first implementation of image only download

core/networkaccess.h

@@ -0,0 +1,82 @@
+/*
+ * Squawk messenger. 
+ * Copyright (C) 2019 Yury Gubich <blue@macaw.me>
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef CORE_NETWORKACCESS_H
+#define CORE_NETWORKACCESS_H
+
+#include <QObject>
+#include <QNetworkAccessManager>
+#include <QNetworkReply>
+#include <QNetworkRequest>
+#include <QFileInfo>
+#include <QFile>
+#include <QStandardPaths>
+
+#include <set>
+
+#include "storage.h"
+
+namespace Core {
+
+/**
+ * @todo write docs
+ */
+class NetworkAccess : public QObject
+{
+    Q_OBJECT
+    struct Download;
+public:
+    NetworkAccess(QObject* parent = nullptr);
+    virtual ~NetworkAccess();
+    
+    void start();
+    void stop();
+    
+signals:
+    void fileLocalPathResponse(const QString& messageId, const QString& path);
+    void downloadFileProgress(const QString& messageId, qreal value);
+    
+public slots:
+    void fileLocalPathRequest(const QString& messageId, const QString& url);
+    void downladFileRequest(const QString& messageId, const QString& url);
+    
+private:
+    void startDownload(const QString& messageId, const QString& url);
+    
+private slots:
+    void onDownloadProgress(qint64 bytesReceived, qint64 bytesTotal);
+    void onRequestError(QNetworkReply::NetworkError code);
+    void onRequestFinished();
+    
+private:
+    bool running;
+    QNetworkAccessManager manager;
+    Storage files;
+    std::map<QString, Download*> downloads;
+    
+    struct Download {
+        std::set<QString> messages;
+        qreal progress;
+        QNetworkReply* reply;
+        bool success;
+    };
+};
+
+}
+
+#endif // CORE_NETWORKACCESS_H