feature: auto-select and scroll to current local branch when clicking Navigate To HEAD button in toolbar (#1022)

Signed-off-by: leo <longshuang@msn.cn>

src/Views/BranchTree.axaml.cs

@@ -241,6 +241,47 @@ namespace SourceGit.Views
             InitializeComponent();
         }
 
+        public void Select(Models.Branch branch)
+        {
+            if (branch == null)
+                return;
+
+            _disableSelectionChangingEvent = true;
+
+            var treePath = new List<ViewModels.BranchTreeNode>();
+            FindTreePath(treePath, Nodes, branch.Name, 0);
+
+            if (treePath.Count == 0)
+            {
+                _disableSelectionChangingEvent = false;
+                return;
+            }
+
+            var oldRowCount = Rows.Count;
+            var rows = Rows;
+            for (var i = 0; i < treePath.Count - 1; i++)
+            {
+                var node = treePath[i];
+                if (!node.IsExpanded)
+                {
+                    node.IsExpanded = true;
+
+                    var idx = rows.IndexOf(node);
+                    var subtree = new List<ViewModels.BranchTreeNode>();
+                    MakeRows(subtree, node.Children, node.Depth + 1);
+                    rows.InsertRange(idx + 1, subtree);
+                }
+            }
+
+            var target = treePath[treePath.Count - 1];
+            BranchesPresenter.SelectedItem = target;
+            BranchesPresenter.ScrollIntoView(target);
+            _disableSelectionChangingEvent = false;
+
+            if (oldRowCount != rows.Count)
+                RaiseEvent(new RoutedEventArgs(RowsChangedEvent));
+        }
+
         public void UnselectAll()
         {
             BranchesPresenter.SelectedItem = null;
@@ -534,6 +575,23 @@ namespace SourceGit.Views
                 CollectBranchesInNode(outs, sub);
         }
 
+        private void FindTreePath(List<ViewModels.BranchTreeNode> outPath, List<ViewModels.BranchTreeNode> collection, string path, int start)
+        {
+            if (start >= path.Length - 1)
+                return;
+
+            var sepIdx = path.IndexOf('/', start);
+            var name = sepIdx < 0 ? path.Substring(start) : path.Substring(start, sepIdx - start);
+            foreach (var node in collection)
+            {
+                if (node.Name.Equals(name, StringComparison.Ordinal))
+                {
+                    outPath.Add(node);
+                    FindTreePath(outPath, node.Children, path, sepIdx + 1);
+                }
+            }
+        }
+
         private bool _disableSelectionChangingEvent = false;
     }
 }

src/Views/RepositoryToolbar.axaml.cs

@@ -157,6 +157,9 @@ namespace SourceGit.Views
         {
             if (DataContext is ViewModels.Repository { CurrentBranch: not null } repo)
             {
+                var repoView = TopLevel.GetTopLevel(this)?.FindDescendantOfType<Repository>(false);
+                repoView?.LocalBranchTree?.Select(repo.CurrentBranch);
+
                 repo.NavigateToCommit(repo.CurrentBranch.Head);
                 e.Handled = true;
             }