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#ifndef QWINDOWSDRAG_H
#define QWINDOWSDRAG_H

#include "qwindowsinternalmimedata.h"

#include <qpa/qplatformdrag.h>
#include <QtGui/QPixmap>

struct IDropTargetHelper;

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 handleDrag(QWindow *window, DWORD grfKeyState, const QPoint &, LPDWORD pdwEffect);

    ULONG m_refs;
    QWindow *const m_window;
    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 Qt::DropAction drag(QDrag *drag);

    static QWindowsDrag *instance();

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

    IDropTargetHelper* dropHelper();

    QPixmap defaultCursor(Qt::DropAction action) const;

private:
    QWindowsDropMimeData m_dropData;
    IDataObject *m_dropDataObject;

    IDropTargetHelper* m_cachedDropTargetHelper;

    mutable QPixmap m_copyDragCursor;
    mutable QPixmap m_moveDragCursor;
    mutable QPixmap m_linkDragCursor;
    mutable QPixmap m_ignoreDragCursor;
};

QT_END_NAMESPACE

#endif // QWINDOWSDRAG_H