implement basic SearchPanel in AvalonEdit

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Editing/TextAreaDefaultInputHandlers.cs

@@ -4,8 +4,8 @@
 using System;
 using System.Windows;
 using System.Windows.Input;
-
 using ICSharpCode.AvalonEdit.Document;
+using ICSharpCode.AvalonEdit.Search;
 
 namespace ICSharpCode.AvalonEdit.Editing
 {
@@ -40,6 +40,7 @@ namespace ICSharpCode.AvalonEdit.Editing
 			
 			this.CommandBindings.Add(new CommandBinding(ApplicationCommands.Undo, ExecuteUndo, CanExecuteUndo));
 			this.CommandBindings.Add(new CommandBinding(ApplicationCommands.Redo, ExecuteRedo, CanExecuteRedo));
+			this.CommandBindings.Add(new CommandBinding(ApplicationCommands.Find, ExecuteFind));
 		}
 		
 		internal static KeyBinding CreateFrozenKeyBinding(ICommand command, ModifierKeys modifiers, Key key)
@@ -105,5 +106,10 @@ namespace ICSharpCode.AvalonEdit.Editing
 			}
 		}
 		#endregion
+		
+		void ExecuteFind(object sender, ExecutedRoutedEventArgs e)
+		{
+			new SearchPanel(TextArea);
+		}
 	}
 }

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/ICSharpCode.AvalonEdit.csproj

@@ -290,6 +290,7 @@
     <Compile Include="Rendering\VisualYPosition.cs">
       <DependentUpon>VisualLine.cs</DependentUpon>
     </Compile>
+    <Compile Include="Search\SearchPanel.cs" />
     <Compile Include="Snippets\IActiveElement.cs" />
     <Compile Include="Snippets\SnippetAnchorElement.cs" />
     <Compile Include="Snippets\SnippetEventArgs.cs" />
@@ -412,4 +413,7 @@
   <ItemGroup>
     <EmbeddedResource Include="Highlighting\Resources\CSS-Mode.xshd" />
   </ItemGroup>
+  <ItemGroup>
+    <Folder Include="Search" />
+  </ItemGroup>
 </Project>

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Search/SearchPanel.cs

@@ -0,0 +1,143 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
+
+using System;
+using System.Linq;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
+using System.Windows.Media;
+
+using ICSharpCode.AvalonEdit.Document;
+using ICSharpCode.AvalonEdit.Editing;
+using ICSharpCode.AvalonEdit.Rendering;
+
+namespace ICSharpCode.AvalonEdit.Search
+{
+	public class SearchPanel
+	{
+		TextArea textArea;
+		StackPanel searchBox;
+		TextBox searchTextBox;
+		Border layer;
+		SearchResultBackgroundRenderer renderer;
+		
+		
+		public SearchPanel(TextArea textArea)
+		{
+			if (textArea == null)
+				throw new ArgumentNullException("textArea");
+			this.textArea = textArea;
+			
+			searchBox = new StackPanel { Orientation = Orientation.Horizontal, Margin = new Thickness(3) };
+			searchBox.KeyDown += SearchLayerKeyDown;
+			layer = new Border {
+				Child = searchBox,
+				Background = Brushes.WhiteSmoke,
+				VerticalAlignment = VerticalAlignment.Top,
+				HorizontalAlignment = HorizontalAlignment.Right,
+				Cursor = Cursors.Arrow
+			};
+			
+			var closeButton = new Button {
+				Content = "x",
+				Margin = new Thickness(3)
+			};
+			closeButton.Click += delegate { Uninstall(); };
+			
+			searchTextBox = new TextBox {
+				Width = 150, Height = 24
+			};
+			searchTextBox.TextChanged += SearchTextBoxTextChanged;
+			
+			searchBox.Children.Add(closeButton);
+			searchBox.Children.Add(searchTextBox);
+			
+			textArea.TextView.Layers.Add(layer);
+			
+			renderer = new SearchResultBackgroundRenderer();
+			textArea.TextView.BackgroundRenderers.Add(renderer);
+			
+			searchTextBox.Focus();
+		}
+
+		void SearchTextBoxTextChanged(object sender, TextChangedEventArgs e)
+		{
+			renderer.CurrentResults.Clear();
+			if (!string.IsNullOrEmpty(searchTextBox.Text)) {
+				string text = textArea.Document.Text;
+				int lastResult = text.IndexOf(searchTextBox.Text, StringComparison.OrdinalIgnoreCase);
+	
+				while (lastResult > -1) {
+					renderer.CurrentResults.Add(new SearchResult { StartOffset = lastResult, Length = searchTextBox.Text.Length });
+					lastResult = text.IndexOf(searchTextBox.Text, lastResult + searchTextBox.Text.Length, StringComparison.OrdinalIgnoreCase);
+				}
+			}
+			textArea.TextView.InvalidateLayer(KnownLayer.Selection);
+		}
+
+		void SearchLayerKeyDown(object sender, KeyEventArgs e)
+		{
+			if (e.Key == Key.Escape) {
+				Uninstall();
+			}
+		}
+
+		void Uninstall()
+		{
+			textArea.TextView.Layers.Remove(layer);
+			textArea.TextView.BackgroundRenderers.Remove(renderer);
+		}
+	}
+	
+	class SearchResult : TextSegment
+	{
+	}
+	
+	class SearchResultBackgroundRenderer : IBackgroundRenderer
+	{
+		TextSegmentCollection<SearchResult> currentResults = new TextSegmentCollection<SearchResult>();
+		
+		public TextSegmentCollection<SearchResult> CurrentResults {
+			get { return currentResults; }
+		}
+		
+		public KnownLayer Layer {
+			get {
+				// draw behind selection
+				return KnownLayer.Selection;
+			}
+		}
+		
+		public void Draw(TextView textView, DrawingContext drawingContext)
+		{
+			if (textView == null)
+				throw new ArgumentNullException("textView");
+			if (drawingContext == null)
+				throw new ArgumentNullException("drawingContext");
+			
+			if (currentResults == null || !textView.VisualLinesValid)
+				return;
+			
+			var visualLines = textView.VisualLines;
+			if (visualLines.Count == 0)
+				return;
+			
+			int viewStart = visualLines.First().FirstDocumentLine.Offset;
+			int viewEnd = visualLines.Last().LastDocumentLine.EndOffset;
+			
+			foreach (SearchResult result in currentResults.FindOverlappingSegments(viewStart, viewEnd - viewStart)) {
+				BackgroundGeometryBuilder geoBuilder = new BackgroundGeometryBuilder();
+				geoBuilder.AlignToWholePixels = true;
+				geoBuilder.CornerRadius = 3;
+				geoBuilder.AddSegment(textView, result);
+				Geometry geometry = geoBuilder.CreateGeometry();
+				if (geometry != null) {
+					SolidColorBrush brush = new SolidColorBrush(Colors.LightGreen);
+					brush.Freeze();
+					drawingContext.DrawGeometry(brush, null, geometry);
+				}
+			}
+		}
+	}
+}