From 8e0d792bf00a721769518a0a7372b44a847f9ec7 Mon Sep 17 00:00:00 2001
From: Jonas Kvinge <jonas@jkvinge.net>
Date: Sat, 8 Feb 2020 03:40:30 +0100
Subject: [PATCH] Reduce includes

---
 .../singleapplication/singleapplication.cpp   |  5 +++
 .../singleapplication/singleapplication.h     |  3 +-
 .../singleapplication/singleapplication_p.cpp |  4 ++-
 .../singleapplication/singleapplication_p.h   |  8 +++--
 .../singlecoreapplication.cpp                 |  5 +++
 .../singleapplication/singlecoreapplication.h |  3 +-
 .../singlecoreapplication_p.cpp               |  4 ++-
 .../singlecoreapplication_p.h                 |  8 +++--
 ext/gstmoodbar/gstfastspectrum.cpp            |  6 ++--
 ext/gstmoodbar/gstmoodbarplugin.cpp           |  1 +
 ext/libstrawberry-common/core/closure.cpp     |  1 -
 .../core/messagehandler.h                     |  3 +-
 ext/libstrawberry-common/core/workerpool.h    |  6 ++--
 ext/libstrawberry-tagreader/fmpsparser.cpp    |  1 +
 ext/libstrawberry-tagreader/fmpsparser.h      |  3 +-
 ext/libstrawberry-tagreader/tagreader.cpp     |  4 ++-
 ext/libstrawberry-tagreader/tagreader.h       |  3 +-
 ext/strawberry-tagreader/tagreaderworker.h    |  5 ++-
 src/analyzer/analyzerbase.h                   |  1 -
 src/analyzer/analyzercontainer.cpp            |  1 +
 src/analyzer/analyzercontainer.h              |  3 +-
 src/analyzer/blockanalyzer.cpp                |  1 -
 src/analyzer/blockanalyzer.h                  |  5 +--
 src/analyzer/boomanalyzer.cpp                 |  7 +++-
 src/analyzer/boomanalyzer.h                   |  3 +-
 src/analyzer/rainbowanalyzer.cpp              |  8 +++--
 src/analyzer/rainbowanalyzer.h                |  8 ++++-
 src/collection/collection.cpp                 |  5 +--
 src/collection/collection.h                   |  4 ++-
 src/collection/collectionbackend.cpp          | 13 +++-----
 src/collection/collectionbackend.h            |  3 --
 src/collection/collectiondirectorymodel.cpp   |  2 --
 src/collection/collectionfilterwidget.cpp     |  1 +
 src/collection/collectionfilterwidget.h       |  2 --
 src/collection/collectionitemdelegate.cpp     |  6 ++--
 src/collection/collectionitemdelegate.h       |  7 ++--
 src/collection/collectionmodel.cpp            | 12 ++++---
 src/collection/collectionmodel.h              | 12 +++----
 src/collection/collectionplaylistitem.cpp     |  1 -
 src/collection/collectionplaylistitem.h       |  2 --
 src/collection/collectionquery.cpp            |  1 -
 src/collection/collectionquery.h              |  2 --
 src/collection/collectionview.cpp             | 32 ++++++-------------
 src/collection/collectionview.h               | 12 ++-----
 src/collection/collectionwatcher.cpp          |  2 --
 src/collection/collectionwatcher.h            |  6 ++--
 src/collection/groupbydialog.cpp              |  3 +-
 src/collection/groupbydialog.h                |  3 +-
 src/collection/savedgroupingmanager.h         |  5 +--
 src/context/contextalbumsmodel.cpp            |  5 ---
 src/context/contextalbumsmodel.h              |  8 ++---
 src/context/contextalbumsview.cpp             | 29 +++--------------
 src/context/contextalbumsview.h               | 21 ++++++------
 src/context/contextview.cpp                   | 17 +++++-----
 src/context/contextview.h                     | 17 ++++++----
 src/core/application.cpp                      |  2 +-
 src/core/application.h                        |  3 +-
 src/core/commandlineoptions.cpp               |  1 +
 src/core/database.cpp                         |  3 +-
 src/core/database.h                           |  2 --
 src/core/deletefiles.h                        |  3 +-
 src/core/iconloader.h                         |  1 -
 src/core/mainwindow.cpp                       | 21 +++++++++---
 src/core/mainwindow.h                         |  5 +--
 src/core/mergedproxymodel.cpp                 |  3 ++
 src/core/mergedproxymodel.h                   |  4 +--
 src/core/metatypes.cpp                        |  2 +-
 src/core/multisortfilterproxy.cpp             |  2 ++
 src/core/multisortfilterproxy.h               |  4 +--
 src/core/musicstorage.h                       |  2 ++
 src/core/network.cpp                          |  7 ++--
 src/core/network.h                            |  8 ++---
 src/core/networkproxyfactory.h                |  1 -
 src/core/networktimeouts.h                    |  1 -
 src/core/player.h                             |  6 ++--
 src/core/qtfslistener.cpp                     |  2 --
 src/core/qtsystemtrayicon.h                   |  4 +--
 src/core/scangiomodulepath.cpp                |  3 +-
 src/core/scopedtransaction.h                  |  2 +-
 src/core/song.cpp                             |  2 --
 src/core/song.h                               |  5 +--
 src/core/songloader.cpp                       |  1 -
 src/core/songloader.h                         |  2 +-
 src/core/standarditemiconloader.cpp           |  2 +-
 src/core/standarditemiconloader.h             |  6 ++--
 src/core/stylesheetloader.cpp                 |  3 ++
 src/core/stylesheetloader.h                   |  7 ++--
 src/core/systemtrayicon.h                     |  5 +--
 src/core/thread.h                             |  3 +-
 src/core/translations.h                       |  3 +-
 src/core/utilities.cpp                        | 15 +++++----
 src/core/utilities.h                          |  7 ++--
 src/engine/devicefinders.cpp                  |  1 -
 src/engine/enginetype.cpp                     |  1 -
 src/equalizer/equalizer.cpp                   |  2 +-
 src/equalizer/equalizer.h                     |  2 +-
 src/equalizer/equalizerslider.cpp             |  2 ++
 src/playlist/playlistbackend.h                |  1 -
 98 files changed, 260 insertions(+), 245 deletions(-)

diff --git a/3rdparty/singleapplication/singleapplication.cpp b/3rdparty/singleapplication/singleapplication.cpp
index 63dcaa8ea..ebea0aeee 100644
--- a/3rdparty/singleapplication/singleapplication.cpp
+++ b/3rdparty/singleapplication/singleapplication.cpp
@@ -31,13 +31,18 @@
 //
 //
 
+#include <stdlib.h>
+#include <limits>
+
 #include <QtGlobal>
 #include <QCoreApplication>
 #include <QThread>
 #include <QSharedMemory>
+#include <QLocalSocket>
 #include <QByteArray>
 #include <QDateTime>
 #include <QElapsedTimer>
+#include <QtDebug>
 
 #include "singleapplication.h"
 #include "singleapplication_p.h"
diff --git a/3rdparty/singleapplication/singleapplication.h b/3rdparty/singleapplication/singleapplication.h
index b4bac1f33..69d250ef1 100644
--- a/3rdparty/singleapplication/singleapplication.h
+++ b/3rdparty/singleapplication/singleapplication.h
@@ -36,7 +36,8 @@
 
 #include <QtGlobal>
 #include <QApplication>
-#include <QLocalSocket>
+#include <QFlags>
+#include <QByteArray>
 
 class SingleApplicationPrivate;
 
diff --git a/3rdparty/singleapplication/singleapplication_p.cpp b/3rdparty/singleapplication/singleapplication_p.cpp
index 427dde26f..a9142af9c 100644
--- a/3rdparty/singleapplication/singleapplication_p.cpp
+++ b/3rdparty/singleapplication/singleapplication_p.cpp
@@ -44,12 +44,14 @@
 #  include <pwd.h>
 #endif
 
-#include <QDir>
+#include <QIODevice>
+#include <QSharedMemory>
 #include <QByteArray>
 #include <QDataStream>
 #include <QCryptographicHash>
 #include <QLocalServer>
 #include <QLocalSocket>
+#include <QDir>
 
 #include "singleapplication.h"
 #include "singleapplication_p.h"
diff --git a/3rdparty/singleapplication/singleapplication_p.h b/3rdparty/singleapplication/singleapplication_p.h
index 7e752b12f..650c51c59 100644
--- a/3rdparty/singleapplication/singleapplication_p.h
+++ b/3rdparty/singleapplication/singleapplication_p.h
@@ -35,13 +35,15 @@
 #define SINGLEAPPLICATION_P_H
 
 #include <QtGlobal>
-#include <QLocalSocket>
-#include <QLocalServer>
-#include <QSharedMemory>
+#include <QObject>
 #include <QMap>
 
 #include "singleapplication.h"
 
+class QLocalServer;
+class QLocalSocket;
+class QSharedMemory;
+
 struct InstancesInfo {
   bool primary;
   quint32 secondary;
diff --git a/3rdparty/singleapplication/singlecoreapplication.cpp b/3rdparty/singleapplication/singlecoreapplication.cpp
index 54ed4f1a0..0d975e138 100644
--- a/3rdparty/singleapplication/singlecoreapplication.cpp
+++ b/3rdparty/singleapplication/singlecoreapplication.cpp
@@ -31,13 +31,18 @@
 //
 //
 
+#include <stdlib.h>
+#include <limits>
+
 #include <QtGlobal>
 #include <QCoreApplication>
 #include <QThread>
 #include <QSharedMemory>
+#include <QLocalSocket>
 #include <QByteArray>
 #include <QDateTime>
 #include <QElapsedTimer>
+#include <QtDebug>
 
 #include "singlecoreapplication.h"
 #include "singlecoreapplication_p.h"
diff --git a/3rdparty/singleapplication/singlecoreapplication.h b/3rdparty/singleapplication/singlecoreapplication.h
index 18a95ad5d..45877ca6e 100644
--- a/3rdparty/singleapplication/singlecoreapplication.h
+++ b/3rdparty/singleapplication/singlecoreapplication.h
@@ -36,7 +36,8 @@
 
 #include <QtGlobal>
 #include <QCoreApplication>
-#include <QLocalSocket>
+#include <QFlags>
+#include <QByteArray>
 
 class SingleCoreApplicationPrivate;
 
diff --git a/3rdparty/singleapplication/singlecoreapplication_p.cpp b/3rdparty/singleapplication/singlecoreapplication_p.cpp
index a6f787df1..e58c8b4f6 100644
--- a/3rdparty/singleapplication/singlecoreapplication_p.cpp
+++ b/3rdparty/singleapplication/singlecoreapplication_p.cpp
@@ -44,12 +44,14 @@
 #  include <pwd.h>
 #endif
 
-#include <QDir>
+#include <QIODevice>
+#include <QSharedMemory>
 #include <QByteArray>
 #include <QDataStream>
 #include <QCryptographicHash>
 #include <QLocalServer>
 #include <QLocalSocket>
+#include <QDir>
 
 #include "singlecoreapplication.h"
 #include "singlecoreapplication_p.h"
diff --git a/3rdparty/singleapplication/singlecoreapplication_p.h b/3rdparty/singleapplication/singlecoreapplication_p.h
index 54dcab392..d8d7e743a 100644
--- a/3rdparty/singleapplication/singlecoreapplication_p.h
+++ b/3rdparty/singleapplication/singlecoreapplication_p.h
@@ -35,13 +35,15 @@
 #define SINGLECOREAPPLICATION_P_H
 
 #include <QtGlobal>
-#include <QLocalSocket>
-#include <QLocalServer>
-#include <QSharedMemory>
+#include <QObject>
 #include <QMap>
 
 #include "singlecoreapplication.h"
 
+class QLocalServer;
+class QLocalSocket;
+class QSharedMemory;
+
 struct InstancesInfo {
   bool primary;
   quint32 secondary;
diff --git a/ext/gstmoodbar/gstfastspectrum.cpp b/ext/gstmoodbar/gstfastspectrum.cpp
index e158becf3..356576cf1 100644
--- a/ext/gstmoodbar/gstfastspectrum.cpp
+++ b/ext/gstmoodbar/gstfastspectrum.cpp
@@ -19,14 +19,16 @@
  * Boston, MA 02110-1301, USA.
  */
 
+#include <QtGlobal>
+
 #include <cstring>
-#include <cmath>
+
+#include <glib.h>
 
 #include <gst/gst.h>
 #include <gst/audio/gstaudiofilter.h>
 
 #include <QMutex>
-#include <QMutexLocker>
 
 #include "gstfastspectrum.h"
 
diff --git a/ext/gstmoodbar/gstmoodbarplugin.cpp b/ext/gstmoodbar/gstmoodbarplugin.cpp
index 13dd00ff0..9d47e4df5 100644
--- a/ext/gstmoodbar/gstmoodbarplugin.cpp
+++ b/ext/gstmoodbar/gstmoodbarplugin.cpp
@@ -15,6 +15,7 @@
    along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <glib.h>
 #include <gst/gst.h>
 
 #include "gstfastspectrum.h"
diff --git a/ext/libstrawberry-common/core/closure.cpp b/ext/libstrawberry-common/core/closure.cpp
index d1d157d46..17db12f97 100644
--- a/ext/libstrawberry-common/core/closure.cpp
+++ b/ext/libstrawberry-common/core/closure.cpp
@@ -22,7 +22,6 @@
 
 #include "closure.h"
 
-#include "core/logging.h"
 #include "core/timeconstants.h"
 
 namespace _detail {
diff --git a/ext/libstrawberry-common/core/messagehandler.h b/ext/libstrawberry-common/core/messagehandler.h
index f99aba16a..04896d0ac 100644
--- a/ext/libstrawberry-common/core/messagehandler.h
+++ b/ext/libstrawberry-common/core/messagehandler.h
@@ -23,7 +23,6 @@
 #include <QtGlobal>
 #include <QObject>
 #include <QThread>
-#include <QIODevice>
 #include <QBuffer>
 #include <QByteArray>
 #include <QMap>
@@ -33,6 +32,8 @@
 
 #include "core/messagereply.h"
 
+class QIODevice;
+
 #define QStringFromStdString(x) QString::fromUtf8(x.data(), x.size())
 #define DataCommaSizeFromQString(x) x.toUtf8().constData(), x.toUtf8().length()
 
diff --git a/ext/libstrawberry-common/core/workerpool.h b/ext/libstrawberry-common/core/workerpool.h
index 08b8baf40..b6a61c1a6 100644
--- a/ext/libstrawberry-common/core/workerpool.h
+++ b/ext/libstrawberry-common/core/workerpool.h
@@ -25,12 +25,11 @@
 #include <QCoreApplication>
 #include <QThread>
 #include <QMutex>
+#include <QLocalServer>
 #include <QProcess>
-#include <QQueue>
 #include <QFile>
 #include <QList>
-#include <QLocalServer>
-#include <QLocalSocket>
+#include <QQueue>
 #include <QString>
 #include <QStringList>
 #include <QAtomicInt>
@@ -39,7 +38,6 @@
 
 class QLocalSocket;
 
-
 // Base class containing signals and slots - required because moc doesn't do templated objects.
 class _WorkerPoolBase : public QObject {
   Q_OBJECT
diff --git a/ext/libstrawberry-tagreader/fmpsparser.cpp b/ext/libstrawberry-tagreader/fmpsparser.cpp
index 600f41944..556e74f4e 100644
--- a/ext/libstrawberry-tagreader/fmpsparser.cpp
+++ b/ext/libstrawberry-tagreader/fmpsparser.cpp
@@ -22,6 +22,7 @@
 #include <QList>
 #include <QVariant>
 #include <QString>
+#include <QChar>
 
 #include "fmpsparser.h"
 
diff --git a/ext/libstrawberry-tagreader/fmpsparser.h b/ext/libstrawberry-tagreader/fmpsparser.h
index 81c7f7c33..1090305e9 100644
--- a/ext/libstrawberry-tagreader/fmpsparser.h
+++ b/ext/libstrawberry-tagreader/fmpsparser.h
@@ -22,10 +22,11 @@
 
 #include <QList>
 #include <QMetaType>
-#include <QVariant>
 #include <QString>
 #include <QRegExp>
 
+class QVariant;
+
 class FMPSParser {
 public:
   FMPSParser();
diff --git a/ext/libstrawberry-tagreader/tagreader.cpp b/ext/libstrawberry-tagreader/tagreader.cpp
index 6d10521f5..760d8e436 100644
--- a/ext/libstrawberry-tagreader/tagreader.cpp
+++ b/ext/libstrawberry-tagreader/tagreader.cpp
@@ -23,7 +23,6 @@
 #include <memory>
 #include <list>
 #include <map>
-#include <utility>
 #include <sys/stat.h>
 
 #include <taglib/taglib.h>
@@ -42,6 +41,8 @@
 #include <taglib/commentsframe.h>
 #include <taglib/tag.h>
 #include <taglib/apetag.h>
+#include <taglib/apeitem.h>
+#include <taglib/apeproperties.h>
 #include <taglib/id3v2tag.h>
 #include <taglib/id3v2frame.h>
 #include <taglib/flacfile.h>
@@ -52,6 +53,7 @@
 #include <taglib/speexfile.h>
 #include <taglib/wavfile.h>
 #include <taglib/wavpackfile.h>
+#include <taglib/wavpackproperties.h>
 #include <taglib/aifffile.h>
 #include <taglib/asffile.h>
 #include <taglib/asftag.h>
diff --git a/ext/libstrawberry-tagreader/tagreader.h b/ext/libstrawberry-tagreader/tagreader.h
index 5c108c1ea..f7ba99368 100644
--- a/ext/libstrawberry-tagreader/tagreader.h
+++ b/ext/libstrawberry-tagreader/tagreader.h
@@ -25,7 +25,6 @@
 
 #include <QByteArray>
 #include <QString>
-#include <QTextCodec>
 
 #include <taglib/xiphcomment.h>
 #include <taglib/apetag.h>
@@ -33,6 +32,8 @@
 
 #include "tagreadermessages.pb.h"
 
+class QTextCodec;
+
 #ifndef USE_SYSTEM_TAGLIB
 namespace Strawberry_TagLib {
 #endif
diff --git a/ext/strawberry-tagreader/tagreaderworker.h b/ext/strawberry-tagreader/tagreaderworker.h
index 8ced818a7..80c677edb 100644
--- a/ext/strawberry-tagreader/tagreaderworker.h
+++ b/ext/strawberry-tagreader/tagreaderworker.h
@@ -20,15 +20,14 @@
 
 #include "config.h"
 
-#include <stddef.h>
-
 #include <QObject>
-#include <QIODevice>
 
 #include "core/messagehandler.h"
 #include "tagreader.h"
 #include "tagreadermessages.pb.h"
 
+class QIODevice;
+
 class TagReaderWorker : public AbstractMessageHandler<pb::tagreader::Message> {
 public:
   TagReaderWorker(QIODevice *socket, QObject *parent = nullptr);
diff --git a/src/analyzer/analyzerbase.h b/src/analyzer/analyzerbase.h
index e751547ef..6127a905e 100644
--- a/src/analyzer/analyzerbase.h
+++ b/src/analyzer/analyzerbase.h
@@ -37,7 +37,6 @@
 #include <QBasicTimer>
 #include <QString>
 #include <QPainter>
-#include <QtEvents>
 
 #include "analyzer/fht.h"
 #include "engine/engine_fwd.h"
diff --git a/src/analyzer/analyzercontainer.cpp b/src/analyzer/analyzercontainer.cpp
index 1fbc47af3..55057463d 100644
--- a/src/analyzer/analyzercontainer.cpp
+++ b/src/analyzer/analyzercontainer.cpp
@@ -41,6 +41,7 @@
 #include "rainbowanalyzer.h"
 
 #include "core/logging.h"
+#include "engine/enginebase.h"
 #include "engine/enginetype.h"
 
 const char *AnalyzerContainer::kSettingsGroup = "Analyzer";
diff --git a/src/analyzer/analyzercontainer.h b/src/analyzer/analyzercontainer.h
index 7af78f655..e38441055 100644
--- a/src/analyzer/analyzercontainer.h
+++ b/src/analyzer/analyzercontainer.h
@@ -22,18 +22,17 @@
 
 #include "config.h"
 
-
 #include <QWidget>
 #include <QList>
 #include <QString>
 #include <QPoint>
 #include <QMenu>
 #include <QAction>
-#include <QActionGroup>
 
 #include "engine/engine_fwd.h"
 
 class QTimer;
+class QActionGroup;
 class QMouseEvent;
 class QWheelEvent;
 
diff --git a/src/analyzer/blockanalyzer.cpp b/src/analyzer/blockanalyzer.cpp
index 35a517d45..e9c7262fb 100644
--- a/src/analyzer/blockanalyzer.cpp
+++ b/src/analyzer/blockanalyzer.cpp
@@ -31,7 +31,6 @@
 #include <QPainter>
 #include <QPalette>
 #include <QColor>
-#include <QtEvents>
 
 #include "analyzerbase.h"
 #include "fht.h"
diff --git a/src/analyzer/blockanalyzer.h b/src/analyzer/blockanalyzer.h
index 778fdc002..e81c8a235 100644
--- a/src/analyzer/blockanalyzer.h
+++ b/src/analyzer/blockanalyzer.h
@@ -24,20 +24,17 @@
 #ifndef BLOCKANALYZER_H
 #define BLOCKANALYZER_H
 
-#include <vector>
-
 #include <QtGlobal>
 #include <QObject>
-#include <QWidget>
 #include <QVector>
 #include <QString>
 #include <QPixmap>
 #include <QPainter>
 #include <QPalette>
-#include <QtEvents>
 
 #include "analyzerbase.h"
 
+class QWidget;
 class QResizeEvent;
 
 class BlockAnalyzer : public Analyzer::Base {
diff --git a/src/analyzer/boomanalyzer.cpp b/src/analyzer/boomanalyzer.cpp
index aaabac4ed..a7cc15073 100644
--- a/src/analyzer/boomanalyzer.cpp
+++ b/src/analyzer/boomanalyzer.cpp
@@ -26,12 +26,17 @@
 
 #include <cmath>
 
-#include <QObject>
 #include <QWidget>
 #include <QPixmap>
 #include <QPainter>
+#include <QPalette>
 #include <QColor>
 
+#include "engine/engine_fwd.h"
+#include "engine/enginebase.h"
+#include "fht.h"
+#include "analyzerbase.h"
+
 using Analyzer::Scope;
 
 const uint BoomAnalyzer::kColumnWidth = 4;
diff --git a/src/analyzer/boomanalyzer.h b/src/analyzer/boomanalyzer.h
index fe2cc1a0d..e4a918d76 100644
--- a/src/analyzer/boomanalyzer.h
+++ b/src/analyzer/boomanalyzer.h
@@ -27,12 +27,13 @@
 
 #include "analyzerbase.h"
 
+#include <QtGlobal>
 #include <QObject>
-#include <QWidget>
 #include <QPixmap>
 #include <QPainter>
 #include <QColor>
 
+class QWidget;
 class QResizeEvent;
 
 class BoomAnalyzer : public Analyzer::Base {
diff --git a/src/analyzer/rainbowanalyzer.cpp b/src/analyzer/rainbowanalyzer.cpp
index 8ab503137..ca8c2eab1 100644
--- a/src/analyzer/rainbowanalyzer.cpp
+++ b/src/analyzer/rainbowanalyzer.cpp
@@ -27,17 +27,19 @@
 
 #include <cmath>
 
-#include <QObject>
+#include <QtGlobal>
 #include <QWidget>
 #include <QPixmap>
 #include <QPainter>
 #include <QColor>
 #include <QBrush>
 #include <QPen>
+#include <QPoint>
+#include <QSize>
 #include <QTimerEvent>
 
-#include "core/arraysize.h"
-#include "core/logging.h"
+#include "fht.h"
+#include "analyzerbase.h"
 
 using Analyzer::Scope;
 
diff --git a/src/analyzer/rainbowanalyzer.h b/src/analyzer/rainbowanalyzer.h
index ce65e6317..c1d4de113 100644
--- a/src/analyzer/rainbowanalyzer.h
+++ b/src/analyzer/rainbowanalyzer.h
@@ -30,9 +30,15 @@
 
 #include <QObject>
 #include <QWidget>
-#include <QDateTime>
+#include <QPixmap>
 #include <QPainter>
 #include <QPen>
+#include <QBrush>
+#include <QRect>
+
+class QWidget;
+class QTimerEvent;
+class QResizeEvent;
 
 namespace Rainbow {
 class RainbowAnalyzer : public Analyzer::Base {
diff --git a/src/collection/collection.cpp b/src/collection/collection.cpp
index f286740ed..ef04d0d73 100644
--- a/src/collection/collection.cpp
+++ b/src/collection/collection.cpp
@@ -21,11 +21,11 @@
 
 #include "config.h"
 
-#include <unistd.h>
-
+#include <QtGlobal>
 #include <QObject>
 #include <QThread>
 #include <QList>
+#include <QtDebug>
 
 #include "core/application.h"
 #include "core/database.h"
@@ -34,6 +34,7 @@
 #include "core/thread.h"
 #include "core/utilities.h"
 #include "core/song.h"
+#include "core/logging.h"
 #include "collection.h"
 #include "collectionwatcher.h"
 #include "collectionbackend.h"
diff --git a/src/collection/collection.h b/src/collection/collection.h
index 49c47ece9..25a940395 100644
--- a/src/collection/collection.h
+++ b/src/collection/collection.h
@@ -25,12 +25,14 @@
 #include "config.h"
 
 #include <QObject>
+#include <QList>
 #include <QHash>
 #include <QString>
-#include <QUrl>
 
 #include "core/song.h"
 
+class QThread;
+
 class Application;
 class Thread;
 class CollectionBackend;
diff --git a/src/collection/collectionbackend.cpp b/src/collection/collectionbackend.cpp
index 6cea2c052..b64f6a88d 100644
--- a/src/collection/collectionbackend.cpp
+++ b/src/collection/collectionbackend.cpp
@@ -30,23 +30,20 @@
 #include <QMutex>
 #include <QSet>
 #include <QMap>
-#include <QByteArray>
-#include <QFileInfo>
-#include <QDateTime>
+#include <QVector>
 #include <QVariant>
+#include <QByteArray>
 #include <QString>
 #include <QStringList>
-#include <QRegExp>
 #include <QUrl>
+#include <QFileInfo>
+#include <QDateTime>
+#include <QRegExp>
 #include <QSqlDatabase>
 #include <QSqlQuery>
-#include <QtDebug>
 
-#include "core/application.h"
 #include "core/database.h"
-#include "core/logging.h"
 #include "core/scopedtransaction.h"
-#include "core/utilities.h"
 
 #include "directory.h"
 #include "collectionbackend.h"
diff --git a/src/collection/collectionbackend.h b/src/collection/collectionbackend.h
index cdfad377e..7b47b0e46 100644
--- a/src/collection/collectionbackend.h
+++ b/src/collection/collectionbackend.h
@@ -24,13 +24,10 @@
 
 #include "config.h"
 
-
 #include <QtGlobal>
 #include <QObject>
 #include <QFileInfo>
 #include <QList>
-#include <QVector>
-#include <QSet>
 #include <QString>
 #include <QStringList>
 #include <QUrl>
diff --git a/src/collection/collectiondirectorymodel.cpp b/src/collection/collectiondirectorymodel.cpp
index 79842ccb3..ebdeb5ec5 100644
--- a/src/collection/collectiondirectorymodel.cpp
+++ b/src/collection/collectiondirectorymodel.cpp
@@ -25,9 +25,7 @@
 #include <QAbstractItemModel>
 #include <QVariant>
 #include <QString>
-#include <QUrl>
 
-#include "core/application.h"
 #include "core/filesystemmusicstorage.h"
 #include "core/iconloader.h"
 #include "core/musicstorage.h"
diff --git a/src/collection/collectionfilterwidget.cpp b/src/collection/collectionfilterwidget.cpp
index 077edbe6e..ec92b22b8 100644
--- a/src/collection/collectionfilterwidget.cpp
+++ b/src/collection/collectionfilterwidget.cpp
@@ -49,6 +49,7 @@
 #include "collectionfilterwidget.h"
 #include "groupbydialog.h"
 #include "ui_collectionfilterwidget.h"
+#include "widgets/qsearchfield.h"
 
 CollectionFilterWidget::CollectionFilterWidget(QWidget *parent)
     : QWidget(parent),
diff --git a/src/collection/collectionfilterwidget.h b/src/collection/collectionfilterwidget.h
index f9b58184f..66c9f60b2 100644
--- a/src/collection/collectionfilterwidget.h
+++ b/src/collection/collectionfilterwidget.h
@@ -29,7 +29,6 @@
 #include <QObject>
 #include <QMap>
 #include <QString>
-#include <QtEvents>
 
 #include "collectionquery.h"
 #include "collectionmodel.h"
@@ -44,7 +43,6 @@ class GroupByDialog;
 class SavedGroupingManager;
 class SettingsDialog;
 class Ui_CollectionFilterWidget;
-struct QueryOptions;
 
 class CollectionFilterWidget : public QWidget {
   Q_OBJECT
diff --git a/src/collection/collectionitemdelegate.cpp b/src/collection/collectionitemdelegate.cpp
index 8b5b16955..7bb1f97e7 100644
--- a/src/collection/collectionitemdelegate.cpp
+++ b/src/collection/collectionitemdelegate.cpp
@@ -21,11 +21,14 @@
 #include "config.h"
 
 #include <QtGlobal>
+#include <QAbstractItemModel>
 #include <QAbstractItemView>
 #include <QStyleOptionViewItem>
 #include <QVariant>
 #include <QString>
 #include <QLocale>
+#include <QPixmap>
+#include <QIcon>
 #include <QPainter>
 #include <QPalette>
 #include <QPen>
@@ -34,8 +37,7 @@
 #include <QBrush>
 #include <QColor>
 #include <QFont>
-#include <QPixmap>
-#include <QIcon>
+#include <QPoint>
 #include <QLinearGradient>
 #include <QToolTip>
 #include <QWhatsThis>
diff --git a/src/collection/collectionitemdelegate.h b/src/collection/collectionitemdelegate.h
index 8628cc53d..916847ad7 100644
--- a/src/collection/collectionitemdelegate.h
+++ b/src/collection/collectionitemdelegate.h
@@ -23,12 +23,13 @@
 
 #include "config.h"
 
-
+#include <QObject>
 #include <QStyledItemDelegate>
-#include <QAbstractItemView>
-#include <QPainter>
+#include <QStyleOption>
 #include <QStyleOptionViewItem>
 
+class QAbstractItemView;
+class QPainter;
 class QHelpEvent;
 
 class CollectionItemDelegate : public QStyledItemDelegate {
diff --git a/src/collection/collectionmodel.cpp b/src/collection/collectionmodel.cpp
index 30b4ae9b4..71b1dbad3 100644
--- a/src/collection/collectionmodel.cpp
+++ b/src/collection/collectionmodel.cpp
@@ -21,30 +21,32 @@
 
 #include "config.h"
 
+#include <memory>
 #include <functional>
 #include <algorithm>
 
 #include <QObject>
 #include <QtGlobal>
 #include <QtConcurrentRun>
-#include <QtAlgorithms>
+#include <QThread>
 #include <QMutex>
 #include <QFuture>
 #include <QDataStream>
 #include <QMimeData>
 #include <QIODevice>
-#include <QByteArray>
-#include <QVariant>
 #include <QList>
 #include <QSet>
 #include <QMap>
-#include <QChar>
-#include <QRegExp>
+#include <QVariant>
+#include <QByteArray>
 #include <QString>
 #include <QStringList>
 #include <QUrl>
 #include <QImage>
+#include <QChar>
+#include <QRegExp>
 #include <QPixmapCache>
+#include <QNetworkDiskCache>
 #include <QSettings>
 #include <QStandardPaths>
 #include <QtDebug>
diff --git a/src/collection/collectionmodel.h b/src/collection/collectionmodel.h
index d8e898621..5d73f218f 100644
--- a/src/collection/collectionmodel.h
+++ b/src/collection/collectionmodel.h
@@ -24,18 +24,16 @@
 
 #include "config.h"
 
-
 #include <QtGlobal>
 #include <QObject>
 #include <QAbstractItemModel>
 #include <QFuture>
 #include <QDataStream>
-#include <QList>
-#include <QMap>
 #include <QMetaType>
-#include <QMimeData>
 #include <QPair>
 #include <QSet>
+#include <QList>
+#include <QMap>
 #include <QVariant>
 #include <QString>
 #include <QStringList>
@@ -43,8 +41,6 @@
 #include <QImage>
 #include <QIcon>
 #include <QPixmap>
-#include <QNetworkDiskCache>
-#include <QSettings>
 
 #include "core/simpletreemodel.h"
 #include "core/song.h"
@@ -53,10 +49,12 @@
 #include "sqlrow.h"
 #include "covermanager/albumcoverloaderoptions.h"
 
+class QSettings;
+class QNetworkDiskCache;
+
 class Application;
 class CollectionBackend;
 class CollectionDirectoryModel;
-class CollectionItem;
 
 class CollectionModel : public SimpleTreeModel<CollectionItem> {
   Q_OBJECT
diff --git a/src/collection/collectionplaylistitem.cpp b/src/collection/collectionplaylistitem.cpp
index 651aa15b1..666321de9 100644
--- a/src/collection/collectionplaylistitem.cpp
+++ b/src/collection/collectionplaylistitem.cpp
@@ -21,7 +21,6 @@
 #include "config.h"
 
 #include <QVariant>
-#include <QString>
 #include <QUrl>
 
 #include "collectionplaylistitem.h"
diff --git a/src/collection/collectionplaylistitem.h b/src/collection/collectionplaylistitem.h
index aa501d330..f50d49375 100644
--- a/src/collection/collectionplaylistitem.h
+++ b/src/collection/collectionplaylistitem.h
@@ -23,9 +23,7 @@
 
 #include "config.h"
 
-
 #include <QVariant>
-#include <QString>
 #include <QUrl>
 
 #include "core/song.h"
diff --git a/src/collection/collectionquery.cpp b/src/collection/collectionquery.cpp
index 8202109e7..7f9066ff5 100644
--- a/src/collection/collectionquery.cpp
+++ b/src/collection/collectionquery.cpp
@@ -31,7 +31,6 @@
 #include <QSqlQuery>
 
 #include "collectionquery.h"
-#include "core/logging.h"
 #include "core/song.h"
 
 QueryOptions::QueryOptions() : max_age_(-1), query_mode_(QueryMode_All) {}
diff --git a/src/collection/collectionquery.h b/src/collection/collectionquery.h
index a9a69f82c..4cb11de55 100644
--- a/src/collection/collectionquery.h
+++ b/src/collection/collectionquery.h
@@ -23,7 +23,6 @@
 
 #include "config.h"
 
-
 #include <QMetaType>
 #include <QVariant>
 #include <QString>
@@ -32,7 +31,6 @@
 #include <QSqlQuery>
 
 class Song;
-class CollectionBackend;
 
 // This structure let's you customize behaviour of any CollectionQuery.
 struct QueryOptions {
diff --git a/src/collection/collectionview.cpp b/src/collection/collectionview.cpp
index c6e998fb9..e192ca8ac 100644
--- a/src/collection/collectionview.cpp
+++ b/src/collection/collectionview.cpp
@@ -22,37 +22,25 @@
 
 #include <QtGlobal>
 #include <QWidget>
+#include <QAbstractItemView>
+#include <QTreeView>
 #include <QItemSelectionModel>
 #include <QSortFilterProxyModel>
-#include <QAbstractItemView>
-#include <QStyleOptionViewItem>
-#include <QAction>
+#include <QMimeData>
+#include <QSet>
+#include <QList>
+#include <QMap>
 #include <QVariant>
 #include <QString>
 #include <QUrl>
-#include <QList>
-#include <QLocale>
-#include <QMap>
-#include <QMessageBox>
-#include <QMenu>
-#include <QMimeData>
+#include <QPixmap>
 #include <QPainter>
-#include <QPalette>
-#include <QPen>
-#include <QPoint>
 #include <QRect>
-#include <QSet>
-#include <QSize>
-#include <QToolTip>
-#include <QTreeView>
-#include <QWhatsThis>
-#include <QBrush>
-#include <QColor>
 #include <QFont>
 #include <QFontMetrics>
-#include <QPixmap>
-#include <QIcon>
-#include <QLinearGradient>
+#include <QMenu>
+#include <QAction>
+#include <QMessageBox>
 #include <QSettings>
 #include <QtEvents>
 
diff --git a/src/collection/collectionview.h b/src/collection/collectionview.h
index 1901a28c8..0de3df269 100644
--- a/src/collection/collectionview.h
+++ b/src/collection/collectionview.h
@@ -26,25 +26,19 @@
 #include <memory>
 
 #include <QObject>
-#include <QWidget>
 #include <QAbstractItemModel>
 #include <QAbstractItemView>
 #include <QString>
 #include <QPixmap>
-#include <QPainter>
 #include <QSet>
-#include <QStyleOption>
-#include <QStyledItemDelegate>
-#include <QStyleOptionViewItem>
-#include <QAction>
-#include <QMenu>
-#include <QtEvents>
 
 #include "core/song.h"
 #include "widgets/autoexpandingtreeview.h"
 
+class QWidget;
+class QMenu;
+class QAction;
 class QContextMenuEvent;
-class QHelpEvent;
 class QMouseEvent;
 class QPaintEvent;
 
diff --git a/src/collection/collectionwatcher.cpp b/src/collection/collectionwatcher.cpp
index 7d7c8969b..26dda636c 100644
--- a/src/collection/collectionwatcher.cpp
+++ b/src/collection/collectionwatcher.cpp
@@ -24,7 +24,6 @@
 #include <assert.h>
 
 #include <QObject>
-#include <QApplication>
 #include <QThread>
 #include <QIODevice>
 #include <QDir>
@@ -50,7 +49,6 @@
 #include "core/logging.h"
 #include "core/tagreaderclient.h"
 #include "core/taskmanager.h"
-#include "core/utilities.h"
 #include "directory.h"
 #include "collectionbackend.h"
 #include "collectionwatcher.h"
diff --git a/src/collection/collectionwatcher.h b/src/collection/collectionwatcher.h
index eb8e1f60a..7ce9d19be 100644
--- a/src/collection/collectionwatcher.h
+++ b/src/collection/collectionwatcher.h
@@ -24,7 +24,6 @@
 
 #include "config.h"
 
-
 #include <QtGlobal>
 #include <QObject>
 #include <QHash>
@@ -32,11 +31,14 @@
 #include <QSet>
 #include <QString>
 #include <QStringList>
-#include <QTimer>
+#include <QUrl>
 
 #include "directory.h"
 #include "core/song.h"
 
+class QThread;
+class QTimer;
+
 class CollectionBackend;
 class FileSystemWatcherInterface;
 class TaskManager;
diff --git a/src/collection/groupbydialog.cpp b/src/collection/groupbydialog.cpp
index 02424a519..28eac9319 100644
--- a/src/collection/groupbydialog.cpp
+++ b/src/collection/groupbydialog.cpp
@@ -23,10 +23,10 @@
 #include <functional>
 
 #include <QDialog>
+#include <QWidget>
 #include <QComboBox>
 #include <QDialogButtonBox>
 #include <QPushButton>
-#include <QWidget>
 
 #include "collectionmodel.h"
 #include "groupbydialog.h"
@@ -42,6 +42,7 @@ using std::placeholders::_2;
 #include <boost/multi_index/tag.hpp>
 #include <boost/multi_index_container.hpp>
 #include <boost/multi_index_container_fwd.hpp>
+#include <boost/multi_index/detail/ord_index_impl.hpp>
 #include <boost/operators.hpp>
 
 using boost::multi_index_container;
diff --git a/src/collection/groupbydialog.h b/src/collection/groupbydialog.h
index d1a97d417..68ec68d78 100644
--- a/src/collection/groupbydialog.h
+++ b/src/collection/groupbydialog.h
@@ -27,11 +27,12 @@
 
 #include <QDialog>
 #include <QObject>
-#include <QWidget>
 #include <QString>
 
 #include "collectionmodel.h"
 
+class QWidget;
+
 class GroupByDialogPrivate;
 class Ui_GroupByDialog;
 
diff --git a/src/collection/savedgroupingmanager.h b/src/collection/savedgroupingmanager.h
index 682f7e3dc..fafe7223c 100644
--- a/src/collection/savedgroupingmanager.h
+++ b/src/collection/savedgroupingmanager.h
@@ -25,12 +25,13 @@
 
 #include <QDialog>
 #include <QObject>
-#include <QWidget>
-#include <QStandardItemModel>
 #include <QString>
 
 #include "collectionmodel.h"
 
+class QWidget;
+class QStandardItemModel;
+
 class CollectionFilterWidget;
 class Ui_SavedGroupingManager;
 
diff --git a/src/context/contextalbumsmodel.cpp b/src/context/contextalbumsmodel.cpp
index 6669f9eb5..9c500068d 100644
--- a/src/context/contextalbumsmodel.cpp
+++ b/src/context/contextalbumsmodel.cpp
@@ -26,7 +26,6 @@
 
 #include <QObject>
 #include <QtGlobal>
-#include <QtAlgorithms>
 #include <QMutex>
 #include <QMimeData>
 #include <QVariant>
@@ -38,14 +37,10 @@
 #include <QUrl>
 #include <QImage>
 #include <QPixmapCache>
-#include <QSettings>
-#include <QtDebug>
 
 #include "core/application.h"
-#include "core/closure.h"
 #include "core/database.h"
 #include "core/iconloader.h"
-#include "core/logging.h"
 #include "collection/collectionquery.h"
 #include "collection/collectionbackend.h"
 #include "collection/collectionitem.h"
diff --git a/src/context/contextalbumsmodel.h b/src/context/contextalbumsmodel.h
index 96efd3fa0..1db28ee91 100644
--- a/src/context/contextalbumsmodel.h
+++ b/src/context/contextalbumsmodel.h
@@ -24,22 +24,20 @@
 
 #include "config.h"
 
-
 #include <QtGlobal>
 #include <QObject>
 #include <QAbstractItemModel>
-#include <QList>
-#include <QMap>
 #include <QPair>
 #include <QSet>
+#include <QList>
+#include <QMap>
 #include <QVariant>
 #include <QString>
 #include <QStringList>
 #include <QUrl>
 #include <QImage>
-#include <QIcon>
 #include <QPixmap>
-#include <QSettings>
+#include <QIcon>
 
 #include "core/simpletreemodel.h"
 #include "core/song.h"
diff --git a/src/context/contextalbumsview.cpp b/src/context/contextalbumsview.cpp
index d1ab58f14..26dec0d71 100644
--- a/src/context/contextalbumsview.cpp
+++ b/src/context/contextalbumsview.cpp
@@ -24,47 +24,30 @@
 #include <qcoreevent.h>
 
 #include <QtGlobal>
-#include <QWidget>
+#include <QTreeView>
 #include <QItemSelectionModel>
 #include <QSortFilterProxyModel>
 #include <QAbstractItemView>
 #include <QStyleOptionViewItem>
-#include <QAction>
+#include <QAbstractScrollArea>
+#include <QMimeData>
+#include <QList>
 #include <QVariant>
 #include <QString>
 #include <QUrl>
-#include <QList>
 #include <QLocale>
-#include <QMap>
 #include <QMessageBox>
 #include <QMenu>
-#include <QMimeData>
-#include <QPainter>
-#include <QPalette>
-#include <QPen>
-#include <QPoint>
+#include <QAction>
 #include <QRect>
-#include <QSet>
 #include <QSize>
 #include <QToolTip>
-#include <QTreeView>
-#include <QHeaderView>
 #include <QWhatsThis>
-#include <QBrush>
-#include <QColor>
-#include <QFont>
-#include <QFontMetrics>
-#include <QPixmap>
-#include <QIcon>
-#include <QLinearGradient>
-#include <QSettings>
-#include <QtEvents>
 
 #include "core/application.h"
 #include "core/iconloader.h"
 #include "core/mimedata.h"
 #include "core/utilities.h"
-#include "collection/collectionbackend.h"
 #include "collection/collectiondirectorymodel.h"
 #include "collection/collectionmodel.h"
 #include "collection/collectionitem.h"
@@ -74,9 +57,7 @@
 #endif
 #include "dialogs/edittagdialog.h"
 #include "organise/organisedialog.h"
-#include "settings/collectionsettingspage.h"
 
-#include "contextview.h"
 #include "contextalbumsmodel.h"
 #include "contextalbumsview.h"
 
diff --git a/src/context/contextalbumsview.h b/src/context/contextalbumsview.h
index eb0804c8f..fbd6eef16 100644
--- a/src/context/contextalbumsview.h
+++ b/src/context/contextalbumsview.h
@@ -27,23 +27,24 @@
 #include <memory>
 
 #include <QObject>
-#include <QWidget>
 #include <QAbstractItemModel>
 #include <QAbstractItemView>
-#include <QString>
-#include <QPixmap>
-#include <QPainter>
-#include <QSet>
-#include <QStyleOption>
 #include <QStyledItemDelegate>
-#include <QStyleOptionViewItem>
-#include <QAction>
-#include <QMenu>
-#include <QtEvents>
+#include <QStyleOption>
+#include <QSet>
+#include <QString>
 
 #include "core/song.h"
 #include "widgets/autoexpandingtreeview.h"
 
+class QWidget;
+class QMenu;
+class QAction;
+class QContextMenuEvent;
+class QHelpEvent;
+class QMouseEvent;
+class QPaintEvent;
+
 class Application;
 class EditTagDialog;
 class OrganiseDialog;
diff --git a/src/context/contextview.cpp b/src/context/contextview.cpp
index f335c3497..9d2455eaf 100644
--- a/src/context/contextview.cpp
+++ b/src/context/contextview.cpp
@@ -22,28 +22,32 @@
 #include <QtGlobal>
 #include <QObject>
 #include <QWidget>
-#include <QIODevice>
-#include <QFile>
 #include <QByteArray>
 #include <QList>
 #include <QVariant>
 #include <QString>
+#include <QUrl>
 #include <QImage>
 #include <QPixmap>
+#include <QIcon>
 #include <QMovie>
-#include <QAction>
 #include <QPainter>
 #include <QPalette>
 #include <QBrush>
+#include <QSize>
 #include <QMenu>
+#include <QAction>
 #include <QSettings>
 #include <QSizePolicy>
 #include <QTimeLine>
 #include <QtEvents>
 #include <QFontDatabase>
+#include <QLabel>
+#include <QLayoutItem>
+#include <QGridLayout>
+#include <QStackedWidget>
 
 #include "core/application.h"
-#include "core/logging.h"
 #include "core/player.h"
 #include "core/song.h"
 #include "core/utilities.h"
@@ -53,20 +57,17 @@
 #include "engine/enginetype.h"
 #include "engine/devicefinders.h"
 #include "engine/devicefinder.h"
-#include "collection/collection.h"
 #include "collection/collectionbackend.h"
 #include "collection/collectionquery.h"
-#include "collection/collectionmodel.h"
 #include "collection/collectionview.h"
 #include "covermanager/albumcoverchoicecontroller.h"
 #include "covermanager/albumcoverloader.h"
-#include "covermanager/currentalbumcoverloader.h"
 #include "lyrics/lyricsfetcher.h"
 #include "settings/contextsettingspage.h"
-#include "widgets/osd.h"
 
 #include "contextview.h"
 #include "contextalbumsmodel.h"
+#include "contextalbumsview.h"
 #include "ui_contextviewcontainer.h"
 
 using std::unique_ptr;
diff --git a/src/context/contextview.h b/src/context/contextview.h
index aed4c1c92..1578ada3c 100644
--- a/src/context/contextview.h
+++ b/src/context/contextview.h
@@ -30,13 +30,7 @@
 #include <QString>
 #include <QImage>
 #include <QPixmap>
-#include <QPainter>
 #include <QMovie>
-#include <QTimeLine>
-#include <QAction>
-#include <QMenu>
-#include <QLabel>
-#include <QtEvents>
 
 #include "core/song.h"
 #include "covermanager/albumcoverloaderoptions.h"
@@ -45,6 +39,17 @@
 
 using std::unique_ptr;
 
+class QTimeLine;
+class QPainter;
+class QMenu;
+class QAction;
+class QLabel;
+class QEvent;
+class QContextMenuEvent;
+class QMouseEvent;
+class QDragEnterEvent;
+class QDropEvent;
+
 class Application;
 class CollectionView;
 class CollectionModel;
diff --git a/src/core/application.cpp b/src/core/application.cpp
index 062810e1e..645e6bb72 100644
--- a/src/core/application.cpp
+++ b/src/core/application.cpp
@@ -35,6 +35,7 @@
 #include "core/lazy.h"
 #include "core/tagreaderclient.h"
 #include "core/song.h"
+#include "core/logging.h"
 
 #include "database.h"
 #include "taskmanager.h"
@@ -57,7 +58,6 @@
 #include "covermanager/deezercoverprovider.h"
 
 #include "lyrics/lyricsproviders.h"
-#include "lyrics/lyricsprovider.h"
 #include "lyrics/auddlyricsprovider.h"
 #include "lyrics/ovhlyricsprovider.h"
 #include "lyrics/lololyricsprovider.h"
diff --git a/src/core/application.h b/src/core/application.h
index d94d5fb2a..d6f44ab79 100644
--- a/src/core/application.h
+++ b/src/core/application.h
@@ -28,7 +28,6 @@
 #include <memory>
 
 #include <QObject>
-#include <QThread>
 #include <QList>
 #include <QString>
 
@@ -36,6 +35,8 @@
 
 using std::unique_ptr;
 
+class QThread;
+
 class TaskManager;
 class ApplicationImpl;
 class TagReaderClient;
diff --git a/src/core/commandlineoptions.cpp b/src/core/commandlineoptions.cpp
index 11045ae83..b54ded8e5 100644
--- a/src/core/commandlineoptions.cpp
+++ b/src/core/commandlineoptions.cpp
@@ -24,6 +24,7 @@
 #include <cstdlib>
 #include <getopt.h>
 #include <iostream>
+#include <type_traits>
 
 #include <QtGlobal>
 #include <QObject>
diff --git a/src/core/database.cpp b/src/core/database.cpp
index a2489f0fd..31734b29a 100644
--- a/src/core/database.cpp
+++ b/src/core/database.cpp
@@ -21,6 +21,7 @@
 
 #include "config.h"
 
+#include <stddef.h>
 #include <assert.h>
 #include <sqlite3.h>
 #include <boost/scope_exit.hpp>
@@ -31,7 +32,6 @@
 #include <QIODevice>
 #include <QDir>
 #include <QFile>
-#include <QChar>
 #include <QList>
 #include <QByteArray>
 #include <QVariant>
@@ -43,7 +43,6 @@
 #include <QSqlDriver>
 #include <QSqlDatabase>
 #include <QSqlQuery>
-#include <QSqlResult>
 #include <QSqlError>
 #include <QStandardPaths>
 #include <QtDebug>
diff --git a/src/core/database.h b/src/core/database.h
index 0594ae5ad..5e4bf6685 100644
--- a/src/core/database.h
+++ b/src/core/database.h
@@ -29,8 +29,6 @@
 #include <QtGlobal>
 #include <QObject>
 #include <QMutex>
-#include <QByteArray>
-#include <QList>
 #include <QMap>
 #include <QSqlDatabase>
 #include <QSqlQuery>
diff --git a/src/core/deletefiles.h b/src/core/deletefiles.h
index 0ab1485bc..3b5306cf4 100644
--- a/src/core/deletefiles.h
+++ b/src/core/deletefiles.h
@@ -26,12 +26,11 @@
 #include <memory>
 
 #include <QObject>
-#include <QThread>
-#include <QString>
 #include <QStringList>
 
 #include "song.h"
 
+class QThread;
 class TaskManager;
 class MusicStorage;
 
diff --git a/src/core/iconloader.h b/src/core/iconloader.h
index 7c8c0f299..68f198c47 100644
--- a/src/core/iconloader.h
+++ b/src/core/iconloader.h
@@ -20,7 +20,6 @@
 #ifndef ICONLOADER_H
 #define ICONLOADER_H
 
-#include <QList>
 #include <QString>
 #include <QIcon>
 
diff --git a/src/core/mainwindow.cpp b/src/core/mainwindow.cpp
index 396eda181..cc30db5e3 100644
--- a/src/core/mainwindow.cpp
+++ b/src/core/mainwindow.cpp
@@ -23,12 +23,14 @@
 
 #include <memory>
 #include <functional>
+#include <algorithm>
 #include <cmath>
 
 #include <QMainWindow>
 #include <QApplication>
 #include <QObject>
 #include <QWidget>
+#include <QThread>
 #include <QSystemTrayIcon>
 #include <QSortFilterProxyModel>
 #include <QByteArray>
@@ -47,7 +49,6 @@
 #include <QMimeData>
 #include <QPalette>
 #include <QTimer>
-#include <QtAlgorithms>
 #include <QKeySequence>
 #include <QMenu>
 #include <QAction>
@@ -56,7 +57,16 @@
 #include <QMessageBox>
 #include <QtEvents>
 #include <QSettings>
-#include <QtDebug>
+#include <QColor>
+#include <QFrame>
+#include <QItemSelectionModel>
+#include <QLabel>
+#include <QLayout>
+#include <QSize>
+#include <QSplitter>
+#include <QStackedWidget>
+#include <QTabBar>
+#include <QToolButton>
 
 #include "core/logging.h"
 #include "core/closure.h"
@@ -80,6 +90,7 @@
 #include "appearance.h"
 #include "engine/enginetype.h"
 #include "engine/enginebase.h"
+#include "engine/engine_fwd.h"
 #include "dialogs/errordialog.h"
 #include "dialogs/about.h"
 #include "dialogs/console.h"
@@ -94,7 +105,7 @@
 #include "widgets/osd.h"
 #include "widgets/trackslider.h"
 #include "context/contextview.h"
-#include "collection/collectionview.h"
+#include "context/contextalbumsview.h"
 #include "collection/collection.h"
 #include "collection/collectionbackend.h"
 #include "collection/collectiondirectorymodel.h"
@@ -138,11 +149,9 @@
 #  include "settings/tidalsettingspage.h"
 #endif
 #ifdef HAVE_QOBUZ
-#  include "qobuz/qobuzservice.h"
 #  include "settings/qobuzsettingspage.h"
 #endif
 #ifdef HAVE_SUBSONIC
-#  include "subsonic/subsonicservice.h"
 #  include "settings/subsonicsettingspage.h"
 #endif
 
@@ -150,6 +159,8 @@
 #include "internet/internetservice.h"
 #include "internet/internetsongsview.h"
 #include "internet/internettabsview.h"
+#include "internet/internetcollectionview.h"
+#include "internet/internetsearchview.h"
 
 #include "scrobbler/audioscrobbler.h"
 
diff --git a/src/core/mainwindow.h b/src/core/mainwindow.h
index 2e3ab64f9..b85ac4970 100644
--- a/src/core/mainwindow.h
+++ b/src/core/mainwindow.h
@@ -39,8 +39,10 @@
 #include <QPoint>
 #include <QMimeData>
 #include <QList>
+#include <QByteArray>
 #include <QString>
 #include <QUrl>
+#include <QImage>
 #include <QPixmap>
 #include <QTimer>
 #include <QSettings>
@@ -48,6 +50,7 @@
 
 #include "core/lazy.h"
 #include "core/tagreaderclient.h"
+#include "core/song.h"
 #include "engine/enginetype.h"
 #include "engine/engine_fwd.h"
 #include "mac_startup.h"
@@ -67,7 +70,6 @@ class CollectionViewContainer;
 class AlbumCoverChoiceController;
 class CommandlineOptions;
 #ifndef Q_OS_WIN
-class DeviceView;
 class DeviceViewContainer;
 #endif
 class EditTagDialog;
@@ -79,7 +81,6 @@ class MimeData;
 class OrganiseDialog;
 class PlaylistListContainer;
 class QueueView;
-class Song;
 class SystemTrayIcon;
 #if defined(HAVE_GSTREAMER) && defined(HAVE_CHROMAPRINT)
 class TagFetcher;
diff --git a/src/core/mergedproxymodel.cpp b/src/core/mergedproxymodel.cpp
index d9abfd120..0aa175d06 100644
--- a/src/core/mergedproxymodel.cpp
+++ b/src/core/mergedproxymodel.cpp
@@ -23,8 +23,11 @@
 #include <functional>
 #include <limits>
 
+#include <boost/multi_index/detail/ord_index_impl.hpp>
+
 #include <QObject>
 #include <QMimeData>
+#include <QList>
 #include <QStringList>
 #include <QtAlgorithms>
 #include <QAbstractItemModel>
diff --git a/src/core/mergedproxymodel.h b/src/core/mergedproxymodel.h
index 8699cefc6..2fc309114 100644
--- a/src/core/mergedproxymodel.h
+++ b/src/core/mergedproxymodel.h
@@ -27,15 +27,15 @@
 #include <cstddef>
 
 #include <QObject>
-#include <QMimeData>
 #include <QAbstractItemModel>
 #include <QAbstractProxyModel>
-#include <QPersistentModelIndex>
 #include <QMap>
 #include <QVariant>
 #include <QString>
 #include <QStringList>
 
+class QMimeData;
+
 std::size_t hash_value(const QModelIndex &index);
 
 class MergedProxyModelPrivate;
diff --git a/src/core/metatypes.cpp b/src/core/metatypes.cpp
index cec8783e0..e01ad7803 100644
--- a/src/core/metatypes.cpp
+++ b/src/core/metatypes.cpp
@@ -27,7 +27,7 @@
 #  include <gst/gstelement.h>
 #endif
 
-#include <QtGlobal>
+#include <QDataStream>
 #include <QAbstractSocket>
 #include <QMetaType>
 #include <QFileInfo>
diff --git a/src/core/multisortfilterproxy.cpp b/src/core/multisortfilterproxy.cpp
index e1b474f5b..c4a4cd0e9 100644
--- a/src/core/multisortfilterproxy.cpp
+++ b/src/core/multisortfilterproxy.cpp
@@ -22,11 +22,13 @@
 
 #include <QtGlobal>
 #include <QObject>
+#include <QAbstractItemModel>
 #include <QSortFilterProxyModel>
 #include <QMetaType>
 #include <QDateTime>
 #include <QVariant>
 #include <QString>
+#include <QChar>
 
 #include "multisortfilterproxy.h"
 
diff --git a/src/core/multisortfilterproxy.h b/src/core/multisortfilterproxy.h
index 04457b0e7..2410c3c94 100644
--- a/src/core/multisortfilterproxy.h
+++ b/src/core/multisortfilterproxy.h
@@ -23,13 +23,13 @@
 
 #include "config.h"
 
-
-#include <QObject>
 #include <QSortFilterProxyModel>
 #include <QList>
 #include <QPair>
 #include <QVariant>
 
+class QObject;
+
 class MultiSortFilterProxy : public QSortFilterProxyModel {
  public:
   MultiSortFilterProxy(QObject *parent = nullptr);
diff --git a/src/core/musicstorage.h b/src/core/musicstorage.h
index 771d5d464..ec6f1faa5 100644
--- a/src/core/musicstorage.h
+++ b/src/core/musicstorage.h
@@ -23,6 +23,8 @@
 
 #include "config.h"
 
+#include <QtGlobal>
+
 #include <functional>
 #include <memory>
 
diff --git a/src/core/network.cpp b/src/core/network.cpp
index 978a26988..074d380be 100644
--- a/src/core/network.cpp
+++ b/src/core/network.cpp
@@ -21,12 +21,16 @@
 
 #include "config.h"
 
+#include <type_traits>
+
 #include <QtGlobal>
 #include <QObject>
 #include <QCoreApplication>
 #include <QStandardPaths>
 #include <QIODevice>
 #include <QMutex>
+#include <QVariant>
+#include <QByteArray>
 #include <QString>
 #include <QUrl>
 #include <QNetworkAccessManager>
@@ -42,8 +46,7 @@ QMutex ThreadSafeNetworkDiskCache::sMutex;
 ThreadSafeNetworkDiskCache *ThreadSafeNetworkDiskCache::sInstance = nullptr;
 QNetworkDiskCache *ThreadSafeNetworkDiskCache::sCache = nullptr;
 
-ThreadSafeNetworkDiskCache::ThreadSafeNetworkDiskCache(QObject *parent)
-: QAbstractNetworkCache(parent) {
+ThreadSafeNetworkDiskCache::ThreadSafeNetworkDiskCache(QObject *parent) : QAbstractNetworkCache(parent) {
 
   QMutexLocker l(&sMutex);
   if (!sCache) {
diff --git a/src/core/network.h b/src/core/network.h
index 00905fab6..be685ebca 100644
--- a/src/core/network.h
+++ b/src/core/network.h
@@ -24,19 +24,19 @@
 
 #include "config.h"
 
-
 #include <QtGlobal>
 #include <QObject>
 #include <QNetworkAccessManager>
 #include <QAbstractNetworkCache>
-#include <QIODevice>
 #include <QMutex>
 #include <QUrl>
 #include <QNetworkRequest>
-#include <QNetworkReply>
-#include <QNetworkDiskCache>
 #include <QNetworkCacheMetaData>
 
+class QIODevice;
+class QNetworkReply;
+class QNetworkDiskCache;
+
 class NetworkAccessManager : public QNetworkAccessManager {
   Q_OBJECT
 
diff --git a/src/core/networkproxyfactory.h b/src/core/networkproxyfactory.h
index fa6ff30c0..3b35554a5 100644
--- a/src/core/networkproxyfactory.h
+++ b/src/core/networkproxyfactory.h
@@ -23,7 +23,6 @@
 
 #include "config.h"
 
-
 #include <QtGlobal>
 #include <QMutex>
 #include <QList>
diff --git a/src/core/networktimeouts.h b/src/core/networktimeouts.h
index 2e4aa6115..b1c40e56f 100644
--- a/src/core/networktimeouts.h
+++ b/src/core/networktimeouts.h
@@ -23,7 +23,6 @@
 
 #include "config.h"
 
-
 #include <QtGlobal>
 #include <QObject>
 #include <QMap>
diff --git a/src/core/player.h b/src/core/player.h
index a61997d74..b34088e95 100644
--- a/src/core/player.h
+++ b/src/core/player.h
@@ -37,9 +37,6 @@
 #include "urlhandler.h"
 #include "engine/engine_fwd.h"
 #include "engine/enginetype.h"
-#ifdef HAVE_GSTREAMER
-#include "engine/gststartup.h"
-#endif
 #include "playlist/playlistitem.h"
 #include "settings/behavioursettingspage.h"
 
@@ -47,6 +44,9 @@ class Application;
 class Song;
 class AnalyzerContainer;
 class Equalizer;
+#ifdef HAVE_GSTREAMER
+class GstStartup;
+#endif
 
 using std::unique_ptr;
 
diff --git a/src/core/qtfslistener.cpp b/src/core/qtfslistener.cpp
index 0c0af194c..2394763ef 100644
--- a/src/core/qtfslistener.cpp
+++ b/src/core/qtfslistener.cpp
@@ -23,8 +23,6 @@
 #include <QFileSystemWatcher>
 #include <QString>
 
-#include "core/logging.h"
-
 #include "filesystemwatcherinterface.h"
 #include "qtfslistener.h"
 
diff --git a/src/core/qtsystemtrayicon.h b/src/core/qtsystemtrayicon.h
index 1dab067ed..fc426c5fe 100644
--- a/src/core/qtsystemtrayicon.h
+++ b/src/core/qtsystemtrayicon.h
@@ -23,18 +23,18 @@
 
 #include "config.h"
 
-
 #include <QObject>
 #include <QSystemTrayIcon>
 #include <QString>
 #include <QUrl>
+#include <QIcon>
 #include <QPixmap>
 #include <QAction>
-#include <QMenu>
 #include <QtEvents>
 
 #include "systemtrayicon.h"
 
+class QMenu;
 class QEvent;
 
 class Song;
diff --git a/src/core/scangiomodulepath.cpp b/src/core/scangiomodulepath.cpp
index 4ee02540f..4a9636713 100644
--- a/src/core/scangiomodulepath.cpp
+++ b/src/core/scangiomodulepath.cpp
@@ -22,7 +22,6 @@
 
 #include <gio/gio.h>
 
-#include <QApplication>
 #include <QCoreApplication>
 #include <QDir>
 #include <QByteArray>
@@ -32,6 +31,7 @@
 #include "core/logging.h"
 
 void ScanGIOModulePath() {
+
   QString gio_module_path;
 
 #if defined(Q_OS_WIN32)
@@ -43,4 +43,5 @@ void ScanGIOModulePath() {
     QByteArray bytes = gio_module_path.toLocal8Bit();
     g_io_modules_scan_all_in_directory(bytes.data());
   }
+
 }
diff --git a/src/core/scopedtransaction.h b/src/core/scopedtransaction.h
index 274ce6a53..9b679f41a 100644
--- a/src/core/scopedtransaction.h
+++ b/src/core/scopedtransaction.h
@@ -25,7 +25,7 @@
 
 #include <boost/noncopyable.hpp>
 
-#include <QSqlDatabase>
+class QSqlDatabase;
 
 // Opens a transaction on a database.
 // Rolls back the transaction if the object goes out of scope before Commit() is called.
diff --git a/src/core/song.cpp b/src/core/song.cpp
index d7bca02c0..69cde36b0 100644
--- a/src/core/song.cpp
+++ b/src/core/song.cpp
@@ -27,12 +27,10 @@
 #include <taglib/id3v1genres.h>
 
 #include <QtGlobal>
-#include <QCoreApplication>
 #include <QObject>
 #include <QFile>
 #include <QFileInfo>
 #include <QSharedData>
-#include <QtAlgorithms>
 #include <QHash>
 #include <QByteArray>
 #include <QVariant>
diff --git a/src/core/song.h b/src/core/song.h
index b0fbd9e06..090164589 100644
--- a/src/core/song.h
+++ b/src/core/song.h
@@ -38,8 +38,9 @@
 #include <QUrl>
 #include <QImage>
 #include <QIcon>
-#include <QTextCodec>
-#include <QSqlQuery>
+
+class QTextCodec;
+class QSqlQuery;
 
 namespace Engine {
 struct SimpleMetaBundle;
diff --git a/src/core/songloader.cpp b/src/core/songloader.cpp
index d0db8b6de..ffe91d229 100644
--- a/src/core/songloader.cpp
+++ b/src/core/songloader.cpp
@@ -33,7 +33,6 @@
 #include <QIODevice>
 #include <QBuffer>
 #include <QByteArray>
-#include <QtAlgorithms>
 #include <QDir>
 #include <QDirIterator>
 #include <QFile>
diff --git a/src/core/songloader.h b/src/core/songloader.h
index c43ab8dac..4ac5bb3a9 100644
--- a/src/core/songloader.h
+++ b/src/core/songloader.h
@@ -40,10 +40,10 @@
 #include <QString>
 #include <QStringList>
 #include <QUrl>
-#include <QTimer>
 
 #include "song.h"
 
+class QTimer;
 class Player;
 class CollectionBackendInterface;
 class PlaylistParser;
diff --git a/src/core/standarditemiconloader.cpp b/src/core/standarditemiconloader.cpp
index 88cabf93b..468851251 100644
--- a/src/core/standarditemiconloader.cpp
+++ b/src/core/standarditemiconloader.cpp
@@ -23,9 +23,9 @@
 #include <QtGlobal>
 #include <QObject>
 #include <QAbstractItemModel>
+#include <QStandardItem>
 #include <QMap>
 #include <QSet>
-#include <QString>
 #include <QImage>
 #include <QPixmap>
 #include <QIcon>
diff --git a/src/core/standarditemiconloader.h b/src/core/standarditemiconloader.h
index a0f2d7b33..dbf701a7d 100644
--- a/src/core/standarditemiconloader.h
+++ b/src/core/standarditemiconloader.h
@@ -26,13 +26,13 @@
 #include <QtGlobal>
 #include <QObject>
 #include <QMap>
-#include <QString>
 #include <QImage>
-#include <QStandardItem>
-#include <QAbstractItemModel>
 
 #include "covermanager/albumcoverloaderoptions.h"
 
+class QAbstractItemModel;
+class QStandardItem;
+
 class Song;
 class AlbumCoverLoader;
 
diff --git a/src/core/stylesheetloader.cpp b/src/core/stylesheetloader.cpp
index 1f1ade129..41a5de181 100644
--- a/src/core/stylesheetloader.cpp
+++ b/src/core/stylesheetloader.cpp
@@ -21,13 +21,16 @@
 
 #include "config.h"
 
+#include <QtGlobal>
 #include <QObject>
 #include <QWidget>
 #include <QIODevice>
+#include <QTextStream>
 #include <QFile>
 #include <QString>
 #include <QColor>
 #include <QPalette>
+#include <QEvent>
 #include <QtDebug>
 
 #include "core/logging.h"
diff --git a/src/core/stylesheetloader.h b/src/core/stylesheetloader.h
index fa1fe03c8..8e677dcb5 100644
--- a/src/core/stylesheetloader.h
+++ b/src/core/stylesheetloader.h
@@ -24,14 +24,15 @@
 
 #include "config.h"
 
-
 #include <QObject>
-#include <QWidget>
-#include <QEvent>
+#include <QPair>
 #include <QMap>
 #include <QPalette>
 #include <QString>
 
+class QWidget;
+class QEvent;
+
 class StyleSheetLoader : public QObject {
  public:
   explicit StyleSheetLoader(QObject *parent = nullptr);
diff --git a/src/core/systemtrayicon.h b/src/core/systemtrayicon.h
index bcc21a5aa..a19a49237 100644
--- a/src/core/systemtrayicon.h
+++ b/src/core/systemtrayicon.h
@@ -23,11 +23,12 @@
 
 #include "config.h"
 
-
+#include <QtGlobal>
 #include <QObject>
 #include <QString>
 #include <QPixmap>
-#include <QAction>
+
+class QAction;
 
 class Song;
 
diff --git a/src/core/thread.h b/src/core/thread.h
index 35d193387..796d4a95c 100644
--- a/src/core/thread.h
+++ b/src/core/thread.h
@@ -20,11 +20,12 @@
 
 #include "config.h"
 
-#include <QObject>
 #include <QThread>
 
 #include "utilities.h"
 
+class QObject;
+
 // Improve QThread by adding a SetIoPriority function
 class Thread : public QThread {
  public:
diff --git a/src/core/translations.h b/src/core/translations.h
index 6b4bac44a..b81703a93 100644
--- a/src/core/translations.h
+++ b/src/core/translations.h
@@ -20,10 +20,11 @@
 #include "config.h"
 
 #include <QObject>
-#include <QTranslator>
 #include <QList>
 #include <QString>
 
+class QTranslator;
+
 class Translations : public QObject {
  public:
   Translations();
diff --git a/src/core/utilities.cpp b/src/core/utilities.cpp
index 0267e1f49..144fa1659 100644
--- a/src/core/utilities.cpp
+++ b/src/core/utilities.cpp
@@ -42,18 +42,19 @@
 #include <QFile>
 #include <QFileInfo>
 #include <QHostAddress>
-#include <QPoint>
-#include <QRect>
-#include <QSize>
-#include <QMap>
-#include <QList>
 #include <QSet>
+#include <QList>
+#include <QMap>
+#include <QVariant>
 #include <QString>
 #include <QStringList>
+#include <QUrl>
 #include <QRegExp>
 #include <QTcpServer>
 #include <QTemporaryFile>
-#include <QUrl>
+#include <QPoint>
+#include <QRect>
+#include <QSize>
 #include <QMetaEnum>
 #include <QXmlStreamReader>
 #include <QSettings>
@@ -62,6 +63,8 @@
 #include <QNetworkInterface>
 #include <QtDebug>
 
+#include <stdio.h>
+
 #ifdef Q_OS_LINUX
 #  include <unistd.h>
 #  include <sys/syscall.h>
diff --git a/src/core/utilities.h b/src/core/utilities.h
index bc42be2d6..60d5984a7 100644
--- a/src/core/utilities.h
+++ b/src/core/utilities.h
@@ -27,8 +27,6 @@
 #include <memory>
 
 #include <QtGlobal>
-#include <QWidget>
-#include <QIODevice>
 #include <QByteArray>
 #include <QFile>
 #include <QSize>
@@ -40,11 +38,14 @@
 #include <QStringList>
 #include <QUrl>
 #include <QColor>
-#include <QXmlStreamReader>
 #include <QtEvents>
 
 #include "core/song.h"
 
+class QWidget;
+class QIODevice;
+class QXmlStreamReader;
+
 namespace Utilities {
 QString PrettyTime(int seconds);
 QString PrettyTimeDelta(int seconds);
diff --git a/src/engine/devicefinders.cpp b/src/engine/devicefinders.cpp
index af87d3359..efe59e424 100644
--- a/src/engine/devicefinders.cpp
+++ b/src/engine/devicefinders.cpp
@@ -19,7 +19,6 @@
 
 #include "config.h"
 
-#include <QtGlobal>
 #include <QtAlgorithms>
 #include <QObject>
 #include <QList>
diff --git a/src/engine/enginetype.cpp b/src/engine/enginetype.cpp
index 0a4db9fc0..1e68014bd 100644
--- a/src/engine/enginetype.cpp
+++ b/src/engine/enginetype.cpp
@@ -19,7 +19,6 @@
 
 #include "config.h"
 
-#include <QObject>
 #include <QString>
 
 #include "enginetype.h"
diff --git a/src/equalizer/equalizer.cpp b/src/equalizer/equalizer.cpp
index f85c1efad..db4634cc0 100644
--- a/src/equalizer/equalizer.cpp
+++ b/src/equalizer/equalizer.cpp
@@ -41,8 +41,8 @@
 #include <QToolButton>
 #include <QCheckBox>
 #include <QComboBox>
+#include <QBoxLayout>
 #include <QSettings>
-#include <QtEvents>
 
 #include "core/iconloader.h"
 #include "equalizer.h"
diff --git a/src/equalizer/equalizer.h b/src/equalizer/equalizer.h
index 78a1268c8..9f60dddaf 100644
--- a/src/equalizer/equalizer.h
+++ b/src/equalizer/equalizer.h
@@ -26,13 +26,13 @@
 
 #include <QObject>
 #include <QDialog>
-#include <QWidget>
 #include <QList>
 #include <QMap>
 #include <QMetaType>
 #include <QDataStream>
 #include <QString>
 
+class QWidget;
 class QCloseEvent;
 
 class EqualizerSlider;
diff --git a/src/equalizer/equalizerslider.cpp b/src/equalizer/equalizerslider.cpp
index 5b966292b..c0a5457e3 100644
--- a/src/equalizer/equalizerslider.cpp
+++ b/src/equalizer/equalizerslider.cpp
@@ -20,9 +20,11 @@
 
 #include "config.h"
 
+#include <QtGlobal>
 #include <QWidget>
 #include <QString>
 #include <QLabel>
+#include <QFontMetrics>
 
 #include "widgets/stickyslider.h"
 #include "equalizerslider.h"
diff --git a/src/playlist/playlistbackend.h b/src/playlist/playlistbackend.h
index dcffbadd5..b10abea8f 100644
--- a/src/playlist/playlistbackend.h
+++ b/src/playlist/playlistbackend.h
@@ -32,7 +32,6 @@
 #include <QList>
 #include <QSet>
 #include <QString>
-#include <QVector>
 #include <QSqlQuery>
 
 #include "core/song.h"