LoadImageFromUrl.cpp

/******************************************************************************************************
 * (C) 2014 markummitchell@github.com. This file is part of Engauge Digitizer, which is released      *
 * under GNU General Public License version 2 (GPLv2) or (at your option) any later version. See file *
 * LICENSE or go to gnu.org/licenses for details. Distribution requires prior written permission.     *
 ******************************************************************************************************/
 
#include "LoadImageFromUrl.h"
#include "Logger.h"
#include "MainWindow.h"
#include <QFileInfo>
#include <QMessageBox>
#include <QtNetwork/QNetworkReply>
#include <QUrl>
#include "Version.h"
 
LoadImageFromUrl::LoadImageFromUrl (MainWindow &mainWindow) :
  m_mainWindow (mainWindow),
  m_http (this),
  m_reply (0),
  m_buffer (0)
{
  connect (this, SIGNAL (signalImportImage (QString, QImage)), &m_mainWindow, SLOT (slotFileImportImage (QString, QImage)));
}
 
LoadImageFromUrl::~LoadImageFromUrl ()
{
  deallocate ();
}
 
void LoadImageFromUrl::deallocate ()
{
  if (m_reply != 0) {
    delete m_reply;
    m_reply = 0;
  }
 
  if (m_buffer != 0) {
    delete m_buffer;
    m_buffer = 0;
  }
}
 
void LoadImageFromUrl::slotFinished ()
{
  // Download has just finished
 
  QString urlWithoutScheme = m_url.toString (QUrl::RemoveScheme);
 
  // Import
  QImage image;
  if (image.loadFromData (*m_buffer)) {
 
    emit signalImportImage (urlWithoutScheme,
                            image);
  } else {
 
    // Images embedded in web pages produce html in m_buffer. No easy way to fix that. Even
    // gimp fails in the same situations so we just show an error
 
    QString message;
    QTextStream str (&message);
 
    str << tr ("Unable to download image from") << " " << urlWithoutScheme;
 
    QMessageBox::critical (&m_mainWindow,
                           engaugeWindowTitle(),
                           message,
                           QMessageBox::Ok);
  }
}
 
void LoadImageFromUrl::startLoadImage (const QUrl &url)
{
  LOG4CPP_INFO_S ((*mainCat)) << "LoadImageFromUrl::startLoadImage url=" << url.toString ().toLatin1 ().data ();
 
  m_url = url;
  if (url.isLocalFile ()) {
 
    QFileInfo fileInfo (url.toLocalFile ());
 
    // Load local file. This is done synchronously
    QImage image;
    if (image.load (url.toLocalFile ())) {
 
      emit signalImportImage (fileInfo.fileName (),
                              image);
 
    } else {
 
      // Probably a bad file type
 
      QString message;
      QTextStream str (&message);
 
      str << tr ("Unable to load image from") << " " << url.toLocalFile ();
 
      QMessageBox::critical (&m_mainWindow,
                             engaugeWindowTitle(),
                             message,
                             QMessageBox::Ok);
    }
 
  } else {
 
    // Asynchronous read from url
    deallocate ();
    m_buffer = new QByteArray;
    QNetworkRequest request (url);
    m_reply = m_http.get (request);
 
    connect (m_reply, SIGNAL (readyRead()), this, SLOT (slotReadData()));
    connect (m_reply, SIGNAL (finished ()), this, SLOT (slotFinished ()));
  }
}
 
void LoadImageFromUrl::slotReadData ()
{
  *m_buffer += m_reply->readAll ();
}