/* ============================================================
* QupZilla - WebKit based browser
* Copyright (C) 2010-2014  David Rosca <nowrep@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program.  If not, see <http://www.gnu.org/licenses/>.
* ============================================================ */
/****************************************************************************
 **
 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
 ** All rights reserved.
 ** Contact: Nokia Corporation (qt-info@nokia.com)
 **
 ** This file is part of the examples of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:BSD$
 ** You may use this file under the terms of the BSD license as follows:
 **
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 ** modification, are permitted provided that the following conditions are
 ** met:
 **   * Redistributions of source code must retain the above copyright
 **     notice, this list of conditions and the following disclaimer.
 **   * Redistributions in binary form must reproduce the above copyright
 **     notice, this list of conditions and the following disclaimer in
 **     the documentation and/or other materials provided with the
 **     distribution.
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 **     the names of its contributors may be used to endorse or promote
 **     products derived from this software without specific prior written
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#include "htmlhighlighter.h"

HtmlHighlighter::HtmlHighlighter(QTextDocument* parent)
    : QSyntaxHighlighter(parent)
{
    HighlightingRule rule;

    // tags: <tag1> </tag1>
    tagFormat.setForeground(Qt::darkBlue);
    tagFormat.setFontWeight(QFont::Bold);
    QStringList keywordPatterns;
    keywordPatterns << "</?([A-Za-z:0-9]{1,20})/?(>| )?" << ">" << "(<!DOCTYPE html>|<!DOCTYPE html PUBLIC)";
    foreach (const QString &pattern, keywordPatterns) {
        rule.pattern = QzRegExp(pattern);
        rule.format = tagFormat;
        highlightingRules.append(rule);
    }

    // options: <tag option1="" option2="">
    tagOptionsFormat.setForeground(Qt::black);
    tagOptionsFormat.setFontWeight(QFont::Bold);
    rule.pattern = QzRegExp("(\\S{2,20})=\"");
    rule.format = tagOptionsFormat;
    highlightingRules.append(rule);

    // " " strings
    quotationFormat.setForeground(Qt::darkGreen);
    QzRegExp rx("\".*\"");
    rx.setMinimal(true);
    rule.pattern = rx;
    rule.format = quotationFormat;
    highlightingRules.append(rule);

    // <!-- --> comments
    multiLineCommentFormat.setForeground(Qt::gray);
    commentStartExpression = QzRegExp("<!--");
    commentEndExpression = QzRegExp("-->");
}

void HtmlHighlighter::highlightBlock(const QString &text)
{
    foreach (const HighlightingRule &rule, highlightingRules) {
        QzRegExp expression(rule.pattern);
        int index = expression.indexIn(text);
        while (index >= 0) {
            int length = expression.matchedLength();
            setFormat(index, length, rule.format);
            index = expression.indexIn(text, index + length);
        }
    }

    // Highlighting multi-line comments
    setCurrentBlockState(0);

    int startIndex = 0;
    if (previousBlockState() != 1) {
        startIndex = commentStartExpression.indexIn(text);
    }

    while (startIndex >= 0) {
        int endIndex = commentEndExpression.indexIn(text, startIndex);
        int commentLength;
        if (endIndex == -1) {
            setCurrentBlockState(1);
            commentLength = text.length() - startIndex;
        }
        else {
            commentLength = endIndex - startIndex
                            + commentEndExpression.matchedLength();
        }
        setFormat(startIndex, commentLength, multiLineCommentFormat);
        startIndex = commentStartExpression.indexIn(text, startIndex + commentLength);
    }
}
