WTF did we have two classes for downloading files?

11 files changed, 254 insertions, 384 deletions

diff --git a/src/dialog.cpp b/src/dialog.cpp
index 8399e62..5035b56 100644
--- a/src/dialog.cpp
+++ b/src/dialog.cpp
@@ -9,6 +9,7 @@
 #include <QDesktopWidget>
 #include <QDateTime>
 #include <QTemporaryFile>
+#include <QUrlQuery>
 
 #include "unistd.h"
 #include "stdio.h"
@@ -19,6 +20,7 @@
 #include "globals.h"
 #include "vsession.h"
 #include "choosersettings.h"
+#include "filedownloader.h"
 
 Dialog::Dialog(int defaultTab, bool examMode, QWidget *parent)
     : QDialog(parent), ui(new Ui::Dialog) {
@@ -411,67 +413,211 @@ void Dialog::onCenterTimer() {
     }
 }
 
-void Dialog::addSessionsAfterDownload(QNetworkReply* reply) {
-    QString temp_filename;
+/**
+ * Download lecture list, news and help
+ */
+void Dialog::downloadData(const QString& locationIds) {
+    QUrl listUrl(g_urlBase + "list");
+    QUrlQuery listQuery(listUrl);
 
-    if (reply->error() != QNetworkReply::NoError) {
-        qDebug() << "Error reading from URL: " << reply->error();
+    if (!locationIds.isEmpty()) {
+        listQuery.addQueryItem("locations", locationIds);
+    }
+    if (examMode_) {
+        listQuery.addQueryItem("exams", "exam-mode");
+    }
+    listUrl.setQuery(listQuery);
+    //
+    // Download lecture XML
+    FileDownloader::download(listUrl, [this](QNetworkReply::NetworkError err, const QByteArray& data) {
+        QString temp_filename;
+
+        if (err != QNetworkReply::NoError) {
+            qDebug() << "Error reading from URL: " << err;
+
+            QFile backup_file(TEMP_PATH_XML_LIST);
+
+            if (!backup_file.open(QIODevice::ReadOnly)) {
+                qDebug() << "Cannot read backup file " << TEMP_PATH_XML_LIST << " either";
+                this->removeStatusString(STR_LOADING);
+                this->addStatusString(STR_URL_ERROR);
+                return;
+            }
+            qDebug() << "Using backup file " << TEMP_PATH_XML_LIST;
+            backup_file.close();
+
+            temp_filename = TEMP_PATH_XML_LIST;
+        } else {
+            // write xml to temporary file
+            temp_filename = QDir::tempPath() + "/vmchooser2/vmchooser-XXXXXX.xml";
+            QTemporaryFile tmpfile(temp_filename);
+            if (!tmpfile.open() || tmpfile.write(data) == -1) {
+                return;
+            }
+            tmpfile.close();
+            tmpfile.setAutoRemove(false);
+            temp_filename = tmpfile.fileName();
+        }
+
+        QList<Session*> sessions = VSession::readXmlFile(temp_filename);
+
+        this->removeStatusString(STR_LOADING);
+
+        if (!sessions.isEmpty()) {
+            qSort(sessions.begin(), sessions.end(), myLessThan);
+            this->addItems(sessions, TAB_ALL_VMS);
+            // TODO: Filter user's classes and add to tab[TAB_MY_COURSES]
+            bool showEdit = false;
+            for (QList<Session*>::const_iterator it = sessions.begin(); it != sessions.end(); ++it) {
+                if (reinterpret_cast<VSession*>(*it)->canEdit()) {
+                    showEdit = true;
+                    break;
+                }
+            }
+            if (showEdit) {
+                ui->chkAdminMode->setVisible(true);
+            }
+        } else {
+            this->addStatusString(STR_NO_ITEMS);
+        }
+
+        checkAutostart();
 
-        QFile backup_file(TEMP_PATH_XML_LIST);
+        // select last-session
+        selectPreviousSession();
+        userInteracted_ = true;
+    });
+    //
+    // News
+    FileDownloader::download(QUrl(g_urlBase + "news"), [this](QNetworkReply::NetworkError err, const QByteArray& data) {
+        if (err != QNetworkReply::NoError) {
+            if (g_debugMode) {
+                qDebug() << "Could not get news. Try to get cached news.";
+            }
 
-        if (!backup_file.open(QIODevice::ReadOnly)) {
-            qDebug() << "Cannot read backup file " << TEMP_PATH_XML_LIST << " either";
-            this->removeStatusString(STR_LOADING);
-            this->addStatusString(STR_URL_ERROR);
+            // try to get cached news
+            QFile backup_file(TEMP_PATH_NEWS);
+
+            if (!backup_file.open(QIODevice::ReadOnly)) {
+                if (g_debugMode) {
+                    qDebug() << "Cannot read backup file " << TEMP_PATH_NEWS << " either";
+                }
+                this->ui->newsTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get news."));
+                return;
+            }
+            if (g_debugMode) {
+                qDebug() << "Used backup file " << TEMP_PATH_NEWS;
+            }
+            backup_file.close();
+            return;
+        }
+        QDomDocument doc;
+        if (!doc.setContent(data)) {
+            qDebug() << "News XML contains errors.";
             return;
         }
-        qDebug() << "Using backup file " << TEMP_PATH_XML_LIST;
-        backup_file.close();
+        QDomElement newsNode = doc.firstChildElement("news");
+        QDomElement timeNode = newsNode.firstChildElement("date");
+        QDomElement infoNode = newsNode.firstChildElement("info");
+        QDateTime timestamp;
+        timestamp.setTime_t(timeNode.text().toUInt());
 
-        temp_filename = TEMP_PATH_XML_LIST;
-    } else {
-        QByteArray data = reply->readAll();
+        if (timeNode.isNull() || infoNode.isNull()) {
+            ui->newsTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get news. (//news/date or //news/info missing)"));
+        } else {
+            // format and print news
+            ui->newsTextBrowser->setText(QString("<p style='font-size:16px; margin-bottom: 2px;'>" + newsNode.firstChildElement("headline").text() + "</p> <small>"
+                    + timestamp.toString(Qt::SystemLocaleShortDate) + "</small><p>"
+                    + infoNode.text() + "</p>"));
+        }
 
-        // write xml to temporary file
-        temp_filename = QDir::tempPath() + "/vmchooser2/vmchooser-XXXXXX.xml";
-        QTemporaryFile tmpfile(temp_filename);
-        if (!tmpfile.open() || tmpfile.write(data) == -1) {
+        if (ChooserSettings::getSetting("last-news").toUInt() < timestamp.toTime_t()) {
+            // show news if not seen before
+            on_helpNewsButton_clicked();
+        }
+
+        // update ini
+        ChooserSettings::setSetting("last-news", QString::number(timestamp.toTime_t()));
+
+        // make backup
+        QFile file(TEMP_PATH_NEWS);
+        if (!file.open(QIODevice::WriteOnly)) {
+            if (g_debugMode) {
+                qDebug() << "Could not write XML to " << TEMP_PATH_NEWS;
+            }
             return;
         }
-        tmpfile.close();
-        tmpfile.setAutoRemove(false);
-        temp_filename = tmpfile.fileName();
-    }
 
-    QList<Session*> sessions = VSession::readXmlFile(temp_filename);
+        if (file.write(data) != data.length()) {
+            return;
+        }
+        if (!file.setPermissions(QFile::ReadUser | QFile::ReadGroup | QFile::ReadOther | QFile::WriteUser | QFile::WriteGroup | QFile::WriteOther)) {
+            if (g_debugMode) {
+                qDebug() << "Could not change permissions of file: " << TEMP_PATH_NEWS;
+            }
+        }
+        file.close();
+    });
+    //
+    // Download help
+    FileDownloader::download(QUrl(g_urlBase + "help"), [this](QNetworkReply::NetworkError err, const QByteArray& data) {
+        if (err != QNetworkReply::NoError) {
+            if (g_debugMode) {
+                qDebug() << "Could not get help xml. Try to get cached help...";
+            }
 
-    this->removeStatusString(STR_LOADING);
+            // try to get cached news
+            QFile backup_file(TEMP_PATH_HELP);
 
-    if (!sessions.isEmpty()) {
-        qSort(sessions.begin(), sessions.end(), myLessThan);
-        this->addItems(sessions, TAB_ALL_VMS);
-        // TODO: Filter user's classes and add to tab[TAB_MY_COURSES]
-        bool showEdit = false;
-        for (QList<Session*>::const_iterator it = sessions.begin(); it != sessions.end(); ++it) {
-            if (reinterpret_cast<VSession*>(*it)->canEdit()) {
-                showEdit = true;
-                break;
+            if (!backup_file.open(QIODevice::ReadOnly)) {
+                if (g_debugMode) {
+                    qDebug() << "Cannot read backup file " << TEMP_PATH_HELP << " either";
+                }
+                this->ui->helpTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get help."));
+                return;
+            }
+            if (g_debugMode) {
+                qDebug() << "Used backup file " << TEMP_PATH_HELP;
             }
+            backup_file.close();
+            return;
         }
-        if (showEdit) {
-            ui->chkAdminMode->setVisible(true);
+        QDomDocument doc;
+        if (!doc.setContent(data)) {
+            if (g_debugMode) {
+                qDebug() << "Help file contains errors.";
+            }
+            return;
         }
-    } else {
-        this->addStatusString(STR_NO_ITEMS);
-    }
 
-    checkAutostart();
+        QDomElement newsNode = doc.firstChildElement("news").firstChildElement("info");
+        if (newsNode.isNull()) {
+            ui->helpTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get help (XML has no //news/info)"));
+        } else {
+            ui->helpTextBrowser->setText(newsNode.text());
+        }
 
-    // select last-session
-    selectPreviousSession();
-    userInteracted_ = true;
-}
+        // make backup
+        QFile file(TEMP_PATH_HELP);
+        if (!file.open(QIODevice::WriteOnly)) {
+            if (g_debugMode) {
+                qDebug() << "Could not write XML to " << TEMP_PATH_HELP;
+            }
+            return;
+        }
 
+        if (file.write(data) != data.length()) {
+            return;
+        }
+        if (!file.setPermissions(QFile::ReadUser | QFile::ReadGroup | QFile::ReadOther | QFile::WriteUser | QFile::WriteGroup | QFile::WriteOther)) {
+            if (g_debugMode) {
+                qDebug() << "Could not change permissions of file: " << TEMP_PATH_HELP;
+            }
+        }
+        file.close();
+    });
+    //
+}
 
 void Dialog::mousePressEvent(QMouseEvent * event) {
     QDialog::mousePressEvent(event);
@@ -638,137 +784,6 @@ void Dialog::on_helpNewsButton_clicked() {
     }
 }
 
-void Dialog::addNewsAfterDownload(QNetworkReply* reply) {
-    if (reply->error() != QNetworkReply::NoError) {
-        if (g_debugMode) {
-            qDebug() << "Could not get news. Try to get cached news.";
-        }
-
-        // try to get cached news
-        QFile backup_file(TEMP_PATH_NEWS);
-
-        if (!backup_file.open(QIODevice::ReadOnly)) {
-            if (g_debugMode) {
-                qDebug() << "Cannot read backup file " << TEMP_PATH_NEWS << " either";
-            }
-            this->ui->newsTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get news."));
-            return;
-        }
-        if (g_debugMode) {
-            qDebug() << "Used backup file " << TEMP_PATH_NEWS;
-        }
-        backup_file.close();
-        return;
-    }
-    QByteArray data = reply->readAll();
-    QDomDocument doc;
-    if (!doc.setContent(data)) {
-        qDebug() << "News XML contains errors.";
-        return;
-    }
-    QDomElement newsNode = doc.firstChildElement("news");
-    QDomElement timeNode = newsNode.firstChildElement("date");
-    QDomElement infoNode = newsNode.firstChildElement("info");
-    QDateTime timestamp;
-    timestamp.setTime_t(timeNode.text().toUInt());
-
-    if (timeNode.isNull() || infoNode.isNull()) {
-        ui->newsTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get news. (//news/date or //news/info missing)"));
-    } else {
-        // format and print news
-        ui->newsTextBrowser->setText(QString("<p style='font-size:16px; margin-bottom: 2px;'>" + newsNode.firstChildElement("headline").text() + "</p> <small>"
-                + timestamp.toString(Qt::SystemLocaleShortDate) + "</small><p>"
-                + infoNode.text() + "</p>"));
-    }
-
-    if (ChooserSettings::getSetting("last-news").toUInt() < timestamp.toTime_t()) {
-        // show news if not seen before
-        on_helpNewsButton_clicked();
-    }
-
-    // update ini
-    ChooserSettings::setSetting("last-news", QString::number(timestamp.toTime_t()));
-
-    // make backup
-    QFile file(TEMP_PATH_NEWS);
-    if (!file.open(QIODevice::WriteOnly)) {
-        if (g_debugMode) {
-            qDebug() << "Could not write XML to " << TEMP_PATH_NEWS;
-        }
-        return;
-    }
-
-    if (file.write(data) != data.length()) {
-        return;
-    }
-    if (!file.setPermissions(QFile::ReadUser | QFile::ReadGroup | QFile::ReadOther | QFile::WriteUser | QFile::WriteGroup | QFile::WriteOther)) {
-        if (g_debugMode) {
-            qDebug() << "Could not change permissions of file: " << TEMP_PATH_NEWS;
-        }
-    }
-    file.close();
-}
-
-void Dialog::addHelpAfterDownload(QNetworkReply* reply) {
-    if (reply->error() != QNetworkReply::NoError) {
-        if (g_debugMode) {
-            qDebug() << "Could not get help xml. Try to get cached help...";
-        }
-
-        // try to get cached news
-        QFile backup_file(TEMP_PATH_HELP);
-
-        if (!backup_file.open(QIODevice::ReadOnly)) {
-            if (g_debugMode) {
-                qDebug() << "Cannot read backup file " << TEMP_PATH_HELP << " either";
-            }
-            this->ui->helpTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get help."));
-            return;
-        }
-        if (g_debugMode) {
-            qDebug() << "Used backup file " << TEMP_PATH_HELP;
-        }
-        backup_file.close();
-        return;
-    }
-
-    QByteArray data = reply->readAll();
-    QDomDocument doc;
-
-    if (!doc.setContent(data)) {
-        if (g_debugMode) {
-            qDebug() << "Help file contains errors.";
-        }
-        return;
-    }
-
-    QDomElement newsNode = doc.firstChildElement("news").firstChildElement("info");
-    if (newsNode.isNull()) {
-        ui->helpTextBrowser->setText(QCoreApplication::instance()->translate("Dialog", "Could not get help (XML has no //news/info)"));
-    } else {
-        ui->helpTextBrowser->setText(newsNode.text());
-    }
-
-    // make backup
-    QFile file(TEMP_PATH_HELP);
-    if (!file.open(QIODevice::WriteOnly)) {
-        if (g_debugMode) {
-            qDebug() << "Could not write XML to " << TEMP_PATH_HELP;
-        }
-        return;
-    }
-
-    if (file.write(data) != data.length()) {
-        return;
-    }
-    if (!file.setPermissions(QFile::ReadUser | QFile::ReadGroup | QFile::ReadOther | QFile::WriteUser | QFile::WriteGroup | QFile::WriteOther)) {
-        if (g_debugMode) {
-            qDebug() << "Could not change permissions of file: " << TEMP_PATH_HELP;
-        }
-    }
-    file.close();
-}
-
 void Dialog::keyPressEvent(QKeyEvent* event) {
     switch(event->key()) {
     case Qt::Key_Return:    this->on_pushButtonStart_clicked(); break;
diff --git a/src/dialog.h b/src/dialog.h
index ccdccd2..b38aeac 100644
--- a/src/dialog.h
+++ b/src/dialog.h
@@ -29,6 +29,7 @@ class Dialog : public QDialog {
     static const int TAB_MY_COURSES = 1;
     static const int TAB_ALL_VMS = 2;
     static const int TAB_COUNT = 3;
+
   public: // Public methods
     explicit Dialog(int defaultTab = -1, bool examMode = false, QWidget *parent = nullptr);
     ~Dialog();
@@ -40,10 +41,13 @@ class Dialog : public QDialog {
     void selectPreviousSession();
     void setTheme();
     void startSession(const QString& name);
+    void downloadData(const QString& locationIds);
 
   protected: // Overrides
     void changeEvent(QEvent *e);
     void mousePressEvent(QMouseEvent *event);
+    bool eventFilter(QObject *target, QEvent *event);
+    void keyPressEvent(QKeyEvent * e);
 
   private: // Private vars n methods
     Ui::Dialog *ui;
@@ -62,7 +66,6 @@ class Dialog : public QDialog {
     void onTabButtonChanged(int tab);
     void configClearButton();
     void setListModel(SessionTreeModel *model);
-    void keyPressEvent(QKeyEvent * e);
     void selectFirstElement();
 
     void checkAutostart();
@@ -85,12 +88,6 @@ class Dialog : public QDialog {
     void on_leftKey();
     void on_rightKey();
     void on_spaceKey();
-
-  public slots:
-    void addSessionsAfterDownload(QNetworkReply* reply);
-    void addNewsAfterDownload(QNetworkReply* reply);
-    void addHelpAfterDownload(QNetworkReply* reply);
-    bool eventFilter(QObject *target, QEvent *event);
 };
 
 #endif // DIALOG_H
diff --git a/src/filedownloader.cpp b/src/filedownloader.cpp
index e0b0289..30f30da 100644
--- a/src/filedownloader.cpp
+++ b/src/filedownloader.cpp
@@ -1,72 +1,46 @@
-/*
- * filedownloader.cpp
- *
- *  Created on: Mar 7, 2014
- *      Author: nils
- */
-
-#include <QFileInfo>
-
 #include "filedownloader.h"
 
+#include <QNetworkAccessManager>
+#include <QNetworkRequest>
+
 // Maximum size of download
-#define MAXSIZE (200000)
+#define MAXSIZE (400000)
 
 static QNetworkAccessManager m_WebCtrl;
 
-FileDownloader::FileDownloader(const QUrl& fileUrl, QObject *parent) :
-    QObject(parent), started(false), url(fileUrl) {
-}
-
-FileDownloader::~FileDownloader() {
+static void killReply(QNetworkReply *reply);
 
-}
-
-bool FileDownloader::downloadFile() {
-    if (this->started)
-        return true;
-    QNetworkRequest request(this->url);
+bool FileDownloader::download(const QUrl& fileUrl, const std::function <void (QNetworkReply::NetworkError, const QByteArray&)>& f) {
+    QNetworkRequest request(fileUrl);
     request.setAttribute(QNetworkRequest::FollowRedirectsAttribute, true);
     QNetworkReply *reply = m_WebCtrl.get(request);
     if (reply == nullptr)
         return false;
-    this->started = true;
-    connect(reply, SIGNAL(finished()), SLOT(fileDownloaded()));
-    connect(reply, SIGNAL(downloadProgress(qint64, qint64)), SLOT(downloadProgress(qint64, qint64)));
-    return true;
-}
-
-/*
- * Slots from networkreply
- */
-
-void FileDownloader::downloadFailed(QNetworkReply::NetworkError) {
-    QNetworkReply *reply = reinterpret_cast<QNetworkReply*>(this->sender());
-    killReply(reply);
-    emit downloaded(this->url, QByteArray());
-}
-
-void FileDownloader::fileDownloaded() {
-    QNetworkReply *reply = reinterpret_cast<QNetworkReply*>(this->sender());
-    if (reply == nullptr)
-        return;
-    QByteArray downloadedData(reply->readAll());
-    killReply(reply);
-    //emit a signal
-    emit downloaded(this->url, downloadedData);
-}
-
-void FileDownloader::downloadProgress(qint64 received, qint64 totalSize) {
-    QNetworkReply *reply = reinterpret_cast<QNetworkReply*>(this->sender());
-    if (reply == nullptr)
-        return;
-    if (received > MAXSIZE || totalSize > MAXSIZE) {
+    // Handle normal finish
+    QObject::connect(reply, &QNetworkReply::finished, [reply, f, fileUrl]() {
+        QByteArray downloadedData(reply->readAll());
         killReply(reply);
-        emit downloaded(this->url, QByteArray());
-    }
+        f(QNetworkReply::NoError, downloadedData);
+    });
+    // Handle files that are too large
+    QObject::connect(reply, &QNetworkReply::downloadProgress, [reply, f, fileUrl](qint64 received, qint64 totalSize) {
+        if (received > MAXSIZE || totalSize > MAXSIZE) {
+            qDebug() << fileUrl << "too large";
+            killReply(reply);
+            f(QNetworkReply::NetworkError::UnknownNetworkError, QByteArray());
+        }
+    });
+    // Handle errors
+    QObject::connect(reply, static_cast<void (QNetworkReply::*)(QNetworkReply::NetworkError)>(&QNetworkReply::error),
+            [reply, f, fileUrl](QNetworkReply::NetworkError err) {
+        qDebug() << fileUrl << "error" << err;
+        killReply(reply);
+        f(err, QByteArray());
+    });
+    return true;
 }
 
-void FileDownloader::killReply(QNetworkReply *reply) {
+static void killReply(QNetworkReply *reply) {
     if (reply == nullptr)
         return;
     reply->blockSignals(true);
diff --git a/src/filedownloader.h b/src/filedownloader.h
index ec49c23..b20c6a8 100644
--- a/src/filedownloader.h
+++ b/src/filedownloader.h
@@ -1,51 +1,15 @@
-/*
- * filedownloader.h
- *
- *  Created on: Mar 7, 2014
- *      Author: nils
- */
-
 #ifndef FILEDOWNLOADER_H_
 #define FILEDOWNLOADER_H_
 
 #include <QObject>
 #include <QByteArray>
-#include <QNetworkAccessManager>
-#include <QNetworkRequest>
 #include <QNetworkReply>
 
-class FileDownloader : public QObject
+class FileDownloader
 {
-    Q_OBJECT
-
 public:
 
-    explicit FileDownloader(const QUrl& fileUrl, QObject *parent = nullptr);
-
-    virtual ~FileDownloader();
-
-    bool downloadFile();
-
-signals:
-
-    /**
-     * Triggered when the download has finished.
-     * On error, downloadedData will be empty.
-     */
-    void downloaded(const QUrl& url, const QByteArray& downloadedData);
-
-private slots:
-
-    void fileDownloaded();
-    void downloadFailed(QNetworkReply::NetworkError code);
-    void downloadProgress(qint64 received, qint64 totalSize);
-
-private:
-
-    void killReply(QNetworkReply *reply);
-
-    bool started;
-    QUrl url;
+    static bool download(const QUrl& fileUrl, const std::function <void (QNetworkReply::NetworkError, const QByteArray&)>& f);
 
 };
 
diff --git a/src/httpxmldownloader.cpp b/src/httpxmldownloader.cpp
deleted file mode 100644
index c143995..0000000
--- a/src/httpxmldownloader.cpp
+++ /dev/null
@@ -1,22 +0,0 @@
-
-#include "httpxmldownloader.h"
-#include <QDebug>
-#include <QUrlQuery>
-
-HttpXmlDownloader::HttpXmlDownloader() {
-    nam = new QNetworkAccessManager(this);
-}
-
-QNetworkReply* HttpXmlDownloader::makeRequest(const QString& xmlurl, const QString& locationIds) {
-    QUrl url(xmlurl);
-    if (!locationIds.isEmpty()) {
-        QUrlQuery query(url);
-        query.addQueryItem("locations", locationIds);
-        url.setQuery(query);
-    }
-    return nam->get(QNetworkRequest(url));
-}
-
-void HttpXmlDownloader::connectSlot(QObject* obj, const char* slot) {
-    QObject::connect(nam, SIGNAL(finished(QNetworkReply*)), obj, slot);
-}
diff --git a/src/httpxmldownloader.h b/src/httpxmldownloader.h
deleted file mode 100644
index dbca643..0000000
--- a/src/httpxmldownloader.h
+++ /dev/null
@@ -1,19 +0,0 @@
-
-#ifndef HTTPTEST_H_
-#define HTTPTEST_H_
-
-#include <QNetworkAccessManager>
-#include <QUrl>
-#include <QNetworkRequest>
-#include <QNetworkReply>
-
-class HttpXmlDownloader : public QObject {
-    Q_OBJECT
-    QNetworkAccessManager* nam;
-public:
-    HttpXmlDownloader();
-    QNetworkReply* makeRequest(const QString& xmlurl, const QString& locationIds = QString());
-    void connectSlot(QObject* obj, const char* slot);
-};
-
-#endif /* HTTPTEST_H_ */
diff --git a/src/main.cpp b/src/main.cpp
index 46d8bc5..044f477 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -16,9 +16,7 @@
 #include "command_line_options.h"
 #include "dialog.h"
 #include "globals.h"
-#include "vsession.h"
 #include "xsession.h"
-#include "httpxmldownloader.h"
 #include "choosersettings.h"
 
 int main(int argc, char *argv[]) {
@@ -288,27 +286,7 @@ int main(int argc, char *argv[]) {
 
     Dialog w(defaultTab, cmdOptions.contains("exam-mode"));
 
-    /* DOWNLOAD VSESSIONS */
-    HttpXmlDownloader httpxmldownloader;
-    httpxmldownloader.connectSlot(&w,
-            SLOT(addSessionsAfterDownload(QNetworkReply*)));
-
-    // read xml and add items later
-    if (cmdOptions.contains("exam-mode")) {
-        httpxmldownloader.makeRequest(g_urlBase + "list?exams=exam-mode", locationIds);
-    } else {
-        httpxmldownloader.makeRequest(g_urlBase + "list", locationIds);
-    }
-
-    /* DOWNLOAD NEWS */
-    HttpXmlDownloader news_downloader;
-    news_downloader.connectSlot(&w, SLOT(addNewsAfterDownload(QNetworkReply*)));
-    news_downloader.makeRequest(g_urlBase + "news");
-
-    /* DOWNLOAD HELP-SECTION */
-    HttpXmlDownloader help_downloader;
-    help_downloader.connectSlot(&w, SLOT(addHelpAfterDownload(QNetworkReply*)));
-    help_downloader.makeRequest(g_urlBase + "help");
+    w.downloadData(locationIds);
 
     w.setTheme();
 
diff --git a/src/sessionsiconholder.cpp b/src/sessionsiconholder.cpp
index 5180658..8eecf26 100644
--- a/src/sessionsiconholder.cpp
+++ b/src/sessionsiconholder.cpp
@@ -1,10 +1,3 @@
-/*
- * sessionsiconholder.cpp
- *
- *  Created on: Mar 7, 2014
- *      Author: nils
- */
-
 #include <QHash>
 #include <QtDebug>
 #include <QFile>
@@ -29,34 +22,6 @@ SessionsIconHolder::SessionsIconHolder() {
     QDir().mkpath(TEMP_PATH_ICONS);
 }
 
-void SessionsIconHolder::afterDownload(const QUrl& url, const QByteArray& downloadedData) {
-    // save the data to disk
-    QString strUrl(url.toString());
-    QString file_path(url2filename(strUrl));
-    QFile file(file_path);
-    if (!file.open(QFile::WriteOnly)) {
-        if (g_debugMode) {
-            qDebug() << "Could not write file: " << file_path;
-        }
-        return;
-    }
-    file.write(downloadedData);
-
-    if (file.write(downloadedData) != downloadedData.length()) {
-        if (g_debugMode) {
-            qDebug() << "Could not write file: " << file_path;
-        }
-        return;
-    }
-
-    file.close();
-
-    QIcon icon(file_path);
-    icons.insert(strUrl, icon);
-
-    emit iconDownloaded(url, icon);
-}
-
 QIcon SessionsIconHolder::getIcon(const QString& name) {
     // check if icon was loaded before
     if (icons.contains(name)) {
@@ -100,10 +65,33 @@ QIcon SessionsIconHolder::getIcon(const QUrl& url) {
     icons.insert(strUrl, QIcon());
 
     // else load icon from url
-    FileDownloader* fileDownloader = new FileDownloader(url, this);
-    QObject::connect(fileDownloader, SIGNAL(downloaded(const QUrl&, const QByteArray&)),
-            this, SLOT(afterDownload(const QUrl&, const QByteArray&)));
-    fileDownloader->downloadFile();
+    FileDownloader::download(url, [this, url](QNetworkReply::NetworkError, const QByteArray &downloadedData) {
+        // save the data to disk
+        QString strUrl(url.toString());
+        QString file_path(url2filename(strUrl));
+        QFile file(file_path);
+        if (!file.open(QFile::WriteOnly)) {
+            if (g_debugMode) {
+                qDebug() << "Could not write file: " << file_path;
+            }
+            return;
+        }
+        file.write(downloadedData);
+
+        if (file.write(downloadedData) != downloadedData.length()) {
+            if (g_debugMode) {
+                qDebug() << "Could not write file: " << file_path;
+            }
+            return;
+        }
+
+        file.close();
+
+        QIcon icon(file_path);
+        icons.insert(strUrl, icon);
+
+        emit iconDownloaded(url, icon);
+    });
 
     return QIcon();
 }
diff --git a/src/sessionsiconholder.h b/src/sessionsiconholder.h
index 06ca73c..048236a 100644
--- a/src/sessionsiconholder.h
+++ b/src/sessionsiconholder.h
@@ -17,7 +17,6 @@
 
 #include "globals.h"
 #include "sessionsiconholder.h"
-#include "filedownloader.h"
 
 class SessionTreeModel;
 
@@ -36,9 +35,6 @@ public:
     QIcon getIcon(const QString& name);
     QIcon getIcon(const QUrl& url);
     static SessionsIconHolder* get() { if (instance == nullptr) instance = new SessionsIconHolder(); return instance; }
-
-public slots:
-    void afterDownload(const QUrl& url, const QByteArray& downloadedData);
 };
 
 #endif /* SESSIONSICONHOLDER_H_ */
diff --git a/src/vsession.h b/src/vsession.h
index 08885cc..18d5c38 100644
--- a/src/vsession.h
+++ b/src/vsession.h
@@ -6,7 +6,6 @@
 #include <QDomDocument>
 #include <QDir>
 #include "session.h"
-#include "httpxmldownloader.h"
 #include "globals.h"
 
 enum ImgType {
@@ -88,9 +87,7 @@ class VSession : public Session {
 
     bool operator<(const Session& other) const;
 
-    static QList<Session*> readXmlDir(const QString& path);
     static QList<Session*> readXmlFile(const QString& filepath);
-    static void addSessionsAfterDownload(QNetworkReply* reply);
 
   private:
     QList<QString> keywords_;
diff --git a/src/xsession.cpp b/src/xsession.cpp
index d72aecf..2d7214a 100644
--- a/src/xsession.cpp
+++ b/src/xsession.cpp
@@ -23,9 +23,11 @@ void XSession::init(const QString& name, const QString& exec,
     this->exec_ = exec;
     this->comment_ = comment;
     this->icon_ = icon;
+    this->priority_ = 0;
 }
 
 bool XSession::init(const QString& filename) {
+    this->priority_ = 0;
     QSettings settings(filename, QSettings::IniFormat);
     settings.setIniCodec("UTF-8");