text: // Copyright (c) 2011-2016 The Bitcoin Core developers
  // Copyright (c) 2017 The Bitcoin developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #include <receiverequestdialog.h>
  #include <ui_receiverequestdialog.h>
  
  #include <bitcoinunits.h>
  #include <config.h>
  #include <guiconstants.h>
  #include <guiutil.h>
  #include <optionsmodel.h>
  #include <walletmodel.h>
  
  #include <QClipboard>
  #include <QDrag>
  #include <QMenu>
  #include <QMimeData>
  #include <QMouseEvent>
  #include <QPixmap>
  
  #if defined(HAVE_CONFIG_H)
  #include <config/bitcoin-config.h> /* for USE_QRCODE */
  #endif
  
  #ifdef USE_QRCODE
  #include <qrencode.h>
  #endif
  
  QRImageWidget::QRImageWidget(QWidget *parent) : QLabel(parent), contextMenu(nullptr) {
      contextMenu = new QMenu(this);
      QAction *saveImageAction = new QAction(tr("&Save Image..."), this);
      connect(saveImageAction, &QAction::triggered, this,
              &QRImageWidget::saveImage);
      contextMenu->addAction(saveImageAction);
      QAction *copyImageAction = new QAction(tr("&Copy Image"), this);
      connect(copyImageAction, &QAction::triggered, this,
              &QRImageWidget::copyImage);
      contextMenu->addAction(copyImageAction);
  }
  
  QImage QRImageWidget::exportImage() {
  #if QT_VERSION >= QT_VERSION_CHECK(5,15,0)
    if (!pixmap(Qt::ReturnByValue)) return QImage();
    return pixmap(Qt::ReturnByValue).toImage();
  #else
    if (!pixmap()) return QImage();
    return pixmap()->toImage();
  #endif
  }
  
  void QRImageWidget::mousePressEvent(QMouseEvent *event) {
  #if QT_VERSION >= QT_VERSION_CHECK(5,15,0)
      if (event->button() == Qt::LeftButton && pixmap(Qt::ReturnByValue).isNull()) {
  #else
      if (event->button() == Qt::LeftButton && pixmap()) {
  #endif
          event->accept();
          QMimeData *mimeData = new QMimeData;
          mimeData->setImageData(exportImage());
  
          QDrag *drag = new QDrag(this);
          drag->setMimeData(mimeData);
          drag->exec();
      } else {
          QLabel::mousePressEvent(event);
      }
  }
  
  void QRImageWidget::saveImage() {
  #if QT_VERSION >= QT_VERSION_CHECK(5,15,0)
      if (!pixmap(Qt::ReturnByValue)) return;
  #else
      if (!pixmap()) return;
  #endif
      QString fn = GUIUtil::getSaveFileName(this, tr("Save QR Code"), QString(),
                                            tr("PNG Image (*.png)"), nullptr);
      if (!fn.isEmpty()) {
          exportImage().save(fn);
      }
  }
  
  void QRImageWidget::copyImage() {
  #if QT_VERSION >= QT_VERSION_CHECK(5,15,0)
      if (!pixmap(Qt::ReturnByValue)) return;
  #else
      if (!pixmap()) return;
  #endif
      QApplication::clipboard()->setImage(exportImage());
  }
  
  void QRImageWidget::contextMenuEvent(QContextMenuEvent *event) {
  #if QT_VERSION >= QT_VERSION_CHECK(5,15,0)
      if (!pixmap(Qt::ReturnByValue)) return;
  #else
      if (!pixmap()) return;
  #endif
      contextMenu->exec(event->globalPos());
  }
  
  ReceiveRequestDialog::ReceiveRequestDialog(const Config *configIn,
                                             QWidget *parent)
      : QDialog(parent), ui(new Ui::ReceiveRequestDialog), model(nullptr),
        config(configIn) {
      ui->setupUi(this);
  
  #ifndef USE_QRCODE
      ui->btnSaveAs->setVisible(false);
      ui->lblQRCode->setVisible(false);
  #endif
  
      connect(ui->btnSaveAs, &QPushButton::clicked, ui->lblQRCode,
              &QRImageWidget::saveImage);
  }
  
  ReceiveRequestDialog::~ReceiveRequestDialog() {
      delete ui;
  }
  
  void ReceiveRequestDialog::setModel(WalletModel *_model) {
      this->model = _model;
  
      if (_model) {
          connect(_model->getOptionsModel(), &OptionsModel::displayUnitChanged,
                  this, &ReceiveRequestDialog::update);
      }
  
      // update the display unit if necessary
      update();
  }
  
  void ReceiveRequestDialog::setInfo(const SendCoinsRecipient &_info) {
      this->info = _info;
      // Display addresses with currently configured encoding.
      this->info.address =
          GUIUtil::convertToConfiguredAddressFormat(*config, this->info.address);
      update();
  }
  
  void ReceiveRequestDialog::update() {
      if (!model) return;
      QString target = info.label;
      if (target.isEmpty()) target = info.address;
      setWindowTitle(tr("Request payment to %1").arg(target));
  
      QString uri = GUIUtil::formatBitcoinURI(*config, info);
      ui->btnSaveAs->setEnabled(false);
      QString html;
      html += "<html><font face='verdana, arial, helvetica, sans-serif'>";
      html += "<b>" + tr("Payment information") + "</b><br>";
      html += "<b>" + tr("URI") + "</b>: ";
      html += "<a href=\"" + uri + "\">" + GUIUtil::HtmlEscape(uri) + "</a><br>";
      html += "<b>" + tr("Address") +
              "</b>: " + GUIUtil::HtmlEscape(info.address) + "<br>";
      if (info.amount != Amount::zero())
          html += "<b>" + tr("Amount") + "</b>: " +
                  BitcoinUnits::formatHtmlWithUnit(
                      model->getOptionsModel()->getDisplayUnit(), info.amount) +
                  "<br>";
      if (!info.label.isEmpty())
          html += "<b>" + tr("Label") +
                  "</b>: " + GUIUtil::HtmlEscape(info.label) + "<br>";
      if (!info.message.isEmpty())
          html += "<b>" + tr("Message") +
                  "</b>: " + GUIUtil::HtmlEscape(info.message) + "<br>";
      if (model->isMultiwallet()) {
          html += "<b>" + tr("Wallet") +
                  "</b>: " + GUIUtil::HtmlEscape(model->getWalletName()) + "<br>";
      }
      ui->outUri->setText(html);
  
  #ifdef USE_QRCODE
      int fontSize = 10;
  
      ui->lblQRCode->setText("");
      if (!uri.isEmpty()) {
          // limit URI length
          if (uri.length() > MAX_URI_LENGTH) {
              ui->lblQRCode->setText(tr("Resulting URI too long, try to reduce "
                                        "the text for label / message."));
          } else {
              QRcode *code = QRcode_encodeString(uri.toUtf8().constData(), 0,
                                                 QR_ECLEVEL_L, QR_MODE_8, 1);
              if (!code) {
                  ui->lblQRCode->setText(tr("Error encoding URI into QR Code."));
                  return;
              }
              QImage qrImage =
                  QImage(code->width + 8, code->width + 8, QImage::Format_RGB32);
              qrImage.fill(0xffffff);
              uint8_t *p = code->data;
              for (int y = 0; y < code->width; y++) {
                  for (int x = 0; x < code->width; x++) {
                      qrImage.setPixel(x + 4, y + 4, ((*p & 1) ? 0x0 : 0xffffff));
                      p++;
                  }
              }
              QRcode_free(code);
  
              QImage qrAddrImage =
                  QImage(QR_IMAGE_SIZE, QR_IMAGE_SIZE + 20, QImage::Format_RGB32);
              qrAddrImage.fill(0xffffff);
              QPainter painter(&qrAddrImage);
              painter.drawImage(0, 0,
                                qrImage.scaled(QR_IMAGE_SIZE, QR_IMAGE_SIZE));
              QFont font = GUIUtil::fixedPitchFont();
              font.setPixelSize(fontSize);
              painter.setFont(font);
              QRect paddedRect = qrAddrImage.rect();
              paddedRect.setHeight(QR_IMAGE_SIZE + 12);
              painter.drawText(paddedRect, Qt::AlignBottom | Qt::AlignCenter,
                               info.address);
              painter.end();
  
              ui->lblQRCode->setPixmap(QPixmap::fromImage(qrAddrImage));
              ui->btnSaveAs->setEnabled(true);
          }
      }
  #endif
  }
  
  void ReceiveRequestDialog::on_btnCopyURI_clicked() {
      GUIUtil::setClipboard(GUIUtil::formatBitcoinURI(*config, info));
  }
  
  void ReceiveRequestDialog::on_btnCopyAddress_clicked() {
      GUIUtil::setClipboard(info.address);
  }
  