Expose cached waveform information to the user.

* Allow the user to disable waveform caching.
* Allow the user to clear cached waveforms on disk.
* Display cached waveform size on disk.
* Explain why cached waveforms are useful.

Partial fix for Bug #1023787.

src/library/dao/analysisdao.cpp

@@ -3,10 +3,11 @@
 #include <QSqlError>
 #include <QtDebug>
 
-#include "waveform/waveform.h"
 #include "library/dao/analysisdao.h"
 #include "library/queryutil.h"
+#include "preferences/waveformsettings.h"
 #include "util/performancetimer.h"
+#include "waveform/waveform.h"
 
 const QString AnalysisDao::s_analysisTableName = "track_analysis";
 
@@ -83,6 +84,7 @@ QList<AnalysisDao::AnalysisInfo> AnalysisDao::loadAnalysesFromQuery(TrackId trac
     const int versionColumn = queryRecord.indexOf("version");
     const int dataChecksumColumn = queryRecord.indexOf("data_checksum");
 
+    QDir analysisPath(getAnalysisStoragePath());
     while (query->next()) {
         AnalysisDao::AnalysisInfo info;
         info.analysisId = query->value(idColumn).toInt();
@@ -91,7 +93,7 @@ QList<AnalysisDao::AnalysisInfo> AnalysisDao::loadAnalysesFromQuery(TrackId trac
         info.description = query->value(descriptionColumn).toString();
         info.version = query->value(versionColumn).toString();
         int checksum = query->value(dataChecksumColumn).toInt();
-        QString dataPath = getAnalysisStoragePath().absoluteFilePath(
+        QString dataPath = analysisPath.absoluteFilePath(
             QString::number(info.analysisId));
         QByteArray compressedData = loadDataFromFile(dataPath);
         int file_checksum = qChecksum(compressedData.constData(),
@@ -216,11 +218,10 @@ void AnalysisDao::deleteAnalyses(const QList<TrackId>& trackIds) {
         LOG_FAILED_QUERY(query) << "couldn't delete analysis";
     }
     const int idColumn = query.record().indexOf("id");
+    QDir analysisPath(getAnalysisStoragePath());
     while (query.next()) {
         int id = query.value(idColumn).toInt();
-        QString dataPath = getAnalysisStoragePath().absoluteFilePath(
-                            QString::number(id));
-        qDebug() << dataPath;
+        QString dataPath = analysisPath.absoluteFilePath(QString::number(id));
         deleteFile(dataPath);
     }
     query.prepare(QString("DELETE FROM track_analysis "
@@ -320,6 +321,13 @@ void AnalysisDao::saveTrackAnalyses(Track* pTrack) {
         return;
     }
 
+    // The only analyses we have at the moment are waveform analyses so we have
+    // nothing to do if it is disabled.
+    WaveformSettings waveformSettings(m_pConfig);
+    if (!waveformSettings.waveformCachingEnabled()) {
+        return;
+    }
+
     ConstWaveformPointer pWaveform = pTrack->getWaveform();
     ConstWaveformPointer pWaveSummary = pTrack->getWaveformSummary();
 
@@ -364,3 +372,44 @@ void AnalysisDao::saveTrackAnalyses(Track* pTrack) {
              << "waveform summary analysis for trackId" << trackId
              << "analysisId" << analysis.analysisId;
 }
+
+size_t AnalysisDao::getDiskUsageInBytes(AnalysisType type) {
+    QDir analysisPath(getAnalysisStoragePath());
+
+    QSqlQuery query(m_db);
+    query.prepare(QString("SELECT id FROM %1 WHERE type=:type").arg(s_analysisTableName));
+    query.bindValue(":type", type);
+
+    if (!query.exec()) {
+        LOG_FAILED_QUERY(query) << "couldn't get analyses of type" << type;
+        return 0;
+    }
+
+    const int idColumn = query.record().indexOf("id");
+    size_t total = 0;
+    while (query.next()) {
+        total += QFileInfo(analysisPath.absoluteFilePath(
+                query.value(idColumn).toString())).size();
+    }
+    return total;
+}
+
+bool AnalysisDao::deleteAnalysesByType(AnalysisType type) {
+    QDir analysisPath(getAnalysisStoragePath());
+
+    QSqlQuery query(m_db);
+    query.prepare(QString("SELECT id FROM %1 WHERE type=:type").arg(s_analysisTableName));
+    query.bindValue(":type", type);
+
+    if (!query.exec()) {
+        LOG_FAILED_QUERY(query) << "couldn't get analyses of type" << type;
+        return false;
+    }
+
+    const int idColumn = query.record().indexOf("id");
+    while (query.next()) {
+        QString dataPath = analysisPath.absoluteFilePath(query.value(idColumn).toString());
+        deleteFile(dataPath);
+    }
+    return true;
+}

src/library/dao/analysisdao.h

@@ -47,9 +47,12 @@ class AnalysisDao : public DAO {
     bool deleteAnalysis(const int analysisId);
     void deleteAnalyses(const QList<TrackId>& trackIds);
     bool deleteAnalysesForTrack(TrackId trackId);
+    bool deleteAnalysesByType(AnalysisType type);
 
     void saveTrackAnalyses(Track* pTrack);
 
+    size_t getDiskUsageInBytes(AnalysisType type);
+
   private:
     bool saveWaveform(const Track& tio,
                       const Waveform& waveform,

src/library/trackcollection.h

@@ -63,6 +63,9 @@ class TrackCollection : public QObject {
     TrackDAO& getTrackDAO();
     PlaylistDAO& getPlaylistDAO();
     DirectoryDAO& getDirectoryDAO();
+    AnalysisDao& getAnalysisDAO() {
+        return m_analysisDao;
+    }
     QSharedPointer<BaseTrackCache> getTrackSource();
     void setTrackSource(QSharedPointer<BaseTrackCache> trackSource);
     void cancelLibraryScan();

src/preferences/dialog/dlgpreferences.cpp

@@ -100,7 +100,7 @@ DlgPreferences::DlgPreferences(MixxxMainWindow * mixxx, SkinLoader* pSkinLoader,
             pLibrary, SLOT(scan()));
     m_wcontrols = new DlgPrefControls(this, mixxx, pSkinLoader, pPlayerManager, m_pConfig);
     addPageWidget(m_wcontrols);
-    m_wwaveform = new DlgPrefWaveform(this, mixxx, m_pConfig);
+    m_wwaveform = new DlgPrefWaveform(this, mixxx, m_pConfig, pLibrary);
     addPageWidget(m_wwaveform);
     m_wautodj = new DlgPrefAutoDJ(this, m_pConfig);
     addPageWidget(m_wautodj);

src/preferences/dialog/dlgprefwaveform.cpp

@@ -1,13 +1,15 @@
 #include "preferences/dialog/dlgprefwaveform.h"
 
 #include "mixxx.h"
+#include "preferences/waveformsettings.h"
 #include "waveform/waveformwidgetfactory.h"
 #include "waveform/renderers/waveformwidgetrenderer.h"
 
 DlgPrefWaveform::DlgPrefWaveform(QWidget* pParent, MixxxMainWindow* pMixxx,
-                                 UserSettingsPointer pConfig)
+                                 UserSettingsPointer pConfig, Library* pLibrary)
         : DlgPreferencePage(pParent),
           m_pConfig(pConfig),
+          m_pLibrary(pLibrary),
           m_pMixxx(pMixxx) {
     setupUi(this);
 
@@ -53,20 +55,22 @@ DlgPrefWaveform::DlgPrefWaveform(QWidget* pParent, MixxxMainWindow* pMixxx,
             this, SLOT(slotSetDefaultZoom(int)));
     connect(synchronizeZoomCheckBox, SIGNAL(clicked(bool)),
             this, SLOT(slotSetZoomSynchronization(bool)));
-    connect(allVisualGain,SIGNAL(valueChanged(double)),
-            this,SLOT(slotSetVisualGainAll(double)));
-    connect(lowVisualGain,SIGNAL(valueChanged(double)),
-            this,SLOT(slotSetVisualGainLow(double)));
-    connect(midVisualGain,SIGNAL(valueChanged(double)),
-            this,SLOT(slotSetVisualGainMid(double)));
-    connect(highVisualGain,SIGNAL(valueChanged(double)),
-            this,SLOT(slotSetVisualGainHigh(double)));
-    connect(normalizeOverviewCheckBox,SIGNAL(toggled(bool)),
-            this,SLOT(slotSetNormalizeOverview(bool)));
+    connect(allVisualGain, SIGNAL(valueChanged(double)),
+            this, SLOT(slotSetVisualGainAll(double)));
+    connect(lowVisualGain, SIGNAL(valueChanged(double)),
+            this, SLOT(slotSetVisualGainLow(double)));
+    connect(midVisualGain, SIGNAL(valueChanged(double)),
+            this, SLOT(slotSetVisualGainMid(double)));
+    connect(highVisualGain, SIGNAL(valueChanged(double)),
+            this, SLOT(slotSetVisualGainHigh(double)));
+    connect(normalizeOverviewCheckBox, SIGNAL(toggled(bool)),
+            this, SLOT(slotSetNormalizeOverview(bool)));
     connect(factory, SIGNAL(waveformMeasured(float,int)),
             this, SLOT(slotWaveformMeasured(float,int)));
-    connect(waveformOverviewComboBox,SIGNAL(currentIndexChanged(int)),
-            this,SLOT(slotSetWaveformOverviewType(int)));
+    connect(waveformOverviewComboBox, SIGNAL(currentIndexChanged(int)),
+            this, SLOT(slotSetWaveformOverviewType(int)));
+    connect(clearCachedWaveforms, SIGNAL(clicked()),
+            this, SLOT(slotClearCachedWaveforms()));
 }
 
 DlgPrefWaveform::~DlgPrefWaveform() {
@@ -105,9 +109,15 @@ void DlgPrefWaveform::slotUpdate() {
     if (overviewType != waveformOverviewComboBox->currentIndex()) {
         waveformOverviewComboBox->setCurrentIndex(overviewType);
     }
+
+    WaveformSettings waveformSettings(m_pConfig);
+    enableWaveformCaching->setChecked(waveformSettings.waveformCachingEnabled());
+    calculateCachedWaveformDiskUsage();
 }
 
 void DlgPrefWaveform::slotApply() {
+    WaveformSettings waveformSettings(m_pConfig);
+    waveformSettings.setWaveformCachingEnabled(enableWaveformCaching->isChecked());
 }
 
 void DlgPrefWaveform::slotResetToDefaults() {
@@ -141,14 +151,19 @@ void DlgPrefWaveform::slotResetToDefaults() {
     // 30FPS is the default
     frameRateSlider->setValue(30);
     endOfTrackWarningTimeSlider->setValue(30);
+
+    // Waveform caching enabled.
+    enableWaveformCaching->setChecked(true);
 }
 
 void DlgPrefWaveform::slotSetFrameRate(int frameRate) {
     WaveformWidgetFactory::instance()->setFrameRate(frameRate);
 }
+
 void DlgPrefWaveform::slotSetWaveformEndRender(int endTime) {
     WaveformWidgetFactory::instance()->setEndOfTrackWarningTime(endTime);
 }
+
 void DlgPrefWaveform::slotSetWaveformType(int index) {
     // Ignore sets for -1 since this happens when we clear the combobox.
     if (index < 0) {
@@ -195,3 +210,29 @@ void DlgPrefWaveform::slotWaveformMeasured(float frameRate, int droppedFrames) {
             QString::number((double)frameRate, 'f', 2) + " : " +
             tr("dropped frames") + " " + QString::number(droppedFrames));
 }
+
+void DlgPrefWaveform::slotClearCachedWaveforms() {
+    TrackCollection* pTrackCollection = m_pLibrary->getTrackCollection();
+    if (pTrackCollection != nullptr) {
+        AnalysisDao& analysisDao = pTrackCollection->getAnalysisDAO();
+        analysisDao.deleteAnalysesByType(AnalysisDao::TYPE_WAVEFORM);
+        analysisDao.deleteAnalysesByType(AnalysisDao::TYPE_WAVESUMMARY);
+        calculateCachedWaveformDiskUsage();
+    }
+}
+
+void DlgPrefWaveform::calculateCachedWaveformDiskUsage() {
+    TrackCollection* pTrackCollection = m_pLibrary->getTrackCollection();
+    if (pTrackCollection != nullptr) {
+        AnalysisDao& analysisDao = pTrackCollection->getAnalysisDAO();
+        size_t waveformBytes = analysisDao.getDiskUsageInBytes(AnalysisDao::TYPE_WAVEFORM);
+        size_t wavesummaryBytes = analysisDao.getDiskUsageInBytes(AnalysisDao::TYPE_WAVESUMMARY);
+
+        // Display total cached waveform size in mebibytes with 2 decimals.
+        QString sizeMebibytes = QString::number(
+                (waveformBytes + wavesummaryBytes) / (1024.0 * 1024.0), 'f', 2);
+
+        waveformDiskUsage->setText(
+                tr("Cached waveforms occupy %1 MiB on disk.").arg(sizeMebibytes));
+    }
+}

src/preferences/dialog/dlgprefwaveform.h

@@ -3,6 +3,7 @@
 
 #include <QWidget>
 
+#include "library/library.h"
 #include "preferences/dialog/ui_dlgprefwaveformdlg.h"
 #include "preferences/usersettings.h"
 #include "preferences/dlgpreferencepage.h"
@@ -13,7 +14,7 @@ class DlgPrefWaveform : public DlgPreferencePage, public Ui::DlgPrefWaveformDlg
     Q_OBJECT
   public:
     DlgPrefWaveform(QWidget* pParent, MixxxMainWindow* pMixxx,
-                    UserSettingsPointer pConfig);
+                    UserSettingsPointer pConfig, Library* pLibrary);
     virtual ~DlgPrefWaveform();
 
   public slots:
@@ -34,11 +35,14 @@ class DlgPrefWaveform : public DlgPreferencePage, public Ui::DlgPrefWaveformDlg
     void slotSetVisualGainHigh(double gain);
     void slotSetNormalizeOverview(bool normalize);
     void slotWaveformMeasured(float frameRate, int droppedFrames);
+    void slotClearCachedWaveforms();
 
   private:
     void initWaveformControl();
+    void calculateCachedWaveformDiskUsage();
 
     UserSettingsPointer m_pConfig;
+    Library* m_pLibrary;
     MixxxMainWindow* m_pMixxx;
 };