/*
 * Copyright 2001-2009, Ingo Weinhold <ingo_weinhold@gmx.de>
 * All rights reserved. Distributed under the terms of the MIT license.
 */
#ifndef SCROLLABLE_H
#define SCROLLABLE_H

#include <Point.h>
#include <Rect.h>

class Scroller;

class Scrollable {
 public:
                                                                Scrollable();
        virtual                                         ~Scrollable();

                        void                            SetScrollSource(Scroller* source);
                        Scroller*                       ScrollSource() const;

                        void                            SetDataRect(BRect dataRect,
                                                                        bool validateScrollOffset = true);
                        BRect                           DataRect() const;

        virtual void                            SetScrollOffset(BPoint offset);
                        BPoint                          ScrollOffset() const;

                        void                            SetDataRectAndScrollOffset(BRect dataRect,
                                                                        BPoint offset);

                        BPoint                          ValidScrollOffsetFor(BPoint offset) const;
                        BPoint                          ValidScrollOffsetFor(BPoint offset,
                                                                        const BRect& dataRect) const;

                        void                            SetVisibleSize(float width, float height);
                        BRect                           VisibleBounds() const;
                        BRect                           VisibleRect() const;

protected:
        virtual void                            DataRectChanged(BRect oldDataRect,
                                                                                                BRect newDataRect);
        virtual void                            ScrollOffsetChanged(BPoint oldOffset,
                                                                                                        BPoint newOffset);
        virtual void                            VisibleSizeChanged(float oldWidth,
                                                                                                   float oldHeight,
                                                                                                   float newWidth,
                                                                                                   float newHeight);
        virtual void                            ScrollSourceChanged(Scroller* oldSource,
                                                                                                        Scroller* newSource);

 private:
                        BRect                           fDataRect;
                        BPoint                          fScrollOffset;
                        float                           fVisibleWidth;
                        float                           fVisibleHeight;
                        Scroller*                       fScrollSource;
};


#endif  // SCROLLABLE_H