Terminal.Gui/Tests/UnitTests/FileServices/FileDialogTests.cs

using System.IO.Abstractions.TestingHelpers;
using System.Runtime.InteropServices;
using UnitTests;
using Xunit.Abstractions;

namespace Terminal.Gui.FileServicesTests;

public class FileDialogTests ()
{
    [Theory]
    [InlineData (true)]
    [InlineData (false)]
    [AutoInitShutdown]
    public void CancelSelection (bool cancel)
    {
        FileDialog dlg = GetInitializedFileDialog ();
        string openIn = Path.Combine (Environment.CurrentDirectory, "zz");
        Directory.CreateDirectory (openIn);
        dlg.Path = openIn + Path.DirectorySeparatorChar;

        dlg.FilesSelected += (s, e) => e.Cancel = cancel;

        //pressing enter will complete the current selection
        // unless the event cancels the confirm
        Application.RaiseKeyDownEvent (Key.Enter);

        Assert.Equal (cancel, dlg.Canceled);
        dlg.Dispose ();
    }

    [Fact]
    [AutoInitShutdown]
    public void DirectTyping_Allowed ()
    {
        FileDialog dlg = GetInitializedFileDialog ();
        TextField tf = dlg.SubViews.OfType<TextField> ().First (t => t.HasFocus);
        tf.ClearAllSelection ();
        tf.CursorPosition = tf.Text.Length;
        Assert.True (tf.HasFocus);

        SendSlash ();

        Assert.Equal (
                      new DirectoryInfo (Environment.CurrentDirectory + Path.DirectorySeparatorChar).FullName,
                      new DirectoryInfo (dlg.Path + Path.DirectorySeparatorChar).FullName
                     );

        // continue typing the rest of the path
        Send ("Bob");
        Application.RaiseKeyDownEvent ('.');
        Send ("csv");

        Assert.True (dlg.Canceled);

        Application.RaiseKeyDownEvent (Key.Enter);
        Assert.False (dlg.Canceled);
        Assert.Equal ("Bob.csv", Path.GetFileName (dlg.Path));
        dlg.Dispose ();
    }

    [Fact]
    [AutoInitShutdown]
    public void DirectTyping_AutoComplete ()
    {
        FileDialog dlg = GetInitializedFileDialog ();
        string openIn = Path.Combine (Environment.CurrentDirectory, "zz");

        Directory.CreateDirectory (openIn);

        string expectedDest = Path.Combine (openIn, "xx");
        Directory.CreateDirectory (expectedDest);

        dlg.Path = openIn + Path.DirectorySeparatorChar;

        Send ("x");

        // nothing selected yet
        Assert.True (dlg.Canceled);
        Assert.Equal ("x", Path.GetFileName (dlg.Path));

        // complete auto typing
        Application.RaiseKeyDownEvent ('\t');

        // but do not close dialog
        Assert.True (dlg.Canceled);
        Assert.EndsWith ("xx" + Path.DirectorySeparatorChar, dlg.Path);

        // press enter again to confirm the dialog
        Application.RaiseKeyDownEvent (Key.Enter);
        Assert.False (dlg.Canceled);
        Assert.EndsWith ("xx" + Path.DirectorySeparatorChar, dlg.Path);
        dlg.Dispose ();
    }

    [Fact]
    [AutoInitShutdown]
    public void DoNotConfirmSelectionWhenFindFocused ()
    {
        FileDialog dlg = GetInitializedFileDialog ();
        string openIn = Path.Combine (Environment.CurrentDirectory, "zz");
        Directory.CreateDirectory (openIn);
        dlg.Path = openIn + Path.DirectorySeparatorChar;

        var tf = GetTextField (dlg, FileDialogPart.SearchField);
        tf.SetFocus ();

        Assert.IsType<TextField> (dlg.MostFocused);
        Assert.Same (tf, dlg.MostFocused);

        Assert.Equal ("Enter Search", tf.Caption);

        // Dialog has not yet been confirmed with a choice
        Assert.True (dlg.Canceled);

        //pressing enter while search focused should not confirm path
        Application.RaiseKeyDownEvent (Key.Enter);

        Assert.True (dlg.Canceled);

        // tabbing out of search 
        Application.RaiseKeyDownEvent ('\t');

        //should allow enter to confirm path
        Application.RaiseKeyDownEvent (Key.Enter);

        // Dialog has not yet been confirmed with a choice
        Assert.False (dlg.Canceled);
        dlg.Dispose ();
    }

    [Fact]
    [AutoInitShutdown]
    public void DotDot_MovesToRoot_ThenPressBack ()
    {
        FileDialog dlg = GetDialog ();
        dlg.OpenMode = OpenMode.Directory;
        dlg.AllowsMultipleSelection = true;
        var selected = false;
        dlg.FilesSelected += (s, e) => { selected = true; };

        AssertIsTheStartingDirectory (dlg.Path);

        Assert.IsType<TextField> (dlg.MostFocused);
        Application.RaiseKeyDownEvent (Key.CursorDown);

        var tv = GetTableView(dlg);
        tv.SetFocus ();

        Assert.IsType<TableView> (dlg.MostFocused);

        // ".." should be the first thing selected
        // ".." should not mess with the displayed path
        AssertIsTheStartingDirectory (dlg.Path);

        // Accept navigation up a directory
        Application.RaiseKeyDownEvent (Key.Enter);

        AssertIsTheRootDirectory (dlg.Path);

        Assert.True (dlg.Canceled);
        Assert.False (selected);

        Assert.IsType<TableView> (dlg.MostFocused);

        // Now press Backspace (in table view)
        Application.RaiseKeyDownEvent (Key.Backspace);

        // Should move us back to the root
        AssertIsTheStartingDirectory (dlg.Path);

        Assert.True (dlg.Canceled);
        Assert.False (selected);
        dlg.Dispose ();
    }

    [Theory]
    [AutoInitShutdown]
    [InlineData (true)]
    [InlineData (false)]
    public void MultiSelectDirectory_CannotToggleDotDot (bool acceptWithEnter)
    {
        FileDialog dlg = GetDialog ();
        dlg.OpenMode = OpenMode.Directory;
        dlg.AllowsMultipleSelection = true;
        IReadOnlyCollection<string> eventMultiSelected = null;
        dlg.FilesSelected += (s, e) => { eventMultiSelected = e.Dialog.MultiSelected; };


        var tv = GetTableView (dlg);
        tv.SetFocus ();

        Assert.IsType<TableView> (dlg.MostFocused);

        // Try to toggle '..'
        Application.RaiseKeyDownEvent (' ');
        Application.RaiseKeyDownEvent (Key.CursorDown);

        // Toggle subfolder
        Application.RaiseKeyDownEvent (' ');

        Assert.True (dlg.Canceled);

        if (acceptWithEnter)
        {
            Application.RaiseKeyDownEvent (Key.Enter);
        }
        else
        {
            Application.RaiseKeyDownEvent ('O');
        }

        Assert.False (dlg.Canceled);

        Assert.Multiple (
                         () =>
                         {
                             // Only the subfolder should be selected
                             Assert.Single (dlg.MultiSelected);
                             AssertIsTheSubfolder (dlg.Path);
                             AssertIsTheSubfolder (dlg.MultiSelected.Single ());
                         },
                         () =>
                         {
                             // Event should also agree with the final state
                             Assert.NotNull (eventMultiSelected);
                             Assert.Single (eventMultiSelected);
                             AssertIsTheSubfolder (eventMultiSelected.Single ());
                         }
                        );
        dlg.Dispose ();
    }

    [Theory]
    [AutoInitShutdown]
    [InlineData (true)]
    [InlineData (false)]
    public void MultiSelectDirectory_CanToggleThenAccept (bool acceptWithEnter)
    {
        FileDialog dlg = GetDialog ();
        dlg.OpenMode = OpenMode.Directory;
        dlg.AllowsMultipleSelection = true;
        IReadOnlyCollection<string> eventMultiSelected = null;
        dlg.FilesSelected += (s, e) => { eventMultiSelected = e.Dialog.MultiSelected; };

        var tv = GetTableView (dlg);
        tv.SetFocus ();

        Assert.IsType<TableView> (dlg.MostFocused);

        // Move selection to subfolder
        Application.RaiseKeyDownEvent (Key.CursorDown);

        // Toggle subfolder
        Application.RaiseKeyDownEvent (' ');

        Assert.True (dlg.Canceled);

        if (acceptWithEnter)
        {
            Application.RaiseKeyDownEvent (Key.Enter);
        }
        else
        {
            Application.RaiseKeyDownEvent (Key.O.WithAlt);
        }

        Assert.False (dlg.Canceled);

        Assert.Multiple (
                         () =>
                         {
                             // Only the subfolder should be selected
                             Assert.Single (dlg.MultiSelected);
                             AssertIsTheSubfolder (dlg.Path);
                             AssertIsTheSubfolder (dlg.MultiSelected.Single ());
                         },
                         () =>
                         {
                             // Event should also agree with the final state
                             Assert.NotNull (eventMultiSelected);
                             Assert.Single (eventMultiSelected);
                             AssertIsTheSubfolder (eventMultiSelected.Single ());
                         }
                        );
        dlg.Dispose ();
    }

    [Fact]
    [AutoInitShutdown]
    public void MultiSelectDirectory_EnterOpensFolder ()
    {
        FileDialog dlg = GetDialog ();
        dlg.OpenMode = OpenMode.Directory;
        dlg.AllowsMultipleSelection = true;
        IReadOnlyCollection<string> eventMultiSelected = null;
        dlg.FilesSelected += (s, e) => { eventMultiSelected = e.Dialog.MultiSelected; };

        var tv = GetTableView (dlg);
        tv.SetFocus ();

        Assert.IsType<TableView> (dlg.MostFocused);

        // Move selection to subfolder
        Application.RaiseKeyDownEvent (Key.CursorDown);

        Application.RaiseKeyDownEvent (Key.Enter);

        // Path should update to the newly opened folder
        AssertIsTheSubfolder (dlg.Path);

        // No selection will have been confirmed
        Assert.True (dlg.Canceled);
        Assert.Empty (dlg.MultiSelected);
        Assert.Null (eventMultiSelected);
        dlg.Dispose ();
    }

    [Fact]
    [AutoInitShutdown]
    public void OnLoad_TextBoxIsFocused ()
    {
        FileDialog dlg = GetInitializedFileDialog ();

        View tf = dlg.SubViews.FirstOrDefault (t => t.HasFocus);
        Assert.NotNull (tf);
        Assert.IsType<TextField> (tf);
        dlg.Dispose ();
    }

    [Theory]
    [AutoInitShutdown]
    [InlineData (true, true)]
    [InlineData (true, false)]
    [InlineData (false, true)]
    [InlineData (false, false)]
    public void PickDirectory_ArrowNavigation (bool openModeMixed, bool multiple)
    {
        FileDialog dlg = GetDialog ();
        dlg.OpenMode = openModeMixed ? OpenMode.Mixed : OpenMode.Directory;
        dlg.AllowsMultipleSelection = multiple;

        var tv = GetTableView (dlg);
        tv.SetFocus ();

        Assert.IsType<TableView> (dlg.MostFocused);

        // Should be selecting ..
        Application.RaiseKeyDownEvent (Key.CursorDown);

        // Down to the directory
        Assert.True (dlg.Canceled);

        // Alt+O to open (enter would just navigate into the child dir)
        Application.RaiseKeyDownEvent (Key.O.WithAlt);
        Assert.False (dlg.Canceled);

        AssertIsTheSubfolder (dlg.Path);
        dlg.Dispose ();
    }

    [Theory]
    [AutoInitShutdown]
    [InlineData (true, true)]
    [InlineData (true, false)]
    [InlineData (false, true)]
    [InlineData (false, false)]
    public void PickDirectory_DirectTyping (bool openModeMixed, bool multiple)
    {
        FileDialog dlg = GetDialog ();
        dlg.OpenMode = openModeMixed ? OpenMode.Mixed : OpenMode.Directory;
        dlg.AllowsMultipleSelection = multiple;

        // whe first opening the text field will have select all on
        // so to add to current path user must press End or right
        Application.RaiseKeyDownEvent (Key.CursorLeft);
        Application.RaiseKeyDownEvent (Key.CursorRight);

        Send ("subfolder");

        // Dialog has not yet been confirmed with a choice
        Assert.True (dlg.Canceled);

        // Now it has
        Application.RaiseKeyDownEvent (Key.Enter);
        Assert.False (dlg.Canceled);
        AssertIsTheSubfolder (dlg.Path);
        dlg.Dispose ();
    }

    [Theory]
    [InlineData (".csv", null, false)]
    [InlineData (".csv", "", false)]
    [InlineData (".csv", "c:\\MyFile.csv", true)]
    [InlineData (".csv", "c:\\MyFile.CSV", true)]
    [InlineData (".csv", "c:\\MyFile.csv.bak", false)]
    public void TestAllowedType_Basic (string allowed, string candidate, bool expected)
    {
        Assert.Equal (expected, new AllowedType ("Test", allowed).IsAllowed (candidate));
    }

    [Theory]
    [InlineData (".Designer.cs", "c:\\MyView.Designer.cs", true)]
    [InlineData (".Designer.cs", "c:\\temp/MyView.Designer.cs", true)]
    [InlineData (".Designer.cs", "MyView.Designer.cs", true)]
    [InlineData (".Designer.cs", "c:\\MyView.DESIGNER.CS", true)]
    [InlineData (".Designer.cs", "MyView.cs", false)]
    public void TestAllowedType_DoubleBarreled (string allowed, string candidate, bool expected)
    {
        Assert.Equal (expected, new AllowedType ("Test", allowed).IsAllowed (candidate));
    }

    [Theory]
    [InlineData ("Dockerfile", "c:\\temp\\Dockerfile", true)]
    [InlineData ("Dockerfile", "Dockerfile", true)]
    [InlineData ("Dockerfile", "someimg.Dockerfile", true)]
    public void TestAllowedType_SpecificFile (string allowed, string candidate, bool expected)
    {
        Assert.Equal (expected, new AllowedType ("Test", allowed).IsAllowed (candidate));
    }

    [Fact]
    [AutoInitShutdown]
    public void TestDirectoryContents_Linux ()
    {
        if (IsWindows ())
        {
            return;
        }

        FileDialog fd = GetLinuxDialog ();
        fd.Title = string.Empty;

        fd.Style.Culture = new ("en-US");

        fd.Draw ();

        /*
         *
         *
           ┌─────────────────────────────────────────────────────────────────────────┐
           │/demo/                                                                   │
           │⟦▲⟧                                                                      │
           │┌────────────┬──────────┬──────────────────────────────┬────────────────┐│
           ││Filename (▲)│Size      │Modified                      │Type            ││
           │├────────────┼──────────┼──────────────────────────────┼────────────────┤│
           ││..          │          │                              │<Directory>     ││
           ││/subfolder  │          │2002-01-01T22:42:10           │<Directory>     ││
           ││image.gif   │4.00 B    │2002-01-01T22:42:10           │.gif            ││
           ││jQuery.js   │7.00 B    │2001-01-01T11:44:42           │.js             ││
           │                                                                         │
           │                                                                         │
           │                                                                         │
           │⟦ ►► ⟧ Enter Search                                 ⟦► OK ◄⟧ ⟦ Cancel ⟧  │
           └─────────────────────────────────────────────────────────────────────────┘

         *
         */

        var path = GetTextField (fd, FileDialogPart.Path);
        Assert.Equal ("/demo/", path.Text);

        var tv = GetTableView (fd);

        // Asserting the headers
        Assert.Equal ("Filename (▲)", tv.Table.ColumnNames.ElementAt (0));
        Assert.Equal ("Size", tv.Table.ColumnNames.ElementAt (1));
        Assert.Equal ("Modified", tv.Table.ColumnNames.ElementAt (2));
        Assert.Equal ("Type", tv.Table.ColumnNames.ElementAt (3));

        // Asserting the table contents
        Assert.Equal ("..", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [0, 0]));
        Assert.Equal ("/subfolder", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [1, 0]));
        Assert.Equal ("image.gif", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [2, 0]));
        Assert.Equal ("jQuery.js", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [3, 0]));

        Assert.Equal ("", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [0, 1]));
        Assert.Equal ("", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [1, 1]));
        Assert.Equal ("4.00 B", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [2, 1]));
        Assert.Equal ("7.00 B", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [3, 1]));

        Assert.Equal ("", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [0, 2]));
        Assert.Equal ("2002-01-01T22:42:10", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [1, 2]));
        Assert.Equal ("2002-01-01T22:42:10", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [2, 2]));
        Assert.Equal ("2001-01-01T11:44:42", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [3, 2]));

        Assert.Equal ("<Directory>", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [0, 3]));
        Assert.Equal ("<Directory>", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [1, 3]));
        Assert.Equal (".gif", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [2, 3]));
        Assert.Equal (".js", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [3, 3]));

        fd.Dispose ();
    }

    [Fact]
    [AutoInitShutdown]
    public void TestDirectoryContents_Windows ()
    {
        if (!IsWindows ())
        {
            return;
        }

        FileDialog fd = GetWindowsDialog ();
        fd.Title = string.Empty;

        fd.Style.Culture = new ("en-US");

        fd.Draw ();

        /*
         *
         *
           ┌─────────────────────────────────────────────────────────────────────────┐
           │c:\demo\                                                                 │
           │⟦▲⟧                                                                      │
           │┌────────────┬──────────┬──────────────────────────────┬────────────────┐│
           ││Filename (▲)│Size      │Modified                      │Type            ││
           │├────────────┼──────────┼──────────────────────────────┼────────────────┤│
           ││..          │          │                              │<Directory>     ││
           ││\subfolder  │          │2002-01-01T22:42:10           │<Directory>     ││
           ││image.gif   │4.00 B    │2002-01-01T22:42:10           │.gif            ││
           ││jQuery.js   │7.00 B    │2001-01-01T11:44:42           │.js             ││
           ││mybinary.exe│7.00 B    │2001-01-01T11:44:42           │.exe            ││
           │                                                                         │
           │                                                                         │
           │⟦ ►► ⟧ Enter Search                                 ⟦► OK ◄⟧ ⟦ Cancel ⟧  │
           └─────────────────────────────────────────────────────────────────────────┘
           
         *
         */

        var path = GetTextField (fd, FileDialogPart.Path);
        Assert.Equal ("c:\\demo\\",path.Text);

        var tv = GetTableView (fd);

        // Asserting the headers
        Assert.Equal ("Filename (▲)", tv.Table.ColumnNames.ElementAt (0));
        Assert.Equal ("Size", tv.Table.ColumnNames.ElementAt (1));
        Assert.Equal ("Modified", tv.Table.ColumnNames.ElementAt (2));
        Assert.Equal ("Type", tv.Table.ColumnNames.ElementAt (3));

        // Asserting the table contents
        Assert.Equal ("..", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [0, 0]));
        Assert.Equal (@"\subfolder", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [1, 0]));
        Assert.Equal ("image.gif", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [2, 0]));
        Assert.Equal ("jQuery.js", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [3, 0]));
        Assert.Equal ("mybinary.exe", tv.Style.GetOrCreateColumnStyle (0).GetRepresentation (tv.Table [4, 0]));

        Assert.Equal ("", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [0, 1]));
        Assert.Equal ("", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [1, 1]));
        Assert.Equal ("4.00 B", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [2, 1]));
        Assert.Equal ("7.00 B", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [3, 1]));
        Assert.Equal ("7.00 B", tv.Style.GetOrCreateColumnStyle (1).GetRepresentation (tv.Table [4, 1]));

        Assert.Equal ("", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [0, 2]));
        Assert.Equal ("2002-01-01T22:42:10", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [1, 2]));
        Assert.Equal ("2002-01-01T22:42:10", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [2, 2]));
        Assert.Equal ("2001-01-01T11:44:42", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [3, 2]));
        Assert.Equal ("2001-01-01T11:44:42", tv.Style.GetOrCreateColumnStyle (2).GetRepresentation (tv.Table [4, 2]));

        Assert.Equal ("<Directory>", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [0, 3]));
        Assert.Equal ("<Directory>", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [1, 3]));
        Assert.Equal (".gif", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [2, 3]));
        Assert.Equal (".js", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [3, 3]));
        Assert.Equal (".exe", tv.Style.GetOrCreateColumnStyle (3).GetRepresentation (tv.Table [4, 3]));

        fd.Dispose ();
    }

    private void AssertIsTheRootDirectory (string path)
    {
        if (IsWindows ())
        {
            Assert.Equal (@"c:\", path);
        }
        else
        {
            Assert.Equal ("/", path);
        }
    }

    private void AssertIsTheStartingDirectory (string path)
    {
        if (IsWindows ())
        {
            Assert.Equal (@"c:\demo\", path);
        }
        else
        {
            Assert.Equal ("/demo/", path);
        }
    }

    private void AssertIsTheSubfolder (string path)
    {
        if (IsWindows ())
        {
            Assert.Equal (@"c:\demo\subfolder", path);
        }
        else
        {
            Assert.Equal ("/demo/subfolder", path);
        }
    }

    private void Begin (FileDialog dlg)
    {
        dlg.BeginInit ();
        dlg.EndInit ();
        Application.Begin (dlg);
    }

    private FileDialog GetDialog () { return IsWindows () ? GetWindowsDialog () : GetLinuxDialog (); }

    private FileDialog GetInitializedFileDialog ()
    {

        Window.DefaultBorderStyle = LineStyle.Single;
        Dialog.DefaultButtonAlignment = Alignment.Center;
        Dialog.DefaultBorderStyle = LineStyle.Single;
        Dialog.DefaultShadow = ShadowStyle.None;
        Button.DefaultShadow = ShadowStyle.None;

        var dlg = new FileDialog ();
        Begin (dlg);

        return dlg;
    }

    private FileDialog GetLinuxDialog ()
    {
        Window.DefaultBorderStyle = LineStyle.Single;
        Dialog.DefaultButtonAlignment = Alignment.Center;
        Dialog.DefaultBorderStyle = LineStyle.Single;
        Dialog.DefaultShadow = ShadowStyle.None;
        Button.DefaultShadow = ShadowStyle.None;

        // Arrange
        var fileSystem = new MockFileSystem (new Dictionary<string, MockFileData> (), "/");
        fileSystem.MockTime (() => new (2010, 01, 01, 11, 12, 43));

        fileSystem.AddFile (
                            @"/myfile.txt",
                            new ("Testing is meh.") { LastWriteTime = new DateTime (2001, 01, 01, 11, 12, 11) }
                           );

        fileSystem.AddFile (
                            @"/demo/jQuery.js",
                            new ("some js") { LastWriteTime = new DateTime (2001, 01, 01, 11, 44, 42) }
                           );

        fileSystem.AddFile (
                            @"/demo/image.gif",
                            new (new byte [] { 0x12, 0x34, 0x56, 0xd2 })
                            {
                                LastWriteTime = new DateTime (2002, 01, 01, 22, 42, 10)
                            }
                           );

        var m = (MockDirectoryInfo)fileSystem.DirectoryInfo.New (@"/demo/subfolder");
        m.Create ();
        m.LastWriteTime = new (2002, 01, 01, 22, 42, 10);

        fileSystem.AddFile (
                            @"/demo/subfolder/image2.gif",
                            new (new byte [] { 0x12, 0x34, 0x56, 0xd2 })
                            {
                                LastWriteTime = new DateTime (2002, 01, 01, 22, 42, 10)
                            }
                           );

        var fd = new FileDialog (fileSystem) { Height = 15, Width = 75 };
        fd.Path = @"/demo/";
        Begin (fd);

        return fd;
    }

    private FileDialog GetWindowsDialog ()
    {
        // Override CM
        Window.DefaultBorderStyle = LineStyle.Single;
        Dialog.DefaultButtonAlignment = Alignment.Center;
        Dialog.DefaultBorderStyle = LineStyle.Single;
        Dialog.DefaultShadow = ShadowStyle.None;
        Button.DefaultShadow = ShadowStyle.None;

        // Arrange
        var fileSystem = new MockFileSystem (new Dictionary<string, MockFileData> (), @"c:\");
        fileSystem.MockTime (() => new (2010, 01, 01, 11, 12, 43));

        fileSystem.AddFile (
                            @"c:\myfile.txt",
                            new ("Testing is meh.") { LastWriteTime = new DateTime (2001, 01, 01, 11, 12, 11) }
                           );

        fileSystem.AddFile (
                            @"c:\demo\jQuery.js",
                            new ("some js") { LastWriteTime = new DateTime (2001, 01, 01, 11, 44, 42) }
                           );

        fileSystem.AddFile (
                            @"c:\demo\mybinary.exe",
                            new ("some js") { LastWriteTime = new DateTime (2001, 01, 01, 11, 44, 42) }
                           );

        fileSystem.AddFile (
                            @"c:\demo\image.gif",
                            new (new byte [] { 0x12, 0x34, 0x56, 0xd2 })
                            {
                                LastWriteTime = new DateTime (2002, 01, 01, 22, 42, 10)
                            }
                           );

        var m = (MockDirectoryInfo)fileSystem.DirectoryInfo.New (@"c:\demo\subfolder");
        m.Create ();
        m.LastWriteTime = new (2002, 01, 01, 22, 42, 10);

        fileSystem.AddFile (
                            @"c:\demo\subfolder\image2.gif",
                            new (new byte [] { 0x12, 0x34, 0x56, 0xd2 })
                            {
                                LastWriteTime = new DateTime (2002, 01, 01, 22, 42, 10)
                            }
                           );

        var fd = new FileDialog (fileSystem) { Height = 15, Width = 75 };
        fd.Path = @"c:\demo\";
        Begin (fd);

        return fd;
    }
    /*
            [Fact, AutoInitShutdown]
            public void Autocomplete_NoSuggestion_WhenTextMatchesExactly ()
            {
                var tb = new TextFieldWithAppendAutocomplete ();
                ForceFocus (tb);

                tb.Text = "/bob/fish";
                tb.CursorPosition = tb.Text.Length;
                tb.GenerateSuggestions (null, "fish", "fishes");

                // should not report success for autocompletion because we already have that exact
                // string
                Assert.False (tb.AcceptSelectionIfAny ());
            }

            [Fact, AutoInitShutdown]
            public void Autocomplete_AcceptSuggstion ()
            {
                var tb = new TextFieldWithAppendAutocomplete ();
                ForceFocus (tb);

                tb.Text = @"/bob/fi";
                tb.CursorPosition = tb.Text.Length;
                tb.GenerateSuggestions (null, "fish", "fishes");

                Assert.True (tb.AcceptSelectionIfAny ());
                Assert.Equal (@"/bob/fish", tb.Text);
            }*/

    private bool IsWindows () { return RuntimeInformation.IsOSPlatform (OSPlatform.Windows); }

    private void Send (string chars)
    {
        foreach (char ch in chars)
        {
            Application.RaiseKeyDownEvent (ch);
        }
    }

    private void SendSlash ()
    {
        if (Path.DirectorySeparatorChar == '/')
        {
            Application.RaiseKeyDownEvent ('/');
        }
        else
        {
            Application.RaiseKeyDownEvent ('\\');
        }
    }

    private TextField GetTextField (FileDialog dlg, FileDialogPart part)
    {
        switch (part)
        {
            case FileDialogPart.Path:
                return dlg.SubViews.OfType<TextField> ().ElementAt (0);
            case FileDialogPart.SearchField:
                return dlg.SubViews.OfType<TextField> ().ElementAt (1);
            default:
                throw new ArgumentOutOfRangeException (nameof (part), part, null);
        }
    }

    private TableView GetTableView (FileDialog dlg)
    {
        var tile = dlg.SubViews.OfType<TileView> ().Single ();
        return (TableView)tile.Tiles.ElementAt (1).ContentView.SubViews.ElementAt(0);
    }

    private enum FileDialogPart
    {
        Path,
        SearchField,
    }
}