/*
 * Copyright 2006, Haiku.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *              Stephan Aßmus <superstippi@gmx.de>
 */

#ifndef MOUSE_WHEEL_FILTER_H
#define MOUSE_WHEEL_FILTER_H

#include <Message.h>
#include <MessageFilter.h>

class MouseWheelTarget {
 public:
                MouseWheelTarget()
                {
                }
        virtual ~MouseWheelTarget()
                {
                }

        virtual bool MouseWheelChanged(float x, float y) = 0;
};

class MouseWheelFilter : public BMessageFilter {
 public:
        MouseWheelFilter(MouseWheelTarget* target)
                : BMessageFilter(B_ANY_DELIVERY, B_ANY_SOURCE),
                  fTarget(target),
                  fTargetHandler(dynamic_cast<BHandler*>(fTarget))
                {
                }
        virtual ~MouseWheelFilter()
                {
                }
        virtual filter_result   Filter(BMessage* message, BHandler** target)
                {
                        filter_result result = B_DISPATCH_MESSAGE;
                        switch (message->what) {
                                case B_MOUSE_WHEEL_CHANGED: {
                                        float x;
                                        float y;
                                        if (message->FindFloat("be:wheel_delta_x", &x) >= B_OK
                                                && message->FindFloat("be:wheel_delta_y", &y) >= B_OK) {
                                                if (fTarget->MouseWheelChanged(x, y))
                                                        //result = B_SKIP_MESSAGE;
                                                        *target = fTargetHandler;
                                        }
                                        break;
                                }
                                default:
                                        break;
                        }
                        return result;
                }
 private:
        MouseWheelTarget*               fTarget;
        BHandler*                               fTargetHandler;
};

#endif // MOUSE_WHEEL_FILTER_H