a bit of refactor, fix the time to request next portion of messages in ui, fancy shadows are back!

ui/utils/shadowoverlay.h

@@ -0,0 +1,58 @@
+/*
+ * 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 SHADOWOVERLAY_H
+#define SHADOWOVERLAY_H
+
+#include <QWidget>
+#include <QImage>
+#include <QPainter>
+#include <QColor>
+#include <QPaintEvent>
+#include <QResizeEvent>
+
+#include <ui/utils/eb.h>
+
+/**
+ * @todo write docs
+ */
+class ShadowOverlay : public QWidget {
+    
+public:
+    ShadowOverlay(unsigned int radius = 10, unsigned int thickness = 1, const QColor& color = Qt::black, QWidget* parent = nullptr);
+    
+    void setFrames(bool top, bool right, bool bottom, bool left);
+    
+protected:
+    void updateImage();
+    
+    void paintEvent(QPaintEvent * event) override;
+    void resizeEvent(QResizeEvent * event) override;
+    
+private:
+    bool top;
+    bool right;
+    bool bottom;
+    bool left;
+    unsigned int thickness;
+    unsigned int radius;
+    QColor color;
+    QImage shadow;
+};
+
+#endif // SHADOWOVERLAY_H