private void MainWindow_OnPreviewKeyDown(object sender, KeyEventArgs e)
        {
            bool handled = true;

            switch (e.Key)
            {
            case Key.Enter:
            {
                ToggleFullscreen();
                break;
            }

            case Key.Escape:
            {
                SetFullscreen(false);
                break;
            }

            case Key.Space:
            {
                ViewModel.TogglePlayback();
                break;
            }

            case Key.Left:
            {
                ViewModel.ShiftPosition(TimeSpan.FromSeconds(-5));
                break;
            }

            case Key.Right:
            {
                ViewModel.ShiftPosition(TimeSpan.FromSeconds(5));
                break;
            }

            case Key.Up:
            {
                ViewModel.VolumeUp();
                break;
            }

            case Key.Down:
            {
                ViewModel.VolumeDown();
                break;
            }

            case Key.NumPad0:
            {
                break;
            }

            case Key.NumPad1:
            {
                VideoPlayer.ChangeZoom(-0.02);
                break;
            }

            case Key.NumPad2:
            {
                VideoPlayer.Move(new Point(0, 1));
                break;
            }

            case Key.NumPad3:
            {
                break;
            }

            case Key.NumPad4:
            {
                VideoPlayer.Move(new Point(-1, 0));
                break;
            }

            case Key.NumPad5:
            {
                VideoPlayer.ResetTransform();
                break;
            }

            case Key.NumPad6:
            {
                VideoPlayer.Move(new Point(1, 0));
                break;
            }

            case Key.NumPad7:
            {
                VideoPlayer.SideBySide ^= true;
                break;
            }

            case Key.NumPad8:
            {
                VideoPlayer.Move(new Point(0, -1));
                break;
            }

            case Key.NumPad9:
            {
                VideoPlayer.ChangeZoom(0.02);
                break;
            }

            default:
            {
                handled = false;
                break;
            }
            }

            e.Handled = handled;
        }