/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim:cindent:ts=2:et:sw=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):
 *   Pierre Phaneuf <pp@ludusdesign.com>
 *   Brian Ryner <bryner@brianryner.com>
 *
 * 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 *****
 *
 * This Original Code has been modified by IBM Corporation. Modifications made
 * by IBM described herein are Copyright (c) International Business Machines
 * Corporation, 2000. Modifications to Mozilla code or documentation identified
 * per MPL Section 3.3
 *
 * Date             Modified by     Description of modification
 * 04/20/2000       IBM Corp.      OS/2 VisualAge build.
 */

/* part of nsFrameManager, to work around header inclusionordering */

#ifndef _nsFrameManagerBase_h_
#define _nsFrameManagerBase_h_

#include "pldhash.h"

class nsIPresShell;
class nsStyleSet;
class nsIContent;
class nsPlaceholderFrame;
class nsIFrame;
class nsStyleContext;
class nsIAtom;
class nsStyleChangeList;
class nsILayoutHistoryState;

class nsFrameManagerBase
{
public:
  nsFrameManagerBase()
  {
    memset(this, '\0', sizeof(nsFrameManagerBase));
  }

  bool IsDestroyingFrames() { return mIsDestroyingFrames; }

  /*
   * Gets and sets the root frame (typically the viewport). The lifetime of the
   * root frame is controlled by the frame manager. When the frame manager is
   * destroyed, it destroys the entire frame hierarchy.
   */
  NS_HIDDEN_(nsIFrame*) GetRootFrame() const { return mRootFrame; }
  NS_HIDDEN_(void)      SetRootFrame(nsIFrame* aRootFrame)
  {
    NS_ASSERTION(!mRootFrame, "already have a root frame");
    mRootFrame = aRootFrame;
  }

protected:
  class UndisplayedMap;

  // weak link, because the pres shell owns us
  nsIPresShell*                   mPresShell;
  // the pres shell owns the style set
  nsStyleSet*                     mStyleSet;
  nsIFrame*                       mRootFrame;
  PLDHashTable                    mPlaceholderMap;
  UndisplayedMap*                 mUndisplayedMap;
  bool                            mIsDestroyingFrames;  // The frame manager is destroying some frame(s).
};

#endif