feature: double tap specific branch (#1416)

* feature: double tap specific branch
* exactly match behavior of left sidebar

src/ViewModels/Histories.cs

@@ -209,8 +209,47 @@ namespace SourceGit.ViewModels
             }
         }
 
-        public void DoubleTapped(Models.Commit commit)
+        public void DoubleTapped(Models.Commit commit, Models.Decorator decorator = null)
         {
+            if (decorator != null)
+            {
+                if (decorator.Type == Models.DecoratorType.LocalBranchHead)
+                {
+                    var b = _repo.Branches.Find(x => x.FriendlyName == decorator.Name);
+                    if (b != null)
+                    {
+                        _repo.CheckoutBranch(b);
+                        return;
+                    }
+                }
+                else if (decorator.Type == Models.DecoratorType.RemoteBranchHead)
+                {
+                    var remoteBranch = _repo.Branches.Find(x => x.FriendlyName == decorator.Name);
+                    if (remoteBranch != null)
+                    {
+                        var localBranch = _repo.Branches.Find(x => x.IsLocal && x.Upstream == remoteBranch.FullName);
+                        if (localBranch != null)
+                        {
+                            if (localBranch.IsCurrent)
+                                return;
+                            if (localBranch.TrackStatus.Ahead.Count > 0)
+                            {
+                                if (_repo.CanCreatePopup())
+                                    _repo.ShowPopup(new CreateBranch(_repo, remoteBranch));
+                            }
+                            else if (localBranch.TrackStatus.Behind.Count > 0)
+                            {
+                                if (_repo.CanCreatePopup())
+                                    _repo.ShowPopup(new CheckoutAndFastForward(_repo, localBranch, remoteBranch));
+                            }
+                            else
+                                _repo.CheckoutBranch(localBranch);
+                            return;
+                        }
+                    }
+                }
+            }
+
             if (commit == null || commit.IsCurrentHead)
                 return;
 

src/Views/CommitRefsPresenter.cs

@@ -156,6 +156,22 @@ namespace SourceGit.Views
             InvalidateMeasure();
         }
 
+        public Models.Decorator DecoratorAt(Point point)
+        {
+            if (DataContext is not Models.Commit commit)
+                return null;
+            
+            var x = 0.0;
+            for (var i = 0; i < _items.Count; i++)
+            {
+                x += _items[i].Width + 4;
+                if (point.X < x)
+                    return commit.Decorators[i];
+            }
+            
+            return null;
+        }
+        
         protected override Size MeasureOverride(Size availableSize)
         {
             _items.Clear();

src/Views/Histories.axaml.cs

@@ -173,10 +173,14 @@ namespace SourceGit.Views
         {
             if (DataContext is ViewModels.Histories histories && sender is ListBox { SelectedItems.Count: 1 })
             {
+                Models.Decorator decorator = null;
+                if (e.Source is CommitRefsPresenter crp)
+                    decorator = crp.DecoratorAt(e.GetPosition(crp));
+
                 var source = e.Source as Control;
                 var item = source.FindAncestorOfType<ListBoxItem>();
                 if (item is { DataContext: Models.Commit commit })
-                    histories.DoubleTapped(commit);
+                    histories.DoubleTapped(commit, decorator);
             }
             e.Handled = true;
         }