Terminal.Gui/UICatalog/Scenarios/AllViewsTester.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Terminal.Gui;

namespace UICatalog.Scenarios;

[ScenarioMetadata ("All Views Tester", "Provides a test UI for all classes derived from View.")]
[ScenarioCategory ("Layout")]
[ScenarioCategory ("Tests")]
[ScenarioCategory ("Top Level Windows")]
public class AllViewsTester : Scenario {
	FrameView _leftPane;
	ListView _classListView;
	FrameView _hostPane;

	Dictionary<string, Type> _viewClasses;
	View _curView = null;

	// Settings
	FrameView _settingsPane;
	CheckBox _computedCheckBox;
	FrameView _locationFrame;
	RadioGroup _xRadioGroup;
	TextField _xText;
	int _xVal = 0;
	RadioGroup _yRadioGroup;
	TextField _yText;
	int _yVal = 0;

	FrameView _sizeFrame;
	RadioGroup _wRadioGroup;
	TextField _wText;
	int _wVal = 0;
	RadioGroup _hRadioGroup;
	TextField _hText;
	int _hVal = 0;

	public override void Init ()
	{
		// Don't create a sub-win (Scenario.Win); just use Application.Top
		Application.Init ();
		ConfigurationManager.Themes.Theme = Theme;
		ConfigurationManager.Apply ();
		Application.Top.ColorScheme = Colors.ColorSchemes [TopLevelColorScheme];
	}

	public override void Setup ()
	{
		var statusBar = new StatusBar (new StatusItem [] {
			new (Application.QuitKey, $"{Application.QuitKey} to Quit", () => Quit ()),
			new (KeyCode.F2, "~F2~ Toggle Frame Ruler", () => {
				ConsoleDriver.Diagnostics ^= ConsoleDriver.DiagnosticFlags.FrameRuler;
				Application.Top.SetNeedsDisplay ();
			}),
			new (KeyCode.F3, "~F3~ Toggle Frame Padding", () => {
				ConsoleDriver.Diagnostics ^= ConsoleDriver.DiagnosticFlags.FramePadding;
				Application.Top.SetNeedsDisplay ();
			})
		});
		Application.Top.Add (statusBar);

		_viewClasses = GetAllViewClassesCollection ()
				.OrderBy (t => t.Name)
				.Select (t => new KeyValuePair<string, Type> (t.Name, t))
				.ToDictionary (t => t.Key, t => t.Value);

		_leftPane = new FrameView ("Classes") {
			X = 0,
			Y = 0,
			Width = 15,
			Height = Dim.Fill (1), // for status bar
			CanFocus = false,
			ColorScheme = Colors.TopLevel
		};

		_classListView = new ListView (_viewClasses.Keys.ToList ()) {
			X = 0,
			Y = 0,
			Width = Dim.Fill (0),
			Height = Dim.Fill (0),
			AllowsMarking = false,
			ColorScheme = Colors.TopLevel,
			SelectedItem = 0
		};
		_classListView.OpenSelectedItem += (s, a) => {
			_settingsPane.SetFocus ();
		};
		_classListView.SelectedItemChanged += (s, args) => {
			// Remove existing class, if any
			if (_curView != null) {
				_curView.LayoutComplete -= LayoutCompleteHandler;
				_hostPane.Remove (_curView);
				_curView.Dispose ();
				_curView = null;
				_hostPane.Clear ();
			}
			_curView = CreateClass (_viewClasses.Values.ToArray () [_classListView.SelectedItem]);
		};
		_leftPane.Add (_classListView);

		_settingsPane = new FrameView ("Settings") {
			X = Pos.Right (_leftPane),
			Y = 0, // for menu
			Width = Dim.Fill (),
			Height = 10,
			CanFocus = false,
			ColorScheme = Colors.TopLevel
		};
		_computedCheckBox = new CheckBox ("Computed Layout", true) { X = 0, Y = 0 };
		_computedCheckBox.Toggled += (s, e) => {
			if (_curView != null) {
				_curView.LayoutStyle = e.OldValue == true ? LayoutStyle.Absolute : LayoutStyle.Computed;
				_hostPane.LayoutSubviews ();
			}
		};
		_settingsPane.Add (_computedCheckBox);

		string [] radioItems = new string [] { "Percent(x)", "AnchorEnd(x)", "Center", "At(x)" };
		_locationFrame = new FrameView ("Location (Pos)") {
			X = Pos.Left (_computedCheckBox),
			Y = Pos.Bottom (_computedCheckBox),
			Height = 3 + radioItems.Length,
			Width = 36
		};
		_settingsPane.Add (_locationFrame);

		var label = new Label ("x:") { X = 0, Y = 0 };
		_locationFrame.Add (label);
		_xRadioGroup = new RadioGroup (radioItems) {
			X = 0,
			Y = Pos.Bottom (label)
		};
		_xRadioGroup.SelectedItemChanged += (s, selected) => DimPosChanged (_curView);
		_xText = new TextField ($"{_xVal}") { X = Pos.Right (label) + 1, Y = 0, Width = 4 };
		_xText.TextChanged += (s, args) => {
			try {
				_xVal = int.Parse (_xText.Text);
				DimPosChanged (_curView);
			} catch { }
		};
		_locationFrame.Add (_xText);

		_locationFrame.Add (_xRadioGroup);

		radioItems = new string [] { "Percent(y)", "AnchorEnd(y)", "Center", "At(y)" };
		label = new Label ("y:") { X = Pos.Right (_xRadioGroup) + 1, Y = 0 };
		_locationFrame.Add (label);
		_yText = new TextField ($"{_yVal}") { X = Pos.Right (label) + 1, Y = 0, Width = 4 };
		_yText.TextChanged += (s, args) => {
			try {
				_yVal = int.Parse (_yText.Text);
				DimPosChanged (_curView);
			} catch { }
		};
		_locationFrame.Add (_yText);
		_yRadioGroup = new RadioGroup (radioItems) {
			X = Pos.X (label),
			Y = Pos.Bottom (label)
		};
		_yRadioGroup.SelectedItemChanged += (s, selected) => DimPosChanged (_curView);
		_locationFrame.Add (_yRadioGroup);

		_sizeFrame = new FrameView ("Size (Dim)") {
			X = Pos.Right (_locationFrame),
			Y = Pos.Y (_locationFrame),
			Height = 3 + radioItems.Length,
			Width = 40
		};

		radioItems = new string [] { "Percent(width)", "Fill(width)", "Sized(width)" };
		label = new Label ("width:") { X = 0, Y = 0 };
		_sizeFrame.Add (label);
		_wRadioGroup = new RadioGroup (radioItems) {
			X = 0,
			Y = Pos.Bottom (label)
		};
		_wRadioGroup.SelectedItemChanged += (s, selected) => DimPosChanged (_curView);
		_wText = new TextField ($"{_wVal}") { X = Pos.Right (label) + 1, Y = 0, Width = 4 };
		_wText.TextChanged += (s, args) => {
			try {
				switch (_wRadioGroup.SelectedItem) {
				case 0:
					_wVal = Math.Min (int.Parse (_wText.Text), 100);
					break;
				case 1:
				case 2:
					_wVal = int.Parse (_wText.Text);
					break;
				}
				DimPosChanged (_curView);
			} catch { }
		};
		_sizeFrame.Add (_wText);
		_sizeFrame.Add (_wRadioGroup);

		radioItems = new string [] { "Percent(height)", "Fill(height)", "Sized(height)" };
		label = new Label ("height:") { X = Pos.Right (_wRadioGroup) + 1, Y = 0 };
		_sizeFrame.Add (label);
		_hText = new TextField ($"{_hVal}") { X = Pos.Right (label) + 1, Y = 0, Width = 4 };
		_hText.TextChanged += (s, args) => {
			try {
				switch (_hRadioGroup.SelectedItem) {
				case 0:
					_hVal = Math.Min (int.Parse (_hText.Text), 100);
					break;
				case 1:
				case 2:
					_hVal = int.Parse (_hText.Text);
					break;
				}
				DimPosChanged (_curView);
			} catch { }
		};
		_sizeFrame.Add (_hText);

		_hRadioGroup = new RadioGroup (radioItems) {
			X = Pos.X (label),
			Y = Pos.Bottom (label)
		};
		_hRadioGroup.SelectedItemChanged += (s, selected) => DimPosChanged (_curView);
		_sizeFrame.Add (_hRadioGroup);

		_settingsPane.Add (_sizeFrame);

		_hostPane = new FrameView ("") {
			X = Pos.Right (_leftPane),
			Y = Pos.Bottom (_settingsPane),
			Width = Dim.Fill (),
			Height = Dim.Fill (1), // + 1 for status bar
			ColorScheme = Colors.Dialog
		};

		Application.Top.Add (_leftPane, _settingsPane, _hostPane);

		_curView = CreateClass (_viewClasses.First ().Value);
	}

	void DimPosChanged (View view)
	{
		if (view == null) {
			return;
		}

		var layout = view.LayoutStyle;

		try {
			view.LayoutStyle = LayoutStyle.Absolute;

			view.X = _xRadioGroup.SelectedItem switch {
				0 => Pos.Percent (_xVal),
				1 => Pos.AnchorEnd (_xVal),
				2 => Pos.Center (),
				3 => Pos.At (_xVal),
				_ => view.X
			};

			view.Y = _yRadioGroup.SelectedItem switch {
				0 => Pos.Percent (_yVal),
				1 => Pos.AnchorEnd (_yVal),
				2 => Pos.Center (),
				3 => Pos.At (_yVal),
				_ => view.Y
			};

			view.Width = _wRadioGroup.SelectedItem switch {
				0 => Dim.Percent (_wVal),
				1 => Dim.Fill (_wVal),
				2 => Dim.Sized (_wVal),
				_ => view.Width
			};

			view.Height = _hRadioGroup.SelectedItem switch {
				0 => Dim.Percent (_hVal),
				1 => Dim.Fill (_hVal),
				2 => Dim.Sized (_hVal),
				_ => view.Height
			};
		} catch (Exception e) {
			MessageBox.ErrorQuery ("Exception", e.Message, "Ok");
		} finally {
			view.LayoutStyle = layout;
		}
		UpdateTitle (view);
	}

	// TODO: This is missing some
	List<string> _posNames = new() { "Factor", "AnchorEnd", "Center", "Absolute" };
	List<string> _dimNames = new() { "Factor", "Fill", "Absolute" };

	void UpdateSettings (View view)
	{
		string x = view.X.ToString ();
		string y = view.Y.ToString ();
		_xRadioGroup.SelectedItem = _posNames.IndexOf (_posNames.Where (s => x.Contains (s)).First ());
		_yRadioGroup.SelectedItem = _posNames.IndexOf (_posNames.Where (s => y.Contains (s)).First ());
		_xText.Text = $"{view.Frame.X}";
		_yText.Text = $"{view.Frame.Y}";

		string w = view.Width.ToString ();
		string h = view.Height.ToString ();
		_wRadioGroup.SelectedItem = _dimNames.IndexOf (_dimNames.Where (s => w.Contains (s)).First ());
		_hRadioGroup.SelectedItem = _dimNames.IndexOf (_dimNames.Where (s => h.Contains (s)).First ());
		_wText.Text = $"{view.Frame.Width}";
		_hText.Text = $"{view.Frame.Height}";
	}

	void UpdateTitle (View view) => _hostPane.Title = $"{view.GetType ().Name} - {view.X}, {view.Y}, {view.Width}, {view.Height}";

	List<Type> GetAllViewClassesCollection ()
	{
		var types = new List<Type> ();
		foreach (var type in typeof (View).Assembly.GetTypes ()
						.Where (myType => myType.IsClass && !myType.IsAbstract && myType.IsPublic && myType.IsSubclassOf (typeof (View)))) {
			types.Add (type);
		}
		types.Add (typeof (View));
		return types;
	}

	// TODO: Add Command.Default handler (pop a message box?)
	View CreateClass (Type type)
	{
		// If we are to create a generic Type
		if (type.IsGenericType) {

			// For each of the <T> arguments
			var typeArguments = new List<Type> ();

			// use <object>
			foreach (var arg in type.GetGenericArguments ()) {
				typeArguments.Add (typeof (object));
			}

			// And change what type we are instantiating from MyClass<T> to MyClass<object>
			type = type.MakeGenericType (typeArguments.ToArray ());
		}
		// Instantiate view
		var view = (View)Activator.CreateInstance (type);

		// Set the colorscheme to make it stand out if is null by default
		if (view.ColorScheme == null) {
			view.ColorScheme = Colors.Base;
		}

		// If the view supports a Text property, set it so we have something to look at
		if (view.GetType ().GetProperty ("Text") != null) {
			try {
				view.GetType ().GetProperty ("Text")?.GetSetMethod ()?.Invoke (view, new [] { "Test Text" });
			} catch (TargetInvocationException e) {
				MessageBox.ErrorQuery ("Exception", e.InnerException.Message, "Ok");
				view = null;
			}
		}

		// If the view supports a Title property, set it so we have something to look at
		if (view != null && view.GetType ().GetProperty ("Title") != null) {
			if (view.GetType ().GetProperty ("Title").PropertyType == typeof (string)) {
				view?.GetType ().GetProperty ("Title")?.GetSetMethod ()?.Invoke (view, new [] { "Test Title" });
			} else {
				view?.GetType ().GetProperty ("Title")?.GetSetMethod ()?.Invoke (view, new [] { "Test Title" });
			}
		}

		// If the view supports a Source property, set it so we have something to look at
		if (view != null && view.GetType ().GetProperty ("Source") != null && view.GetType ().GetProperty ("Source").PropertyType == typeof (IListDataSource)) {
			var source = new ListWrapper (new List<string> () { "Test Text #1", "Test Text #2", "Test Text #3" });
			view?.GetType ().GetProperty ("Source")?.GetSetMethod ()?.Invoke (view, new [] { source });
		}

		// Set Settings
		_computedCheckBox.Checked = view.LayoutStyle == LayoutStyle.Computed;

		view.Initialized += View_Initialized;

		// Add
		_hostPane.Add (view);
		_hostPane.SetNeedsDisplay ();

		return view;
	}

	void View_Initialized (object sender, EventArgs e)
	{
		var view = sender as View;

		//view.X = Pos.Center ();
		//view.Y = Pos.Center ();
		if (view.Width == null || view.Frame.Width == 0) {
			view.Width = Dim.Fill();
		}
		if (view.Height == null || view.Frame.Height == 0) {
			view.Height = Dim.Fill();
		}
		UpdateSettings (view);
		UpdateTitle (view);
	}

	void LayoutCompleteHandler (object sender, LayoutEventArgs args)
	{
		UpdateSettings (_curView);
		UpdateTitle (_curView);
	}

	void Quit () => Application.RequestStop ();
}