1 files changed, 123 insertions, 0 deletions
diff --git a/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Rendering/VisualLineTextSource.cs b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Rendering/VisualLineTextSource.cs
new file mode 100644
index 000000000..3a5167010
--- /dev/null
+++ b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Rendering/VisualLineTextSource.cs
@@ -0,0 +1,123 @@
+// 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.Diagnostics;
+using System.Windows.Media.TextFormatting;
+
+using Tango.Scripting.Editors.Document;
+using Tango.Scripting.Editors.Utils;
+
+namespace Tango.Scripting.Editors.Rendering
+{
+	/// <summary>
+	/// WPF TextSource implementation that creates TextRuns for a VisualLine.
+	/// </summary>
+	sealed class VisualLineTextSource : TextSource, ITextRunConstructionContext
+	{
+		public VisualLineTextSource(VisualLine visualLine)
+		{
+			this.VisualLine = visualLine;
+		}
+		
+		public VisualLine VisualLine { get; private set; }
+		public TextView TextView { get; set; }
+		public TextDocument Document { get; set; }
+		public TextRunProperties GlobalTextRunProperties { get; set; }
+		
+		public override TextRun GetTextRun(int textSourceCharacterIndex)
+		{
+			try {
+				foreach (VisualLineElement element in VisualLine.Elements) {
+					if (textSourceCharacterIndex >= element.VisualColumn
+					    && textSourceCharacterIndex < element.VisualColumn + element.VisualLength)
+					{
+						int relativeOffset = textSourceCharacterIndex - element.VisualColumn;
+						TextRun run = element.CreateTextRun(textSourceCharacterIndex, this);
+						if (run == null)
+							throw new ArgumentNullException(element.GetType().Name + ".CreateTextRun");
+						if (run.Length == 0)
+							throw new ArgumentException("The returned TextRun must not have length 0.", element.GetType().Name + ".Length");
+						if (relativeOffset + run.Length > element.VisualLength)
+							throw new ArgumentException("The returned TextRun is too long.", element.GetType().Name + ".CreateTextRun");
+						InlineObjectRun inlineRun = run as InlineObjectRun;
+						if (inlineRun != null) {
+							inlineRun.VisualLine = VisualLine;
+							VisualLine.hasInlineObjects = true;
+							TextView.AddInlineObject(inlineRun);
+						}
+						return run;
+					}
+				}
+				if (TextView.Options.ShowEndOfLine && textSourceCharacterIndex == VisualLine.VisualLength) {
+					return CreateTextRunForNewLine();
+				}
+				return new TextEndOfParagraph(1);
+			} catch (Exception ex) {
+				Debug.WriteLine(ex.ToString());
+				throw;
+			}
+		}
+
+		TextRun CreateTextRunForNewLine()
+		{
+			string newlineText = "";
+			DocumentLine lastDocumentLine = VisualLine.LastDocumentLine;
+			if (lastDocumentLine.DelimiterLength == 2) {
+				newlineText = "¶";
+			} else if (lastDocumentLine.DelimiterLength == 1) {
+				char newlineChar = Document.GetCharAt(lastDocumentLine.Offset + lastDocumentLine.Length);
+				if (newlineChar == '\r')
+					newlineText = "\\r";
+				else if (newlineChar == '\n')
+					newlineText = "\\n";
+				else
+					newlineText = "?";
+			}
+			return new FormattedTextRun(new FormattedTextElement(TextView.cachedElements.GetTextForNonPrintableCharacter(newlineText, this), 0), GlobalTextRunProperties);
+		}
+		
+		public override TextSpan<CultureSpecificCharacterBufferRange> GetPrecedingText(int textSourceCharacterIndexLimit)
+		{
+			try {
+				foreach (VisualLineElement element in VisualLine.Elements) {
+					if (textSourceCharacterIndexLimit > element.VisualColumn
+					    && textSourceCharacterIndexLimit <= element.VisualColumn + element.VisualLength)
+					{
+						TextSpan<CultureSpecificCharacterBufferRange> span = element.GetPrecedingText(textSourceCharacterIndexLimit, this);
+						if (span == null)
+							break;
+						int relativeOffset = textSourceCharacterIndexLimit - element.VisualColumn;
+						if (span.Length > relativeOffset)
+							throw new ArgumentException("The returned TextSpan is too long.", element.GetType().Name + ".GetPrecedingText");
+						return span;
+					}
+				}
+				CharacterBufferRange empty = CharacterBufferRange.Empty;
+				return new TextSpan<CultureSpecificCharacterBufferRange>(empty.Length, new CultureSpecificCharacterBufferRange(null, empty));
+			} catch (Exception ex) {
+				Debug.WriteLine(ex.ToString());
+				throw;
+			}
+		}
+		
+		public override int GetTextEffectCharacterIndexFromTextSourceCharacterIndex(int textSourceCharacterIndex)
+		{
+			throw new NotSupportedException();
+		}
+		
+		string cachedString;
+		int cachedStringOffset;
+		
+		public StringSegment GetText(int offset, int length)
+		{
+			if (cachedString != null) {
+				if (offset >= cachedStringOffset && offset + length <= cachedStringOffset + cachedString.Length) {
+					return new StringSegment(cachedString, offset - cachedStringOffset, length);
+				}
+			}
+			cachedStringOffset = offset;
+			return new StringSegment(cachedString = this.Document.GetText(offset, length));
+		}
+	}
+}