KSyntaxHighlighting

 /*
     SPDX-FileCopyrightText: 2016 Volker Krause <[email protected]>
     SPDX-FileCopyrightText: 2018 Christoph Cullmann <[email protected]>
  
     SPDX-License-Identifier: MIT
 */
  
 #include "htmlhighlighter.h"
 #include "definition.h"
 #include "format.h"
 #include "ksyntaxhighlighting_logging.h"
 #include "state.h"
 #include "theme.h"
  
 #include <QFile>
 #include <QFileInfo>
 #include <QTextStream>
 #include <QVarLengthArray>
  
 using namespace KSyntaxHighlighting;
  
 class KSyntaxHighlighting::HtmlHighlighterPrivate
 {
 public:
     std::unique_ptr<QTextStream> out;
     std::unique_ptr<QFile> file;
     QString currentLine;
 };
  
 HtmlHighlighter::HtmlHighlighter()
     : d(new HtmlHighlighterPrivate())
 {
 }
  
 HtmlHighlighter::~HtmlHighlighter()
 {
 }
  
 void HtmlHighlighter::setOutputFile(const QString &fileName)
 {
     d->file.reset(new QFile(fileName));
     if (!d->file->open(QFile::WriteOnly | QFile::Truncate)) {
         qCWarning(Log) << "Failed to open output file" << fileName << ":" << d->file->errorString();
         return;
     }
     d->out.reset(new QTextStream(d->file.get()));
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
     d->out->setEncoding(QStringConverter::Utf8);
 #else
     d->out->setCodec("UTF-8");
 #endif
 }
  
 void HtmlHighlighter::setOutputFile(FILE *fileHandle)
 {
     d->out.reset(new QTextStream(fileHandle, QIODevice::WriteOnly));
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
     d->out->setEncoding(QStringConverter::Utf8);
 #else
     d->out->setCodec("UTF-8");
 #endif
 }
  
 void HtmlHighlighter::highlightFile(const QString &fileName, const QString &title)
 {
     QFileInfo fi(fileName);
     QFile f(fileName);
     if (!f.open(QFile::ReadOnly)) {
         qCWarning(Log) << "Failed to open input file" << fileName << ":" << f.errorString();
         return;
     }
  
     if (title.isEmpty()) {
         highlightData(&f, fi.fileName());
     } else {
         highlightData(&f, title);
     }
 }
  
 /**
  * @brief toHtmlRgba
  * Converts QColor -> rgba(r, g, b, a) if there is an alpha channel
  * otherwise it will just return the hexcode. This is because QColor
  * outputs #AARRGGBB, whereas browser support #RRGGBBAA.
  *
  * @param color
  * @return
  */
 static QString toHtmlRgbaString(const QColor &color)
 {
     if (color.alpha() == 0xFF) {
         return color.name();
     }
  
     QString rgba = QStringLiteral("rgba(");
     rgba.append(QString::number(color.red()));
     rgba.append(QLatin1Char(','));
     rgba.append(QString::number(color.green()));
     rgba.append(QLatin1Char(','));
     rgba.append(QString::number(color.blue()));
     rgba.append(QLatin1Char(','));
     // this must be alphaF
     rgba.append(QString::number(color.alphaF()));
     rgba.append(QLatin1Char(')'));
     return rgba;
 }
  
 void HtmlHighlighter::highlightData(QIODevice *dev, const QString &title)
 {
     if (!d->out) {
         qCWarning(Log) << "No output stream defined!";
         return;
     }
  
     QString htmlTitle;
     if (title.isEmpty()) {
         htmlTitle = QStringLiteral("Kate Syntax Highlighter");
     } else {
         htmlTitle = title.toHtmlEscaped();
     }
  
     State state;
     *d->out << "<!DOCTYPE html>\n";
     *d->out << "<html><head>\n";
     *d->out << "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\"/>\n";
     *d->out << "<title>" << htmlTitle << "</title>\n";
     *d->out << "<meta name=\"generator\" content=\"KF5::SyntaxHighlighting - Definition (" << definition().name() << ") - Theme (" << theme().name()
             << ")\"/>\n";
     *d->out << "</head><body";
     *d->out << " style=\"background-color:" << toHtmlRgbaString(QColor::fromRgba(theme().editorColor(Theme::BackgroundColor)));
     if (theme().textColor(Theme::Normal)) {
         *d->out << ";color:" << toHtmlRgbaString(QColor::fromRgba(theme().textColor(Theme::Normal)));
     }
     *d->out << "\"><pre>\n";
  
     QTextStream in(dev);
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
     in.setCodec("UTF-8");
 #endif
     while (in.readLineInto(&d->currentLine)) {
         state = highlightLine(d->currentLine, state);
         *d->out << "\n";
     }
  
     *d->out << "</pre></body></html>\n";
     d->out->flush();
  
     d->out.reset();
     d->file.reset();
 }
  
 void HtmlHighlighter::applyFormat(int offset, int length, const Format &format)
 {
     if (length == 0) {
         return;
     }
  
     // collect potential output, cheaper than thinking about "is there any?"
     QVarLengthArray<QString, 16> formatOutput;
     if (format.hasTextColor(theme())) {
         formatOutput << QStringLiteral("color:") << toHtmlRgbaString(format.textColor(theme())) << QStringLiteral(";");
     }
     if (format.hasBackgroundColor(theme())) {
         formatOutput << QStringLiteral("background-color:") << toHtmlRgbaString(format.backgroundColor(theme())) << QStringLiteral(";");
     }
     if (format.isBold(theme())) {
         formatOutput << QStringLiteral("font-weight:bold;");
     }
     if (format.isItalic(theme())) {
         formatOutput << QStringLiteral("font-style:italic;");
     }
     if (format.isUnderline(theme())) {
         formatOutput << QStringLiteral("text-decoration:underline;");
     }
     if (format.isStrikeThrough(theme())) {
         formatOutput << QStringLiteral("text-decoration:line-through;");
     }
  
     if (!formatOutput.isEmpty()) {
         *d->out << "<span style=\"";
         for (const auto &out : std::as_const(formatOutput)) {
             *d->out << out;
         }
         *d->out << "\">";
     }
  
     *d->out << d->currentLine.mid(offset, length).toHtmlEscaped();
  
     if (!formatOutput.isEmpty()) {
         *d->out << "</span>";
     }
 }