Advanced implementation of auto-fetch-guess feature.

src/core/databasefactory.h

@@ -5,17 +5,6 @@
 #include <QPointer>
 #include <QSqlDatabase>
 
-// TODO: přidat podporu pro mysql
-// nemužu mit stejny SQL kod pro mysql a sqlite
-// ale musim docilit aby oba kody SQL delaly tabulky
-// se stejnymi atributy - stejnymi nazvy sloupcu
-// PROBLEMY se mysql: nutno pridat AUTO_INCREMENT u int primary keyů
-// taky bacha na nazvy sloupců, třeba
-// key a read sou klicovy slouva a fejlne to tak
-// taky bacha ze typ TEXT nemuze bejt dost dobre
-// pouzitej v UNIQUE CHECK, misto toho se da pouzit treba
-// VARCHAR (100)
-
 
 class DatabaseFactory : public QObject {
     Q_OBJECT

src/core/feedsmodelstandardfeed.cpp

@@ -13,6 +13,11 @@
 #include <QTextCodec>
 #include <QSqlQuery>
 
+#include <QDomDocument>
+#include <QDomNode>
+#include <QDomElement>
+#include <QXmlStreamReader>
+
 
 FeedsModelStandardFeed::FeedsModelStandardFeed(FeedsModelRootItem *parent_item)
   : FeedsModelFeed(parent_item),
@@ -44,15 +49,117 @@ FeedsModelStandardFeed *FeedsModelStandardFeed::loadFromRecord(const QSqlRecord
   return feed;
 }
 
-FeedsModelStandardFeed *FeedsModelStandardFeed::guessFeed(const QString &url,
-                                                          const QString &username,
-                                                          const QString &password) {
-  // TODO: http://www.google.com/s2/favicons?domain=root.cz
-  // ZISKAT ikonu (napsat taky aby se dala ikona pro
-  // dane url ziskavat taky samostatne
-  // pak ziskat informace o kanalu
+QPair<FeedsModelStandardFeed*, QNetworkReply::NetworkError> FeedsModelStandardFeed::guessFeed(const QString &url,
+                                                                                              const QString &username,
+                                                                                              const QString &password) {
+  QPair<FeedsModelStandardFeed*, QNetworkReply::NetworkError> result; result.first = NULL;
 
-  return NULL;
+  // Try to obtain icon.
+  QIcon icon_data;
+
+  if (NetworkFactory::downloadIcon(url,
+                                   5000,
+                                   icon_data) == QNetworkReply::NoError) {
+    // Icon for feed was downloaded and is stored now in _icon_data.
+    result.first = new FeedsModelStandardFeed();
+    result.first->setIcon(icon_data);
+  }
+
+  QByteArray feed_contents;
+  if ((result.second = NetworkFactory::downloadFeedFile(url,
+                                                        Settings::instance()->value(APP_CFG_FEEDS, "feed_update_timeout", DOWNLOAD_TIMEOUT).toInt(),
+                                                        feed_contents,
+                                                        true,
+                                                        username,
+                                                        password)) == QNetworkReply::NoError) {
+    // Feed XML was obtained, now we need to try to guess
+    // its encoding before we can read further data.
+
+    QXmlStreamReader xml_stream_reader(feed_contents);
+    QString xml_schema_encoding;
+    QString xml_contents_encoded;
+
+    // We have several chances to read the XML version directly
+    // from XML declaration.
+    for (int i = 0; i < 2 && !xml_stream_reader.atEnd(); i++) {
+      if ((xml_schema_encoding = xml_stream_reader.documentEncoding().toString()).isEmpty()) {
+        xml_stream_reader.readNext();
+      }
+      else {
+        break;
+      }
+    }
+
+    QTextCodec *custom_codec = QTextCodec::codecForName(xml_schema_encoding.toLocal8Bit());
+
+    if (custom_codec != NULL) {
+      // Feed encoding was probably guessed.
+      xml_contents_encoded = custom_codec->toUnicode(feed_contents);
+      result.first->setEncoding(xml_schema_encoding);
+    }
+    else {
+      // Feed encoding probably not guessed, set it as
+      // default.
+      xml_contents_encoded = feed_contents;
+      result.first->setEncoding(DEFAULT_FEED_ENCODING);
+    }
+
+    // Feed XML was obtained, guess it now.
+    QDomDocument xml_document;
+
+    if (!xml_document.setContent(xml_contents_encoded)) {
+      // XML is invalid, exit.
+      return result;
+    }
+
+    QDomElement root_element = xml_document.documentElement();
+    QString root_tag_name = root_element.tagName();
+
+    if (root_tag_name == "rdf:RDF") {
+      if (result.first == NULL) {
+        result.first = new FeedsModelStandardFeed();
+      }
+
+      // We found RDF feed.
+      QDomElement channel_element = root_element.namedItem("channel").toElement();
+
+      result.first->setType(StandardRdf);
+      result.first->setTitle(channel_element.namedItem("title").toElement().text());
+      result.first->setDescription(channel_element.namedItem("description").toElement().text());
+    }
+    else if (root_tag_name == "rss") {
+      if (result.first == NULL) {
+        result.first = new FeedsModelStandardFeed();
+      }
+
+      // We found RSS 0.91/0.92/0.93/2.0/2.0.1 feed.
+      QString rss_type = root_element.attribute("version", "2.0");
+
+      if (rss_type == "0.91" || rss_type == "0.92" || rss_type == "0.93") {
+        result.first->setType(StandardRss0X);
+      }
+      else {
+        result.first->setType(StandardRss2X);
+      }
+
+      QDomElement channel_element = root_element.namedItem("channel").toElement();
+
+      result.first->setTitle(channel_element.namedItem("title").toElement().text());
+      result.first->setDescription(channel_element.namedItem("description").toElement().text());
+    }
+    else if (root_tag_name == "feed") {
+      if (result.first == NULL) {
+        result.first = new FeedsModelStandardFeed();
+      }
+
+      // We found ATOM feed.
+      result.first->setType(StandardAtom10);
+      result.first->setTitle(root_element.namedItem("title").toElement().text());
+      result.first->setDescription(root_element.namedItem("subtitle").toElement().text());
+    }
+  }
+
+  return result;
 }
 
 QVariant FeedsModelStandardFeed::data(int column, int role) const {

src/core/feedsmodelstandardfeed.h

@@ -5,6 +5,8 @@
 
 #include <QDateTime>
 #include <QSqlRecord>
+#include <QPair>
+#include <QNetworkReply>
 
 
 class Message;
@@ -83,10 +85,12 @@ class FeedsModelStandardFeed : public FeedsModelFeed {
 
     // Tries to guess feed hidden under given URL
     // and uses given credentials.
-    // Returns NULL if something failed.
-    static FeedsModelStandardFeed *guessFeed(const QString &url,
-                                             const QString &username,
-                                             const QString &password);
+    // Returns pointer to guessed feed (if at least partially
+    // guessed) and retrieved error/status code from network layer
+    // or NULL feed.
+    static QPair<FeedsModelStandardFeed*, QNetworkReply::NetworkError> guessFeed(const QString &url,
+                                                                                 const QString &username,
+                                                                                 const QString &password);
 
   protected:
     // Persistently stores given messages into the database

src/core/networkfactory.cpp

@@ -5,11 +5,31 @@
 
 #include <QEventLoop>
 #include <QTimer>
+#include <QTextDocument>
 
 
 NetworkFactory::NetworkFactory() {
 }
 
+QNetworkReply::NetworkError NetworkFactory::downloadIcon(const QString &url,
+                                                         int timeout,
+                                                         QIcon &output) {
+  QString google_s2_with_url = QString("http://www.google.com/s2/favicons?domain=%1").arg(Qt::escape(url));
+  QByteArray icon_data;
+
+  QNetworkReply::NetworkError network_result =  downloadFeedFile(google_s2_with_url,
+                                                                 timeout,
+                                                                 icon_data);
+
+  if (network_result == QNetworkReply::NoError) {
+    QPixmap icon_pixmap;
+    icon_pixmap.loadFromData(icon_data);
+    output = QIcon(icon_pixmap);
+  }
+
+  return network_result;
+}
+
 QNetworkReply::NetworkError NetworkFactory::downloadFeedFile(const QString &url,
                                                              int timeout,
                                                              QByteArray &output,

src/core/networkfactory.h

@@ -12,6 +12,12 @@ class NetworkFactory {
     explicit NetworkFactory();
 
   public:
+    // Performs SYNCHRONOUS download if favicon for the site,
+    // given URL belongs to.
+    static QNetworkReply::NetworkError downloadIcon(const QString &url,
+                                                    int timeout,
+                                                    QIcon &output);
+
     // Performs SYNCHRONOUS download of file with given URL
     // and given timeout.
     static QNetworkReply::NetworkError downloadFeedFile(const QString &url,

src/gui/formstandardfeeddetails.cpp

@@ -16,6 +16,8 @@
 #include <QTextCodec>
 #include <QFileDialog>
 #include <QMenu>
+#include <QPair>
+#include <QNetworkReply>
 
 
 FormStandardFeedDetails::FormStandardFeedDetails(FeedsModel *model, QWidget *parent)
@@ -240,6 +242,25 @@ void FormStandardFeedDetails::apply() {
   }
 }
 
+void FormStandardFeedDetails::guessFeed() {
+  QPair<FeedsModelStandardFeed*, QNetworkReply::NetworkError> result =  FeedsModelStandardFeed::guessFeed(m_ui->m_txtUrl->lineEdit()->text(),
+                                                                                                          m_ui->m_txtUsername->lineEdit()->text(),
+                                                                                                          m_ui->m_txtPassword->lineEdit()->text());
+
+  if (result.first != NULL) {
+    // Icon was perhaps guessed.
+    m_ui->m_btnIcon->setIcon(result.first->icon());
+
+    m_ui->m_txtTitle->lineEdit()->setText(result.first->title());
+    m_ui->m_txtDescription->lineEdit()->setText(result.first->description());
+    m_ui->m_cmbType->setCurrentIndex(m_ui->m_cmbType->findData(QVariant::fromValue((int) result.first->type())));
+    m_ui->m_cmbEncoding->setCurrentIndex(m_ui->m_cmbEncoding->findData(result.first->encoding(), Qt::DisplayRole));
+  }
+  else {
+    // No feed guessed, even no icon available.
+  }
+}
+
 void FormStandardFeedDetails::createConnections() {
   // General connections.
   connect(m_ui->m_buttonBox, SIGNAL(accepted()),
@@ -258,6 +279,8 @@ void FormStandardFeedDetails::createConnections() {
           this, SLOT(onAuthenticationSwitched()));
   connect(m_ui->m_cmbAutoUpdateType, SIGNAL(currentIndexChanged(int)),
           this, SLOT(onAutoUpdateTypeChanged(int)));
+  connect(m_btnLoadDataFromInternet, SIGNAL(clicked()),
+          this, SLOT(guessFeed()));
 
   // Icon connections.
   connect(m_actionLoadIconFromFile, SIGNAL(triggered()), this, SLOT(onLoadIconFromFile()));

src/gui/formstandardfeeddetails.h

@@ -30,6 +30,7 @@ class FormStandardFeedDetails : public QDialog {
   protected slots:
     // Applies changes.
     void apply();
+    void guessFeed();
 
     // Trigerred when title/description/url/username/password changes.
     void onTitleChanged(const QString &new_title);