//
// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License. See License.txt in the project root for license information.
//
// This file contain implementations details that are subject to change without notice.
// Use at your own risk.
//
namespace Microsoft.VisualStudio.Text.BufferUndoManager.Implementation
{
using System;
using System.ComponentModel.Composition;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Operations;
[Export(typeof(ITextBufferUndoManagerProvider))]
internal sealed class TextBufferUndoManagerProvider : ITextBufferUndoManagerProvider
{
[Import]
internal ITextUndoHistoryRegistry _undoHistoryRegistry { get; set; }
#if false
[Import]
internal IEditorOperationsFactoryService _editorOperationsFactoryService { get; set; }
#endif
///
/// Provides an for the given .
///
/// The to create the for.
/// A cached for the given .
/// is null.
public ITextBufferUndoManager GetTextBufferUndoManager(ITextBuffer textBuffer)
{
// Validate
if (textBuffer == null)
{
throw new ArgumentNullException(nameof(textBuffer));
}
// See if there was already a TextBufferUndoManager created for the given textBuffer, we only ever want to create one
ITextBufferUndoManager cachedBufferUndoManager;
if (!textBuffer.Properties.TryGetProperty(typeof(ITextBufferUndoManager), out cachedBufferUndoManager))
{
#if false
cachedBufferUndoManager = new TextBufferUndoManager(textBuffer, _undoHistoryRegistry, _editorOperationsFactoryService);
#endif
cachedBufferUndoManager = new TextBufferUndoManager(textBuffer, _undoHistoryRegistry);
textBuffer.Properties.AddProperty(typeof(ITextBufferUndoManager), cachedBufferUndoManager);
}
return cachedBufferUndoManager;
}
///
/// If the specified has an associated with it, remove it.
///
/// is null.
public void RemoveTextBufferUndoManager(ITextBuffer textBuffer)
{
// Validate
if (textBuffer == null)
{
throw new ArgumentNullException(nameof(textBuffer));
}
ITextBufferUndoManager cachedBufferUndoManager;
if (textBuffer.Properties.TryGetProperty(typeof(ITextBufferUndoManager), out cachedBufferUndoManager))
{
// Dispose() so it stops listening to Changed events on the buffer.
IDisposable disposableBufferUndoManager = cachedBufferUndoManager as IDisposable;
if (disposableBufferUndoManager != null)
{
disposableBufferUndoManager.Dispose();
}
// Remove from cache.
textBuffer.Properties.RemoveProperty(typeof(ITextBufferUndoManager));
}
}
}
}