add sln picker

src/SharpIDE.Godot/IdeWindow.cs

@@ -0,0 +1,63 @@
+using Ardalis.GuardClauses;
+using Godot;
+using Microsoft.Build.Locator;
+using Microsoft.Extensions.Hosting;
+using SharpIDE.Godot.Features.SlnPicker;
+
+namespace SharpIDE.Godot;
+
+/// <summary>
+/// Used to hold either the main IDE scene or the solution picker scene
+/// </summary>
+public partial class IdeWindow : Control
+{
+    private readonly PackedScene _solutionPickerScene = ResourceLoader.Load<PackedScene>("res://Features/SlnPicker/SlnPicker.tscn");
+    private readonly PackedScene _ideRootScene = ResourceLoader.Load<PackedScene>("res://IdeRoot.tscn");
+
+    private IdeRoot? _ideRoot;
+    private SlnPicker? _slnPicker;
+
+    public override void _Ready()
+    {
+        MSBuildLocator.RegisterDefaults();
+        GodotServiceDefaults.AddServiceDefaults();
+        
+        PickSolution();
+    }
+
+    public void PickSolution()
+    {
+        if (_slnPicker is not null) throw new InvalidOperationException("Solution picker is already active");
+        _slnPicker = _solutionPickerScene.Instantiate<SlnPicker>();
+        AddChild(_slnPicker);
+        _ = Task.GodotRun(async () =>
+        {
+            var slnPathTask = _slnPicker.GetSelectedSolutionPath();
+            var ideRoot = _ideRootScene.Instantiate<IdeRoot>();
+            ideRoot.IdeWindow = this;
+            var slnPath = await slnPathTask;
+            if (slnPath is null)
+            {
+                ideRoot.QueueFree();
+                _slnPicker.QueueFree();
+                _slnPicker = null;
+                return;
+            }
+            ideRoot.SetSlnFilePath(slnPath);
+            
+            await this.InvokeAsync(() =>
+            {
+                RemoveChild(_slnPicker);
+                _slnPicker.QueueFree();
+                _slnPicker = null;
+                if (_ideRoot is not null)
+                {
+                    RemoveChild(_ideRoot);
+                    _ideRoot.QueueFree();
+                }
+                _ideRoot = ideRoot;
+                AddChild(ideRoot);
+            });
+        });
+    }
+}