/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef nsTransactionManager_h__
#define nsTransactionManager_h__

#include "prmon.h"
#include "nsWeakReference.h"
#include "nsITransactionManager.h"
#include "nsCOMArray.h"
#include "nsITransactionListener.h"
#include "nsCycleCollectionParticipant.h"

class nsITransaction;
class nsITransactionListener;
class nsTransactionItem;
class nsTransactionStack;
class nsTransactionRedoStack;

/** implementation of a transaction manager object.
 *
 */
class nsTransactionManager : public nsITransactionManager
                           , public nsSupportsWeakReference
{
private:

  PRInt32                mMaxTransactionCount;
  nsTransactionStack     mDoStack;
  nsTransactionStack     mUndoStack;
  nsTransactionRedoStack mRedoStack;
  nsCOMArray<nsITransactionListener> mListeners;

  PRMonitor              *mMonitor;

public:

  /** The default constructor.
   */
  nsTransactionManager(PRInt32 aMaxTransactionCount=-1);

  /** The default destructor.
   */
  virtual ~nsTransactionManager();

  /* Macro for AddRef(), Release(), and QueryInterface() */
  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(nsTransactionManager,
                                           nsITransactionManager)

  /* nsITransactionManager method implementations. */
  NS_DECL_NSITRANSACTIONMANAGER

  /* nsTransactionManager specific methods. */
  virtual nsresult ClearUndoStack(void);
  virtual nsresult ClearRedoStack(void);

  virtual nsresult WillDoNotify(nsITransaction *aTransaction, PRBool *aInterrupt);
  virtual nsresult DidDoNotify(nsITransaction *aTransaction, nsresult aExecuteResult);
  virtual nsresult WillUndoNotify(nsITransaction *aTransaction, PRBool *aInterrupt);
  virtual nsresult DidUndoNotify(nsITransaction *aTransaction, nsresult aUndoResult);
  virtual nsresult WillRedoNotify(nsITransaction *aTransaction, PRBool *aInterrupt);
  virtual nsresult DidRedoNotify(nsITransaction *aTransaction, nsresult aRedoResult);
  virtual nsresult WillBeginBatchNotify(PRBool *aInterrupt);
  virtual nsresult DidBeginBatchNotify(nsresult aResult);
  virtual nsresult WillEndBatchNotify(PRBool *aInterrupt);
  virtual nsresult DidEndBatchNotify(nsresult aResult);
  virtual nsresult WillMergeNotify(nsITransaction *aTop,
                                   nsITransaction *aTransaction,
                                   PRBool *aInterrupt);
  virtual nsresult DidMergeNotify(nsITransaction *aTop,
                                  nsITransaction *aTransaction,
                                  PRBool aDidMerge,
                                  nsresult aMergeResult);

private:

  /* nsTransactionManager specific private methods. */
  virtual nsresult BeginTransaction(nsITransaction *aTransaction);
  virtual nsresult EndTransaction(void);
  virtual nsresult Lock(void);
  virtual nsresult Unlock(void);
};

#endif // nsTransactionManager_h__