text: #include "qrcodedialog.h"
  #include "ui_qrcodedialog.h"
  
  #include "bitcoinunits.h"
  #include "guiconstants.h"
  #include "guiutil.h"
  #include "optionsmodel.h"
  
  #include <QPixmap>
  #include <QUrl>
  
  #include <qrencode.h>
  
  QRCodeDialog::QRCodeDialog(const QString &addr, const QString &label, bool enableReq, QWidget *parent) :
      QDialog(parent),
      ui(new Ui::QRCodeDialog),
      model(0),
      address(addr)
  {
      ui->setupUi(this);
  
      setWindowTitle(QString("%1").arg(address));
  
      ui->chkReqPayment->setVisible(enableReq);
      ui->lblAmount->setVisible(enableReq);
      ui->lnReqAmount->setVisible(enableReq);
  
      ui->lnLabel->setText(label);
  
      ui->btnSaveAs->setEnabled(false);
  
      genCode();
  }
  
  QRCodeDialog::~QRCodeDialog()
  {
      delete ui;
  }
  
  void QRCodeDialog::setModel(OptionsModel *model)
  {
      this->model = model;
  
      if (model)
          connect(model, SIGNAL(displayUnitChanged(int)), this, SLOT(updateDisplayUnit()));
  
      // update the display unit, to not use the default ("BTC")
      updateDisplayUnit();
  }
  
  void QRCodeDialog::genCode()
  {
      QString uri = getURI();
  
      if (uri != "")
      {
          ui->lblQRCode->setText("");
  
          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;
          }
          myImage = QImage(code->width + 8, code->width + 8, QImage::Format_RGB32);
          myImage.fill(0xffffff);
          unsigned char *p = code->data;
          for (int y = 0; y < code->width; y++)
          {
              for (int x = 0; x < code->width; x++)
              {
                  myImage.setPixel(x + 4, y + 4, ((*p & 1) ? 0x0 : 0xffffff));
                  p++;
              }
          }
          QRcode_free(code);
  
          ui->lblQRCode->setPixmap(QPixmap::fromImage(myImage).scaled(300, 300));
  
          ui->outUri->setPlainText(uri);
      }
  }
  
  QString QRCodeDialog::getURI()
  {
      QString ret = QString("valuecoin:%1").arg(address);
      int paramCount = 0;
  
      ui->outUri->clear();
  
      if (ui->chkReqPayment->isChecked())
      {
          if (ui->lnReqAmount->validate())
          {
              // even if we allow a non BTC unit input in lnReqAmount, we generate the URI with BTC as unit (as defined in BIP21)
              ret += QString("?amount=%1").arg(BitcoinUnits::format(BitcoinUnits::BTC, ui->lnReqAmount->value()));
              paramCount++;
          }
          else
          {
              ui->btnSaveAs->setEnabled(false);
              ui->lblQRCode->setText(tr("The entered amount is invalid, please check."));
              return QString("");
          }
      }
  
      if (!ui->lnLabel->text().isEmpty())
      {
          QString lbl(QUrl::toPercentEncoding(ui->lnLabel->text()));
          ret += QString("%1label=%2").arg(paramCount == 0 ? "?" : "&").arg(lbl);
          paramCount++;
      }
  
      if (!ui->lnMessage->text().isEmpty())
      {
          QString msg(QUrl::toPercentEncoding(ui->lnMessage->text()));
          ret += QString("%1message=%2").arg(paramCount == 0 ? "?" : "&").arg(msg);
          paramCount++;
      }
  
      // limit URI length to prevent a DoS against the QR-Code dialog
      if (ret.length() > MAX_URI_LENGTH)
      {
          ui->btnSaveAs->setEnabled(false);
          ui->lblQRCode->setText(tr("Resulting URI too long, try to reduce the text for label / message."));
          return QString("");
      }
  
      ui->btnSaveAs->setEnabled(true);
      return ret;
  }
  
  void QRCodeDialog::on_lnReqAmount_textChanged()
  {
      genCode();
  }
  
  void QRCodeDialog::on_lnLabel_textChanged()
  {
      genCode();
  }
  
  void QRCodeDialog::on_lnMessage_textChanged()
  {
      genCode();
  }
  
  void QRCodeDialog::on_btnSaveAs_clicked()
  {
      QString fn = GUIUtil::getSaveFileName(this, tr("Save QR Code"), QString(), tr("PNG Images (*.png)"));
      if (!fn.isEmpty())
          myImage.scaled(EXPORT_IMAGE_SIZE, EXPORT_IMAGE_SIZE).save(fn);
  }
  
  void QRCodeDialog::on_chkReqPayment_toggled(bool fChecked)
  {
      if (!fChecked)
          // if chkReqPayment is not active, don't display lnReqAmount as invalid
          ui->lnReqAmount->setValid(true);
  
      genCode();
  }
  
  void QRCodeDialog::updateDisplayUnit()
  {
      if (model)
      {
          // Update lnReqAmount with the current unit
          ui->lnReqAmount->setDisplayUnit(model->getDisplayUnit());
      }
  }
  