coding style fixes

git-svn-id: http://svn.code.sf.net/p/qmmp-dev/code/trunk/qmmp@9472 90c681e8-e032-0410-971d-27865f9a5e38

66 files changed, 329 insertions, 461 deletions

diff --git a/src/plugins/Input/archive/archivetagreader.cpp b/src/plugins/Input/archive/archivetagreader.cpp
index 2ec7fe524..8e9118ba8 100644
--- a/src/plugins/Input/archive/archivetagreader.cpp
+++ b/src/plugins/Input/archive/archivetagreader.cpp
@@ -99,12 +99,12 @@ public:
     {}
 
 private:
+    QIODevice *m_input;
 #ifdef Q_OS_WIN
     QString m_fileName;
 #else
     QByteArray m_fileName;
 #endif
-    QIODevice *m_input;
 };
 
 ArchiveTagReader::ArchiveTagReader(QIODevice *input, const QString &url)
diff --git a/src/plugins/Transports/http/httpinputsource.cpp b/src/plugins/Transports/http/httpinputsource.cpp
index 8f8940997..14870cbdf 100644
--- a/src/plugins/Transports/http/httpinputsource.cpp
+++ b/src/plugins/Transports/http/httpinputsource.cpp
@@ -28,7 +28,7 @@ HTTPInputSource::HTTPInputSource(const QString &url, QObject *parent) : InputSou
     connect(m_reader, SIGNAL(error()),SIGNAL(error()));
 }
 
-QIODevice *HTTPInputSource::ioDevice()
+QIODevice *HTTPInputSource::ioDevice() const
 {
     return m_reader;
 }
@@ -39,12 +39,12 @@ bool HTTPInputSource::initialize()
     return true;
 }
 
-bool HTTPInputSource::isReady()
+bool HTTPInputSource::isReady() const
 {
     return m_reader->isOpen();
 }
 
-bool HTTPInputSource::isWaiting()
+bool HTTPInputSource::isWaiting() const
 {
     return (!m_reader->bytesAvailable() && m_reader->isOpen());
 }
diff --git a/src/plugins/Transports/http/httpinputsource.h b/src/plugins/Transports/http/httpinputsource.h
index 515e7306b..0d5fa12ad 100644
--- a/src/plugins/Transports/http/httpinputsource.h
+++ b/src/plugins/Transports/http/httpinputsource.h
@@ -34,10 +34,10 @@ Q_OBJECT
 public:
     explicit HTTPInputSource(const QString &path, QObject *parent = nullptr);
 
-    QIODevice *ioDevice() override;
+    QIODevice *ioDevice() const override;
     bool initialize() override;
-    bool isReady() override;
-    bool isWaiting() override;
+    bool isReady() const override;
+    bool isWaiting() const override;
     QString contentType() const override;
 
 private:
diff --git a/src/plugins/Transports/mms/mmsinputsource.cpp b/src/plugins/Transports/mms/mmsinputsource.cpp
index dbc1075c3..2a021f405 100644
--- a/src/plugins/Transports/mms/mmsinputsource.cpp
+++ b/src/plugins/Transports/mms/mmsinputsource.cpp
@@ -28,7 +28,7 @@ MMSInputSource::MMSInputSource(const QString &url, QObject *parent) : InputSourc
     connect(m_reader, SIGNAL(error()),SIGNAL(error()));
 }
 
-QIODevice *MMSInputSource::ioDevice()
+QIODevice *MMSInputSource::ioDevice() const
 {
     return m_reader;
 }
@@ -39,12 +39,12 @@ bool MMSInputSource::initialize()
     return true;
 }
 
-bool MMSInputSource::isReady()
+bool MMSInputSource::isReady() const
 {
     return m_reader->isOpen();
 }
 
-bool MMSInputSource::isWaiting()
+bool MMSInputSource::isWaiting() const
 {
     return (!m_reader->bytesAvailable() && m_reader->isOpen());
 }
diff --git a/src/plugins/Transports/mms/mmsinputsource.h b/src/plugins/Transports/mms/mmsinputsource.h
index afe8aaa61..df0bd637d 100644
--- a/src/plugins/Transports/mms/mmsinputsource.h
+++ b/src/plugins/Transports/mms/mmsinputsource.h
@@ -34,10 +34,10 @@ Q_OBJECT
 public:
     explicit MMSInputSource(const QString &path, QObject *parent = nullptr);
 
-    QIODevice *ioDevice() override;
+    QIODevice *ioDevice() const override;
     bool initialize() override;
-    bool isReady() override;
-    bool isWaiting() override;
+    bool isReady() const override;
+    bool isWaiting() const override;
     QString contentType() const override;
 
 private:
diff --git a/src/plugins/Ui/skinned/skin.cpp b/src/plugins/Ui/skinned/skin.cpp
index 979484495..33d3e1018 100644
--- a/src/plugins/Ui/skinned/skin.cpp
+++ b/src/plugins/Ui/skinned/skin.cpp
@@ -918,7 +918,7 @@ QRegion Skin::createRegion(const QString &path, const QString &group)
         for (int j = 0; j < numPoints.at(i).toInt() * 2 && n != numbers.constEnd(); j++)
         {
             lp << n->toInt();
-            n ++;
+            ++n;
         }
         QVector<QPoint> points;
 
diff --git a/src/plugins/Ui/skinned/skinnedsettings.cpp b/src/plugins/Ui/skinned/skinnedsettings.cpp
index 12fb7c52d..1da0b8718 100644
--- a/src/plugins/Ui/skinned/skinnedsettings.cpp
+++ b/src/plugins/Ui/skinned/skinnedsettings.cpp
@@ -201,7 +201,7 @@ void SkinnedSettings::loadSkins()
 #endif
     for(const QString &path : m_reader->skins())
     {
-        QListWidgetItem *item = new QListWidgetItem (path.section('/', -1));
+        item = new QListWidgetItem (path.section('/', -1));
         item->setIcon (m_reader->getPreview(path));
         item->setToolTip(tr("Archived skin") + " " + path);
         m_ui.listWidget->addItem (item);
diff --git a/src/plugins/Ui/skinned/skinreader.cpp b/src/plugins/Ui/skinned/skinreader.cpp
index b3b63d898..52127c7e0 100644
--- a/src/plugins/Ui/skinned/skinreader.cpp
+++ b/src/plugins/Ui/skinned/skinreader.cpp
@@ -25,6 +25,7 @@
 #include <QByteArray>
 #include <QApplication>
 #include <QFile>
+#include <algorithm>
 #include <qmmp/qmmp.h>
 #include "skinreader.h"
 
@@ -62,15 +63,9 @@ void SkinReader::generateThumbs()
     //clear removed skins from cache
     for(const QFileInfo &thumbFile : qAsConst(d))
     {
-        bool del = true;
-        for(const QFileInfo &fileInfo : qAsConst(f))
-        {
-            if (fileInfo.baseName () == thumbFile.baseName ())
-            {
-                del = false;
-                break;
-            }
-        }
+        bool del = std::none_of(f.cbegin(), f.cend(),
+                                [thumbFile](const QFileInfo &fileInfo){ return fileInfo.baseName() == thumbFile.baseName(); });
+
         if (del)
         {
             qDebug("SkinReader: deleting %s from cache",
@@ -82,15 +77,9 @@ void SkinReader::generateThumbs()
     //add new skins to cache
     for(const QFileInfo &fileInfo : qAsConst(f))
     {
-        bool create = true;
-        for(const QFileInfo &thumbInfo : qAsConst(d))
-        {
-            if (fileInfo.baseName () == thumbInfo.baseName ())
-            {
-                create = false;
-                break;
-            }
-        }
+        bool create = std::none_of(d.cbegin(), d.cend(),
+                                   [fileInfo](const QFileInfo &thumbInfo){ return fileInfo.baseName() == thumbInfo.baseName(); });
+
         if (create)
         {
             qDebug("SkinReader: adding %s to cache",
@@ -108,15 +97,13 @@ void SkinReader::generateThumbs()
     d = cache_dir.entryInfoList();
     for(const QFileInfo &fileInfo : qAsConst(f))
     {
-         for(const QFileInfo &thumbInfo : qAsConst(d))
-         {
-            if (fileInfo.baseName () == thumbInfo.baseName ())
-            {
-                m_previewMap.insert(fileInfo.absoluteFilePath (),
-                                    thumbInfo.absoluteFilePath ());
-                break;
-            }
-         }
+        auto it = std::find_if(d.cbegin(), d.cend(),
+                               [fileInfo](const QFileInfo &thumbInfo){ return fileInfo.baseName() == thumbInfo.baseName(); });
+
+        if(it != d.cend())
+        {
+            m_previewMap.insert(fileInfo.absoluteFilePath (), (*it).absoluteFilePath());
+        }
     }
 }
 
@@ -153,8 +140,7 @@ void SkinReader::untar(const QString &from, const QString &to, bool preview)
     m_process->start("tar", args);
     m_process->waitForFinished();
     array = m_process->readAllStandardOutput ();
-    QString str = QString(array);
-    const QStringList outputList = str.split("\n", QString::SkipEmptyParts);
+    const QStringList outputList = QString(array).split("\n", QString::SkipEmptyParts);
     for(QString str : qAsConst(outputList))
     {
         str = str.trimmed();
diff --git a/src/plugins/Ui/skinned/skinreader.h b/src/plugins/Ui/skinned/skinreader.h
index cebda0cb7..e74f1afb4 100644
--- a/src/plugins/Ui/skinned/skinreader.h
+++ b/src/plugins/Ui/skinned/skinreader.h
@@ -33,7 +33,7 @@ class SkinReader : public QObject
 {
     Q_OBJECT
 public:
-    SkinReader(QObject *parent = nullptr);
+    explicit SkinReader(QObject *parent = nullptr);
 
     ~SkinReader();
 
diff --git a/src/plugins/Ui/skinned/symboldisplay.cpp b/src/plugins/Ui/skinned/symboldisplay.cpp
index 28608b9de..a3f1436d4 100644
--- a/src/plugins/Ui/skinned/symboldisplay.cpp
+++ b/src/plugins/Ui/skinned/symboldisplay.cpp
@@ -22,13 +22,10 @@
 #include "skin.h"
 #include "symboldisplay.h"
 
-SymbolDisplay::SymbolDisplay (QWidget *parent, int digits)
-        : PixmapWidget (parent)
+SymbolDisplay::SymbolDisplay (QWidget *parent, int digits) : PixmapWidget (parent),
+    m_digits(digits)
 {
-    m_alignment = Qt::AlignRight;
     m_skin = Skin::instance();
-    m_digits  = digits;
-    m_max = 0;
     connect (m_skin, SIGNAL (skinChanged()), this, SLOT (draw()));
     draw();
     for (int i = 0; i < m_digits; ++i)
diff --git a/src/plugins/Ui/skinned/symboldisplay.h b/src/plugins/Ui/skinned/symboldisplay.h
index 4f232ae01..34dc7cac8 100644
--- a/src/plugins/Ui/skinned/symboldisplay.h
+++ b/src/plugins/Ui/skinned/symboldisplay.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2006-2013 by Ilya Kotov                                 *
+ *   Copyright (C) 2006-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -32,7 +32,7 @@ class SymbolDisplay : public PixmapWidget
 {
     Q_OBJECT
 public:
-    SymbolDisplay(QWidget *parent = nullptr, int digits = 3);
+    explicit SymbolDisplay(QWidget *parent = nullptr, int digits = 3);
 
     virtual ~SymbolDisplay();
 
@@ -49,9 +49,9 @@ private slots:
 private:
     Skin* m_skin;
     QString m_text;
-    Qt::Alignment m_alignment;
+    Qt::Alignment m_alignment = Qt::AlignRight;
     int m_digits;
-    int m_max;
+    int m_max = 0;
 };
 
 #endif
diff --git a/src/plugins/Ui/skinned/textscroller.cpp b/src/plugins/Ui/skinned/textscroller.cpp
index f2fb7cbda..ec479bb1b 100644
--- a/src/plugins/Ui/skinned/textscroller.cpp
+++ b/src/plugins/Ui/skinned/textscroller.cpp
@@ -42,9 +42,9 @@
 #define SCROLL_SEP "   *** "
 #define TITLE_FORMAT "%p%if(%p&%t, - ,)%t%if(%p,,%if(%t,,%f))%if(%l, - %l,)"
 
-TextScroller::TextScroller (QWidget *parent) : QWidget (parent)
+TextScroller::TextScroller (QWidget *parent) : QWidget (parent),
+    m_defautText(QString("Qmmp ") + Qmmp::strVersion())
 {
-    m_defautText = QString("Qmmp ") + Qmmp::strVersion();
     m_formater.setPattern(TITLE_FORMAT);
     m_core = SoundCore::instance();
     m_skin = Skin::instance();
diff --git a/src/plugins/Ui/skinned/textscroller.h b/src/plugins/Ui/skinned/textscroller.h
index 9b46adafd..d0bd7092b 100644
--- a/src/plugins/Ui/skinned/textscroller.h
+++ b/src/plugins/Ui/skinned/textscroller.h
@@ -37,7 +37,7 @@ class TextScroller : public QWidget
 {
 Q_OBJECT
 public:
-    TextScroller(QWidget *parent = nullptr);
+    explicit TextScroller(QWidget *parent = nullptr);
     virtual ~TextScroller();
 
     void setText(const QString &text);
diff --git a/src/plugins/Ui/skinned/togglebutton.cpp b/src/plugins/Ui/skinned/togglebutton.cpp
index 3e20cf18b..805a8319a 100644
--- a/src/plugins/Ui/skinned/togglebutton.cpp
+++ b/src/plugins/Ui/skinned/togglebutton.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2007-2008 by Ilya Kotov                                 *
+ *   Copyright (C) 2007-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   Based on Promoe, an XMMS2 Client                                      *
@@ -25,32 +25,29 @@
 #include "togglebutton.h"
 #include <QMouseEvent>
 
-ToggleButton::ToggleButton ( QWidget *parent,uint on_n,uint on_p,uint off_n,uint off_p )
-      : PixmapWidget ( parent )
+ToggleButton::ToggleButton(QWidget *parent,uint on_n,uint on_p,uint off_n,uint off_p) : PixmapWidget(parent),
+    m_on_n(on_n),
+    m_on_p(on_p),
+    m_off_n(off_n),
+    m_off_p(off_p)
 {
-   m_on_n = on_n;
-   m_on_p = on_p;
-   m_off_n = off_n;
-   m_off_p = off_p;
-   m_on = false;
-   skin = Skin::instance();
-   setChecked ( false );
-   connect ( skin, SIGNAL ( skinChanged() ), this, SLOT ( updateSkin() ) );
+   m_skin = Skin::instance();
+   setChecked(false);
+   connect(m_skin, SIGNAL(skinChanged()), this, SLOT(updateSkin()));
 }
 
-
 ToggleButton::~ToggleButton()
 {}
 
-bool ToggleButton::isChecked()
+bool ToggleButton::isChecked() const
 {
    return m_on;
 }
 
 void ToggleButton::updateSkin()
 {
-   //setPixmap ( skin->getButton ( name_normal ) );
-   setChecked ( m_on );
+   //setPixmap(skin->getButton(name_normal));
+   setChecked(m_on);
 }
 
 void ToggleButton::click()
@@ -60,49 +57,49 @@ void ToggleButton::click()
     emit clicked(m_on);
 }
 
-void ToggleButton::setChecked ( bool on )
+void ToggleButton::setChecked(bool on)
 {
    m_on = on;
-   if ( on )
-      setPixmap ( skin->getButton ( m_on_n ) );
+   if(on)
+      setPixmap(m_skin->getButton(m_on_n));
    else
-      setPixmap ( skin->getButton ( m_off_n ) );
+      setPixmap(m_skin->getButton(m_off_n));
 }
-void ToggleButton::mousePressEvent ( QMouseEvent* )
+void ToggleButton::mousePressEvent(QMouseEvent*)
 {
    m_cursorin = true;
    m_old_on = m_on;
-   if ( m_on )
-      setPixmap ( skin->getButton ( m_off_p ) );
+   if(m_on)
+      setPixmap(m_skin->getButton(m_off_p));
    else
-      setPixmap ( skin->getButton ( m_on_p ) );
+      setPixmap(m_skin->getButton(m_on_p));
 }
 
-void ToggleButton::mouseReleaseEvent ( QMouseEvent* )
+void ToggleButton::mouseReleaseEvent(QMouseEvent*)
 {
-   if ( m_cursorin ) {
+   if(m_cursorin) {
        m_on = !m_old_on;
-       setChecked ( m_on );
-       emit clicked( m_on );
+       setChecked(m_on);
+       emit clicked( m_on);
    } else {
        m_on = m_old_on;
-       setChecked ( m_on );
+       setChecked(m_on);
    }
 }
 
 void ToggleButton::mouseMoveEvent (QMouseEvent *e)
 {
-    if ( !m_cursorin && rect().contains(e->pos()) ) {
+    if(!m_cursorin && rect().contains(e->pos())) {
         m_cursorin = true;
-        if ( m_old_on )
-            setPixmap ( skin->getButton ( m_off_p ) );
+        if(m_old_on)
+            setPixmap(m_skin->getButton(m_off_p));
         else
-            setPixmap ( skin->getButton ( m_on_p ) );            
-    } else if ( m_cursorin && !rect().contains(e->pos()) ) {
+            setPixmap(m_skin->getButton(m_on_p));
+    } else if(m_cursorin && !rect().contains(e->pos())) {
         m_cursorin = false;
-        if ( m_old_on )
-            setPixmap ( skin->getButton ( m_on_n ) );
+        if(m_old_on)
+            setPixmap(m_skin->getButton(m_on_n));
         else
-            setPixmap ( skin->getButton ( m_off_n ) );
+            setPixmap(m_skin->getButton(m_off_n));
     }
 }
diff --git a/src/plugins/Ui/skinned/togglebutton.h b/src/plugins/Ui/skinned/togglebutton.h
index b46fd4fbc..0ddca9308 100644
--- a/src/plugins/Ui/skinned/togglebutton.h
+++ b/src/plugins/Ui/skinned/togglebutton.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2006 by Ilya Kotov                                      *
+ *   Copyright (C) 2006-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -31,10 +31,10 @@ class ToggleButton : public PixmapWidget
 {
 Q_OBJECT
 public:
-   ToggleButton( QWidget *parent, uint on_n, uint on_p, uint off_n, uint off_p );
+   ToggleButton(QWidget *parent, uint on_n, uint on_p, uint off_n, uint off_p);
    ~ToggleButton();
 
-    bool isChecked();
+    bool isChecked() const;
 
 public slots:
     void setChecked(bool);
@@ -47,10 +47,10 @@ private slots:
     void updateSkin();
 
 private:
-    Skin *skin;
+    Skin *m_skin;
     bool m_cursorin, m_old_on;
     uint m_on_n, m_on_p, m_off_n, m_off_p;
-    bool m_on;
+    bool m_on = false;
 
 protected:
     void mousePressEvent(QMouseEvent*) override;
diff --git a/src/plugins/Visual/analyzer/analyzer.cpp b/src/plugins/Visual/analyzer/analyzer.cpp
index 30708f676..75b305a86 100644
--- a/src/plugins/Visual/analyzer/analyzer.cpp
+++ b/src/plugins/Visual/analyzer/analyzer.cpp
@@ -33,14 +33,6 @@
 
 Analyzer::Analyzer (QWidget *parent) : Visual (parent)
 {
-    m_intern_vis_data = nullptr;
-    m_peaks = nullptr;
-    m_x_scale = nullptr;
-    m_rows = 0;
-    m_cols = 0;
-    m_update = false;
-    m_running = false;
-
     setWindowTitle (tr("Qmmp Analyzer"));
     setMinimumSize(2*300-30,105);
     m_timer = new QTimer (this);
@@ -234,8 +226,6 @@ void Analyzer::process()
 
     short dest_l[256];
     short dest_r[256];
-    short yl, yr;
-    int j, k, magnitude_l, magnitude_r;
 
     calc_freq (dest_l, m_left_buffer);
     calc_freq (dest_r, m_right_buffer);
@@ -244,16 +234,18 @@ void Analyzer::process()
 
     for (int i = 0; i < m_cols; i++)
     {
-        j = m_cols * 2 - i - 1; //mirror index
-        yl = yr = 0;
-        magnitude_l = magnitude_r = 0;
+        int j = m_cols * 2 - i - 1; //mirror index
+        short yl = 0;
+        short yr = 0;
+        int magnitude_l = 0;
+        int magnitude_r = 0;
 
         if(m_x_scale[i] == m_x_scale[i + 1])
         {
             yl = dest_l[i];
             yr = dest_r[i];
         }
-        for (k = m_x_scale[i]; k < m_x_scale[i + 1]; k++)
+        for (int k = m_x_scale[i]; k < m_x_scale[i + 1]; k++)
         {
             yl = qMax(dest_l[k], yl);
             yr = qMax(dest_r[k], yr);
@@ -293,12 +285,11 @@ void Analyzer::process()
 void Analyzer::draw(QPainter *p)
 {
     QBrush brush(Qt::SolidPattern);
-    int x = 0;
     int rdx = qMax(0, width() - 2 * m_cell_size.width() * m_cols);
 
     for (int j = 0; j < m_cols * 2; ++j)
     {
-        x = j * m_cell_size.width() + 1;
+        int x = j * m_cell_size.width() + 1;
         if(j >= m_cols)
             x += rdx; //correct right part position
 
diff --git a/src/plugins/Visual/analyzer/analyzer.h b/src/plugins/Visual/analyzer/analyzer.h
index 076948adb..3d77d30f1 100644
--- a/src/plugins/Visual/analyzer/analyzer.h
+++ b/src/plugins/Visual/analyzer/analyzer.h
@@ -37,7 +37,7 @@ class Analyzer : public Visual
     Q_OBJECT
 
 public:
-    Analyzer( QWidget *parent = nullptr);
+    explicit Analyzer( QWidget *parent = nullptr);
     virtual ~Analyzer();
 
 public slots:
@@ -61,17 +61,17 @@ private:
     void draw(QPainter *p);
     void createMenu();
     QTimer *m_timer;
-    double *m_intern_vis_data;
-    double *m_peaks;
-    int *m_x_scale;
+    double *m_intern_vis_data = nullptr;
+    double *m_peaks = nullptr;
+    int *m_x_scale = nullptr;
     double m_peaks_falloff;
     double m_analyzer_falloff;
     bool m_show_peaks;
     float m_left_buffer[QMMP_VISUAL_NODE_SIZE];
     float m_right_buffer[QMMP_VISUAL_NODE_SIZE];
-    int m_cols, m_rows;
-    bool m_update;
-    bool m_running;
+    int m_cols = 0, m_rows = 0;
+    bool m_update = false;
+    bool m_running = false;
     //colors
     QColor m_color1;
     QColor m_color2;
diff --git a/src/plugins/Visual/projectm/projectmwidget.h b/src/plugins/Visual/projectm/projectmwidget.h
index 7dbdc2594..d67742a07 100644
--- a/src/plugins/Visual/projectm/projectmwidget.h
+++ b/src/plugins/Visual/projectm/projectmwidget.h
@@ -35,7 +35,7 @@ class ProjectMWidget : public QOpenGLWidget
 {
     Q_OBJECT
 public:
-    ProjectMWidget(QListWidget *listWidget, QWidget *parent = nullptr);
+    explicit ProjectMWidget(QListWidget *listWidget, QWidget *parent = nullptr);
 
     ~ProjectMWidget();
 
diff --git a/src/plugins/Visual/projectm/projectmwrapper.cpp b/src/plugins/Visual/projectm/projectmwrapper.cpp
index 5078cffe2..16449a432 100644
--- a/src/plugins/Visual/projectm/projectmwrapper.cpp
+++ b/src/plugins/Visual/projectm/projectmwrapper.cpp
@@ -20,12 +20,12 @@
 
 #include "projectmwrapper.h"
 
-ProjectMWrapper::ProjectMWrapper(std::string config_file, int flags, QObject *parent) :
+ProjectMWrapper::ProjectMWrapper(const std::string &config_file, int flags, QObject *parent) :
     QObject(parent), projectM(config_file, flags)
 {
 }
 
-ProjectMWrapper::ProjectMWrapper(projectM::Settings settings, int flags, QObject *parent) :
+ProjectMWrapper::ProjectMWrapper(const projectM::Settings &settings, int flags, QObject *parent) :
     QObject(parent), projectM(settings, flags)
 {
 }
diff --git a/src/plugins/Visual/projectm/projectmwrapper.h b/src/plugins/Visual/projectm/projectmwrapper.h
index 99b226ac7..fead927ed 100644
--- a/src/plugins/Visual/projectm/projectmwrapper.h
+++ b/src/plugins/Visual/projectm/projectmwrapper.h
@@ -28,8 +28,8 @@ class ProjectMWrapper : public QObject, public projectM
 {
     Q_OBJECT
 public:
-    explicit ProjectMWrapper(std::string config_file, int flags, QObject *parent = nullptr);
-    explicit ProjectMWrapper(Settings settings, int flags, QObject *parent = nullptr);
+    explicit ProjectMWrapper(const std::string &config_file, int flags, QObject *parent = nullptr);
+    explicit ProjectMWrapper(const Settings &settings, int flags, QObject *parent = nullptr);
 
     virtual ~ProjectMWrapper();
 
diff --git a/src/qmmp/audioparameters.cpp b/src/qmmp/audioparameters.cpp
index 4af261625..4789b5014 100644
--- a/src/qmmp/audioparameters.cpp
+++ b/src/qmmp/audioparameters.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2009-2016 by Ilya Kotov                                 *
+ *   Copyright (C) 2009-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -22,30 +22,22 @@
 #include "audioparameters.h"
 
 AudioParameters::AudioParameters()
-{
-    m_srate = 0;
-    m_format = Qmmp::PCM_S16LE;
-    m_sz = 2;
-    m_precision = 16;
-}
-
-AudioParameters::AudioParameters(const AudioParameters &other)
-{
-    m_srate = other.sampleRate();
-    m_chan_map = other.channelMap();
-    m_format = other.format();
-    m_sz = other.sampleSize();
-    m_precision = other.validBitsPerSample();
-}
-
-AudioParameters::AudioParameters(quint32 srate, const ChannelMap &map, Qmmp::AudioFormat format)
-{
-    m_srate = srate;
-    m_chan_map = map;
-    m_format = format;
-    m_sz = sampleSize(format);
-    m_precision = validBitsPerSample(format);
-}
+{}
+
+AudioParameters::AudioParameters(const AudioParameters &other) : m_srate(other.sampleRate()),
+    m_chan_map(other.channelMap()),
+    m_format(other.format()),
+    m_sz(other.sampleSize()),
+    m_precision(other.validBitsPerSample())
+{}
+
+AudioParameters::AudioParameters(quint32 srate, const ChannelMap &map, Qmmp::AudioFormat format) :
+    m_srate(srate),
+    m_chan_map(map),
+    m_format(format),
+    m_sz(sampleSize(format)),
+    m_precision(validBitsPerSample(format))
+{}
 
 AudioParameters &AudioParameters::operator=(const AudioParameters &p)
 {
diff --git a/src/qmmp/audioparameters.h b/src/qmmp/audioparameters.h
index a3f992157..dab8ea3fd 100644
--- a/src/qmmp/audioparameters.h
+++ b/src/qmmp/audioparameters.h
@@ -132,11 +132,11 @@ public:
     static Qmmp::AudioFormat findAudioFormat(int bits, ByteOrder byteOrder = LittleEndian);
 
 private:
-    quint32 m_srate;
+    quint32 m_srate = 0;
     ChannelMap m_chan_map;
-    Qmmp::AudioFormat m_format;
-    int m_sz;
-    int m_precision;
+    Qmmp::AudioFormat m_format = Qmmp::PCM_S16LE;
+    int m_sz = 2;
+    int m_precision = 16;
 };
 
 #endif // AUDIOPARAMETERS_H
diff --git a/src/qmmp/channelmap.cpp b/src/qmmp/channelmap.cpp
index 92b7f86b6..1eb09aa3c 100644
--- a/src/qmmp/channelmap.cpp
+++ b/src/qmmp/channelmap.cpp
@@ -66,18 +66,18 @@ const ChannelMap ChannelMap::remaped() const
 const QString ChannelMap::toString() const
 {
     QStringList list;
-    QHash <Qmmp::ChannelPosition, QString> names;
-    names.insert(Qmmp::CHAN_NULL, "NA");
-    names.insert(Qmmp::CHAN_FRONT_LEFT, "FL");
-    names.insert(Qmmp::CHAN_FRONT_RIGHT, "FR");
-    names.insert(Qmmp::CHAN_REAR_LEFT, "RL");
-    names.insert(Qmmp::CHAN_REAR_RIGHT, "RR");
-    names.insert(Qmmp::CHAN_FRONT_CENTER, "FC");
-    names.insert(Qmmp::CHAN_REAR_CENTER, "RC");
-    names.insert(Qmmp::CHAN_LFE, "LFE");
-    names.insert(Qmmp::CHAN_SIDE_LEFT, "SL");
-    names.insert(Qmmp::CHAN_SIDE_RIGHT, "SR");
-
+    QHash <Qmmp::ChannelPosition, QString> names = {
+        { Qmmp::CHAN_NULL, "NA" },
+        { Qmmp::CHAN_FRONT_LEFT, "FL" },
+        { Qmmp::CHAN_FRONT_RIGHT, "FR" },
+        { Qmmp::CHAN_REAR_LEFT, "RL" },
+        { Qmmp::CHAN_REAR_RIGHT, "RR" },
+        { Qmmp::CHAN_FRONT_CENTER, "FC" },
+        { Qmmp::CHAN_REAR_CENTER, "RC" },
+        { Qmmp::CHAN_LFE, "LFE" },
+        { Qmmp::CHAN_SIDE_LEFT, "SL" },
+        { Qmmp::CHAN_SIDE_RIGHT, "SR" }
+    };
 
     for(const Qmmp::ChannelPosition channel : qAsConst(*this))
     {
diff --git a/src/qmmp/channelmap.h b/src/qmmp/channelmap.h
index 2bc232916..7cbb35975 100644
--- a/src/qmmp/channelmap.h
+++ b/src/qmmp/channelmap.h
@@ -28,7 +28,7 @@ class QMMP_EXPORT ChannelMap : public QList<Qmmp::ChannelPosition>
 {
 public:
     ChannelMap();
-    ChannelMap(int channels);
+    explicit ChannelMap(int channels);
 
     int mask() const;
     const ChannelMap remaped() const;
diff --git a/src/qmmp/emptyinputsource.cpp b/src/qmmp/emptyinputsource.cpp
index e9a082d38..1266c3c23 100644
--- a/src/qmmp/emptyinputsource.cpp
+++ b/src/qmmp/emptyinputsource.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2009 by Ilya Kotov                                      *
+ *   Copyright (C) 2009-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -21,11 +21,9 @@
 #include "emptyinputsource_p.h"
 
 EmptyInputSource::EmptyInputSource(const QString &url, QObject *parent) : InputSource(url,parent)
-{
-    m_ok = false;
-}
+{}
 
-QIODevice *EmptyInputSource::ioDevice()
+QIODevice *EmptyInputSource::ioDevice() const
 {
     return nullptr;
 }
@@ -38,7 +36,7 @@ bool EmptyInputSource::initialize()
     return m_ok;
 }
 
-bool EmptyInputSource::isReady()
+bool EmptyInputSource::isReady() const
 {
     return m_ok;
 }
diff --git a/src/qmmp/emptyinputsource_p.h b/src/qmmp/emptyinputsource_p.h
index 874a8f83a..8c085269d 100644
--- a/src/qmmp/emptyinputsource_p.h
+++ b/src/qmmp/emptyinputsource_p.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2009 by Ilya Kotov                                      *
+ *   Copyright (C) 2009-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -30,14 +30,14 @@ class EmptyInputSource : public InputSource
 {
 Q_OBJECT
 public:
-    EmptyInputSource(const QString &path, QObject *parent = nullptr);
+    explicit EmptyInputSource(const QString &path, QObject *parent = nullptr);
 
-    QIODevice *ioDevice() override;
+    QIODevice *ioDevice() const override;
     bool initialize() override;
-    bool isReady() override;
+    bool isReady() const override;
 
 private:
-    bool m_ok;
+    bool m_ok = false;
 };
 
 #endif // EMPTYINPUTSOURCE_P_H
diff --git a/src/qmmp/fileinputsource.cpp b/src/qmmp/fileinputsource.cpp
index 4bff28707..3f331fe93 100644
--- a/src/qmmp/fileinputsource.cpp
+++ b/src/qmmp/fileinputsource.cpp
@@ -26,7 +26,7 @@ FileInputSource::FileInputSource(const QString &url, QObject *parent) : InputSou
     m_file = new QFile(url, this);
 }
 
-QIODevice *FileInputSource::ioDevice()
+QIODevice *FileInputSource::ioDevice() const
 {
     return m_file;
 }
@@ -37,7 +37,7 @@ bool FileInputSource::initialize()
     return true;
 }
 
-bool FileInputSource::isReady()
+bool FileInputSource::isReady() const
 {
     return m_file->isOpen();
 }
diff --git a/src/qmmp/fileinputsource_p.h b/src/qmmp/fileinputsource_p.h
index d8e14e093..8ce763e75 100644
--- a/src/qmmp/fileinputsource_p.h
+++ b/src/qmmp/fileinputsource_p.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2009 by Ilya Kotov                                      *
+ *   Copyright (C) 2009-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -32,11 +32,11 @@ class FileInputSource : public InputSource
 {
 Q_OBJECT
 public:
-    FileInputSource(const QString &path, QObject *parent = nullptr);
+    explicit FileInputSource(const QString &path, QObject *parent = nullptr);
 
-    QIODevice *ioDevice() override;
+    QIODevice *ioDevice() const override;
     bool initialize() override;
-    bool isReady() override;
+    bool isReady() const override;
 
 private:
     QFile *m_file;
diff --git a/src/qmmp/inputsource.cpp b/src/qmmp/inputsource.cpp
index ff6303cc7..8403c4596 100644
--- a/src/qmmp/inputsource.cpp
+++ b/src/qmmp/inputsource.cpp
@@ -20,21 +20,18 @@
 
 #include <QFile>
 #include <QDir>
+#include <algorithm>
 #include "qmmpplugincache_p.h"
 #include "qmmp.h"
 #include "fileinputsource_p.h"
 #include "emptyinputsource_p.h"
 #include "inputsource.h"
 
-InputSource::InputSource(const QString &source, QObject *parent) : QObject(parent)
-{
-    m_path = source;
-    m_offset = -1;
-    m_hasMetaData = false;
-    m_hasStreamInfo = false;
-}
+InputSource::InputSource(const QString &source, QObject *parent) : QObject(parent),
+    m_path(source)
+{}
 
-bool InputSource::isWaiting()
+bool InputSource::isWaiting() const
 {
     return false;
 }
@@ -170,12 +167,9 @@ QList<InputSourceFactory *> InputSource::enabledFactories()
 QString InputSource::file(const InputSourceFactory *factory)
 {
     loadPlugins();
-    for(const QmmpPluginCache *item : qAsConst(*m_cache))
-    {
-        if(item->shortName() == factory->properties().shortName)
-            return item->file();
-    }
-    return QString();
+    auto it = std::find_if(m_cache->cbegin(), m_cache->cend(),
+                           [factory](QmmpPluginCache *item) { return item->shortName() == factory->properties().shortName; } );
+    return it == m_cache->cend() ? QString() : (*it)->file();
 }
 
 QStringList InputSource::protocols()
diff --git a/src/qmmp/inputsource.h b/src/qmmp/inputsource.h
index c4da56d37..6caa73b55 100644
--- a/src/qmmp/inputsource.h
+++ b/src/qmmp/inputsource.h
@@ -44,12 +44,12 @@ public:
      * @param path Input source path or url.
      * @param parent Parent object.
      */
-    InputSource(const QString &path, QObject *parent = nullptr);
+    explicit InputSource(const QString &path, QObject *parent = nullptr);
     /*!
      * Returns QIODevice-based object for I/O operations.
      * Subclass shoud reimplement this function.
      */
-    virtual QIODevice *ioDevice() = 0;
+    virtual QIODevice *ioDevice() const = 0;
     /*!
      * Prepares input data source for usage.
      * Subclass shoud reimplement this function.
@@ -58,13 +58,13 @@ public:
     /*!
      * Returns \b true if transport is ready for usage; otherwise returns \b false.
      */
-    virtual bool isReady() = 0;
+    virtual bool isReady() const = 0;
     /*!
      * Returns \b true if the transport is waiting more data; otherwise returns \b false.
      * Reader should wait until this function returns \b false.
      * Default implementation allways returns \b false.
      */
-    virtual bool isWaiting();
+    virtual bool isWaiting() const;
     /*!
      * Returns content type of the input stream. Default implementation returns empty string.
      */
@@ -182,11 +182,11 @@ signals:
 
 private:
     QString m_path;
-    qint64 m_offset;
+    qint64 m_offset = -1;
     QMap<Qmmp::MetaData, QString> m_metaData;
     QMap<Qmmp::TrackProperty, QString> m_properties;
     QHash<QString, QString> m_streamInfo;
-    bool m_hasMetaData, m_hasStreamInfo;
+    bool m_hasMetaData = false, m_hasStreamInfo = false;
     static void loadPlugins();
     static QList<QmmpPluginCache*> *m_cache;
     static QStringList m_disabledNames;
diff --git a/src/qmmp/qmmpplugincache.cpp b/src/qmmp/qmmpplugincache.cpp
index 6b9f83508..2f05c9b36 100644
--- a/src/qmmp/qmmpplugincache.cpp
+++ b/src/qmmp/qmmpplugincache.cpp
@@ -33,14 +33,6 @@
 
 QmmpPluginCache::QmmpPluginCache(const QString &file, QSettings *settings)
 {
-    m_error = false;
-    m_instance = nullptr;
-    m_decoderFactory = nullptr;
-    m_outputFactory = nullptr;
-    m_engineFactory = nullptr;
-    m_effectFactory = nullptr;
-    m_inputSourceFactory = nullptr;
-    m_priority = 0;
     bool update = false;
     QFileInfo info(file);
     m_path = info.QFileInfo::canonicalFilePath();
diff --git a/src/qmmp/qmmpplugincache_p.h b/src/qmmp/qmmpplugincache_p.h
index 4dfb938b4..3d6f581e6 100644
--- a/src/qmmp/qmmpplugincache_p.h
+++ b/src/qmmp/qmmpplugincache_p.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2013 by Ilya Kotov                                      *
+ *   Copyright (C) 2013-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -57,14 +57,14 @@ private:
     void loadTranslation(const QString &translation);
     QString m_path;
     QString m_shortName;
-    bool m_error;
-    QObject *m_instance;
-    DecoderFactory *m_decoderFactory;
-    OutputFactory *m_outputFactory;
-    EngineFactory *m_engineFactory;
-    EffectFactory *m_effectFactory;
-    InputSourceFactory *m_inputSourceFactory;
-    int m_priority;
+    bool m_error = false;
+    QObject *m_instance = nullptr;
+    DecoderFactory *m_decoderFactory = nullptr;
+    OutputFactory *m_outputFactory = nullptr;
+    EngineFactory *m_engineFactory = nullptr;
+    EffectFactory *m_effectFactory = nullptr;
+    InputSourceFactory *m_inputSourceFactory = nullptr;
+    int m_priority = 0;
 };
 
 #endif // QMMPPLUGINCACHE_P_H
diff --git a/src/qmmp/visualbuffer.cpp b/src/qmmp/visualbuffer.cpp
index d9baa9951..e6b046338 100644
--- a/src/qmmp/visualbuffer.cpp
+++ b/src/qmmp/visualbuffer.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2017 by Ilya Kotov                                      *
+ *   Copyright (C) 2017-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -44,11 +44,7 @@ static inline void stereo_from_multichannel(float *l,
 }
 
 VisualBuffer::VisualBuffer()
-{
-    m_take_index = 0;
-    m_add_index = 0;
-    m_elapsed = 0;
-}
+{}
 
 void VisualBuffer::add(float *pcm, int samples, int channels, qint64 ts, qint64 delay)
 {
diff --git a/src/qmmp/visualbuffer_p.h b/src/qmmp/visualbuffer_p.h
index 4a6841379..a6622cdc9 100644
--- a/src/qmmp/visualbuffer_p.h
+++ b/src/qmmp/visualbuffer_p.h
@@ -30,15 +30,9 @@
 class VisualNode
 {
 public:
-    float data[2][512];
-    bool used;
-    qint64 ts;
-
-    VisualNode()
-    {
-        used = false;
-        ts = 0;
-    }
+    float data[2][512] = { 0 };
+    bool used = false;
+    qint64 ts = 0;
 };
 
 class VisualBuffer
@@ -53,9 +47,9 @@ public:
 
 private:
     VisualNode m_buffer[VISUAL_BUFFER_SIZE];
-    qint64 m_elapsed;
-    int m_take_index;
-    int m_add_index;
+    qint64 m_elapsed = 0;
+    int m_take_index = 0;
+    int m_add_index = 0;
     QElapsedTimer m_time;
     QMutex m_mutex;
 
diff --git a/src/qmmpui/addurldialog_p.h b/src/qmmpui/addurldialog_p.h
index d9d4a3d78..005915ed1 100644
--- a/src/qmmpui/addurldialog_p.h
+++ b/src/qmmpui/addurldialog_p.h
@@ -44,7 +44,7 @@ private slots:
     void onFinished(bool ok, const QString &message);
 
 private:
-    AddUrlDialog(QWidget *parent);
+    explicit AddUrlDialog(QWidget *parent);
     ~AddUrlDialog();
     void accept() override;
     void setModel(PlayListModel*);
diff --git a/src/qmmpui/detailsdialog.cpp b/src/qmmpui/detailsdialog.cpp
index fe0625b17..0cc798c94 100644
--- a/src/qmmpui/detailsdialog.cpp
+++ b/src/qmmpui/detailsdialog.cpp
@@ -35,7 +35,7 @@
 #include "detailsdialog.h"
 
 DetailsDialog::DetailsDialog(QList<PlayListTrack *> tracks, QWidget *parent)
-        : QDialog(parent)
+        : QDialog(parent), m_tracks(tracks)
 {
     m_ui = new Ui::DetailsDialog;
     m_ui->setupUi(this);
@@ -44,9 +44,6 @@ DetailsDialog::DetailsDialog(QList<PlayListTrack *> tracks, QWidget *parent)
     m_ui->directoryButton->setIcon(QApplication::style()->standardIcon(QStyle::SP_DirOpenIcon));
     m_ui->nextButton->setIcon(QApplication::style()->standardIcon(QStyle::SP_ArrowRight));
     m_ui->prevButton->setIcon(QApplication::style()->standardIcon(QStyle::SP_ArrowLeft));
-    m_metaDataModel = nullptr;
-    m_page = 0;
-    m_tracks = tracks;
     updatePage();
     on_tabWidget_currentChanged(0);
 }
diff --git a/src/qmmpui/detailsdialog.h b/src/qmmpui/detailsdialog.h
index 725c6b817..c4c5e04e9 100644
--- a/src/qmmpui/detailsdialog.h
+++ b/src/qmmpui/detailsdialog.h
@@ -48,7 +48,7 @@ public:
      * @param tracks a list of tracks which should be used.
      * @param parent Parent widget.
      */
-    DetailsDialog(QList<PlayListTrack *> tracks, QWidget *parent = nullptr);
+    explicit DetailsDialog(QList<PlayListTrack *> tracks, QWidget *parent = nullptr);
     /*!
      * Destructor.
      */
@@ -68,10 +68,10 @@ private:
     void printInfo();
     QString formatRow(const QString &key, const QString &value) const;
     QString formatRow(const MetaDataItem &item) const;
-    MetaDataModel *m_metaDataModel;
+    MetaDataModel *m_metaDataModel = nullptr;
     QList<PlayListTrack *> m_tracks;
     TrackInfo m_info;
-    int m_page;
+    int m_page = 0;
 };
 
 #endif
diff --git a/src/qmmpui/filedialog.cpp b/src/qmmpui/filedialog.cpp
index 5d2915b6e..ab67d6889 100644
--- a/src/qmmpui/filedialog.cpp
+++ b/src/qmmpui/filedialog.cpp
@@ -24,6 +24,7 @@
 #include <QPluginLoader>
 #include <QMetaObject>
 #include <QLibrary>
+#include <algorithm>
 #include <qmmp/qmmp.h>
 #include "qmmpuiplugincache_p.h"
 #include "filedialog.h"
@@ -85,12 +86,9 @@ bool FileDialog::isEnabled(const FileDialogFactory *factory)
 QString FileDialog::file(const FileDialogFactory *factory)
 {
     loadPlugins();
-    for(const QmmpUiPluginCache *item : qAsConst(*m_cache))
-    {
-        if(item->shortName() == factory->properties().shortName)
-            return item->file();
-    }
-    return QString();
+    auto it = std::find_if(m_cache->cbegin(), m_cache->cend(),
+                           [factory] (QmmpUiPluginCache *item){ return item->shortName() == factory->properties().shortName; } );
+    return it == m_cache->cend() ? QString() : (*it)->file();
 }
 
 QString FileDialog::getExistingDirectory(QWidget *parent,
@@ -167,14 +165,11 @@ FileDialog* FileDialog::instance()
 
     QSettings settings (Qmmp::configFile(), QSettings::IniFormat);
     QString name = settings.value("FileDialog", "qt_dialog").toString();
-    for(QmmpUiPluginCache *item : qAsConst(*m_cache))
-    {
-        if(item->shortName() == name)
-        {
-            selected = item->fileDialogFactory();
-            break;
-        }
-    }
+
+    auto it = std::find_if(m_cache->cbegin(), m_cache->cend(),
+                           [name] (QmmpUiPluginCache *item){ return item->shortName() == name; } );
+    if(it != m_cache->cend())
+        selected = (*it)->fileDialogFactory();
 
     if(!selected)
         selected = m_cache->at(0)->fileDialogFactory();
diff --git a/src/qmmpui/general.cpp b/src/qmmpui/general.cpp
index 0ca8e2fb0..592bdf894 100644
--- a/src/qmmpui/general.cpp
+++ b/src/qmmpui/general.cpp
@@ -100,12 +100,9 @@ QList<GeneralFactory *> General::enabledFactories()
 QString General::file(const GeneralFactory *factory)
 {
     loadPlugins();
-    for(const QmmpUiPluginCache *item : qAsConst(*m_cache))
-    {
-        if(item->shortName() == factory->properties().shortName)
-            return item->file();
-    }
-    return QString();
+    auto it = std::find_if(m_cache->cbegin(), m_cache->cend(),
+                           [factory] (QmmpUiPluginCache *item){ return item->shortName() == factory->properties().shortName; } );
+    return it == m_cache->cend() ? QString() : (*it)->file();
 }
 
 void General::setEnabled(GeneralFactory* factory, bool enable)
diff --git a/src/qmmpui/groupedcontainer.cpp b/src/qmmpui/groupedcontainer.cpp
index 24193261c..68c8164c6 100644
--- a/src/qmmpui/groupedcontainer.cpp
+++ b/src/qmmpui/groupedcontainer.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2013-2015 by Ilya Kotov                                 *
+ *   Copyright (C) 2013-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -26,9 +26,7 @@
 #endif
 
 GroupedContainer::GroupedContainer()
-{
-    m_update = true;
-}
+{}
 
 GroupedContainer::~GroupedContainer()
 {
@@ -70,11 +68,9 @@ void GroupedContainer::addTrack(PlayListTrack *track)
 
 void GroupedContainer::addTracks(const QList<PlayListTrack *> &tracks)
 {
-    bool found = false;
-
     for(int i = 0; i < tracks.count(); ++i)
     {
-        found = false;
+        bool found = false;
         for(int j = m_groups.count() - 1; j >= 0; --j)
         {
             if(m_groups.at(j)->formattedTitle() == tracks.at(i)->groupName())
diff --git a/src/qmmpui/groupedcontainer_p.h b/src/qmmpui/groupedcontainer_p.h
index 3a0e1d0b6..ca7178c67 100644
--- a/src/qmmpui/groupedcontainer_p.h
+++ b/src/qmmpui/groupedcontainer_p.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2013-2015 by Ilya Kotov                                 *
+ *   Copyright (C) 2013-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -69,7 +69,7 @@ private:
     QList<PlayListGroup *> m_groups;
 
     mutable QList<PlayListItem *> m_items;
-    mutable bool m_update;
+    mutable bool m_update = true;
 
 };
 
diff --git a/src/qmmpui/jumptotrackdialog_p.h b/src/qmmpui/jumptotrackdialog_p.h
index 2ea9b677b..e28b22104 100644
--- a/src/qmmpui/jumptotrackdialog_p.h
+++ b/src/qmmpui/jumptotrackdialog_p.h
@@ -41,7 +41,7 @@ class JumpToTrackDialog : public QDialog, private Ui::JumpToTrackDialog
     Q_OBJECT
 
 public:
-    JumpToTrackDialog(PlayListModel *model, QWidget* parent = nullptr);
+    explicit JumpToTrackDialog(PlayListModel *model, QWidget* parent = nullptr);
     ~JumpToTrackDialog();
     void refresh();
 
diff --git a/src/qmmpui/metadataformatter.cpp b/src/qmmpui/metadataformatter.cpp
index ebc4cad38..0b58bd6a1 100644
--- a/src/qmmpui/metadataformatter.cpp
+++ b/src/qmmpui/metadataformatter.cpp
@@ -609,59 +609,59 @@ QList<MetaDataFormatter::Node> MetaDataFormatter::compile(const QString &expr)
     {
         if((*i) == QChar('%'))
         {
-            i++;
+            ++i;
             if(i == expr.constEnd())
                 continue;
 
             if(parseDir(&nodes, &i, expr.constEnd()))
             {
-                i++;
+                ++i;
                 continue;
             }
 
             if(parseField(&nodes, &i, expr.constEnd()))
             {
-                i++;
+                ++i;
                 continue;
             }
 
             if(parseProperty(&nodes, &i, expr.constEnd()))
             {
-                i++;
+                ++i;
                 continue;
             }
 
             if(parseIf(&nodes, &i, expr.constEnd()))
             {
-                i++;
+                ++i;
                 continue;
             }
             continue;
         }
         else if((*i) == QChar('&'))
         {
-            i++;
+            ++i;
             Node node;
             node.command = Node::AND_OPERATOR;
             nodes.append(node);
         }
         else if((*i) == QChar('|'))
         {
-            i++;
+            ++i;
             Node node;
             node.command = Node::OR_OPERATOR;
             nodes.append(node);
         }
         else if((*i) == QChar('\\'))
         {
-            i++;
+            ++i;
             parseEscape(&nodes, &i, expr.constEnd());
-            i++;
+            ++i;
         }
         else
         {
             parseText(&nodes, &i, expr.constEnd());
-            i++;
+            ++i;
         }
     }
 
diff --git a/src/qmmpui/playlistdownloader.cpp b/src/qmmpui/playlistdownloader.cpp
index cc71eebd3..57ac8f6e4 100644
--- a/src/qmmpui/playlistdownloader.cpp
+++ b/src/qmmpui/playlistdownloader.cpp
@@ -26,9 +26,9 @@
 #include "playlistparser.h"
 #include "playlistdownloader.h"
 
-PlayListDownloader::PlayListDownloader(QObject *parent) : QObject(parent)
+PlayListDownloader::PlayListDownloader(QObject *parent) : QObject(parent),
+    m_ua(QString("qmmp/%1").arg(Qmmp::strVersion()).toLatin1())
 {
-    m_ua = QString("qmmp/%1").arg(Qmmp::strVersion()).toLatin1();
     m_manager = new QNetworkAccessManager(this);
     connect(m_manager, SIGNAL(finished (QNetworkReply *)), SLOT(readResponse(QNetworkReply *)));
     //load global proxy settings
diff --git a/src/qmmpui/playlistgroup.cpp b/src/qmmpui/playlistgroup.cpp
index cd2080762..d9f6d44fa 100644
--- a/src/qmmpui/playlistgroup.cpp
+++ b/src/qmmpui/playlistgroup.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2013-2014 by Ilya Kotov                                 *
+ *   Copyright (C) 2013-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -20,10 +20,8 @@
 
 #include "playlistgroup.h"
 
-PlayListGroup::PlayListGroup(const QString &name)
-{
-    m_name = name;
-}
+PlayListGroup::PlayListGroup(const QString &name) : m_name(name)
+{}
 
 PlayListGroup::~PlayListGroup()
 {
diff --git a/src/qmmpui/playlistgroup.h b/src/qmmpui/playlistgroup.h
index a6ce2921c..59a177d6a 100644
--- a/src/qmmpui/playlistgroup.h
+++ b/src/qmmpui/playlistgroup.h
@@ -37,7 +37,7 @@ public:
      * Constructor.
      * @param formattedTitle Title of the group.
      */
-    PlayListGroup(const QString &formattedTitle);
+    explicit PlayListGroup(const QString &formattedTitle);
     /*!
      * Object destructor.
      */
diff --git a/src/qmmpui/playlistmanager.cpp b/src/qmmpui/playlistmanager.cpp
index 48480a299..3b128745a 100644
--- a/src/qmmpui/playlistmanager.cpp
+++ b/src/qmmpui/playlistmanager.cpp
@@ -47,23 +47,27 @@ PlayListManager::PlayListManager(QObject *parent) : QObject(parent)
     m_timer->setSingleShot(true);
     connect(m_timer, SIGNAL(timeout()), SLOT(writePlayLists()));
     //key names
-    m_metaKeys.insert("title", Qmmp::TITLE);
-    m_metaKeys.insert("artist", Qmmp::ARTIST);
-    m_metaKeys.insert("albumartist", Qmmp::ALBUMARTIST);
-    m_metaKeys.insert("album", Qmmp::ALBUM);
-    m_metaKeys.insert("comment", Qmmp::COMMENT);
-    m_metaKeys.insert("genre", Qmmp::GENRE);
-    m_metaKeys.insert("composer", Qmmp::COMPOSER);
-    m_metaKeys.insert("year", Qmmp::YEAR);
-    m_metaKeys.insert("track", Qmmp::TRACK);
-    m_metaKeys.insert("disk", Qmmp::DISCNUMBER);
-    m_propKeys.insert("bitrate", Qmmp::BITRATE);
-    m_propKeys.insert("samplerate", Qmmp::SAMPLERATE);
-    m_propKeys.insert("channels", Qmmp::CHANNELS);
-    m_propKeys.insert("bits_per_sample", Qmmp::BITS_PER_SAMPLE);
-    m_propKeys.insert("format_name", Qmmp::FORMAT_NAME);
-    m_propKeys.insert("decoder", Qmmp::DECODER);
-    m_propKeys.insert("file_size", Qmmp::FILE_SIZE);
+    m_metaKeys = {
+        { "title", Qmmp::TITLE },
+        { "artist", Qmmp::ARTIST },
+        { "albumartist", Qmmp::ALBUMARTIST },
+        { "album", Qmmp::ALBUM },
+        { "comment", Qmmp::COMMENT },
+        { "genre", Qmmp::GENRE },
+        { "composer", Qmmp::COMPOSER },
+        { "year", Qmmp::YEAR },
+        { "track", Qmmp::TRACK },
+        { "disk", Qmmp::DISCNUMBER }
+    };
+    m_propKeys = {
+        { "bitrate", Qmmp::BITRATE },
+        { "samplerate", Qmmp::SAMPLERATE },
+        { "channels", Qmmp::CHANNELS },
+        { "bits_per_sample", Qmmp::BITS_PER_SAMPLE },
+        { "format_name", Qmmp::FORMAT_NAME },
+        { "decoder", Qmmp::DECODER },
+        { "file_size", Qmmp::FILE_SIZE }
+    };
     readPlayLists(); //read playlists
 }
 
@@ -266,7 +270,7 @@ void PlayListManager::readPlayLists()
     Qmmp::MetaData metaKey;
     Qmmp::TrackProperty propKey;
     QString line, key, value;
-    int s = 0, current = 0, pl = 0;
+    int current = 0, pl = 0;
     QList <PlayListTrack *> tracks;
     QFile file(Qmmp::configDir() + "/playlist.txt");
     file.open(QIODevice::ReadOnly);
@@ -278,7 +282,8 @@ void PlayListManager::readPlayLists()
     while (!buffer.atEnd())
     {
         line = QString::fromUtf8(buffer.readLine().constData()).trimmed();
-        if ((s = line.indexOf("=")) < 0)
+        int s = line.indexOf("=");
+        if (s < 0)
             continue;
 
         key = line.left(s);
diff --git a/src/qmmpui/playlistmanager.h b/src/qmmpui/playlistmanager.h
index 7298b78a9..5352eef43 100644
--- a/src/qmmpui/playlistmanager.h
+++ b/src/qmmpui/playlistmanager.h
@@ -41,7 +41,7 @@ public:
      * Constructor.
      * @param parent Parent object.
      */
-    PlayListManager(QObject *parent);
+    explicit PlayListManager(QObject *parent);
     /*!
      * Destructor.
      */
diff --git a/src/qmmpui/playlistmodel.cpp b/src/qmmpui/playlistmodel.cpp
index 3b5ae17ed..9c44acc3b 100644
--- a/src/qmmpui/playlistmodel.cpp
+++ b/src/qmmpui/playlistmodel.cpp
@@ -20,6 +20,7 @@
 #include <QWidget>
 #include <QtAlgorithms>
 #include <QTextStream>
+#include <algorithm>
 #include <time.h>
 #include <qmmp/metadatamanager.h>
 #include "metadatahelper_p.h"
@@ -39,14 +40,11 @@
 #define INVALID_INDEX -1
 
 PlayListModel::PlayListModel(const QString &name, QObject *parent)
-        : QObject(parent) , m_selection()
+    : QObject(parent) , m_name(name)
 {
     qsrand(time(nullptr));
     m_ui_settings = QmmpUiSettings::instance();
-    m_total_duration = 0;
-    m_current = 0;
-    m_stop_track = nullptr;
-    m_name = name;
+
     m_loader = new FileLoader(this);
     m_task = new PlayListTask(this);
     if(m_ui_settings->isGroupsEnabled())
@@ -728,11 +726,8 @@ void PlayListModel::moveItems(int from, int to)
     if(selected_indexes.isEmpty())
         return;
 
-    for(const int &i : qAsConst(selected_indexes)) //do no move groups
-    {
-        if(!isTrack(i))
-            return;
-    }
+    if(std::any_of(selected_indexes.cbegin(), selected_indexes.cend(), [this](int i){ return !isTrack(i); }))
+        return;
 
     if (bottommostInSelection(from) == INVALID_INDEX ||
             from == INVALID_INDEX ||
@@ -959,7 +954,7 @@ void PlayListModel::onTaskFinished()
             || m_task->type() == PlayListTask::REFRESH)
     {
         PlayListTrack *prev_current_track = m_current_track;
-        bool prev_count = m_container->count();
+        int prev_count = m_container->count();
 
         m_container->replaceTracks(m_task->takeResults(&m_current_track));
 
diff --git a/src/qmmpui/playlistmodel.h b/src/qmmpui/playlistmodel.h
index 11b8c34ca..d4e177714 100644
--- a/src/qmmpui/playlistmodel.h
+++ b/src/qmmpui/playlistmodel.h
@@ -48,14 +48,6 @@ class PlayListTask;
 struct SimpleSelection
 {
     /*!
-     * Constructs an empty selection model.
-     */
-    SimpleSelection()
-    {
-        m_bottom = -1;
-        m_top = 1;
-    }
-    /*!
      * Returns \p true if this selection is valid; otherwise returns returns \p false.
      */
     inline bool isValid()const
@@ -76,8 +68,8 @@ struct SimpleSelection
     {
         return m_bottom - m_top + 1;
     }
-    int m_bottom;               /*!< Bottom of the selection */
-    int m_top;                  /*!< Top of the selection   */
+    int m_bottom = -1;              /*!< Bottom of the selection */
+    int m_top = 1;                  /*!< Top of the selection   */
     QList<int> m_selected_indexes;  /*!< Selected items numbers */
 };
 /*! @brief The PlayListModel class provides a data model for the playlist.
@@ -109,7 +101,7 @@ public:
      * @param name Playlist name.
      * @param parent QObject parent
      */
-    PlayListModel(const QString &name, QObject *parent = nullptr);
+    explicit PlayListModel(const QString &name, QObject *parent = nullptr);
     /*!
      * Object destructor.
      */
@@ -594,13 +586,13 @@ private slots:
     void onTaskFinished();
 
 private:
-    PlayListTrack* m_current_track;
-    PlayListTrack* m_stop_track;
-    int m_current;
+    PlayListTrack* m_current_track = nullptr;
+    PlayListTrack* m_stop_track = nullptr;
+    int m_current = 0;
     SimpleSelection m_selection;  /*!< This flyweight object represents current selection. */
     QQueue <PlayListTrack*> m_queued_songs; /*!< Songs in play queue. */
     PlayState* m_play_state; /*!< Current playing state (Normal or Shuffle) */
-    qint64 m_total_duration;
+    qint64 m_total_duration = 0;
     FileLoader *m_loader;
     QString m_name;
     PlayListContainer *m_container;
diff --git a/src/qmmpui/playlistparser.cpp b/src/qmmpui/playlistparser.cpp
index 6cf3dbadd..2aac76bda 100644
--- a/src/qmmpui/playlistparser.cpp
+++ b/src/qmmpui/playlistparser.cpp
@@ -23,6 +23,7 @@
 #include <QList>
 #include <QDir>
 #include <QApplication>
+#include <algorithm>
 #include <qmmp/qmmp.h>
 #include "playlistformat.h"
 #include "playlistparser.h"
@@ -72,12 +73,9 @@ bool PlayListParser::isPlayList(const QString &url)
 PlayListFormat *PlayListParser::findByMime(const QString &mime)
 {
     loadFormats();
-    for(PlayListFormat *format : qAsConst(*m_formats))
-    {
-        if(format->properties().contentTypes.contains(mime))
-            return format;
-    }
-    return nullptr;
+    auto it = std::find_if(m_formats->cbegin(), m_formats->cend(),
+                           [mime](PlayListFormat *format) { return format->properties().contentTypes.contains(mime); } );
+    return it == m_formats->cend() ? nullptr : *it;
 }
 
 PlayListFormat *PlayListParser::findByPath(const QString &filePath)
@@ -161,12 +159,9 @@ QList<PlayListTrack *> PlayListParser::loadPlaylist(const QString &f_name)
 
 QList<PlayListTrack *> PlayListParser::loadPlaylist(const QString &fmt, const QByteArray &content)
 {
-    for(PlayListFormat *p : qAsConst(*m_formats))
-    {
-        if(p->properties().shortName == fmt)
-            return p->decode(content);
-    }
-    return QList<PlayListTrack *>();
+    auto it = std::find_if(m_formats->cbegin(), m_formats->cend(),
+                           [fmt](PlayListFormat *format) { return format->properties().shortName == fmt; } );
+    return it == m_formats->cend() ? QList<PlayListTrack *>() : (*it)->decode(content);
 }
 
 void PlayListParser::loadFormats()
diff --git a/src/qmmpui/playlisttask.cpp b/src/qmmpui/playlisttask.cpp
index 9933476a7..0ff0eecc2 100644
--- a/src/qmmpui/playlisttask.cpp
+++ b/src/qmmpui/playlisttask.cpp
@@ -112,24 +112,19 @@ static bool _filenameGreaterComparator(TrackField* s1, TrackField* s2)
 
 PlayListTask::PlayListTask(QObject *parent) : QThread(parent)
 {
-    m_reverted = true;
-    m_align_groups = false;
-    m_current_track = nullptr;
-    m_column = 0;
-    m_task = EMPTY;
-    m_sort_mode = PlayListModel::TITLE;
-
-    m_sort_keys.insert(PlayListModel::TITLE, Qmmp::TITLE);
-    m_sort_keys.insert(PlayListModel::DISCNUMBER, Qmmp::DISCNUMBER);
-    m_sort_keys.insert(PlayListModel::ALBUM, Qmmp::ALBUM);
-    m_sort_keys.insert(PlayListModel::ARTIST, Qmmp::ARTIST);
-    m_sort_keys.insert(PlayListModel::ALBUMARTIST, Qmmp::ALBUMARTIST);
-    m_sort_keys.insert(PlayListModel::FILENAME, Qmmp::UNKNOWN);
-    m_sort_keys.insert(PlayListModel::PATH_AND_FILENAME, Qmmp::UNKNOWN);
-    m_sort_keys.insert(PlayListModel::DATE, Qmmp::YEAR);
-    m_sort_keys.insert(PlayListModel::TRACK, Qmmp::TRACK);
-    m_sort_keys.insert(PlayListModel::FILE_CREATION_DATE, Qmmp::UNKNOWN);
-    m_sort_keys.insert(PlayListModel::FILE_MODIFICATION_DATE, Qmmp::UNKNOWN);
+    m_sort_keys = {
+        { PlayListModel::TITLE, Qmmp::TITLE },
+        { PlayListModel::DISCNUMBER, Qmmp::DISCNUMBER },
+        { PlayListModel::ALBUM, Qmmp::ALBUM },
+        { PlayListModel::ARTIST, Qmmp::ARTIST },
+        { PlayListModel::ALBUMARTIST, Qmmp::ALBUMARTIST },
+        { PlayListModel::FILENAME, Qmmp::UNKNOWN },
+        { PlayListModel::PATH_AND_FILENAME, Qmmp::UNKNOWN },
+        { PlayListModel::DATE, Qmmp::YEAR },
+        { PlayListModel::TRACK, Qmmp::TRACK },
+        { PlayListModel::FILE_CREATION_DATE, Qmmp::UNKNOWN },
+        { PlayListModel::FILE_MODIFICATION_DATE, Qmmp::UNKNOWN }
+    };
 }
 
 PlayListTask::~PlayListTask()
@@ -335,10 +330,9 @@ void PlayListTask::run()
         if(m_align_groups)
         {
             QList<GroupdField *> groups;
-            bool found = false;
             for(int i = 0; i < m_fields.count(); ++i)
             {
-                found = false;
+                bool found = false;
                 for(int j = groups.count() - 1; j >= 0; j--)
                 {
                     if(groups[j]->groupName == m_fields[i]->groupName)
@@ -453,11 +447,11 @@ void PlayListTask::run()
         QList<int> indexes;
         for(int i = 0; i < l.count(); ++i)
         {
-            QFileInfo f = l[i];
-            if(urls.contains(f.canonicalFilePath()))
+            QFileInfo info = l[i];
+            if(urls.contains(info.canonicalFilePath()))
                 indexes.append(i);
             else
-                urls.append(f.canonicalFilePath());
+                urls.append(info.canonicalFilePath());
         }
         //remove existing URLs
         for(int i = indexes.count() - 1; i >= 0; i--)
@@ -466,10 +460,10 @@ void PlayListTask::run()
         //create new playlist tracks
         QStringList ignoredFiles;
         TrackInfo::Parts parts = QmmpUiSettings::instance()->useMetaData() ? TrackInfo::AllParts : TrackInfo::Parts();
-        for(const QFileInfo &f : qAsConst(l))
+        for(const QFileInfo &info : qAsConst(l))
         {
             QStringList ignored;
-            for(TrackInfo *info : mm->createPlayList(f.canonicalFilePath(), parts, &ignored))
+            for(TrackInfo *info : mm->createPlayList(info.canonicalFilePath(), parts, &ignored))
             {
                 m_new_tracks << new PlayListTrack(info);
             }
@@ -522,12 +516,10 @@ QList<PlayListTrack *> PlayListTask::takeResults(PlayListTrack **current_track)
     }
     else if(m_task == REMOVE_INVALID || m_task == REMOVE_DUPLICATES || m_task == REFRESH)
     {
-        int index = 0;
-        PlayListTrack *t = nullptr;
         for (int i = m_indexes.count() - 1; i >= 0; i--)
         {
-            index = m_indexes.at(i);
-            t = m_tracks.takeAt(index);
+            int index = m_indexes.at(i);
+            PlayListTrack *t = m_tracks.takeAt(index);
             if(t == m_current_track)
             {
                 if(m_tracks.isEmpty())
diff --git a/src/qmmpui/playlisttask_p.h b/src/qmmpui/playlisttask_p.h
index 1b2aaca8d..1ce3f9f32 100644
--- a/src/qmmpui/playlisttask_p.h
+++ b/src/qmmpui/playlisttask_p.h
@@ -76,11 +76,11 @@ private:
     QList<int> m_indexes;
     QList <PlayListTrack *> m_new_tracks;
     PlayListTrack *m_current_track;
-    int m_sort_mode;
-    TaskType m_task;
-    bool m_reverted;
-    bool m_align_groups;
-    int m_column;
+    int m_sort_mode = PlayListModel::TITLE;
+    TaskType m_task = EMPTY;
+    bool m_reverted = true;
+    bool m_align_groups = false;
+    int m_column = 0;
     QHash<int, Qmmp::MetaData> m_sort_keys;
 
 };
diff --git a/src/qmmpui/playlisttrack.cpp b/src/qmmpui/playlisttrack.cpp
index d44a3cd7b..0f89314e6 100644
--- a/src/qmmpui/playlisttrack.cpp
+++ b/src/qmmpui/playlisttrack.cpp
@@ -26,21 +26,15 @@
 
 PlayListTrack::PlayListTrack() : TrackInfo(), PlayListItem()
 {
-    m_track_index = -1;
     m_settings = QmmpUiSettings::instance();
     m_helper = MetaDataHelper::instance();
-    m_refCount = 0;
-    m_sheduledForDeletion = false;
 }
 
 PlayListTrack::PlayListTrack(const PlayListTrack &other) : TrackInfo(other),
     PlayListItem()
 {
-    m_track_index = -1;
     m_settings = QmmpUiSettings::instance();
     m_helper = MetaDataHelper::instance();
-    m_refCount = 0;
-    m_sheduledForDeletion = false;
 
     m_formattedTitles = other.m_formattedTitles;
     m_group = other.m_group;
@@ -54,11 +48,8 @@ PlayListTrack::PlayListTrack(const PlayListTrack &other) : TrackInfo(other),
 PlayListTrack::PlayListTrack(TrackInfo *info) : TrackInfo(*info),
     PlayListItem()
 {
-    m_track_index = -1;
     m_settings = QmmpUiSettings::instance();
     m_helper = MetaDataHelper::instance();
-    m_refCount = 0;
-    m_sheduledForDeletion = false;
 }
 
 PlayListTrack::~PlayListTrack()
diff --git a/src/qmmpui/playlisttrack.h b/src/qmmpui/playlisttrack.h
index 1229d063a..2d878e176 100644
--- a/src/qmmpui/playlisttrack.h
+++ b/src/qmmpui/playlisttrack.h
@@ -43,7 +43,7 @@ public:
     /*!
      * Constructs a new PlayListTrack that is a copy of the given track \b other
      */
-    PlayListTrack(const PlayListTrack &other);
+    explicit PlayListTrack(const PlayListTrack &other);
     /*!
      * Constructs plalist item with given metadata.
      * @param info Media file information.
@@ -129,9 +129,9 @@ private:
     QStringList m_titleFormats;
     QString m_groupFormat;
     QmmpUiSettings *m_settings;
-    int m_refCount;
-    int m_track_index;
-    bool m_sheduledForDeletion;
+    int m_refCount = 0;
+    int m_track_index = -1;
+    bool m_sheduledForDeletion = false;
     MetaDataHelper *m_helper;
 };
 
diff --git a/src/qmmpui/playstate_p.h b/src/qmmpui/playstate_p.h
index 22e619875..221ea9cde 100644
--- a/src/qmmpui/playstate_p.h
+++ b/src/qmmpui/playstate_p.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2007-2013 by Ilya Kotov                                 *
+ *   Copyright (C) 2007-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -62,7 +62,7 @@ public:
     {
         ;
     }
-    PlayState(PlayListModel* model);
+    explicit PlayState(PlayListModel* model);
 
 protected:
     /// Data model
@@ -80,7 +80,7 @@ public:
     virtual bool next() override;
     virtual bool previous() override;
     virtual int nextIndex() override;
-    NormalPlayState(PlayListModel* model);
+    explicit NormalPlayState(PlayListModel* model);
 };
 
 /*! @internal
@@ -94,12 +94,12 @@ public:
     virtual bool previous() override;
     virtual int nextIndex() override;
     virtual void prepare() override;
-    ShufflePlayState(PlayListModel* model);
+    explicit ShufflePlayState(PlayListModel* model);
     virtual void resetState() override;
 private:
 
     /// Current shuffled index.
-    int m_shuffled_current;
+    int m_shuffled_current = 0;
 
     /// List of indexes used for shuffled playing.
     QList<int> m_shuffled_indexes;
diff --git a/src/qmmpui/qmmpuiplugincache.cpp b/src/qmmpui/qmmpuiplugincache.cpp
index c90b49386..011cbfff0 100644
--- a/src/qmmpui/qmmpuiplugincache.cpp
+++ b/src/qmmpui/qmmpuiplugincache.cpp
@@ -32,12 +32,6 @@
 
 QmmpUiPluginCache::QmmpUiPluginCache(const QString &file, QSettings *settings)
 {
-    m_error = false;
-    m_instance = nullptr;
-    m_generalFactory = nullptr;
-    m_uiFactory = nullptr;
-    m_fileDialogFactory = nullptr;
-    m_priority = 0;
     bool update = false;
     QFileInfo info(file);
     m_path = info.QFileInfo::canonicalFilePath();
@@ -102,13 +96,8 @@ QmmpUiPluginCache::QmmpUiPluginCache(const QString &file, QSettings *settings)
 }
 
 QmmpUiPluginCache::QmmpUiPluginCache(QObject *instance)
-{
-    m_error = false;
+{   
     m_instance = instance;
-    m_generalFactory = nullptr;
-    m_uiFactory = nullptr;
-    m_fileDialogFactory = nullptr;
-    m_priority = 0;
 
     if(GeneralFactory *factory = generalFactory())
     {
diff --git a/src/qmmpui/qmmpuiplugincache_p.h b/src/qmmpui/qmmpuiplugincache_p.h
index 4454b3045..db5c149d6 100644
--- a/src/qmmpui/qmmpuiplugincache_p.h
+++ b/src/qmmpui/qmmpuiplugincache_p.h
@@ -36,7 +36,7 @@ class QmmpUiPluginCache
 {
 public:
     QmmpUiPluginCache(const QString &file, QSettings *settings);
-    QmmpUiPluginCache(QObject *instance);
+    explicit QmmpUiPluginCache(QObject *instance);
 
     const QString shortName() const;
     const QString file() const;
@@ -54,12 +54,12 @@ private:
     void loadTranslation(const QString &translation);
     QString m_path;
     QString m_shortName;
-    bool m_error;
-    QObject *m_instance;
-    GeneralFactory *m_generalFactory;
-    UiFactory *m_uiFactory;
-    FileDialogFactory *m_fileDialogFactory;
-    int m_priority;
+    bool m_error = false;
+    QObject *m_instance = nullptr;
+    GeneralFactory *m_generalFactory = nullptr;
+    UiFactory *m_uiFactory = nullptr;
+    FileDialogFactory *m_fileDialogFactory = nullptr;
+    int m_priority = 0;
 };
 
 #endif // QMMPUIPLUGINCACHE_P_H
diff --git a/src/qmmpui/tageditor.cpp b/src/qmmpui/tageditor.cpp
index ff01c5fb3..96dc5d10a 100644
--- a/src/qmmpui/tageditor.cpp
+++ b/src/qmmpui/tageditor.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2009-2016 by Ilya Kotov                                 *
+ *   Copyright (C) 2009-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -26,7 +26,6 @@ TagEditor::TagEditor(TagModel *tagModel, QWidget *parent) : QWidget(parent), m_u
 {
     m_ui->setupUi(this);
     m_tagModel = tagModel;
-    m_discs = -1;
     //check available keys
     m_ui->titleLineEdit->setEnabled(m_tagModel->keys().contains(Qmmp::TITLE));
     m_ui->artistLineEdit->setEnabled(m_tagModel->keys().contains(Qmmp::ARTIST));
diff --git a/src/qmmpui/tageditor_p.h b/src/qmmpui/tageditor_p.h
index 1e332086c..dc439f0f7 100644
--- a/src/qmmpui/tageditor_p.h
+++ b/src/qmmpui/tageditor_p.h
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2009-2016 by Ilya Kotov                                 *
+ *   Copyright (C) 2009-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -36,7 +36,7 @@ class TagEditor : public QWidget
 {
 Q_OBJECT
 public:
-    TagEditor(TagModel *tagModel, QWidget *parent = nullptr);
+    explicit TagEditor(TagModel *tagModel, QWidget *parent = nullptr);
     ~TagEditor();
 
     void save();
@@ -45,7 +45,7 @@ private:
     void readTag();
     Ui::TagEditor *m_ui;
     TagModel *m_tagModel;
-    int m_discs; //Number of discs
+    int m_discs = -1; //Number of discs
 
 };
 
diff --git a/src/qmmpui/tagupdater.cpp b/src/qmmpui/tagupdater.cpp
index 1feb7cb21..e0c3ed4e6 100644
--- a/src/qmmpui/tagupdater.cpp
+++ b/src/qmmpui/tagupdater.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2013 by Ilya Kotov                                      *
+ *   Copyright (C) 2013-2020 by Ilya Kotov                                 *
  *   forkotov02@ya.ru                                                      *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -20,9 +20,10 @@
 
 #include "tagupdater_p.h"
 
-TagUpdater::TagUpdater(QObject* o, QList<PlayListTrack *> tracks) : m_observable(o)
+TagUpdater::TagUpdater(QObject* o, QList<PlayListTrack *> tracks) :
+    m_observable(o),
+    m_tracks(tracks)
 {
-    m_tracks = tracks;
     for(PlayListTrack *t : qAsConst(m_tracks))
         t->beginUsage();
     connect(m_observable, SIGNAL(destroyed(QObject *)),SLOT(updateTags()));
diff --git a/src/qmmpui/uihelper.cpp b/src/qmmpui/uihelper.cpp
index d2ada8e9b..6e800b831 100644
--- a/src/qmmpui/uihelper.cpp
+++ b/src/qmmpui/uihelper.cpp
@@ -26,6 +26,7 @@
 #include <QApplication>
 #include <QMessageBox>
 #include <QFileInfo>
+#include <algorithm>
 #include <qmmp/soundcore.h>
 #include <qmmp/metadatamanager.h>
 #include "filedialog.h"
@@ -46,7 +47,6 @@ UiHelper::UiHelper(QObject *parent)
         : QObject(parent)
 {
     m_instance = this;
-    m_jumpDialog = nullptr;
     General::create(parent);
     QSettings settings(Qmmp::configFile(), QSettings::IniFormat);
     m_lastDir = settings.value("General/last_dir", QDir::homePath()).toString(); //last directory
@@ -60,12 +60,9 @@ UiHelper::~UiHelper()
 
 bool UiHelper::visibilityControl()
 {
-    for(const GeneralFactory *factory : General::enabledFactories())
-    {
-        if (factory->properties().visibilityControl)
-            return true;
-    }
-    return false;
+    const QList<GeneralFactory *> factories = General::enabledFactories();
+    return std::any_of(factories.cbegin(), factories.cend(),
+                       [](GeneralFactory *factory){ return factory->properties().visibilityControl; });
 }
 
 void UiHelper::addAction(QAction *action, MenuType type)
@@ -292,7 +289,7 @@ UiHelper* UiHelper::instance()
 
 void UiHelper::removeAction(QObject *action)
 {
-    removeAction((QAction *) action);
+    removeAction(qobject_cast<QAction *>(action));
 }
 
 void UiHelper::addSelectedFiles(const QStringList &files, bool play)
diff --git a/src/qmmpui/uiloader.cpp b/src/qmmpui/uiloader.cpp
index 8a3ef0c7a..4d64c23bf 100644
--- a/src/qmmpui/uiloader.cpp
+++ b/src/qmmpui/uiloader.cpp
@@ -20,6 +20,7 @@
 
 #include <QDir>
 #include <qmmp/qmmp.h>
+#include <algorithm>
 #include "qmmpuiplugincache_p.h"
 #include "uiloader.h"
 
@@ -74,12 +75,9 @@ QStringList UiLoader::names()
 QString UiLoader::file(UiFactory *factory)
 {
     loadPlugins();
-    for(const QmmpUiPluginCache *item : qAsConst(*m_cache))
-    {
-        if(item->shortName() == factory->properties().shortName)
-            return item->file();
-    }
-    return QString();
+    auto it = std::find_if(m_cache->cbegin(), m_cache->cend(),
+                           [factory](QmmpUiPluginCache *item) { return item->shortName() == factory->properties().shortName; } );
+    return it == m_cache->cend() ? QString() : (*it)->file();
 }
 
 void UiLoader::select(UiFactory* factory)
@@ -90,14 +88,10 @@ void UiLoader::select(UiFactory* factory)
 void UiLoader::select(const QString &name)
 {
     loadPlugins();
-    for(const QmmpUiPluginCache *item : qAsConst(*m_cache))
+    if(std::any_of(m_cache->cbegin(), m_cache->cend(), [name](QmmpUiPluginCache *item) { return item->shortName() == name; } ))
     {
-        if(item->shortName() == name)
-        {
-            QSettings settings (Qmmp::configFile(), QSettings::IniFormat);
-            settings.setValue ("Ui/current_plugin", name);
-            break;
-        }
+        QSettings settings (Qmmp::configFile(), QSettings::IniFormat);
+        settings.setValue ("Ui/current_plugin", name);
     }
 }
 
diff --git a/src/qmmpui/winfileassoc.cpp b/src/qmmpui/winfileassoc.cpp
index 99e82e7e8..1d99ea933 100644
--- a/src/qmmpui/winfileassoc.cpp
+++ b/src/qmmpui/winfileassoc.cpp
@@ -55,10 +55,8 @@
 #define SHCNE_ASSOCHANGED __MSABI_LONG(0x08000000)
 #endif
 
-WinFileAssoc::WinFileAssoc(const QString AppName)
-{
-    m_AppName = AppName;
-}
+WinFileAssoc::WinFileAssoc(const QString AppName) : m_AppName(AppName)
+{}
 
 // Associates all extensions in the fileExtensions list with current app.
 // Returns number of extensions processed successfully.
diff --git a/src/qmmpui/winfileassocpage.cpp b/src/qmmpui/winfileassocpage.cpp
index 9b1fef989..4f0484b0e 100644
--- a/src/qmmpui/winfileassocpage.cpp
+++ b/src/qmmpui/winfileassocpage.cpp
@@ -2,7 +2,7 @@
  * Based on smplayer - GUI front-end for mplayer                           *
  *                                                                         *
  * Copyright (C) 2006-2014 Ricardo Villalba <rvm@users.sourceforge.net>    *
- * Copyright (C) 2014 Ilya Kotov forkotov02@ya.ru                          *
+ * Copyright (C) 2014-2020 Ilya Kotov forkotov02@ya.ru                     *
  *                                                                         *
  *   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  *
@@ -98,7 +98,7 @@ void WinFileAssocPage::loadAssociations()
     }
 }
 
-int WinFileAssocPage::ProcessAssociations(QStringList& current)
+int WinFileAssocPage::ProcessAssociations(const QStringList &current)
 {
     WinFileAssoc RegAssoc;
     return RegAssoc.CreateFileAssociations(current);
diff --git a/src/qmmpui/winfileassocpage_p.h b/src/qmmpui/winfileassocpage_p.h
index b805cf1ab..3175f13ed 100644
--- a/src/qmmpui/winfileassocpage_p.h
+++ b/src/qmmpui/winfileassocpage_p.h
@@ -48,7 +48,7 @@ private slots:
 private:
     void loadAssociations();
     void saveAssociations();
-    int ProcessAssociations(QStringList& current);
+    int ProcessAssociations(const QStringList &current);
     void createHelp();
     QStringList m_extensions;
     QStringList m_regExtensions;