created ChangeWatcher API: allows display of changes from different data sources (changes while file is opened, Git/SVN diff, etc.)

src/AddIns/DisplayBindings/AvalonEdit.AddIn/Src/ChangeMarkerMargin.cs

@@ -8,6 +8,7 @@ using System.Windows;
 using System.Windows.Media;
 using ICSharpCode.AvalonEdit.Document;
 using ICSharpCode.AvalonEdit.Editing;
+using ICSharpCode.AvalonEdit.Folding;
 using ICSharpCode.AvalonEdit.Rendering;
 using ICSharpCode.SharpDevelop;
 using ICSharpCode.SharpDevelop.Editor;
@@ -17,19 +18,19 @@ namespace ICSharpCode.AvalonEdit.AddIn
 	/// <summary>
 	/// Description of ChangeMarkerMargin.
 	/// </summary>
-	public class ChangeMarkerMargin : AbstractMargin, ILineTracker, IDisposable
+	public class ChangeMarkerMargin : AbstractMargin, IDisposable
 	{
-		WeakLineTracker lineTracker;
-		List<DocumentLine> changedLines;
-		List<DocumentLine> lastSavedChangedLines;
-		bool changed;
-		OpenedFile openedFile;
+		IChangeWatcher changeWatcher;
 		
-		public ChangeMarkerMargin()
-		{
-			changedLines = new List<DocumentLine>();
-			lastSavedChangedLines = new List<DocumentLine>();
-			changed = false;
+		public IChangeWatcher ChangeWatcher {
+			get { return changeWatcher; }
+			set {
+				if (changeWatcher != null)
+					changeWatcher.ChangeOccured -= ChangeOccured;
+				changeWatcher = value;
+				if (changeWatcher != null)
+					changeWatcher.ChangeOccured += ChangeOccured;
+			}
 		}
 		
 		protected override void OnRender(DrawingContext drawingContext)
@@ -39,73 +40,191 @@ namespace ICSharpCode.AvalonEdit.AddIn
 			
 			if (textView != null && textView.VisualLinesValid) {
 				ITextEditor editor = textView.Services.GetService(typeof(ITextEditor)) as ITextEditor;
-				openedFile = FileService.GetOpenedFile(editor.FileName);
-				openedFile.IsDirtyChanged += IsDirtyChanged;
-				textView.ScrollOffsetChanged += ScrollOffsetChanged;
-				
-				if (lineTracker == null)
-					lineTracker = WeakLineTracker.Register(textView.Document, this);
 				
 				foreach (VisualLine line in textView.VisualLines) {
 					Rect rect = new Rect(0, line.VisualTop - textView.ScrollOffset.Y, renderSize.Width, line.Height);
-					if (lastSavedChangedLines.Contains(line.FirstDocumentLine))
-						drawingContext.DrawRectangle(Brushes.LightGreen, null, rect);
-					else if (changedLines.Contains(line.FirstDocumentLine))
-						drawingContext.DrawRectangle(Brushes.Yellow, null, rect);
+					
+					ChangeType type = changeWatcher.GetChange(editor.Document.GetLine(line.FirstDocumentLine.LineNumber));
+					
+					switch (type) {
+						case ChangeType.None:
+							break;
+						case ChangeType.Added:
+						case ChangeType.Saved:
+							drawingContext.DrawRectangle(Brushes.LightGreen, null, rect);
+							break;
+						case ChangeType.Deleted:
+							// TODO : implement
+							break;
+						case ChangeType.Modified:
+							drawingContext.DrawRectangle(Brushes.Blue, null, rect);
+							break;
+						case ChangeType.Unsaved:
+							drawingContext.DrawRectangle(Brushes.Yellow, null, rect);
+							break;
+						default:
+							throw new Exception("Invalid value for ChangeType");
+					}
 				}
 			}
 		}
+		
+		protected override void OnTextViewChanged(TextView oldTextView, TextView newTextView)
+		{
+			if (ChangeWatcher == null)
+				ChangeWatcher = new LocalChangeWatcher();
+			
+			if (oldTextView != null) {
+				oldTextView.VisualLinesChanged -= VisualLinesChanged;
+				oldTextView.ScrollOffsetChanged -= ScrollOffsetChanged;
+			}
+			
+			if (newTextView != null) {
+				newTextView.VisualLinesChanged += VisualLinesChanged;
+				newTextView.ScrollOffsetChanged += ScrollOffsetChanged;
+				
+				ITextEditor editor = newTextView.Services.GetService(typeof(ITextEditor)) as ITextEditor;
+				changeWatcher.UpdateTextEditor(editor);
+			}
+		}
+		
+		protected override void OnDocumentChanged(TextDocument oldDocument, TextDocument newDocument)
+		{
+			if (ChangeWatcher == null)
+				ChangeWatcher = new LocalChangeWatcher();
+			
+			ITextEditor editor = TextView.Services.GetService(typeof(ITextEditor)) as ITextEditor;
+			changeWatcher.UpdateTextEditor(editor);
+		}
 
+		void VisualLinesChanged(object sender, EventArgs e)
+		{
+			InvalidateVisual();
+		}
+		
 		void ScrollOffsetChanged(object sender, EventArgs e)
 		{
 			InvalidateVisual();
 		}
-
+		
+		void ChangeOccured(object sender, EventArgs e)
+		{
+			InvalidateVisual();
+		}
+		
+		protected override Size MeasureOverride(Size availableSize)
+		{
+			return new Size(5, 0);
+		}
+		
+		bool disposed = false;
+		
+		public void Dispose()
+		{
+			if (!disposed) {
+				OnTextViewChanged(TextView, null);
+				changeWatcher.Dispose();
+				ChangeWatcher = null;
+				disposed = true;
+			}
+		}
+	}
+	
+	public interface IChangeWatcher : IDisposable
+	{
+		event EventHandler ChangeOccured;
+		ChangeType GetChange(IDocumentLine line);
+		void UpdateTextEditor(ITextEditor editor);
+	}
+	
+	public enum ChangeType : int
+	{
+		None       = 0x0000,
+		Added      = 0x0001,
+		Deleted    = 0x0002,
+		Modified   = 0x0004,
+		/// <summary>
+		/// Only to be used by LocalChangeWatcher. States if a change is unsaved or not.
+		/// </summary>
+		Saved      = 0x0008,
+		/// <summary>
+		/// Only to be used by LocalChangeWatcher. States if a change is unsaved or not.
+		/// </summary>
+		Unsaved    = 0x0016
+	}
+	
+	public class LocalChangeWatcher : IChangeWatcher, ILineTracker
+	{
+		WeakLineTracker lineTracker;
+		List<DocumentLine> changedLines;
+		List<DocumentLine> lastSavedChangedLines;
+		bool changed;
+		OpenedFile openedFile;
+		TextView textView;
+		ITextEditor editor;
+		
+		public event EventHandler ChangeOccured;
+		
+		protected void OnChangeOccured(EventArgs e)
+		{
+			if (ChangeOccured != null) {
+				ChangeOccured(this, e);
+			}
+		}
+		
+		public ChangeType GetChange(IDocumentLine line)
+		{
+			if (openedFile == null && editor.FileName != null) {
+				openedFile = FileService.GetOpenedFile(editor.FileName);
+				openedFile.IsDirtyChanged += IsDirtyChanged;
+			}
+			
+			DocumentLine documentLine = textView.Document.GetLineByNumber(line.LineNumber);
+			
+			if (lastSavedChangedLines.Contains(documentLine))
+				return ChangeType.Saved;
+			if (changedLines.Contains(documentLine))
+				return ChangeType.Unsaved;
+			
+			return ChangeType.None;
+		}
+		
 		void IsDirtyChanged(object sender, EventArgs e)
 		{
 			if (changed && !openedFile.IsDirty) {
 				lastSavedChangedLines = lastSavedChangedLines.Concat(changedLines).Distinct().ToList();
 				changedLines.Clear();
 				changed = false;
-				InvalidateVisual();
+				OnChangeOccured(EventArgs.Empty);
 			}
 		}
 		
-		protected override Size MeasureOverride(Size availableSize)
-		{
-			return new Size(5, 0);
-		}
-		
-		public void BeforeRemoveLine(DocumentLine line)
+		void ILineTracker.BeforeRemoveLine(DocumentLine line)
 		{
 			changedLines.Remove(line);
 			lastSavedChangedLines.Remove(line);
 			changed = true;
-			InvalidateVisual();
 		}
 		
-		public void SetLineLength(DocumentLine line, int newTotalLength)
+		void ILineTracker.SetLineLength(DocumentLine line, int newTotalLength)
 		{
 			if (!changedLines.Contains(line))
 				changedLines.Add(line);
 			lastSavedChangedLines.Remove(line);
 			changed = true;
-			InvalidateVisual();
 		}
 		
-		public void LineInserted(DocumentLine insertionPos, DocumentLine newLine)
+		void ILineTracker.LineInserted(DocumentLine insertionPos, DocumentLine newLine)
 		{
 			if (!changedLines.Contains(insertionPos))
 				changedLines.Add(insertionPos);
 			lastSavedChangedLines.Remove(insertionPos);
 			changedLines.Add(newLine);
 			changed = true;
-			InvalidateVisual();
 		}
 		
-		public void RebuildDocument()
+		void ILineTracker.RebuildDocument()
 		{
-			InvalidateVisual();
 		}
 		
 		bool disposed = false;
@@ -115,8 +234,35 @@ namespace ICSharpCode.AvalonEdit.AddIn
 			if (!disposed) {
 				lineTracker.Deregister();
 				openedFile.IsDirtyChanged -= IsDirtyChanged;
+				FileService.FileCreated -= FileServiceFileCreated;
 				disposed = true;
 			}
 		}
+		
+		public void UpdateTextEditor(ITextEditor editor)
+		{
+			if (lineTracker != null)
+				lineTracker.Deregister();
+			if (openedFile != null)
+				openedFile.IsDirtyChanged -= IsDirtyChanged;
+			
+			if (editor == null)
+				throw new ArgumentNullException("editor");
+			
+			this.editor = editor;
+			this.textView = editor.GetService(typeof(TextView)) as TextView;
+			FileService.FileCreated += FileServiceFileCreated;
+			
+			lineTracker = WeakLineTracker.Register(textView.Document, this);
+			
+			changed = false;
+			changedLines = new List<DocumentLine>();
+			lastSavedChangedLines = new List<DocumentLine>();
+		}
+		
+		void FileServiceFileCreated(object sender, FileEventArgs e)
+		{
+			
+		}
 	}
 }