1 files changed, 141 insertions, 0 deletions
diff --git a/src/qt/qrimagewidget.cpp b/src/qt/qrimagewidget.cpp
new file mode 100644
index 0000000000..bf1baf5470
--- /dev/null
+++ b/src/qt/qrimagewidget.cpp
@@ -0,0 +1,141 @@
+// Copyright (c) 2011-2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <qt/qrimagewidget.h>
+
+#include <qt/guiutil.h>
+
+#include <QApplication>
+#include <QClipboard>
+#include <QDrag>
+#include <QMenu>
+#include <QMimeData>
+#include <QMouseEvent>
+#include <QPainter>
+
+#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);
+}
+
+bool QRImageWidget::setQR(const QString& data, const QString& text)
+{
+#ifdef USE_QRCODE
+    setText("");
+    if (data.isEmpty()) return false;
+
+    // limit length
+    if (data.length() > MAX_URI_LENGTH) {
+        setText(tr("Resulting URI too long, try to reduce the text for label / message."));
+        return false;
+    }
+
+    QRcode *code = QRcode_encodeString(data.toUtf8().constData(), 0, QR_ECLEVEL_L, QR_MODE_8, 1);
+
+    if (!code) {
+        setText(tr("Error encoding URI into QR Code."));
+        return false;
+    }
+
+    QImage qrImage = QImage(code->width + 8, code->width + 8, QImage::Format_RGB32);
+    qrImage.fill(0xffffff);
+    unsigned char *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 + (text.isEmpty() ? 0 : 20), QImage::Format_RGB32);
+    qrAddrImage.fill(0xffffff);
+    QPainter painter(&qrAddrImage);
+    painter.drawImage(0, 0, qrImage.scaled(QR_IMAGE_SIZE, QR_IMAGE_SIZE));
+
+    if (!text.isEmpty()) {
+        QFont font = GUIUtil::fixedPitchFont();
+        QRect paddedRect = qrAddrImage.rect();
+
+        // calculate ideal font size
+        qreal font_size = GUIUtil::calculateIdealFontSize(paddedRect.width() - 20, text, font);
+        font.setPointSizeF(font_size);
+
+        painter.setFont(font);
+        paddedRect.setHeight(QR_IMAGE_SIZE+12);
+        painter.drawText(paddedRect, Qt::AlignBottom|Qt::AlignCenter, text);
+    }
+
+    painter.end();
+    setPixmap(QPixmap::fromImage(qrAddrImage));
+
+    return true;
+#else
+    setText(tr("QR code support not available."));
+    return false;
+#endif
+}
+
+QImage QRImageWidget::exportImage()
+{
+    if(!pixmap())
+        return QImage();
+    return pixmap()->toImage();
+}
+
+void QRImageWidget::mousePressEvent(QMouseEvent *event)
+{
+    if(event->button() == Qt::LeftButton && pixmap())
+    {
+        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(!pixmap())
+        return;
+    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(!pixmap())
+        return;
+    QApplication::clipboard()->setImage(exportImage());
+}
+
+void QRImageWidget::contextMenuEvent(QContextMenuEvent *event)
+{
+    if(!pixmap())
+        return;
+    contextMenu->exec(event->globalPos());
+}