feature: double click on commit (#295)

* when commit is current branch head, do nothing
* when commit is head of some local branch which is not current, try to checkout this branch
* otherwise, ask user should checkout selected commit as deteched

src/ViewModels/Histories.cs

@@ -142,6 +142,28 @@ namespace SourceGit.ViewModels
             }
         }
 
+        public void DoubleTapped(Models.Commit commit)
+        {
+            if (commit == null || commit.IsCurrentHead)
+                return;
+
+            foreach (var d in commit.Decorators)
+            {
+                if (d.Type == Models.DecoratorType.LocalBranchHead)
+                {
+                    var b = _repo.Branches.Find(x => x.FriendlyName == d.Name);
+                    if (b != null)
+                    {
+                        _repo.CheckoutBranch(b);
+                        return;
+                    }
+                }
+            }
+
+            if (PopupHost.CanCreatePopup())
+                PopupHost.ShowPopup(new CheckoutCommit(_repo, commit));
+        }
+
         public ContextMenu MakeContextMenu(DataGrid datagrid)
         {
             if (datagrid.SelectedItems.Count != 1)

src/Views/Histories.axaml

@@ -29,7 +29,8 @@
                 VerticalScrollBarVisibility="Auto"
                 LayoutUpdated="OnCommitDataGridLayoutUpdated"
                 SelectionChanged="OnCommitDataGridSelectionChanged"
-                ContextRequested="OnCommitDataGridContextRequested">
+                ContextRequested="OnCommitDataGridContextRequested"
+                DoubleTapped="OnCommitDataGridDoubleTapped">
         <DataGrid.Styles>
           <Style Selector="DataGridColumnHeader">
             <Setter Property="MinHeight" Value="24"/>

src/Views/Histories.axaml.cs

@@ -3,6 +3,7 @@ using System;
 using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Controls.Primitives;
+using Avalonia.Input;
 using Avalonia.Interactivity;
 using Avalonia.Media;
 using Avalonia.Threading;
@@ -409,5 +410,14 @@ namespace SourceGit.Views
             }
             e.Handled = true;
         }
+
+        private void OnCommitDataGridDoubleTapped(object sender, TappedEventArgs e)
+        {
+            if (DataContext is ViewModels.Histories histories && sender is DataGrid datagrid && datagrid.SelectedItems is { Count: 1 } selectedItems)
+            {
+                histories.DoubleTapped(selectedItems[0] as Models.Commit);   
+            }
+            e.Handled = true;
+        }
     }
 }