fix(dock): migrate primary editor to DockLayout, add persistent sizing, and refactor DockLayout

src/Editor/Ghost.Editor/View/Controls/DockLayout.Rendering.cs

@@ -0,0 +1,170 @@
+using Ghost.Editor.Core.Controls.Internal.Docking;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using Microsoft.UI.Xaml.Data;
+using System.Diagnostics;
+
+namespace Ghost.Editor.View.Controls;
+
+public sealed partial class DockLayout
+{
+    private void RenderTree()
+    {
+        if (GetTemplateChild(PART_ROOT_GRID) is Grid rootGrid)
+        {
+            rootGrid.Children.Clear();
+            if (Root != null)
+            {
+                var ui = CreateUIForNode(Root);
+                rootGrid.Children.Add(ui);
+            }
+        }
+    }
+
+    private UIElement CreateUIForNode(DockNode node)
+    {
+        if (node is DockGroupNode groupNode)
+        {
+            return CreateGroupUI(groupNode);
+        }
+        else if (node is DockPanelNode panelNode)
+        {
+            return CreatePanelUI(panelNode);
+        }
+
+        throw new InvalidOperationException($"Unsupported node type: {node.GetType().Name}");
+    }
+
+    private UIElement CreateGroupUI(DockGroupNode groupNode)
+    {
+        var grid = new Grid();
+        bool isHorizontal = groupNode.Orientation == Orientation.Horizontal;
+        int childCount = groupNode.Children.Count;
+
+        for (int i = 0; i < childCount; i++)
+        {
+            var childNode = groupNode.Children[i];
+            var childUI = CreateUIForNode(childNode);
+
+            if (isHorizontal)
+            {
+                var width = (i < groupNode.Sizes.Count) ? groupNode.Sizes[i] : new GridLength(1, GridUnitType.Star);
+                var colDef = new ColumnDefinition
+                {
+                    Width = width,
+                    MinWidth = MIN_PANE_SIZE
+                };
+                grid.ColumnDefinitions.Add(colDef);
+                Grid.SetColumn((FrameworkElement)childUI, i * 2);
+            }
+            else
+            {
+                var height = (i < groupNode.Sizes.Count) ? groupNode.Sizes[i] : new GridLength(1, GridUnitType.Star);
+                var rowDef = new RowDefinition
+                {
+                    Height = height,
+                    MinHeight = MIN_PANE_SIZE
+                };
+                grid.RowDefinitions.Add(rowDef);
+                Grid.SetRow((FrameworkElement)childUI, i * 2);
+            }
+
+            grid.Children.Add(childUI);
+
+            // Add GridSplitter between children
+            if (i < childCount - 1)
+            {
+                if (isHorizontal)
+                {
+                    grid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });
+                    var splitter = new CommunityToolkit.WinUI.Controls.GridSplitter
+                    {
+                        Width = SPLITTER_THICKNESS,
+                        HorizontalAlignment = HorizontalAlignment.Center,
+                        ResizeDirection = CommunityToolkit.WinUI.Controls.GridSplitter.GridResizeDirection.Columns
+                    };
+                    Grid.SetColumn(splitter, (i * 2) + 1);
+                    grid.Children.Add(splitter);
+                }
+                else
+                {
+                    grid.RowDefinitions.Add(new RowDefinition { Height = GridLength.Auto });
+                    var splitter = new CommunityToolkit.WinUI.Controls.GridSplitter
+                    {
+                        Height = SPLITTER_THICKNESS,
+                        VerticalAlignment = VerticalAlignment.Center,
+                        ResizeDirection = CommunityToolkit.WinUI.Controls.GridSplitter.GridResizeDirection.Rows
+                    };
+                    Grid.SetRow(splitter, (i * 2) + 1);
+                    grid.Children.Add(splitter);
+                }
+            }
+        }
+
+        // Capture size changes to persist back to model
+        grid.SizeChanged += (s, e) => SyncSizesToModel(groupNode, grid);
+
+        return grid;
+    }
+
+    private void SyncSizesToModel(DockGroupNode groupNode, Grid grid)
+    {
+        bool isHorizontal = groupNode.Orientation == Orientation.Horizontal;
+        if (isHorizontal)
+        {
+            for (int i = 0; i < groupNode.Children.Count; i++)
+            {
+                if (i < groupNode.Sizes.Count && i * 2 < grid.ColumnDefinitions.Count)
+                {
+                    groupNode.Sizes[i] = grid.ColumnDefinitions[i * 2].Width;
+                }
+            }
+        }
+        else
+        {
+            for (int i = 0; i < groupNode.Children.Count; i++)
+            {
+                if (i < groupNode.Sizes.Count && i * 2 < grid.RowDefinitions.Count)
+                {
+                    groupNode.Sizes[i] = grid.RowDefinitions[i * 2].Height;
+                }
+            }
+        }
+    }
+
+    private UIElement CreatePanelUI(DockPanelNode panelNode)
+    {
+        var tabView = new Ghost.Editor.Controls.NavigationTabView
+        {
+            TabItemsSource = panelNode.Items,
+            HorizontalAlignment = HorizontalAlignment.Stretch,
+            VerticalAlignment = VerticalAlignment.Stretch,
+            CanDragTabs = true,
+            AllowDrop = true,
+            Tag = panelNode // Store reference to data node
+        };
+
+        // Bind selection state using TabView DPs
+        tabView.SetBinding(TabView.SelectedIndexProperty, new Binding
+        {
+            Source = panelNode,
+            Path = new PropertyPath(nameof(DockPanelNode.SelectedIndex)),
+            Mode = BindingMode.TwoWay
+        });
+
+        tabView.SetBinding(TabView.SelectedItemProperty, new Binding
+        {
+            Source = panelNode,
+            Path = new PropertyPath(nameof(DockPanelNode.SelectedItem)),
+            Mode = BindingMode.TwoWay
+        });
+
+        tabView.DragOver += TabView_DragOver;
+        tabView.DragLeave += TabView_DragLeave;
+        tabView.Drop += TabView_Drop;
+        tabView.TabDragStarting += TabView_TabDragStarting;
+        tabView.TabDroppedOutside += TabView_TabDroppedOutside;
+
+        return tabView;
+    }
+}