Dialog as a Top, use a Window instead - dialog has complex layout behavior that is not needed here.
        var window = new Window { Width = 10, Height = 3 };

        window.Add (
                    new Label
                    {
                        X = Pos.Center (),
                        Y = Pos.Center (),
                        AutoSize = false,
                        Width = Dim.Fill (),
                        Height = Dim.Fill (),
                        TextAlignment = TextAlignment.Centered,
                        VerticalTextAlignment = VerticalTextAlignment.Middle,
                        Text = "Test"
                    }
                   );

        RunState rs = Application.Begin (window);

        Assert.Null (Application.MouseGrabView);
        Assert.Equal (new Rectangle (0, 0, 10, 3), window.Frame);

        Application.OnMouseEvent (new MouseEvent { X = 0, Y = 0, Flags = MouseFlags.Button1Pressed });

        var firstIteration = false;
        Application.RunIteration (ref rs, ref firstIteration);
        Assert.Equal (window.Border, Application.MouseGrabView);

        Assert.Equal (new Rectangle (0, 0, 10, 3), window.Frame);

        Application.OnMouseEvent (new MouseEvent
        {
            X = 1,
            Y = 1,
            Flags = MouseFlags.Button1Pressed
                    | MouseFlags.ReportMousePosition
        });

        firstIteration = false;
        Application.RunIteration (ref rs, ref firstIteration);
        Assert.Equal (window.Border, Application.MouseGrabView);
        Assert.Equal (new Rectangle (1, 1, 10, 3), window.Frame);

        Application.End (rs);
    }

    [Fact]
    [AutoInitShutdown]
    public void Begin_With_Window_Sets_Size_Correctly ()
    {
        Toplevel top = new ();
        RunState rsTop = Application.Begin (top);
        ((FakeDriver)Application.Driver).SetBufferSize (20, 20);

        var testWindow = new Window { X = 2, Y = 1, Width = 15, Height = 10 };
        Assert.Equal (new Rectangle (2, 1, 15, 10), testWindow.Frame);

        RunState rsTestWindow = Application.Begin (testWindow);
        Assert.Equal (new Rectangle (2, 1, 15, 10), testWindow.Frame);

        Application.End (rsTestWindow);
        Application.End (rsTop);
    }

    // Don't use Dialog as a Top, use a Window instead - dialog has complex layout behavior that is not needed here.
    [Fact]
    [AutoInitShutdown]
    public void Draw_A_Top_Subview_On_A_Window ()
    {
        Toplevel top = new ();
        var win = new Window ();
        top.Add (win);
        RunState rsTop = Application.Begin (top);
        ((FakeDriver)Application.Driver).SetBufferSize (20, 20);

        Assert.Equal (new Rectangle (0, 0, 20, 20), win.Frame);

        var btnPopup = new Button { Text = "Popup" };
        var testWindow = new Window { X = 2, Y = 1, Width = 15, Height = 10 };
        testWindow.Add (btnPopup);

        btnPopup.Accept += (s, e) =>
                            {
                                Rectangle viewToScreen = btnPopup.ViewportToScreen (top.Frame);

                                var viewAddedToTop = new View
                                {
                                    Text = "viewAddedToTop",
                                    X = 1,
                                    Y = viewToScreen.Y + 1,
                                    Width = 18,
                                    Height = 16,
                                    BorderStyle = LineStyle.Single
                                };
                                Assert.Equal (testWindow, Application.Current);
                                Application.Current.DrawContentComplete += OnDrawContentComplete;
                                top.Add (viewAddedToTop);

                                void OnDrawContentComplete (object sender, DrawEventArgs e)
                                {
                                    Assert.Equal (new Rectangle (1, 3, 18, 16), viewAddedToTop.Frame);

                                    Rectangle savedClip = Application.Driver.Clip;
                                    Application.Driver.Clip = top.Frame;
                                    viewAddedToTop.Draw ();
                                    top.Move (2, 15);
                                    View.Driver.AddStr ("One");
                                    top.Move (2, 16);
                                    View.Driver.AddStr ("Two");
                                    top.Move (2, 17);
                                    View.Driver.AddStr ("Three");
                                    Application.Driver.Clip = savedClip;

                                    Application.Current.DrawContentComplete -= OnDrawContentComplete;
                                }
                            };
        RunState rsTestWindow = Application.Begin (testWindow);

        Assert.Equal (new Rectangle (2, 1, 15, 10), testWindow.Frame);

        Application.OnMouseEvent (new () { X = 5, Y = 2, Flags = MouseFlags.Button1Clicked });
        Application.Top.Draw ();

        var firstIteration = false;
        Application.RunIteration (ref rsTestWindow, ref firstIteration);

        TestHelpers.AssertDriverContentsWithFrameAre (
                                                      @$"
┌──────────────────┐
│ ┌─────────────┐  │
│ │{CM.Glyphs.LeftBracket} Popup {CM.Glyphs.RightBracket}    │  │
│┌────────────────┐│
││viewAddedToTop  ││
││                ││
││                ││
││                ││
││                ││
││                ││
││                ││
││                ││
││                ││
││                ││
││                ││
││One             ││
││Two             ││
││Three           ││
│└────────────────┘│
└──────────────────┘",
                                                      _output
                                                     );

        Application.End (rsTestWindow);
        Application.End (rsTop);
    }

    private void OnDrawContentComplete (object sender, DrawEventArgs e) { throw new NotImplementedException (); }

    [Fact]
    [AutoInitShutdown]
    public void Activating_MenuBar_By_Alt_Key_Does_Not_Throw ()
    {
        var menu = new MenuBar
        {
            Menus =
            [
                new MenuBarItem ("Child", new MenuItem [] { new ("_Create Child", "", null) })
            ]
        };
        var topChild = new Toplevel ();
        topChild.Add (menu);
        var top = new Toplevel ();
        top.Add (topChild);
        Application.Begin (top);

        Exception exception = Record.Exception (() => topChild.NewKeyDownEvent (KeyCode.AltMask));
        Assert.Null (exception);
    }

    [Fact]
    [TestRespondersDisposed]
    public void Multi_Thread_Toplevels ()
    {
        Application.Init (new FakeDriver ());

        Toplevel t = new ();
        var w = new Window ();
        t.Add (w);

        int count = 0, count1 = 0, count2 = 0;
        bool log = false, log1 = false, log2 = false;
        var fromTopStillKnowFirstIsRunning = false;
        var fromTopStillKnowSecondIsRunning = false;
        var fromFirstStillKnowSecondIsRunning = false;

        Application.AddTimeout (
                                TimeSpan.FromMilliseconds (100),
                                () =>
                                {
                                    count++;

                                    if (count1 == 5)
                                    {
                                        log1 = true;
                                    }

                                    if (count1 == 14 && count2 == 10 && count == 15)
                                    {
                                        // count2 is already stopped
                                        fromTopStillKnowFirstIsRunning = true;
                                    }

                                    if (count1 == 7 && count2 == 7 && count == 8)
                                    {
                                        fromTopStillKnowSecondIsRunning = true;
                                    }

                                    if (count == 30)
                                    {
                                        Assert.Equal (30, count);
                                        Assert.Equal (20, count1);
                                        Assert.Equal (10, count2);

                                        Assert.True (log);
                                        Assert.True (log1);
                                        Assert.True (log2);

                                        Assert.True (fromTopStillKnowFirstIsRunning);
                                        Assert.True (fromTopStillKnowSecondIsRunning);
                                        Assert.True (fromFirstStillKnowSecondIsRunning);

                                        Application.RequestStop ();

                                        return false;
                                    }

                                    return true;
                                }
                               );

        t.Ready += FirstWindow;

        void FirstWindow (object sender, EventArgs args)
        {
            var firstWindow = new Window ();
            firstWindow.Ready += SecondWindow;

            Application.AddTimeout (
                                    TimeSpan.FromMilliseconds (100),
                                    () =>
                                    {
                                        count1++;

                                        if (count2 == 5)
                                        {
                                            log2 = true;
                                        }

                                        if (count2 == 4 && count1 == 5 && count == 5)
                                        {
                                            fromFirstStillKnowSecondIsRunning = true;
                                        }

                                        if (count1 == 20)
                                        {
                                            Assert.Equal (20, count1);
                                            Application.RequestStop ();

                                            return false;
                                        }

                                        return true;
                                    }
                                   );

            Application.Run (firstWindow);
            firstWindow.Dispose ();
        }

        void SecondWindow (object sender, EventArgs args)
        {
            var testWindow = new Window ();

            Application.AddTimeout (
                                    TimeSpan.FromMilliseconds (100),
                                    () =>
                                    {
                                        count2++;

                                        if (count < 30)
                                        {
                                            log = true;
                                        }

                                        if (count2 == 10)
                                        {
                                            Assert.Equal (10, count2);
                                            Application.RequestStop ();

                                            return false;
                                        }

                                        return true;
                                    }
                                   );

            Application.Run (testWindow);
            testWindow.Dispose ();
        }

        Application.Run (t);
        t.Dispose ();
        Application.Shutdown ();
    }
}