highlighter.cpp

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#include "dbe/highlighter.hpp"
#include <QtGui>
#include <QMutexLocker>
 
//using namespace daq::QTUtils;
Highlighter::Highlighter(QTextDocument *parent)
        : QSyntaxHighlighter(parent)
{
    mutex = new QMutex();
}

void Highlighter::highlightBlock(const QString &text)
{
    QMutexLocker locker(mutex);
    
    /*
     * check if we have formatted this text before
     * If so there is no need to run regexp again and we can simply reapply the cached formatting.
     * Remember to clear the cache if new rules are added after it has been filled (not likely)
     */
    uint hash = qHash(text);
    if(cache.contains(hash)) 
    {
        FormatCache form;
        foreach(form,cache.value(hash)){
            for(int i =0; i < form.indexes.size();i++)
            {
                setFormat(form.indexes.at(i), form.lengths.at(i), form.rule.format);
            }
        }
    }
    else
    {
        QList<FormatCache> forms; //list of all formatting being done
        foreach (HighlightingRule rule, highlightingRules)
        {
            FormatCache form;
            form.rule = rule; //store the rule 
            QRegExp expression(rule.pattern);
            int index = text.indexOf(expression);
            int length;
            while (index >= 0)
            {
 
                length = expression.matchedLength();
                form.indexes.append(index); //store index 
                form.lengths.append(length);//store length
                setFormat(index, length, rule.format);
                index = text.indexOf(expression, index + length);
            }
            forms.append(form); //append this formatting (rule, indexes and lengths) to the list
        }
        cache.insert(hash,forms);//store list in cache
 
    }
    if(!highlightAllReg.isEmpty())
    {
        int index = text.indexOf(highlightAllReg);
        while (index >= 0)
        {
            int length = highlightAllReg.matchedLength();
            QTextCharFormat format;
            format.setBackground(Qt::yellow);
            setFormat(index, length, format);
            index = text.indexOf(highlightAllReg, index + length);
        }
    }
   
}