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diff --git a/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Snippets/InsertionContext.cs b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Snippets/InsertionContext.cs
new file mode 100644
index 000000000..d7de8311d
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+++ b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Snippets/InsertionContext.cs
@@ -0,0 +1,269 @@
+// 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.Collections.Generic;
+using System.Windows;
+using System.Windows.Input;
+
+using Tango.Scripting.Editors.Document;
+using Tango.Scripting.Editors.Editing;
+using Tango.Scripting.Editors.Utils;
+
+namespace Tango.Scripting.Editors.Snippets
+{
+	/// <summary>
+	/// Represents the context of a snippet insertion.
+	/// </summary>
+	public class InsertionContext : IWeakEventListener
+	{
+		enum Status
+		{
+			Insertion,
+			RaisingInsertionCompleted,
+			Interactive,
+			RaisingDeactivated,
+			Deactivated
+		}
+		
+		Status currentStatus = Status.Insertion;
+		
+		/// <summary>
+		/// Creates a new InsertionContext instance.
+		/// </summary>
+		public InsertionContext(TextArea textArea, int insertionPosition)
+		{
+			if (textArea == null)
+				throw new ArgumentNullException("textArea");
+			this.TextArea = textArea;
+			this.Document = textArea.Document;
+			this.SelectedText = textArea.Selection.GetText();
+			this.InsertionPosition = insertionPosition;
+			this.startPosition = insertionPosition;
+			
+			DocumentLine startLine = this.Document.GetLineByOffset(insertionPosition);
+			ISegment indentation = TextUtilities.GetWhitespaceAfter(this.Document, startLine.Offset);
+			this.Indentation = Document.GetText(indentation.Offset, Math.Min(indentation.EndOffset, insertionPosition) - indentation.Offset);
+			this.Tab = textArea.Options.IndentationString;
+			
+			this.LineTerminator = TextUtilities.GetNewLineFromDocument(this.Document, startLine.LineNumber);
+		}
+		
+		/// <summary>
+		/// Gets the text area.
+		/// </summary>
+		public TextArea TextArea { get; private set; }
+		
+		/// <summary>
+		/// Gets the text document.
+		/// </summary>
+		public TextDocument Document { get; private set; }
+		
+		/// <summary>
+		/// Gets the text that was selected before the insertion of the snippet.
+		/// </summary>
+		public string SelectedText { get; private set; }
+		
+		/// <summary>
+		/// Gets the indentation at the insertion position.
+		/// </summary>
+		public string Indentation { get; private set; }
+		
+		/// <summary>
+		/// Gets the indentation string for a single indentation level.
+		/// </summary>
+		public string Tab { get; private set; }
+		
+		/// <summary>
+		/// Gets the line terminator at the insertion position.
+		/// </summary>
+		public string LineTerminator { get; private set; }
+		
+		/// <summary>
+		/// Gets/Sets the insertion position.
+		/// </summary>
+		public int InsertionPosition { get; set; }
+		
+		readonly int startPosition;
+		AnchorSegment wholeSnippetAnchor;
+		bool deactivateIfSnippetEmpty;
+		
+		/// <summary>
+		/// Gets the start position of the snippet insertion.
+		/// </summary>
+		public int StartPosition {
+			get {
+				if (wholeSnippetAnchor != null)
+					return wholeSnippetAnchor.Offset;
+				else
+					return startPosition;
+			}
+		}
+		
+		/// <summary>
+		/// Inserts text at the insertion position and advances the insertion position.
+		/// This method will add the current indentation to every line in <paramref name="text"/> and will
+		/// replace newlines with the expected newline for the document.
+		/// </summary>
+		public void InsertText(string text)
+		{
+			if (text == null)
+				throw new ArgumentNullException("text");
+			if (currentStatus != Status.Insertion)
+				throw new InvalidOperationException();
+			
+			text = text.Replace("\t", this.Tab);
+			
+			using (this.Document.RunUpdate()) {
+				int textOffset = 0;
+				SimpleSegment segment;
+				while ((segment = NewLineFinder.NextNewLine(text, textOffset)) != SimpleSegment.Invalid) {
+					string insertString = text.Substring(textOffset, segment.Offset - textOffset)
+						+ this.LineTerminator + this.Indentation;
+					this.Document.Insert(InsertionPosition, insertString);
+					this.InsertionPosition += insertString.Length;
+					textOffset = segment.EndOffset;
+				}
+				string remainingInsertString = text.Substring(textOffset);
+				this.Document.Insert(InsertionPosition, remainingInsertString);
+				this.InsertionPosition += remainingInsertString.Length;
+			}
+		}
+		
+		Dictionary<SnippetElement, IActiveElement> elementMap = new Dictionary<SnippetElement, IActiveElement>();
+		List<IActiveElement> registeredElements = new List<IActiveElement>();
+		
+		/// <summary>
+		/// Registers an active element. Elements should be registered during insertion and will be called back
+		/// when insertion has completed.
+		/// </summary>
+		/// <param name="owner">The snippet element that created the active element.</param>
+		/// <param name="element">The active element.</param>
+		public void RegisterActiveElement(SnippetElement owner, IActiveElement element)
+		{
+			if (owner == null)
+				throw new ArgumentNullException("owner");
+			if (element == null)
+				throw new ArgumentNullException("element");
+			if (currentStatus != Status.Insertion)
+				throw new InvalidOperationException();
+			elementMap.Add(owner, element);
+			registeredElements.Add(element);
+		}
+		
+		/// <summary>
+		/// Returns the active element belonging to the specified snippet element, or null if no such active element is found.
+		/// </summary>
+		public IActiveElement GetActiveElement(SnippetElement owner)
+		{
+			if (owner == null)
+				throw new ArgumentNullException("owner");
+			IActiveElement element;
+			if (elementMap.TryGetValue(owner, out element))
+				return element;
+			else
+				return null;
+		}
+		
+		/// <summary>
+		/// Gets the list of active elements.
+		/// </summary>
+		public IEnumerable<IActiveElement> ActiveElements {
+			get { return registeredElements; }
+		}
+		
+		/// <summary>
+		/// Calls the <see cref="IActiveElement.OnInsertionCompleted"/> method on all registered active elements
+		/// and raises the <see cref="InsertionCompleted"/> event.
+		/// </summary>
+		/// <param name="e">The EventArgs to use</param>
+		[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1030:UseEventsWhereAppropriate",
+		                                                 Justification="There is an event and this method is raising it.")]
+		public void RaiseInsertionCompleted(EventArgs e)
+		{
+			if (currentStatus != Status.Insertion)
+				throw new InvalidOperationException();
+			if (e == null)
+				e = EventArgs.Empty;
+			
+			currentStatus = Status.RaisingInsertionCompleted;
+			int endPosition = this.InsertionPosition;
+			this.wholeSnippetAnchor = new AnchorSegment(Document, startPosition, endPosition - startPosition);
+			TextDocumentWeakEventManager.UpdateFinished.AddListener(Document, this);
+			deactivateIfSnippetEmpty = (endPosition != startPosition);
+			
+			foreach (IActiveElement element in registeredElements) {
+				element.OnInsertionCompleted();
+			}
+			if (InsertionCompleted != null)
+				InsertionCompleted(this, e);
+			currentStatus = Status.Interactive;
+			if (registeredElements.Count == 0) {
+				// deactivate immediately if there are no interactive elements
+				Deactivate(new SnippetEventArgs(DeactivateReason.NoActiveElements));
+			} else {
+				myInputHandler = new SnippetInputHandler(this);
+				// disable existing snippet input handlers - there can be only 1 active snippet
+				foreach (TextAreaStackedInputHandler h in TextArea.StackedInputHandlers) {
+					if (h is SnippetInputHandler)
+						TextArea.PopStackedInputHandler(h);
+				}
+				TextArea.PushStackedInputHandler(myInputHandler);
+			}
+		}
+		
+		SnippetInputHandler myInputHandler;
+		
+		/// <summary>
+		/// Occurs when the all snippet elements have been inserted.
+		/// </summary>
+		public event EventHandler InsertionCompleted;
+		
+		/// <summary>
+		/// Calls the <see cref="IActiveElement.Deactivate"/> method on all registered active elements.
+		/// </summary>
+		/// <param name="e">The EventArgs to use</param>
+		public void Deactivate(SnippetEventArgs e)
+		{
+			if (currentStatus == Status.Deactivated || currentStatus == Status.RaisingDeactivated)
+				return;
+			if (currentStatus != Status.Interactive)
+				throw new InvalidOperationException("Cannot call Deactivate() until RaiseInsertionCompleted() has finished.");
+			if (e == null)
+				e = new SnippetEventArgs(DeactivateReason.Unknown);
+			
+			TextDocumentWeakEventManager.UpdateFinished.RemoveListener(Document, this);
+			currentStatus = Status.RaisingDeactivated;
+			TextArea.PopStackedInputHandler(myInputHandler);
+			foreach (IActiveElement element in registeredElements) {
+				element.Deactivate(e);
+			}
+			if (Deactivated != null)
+				Deactivated(this, e);
+			currentStatus = Status.Deactivated;
+		}
+		
+		/// <summary>
+		/// Occurs when the interactive mode is deactivated.
+		/// </summary>
+		public event EventHandler<SnippetEventArgs> Deactivated;
+		
+		bool IWeakEventListener.ReceiveWeakEvent(Type managerType, object sender, EventArgs e)
+		{
+			return ReceiveWeakEvent(managerType, sender, e);
+		}
+		
+		/// <inheritdoc cref="IWeakEventListener.ReceiveWeakEvent"/>
+		protected virtual bool ReceiveWeakEvent(Type managerType, object sender, EventArgs e)
+		{
+			if (managerType == typeof(TextDocumentWeakEventManager.UpdateFinished)) {
+				// Deactivate if snippet is deleted. This is necessary for correctly leaving interactive
+				// mode if Undo is pressed after a snippet insertion.
+				if (wholeSnippetAnchor.Length == 0 && deactivateIfSnippetEmpty)
+					Deactivate(new SnippetEventArgs(DeactivateReason.Deleted));
+				return true;
+			}
+			return false;
+		}
+	}
+}