source: trunk/src/xmlpatterns/functions/qsequencegeneratingfns.cpp@ 219

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#include <QStack>
#include <QStringList>

#include "qanyuri_p.h"
#include "qboolean_p.h"
#include "qcommonsequencetypes_p.h"
#include "qcommonvalues_p.h"
#include "qemptysequence_p.h"
#include "qitemmappingiterator_p.h"
#include "qnodesort_p.h"
#include "qpatternistlocale_p.h"
#include "private/qxmlutils_p.h"

#include "qsequencegeneratingfns_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

IdFN::IdFN() : m_hasCreatedSorter(false)
{
}

Item IdFN::mapToItem(const QString &id,
                     const IDContext &context) const
{
    return context.second->elementById(context.first->namePool()->allocateQName(QString(), id));
}

/**
 * @short Helper class for StringSplitter
 *
 * Needed by the QAbstractXmlForwardIterator sub-class.
 *
 * @relates StringSplitter
 */
template<>
bool qIsForwardIteratorEnd(const QString &unit)
{
    return unit.isNull();
}

/**
 * @short Helper class for IdFN.
 *
 * StringSplitter takes an Iterator which delivers strings of this kind:
 *
 * "a", "b c", "%invalidNCName", "  ", "d"
 *
 * and we deliver instead:
 *
 * "a", "b", "c", "d"
 *
 * That is, we:
 * - Remove invalid @c NCName
 * - Split IDREFs into individual NCNames
 *
 * @author Frans Englich
 */
class StringSplitter : public QAbstractXmlForwardIterator<QString>
{
public:
    StringSplitter(const Item::Iterator::Ptr &source);
    virtual QString next();
    virtual QString current() const;
    virtual qint64 position() const;
private:
    QString loadNext();
    const Item::Iterator::Ptr   m_source;
    QStack<QString>             m_buffer;
    QString                     m_current;
    qint64                      m_position;
    bool                        m_sourceAtEnd;
};

StringSplitter::StringSplitter(const Item::Iterator::Ptr &source) : m_source(source)
                                                                  , m_position(0)
                                                                  , m_sourceAtEnd(false)
{
    Q_ASSERT(m_source);
    m_buffer.push(loadNext());
}

QString StringSplitter::next()
{
    /* We also check m_position, we want to load on our first run. */
    if(!m_buffer.isEmpty())
    {
        ++m_position;
        m_current = m_buffer.pop();
        return m_current;
    }
    else if(m_sourceAtEnd)
    {
        m_current.clear();
        m_position = -1;
        return QString();
    }

    return loadNext();
}

QString StringSplitter::loadNext()
{
    const Item sourceNext(m_source->next());

    if(sourceNext.isNull())
    {
        m_sourceAtEnd = true;
        /* We might have strings in m_buffer, let's empty it. */
        return next();
    }

    const QStringList candidates(sourceNext.stringValue().simplified().split(QLatin1Char(' ')));
    const int count = candidates.length();

    for(int i = 0; i < count; ++i)
    {
        const QString &at = candidates.at(i);

        if(QXmlUtils::isNCName(at))
            m_buffer.push(at);
    }