Merge branch 'master' of git@github.com:mixxxdj/mixxx.git into new-signals-slots-syntax-library

# Conflicts:
#	src/library/library.cpp
#	src/library/scanner/libraryscanner.cpp

63 files changed, 1720 insertions, 382 deletions

diff --git a/build/depends.py b/build/depends.py
index a127271a46..3cb0980d8b 100644
--- a/build/depends.py
+++ b/build/depends.py
@@ -975,6 +975,7 @@ class MixxxCore(Feature):
                    "src/database/schemamanager.cpp",
 
                    "src/library/trackcollection.cpp",
+                   "src/library/externaltrackcollection.cpp",
                    "src/library/basesqltablemodel.cpp",
                    "src/library/basetrackcache.cpp",
                    "src/library/columncache.cpp",
diff --git a/default.nix b/default.nix
index 1b674e0041..165206dc65 100644
--- a/default.nix
+++ b/default.nix
@@ -1,4 +1,7 @@
-{ nixroot  ? (import <nixpkgs> {}) }:
+{ nixroot  ? (import <nixpkgs> {})
+, defaultLv2Plugins ? false
+, lv2Plugins ? []
+}:
 let inherit (nixroot) stdenv pkgs lib
     chromaprint fftw flac libid3tag libmad libopus libshout libsndfile lilv 
     libusb1 libvorbis libebur128 pkgconfig portaudio portmidi protobuf qt5 glib
@@ -42,7 +45,7 @@ let inherit (nixroot) stdenv pkgs lib
 
   shell-run = nixroot.writeShellScriptBin "run" ''
       BUILDDIR=$(ls -1 -d -t lin64_build lin_build | head -1)
-      $BUILDDIR/mixxx --settingsPath ./devsettings/ --resourcePath ./res "$@"
+      /usr/bin/env LV2_PATH=${lib.makeSearchPathOutput "lib" "lib/lv2" allLv2Plugins}:$LV2_PATH $BUILDDIR/mixxx --settingsPath ./devsettings/ --resourcePath ./res "$@"
   '';
 
   shell-debug = nixroot.writeShellScriptBin "debug" ''
@@ -50,6 +53,11 @@ let inherit (nixroot) stdenv pkgs lib
       gdb --args $BUILDDIR/mixxx --settingsPath ./devsettings/ --resourcePath ./res "$@"
   '';
 
+  allLv2Plugins = lv2Plugins ++ (if defaultLv2Plugins then [
+    nixroot.x42-plugins nixroot.zam-plugins nixroot.rkrlv2 nixroot.mod-distortion
+    nixroot.infamousPlugins nixroot.artyFX
+  ] else []);
+
 in stdenv.mkDerivation rec {
   name = "mixxx-${version}";
   # reading the version from git output is very hard to do without wasting lots of diskspace and runtime
@@ -83,7 +91,7 @@ in stdenv.mkDerivation rec {
     libusb1 libvorbis libebur128 pkgconfig portaudio portmidi protobuf qt5.full
     rubberband scons sqlite taglib soundtouch vamp.vampSDK opusfile upower hidapi
     ccache git glib x11 libGLU lilv lame lv2 makeWrapper qt5.qtbase
-  ];
+  ] ++ allLv2Plugins;
 
   sconsFlags = [
     "build=debug"
@@ -102,7 +110,7 @@ in stdenv.mkDerivation rec {
   installPhase = ''
     runHook preInstall
     scons $sconsFlags "prefix=$out" install
-    wrapProgram $out/bin/mixxx --suffix QT_PLUGIN_PATH : ${qt5.qtbase}/${qt5.qtbase.qtPluginPrefix} --set QTDIR ${qt5.full}
+    wrapProgram $out/bin/mixxx --suffix QT_PLUGIN_PATH : ${qt5.qtbase}/${qt5.qtbase.qtPluginPrefix} --set QTDIR ${qt5.full} --prefix LV2_PATH : ${lib.makeSearchPath "lib/lv2" allLv2Plugins}
     runHook postInstall
   '';
 
diff --git a/res/controllers/midi-components-0.0.js b/res/controllers/midi-components-0.0.js
index 4dc43be1e9..7bb5c00957 100644
--- a/res/controllers/midi-components-0.0.js
+++ b/res/controllers/midi-components-0.0.js
@@ -533,6 +533,34 @@
                 }
             }
         },
+        forEachComponentContainer: function (operation, recursive) {
+            if (typeof operation !== 'function') {
+                print('ERROR: ComponentContainer.forEachComponentContainer requires a function argument');
+                return;
+            }
+            if (recursive === undefined) { recursive = true; }
+
+            var that = this;
+            var applyOperationTo = function (obj) {
+                if (obj instanceof ComponentContainer) {
+                    operation.call(that, obj);
+
+                    if (recursive) {
+                        obj.forEachComponentContainer(operation);
+                    }
+                } else if (Array.isArray(obj)) {
+                    obj.forEach(function (element) {
+                        applyOperationTo(element);
+                    });
+                }
+            };
+
+            for (var memberName in this) {
+                if (this.hasOwnProperty(memberName)) {
+                    applyOperationTo(this[memberName]);
+                }
+            }
+        },
         reconnectComponents: function (operation, recursive) {
             this.forEachComponent(function (component) {
                 component.disconnect();
@@ -545,6 +573,7 @@
         },
         isShifted: false,
         shift: function () {
+            // Shift direct child Components
             this.forEachComponent(function (component) {
                 // Controls for push type Buttons depend on getting reset to 0 when the
                 // Button is released for correct behavior. If there is a skin button
@@ -568,11 +597,18 @@
                     }
                     component.shift();
                 }
-                // Set isShifted for child ComponentContainers forEachComponent is iterating through recursively
-                this.isShifted = true;
-            });
+            }, false);
+
+            // Shift child ComponentContainers
+            this.forEachComponentContainer(function (container) {
+                container.shift();
+            }, false);
+
+            // Set isShifted for each ComponentContainer recursively
+            this.isShifted = true;
         },
         unshift: function () {
+            // Unshift direct child Components
             this.forEachComponent(function (component) {
                 // Refer to comment in ComponentContainer.shift() above for explanation
                 if (typeof component.unshift === 'function') {
@@ -588,9 +624,15 @@
                     }
                     component.unshift();
                 }
-                // Set isShifted for child ComponentContainers forEachComponent is iterating through recursively
-                this.isShifted = false;
-            });
+            }, false);
+
+            // Unshift child ComponentContainers
+            this.forEachComponentContainer(function (container) {
+                container.unshift();
+            }, false);
+
+            // Unset isShifted for each ComponentContainer recursively
+            this.isShifted = false;
         },
         applyLayer: function (newLayer, reconnectComponents) {
             if (reconnectComponents !== false) {
diff --git a/src/engine/controls/loopingcontrol.cpp b/src/engine/controls/loopingcontrol.cpp
index 02f9e10fb4..245201df76 100644
--- a/src/engine/controls/loopingcontrol.cpp
+++ b/src/engine/controls/loopingcontrol.cpp
@@ -53,7 +53,7 @@ LoopingControl::LoopingControl(QString group,
     m_loopSamples.setValue(m_oldLoopSamples);
     m_currentSample.setValue(0.0);
     m_pActiveBeatLoop = NULL;
-
+    m_pRateControl = NULL;
     //Create loop-in, loop-out, loop-exit, and reloop/exit ControlObjects
     m_pLoopInButton = new ControlPushButton(ConfigKey(group, "loop_in"));
     connect(m_pLoopInButton, &ControlObject::valueChanged,
@@ -682,6 +682,10 @@ void LoopingControl::setLoopOutToCurrentPosition() {
     m_loopSamples.setValue(loopSamples);
 }
 
+void LoopingControl::setRateControl(RateControl* rateControl) {
+    m_pRateControl = rateControl;
+}
+
 void LoopingControl::slotLoopOut(double pressed) {
     if (m_pTrack == nullptr) {
         return;
@@ -1060,16 +1064,19 @@ void LoopingControl::slotBeatLoop(double beats, bool keepStartPoint, bool enable
             newloopSamples.start = currentSample;
         }
     } else {
-        // loop_in is set to the previous beat if quantize is on.  The
-        // closest beat might be ahead of play position which would cause a seek.
-        // TODO: If in reverse, should probably choose nextBeat.
+        // loop_in is set to the closest beat if quantize is on and the loop size is >= 1 beat.
+        // The closest beat might be ahead of play position and will cause a catching loop.
         double prevBeat;
         double nextBeat;
         pBeats->findPrevNextBeats(currentSample, &prevBeat, &nextBeat);
 
         if (m_pQuantizeEnabled->toBool() && prevBeat != -1) {
+            double beatLength = nextBeat - prevBeat;
+            double loopLength = beatLength * beats;
+
+            double closestBeat = pBeats->findClosestBeat(currentSample);
             if (beats >= 1.0) {
-                newloopSamples.start = prevBeat;
+                newloopSamples.start = closestBeat;
             } else {
                 // In case of beat length less then 1 beat:
                 // (| - beats, ^ - current track's position):
@@ -1078,15 +1085,29 @@ void LoopingControl::slotBeatLoop(double beats, bool keepStartPoint, bool enable
                 //
                 // If we press 1/2 beatloop we want loop from 50% to 100%,
                 // If I press 1/4 beatloop, we want loop from 50% to 75% etc
-                double beat_len = nextBeat - prevBeat;
-                double loops_per_beat = 1.0 / beats;
-                double beat_pos = currentSample - prevBeat;
-                int beat_frac =
-                        static_cast<int>(floor((beat_pos / beat_len) *
-                                                loops_per_beat));
-                newloopSamples.start = prevBeat + beat_len / loops_per_beat * beat_frac;
+                double samplesSinceLastBeat = currentSample - prevBeat;
+
+                // find the previous beat fraction and check if the current position is closer to this or the next one
+                // place the new loop start to the closer one
+                double previousFractionBeat = prevBeat + floor(samplesSinceLastBeat / loopLength) * loopLength;
+                double samplesSinceLastFractionBeat = currentSample - previousFractionBeat;
+
+                if (samplesSinceLastFractionBeat <= (loopLength / 2.0)) {
+                    newloopSamples.start = previousFractionBeat;
+                } else {
+                    newloopSamples.start = previousFractionBeat + loopLength;
+                }
             }
 
+            // If running reverse, move the loop one loop size to the left.
+            // Thus, the loops end will be closest to the current position
+            bool reverse = false;
+            if (m_pRateControl != NULL) {
+                reverse = m_pRateControl->isReverseButtonPressed();
+            }
+            if (reverse) {
+                newloopSamples.start -= loopLength;
+            }
         } else {
             newloopSamples.start = currentSample;
         }
diff --git a/src/engine/controls/loopingcontrol.h b/src/engine/controls/loopingcontrol.h
index 55d4f0c15f..6be5fdb78b 100644
--- a/src/engine/controls/loopingcontrol.h
+++ b/src/engine/controls/loopingcontrol.h
@@ -8,11 +8,12 @@
 #include <QObject>
 #include <QStack>
 
-#include "preferences/usersettings.h"
+#include "control/controlvalue.h"
 #include "engine/controls/enginecontrol.h"
-#include "track/track.h"
+#include "engine/controls/ratecontrol.h"
+#include "preferences/usersettings.h"
 #include "track/beats.h"
-#include "control/controlvalue.h"
+#include "track/track.h"
 
 #define MINIMUM_AUDIBLE_LOOP_SIZE   300  // In samples
 
@@ -50,7 +51,7 @@ class LoopingControl : public EngineControl {
     double getSyncPositionInsideLoop(double dRequestedPlaypos, double dSyncedPlayPos);
 
     void notifySeek(double dNewPlaypos) override;
-
+    void setRateControl(RateControl* rateControl);
     bool isLoopingEnabled();
 
   public slots:
@@ -129,6 +130,7 @@ class LoopingControl : public EngineControl {
     ControlPushButton* m_pLoopHalveButton;
     ControlPushButton* m_pLoopDoubleButton;
     ControlObject* m_pSlipEnabled;
+    RateControl* m_pRateControl;
     ControlObject* m_pPlayButton;
 
     bool m_bLoopingEnabled;
diff --git a/src/engine/controls/ratecontrol.cpp b/src/engine/controls/ratecontrol.cpp
index 75c7327b10..5ee5af58ff 100644
--- a/src/engine/controls/ratecontrol.cpp
+++ b/src/engine/controls/ratecontrol.cpp
@@ -556,3 +556,10 @@ void RateControl::resetRateTemp(void)
 void RateControl::notifySeek(double playPos) {
     m_pScratchController->notifySeek(playPos);
 }
+
+bool RateControl::isReverseButtonPressed() {
+    if (m_pReverseButton) {
+        return m_pReverseButton->toBool();
+    }
+    return false;
+}
diff --git a/src/engine/controls/ratecontrol.h b/src/engine/controls/ratecontrol.h
index 635ae15b2e..a53dfd383f 100644
--- a/src/engine/controls/ratecontrol.h
+++ b/src/engine/controls/ratecontrol.h
@@ -78,6 +78,7 @@ public:
     static void setRateRampSensitivity(int);
     static int getRateRampSensitivity();
     void notifySeek(double dNewPlaypos) override;
+    bool isReverseButtonPressed();
 
   public slots:
     void slotReverseRollActivate(double);
diff --git a/src/engine/enginebuffer.cpp b/src/engine/enginebuffer.cpp
index 2c10c3bfe8..5ba47c24a5 100644
--- a/src/engine/enginebuffer.cpp
+++ b/src/engine/enginebuffer.cpp
@@ -180,14 +180,13 @@ EngineBuffer::EngineBuffer(const QString& group, UserSettingsPointer pConfig,
     // quantization (alignment) of loop in/out positions and (hot)cues with
     // beats.
     QuantizeControl* quantize_control = new QuantizeControl(group, pConfig);
+    addControl(quantize_control);
+    m_pQuantize = ControlObject::getControl(ConfigKey(group, "quantize"));
 
     // Create the Loop Controller
     m_pLoopingControl = new LoopingControl(group, pConfig);
     addControl(m_pLoopingControl);
 
-    addControl(quantize_control);
-    m_pQuantize = ControlObject::getControl(ConfigKey(group, "quantize"));
-
     m_pEngineSync = pMixingEngine->getEngineSync();
 
     m_pSyncControl = new SyncControl(group, pConfig, pChannel, m_pEngineSync);
@@ -198,9 +197,12 @@ EngineBuffer::EngineBuffer(const QString& group, UserSettingsPointer pConfig,
     addControl(m_pVinylControlControl);
 #endif
 
+    // Create the Rate Controller
     m_pRateControl = new RateControl(group, pConfig);
     // Add the Rate Controller
     addControl(m_pRateControl);
+    // Looping Control needs Rate Control for Reverse Button
+    m_pLoopingControl->setRateControl(m_pRateControl);
 
     // Create the BPM Controller
     m_pBpmControl = new BpmControl(group, pConfig);
@@ -532,6 +534,10 @@ TrackPointer EngineBuffer::getLoadedTrack() const {
     return m_pCurrentTrack;
 }
 
+bool EngineBuffer::isReverse() {
+    return m_reverse_old;
+}
+
 void EngineBuffer::ejectTrack() {
     // clear track values in any case, this may fix Bug #1450424
     //qDebug() << "EngineBuffer::ejectTrack()";
diff --git a/src/engine/enginebuffer.h b/src/engine/enginebuffer.h
index 46735d16fa..394794225f 100644
--- a/src/engine/enginebuffer.h
+++ b/src/engine/enginebuffer.h
@@ -146,6 +146,8 @@ class EngineBuffer : public EngineObject {
     bool getQueuedSeekPosition(double* pSeekPosition);
     TrackPointer getLoadedTrack() const;
 
+    bool isReverse();
+
     double getExactPlayPos();
     double getVisualPlayPos();
     double getTrackSamples();
diff --git a/src/library/dao/directorydao.cpp b/src/library/dao/directorydao.cpp
index c490ef959d..15338680c7 100644
--- a/src/library/dao/directorydao.cpp
+++ b/src/library/dao/directorydao.cpp
@@ -14,7 +14,6 @@
 int DirectoryDAO::addDirectory(const QString& newDir) {
     // Do nothing if the dir to add is a child of a directory that is already in
     // the db.
-    ScopedTransaction transaction(m_database);
     QStringList dirs = getDirs();
     QString childDir;
     QString parentDir;
@@ -46,7 +45,6 @@ int DirectoryDAO::addDirectory(const QString& newDir) {
         LOG_FAILED_QUERY(query) << "Adding new dir (" % newDir % ") failed.";
         return SQL_ERROR;
     }
-    transaction.commit();
     return ALL_FINE;
 }
 
@@ -80,13 +78,12 @@ int DirectoryDAO::removeDirectory(const QString& dir) {
 }
 
 
-QSet<TrackId> DirectoryDAO::relocateDirectory(const QString& oldFolder,
+QList<TrackRef> DirectoryDAO::relocateDirectory(const QString& oldFolder,
                                           const QString& newFolder) {
     // TODO(rryan): This method could use error reporting. It can fail in
     // mysterious ways for example if a track in the oldFolder also has a zombie
     // track location in newFolder then the replace query will fail because the
     // location column becomes non-unique.
-    ScopedTransaction transaction(m_database);
     QSqlQuery query(m_database);
     query.prepare("UPDATE " % DIRECTORYDAO_TABLE % " SET " % DIRECTORYDAO_DIR %
                   "=:newFolder WHERE " % DIRECTORYDAO_DIR % " = :oldFolder");
@@ -95,7 +92,7 @@ QSet<TrackId> DirectoryDAO::relocateDirectory(const QString& oldFolder,
     if (!query.exec()) {
         LOG_FAILED_QUERY(query) << "could not relocate directory"
                                 << oldFolder << "to" << newFolder;
-        return QSet<TrackId>();
+        return {};
     }
 
     // on Windows the absolute path starts with the drive name
@@ -113,35 +110,32 @@ QSet<TrackId> DirectoryDAO::relocateDirectory(const QString& oldFolder,
                   .arg(startsWithOldFolder, kSqlLikeMatchAll));
     if (!query.exec()) {
         LOG_FAILED_QUERY(query) << "could not relocate path of tracks";
-        return QSet<TrackId>();
+        return {};
     }
 
-    QSet<TrackId> trackIds;
-    QList<int> loc_ids;
-    QStringList old_locs;
+    QList<DbId> loc_ids;
+    QList<TrackRef> trackRefs;
     while (query.next()) {
-        trackIds.insert(TrackId(query.value(0)));
-        loc_ids.append(query.value(1).toInt());
-        old_locs.append(query.value(2).toString());
+        loc_ids.append(DbId(query.value(1).toInt()));
+        trackRefs.append(TrackRef::fromFileInfo(query.value(2).toString(), TrackId(query.value(0))));
     }
 
     QString replacement = "UPDATE track_locations SET location = :newloc "
             "WHERE id = :id";
     query.prepare(replacement);
     for (int i = 0; i < loc_ids.size(); ++i) {
-        QString newloc = old_locs.at(i);
+        QString newloc = trackRefs.at(i).getLocation();
         newloc.replace(0, oldFolder.size(), newFolder);
         query.bindValue("newloc", newloc);
-        query.bindValue("id", loc_ids.at(i));
+        query.bindValue("id", loc_ids.at(i).toVariant());
         if (!query.exec()) {
             LOG_FAILED_QUERY(query) << "could not relocate path of tracks";
-            return QSet<TrackId>();
+            return {};
         }
     }
 
-    qDebug() << "Relocated tracks:" << trackIds.size();
-    transaction.commit();
-    return trackIds;
+    qDebug() << "Relocated tracks:" << trackRefs.size();
+    return trackRefs;
 }
 
 QStringList DirectoryDAO::getDirs() {
diff --git a/src/library/dao/directorydao.h b/src/library/dao/directorydao.h
index 827bd4a703..6892021a96 100644
--- a/src/library/dao/directorydao.h
+++ b/src/library/dao/directorydao.h
@@ -21,7 +21,7 @@ class DirectoryDAO : public DAO {