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#ifndef QGESTUREMANAGER_P_H
#define QGESTUREMANAGER_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of other Qt classes.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include "qobject.h"
#include "qbasictimer.h"
#include "private/qwidget_p.h"
#include "qgesturerecognizer.h"

QT_BEGIN_NAMESPACE

class QBasicTimer;
class QGraphicsObject;
class QGestureManager : public QObject
{
    Q_OBJECT
public:
    QGestureManager(QObject *parent);
    ~QGestureManager();

    Qt::GestureType registerGestureRecognizer(QGestureRecognizer *recognizer);
    void unregisterGestureRecognizer(Qt::GestureType type);

    bool filterEvent(QWidget *receiver, QEvent *event);
    bool filterEvent(QGesture *receiver, QEvent *event);
    bool filterEvent(QGraphicsObject *receiver, QEvent *event);

    // declared in qapplication.cpp
    static QGestureManager* instance();

protected:
    void timerEvent(QTimerEvent *event);
    bool filterEventThroughContexts(const QMap<QObject *, Qt::GestureType> &contexts,
                                    QEvent *event);

private:
    QMultiMap<Qt::GestureType, QGestureRecognizer *> recognizers;

    QSet<QGesture *> activeGestures;
    QMap<QGesture *, QBasicTimer> maybeGestures;

    enum State {
        Gesture,
        NotGesture,
        MaybeGesture // this means timers are up and waiting for some
                     // more events, and input events are handled by
                     // gesture recognizer explicitely
    } state;

    struct ObjectGesture
    {
        QWeakPointer<QObject> object;
        Qt::GestureType gesture;

        ObjectGesture(QObject *o, const Qt::GestureType &g) : object(o), gesture(g) { }
        inline bool operator<(const ObjectGesture& rhs) const
        {
            if (object.data() < rhs.object.data())
                return true;
            if (object == rhs.object)
                return gesture < rhs.gesture;
            return false;
        }
    };

    QMap<ObjectGesture, QGesture *> objectGestures;
    QMap<QGesture *, QGestureRecognizer *> gestureToRecognizer;
    QHash<QGesture *, QObject *> gestureOwners;

    QHash<QGesture *, QWidget *> gestureTargets;

    int lastCustomGestureId;

    QGesture *getState(QObject *widget, Qt::GestureType gesture);
    void deliverEvents(const QSet<QGesture *> &gestures,
                       QSet<QGesture *> *undeliveredGestures);
    void getGestureTargets(const QSet<QGesture*> &gestures,
                           QMap<QWidget *, QList<QGesture *> > *conflicts,
                           QMap<QWidget *, QList<QGesture *> > *normal);
};

QT_END_NAMESPACE

#endif // QGESTUREMANAGER_P_H