/* -*- 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) 2003
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Dave Hyatt <hyatt@mozilla.org> (Original Author)
 *   Jan Varga <varga@ku.sk>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either 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
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 * the provisions above, a recipient may use your version of this file under
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 * ***** END LICENSE BLOCK ***** */

#ifndef nsTreeImageListener_h__
#define nsTreeImageListener_h__

#include "nsString.h"
#include "nsCOMPtr.h"
#include "nsITreeColumns.h"
#include "nsStubImageDecoderObserver.h"
#include "nsTreeBodyFrame.h"

// This class handles image load observation.
class nsTreeImageListener : public nsStubImageDecoderObserver
{
public:
  nsTreeImageListener(nsTreeBodyFrame *aTreeFrame);
  ~nsTreeImageListener();

  NS_DECL_ISUPPORTS
  // imgIDecoderObserver (override nsStubImageDecoderObserver)
  NS_IMETHOD OnStartContainer(imgIRequest *aRequest, imgIContainer *aImage);
  NS_IMETHOD OnImageIsAnimated(imgIRequest* aRequest);
  NS_IMETHOD OnDataAvailable(imgIRequest *aRequest, bool aCurrentFrame,
                             const nsIntRect *aRect);
  // imgIContainerObserver (override nsStubImageDecoderObserver)
  NS_IMETHOD FrameChanged(imgIRequest *aRequest,
                          imgIContainer *aContainer,
                          const nsIntRect *aDirtyRect);

  NS_IMETHOD ClearFrame();

  friend class nsTreeBodyFrame;

protected:
  void UnsuppressInvalidation() { mInvalidationSuppressed = false; }
  void Invalidate();
  void AddCell(PRInt32 aIndex, nsITreeColumn* aCol);

private:
  nsTreeBodyFrame* mTreeFrame;

  // A guard that prevents us from recursive painting.
  bool mInvalidationSuppressed;

  class InvalidationArea {
    public:
      InvalidationArea(nsITreeColumn* aCol);
      ~InvalidationArea() { delete mNext; }

      friend class nsTreeImageListener;

    protected:
      void AddRow(PRInt32 aIndex);
      nsITreeColumn* GetCol() { return mCol.get(); }
      PRInt32 GetMin() { return mMin; }
      PRInt32 GetMax() { return mMax; }
      InvalidationArea* GetNext() { return mNext; }
      void SetNext(InvalidationArea* aNext) { mNext = aNext; }

    private:
      nsCOMPtr<nsITreeColumn> mCol;
      PRInt32                 mMin;
      PRInt32                 mMax;
      InvalidationArea*       mNext;
  };

  InvalidationArea* mInvalidationArea;
};

#endif // nsTreeImageListener_h__
