#include <QApplication>
#include <QCoreApplication>

#include <QWebEngineView>
#include <QWebEngineSettings>

#include <QPrinter>
#include <QPrintDialog>
#include <QDebug>
#include <QAction>
#include <QPageLayout>
#include <QFile>

int main(int argc, char *argv[])
{
  QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
  QApplication a(argc, argv);

  QPrinter printer;
  printer.setResolution(QPrinter::HighResolution);

  QWebEngineView* viewer = new QWebEngineView();
  viewer->settings()->setAttribute(QWebEngineSettings::PrintElementBackgrounds, true);

  QAction * act = new QAction("Print", viewer);
  act->setShortcut(Qt::CTRL + Qt::Key_P);
  viewer->addAction(act);

  static int fileCounter = 0;

  QPageLayout layout;
  layout.setPageSize(QPageSize(QPageSize::A4));
  layout.setOrientation(QPageLayout::Landscape);
  layout.setMargins(QMarginsF(0, 0, 0, 0));

  int which = 0;
  if (which == 0) {
      // Print to QPrinter.
      QObject::connect(act, &QAction::triggered, [&]() {
        QPrintDialog printDialog(&printer);
        if (printDialog.exec() == QDialog::Accepted) {
          printer.setPaperSize(QPrinter::A5);
          printer.setPageOrientation(QPageLayout::Landscape);
          printer.setPageMargins(0, 0, 0, 0, QPrinter::Millimeter);
          printer.setFullPage(false);

          viewer->page()->print(&printer, [&](bool result) {
              qDebug() << "QPrinter callback. Result:" << result;
          });
        }
      });
  } else if (which == 1) {
      // Print to PDF file path.
      QObject::connect(act, &QAction::triggered, [&]() {
          ++fileCounter;
          viewer->page()->printToPdf(QString("E:\\a%1.pdf").arg(fileCounter), layout);
          qDebug() << "Called printToPdf with file path.";
      });
  } else if (which == 2) {
      // Print to PDF in QByteArray, and then write the contents with QFile.
      QObject::connect(act, &QAction::triggered, [&]() {
          ++fileCounter;
          viewer->page()->printToPdf([](const QByteArray& content){
              QFile f(QString("E:\\a%1.pdf").arg(fileCounter));
              if (!f.open(QIODevice::WriteOnly))
                  return;
              f.write(content);
              f.close();
              qDebug() << "pdfPrintingFinished QByteArray finished";
          }, layout);
          qDebug() << "Called printToPdf with QByteArray";
      });
  }

  viewer->load(QUrl("https://www.google.com"));
  viewer->show();

  QObject::connect(viewer->page(), &QWebEnginePage::pdfPrintingFinished,
                   [&](const QString &filePath, bool ok){
      qDebug() << "pdfPrintingFinished filePath" << filePath << "ok" << ok;
  });

  int result = a.exec();
  delete viewer;
  return result;
}