enhance: show commit full message tooltip when hover commit subject in FileHistories view (#1232)

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

src/ViewModels/FileHistories.cs

@@ -305,11 +305,23 @@ namespace SourceGit.ViewModels
             _repo.NavigateToCommit(commit.SHA);
         }
 
+        public string GetCommitFullMessage(Models.Commit commit)
+        {
+            var sha = commit.SHA;
+            if (_fullCommitMessages.TryGetValue(sha, out var msg))
+                return msg;
+
+            msg = new Commands.QueryCommitFullMessage(_repo.FullPath, sha).Result();
+            _fullCommitMessages[sha] = msg;
+            return msg;
+        }
+
         private readonly Repository _repo = null;
         private readonly string _file = null;
         private bool _isLoading = true;
         private bool _prevIsDiffMode = true;
         private List<Models.Commit> _commits = null;
+        private Dictionary<string, string> _fullCommitMessages = new Dictionary<string, string>();
         private object _viewContent = null;
     }
 }

src/Views/FileHistories.axaml

@@ -93,7 +93,12 @@
                   <TextBlock Grid.Column="3" Classes="primary" Text="{Binding AuthorTimeShortStr}" Foreground="{DynamicResource Brush.FG2}" HorizontalAlignment="Right"/>
                 </Grid>
 
-                <TextBlock Grid.Row="1" Classes="primary" Text="{Binding Subject}" VerticalAlignment="Bottom"/>
+                <TextBlock Grid.Row="1"
+                           Classes="primary"
+                           Text="{Binding Subject}"
+                           VerticalAlignment="Bottom"
+                           DataContextChanged="OnCommitSubjectDataContextChanged"
+                           PointerMoved="OnCommitSubjectPointerMoved"/>
               </Grid>
             </Border>
           </DataTemplate>

src/Views/FileHistories.axaml.cs

@@ -1,3 +1,5 @@
+using System;
+
 using Avalonia.Controls;
 using Avalonia.Input;
 using Avalonia.Interactivity;
@@ -57,5 +59,22 @@ namespace SourceGit.Views
                 e.Handled = true;
             }
         }
+
+        private void OnCommitSubjectDataContextChanged(object sender, EventArgs e)
+        {
+            if (sender is TextBlock textBlock)
+                ToolTip.SetTip(textBlock, null);
+        }
+
+        private void OnCommitSubjectPointerMoved(object sender, PointerEventArgs e)
+        {
+            if (sender is TextBlock { DataContext: Models.Commit commit } textBlock &&
+                DataContext is ViewModels.FileHistories vm)
+            {
+                var tooltip = ToolTip.GetTip(textBlock);
+                if (tooltip == null)
+                    ToolTip.SetTip(textBlock, vm.GetCommitFullMessage(commit));
+            }
+        }
     }
 }