Add ISegment and ITextEditor interfaces.

ICSharpCode.Editor/IDocument.cs

@@ -59,6 +59,7 @@ namespace ICSharpCode.Editor
 		/// <remarks>
 		/// Anchors positioned exactly at the insertion offset will move according to their movement type.
 		/// For AnchorMovementType.Default, they will move behind the inserted text.
+		/// The caret will also move behind the inserted text.
 		/// </remarks>
 		void Insert(int offset, string text);
 		
@@ -70,6 +71,7 @@ namespace ICSharpCode.Editor
 		/// <param name="defaultAnchorMovementType">
 		/// Anchors positioned exactly at the insertion offset will move according to the anchor's movement type.
 		/// For AnchorMovementType.Default, they will move according to the movement type specified by this parameter.
+		/// The caret will also move according to the <paramref name="defaultAnchorMovementType"/> parameter.
 		/// </param>
 		void Insert(int offset, string text, AnchorMovementType defaultAnchorMovementType);
 		

ICSharpCode.Editor/IDocumentLine.cs

@@ -8,23 +8,8 @@ namespace ICSharpCode.Editor
 	/// <summary>
 	/// A line inside a <see cref="IDocument"/>.
 	/// </summary>
-	public interface IDocumentLine
+	public interface IDocumentLine : ISegment
 	{
-		/// <summary>
-		/// Gets the starting offset of the line in the document's text.
-		/// </summary>
-		int Offset { get; }
-		
-		/// <summary>
-		/// Gets the length of this line (=the number of characters on the line).
-		/// </summary>
-		int Length { get; }
-		
-		/// <summary>
-		/// Gets the ending offset of the line in the document's text (= Offset + Length).
-		/// </summary>
-		int EndOffset { get; }
-		
 		/// <summary>
 		/// Gets the length of this line, including the line delimiter.
 		/// </summary>
@@ -41,10 +26,5 @@ namespace ICSharpCode.Editor
 		/// The first line has the number 1.
 		/// </summary>
 		int LineNumber { get; }
-		
-		/// <summary>
-		/// Gets the text on this line.
-		/// </summary>
-		string Text { get; }
 	}
 }

ICSharpCode.Editor/ISegment.cs

@@ -0,0 +1,30 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under MIT license (for details please see \doc\license.txt)
+
+using System;
+
+namespace ICSharpCode.Editor
+{
+	/// <summary>
+	/// An (Offset,Length)-pair.
+	/// </summary>
+	public interface ISegment
+	{
+		/// <summary>
+		/// Gets the start offset of the segment.
+		/// </summary>
+		int Offset { get; }
+		
+		/// <summary>
+		/// Gets the length of the segment.
+		/// </summary>
+		/// <remarks>Must not be negative.</remarks>
+		int Length { get; }
+		
+		/// <summary>
+		/// Gets the end offset of the segment.
+		/// </summary>
+		/// <remarks>EndOffset = Offset + Length;</remarks>
+		int EndOffset { get; }
+	}
+}

ICSharpCode.Editor/ITextBuffer.cs

@@ -77,6 +77,12 @@ namespace ICSharpCode.Editor
 		///  it doesn't require creating a String object for the whole document.</remarks>
 		string GetText(int offset, int length);
 		
+		/// <summary>
+		/// Retrieves the text for a portion of the document.
+		/// </summary>
+		/// <exception cref="ArgumentOutOfRangeException">offset or length is outside the valid range.</exception>
+		string GetText(ISegment segment);
+		
 		/// <summary>
 		/// Gets the index of the first occurrence of any character in the specified array.
 		/// </summary>

ICSharpCode.Editor/ITextEditor.cs

@@ -0,0 +1,100 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under MIT license (for details please see \doc\license.txt)
+
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace ICSharpCode.Editor
+{
+	/// <summary>
+	/// Interface for text editors.
+	/// </summary>
+	public interface ITextEditor : IServiceProvider
+	{
+		/// <summary>
+		/// Gets the document that is being edited.
+		/// </summary>
+		IDocument Document { get; }
+		
+		/// <summary>
+		/// Gets an object that represents the caret inside this text editor.
+		/// </summary>
+		ITextEditorCaret Caret { get; }
+		
+		/// <summary>
+		/// Sets the caret to the specified line/column and brings the caret into view.
+		/// </summary>
+		void JumpTo(int line, int column);
+		
+		/// <summary>
+		/// Gets the start offset of the selection.
+		/// </summary>
+		int SelectionStart { get; }
+		
+		/// <summary>
+		/// Gets the length of the selection.
+		/// </summary>
+		int SelectionLength { get; }
+		
+		/// <summary>
+		/// Gets/Sets the selected text.
+		/// </summary>
+		string SelectedText { get; set; }
+		
+		/// <summary>
+		/// Sets the selection.
+		/// </summary>
+		/// <param name="selectionStart">Start offset of the selection</param>
+		/// <param name="selectionLength">Length of the selection</param>
+		void Select(int selectionStart, int selectionLength);
+		
+		/// <summary>
+		/// Shows the specified linked elements, and allows the user to edit them.
+		/// </summary>
+		/// <returns>
+		/// Returns true when the user has finished editing the elements and pressed Return;
+		/// or false when editing is aborted for any reason.
+		/// </returns>
+		/// <remarks>
+		/// The user can also edit other parts of the document (or other documents) while in link mode.
+		/// In case of success (true return value), this method will update the offsets of the linked elements
+		/// to reflect the changes done by the user.
+		/// If the text editor does not support link mode, it will immediately return false.
+		/// </remarks>
+		Task<bool> ShowLinkedElements(IEnumerable<LinkedElement> linkedElements);
+	}
+	
+	/// <summary>
+	/// Represents the caret in a text editor.
+	/// </summary>
+	public interface ITextEditorCaret
+	{
+		/// <summary>
+		/// Gets/Sets the caret offset;
+		/// </summary>
+		int Offset { get; set; }
+		
+		/// <summary>
+		/// Gets/Sets the caret line number.
+		/// Line numbers are counted starting from 1.
+		/// </summary>
+		int Line { get; set; }
+		
+		/// <summary>
+		/// Gets/Sets the caret column number.
+		/// Column numbers are counted starting from 1.
+		/// </summary>
+		int Column { get; set; }
+		
+		/// <summary>
+		/// Gets/sets the caret location.
+		/// </summary>
+		TextLocation Location { get; set; }
+		
+		/// <summary>
+		/// Is raised whenever the location of the caret has changed.
+		/// </summary>
+		event EventHandler LocationChanged;
+	}
+}

ICSharpCode.Editor/LinkedElement.cs

@@ -0,0 +1,63 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under MIT license (for details please see \doc\license.txt)
+
+using System;
+
+namespace ICSharpCode.Editor
+{
+	/// <summary>
+	/// Represents an element in the text editor that is either editable, or bound to another editable element.
+	/// Used with <see cref="ITextEditor.ShowLinkedElements"/>
+	/// </summary>
+	public class LinkedElement
+	{
+		LinkedElement boundTo;
+		
+		/// <summary>
+		/// Gets/Sets the start offset of this linked element.
+		/// </summary>
+		public int StartOffset { get; set; }
+		
+		/// <summary>
+		/// Gets/Sets the end offset of this linked element.
+		/// </summary>
+		public int EndOffset { get; set; }
+		
+		/// <summary>
+		/// Gets the linked element to which this element is bound.
+		/// </summary>
+		public LinkedElement BoundTo {
+			get { return boundTo; }
+		}
+		
+		/// <summary>
+		/// Gets whether this element is editable. Returns true if this element is not bound.
+		/// </summary>
+		public bool IsEditable {
+			get { return boundTo == null; }
+		}
+		
+		/// <summary>
+		/// Creates a new editable element.
+		/// </summary>
+		public LinkedElement(int startOffset, int endOffset)
+		{
+			this.StartOffset = startOffset;
+			this.EndOffset = endOffset;
+		}
+		
+		/// <summary>
+		/// Creates a new element that is bound to <paramref name="boundTo"/>.
+		/// </summary>
+		public LinkedElement(int startOffset, int endOffset, LinkedElement boundTo)
+		{
+			if (boundTo == null)
+				throw new ArgumentNullException("boundTo");
+			this.StartOffset = startOffset;
+			this.EndOffset = endOffset;
+			while (boundTo.boundTo != null)
+				boundTo = boundTo.boundTo;
+			this.boundTo = boundTo;
+		}
+	}
+}

ICSharpCode.Editor/ReadOnlyDocument.cs

@@ -306,6 +306,12 @@ namespace ICSharpCode.Editor
 			return textBuffer.GetText(offset, length);
 		}
 		
+		/// <inheritdoc/>
+		public string GetText(ISegment segment)
+		{
+			return textBuffer.GetText(segment);
+		}
+		
 		/// <inheritdoc/>
 		public int IndexOfAny(char[] anyOf, int startIndex, int count)
 		{

ICSharpCode.Editor/StringTextBuffer.cs

@@ -76,6 +76,14 @@ namespace ICSharpCode.Editor
 			return text.Substring(offset, length);
 		}
 		
+		/// <inheritdoc/>
+		public string GetText(ISegment segment)
+		{
+			if (segment == null)
+				throw new ArgumentNullException("segment");
+			return text.Substring(segment.Offset, segment.Length);
+		}
+		
 		/// <inheritdoc/>
 		public int IndexOfAny(char[] anyOf, int startIndex, int count)
 		{