// 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

// Qt-Security score:significant reason:default

#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)

/*!

    \class QPageRanges

    \brief The QPageRanges class represents a collection of page ranges.

    \inmodule QtGui

    \ingroup painting

    \ingroup printing

    \ingroup shared

    \since 6.0

    Use QPagedPaintDevice::pageRanges() to access the collection of page ranges

    associated with a paged device.

*/

/*!

    Constructs an empty QPageRanges object.

*/

QPageRanges::QPageRanges() = default;

/*!

    Constructs a QPageRanges object by copying \a other.

*/

QPageRanges::QPageRanges(const QPageRanges &other) noexcept = default;

/*!

    \fn QPageRanges::QPageRanges(QPageRanges &&other)

    Constructs a QPageRanges object by moving from \a other.

*/

/*!

    Destroys the page ranges.

*/

QPageRanges::~QPageRanges() = default;

/*!

    Assigns \a other to this QPageRanges object.

*/

QPageRanges &QPageRanges::operator=(const QPageRanges &other) noexcept = default;

/*!

    \fn QPageRanges &QPageRanges::operator=(QPageRanges &&other)

    Moves \a other into this QPageRanges object.

*/

/*!

    Adds the single page \a pageNumber to the ranges.

    \note Page numbers start with 1. Attempts to add page numbers

    smaller than 1 will be ignored with a warning.

*/

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();

}

/*!

    Adds the range specified with \a from and \a to to the ranges.

    \note Page numbers start with 1. Attempts to add page numbers

    smaller than 1 will be ignored with a warning.

*/

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();

}

/*!

    Returns a list with the values of the ranges.

*/

QList<QPageRanges::Range> QPageRanges::toRangeList() const

{

    if (d)

        return d->intervals;

    return QList<QPageRanges::Range>{};

}

/*!

    Removes all page ranges.

*/

void QPageRanges::clear()

{

    d.reset();

}

/*!

    Constructs and returns a QPageRanges object populated with the

    \a ranges from the string representation.

    \code

    QPrinter printer;

    QPageRanges ranges = QPageRanges::fromString("1-3,6-7");

    printer.setPageRanges(ranges);

    \endcode

    In case of parsing error, returns an empty QPageRanges object.

    \sa isEmpty()

*/

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;

}

/*!

    Returns the string representation of the page ranges.

*/

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;

}

/*!

    \fn bool QPageRanges::contains(int pageNumber) const

    Returns \c true if the ranges include the page \a pageNumber;

    otherwise returns \c false.

*/

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;

}

/*!

    Returns \c true if the ranges are empty; otherwise returns \c false.

*/

bool QPageRanges::isEmpty() const

{

    return !d || d->intervals.isEmpty();

}

/*!

    Returns the index of the first page covered by the page ranges,

    or 0 if the page ranges are empty.

*/

int QPageRanges::firstPage() const

{

    if (isEmpty())

        return 0;

    return d->intervals.constFirst().from;

}

/*!

    Returns the index of the last page covered by the page ranges,

    or 0 if the page ranges are empty.

*/

int QPageRanges::lastPage() const

{

    if (isEmpty())

        return 0;

    return d->intervals.constLast().to;

}

/*!

    \internal

*/

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;

}

/*!

    \internal

*/

void QPageRanges::detach()

{

    if (d)

        d.detach();

    else

        d.reset(new QPageRangesPrivate);

}

#if !defined(QT_NO_DATASTREAM)

/*!

    \fn QDataStream &operator<<(QDataStream &stream, const QPageRanges &pageRanges)

    \relates QPageRanges

    Writes \a pageRanges to \a stream as a range string.

    \sa QPageRanges::toString

*/

QDataStream &operator<<(QDataStream &s, const QPageRanges &pageRanges)

{

    s << pageRanges.toString();

    return s;

}

/*!

    \fn QDataStream &operator>>(QDataStream &stream, QPageRanges &pageRanges)

    \relates QPageRanges

    Reads a page ranges string from \a stream and stores it in \a pageRanges.

    \sa QPageRanges::fromString

*/

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

/*!

    \struct QPageRanges::Range

    \inmodule QtGui

    \brief The QPageRanges::Range struct holds the \c from and \c to endpoints of a range.

    \sa QPageRanges::toRangeList()

*/

/*!

    \variable QPageRanges::Range::from

    \brief the lower endpoint of the range

*/

/*!

    \variable QPageRanges::Range::to

    \brief the upper endpoint of the range

*/

/*!

    \fn bool QPageRanges::Range::contains(int pageNumber) const

    Returns \c true if \a pageNumber is within the interval \c{[from, to]};

    otherwise returns \c false.

*/

QT_END_NAMESPACE