code_review: PR #1408

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

src/ViewModels/Blame.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Threading;
 using System.Threading.Tasks;
 
 using Avalonia.Threading;
@@ -10,10 +11,25 @@ namespace SourceGit.ViewModels
 {
     public class Blame : ObservableObject
     {
-        public string Title
+        public string FilePath
         {
-            get => _title;
-            private set => SetProperty(ref _title, value);
+            get;
+        }
+
+        public Models.Commit Revision
+        {
+            get => _revision;
+            private set => SetProperty(ref _revision, value);
+        }
+
+        public Models.BlameData Data
+        {
+            get => _data;
+            private set
+            {
+                if (SetProperty(ref _data, value))
+                    OnPropertyChanged(nameof(IsBinary));
+            }
         }
 
         public bool IsBinary
@@ -21,92 +37,27 @@ namespace SourceGit.ViewModels
             get => _data != null && _data.IsBinary;
         }
 
-        public bool CanMoveBack
+        public bool CanBack
         {
-            get => _shaHistoryIndex > 0 && _shaHistory.Count > 1;
-        }
-        public bool CanMoveForward
-        {
-            get => _shaHistoryIndex < _shaHistory.Count - 1;
+            get => _navigationActiveIndex > 0;
         }
 
-        public Models.BlameData Data
+        public bool CanForward
         {
-            get => _data;
-            private set => SetProperty(ref _data, value);
+            get => _navigationActiveIndex < _navigationHistory.Count - 1;
         }
 
-        public Blame(string repo, string file, string revision)
+        public Blame(string repo, string file, Models.Commit commit)
         {
+            var sha = commit.SHA.Substring(0, 10);
+
+            FilePath = file;
+            Revision = commit;
+
             _repo = repo;
-            _file = file;
-
-            SetBlameData($"{revision.AsSpan(0, 10)}", true);
-        }
-
-        private void SetBlameData(string commitSHA, bool resetHistoryForward)
-        {
-            Title = $"{_file} @ {commitSHA}";
-
-            Task.Run(() =>
-            {
-                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 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)
-                return;
-
-            foreach (var page in launcher.Pages)
-            {
-                if (page.Data is Repository repo && repo.FullPath.Equals(_repo))
-                {
-                    repo.NavigateToCommit(commitSHA);
-                    SetBlameData(commitSHA, resetHistoryForward);
-                    break;
-                }
-            }
+            _navigationHistory.Add(sha);
+            _commits.Add(sha, commit);
+            SetBlameData(sha);
         }
 
         public string GetCommitMessage(string sha)
@@ -119,12 +70,102 @@ namespace SourceGit.ViewModels
             return msg;
         }
 
+        public void Back()
+        {
+            if (_navigationActiveIndex <= 0)
+                return;
+
+            _navigationActiveIndex--;
+            OnPropertyChanged(nameof(CanBack));
+            OnPropertyChanged(nameof(CanForward));
+            NavigateToCommit(_navigationHistory[_navigationActiveIndex]);
+        }
+
+        public void Forward()
+        {
+            if (_navigationActiveIndex >= _navigationHistory.Count - 1)
+                return;
+
+            _navigationActiveIndex++;
+            OnPropertyChanged(nameof(CanBack));
+            OnPropertyChanged(nameof(CanForward));
+            NavigateToCommit(_navigationHistory[_navigationActiveIndex]);
+        }
+
+        public void NavigateToCommit(string commitSHA)
+        {
+            if (!_navigationHistory[_navigationActiveIndex].Equals(commitSHA, StringComparison.Ordinal))
+            {
+                _navigationHistory.Add(commitSHA);
+                _navigationActiveIndex = _navigationHistory.Count - 1;
+                OnPropertyChanged(nameof(CanBack));
+                OnPropertyChanged(nameof(CanForward));
+            }
+
+            if (!Revision.SHA.StartsWith(commitSHA, StringComparison.Ordinal))
+                SetBlameData(commitSHA);
+
+            if (App.GetLauncher() is { Pages: { } pages })
+            {
+                foreach (var page in pages)
+                {
+                    if (page.Data is Repository repo && repo.FullPath.Equals(_repo))
+                    {
+                        repo.NavigateToCommit(commitSHA);
+                        break;
+                    }
+                }
+            }            
+        }
+
+        private void SetBlameData(string commitSHA)
+        {
+            if (_cancellationSource is { IsCancellationRequested: false })
+                _cancellationSource.Cancel();
+
+            _cancellationSource = new CancellationTokenSource();
+            var token = _cancellationSource.Token;
+
+            if (_commits.TryGetValue(commitSHA, out var c))
+            {
+                Revision = c;
+            }
+            else
+            {
+                Task.Run(() =>
+                {
+                    var result = new Commands.QuerySingleCommit(_repo, commitSHA).Result();
+
+                    Dispatcher.UIThread.Invoke(() =>
+                    {
+                        if (!token.IsCancellationRequested)
+                        {
+                            _commits.Add(commitSHA, result);
+                            Revision = result ?? new Models.Commit() { SHA = commitSHA };
+                        }
+                    });
+                }, token);
+            }                
+
+            Task.Run(() =>
+            {
+                var result = new Commands.Blame(_repo, FilePath, commitSHA).Result();
+
+                Dispatcher.UIThread.Invoke(() =>
+                {
+                    if (!token.IsCancellationRequested)
+                        Data = result;
+                });
+            }, token);
+        }
+
         private string _repo;
-        private string _file;
-        private string _title;
-        private int _shaHistoryIndex = 0;
-        private List<string> _shaHistory = [];
+        private Models.Commit _revision;
+        private CancellationTokenSource _cancellationSource = null;
+        private int _navigationActiveIndex = 0;
+        private List<string> _navigationHistory = [];
         private Models.BlameData _data = null;
-        private Dictionary<string, string> _commitMessages = new Dictionary<string, string>();
+        private Dictionary<string, Models.Commit> _commits = new();
+        private Dictionary<string, string> _commitMessages = new();
     }
 }

src/ViewModels/CommitDetail.cs

@@ -313,7 +313,7 @@ namespace SourceGit.ViewModels
             blame.IsEnabled = change.Index != Models.ChangeState.Deleted;
             blame.Click += (_, ev) =>
             {
-                App.ShowWindow(new Blame(_repo.FullPath, change.Path, _commit.SHA), false);
+                App.ShowWindow(new Blame(_repo.FullPath, change.Path, _commit), false);
                 ev.Handled = true;
             };
 
@@ -481,7 +481,7 @@ namespace SourceGit.ViewModels
             blame.IsEnabled = file.Type == Models.ObjectType.Blob;
             blame.Click += (_, ev) =>
             {
-                App.ShowWindow(new Blame(_repo.FullPath, file.Path, _commit.SHA), false);
+                App.ShowWindow(new Blame(_repo.FullPath, file.Path, _commit), false);
                 ev.Handled = true;
             };
 

src/Views/Blame.axaml

@@ -4,6 +4,7 @@
                     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                     xmlns:vm="using:SourceGit.ViewModels"
                     xmlns:v="using:SourceGit.Views"
+                    xmlns:c="using:SourceGit.Converters"
                     mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
                     x:Class="SourceGit.Views.Blame"
                     x:DataType="vm:Blame"
@@ -43,22 +44,44 @@
 
     <!-- File -->
     <Border Grid.Row="1" Padding="8,0" >
-      <Grid>
-        <TextBlock Text="{Binding Title}" VerticalAlignment="Center"/>
-        <StackPanel HorizontalAlignment="Right" VerticalAlignment="Center" Orientation="Horizontal">
-          <Button Classes="icon_button"
-                  IsEnabled="{Binding CanMoveBack}"
+      <Grid ColumnDefinitions="Auto,*,Auto,Auto,400">
+        <Path Grid.Column="0"
+              Width="14" Height="14"
+              Data="{StaticResource Icons.File}"/>
+        
+        <TextBlock Grid.Column="1"
+                   Margin="4,0,0,0"
+                   VerticalAlignment="Center"
+                   Text="{Binding FilePath, Mode=OneWay}"/>
+
+        <Button Grid.Column="2"
+                Classes="icon_button"
+                IsEnabled="{Binding CanBack}"
                 Width="28"
-                  Click="HistoryBack">
-            <Path Width="12" Height="12" Stretch="Uniform" Data="{StaticResource Icons.TriangleLeft}"/>
+                Command="{Binding Back}">
+          <Path Width="12" Height="12" Data="{StaticResource Icons.TriangleLeft}"/>
         </Button>
-          <Button Classes="icon_button"
-                  IsEnabled="{Binding CanMoveForward}"
+        
+        <Button Grid.Column="3"
+                Classes="icon_button"
+                IsEnabled="{Binding CanForward}"
                 Width="28"
-                  Click="HistoryForward">
-            <Path Width="12" Height="12" Stretch="Uniform" Data="{StaticResource Icons.TriangleRight}"/>
+                Command="{Binding Forward}">
+          <Path Width="12" Height="12" Data="{StaticResource Icons.TriangleRight}"/>
         </Button>
-        </StackPanel>
+
+        <Border Grid.Column="4" Background="#40000000" CornerRadius="3" Padding="4,0" Margin="0,2">
+          <Grid ColumnDefinitions="Auto,*">
+            <TextBlock Grid.Column="0"
+                       FontWeight="Bold"
+                       Margin="0,0,6,0"
+                       Text="{Binding Revision.SHA, Converter={x:Static c:StringConverters.ToShortSHA}, Mode=OneWay}"/>
+
+            <TextBlock Grid.Column="2"
+                       Text="{Binding Revision.Subject}"
+                       TextTrimming="CharacterEllipsis"/>
+          </Grid>          
+        </Border>
       </Grid>
     </Border>
 

src/Views/Blame.axaml.cs

@@ -224,9 +224,7 @@ namespace SourceGit.Views
                         if (rect.Contains(pos))
                         {
                             if (DataContext is ViewModels.Blame blame)
-                            {
-                                blame.NavigateToCommit(info.CommitSHA, true);
-                            }
+                                blame.NavigateToCommit(info.CommitSHA);
 
                             e.Handled = true;
                             break;
@@ -433,8 +431,6 @@ namespace SourceGit.Views
         public Blame()
         {
             InitializeComponent();
-
-            AddHandler(PointerReleasedEvent, MouseUpHandler, handledEventsToo: true);
         }
 
         protected override void OnClosed(EventArgs e)
@@ -443,30 +439,22 @@ namespace SourceGit.Views
             GC.Collect();
         }
 
-        private void HistoryBack(object _, RoutedEventArgs e)
+        protected override void OnPointerReleased(PointerReleasedEventArgs e)
         {
-            if (DataContext is ViewModels.Blame blame)
-            {
-                blame.Back();
-            }
-        }
-        private void HistoryForward(object _, RoutedEventArgs e)
-        {
-            if (DataContext is ViewModels.Blame blame)
-            {
-                blame.Forward();
-            }
-        }
+            base.OnPointerReleased(e);
 
-        private void MouseUpHandler(object sender, PointerReleasedEventArgs e)
+            if (!e.Handled && DataContext is ViewModels.Blame blame)
             {
                 if (e.InitialPressMouseButton == MouseButton.XButton1)
                 {
-                HistoryBack(null, null);
+                    blame.Back();
+                    e.Handled = true;
                 }
                 else if (e.InitialPressMouseButton == MouseButton.XButton2)
                 {
-                HistoryForward(null, null);
+                    blame.Forward();
+                    e.Handled = true;
+                }
             }
         }
     }