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****************************************************************************/

#ifndef QWINDOWSDRAG_H
#define QWINDOWSDRAG_H

#include "qwindowsinternalmimedata.h"

#include <QtGui/QPlatformDrag>

QT_BEGIN_NAMESPACE

class QWindowsDropMimeData : public QWindowsInternalMimeData {
public:
    QWindowsDropMimeData() {}
    virtual IDataObject *retrieveDataObject() const;
};

class QWindowsOleDropTarget : public IDropTarget
{
public:
    explicit QWindowsOleDropTarget(QWindow *w);
    virtual ~QWindowsOleDropTarget();

    // IUnknown methods
    STDMETHOD(QueryInterface)(REFIID riid, void FAR* FAR* ppvObj);
    STDMETHOD_(ULONG, AddRef)(void);
    STDMETHOD_(ULONG, Release)(void);

    // IDropTarget methods
    STDMETHOD(DragEnter)(LPDATAOBJECT pDataObj, DWORD grfKeyState, POINTL pt, LPDWORD pdwEffect);
    STDMETHOD(DragOver)(DWORD grfKeyState, POINTL pt, LPDWORD pdwEffect);
    STDMETHOD(DragLeave)();
    STDMETHOD(Drop)(LPDATAOBJECT pDataObj, DWORD grfKeyState, POINTL pt, LPDWORD pdwEffect);

private:
    inline QWindow *findDragOverWindow(const POINTL &pt) const;
    void sendDragEnterEvent(QWindow *to, DWORD grfKeyState, POINTL pt, LPDWORD pdwEffect);

    ULONG m_refs;
    QWindow *const m_window;
    QWindow *m_currentWindow;
    QRect m_answerRect;
    QPoint m_lastPoint;
    DWORD m_chosenEffect;
    DWORD m_lastKeyState;
};

class QWindowsDrag : public QPlatformDrag
{
public:
    QWindowsDrag();
    virtual ~QWindowsDrag();

    virtual QMimeData *platformDropData() { return &m_dropData; }

    virtual void startDrag();
    virtual void move(const QMouseEvent *me);
    virtual void drop(const QMouseEvent *me);
    virtual void cancel();

    static QWindowsDrag *instance();

    IDataObject *dropDataObject() const             { return m_dropDataObject; }
    void setDropDataObject(IDataObject *dataObject) { m_dropDataObject = dataObject; }
    void releaseDropDataObject();

    bool dragBeingCancelled() const { return m_dragBeingCancelled; }

private:
    QWindowsDropMimeData m_dropData;
    IDataObject *m_dropDataObject;
    bool m_dragBeingCancelled;
};

QT_END_NAMESPACE

#endif // QWINDOWSDRAG_H