update code style and make file-loading async

QuickLook.Plugin/QuickLook.Plugin.TextViewer/TextViewerPanel.cs

@@ -0,0 +1,140 @@
+// Copyright © 2017 Paddy Xu
+// 
+// This file is part of QuickLook program.
+// 
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// 
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+using System;
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Input;
+using System.Windows.Media;
+using System.Windows.Threading;
+using ICSharpCode.AvalonEdit;
+using ICSharpCode.AvalonEdit.Document;
+using ICSharpCode.AvalonEdit.Highlighting;
+using QuickLook.Common.Helpers;
+using QuickLook.Common.Plugin;
+using UtfUnknown;
+
+namespace QuickLook.Plugin.TextViewer
+{
+    public class TextViewerPanel : TextEditor, IDisposable
+    {
+        private readonly ContextObject _context;
+        private bool _disposed;
+
+        public TextViewerPanel(string path, ContextObject context)
+        {
+            _context = context;
+
+            Background = Brushes.Transparent;
+            FontSize = 14;
+            ShowLineNumbers = true;
+            WordWrap = true;
+            IsReadOnly = true;
+            IsManipulationEnabled = true;
+
+            ManipulationInertiaStarting += Viewer_ManipulationInertiaStarting;
+            ManipulationStarting += Viewer_ManipulationStarting;
+            ManipulationDelta += Viewer_ManipulationDelta;
+
+            PreviewMouseWheel += Viewer_MouseWheel;
+
+            FontFamily = new FontFamily(TranslationHelper.Get("Editor_FontFamily"));
+
+            LoadFileAsync(path);
+        }
+
+        public void Dispose()
+        {
+            _disposed = true;
+        }
+
+        private void Viewer_ManipulationInertiaStarting(object sender, ManipulationInertiaStartingEventArgs e)
+        {
+            e.TranslationBehavior = new InertiaTranslationBehavior
+            {
+                InitialVelocity = e.InitialVelocities.LinearVelocity,
+                DesiredDeceleration = 10.0 * 96.0 / (1000.0 * 1000.0)
+            };
+        }
+
+        private void Viewer_MouseWheel(object sender, MouseWheelEventArgs e)
+        {
+            e.Handled = true;
+
+            ScrollToVerticalOffset(VerticalOffset - e.Delta);
+        }
+
+        private void Viewer_ManipulationDelta(object sender, ManipulationDeltaEventArgs e)
+        {
+            e.Handled = true;
+
+            var delta = e.DeltaManipulation;
+            ScrollToVerticalOffset(VerticalOffset - delta.Translation.Y);
+        }
+
+        private void Viewer_ManipulationStarting(object sender, ManipulationStartingEventArgs e)
+        {
+            e.Mode = ManipulationModes.Translate;
+        }
+
+        private void LoadFileAsync(string path)
+        {
+            Task.Run(() =>
+            {
+                const int maxLength = 50 * 1024 * 1024;
+                var buffer = new MemoryStream();
+
+                using (var s = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
+                {
+                    while (s.Position < s.Length && buffer.Length < maxLength)
+                    {
+                        if (_disposed)
+                            break;
+
+                        var lb = new byte[8192];
+                        var count = s.Read(lb, 0, lb.Length);
+                        buffer.Write(lb, 0, count);
+                    }
+                }
+
+                if (_disposed)
+                    return;
+
+                _context.Title += " (0 ~ 50MB)";
+
+                var encoding = CharsetDetector.DetectFromBytes(buffer.GetBuffer()).Detected?.Encoding ??
+                               Encoding.Default;
+
+                var doc = new TextDocument(encoding.GetString(buffer.GetBuffer()));
+                doc.SetOwnerThread(Dispatcher.Thread);
+
+                if (_disposed)
+                    return;
+
+                Dispatcher.BeginInvoke(new Action(() =>
+                {
+                    Encoding = encoding;
+                    SyntaxHighlighting = HighlightingManager.Instance.GetDefinitionByExtension(Path.GetExtension(path));
+                    Document = doc;
+
+                    _context.IsBusy = false;
+                }), DispatcherPriority.Render);
+            });
+        }
+    }
+}