source: trunk/tools/assistant/lib/qhelpsearchengine.cpp@ 315

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#include "qhelpenginecore.h"
#include "qhelpsearchengine.h"
#include "qhelpsearchquerywidget.h"
#include "qhelpsearchresultwidget.h"

#if defined(QT_CLUCENE_SUPPORT)
#   include "qhelpsearchindexreader_clucene_p.h"
#   include "qhelpsearchindexwriter_clucene_p.h"
#else
#   include "qhelpsearchindexreader_default_p.h"
#   include "qhelpsearchindexwriter_default_p.h"
#endif

#include <QtCore/QDir>
#include <QtCore/QFile>
#include <QtCore/QFileInfo>
#include <QtCore/QVariant>
#include <QtCore/QThread>
#include <QtCore/QPointer>

QT_BEGIN_NAMESPACE

#if defined(QT_CLUCENE_SUPPORT)
    using namespace qt::fulltextsearch::clucene;
#else
    using namespace qt::fulltextsearch::std;
#endif

class QHelpSearchEnginePrivate : public QObject
{
    Q_OBJECT

signals:
    void indexingStarted();
    void indexingFinished();

    void searchingStarted();
    void searchingFinished(int hits);

private:
    QHelpSearchEnginePrivate(QHelpEngineCore *helpEngine)
        : queryWidget(0)
        , resultWidget(0)
        , helpEngine(helpEngine)
    {
        hitList.clear();
        indexReader = 0;
        indexWriter = 0;
    }

    ~QHelpSearchEnginePrivate()
    {
        hitList.clear();
        delete indexReader;
        delete indexWriter;
    }

    int hitsCount() const
    {
        int count = 0;
        if (indexReader)
            count = indexReader->hitsCount();

        return count;
    }

    QList<QHelpSearchEngine::SearchHit> hits(int start, int end) const
    {
        QList<QHelpSearchEngine::SearchHit> returnValue;
        if (indexReader) {
            for (int i = start; i < end && i < hitsCount(); ++i)
                returnValue.append(indexReader->hit(i));
        }
        return returnValue;
    }

    void updateIndex(bool reindex = false)
    {
        if (helpEngine.isNull())
            return;

        if (!QFile::exists(QFileInfo(helpEngine->collectionFile()).path()))
            return;

        if (!indexWriter) {
            indexWriter = new QHelpSearchIndexWriter();

            connect(indexWriter, SIGNAL(indexingStarted()), this, SIGNAL(indexingStarted()));
            connect(indexWriter, SIGNAL(indexingFinished()), this, SIGNAL(indexingFinished()));
            connect(indexWriter, SIGNAL(indexingFinished()), this, SLOT(optimizeIndex()));
        }

        if (indexWriter) {
            indexWriter->cancelIndexing();
            indexWriter->updateIndex(helpEngine->collectionFile(),
                indexFilesFolder(), reindex);
        }
    }

    void cancelIndexing()
    {
        if (indexWriter)
            indexWriter->cancelIndexing();
    }

    void search(const QList<QHelpSearchQuery> &queryList)
    {
        if (helpEngine.isNull())
            return;

        if (!QFile::exists(QFileInfo(helpEngine->collectionFile()).path()))
            return;

        if (!indexReader) {
            indexReader = new QHelpSearchIndexReader();

            connect(indexReader, SIGNAL(searchingStarted()), this, SIGNAL(searchingStarted()));
            connect(indexReader, SIGNAL(searchingFinished(int)), this, SIGNAL(searchingFinished(int)));
        }

        if (indexReader) {
            m_queryList = queryList;
            indexReader->cancelSearching();
            indexReader->search(helpEngine->collectionFile(), indexFilesFolder(), queryList);
        }
    }

    void cancelSearching()
    {
        if (indexReader)
            indexReader->cancelSearching();
    }

    QString indexFilesFolder() const
    {
        QString indexFilesFolder = QLatin1String(".fulltextsearch");
        if (helpEngine && !helpEngine->collectionFile().isEmpty()) {
            QFileInfo fi(helpEngine->collectionFile());
            indexFilesFolder = fi.absolutePath() + QDir::separator()
                + QLatin1Char('.')
                + fi.fileName().left(fi.fileName().lastIndexOf(QLatin1String(".qhc")));
        }
        return indexFilesFolder;
    }

private slots:
    void optimizeIndex()
    {
#if defined(QT_CLUCENE_SUPPORT)
        if (indexWriter && !helpEngine.isNull()) {
            indexWriter->optimizeIndex();            
        }
#endif
    }

private:
    friend class QHelpSearchEngine;

    QHelpSearchQueryWidget *queryWidget;
    QHelpSearchResultWidget *resultWidget;

    QHelpSearchIndexReader *indexReader;
    QHelpSearchIndexWriter *indexWriter;

    QPointer<QHelpEngineCore> helpEngine;
    QList<QHelpSearchEngine::SearchHit> hitList;

    QList<QHelpSearchQuery> m_queryList;
};

#include "qhelpsearchengine.moc"


/*!
    \class QHelpSearchQuery
    \since 4.4
    \inmodule QtHelp
    \brief The QHelpSearchQuery class contains the field name and the associated
    search term

    The QHelpSearchQuery class contains the field name and the associated search
    term. Depending on the field the search term might get split up into seperate
    terms to be parsed differently by the search engine.

    \sa QHelpSearchQueryWidget
*/

/*!
    \fn QHelpSearchQuery::QHelpSearchQuery()

    Constructs a new empty QHelpSearchQuery.
*/

/*!
    \fn QHelpSearchQuery::QHelpSearchQuery(FieldName field, const QStringList &wordList)

    Constructs a new QHelpSearchQuery and initializes it with the given \a field and \a wordList.
*/

/*!
    \enum QHelpSearchQuery::FieldName
    This enum type specifies the field names that are handled by the search engine.

    \value DEFAULT  the default field provided by the search widget, several terms should be
                    splitted and stored in the wordlist except search terms enclosed in quotes.
    \value FUZZY    a field only provided in use with clucene. Terms should be split in seperate
                    words and passed to the search engine.
    \value WITHOUT  a field only provided in use with clucene. Terms should be split in seperate
                    words and passed to the search engine.
    \value PHRASE   a field only provided in use with clucene. Terms should not be split in seperate
                    words.
    \value ALL      a field only provided in use with clucene. Terms should be split in seperate
                    words and passed to the search engine
    \value ATLEAST  a field only provided in use with clucene. Terms should be split in seperate
                    words and passed to the search engine
*/

/*!
    \class QHelpSearchEngine
    \since 4.4
    \inmodule QtHelp
    \brief The QHelpSearchEngine class provides access to widgets reusable
    to integrate fulltext search as well as to index and search documentation.

    Before the search engine can be used, one has to instantiate at least a
    QHelpEngineCore object that needs to be passed to the search engines constructor.