feature: update blame data when clicking/navigating commits (#1408)

* initial work on allowing navigation by clicking on commits in the blame window
* cleanup

src/ViewModels/Blame.cs

@@ -12,8 +12,8 @@ namespace SourceGit.ViewModels
     {
         public string Title
         {
-            get;
+            get => _title;
-            private set;
+            private set => SetProperty(ref _title, value);
         }
 
         public bool IsBinary
@@ -21,6 +21,15 @@ namespace SourceGit.ViewModels
             get => _data != null && _data.IsBinary;
         }
 
+        public bool CanMoveBack
+        {
+            get => _shaHistoryIndex > 0 && _shaHistory.Count > 1;
+        }
+        public bool CanMoveForward
+        {
+            get => _shaHistoryIndex < _shaHistory.Count - 1;
+        }
+
         public Models.BlameData Data
         {
             get => _data;
@@ -30,20 +39,60 @@ namespace SourceGit.ViewModels
         public Blame(string repo, string file, string revision)
         {
             _repo = repo;
+            _file = file;
+
+            SetBlameData($"{revision.AsSpan(0, 10)}", true);
+        }
+
+        private void SetBlameData(string commitSHA, bool resetHistoryForward)
+        {
+            Title = $"{_file} @ {commitSHA}";
 
-            Title = $"{file} @ {revision.AsSpan(0, 10)}";
             Task.Run(() =>
             {
-                var result = new Commands.Blame(repo, file, revision).Result();
+                var result = new Commands.Blame(_repo, _file, commitSHA).Result();
                 Dispatcher.UIThread.Invoke(() =>
                 {
                     Data = result;
                     OnPropertyChanged(nameof(IsBinary));
                 });
             });
+
+            if (resetHistoryForward)
+            {
+                if (_shaHistoryIndex < _shaHistory.Count - 1)
+                    _shaHistory.RemoveRange(_shaHistoryIndex + 1, _shaHistory.Count - _shaHistoryIndex - 1);
+
+                if (_shaHistory.Count == 0 || _shaHistory[_shaHistoryIndex] != commitSHA)
+                {
+                    _shaHistory.Add(commitSHA);
+                    _shaHistoryIndex = _shaHistory.Count - 1;
+                }
+            }
+
+            OnPropertyChanged(nameof(CanMoveBack));
+            OnPropertyChanged(nameof(CanMoveForward));
         }
 
-        public void NavigateToCommit(string commitSHA)
+        public void Back()
+        {
+            --_shaHistoryIndex;
+            if (_shaHistoryIndex < 0)
+                _shaHistoryIndex = 0;
+
+            NavigateToCommit(_shaHistory[_shaHistoryIndex], false);
+        }
+
+        public void Forward()
+        {
+            ++_shaHistoryIndex;
+            if (_shaHistoryIndex >= _shaHistory.Count)
+                _shaHistoryIndex = _shaHistory.Count - 1;
+
+            NavigateToCommit(_shaHistory[_shaHistoryIndex], false);
+        }
+
+        public void NavigateToCommit(string commitSHA, bool resetHistoryForward)
         {
             var launcher = App.GetLauncher();
             if (launcher == null)
@@ -54,6 +103,7 @@ namespace SourceGit.ViewModels
                 if (page.Data is Repository repo && repo.FullPath.Equals(_repo))
                 {
                     repo.NavigateToCommit(commitSHA);
+                    SetBlameData(commitSHA, resetHistoryForward);
                     break;
                 }
             }
@@ -69,7 +119,11 @@ namespace SourceGit.ViewModels
             return msg;
         }
 
-        private readonly string _repo;
+        private string _repo;
+        private string _file;
+        private string _title;
+        private int _shaHistoryIndex = 0;
+        private List<string> _shaHistory = [];
         private Models.BlameData _data = null;
         private Dictionary<string, string> _commitMessages = new Dictionary<string, string>();
     }

src/Views/Blame.axaml

@@ -42,8 +42,24 @@
     </Grid>
 
     <!-- File -->
-    <Border Grid.Row="1" Padding="8,0">
+    <Border Grid.Row="1" Padding="8,0" >
-      <TextBlock Text="{Binding Title}" VerticalAlignment="Center"/>
+      <Grid>
+        <TextBlock Text="{Binding Title}" VerticalAlignment="Center"/>
+        <StackPanel HorizontalAlignment="Right" VerticalAlignment="Center" Orientation="Horizontal">
+          <Button Classes="icon_button"
+                  IsEnabled="{Binding CanMoveBack}"
+                  Width="28"
+                  Click="HistoryBack">
+            <Path Width="12" Height="12" Stretch="Uniform" Data="{StaticResource Icons.TriangleLeft}"/>
+          </Button>
+          <Button Classes="icon_button"
+                  IsEnabled="{Binding CanMoveForward}"
+                  Width="28"
+                  Click="HistoryForward">
+            <Path Width="12" Height="12" Stretch="Uniform" Data="{StaticResource Icons.TriangleRight}"/>
+          </Button>
+        </StackPanel>
+      </Grid>
     </Border>
 
     <!-- Body -->

src/Views/Blame.axaml.cs

@@ -225,7 +225,7 @@ namespace SourceGit.Views
                         {
                             if (DataContext is ViewModels.Blame blame)
                             {
-                                blame.NavigateToCommit(info.CommitSHA);
+                                blame.NavigateToCommit(info.CommitSHA, true);
                             }
 
                             e.Handled = true;
@@ -433,6 +433,8 @@ namespace SourceGit.Views
         public Blame()
         {
             InitializeComponent();
+
+            AddHandler(PointerReleasedEvent, MouseUpHandler, handledEventsToo: true);
         }
 
         protected override void OnClosed(EventArgs e)
@@ -440,5 +442,32 @@ namespace SourceGit.Views
             base.OnClosed(e);
             GC.Collect();
         }
+
+        private void HistoryBack(object _, RoutedEventArgs e)
+        {
+            if (DataContext is ViewModels.Blame blame)
+            {
+                blame.Back();
+            }
+        }
+        private void HistoryForward(object _, RoutedEventArgs e)
+        {
+            if (DataContext is ViewModels.Blame blame)
+            {
+                blame.Forward();
+            }
+        }
+
+        private void MouseUpHandler(object sender, PointerReleasedEventArgs e)
+        {
+            if (e.InitialPressMouseButton == MouseButton.XButton1)
+            {
+                HistoryBack(null, null);
+            }
+            else if (e.InitialPressMouseButton == MouseButton.XButton2)
+            {
+                HistoryForward(null, null);
+            }
+        }
     }
 }