File indexing completed on 2024-05-12 15:50:10

 #include <QDomDocument>
 #include <QEventLoop>
 #include <QFile>
 #include <QNetworkAccessManager>
 #include <QNetworkReply>
 #include <QNetworkRequest>
 #include <QThread>
 
 #include <ThreadWeaver/Exception>
 #include <ThreadWeaver/ThreadWeaver>
 
 #include "MainWidget.h"
 #include "ViewController.h"
 
 ViewController::ViewController(MainWidget *mainwidget)
     : QObject() // no parent
     , m_apiPostUrl(QStringLiteral("http://fickedinger.tumblr.com/api/read?id=94635924143"))
 //@@snippet_begin(hellointernet-sequence)
 {
     connect(this, SIGNAL(setImage(QImage)), mainwidget, SLOT(setImage(QImage)));
     connect(this, SIGNAL(setCaption(QString)), mainwidget, SLOT(setCaption(QString)));
     connect(this, SIGNAL(setStatus(QString)), mainwidget, SLOT(setStatus(QString)));
 
     using namespace ThreadWeaver;
     auto s = new Sequence;
     *s << make_job([=]() {
         loadPlaceholderFromResource();
     }) << make_job([=]() {
         loadPostFromTumblr();
     }) << make_job([=]() {
         loadImageFromTumblr();
     });
     stream() << s;
 }
 //@@snippet_end
 
 ViewController::~ViewController()
 {
     ThreadWeaver::Queue::instance()->finish();
 }
 
 //@@snippet_begin(hellointernet-loadresource)
 void ViewController::loadPlaceholderFromResource()
 {
     QThread::msleep(500);
     showResourceImage("IMG_20140813_004131.png");
     Q_EMIT setStatus(tr("Downloading post..."));
 }
 //@@snippet_end
 
 //@@snippet_begin(hellointernet-loadpost)
 void ViewController::loadPostFromTumblr()
 {
     const QUrl url(m_apiPostUrl);
 
     auto const data = download(url);
     Q_EMIT setStatus(tr("Post downloaded..."));
 
     QDomDocument doc;
     if (!doc.setContent(data)) {
         error(tr("Post format not recognized!"));
     }
 
     auto textOfFirst = [&doc](const char *name) {
         auto const s = QString::fromLatin1(name);
         auto elements = doc.elementsByTagName(s);
         if (elements.isEmpty()) {
             return QString();
         }
         return elements.at(0).toElement().text();
     };
 
     auto const caption = textOfFirst("photo-caption");
     if (caption.isEmpty()) {
         error(tr("Post does not contain a caption!"));
     }
     Q_EMIT setCaption(caption);
     auto const imageUrl = textOfFirst("photo-url");
     if (imageUrl.isEmpty()) {
         error(tr("Post does not contain an image!"));
     }
 
     m_fullPostUrl = attributeTextFor(doc, "post", "url-with-slug");
     if (m_fullPostUrl.isEmpty()) {
         error(tr("Response does not contain URL with slug!"));
     }
     m_imageUrl = QUrl(imageUrl);
     showResourceImage("IMG_20140813_004131-colors-cubed.png");
     Q_EMIT setStatus(tr("Downloading image..."));
     QThread::msleep(500);
 }
 //@@snippet_end
 
 void ViewController::loadImageFromTumblr()
 {
     auto const data = download(m_imageUrl);
     Q_EMIT setStatus(tr("Image downloaded..."));
     const QImage image = QImage::fromData(data);
     if (!image.isNull()) {
         Q_EMIT setImage(image);
         Q_EMIT setStatus(tr("Download complete (see %1).").arg(m_fullPostUrl));
     } else {
         error(tr("Image format error!"));
     }
 }
 
 QByteArray ViewController::download(const QUrl &url)
 {
     QNetworkAccessManager manager;
     QEventLoop loop;
     QObject::connect(&manager, SIGNAL(finished(QNetworkReply *)), &loop, SLOT(quit()));
     auto reply = manager.get(QNetworkRequest(url));
     loop.exec();
     if (reply->error() == QNetworkReply::NoError) {
         const QByteArray data = reply->readAll();
         return data;
     } else {
         error(tr("Unable to download data for \"%1\"!").arg(url.toString()));
         return QByteArray();
     }
 }
 
 //@@snippet_begin(hellointernet-error)
 void ViewController::error(const QString &message)
 {
     showResourceImage("IMG_20140813_004131-colors-cubed.png");
     Q_EMIT setCaption(tr("Error"));
     Q_EMIT setStatus(tr("%1").arg(message));
     throw ThreadWeaver::JobFailed(message);
 }
 //@@snippet_end
 
 void ViewController::showResourceImage(const char *file)
 {
     const QString path(QStringLiteral("://resources/%1").arg(QString::fromLatin1(file)));
     Q_ASSERT(QFile::exists(path));
     const QImage i(path);
     Q_ASSERT(!i.isNull());
     Q_EMIT setImage(i);
 }
 
 QString ViewController::attributeTextFor(const QDomDocument &doc, const char *tag, const char *attribute)
 {
     auto const tagString = QString::fromLatin1(tag);
     auto const attributeString = QString::fromLatin1(attribute);
     auto elements = doc.elementsByTagName(tagString);
     if (elements.isEmpty()) {
         return QString();
     }
     const QString content = elements.at(0).toElement().attribute(attributeString);
     return content;
 }
 
 #include "moc_ViewController.cpp"