/*
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Qt Software Information (qt-info@nokia.com)
**
** This file is part of the demonstration applications of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at qt-sales@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/

#include "UBAutoSaver.h"

#include <QtCore>

#include "core/memcheck.h"

#define AUTOSAVE_IN  1000 * 3  // seconds
#define MAXWAIT      1000 * 15 // seconds

UBAutoSaver::UBAutoSaver(QObject *parent) : QObject(parent)
{
    Q_ASSERT(parent);
}


UBAutoSaver::~UBAutoSaver()
{
    if (mTimer.isActive())
        qWarning() << "AutoSaver: still active when destroyed, changes not saved.";
}


void UBAutoSaver::changeOccurred()
{
    if (mFirstChange.isNull())
        mFirstChange.start();

    if (mFirstChange.elapsed() > MAXWAIT)
    {
        saveIfNeccessary();
    } else {
        mTimer.start(AUTOSAVE_IN, this);
    }
}


void UBAutoSaver::timerEvent(QTimerEvent *event)
{
    if (event->timerId() == mTimer.timerId())
    {
        saveIfNeccessary();
    }
    else
    {
        QObject::timerEvent(event);
    }
}


void UBAutoSaver::saveIfNeccessary()
{
    if (!mTimer.isActive())
        return;

    mTimer.stop();
    mFirstChange = QTime();

    if (!QMetaObject::invokeMethod(parent(), "save", Qt::DirectConnection))
    {
        qWarning() << "AutoSaver: error invoking slot save() on parent";
    }
}