/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Licensees holding valid Qt Enterprise licenses may use this file in
** accordance with the Qt Enterprise License Agreement provided with the 
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  
**
** If you have questions regarding the use of this file, please use
** contact form at http://qt.digia.com
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QTIMESTAMP_H
#define QTIMESTAMP_H

#include <QtCore/qglobal.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Core)

class Q_CORE_EXPORT QElapsedTimer
{
public:
    enum ClockType {
        SystemTime,
        MonotonicClock,
        TickCounter,
        MachAbsoluteTime,
        PerformanceCounter
    };
    static ClockType clockType();
    static bool isMonotonic();

    void start();
    qint64 restart();
    void invalidate();
    bool isValid() const;

    qint64 nsecsElapsed() const;
    qint64 elapsed() const;
    bool hasExpired(qint64 timeout) const;

    qint64 msecsSinceReference() const;
    qint64 msecsTo(const QElapsedTimer &other) const;
    qint64 secsTo(const QElapsedTimer &other) const;

    bool operator==(const QElapsedTimer &other) const
    { return t1 == other.t1 && t2 == other.t2; }
    bool operator!=(const QElapsedTimer &other) const
    { return !(*this == other); }

    friend bool Q_CORE_EXPORT operator<(const QElapsedTimer &v1, const QElapsedTimer &v2);

private:
    qint64 t1;
    qint64 t2;
};

QT_END_NAMESPACE

QT_END_HEADER

#endif // QTIMESTAMP_H
