qpageranges.cpp

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// Copyright (C) 2020 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qpageranges.h"
#include "qpageranges_p.h"
 
#include <QtCore/qstack.h>
#include <QtCore/qdebug.h>
#include <QtCore/qdatastream.h>
 
QT_BEGIN_NAMESPACE
 
QT_IMPL_METATYPE_EXTERN(QPageRanges)
 
void QPageRangesPrivate::mergeIntervals()
{
    const int count = intervals.size();
 
    if (count <= 1)
        return;
 
    std::sort(intervals.begin(), intervals.end());
 
    QStack<QPageRanges::Range> stack;
    stack.push(intervals[0]);
 
    for (int i = 1; i < count; ++i) {
        QPageRanges::Range &top = stack.top();
 
        if (top.to < intervals[i].from - 1)
            stack.push(intervals[i]);
        else if (top.to < intervals[i].to)
            top.to = intervals[i].to;
    }
 
    intervals = stack;
}
 
QT_DEFINE_QESDP_SPECIALIZATION_DTOR(QPageRangesPrivate)
 
 
QPageRanges::QPageRanges() = default;
 
QPageRanges::QPageRanges(const QPageRanges &other) noexcept = default;
 
QPageRanges::~QPageRanges() = default;
 
QPageRanges &QPageRanges::operator=(const QPageRanges &other) noexcept = default;
 
void QPageRanges::addPage(int pageNumber)
{
    if (pageNumber <= 0) {
        qWarning("QPageRanges::addPage: 'pageNumber' must be greater than 0");
        return;
    }
 
    detach();
    d->intervals.append({ pageNumber, pageNumber });
    d->mergeIntervals();
}
 
void QPageRanges::addRange(int from, int to)
{
    if (from <= 0 || to <= 0) {
        qWarning("QPageRanges::addRange: 'from' and 'to' must be greater than 0");
        return;
    }
    if (to < from)
        std::swap(from, to);
 
    detach();
    d->intervals.append({from, to});
    d->mergeIntervals();
}
 
QList<QPageRanges::Range> QPageRanges::toRangeList() const
{
    if (d)
        return d->intervals;
    return QList<QPageRanges::Range>{};
}
 
void QPageRanges::clear()
{
    d.reset();
}
 
QPageRanges QPageRanges::fromString(const QString &ranges)
{
    QList<Range> intervals;
    const QStringList items = ranges.split(u',');
    for (const QString &item : items) {
        if (item.isEmpty())
            return QPageRanges();
 
        if (item.contains(u'-')) {
            const QStringList rangeItems = item.split(u'-');
            if (rangeItems.size() != 2)
                return QPageRanges();
 
            bool ok;
            const int number1 = rangeItems[0].toInt(&ok);
            if (!ok)
                return QPageRanges();
 
            const int number2 = rangeItems[1].toInt(&ok);
            if (!ok)
                return QPageRanges();
 
            if (number1 < 1 || number2 < 1 || number2 < number1)
                return QPageRanges();
 
            intervals.append({number1, number2});
 
        } else {
            bool ok;
            const int number = item.toInt(&ok);
            if (!ok)
                return QPageRanges();
 
            if (number < 1)
                return QPageRanges();
 
            intervals.append({number, number});
        }
    }
 
    QPageRanges newRanges;
    newRanges.d.reset(new QPageRangesPrivate);
    newRanges.d->intervals = intervals;
    newRanges.d->mergeIntervals();
    return newRanges;
}
 
QString QPageRanges::toString() const
{
    if (!d)
        return QString();
 
    QString result;
    for (const Range &range : d->intervals) {
        if (!result.isEmpty())
            result += u',';
 
        if (range.from == range.to)
            result += QString::number(range.from);
        else
            result += QStringLiteral("%1-%2").arg(range.from).arg(range.to);
    }
 
    return result;
}
 
bool QPageRanges::contains(int pageNumber) const
{
    if (!d)
        return false;
 
    for (const Range &range : d->intervals) {
        if (range.from <= pageNumber && range.to >= pageNumber)
            return true;
    }
    return false;
}
 
bool QPageRanges::isEmpty() const
{
    return !d || d->intervals.isEmpty();
}
 
int QPageRanges::firstPage() const
{
    if (isEmpty())
        return 0;
    return d->intervals.constFirst().from;
}
 
int QPageRanges::lastPage() const
{
    if (isEmpty())
        return 0;
    return d->intervals.constLast().to;
}
 
bool QPageRanges::isEqual(const QPageRanges &other) const noexcept
{
    if (d == other.d)
        return true;
    if (!d || !other.d)
        return false;
    return d->intervals == other.d->intervals;
}
 
void QPageRanges::detach()
{
    if (d)
        d.detach();
    else
        d.reset(new QPageRangesPrivate);
}
 
#if !defined(QT_NO_DATASTREAM)
QDataStream &operator<<(QDataStream &s, const QPageRanges &pageRanges)
{
    s << pageRanges.toString();
    return s;
}
 
QDataStream &operator>>(QDataStream &s, QPageRanges &pageRanges)
{
    QString rangesString;
    s >> rangesString;
    pageRanges = QPageRanges::fromString(rangesString);
    return s;
}
#endif // QT_NO_DATASTREAM
 
#ifndef QT_NO_DEBUG_STREAM
QDebug operator<<(QDebug dbg, const QPageRanges &pageRanges)
{
    QDebugStateSaver saver(dbg);
    dbg.nospace();
    dbg.noquote();
    dbg << "QPageRanges(" << pageRanges.toString() << ")";
 
    return dbg;
}
#endif
 
QT_END_NAMESPACE