annotate framework/MainWindowBase.cpp @ 77:0535c49069ba

* Various fixes to object lifetime management, particularly in the spectrum
  layer and for notification of main model deletion.
  The main purpose of this is to improve the behaviour of the spectrum, but I
  think it may also help with #1840922 Various crashes in Layer Summary window.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006-2007 Chris Cannam and QMUL.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#include "MainWindowBase.h"
#include "Document.h"


#include "view/Pane.h"
#include "view/PaneStack.h"
#include "data/model/WaveFileModel.h"
#include "data/model/SparseOneDimensionalModel.h"
#include "data/model/NoteModel.h"
#include "data/model/Labeller.h"
#include "view/ViewManager.h"

#include "layer/WaveformLayer.h"
#include "layer/TimeRulerLayer.h"
#include "layer/TimeInstantLayer.h"
#include "layer/TimeValueLayer.h"
#include "layer/Colour3DPlotLayer.h"
#include "layer/SliceLayer.h"
#include "layer/SliceableLayer.h"
#include "layer/ImageLayer.h"

#include "widgets/ListInputDialog.h"

#include "audioio/AudioCallbackPlaySource.h"
#include "audioio/AudioCallbackPlayTarget.h"
#include "audioio/AudioTargetFactory.h"
#include "audioio/PlaySpeedRangeMapper.h"
#include "data/fileio/DataFileReaderFactory.h"
#include "data/fileio/PlaylistFileReader.h"
#include "data/fileio/WavFileWriter.h"
#include "data/fileio/CSVFileWriter.h"
#include "data/fileio/MIDIFileWriter.h"
#include "data/fileio/BZipFileDevice.h"
#include "data/fileio/FileSource.h"

#include "data/fft/FFTDataServer.h"

#include "base/RecentFiles.h"

#include "base/PlayParameterRepository.h"
#include "base/XmlExportable.h"
#include "base/CommandHistory.h"
#include "base/Profiler.h"
#include "base/Preferences.h"

#include "data/osc/OSCQueue.h"

#include <QApplication>
#include <QMessageBox>
#include <QGridLayout>
#include <QLabel>
#include <QAction>
#include <QMenuBar>
#include <QToolBar>
#include <QInputDialog>
#include <QStatusBar>
#include <QTreeView>
#include <QFile>
#include <QFileInfo>
#include <QDir>
#include <QTextStream>
#include <QProcess>
#include <QShortcut>
#include <QSettings>
#include <QDateTime>
#include <QProcess>
#include <QCheckBox>
#include <QRegExp>
#include <QScrollArea>

#include <iostream>
#include <cstdio>
#include <errno.h>

using std::cerr;
using std::endl;

using std::vector;
using std::map;
using std::set;


MainWindowBase::MainWindowBase(bool withAudioOutput, bool withOSCSupport) :
    m_document(0),
    m_paneStack(0),
    m_viewManager(0),
    m_timeRulerLayer(0),
    m_audioOutput(withAudioOutput),
    m_playSource(0),
    m_playTarget(0),
    m_oscQueue(withOSCSupport ? new OSCQueue() : 0),
    m_recentFiles("RecentFiles", 20),
    m_recentTransforms("RecentTransforms", 20),
    m_documentModified(false),
    m_openingAudioFile(false),
    m_abandoning(false),
    m_labeller(0)
{
    connect(CommandHistory::getInstance(), SIGNAL(commandExecuted()),
	    this, SLOT(documentModified()));
    connect(CommandHistory::getInstance(), SIGNAL(documentRestored()),
	    this, SLOT(documentRestored()));
    
    m_viewManager = new ViewManager();
    connect(m_viewManager, SIGNAL(selectionChanged()),
	    this, SLOT(updateMenuStates()));
    connect(m_viewManager, SIGNAL(inProgressSelectionChanged()),
	    this, SLOT(inProgressSelectionChanged()));

    Preferences::BackgroundMode mode =
        Preferences::getInstance()->getBackgroundMode();
    m_initialDarkBackground = m_viewManager->getGlobalDarkBackground();
    if (mode != Preferences::BackgroundFromTheme) {
        m_viewManager->setGlobalDarkBackground
            (mode == Preferences::DarkBackground);
    }

    m_paneStack = new PaneStack(0, m_viewManager);
    connect(m_paneStack, SIGNAL(currentPaneChanged(Pane *)),
	    this, SLOT(currentPaneChanged(Pane *)));
    connect(m_paneStack, SIGNAL(currentLayerChanged(Pane *, Layer *)),
	    this, SLOT(currentLayerChanged(Pane *, Layer *)));
    connect(m_paneStack, SIGNAL(rightButtonMenuRequested(Pane *, QPoint)),
            this, SLOT(rightButtonMenuRequested(Pane *, QPoint)));
    connect(m_paneStack, SIGNAL(contextHelpChanged(const QString &)),
            this, SLOT(contextHelpChanged(const QString &)));
    connect(m_paneStack, SIGNAL(paneAdded(Pane *)),
            this, SLOT(paneAdded(Pane *)));
    connect(m_paneStack, SIGNAL(paneHidden(Pane *)),
            this, SLOT(paneHidden(Pane *)));
    connect(m_paneStack, SIGNAL(paneAboutToBeDeleted(Pane *)),
            this, SLOT(paneAboutToBeDeleted(Pane *)));
    connect(m_paneStack, SIGNAL(dropAccepted(Pane *, QStringList)),
            this, SLOT(paneDropAccepted(Pane *, QStringList)));
    connect(m_paneStack, SIGNAL(dropAccepted(Pane *, QString)),
            this, SLOT(paneDropAccepted(Pane *, QString)));
    connect(m_paneStack, SIGNAL(paneDeleteButtonClicked(Pane *)),
            this, SLOT(paneDeleteButtonClicked(Pane *)));

    m_playSource = new AudioCallbackPlaySource(m_viewManager,
                                               QApplication::applicationName());

    connect(m_playSource, SIGNAL(sampleRateMismatch(size_t, size_t, bool)),
	    this,           SLOT(sampleRateMismatch(size_t, size_t, bool)));
    connect(m_playSource, SIGNAL(audioOverloadPluginDisabled()),
            this,           SLOT(audioOverloadPluginDisabled()));

    connect(m_viewManager, SIGNAL(outputLevelsChanged(float, float)),
	    this, SLOT(outputLevelsChanged(float, float)));

    connect(m_viewManager, SIGNAL(playbackFrameChanged(unsigned long)),
            this, SLOT(playbackFrameChanged(unsigned long)));

    connect(m_viewManager, SIGNAL(globalCentreFrameChanged(unsigned long)),
            this, SLOT(globalCentreFrameChanged(unsigned long)));

    connect(m_viewManager, SIGNAL(viewCentreFrameChanged(View *, unsigned long)),
            this, SLOT(viewCentreFrameChanged(View *, unsigned long)));

    connect(m_viewManager, SIGNAL(viewZoomLevelChanged(View *, unsigned long, bool)),
            this, SLOT(viewZoomLevelChanged(View *, unsigned long, bool)));

    connect(Preferences::getInstance(),
            SIGNAL(propertyChanged(PropertyContainer::PropertyName)),
            this,
            SLOT(preferenceChanged(PropertyContainer::PropertyName)));

    if (m_oscQueue && m_oscQueue->isOK()) {
        connect(m_oscQueue, SIGNAL(messagesAvailable()), this, SLOT(pollOSC()));
        QTimer *oscTimer = new QTimer(this);
        connect(oscTimer, SIGNAL(timeout()), this, SLOT(pollOSC()));
        oscTimer->start(1000);
    }

    Labeller::ValueType labellerType = Labeller::ValueFromTwoLevelCounter;
    QSettings settings;
    settings.beginGroup("MainWindow");
    labellerType = (Labeller::ValueType)
        settings.value("labellertype", (int)labellerType).toInt();
    int cycle = settings.value("labellercycle", 4).toInt();
    settings.endGroup();

    m_labeller = new Labeller(labellerType);
    m_labeller->setCounterCycleSize(cycle);
}

MainWindowBase::~MainWindowBase()
{
    if (m_playTarget) m_playTarget->shutdown();
//    delete m_playTarget;
    delete m_playSource;
    delete m_viewManager;
    delete m_oscQueue;
    Profiles::getInstance()->dump();
}

QString
MainWindowBase::getOpenFileName(FileFinder::FileType type)
{
    FileFinder *ff = FileFinder::getInstance();
    switch (type) {
    case FileFinder::SessionFile:
        return ff->getOpenFileName(type, m_sessionFile);
    case FileFinder::AudioFile:
        return ff->getOpenFileName(type, m_audioFile);
    case FileFinder::LayerFile:
        return ff->getOpenFileName(type, m_sessionFile);
    case FileFinder::LayerFileNoMidi:
        return ff->getOpenFileName(type, m_sessionFile);
    case FileFinder::SessionOrAudioFile:
        return ff->getOpenFileName(type, m_sessionFile);
    case FileFinder::ImageFile:
        return ff->getOpenFileName(type, m_sessionFile);
    case FileFinder::AnyFile:
        if (getMainModel() != 0 &&
            m_paneStack != 0 &&
            m_paneStack->getCurrentPane() != 0) { // can import a layer
            return ff->getOpenFileName(FileFinder::AnyFile, m_sessionFile);
        } else {
            return ff->getOpenFileName(FileFinder::SessionOrAudioFile,
                                       m_sessionFile);
        }
    }
    return "";
}

QString
MainWindowBase::getSaveFileName(FileFinder::FileType type)
{
    FileFinder *ff = FileFinder::getInstance();
    switch (type) {
    case FileFinder::SessionFile:
        return ff->getSaveFileName(type, m_sessionFile);
    case FileFinder::AudioFile:
        return ff->getSaveFileName(type, m_audioFile);
    case FileFinder::LayerFile:
        return ff->getSaveFileName(type, m_sessionFile);
    case FileFinder::LayerFileNoMidi:
        return ff->getSaveFileName(type, m_sessionFile);
    case FileFinder::SessionOrAudioFile:
        return ff->getSaveFileName(type, m_sessionFile);
    case FileFinder::ImageFile:
        return ff->getSaveFileName(type, m_sessionFile);
    case FileFinder::AnyFile:
        return ff->getSaveFileName(type, m_sessionFile);
    }
    return "";
}

void
MainWindowBase::registerLastOpenedFilePath(FileFinder::FileType type, QString path)
{
    FileFinder *ff = FileFinder::getInstance();
    ff->registerLastOpenedFilePath(type, path);
}

void
MainWindowBase::updateMenuStates()
{
    Pane *currentPane = 0;
    Layer *currentLayer = 0;

    if (m_paneStack) currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentLayer = currentPane->getSelectedLayer();

    bool havePrevPane = false, haveNextPane = false;
    bool havePrevLayer = false, haveNextLayer = false;

    if (currentPane) {
        for (int i = 0; i < m_paneStack->getPaneCount(); ++i) {
            if (m_paneStack->getPane(i) == currentPane) {
                if (i > 0) havePrevPane = true;
                if (i < m_paneStack->getPaneCount()-1) haveNextPane = true;
                break;
            }
        }
        if (currentLayer) {
            for (int i = 0; i < currentPane->getLayerCount(); ++i) {
                if (currentPane->getLayer(i) == currentLayer) {
                    if (i > 0) havePrevLayer = true;
                    if (i < currentPane->getLayerCount()-1) haveNextLayer = true;
                    break;
                }
            }
        }
    }        

    bool haveCurrentPane =
        (currentPane != 0);
    bool haveCurrentLayer =
        (haveCurrentPane &&
         (currentLayer != 0));
    bool haveMainModel =
	(getMainModel() != 0);
    bool havePlayTarget =
	(m_playTarget != 0);
    bool haveSelection = 
	(m_viewManager &&
	 !m_viewManager->getSelections().empty());
    bool haveCurrentEditableLayer =
	(haveCurrentLayer &&
	 currentLayer->isLayerEditable());
    bool haveCurrentTimeInstantsLayer = 
	(haveCurrentLayer &&
	 dynamic_cast<TimeInstantLayer *>(currentLayer));
    bool haveCurrentColour3DPlot =
        (haveCurrentLayer &&
         dynamic_cast<Colour3DPlotLayer *>(currentLayer));
    bool haveClipboardContents =
        (m_viewManager &&
         !m_viewManager->getClipboard().empty());

    emit canAddPane(haveMainModel);
    emit canDeleteCurrentPane(haveCurrentPane);
    emit canZoom(haveMainModel && haveCurrentPane);
    emit canScroll(haveMainModel && haveCurrentPane);
    emit canAddLayer(haveMainModel && haveCurrentPane);
    emit canImportMoreAudio(haveMainModel);
    emit canImportLayer(haveMainModel && haveCurrentPane);
    emit canExportAudio(haveMainModel);
    emit canExportLayer(haveMainModel &&
                        (haveCurrentEditableLayer || haveCurrentColour3DPlot));
    emit canExportImage(haveMainModel && haveCurrentPane);
    emit canDeleteCurrentLayer(haveCurrentLayer);
    emit canRenameLayer(haveCurrentLayer);
    emit canEditLayer(haveCurrentEditableLayer);
    emit canMeasureLayer(haveCurrentLayer);
    emit canSelect(haveMainModel && haveCurrentPane);
    emit canPlay(havePlayTarget);
    emit canFfwd(true);
    emit canRewind(true);
    emit canPaste(haveCurrentEditableLayer && haveClipboardContents);
    emit canInsertInstant(haveCurrentPane);
    emit canInsertInstantsAtBoundaries(haveCurrentPane && haveSelection);
    emit canRenumberInstants(haveCurrentTimeInstantsLayer && haveSelection);
    emit canPlaySelection(haveMainModel && havePlayTarget && haveSelection);
    emit canClearSelection(haveSelection);
    emit canEditSelection(haveSelection && haveCurrentEditableLayer);
    emit canSave(m_sessionFile != "" && m_documentModified);
    emit canSelectPreviousPane(havePrevPane);
    emit canSelectNextPane(haveNextPane);
    emit canSelectPreviousLayer(havePrevLayer);
    emit canSelectNextLayer(haveNextLayer);
}

void
MainWindowBase::documentModified()
{
//    std::cerr << "MainWindowBase::documentModified" << std::endl;

    if (!m_documentModified) {
        //!!! this in subclass implementation?
	setWindowTitle(tr("%1 (modified)").arg(windowTitle()));
    }

    m_documentModified = true;
    updateMenuStates();
}

void
MainWindowBase::documentRestored()
{
//    std::cerr << "MainWindowBase::documentRestored" << std::endl;

    if (m_documentModified) {
        //!!! this in subclass implementation?
	QString wt(windowTitle());
	wt.replace(tr(" (modified)"), "");
	setWindowTitle(wt);
    }

    m_documentModified = false;
    updateMenuStates();
}

void
MainWindowBase::playLoopToggled()
{
    QAction *action = dynamic_cast<QAction *>(sender());
    
    if (action) {
	m_viewManager->setPlayLoopMode(action->isChecked());
    } else {
	m_viewManager->setPlayLoopMode(!m_viewManager->getPlayLoopMode());
    }
}

void
MainWindowBase::playSelectionToggled()
{
    QAction *action = dynamic_cast<QAction *>(sender());
    
    if (action) {
	m_viewManager->setPlaySelectionMode(action->isChecked());
    } else {
	m_viewManager->setPlaySelectionMode(!m_viewManager->getPlaySelectionMode());
    }
}

void
MainWindowBase::playSoloToggled()
{
    QAction *action = dynamic_cast<QAction *>(sender());
    
    if (action) {
	m_viewManager->setPlaySoloMode(action->isChecked());
    } else {
	m_viewManager->setPlaySoloMode(!m_viewManager->getPlaySoloMode());
    }

    if (m_viewManager->getPlaySoloMode()) {
        currentPaneChanged(m_paneStack->getCurrentPane());
    } else {
        m_viewManager->setPlaybackModel(0);
        if (m_playSource) {
            m_playSource->clearSoloModelSet();
        }
    }
}

void
MainWindowBase::currentPaneChanged(Pane *p)
{
    updateMenuStates();
    updateVisibleRangeDisplay(p);

    if (!p) return;

    if (!(m_viewManager &&
          m_playSource &&
          m_viewManager->getPlaySoloMode())) {
        if (m_viewManager) m_viewManager->setPlaybackModel(0);
        return;
    }

    Model *prevPlaybackModel = m_viewManager->getPlaybackModel();
    int frame = m_playSource->getCurrentPlayingFrame();

    std::cerr << "playing frame (in ref model) = " << frame << std::endl;

    View::ModelSet soloModels = p->getModels();
    
    View::ModelSet sources;
    for (View::ModelSet::iterator mi = soloModels.begin();
         mi != soloModels.end(); ++mi) {
        if (*mi && (*mi)->getSourceModel()) {
            sources.insert((*mi)->getSourceModel());
        }
    }
    for (View::ModelSet::iterator mi = sources.begin();
         mi != sources.end(); ++mi) {
        soloModels.insert(*mi);
    }

    //!!! Need an "atomic" way of telling the play source that the
    //playback model has changed, and changing it on ViewManager --
    //the play source should be making the setPlaybackModel call to
    //ViewManager

    for (View::ModelSet::iterator mi = soloModels.begin();
         mi != soloModels.end(); ++mi) {
        if (dynamic_cast<RangeSummarisableTimeValueModel *>(*mi)) {
            m_viewManager->setPlaybackModel(*mi);
        }
    }
    
    RangeSummarisableTimeValueModel *a = 
        dynamic_cast<RangeSummarisableTimeValueModel *>(prevPlaybackModel);
    RangeSummarisableTimeValueModel *b = 
        dynamic_cast<RangeSummarisableTimeValueModel *>(m_viewManager->
                                                        getPlaybackModel());

    m_playSource->setSoloModelSet(soloModels);

    if (a && b && (a != b)) {
/*!!!
        int rframe = a->alignToReference(frame);
        int bframe = b->alignFromReference(rframe);
        if (m_playSource->isPlaying()) m_playSource->play(bframe);
*/
        if (m_playSource->isPlaying()) m_playSource->play(frame);
    }
}

void
MainWindowBase::currentLayerChanged(Pane *p, Layer *)
{
    updateMenuStates();
    updateVisibleRangeDisplay(p);
}

void
MainWindowBase::selectAll()
{
    if (!getMainModel()) return;
    m_viewManager->setSelection(Selection(getMainModel()->getStartFrame(),
					  getMainModel()->getEndFrame()));
}

void
MainWindowBase::selectToStart()
{
    if (!getMainModel()) return;
    m_viewManager->setSelection(Selection(getMainModel()->getStartFrame(),
					  m_viewManager->getGlobalCentreFrame()));
}

void
MainWindowBase::selectToEnd()
{
    if (!getMainModel()) return;
    m_viewManager->setSelection(Selection(m_viewManager->getGlobalCentreFrame(),
					  getMainModel()->getEndFrame()));
}

void
MainWindowBase::selectVisible()
{
    Model *model = getMainModel();
    if (!model) return;

    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    size_t startFrame, endFrame;

    if (currentPane->getStartFrame() < 0) startFrame = 0;
    else startFrame = currentPane->getStartFrame();

    if (currentPane->getEndFrame() > model->getEndFrame()) endFrame = model->getEndFrame();
    else endFrame = currentPane->getEndFrame();

    m_viewManager->setSelection(Selection(startFrame, endFrame));
}

void
MainWindowBase::clearSelection()
{
    m_viewManager->clearSelections();
}

void
MainWindowBase::cut()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    Layer *layer = currentPane->getSelectedLayer();
    if (!layer) return;

    Clipboard &clipboard = m_viewManager->getClipboard();
    clipboard.clear();

    MultiSelection::SelectionList selections = m_viewManager->getSelections();

    CommandHistory::getInstance()->startCompoundOperation(tr("Cut"), true);

    for (MultiSelection::SelectionList::iterator i = selections.begin();
         i != selections.end(); ++i) {
        layer->copy(*i, clipboard);
        layer->deleteSelection(*i);
    }

    CommandHistory::getInstance()->endCompoundOperation();
}

void
MainWindowBase::copy()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    Layer *layer = currentPane->getSelectedLayer();
    if (!layer) return;

    Clipboard &clipboard = m_viewManager->getClipboard();
    clipboard.clear();

    MultiSelection::SelectionList selections = m_viewManager->getSelections();

    for (MultiSelection::SelectionList::iterator i = selections.begin();
         i != selections.end(); ++i) {
        layer->copy(*i, clipboard);
    }
}

void
MainWindowBase::paste()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    //!!! if we have no current layer, we should create one of the most
    // appropriate type

    Layer *layer = currentPane->getSelectedLayer();
    if (!layer) return;

    Clipboard &clipboard = m_viewManager->getClipboard();
    Clipboard::PointList contents = clipboard.getPoints();
/*
    long minFrame = 0;
    bool have = false;
    for (int i = 0; i < contents.size(); ++i) {
        if (!contents[i].haveFrame()) continue;
        if (!have || contents[i].getFrame() < minFrame) {
            minFrame = contents[i].getFrame();
            have = true;
        }
    }

    long frameOffset = long(m_viewManager->getGlobalCentreFrame()) - minFrame;

    layer->paste(clipboard, frameOffset);
*/
    layer->paste(clipboard, 0, true);
}

void
MainWindowBase::deleteSelected()
{
    if (m_paneStack->getCurrentPane() &&
	m_paneStack->getCurrentPane()->getSelectedLayer()) {
        
        Layer *layer = m_paneStack->getCurrentPane()->getSelectedLayer();

        if (m_viewManager && 
            (m_viewManager->getToolMode() == ViewManager::MeasureMode)) {

            layer->deleteCurrentMeasureRect();

        } else {

            MultiSelection::SelectionList selections =
                m_viewManager->getSelections();
            
            for (MultiSelection::SelectionList::iterator i = selections.begin();
                 i != selections.end(); ++i) {
                layer->deleteSelection(*i);
            }
	}
    }
}

void
MainWindowBase::insertInstant()
{
    int frame = m_viewManager->getPlaybackFrame();
    insertInstantAt(frame);
}

void
MainWindowBase::insertInstantsAtBoundaries()
{
    MultiSelection::SelectionList selections = m_viewManager->getSelections();
    for (MultiSelection::SelectionList::iterator i = selections.begin();
         i != selections.end(); ++i) {
        size_t start = i->getStartFrame();
        size_t end = i->getEndFrame();
        if (start != end) {
            insertInstantAt(i->getStartFrame());
            insertInstantAt(i->getEndFrame());
        }
    }
}

void
MainWindowBase::insertInstantAt(size_t frame)
{
    Pane *pane = m_paneStack->getCurrentPane();
    if (!pane) {
        return;
    }

    frame = pane->alignFromReference(frame);

    Layer *layer = dynamic_cast<TimeInstantLayer *>
        (pane->getSelectedLayer());

    if (!layer) {
        for (int i = pane->getLayerCount(); i > 0; --i) {
            layer = dynamic_cast<TimeInstantLayer *>(pane->getLayer(i - 1));
            if (layer) break;
        }

        if (!layer) {
            CommandHistory::getInstance()->startCompoundOperation
                (tr("Add Point"), true);
            layer = m_document->createEmptyLayer(LayerFactory::TimeInstants);
            if (layer) {
                m_document->addLayerToView(pane, layer);
                m_paneStack->setCurrentLayer(pane, layer);
            }
            CommandHistory::getInstance()->endCompoundOperation();
        }
    }

    if (layer) {
    
        Model *model = layer->getModel();
        SparseOneDimensionalModel *sodm = dynamic_cast<SparseOneDimensionalModel *>
            (model);

        if (sodm) {
            SparseOneDimensionalModel::Point point(frame, "");

            SparseOneDimensionalModel::Point prevPoint(0);
            bool havePrevPoint = false;

            SparseOneDimensionalModel::EditCommand *command =
                new SparseOneDimensionalModel::EditCommand(sodm, tr("Add Point"));

            if (m_labeller->requiresPrevPoint()) {

                SparseOneDimensionalModel::PointList prevPoints =
                    sodm->getPreviousPoints(frame);

                if (!prevPoints.empty()) {
                    prevPoint = *prevPoints.begin();
                    havePrevPoint = true;
                }
            }

            if (m_labeller) {

                m_labeller->setSampleRate(sodm->getSampleRate());

                if (m_labeller->actingOnPrevPoint()) {
                    command->deletePoint(prevPoint);
                }

                m_labeller->label<SparseOneDimensionalModel::Point>
                    (point, havePrevPoint ? &prevPoint : 0);

                if (m_labeller->actingOnPrevPoint()) {
                    command->addPoint(prevPoint);
                }
            }
            
            command->addPoint(point);

            command->setName(tr("Add Point at %1 s")
                             .arg(RealTime::frame2RealTime
                                  (frame,
                                   sodm->getSampleRate())
                                  .toText(false).c_str()));

            command->finish();
        }
    }
}

void
MainWindowBase::renumberInstants()
{
    Pane *pane = m_paneStack->getCurrentPane();
    if (!pane) return;

    Layer *layer = dynamic_cast<TimeInstantLayer *>(pane->getSelectedLayer());
    if (!layer) return;

    MultiSelection ms(m_viewManager->getSelection());
    
    Model *model = layer->getModel();
    SparseOneDimensionalModel *sodm = dynamic_cast<SparseOneDimensionalModel *>
        (model);
    if (!sodm) return;

    if (!m_labeller) return;

    Labeller labeller(*m_labeller);
    labeller.setSampleRate(sodm->getSampleRate());

    // This uses a command

    labeller.labelAll<SparseOneDimensionalModel::Point>(*sodm, &ms);
}

MainWindowBase::FileOpenStatus
MainWindowBase::open(QString fileOrUrl, AudioFileOpenMode mode)
{
    return open(FileSource(fileOrUrl, FileSource::ProgressDialog), mode);
}

MainWindowBase::FileOpenStatus
MainWindowBase::open(FileSource source, AudioFileOpenMode mode)
{
    FileOpenStatus status;

    if (!source.isAvailable()) return FileOpenFailed;
    source.waitForData();

    bool canImportLayer = (getMainModel() != 0 &&
                           m_paneStack != 0 &&
                           m_paneStack->getCurrentPane() != 0);

    if ((status = openAudio(source, mode)) != FileOpenFailed) {
        return status;
    } else if ((status = openSession(source)) != FileOpenFailed) {
	return status;
    } else if ((status = openPlaylist(source, mode)) != FileOpenFailed) {
        return status;
    } else if (!canImportLayer) {
        return FileOpenWrongMode;
    } else if ((status = openImage(source)) != FileOpenFailed) {
        return status;
    } else if ((status = openLayer(source)) != FileOpenFailed) {
        return status;
    } else {
	return FileOpenFailed;
    }
}

MainWindowBase::FileOpenStatus
MainWindowBase::openAudio(FileSource source, AudioFileOpenMode mode)
{
    std::cerr << "MainWindowBase::openAudio(" << source.getLocation().toStdString() << ")" << std::endl;

    if (!source.isAvailable()) return FileOpenFailed;
    source.waitForData();

    m_openingAudioFile = true;

    size_t rate = 0;

    if (Preferences::getInstance()->getResampleOnLoad()) {
        rate = m_playSource->getSourceSampleRate();
    }

    WaveFileModel *newModel = new WaveFileModel(source, rate);

    if (!newModel->isOK()) {
	delete newModel;
        m_openingAudioFile = false;
	return FileOpenFailed;
    }

    std::cerr << "mode = " << mode << std::endl;

    if (mode == AskUser) {
        if (getMainModel()) {

            static bool prevSetAsMain = true;
            bool setAsMain = true;
            
            QStringList items;
            items << tr("Replace the existing main waveform")
                  << tr("Load this file into a new waveform pane");

            bool ok = false;
            QString item = ListInputDialog::getItem
                (this, tr("Select target for import"),
                 tr("You already have an audio waveform loaded.\nWhat would you like to do with the new audio file?"),
                 items, prevSetAsMain ? 0 : 1, &ok);
            
            if (!ok || item.isEmpty()) {
                delete newModel;
                m_openingAudioFile = false;
                return FileOpenCancelled;
            }
            
            setAsMain = (item == items[0]);
            prevSetAsMain = setAsMain;

            if (setAsMain) mode = ReplaceMainModel;
            else mode = CreateAdditionalModel;

        } else {
            mode = ReplaceMainModel;
        }
    }

    if (mode == ReplaceCurrentPane) {

        Pane *pane = m_paneStack->getCurrentPane();
        if (pane) {
            if (getMainModel()) {
                View::ModelSet models(pane->getModels());
                if (models.find(getMainModel()) != models.end()) {
                    mode = ReplaceMainModel;
                }
            } else {
                mode = ReplaceMainModel;
            }
        } else {
            mode = CreateAdditionalModel;
        }
    }

    if (mode == CreateAdditionalModel && !getMainModel()) {
        mode = ReplaceMainModel;
    }

    if (mode == ReplaceMainModel) {

        Model *prevMain = getMainModel();
        if (prevMain) {
            m_playSource->removeModel(prevMain);
            PlayParameterRepository::getInstance()->removeModel(prevMain);
        }
        PlayParameterRepository::getInstance()->addModel(newModel);

	m_document->setMainModel(newModel);

	setupMenus();

	if (m_sessionFile == "") {
            //!!! shouldn't be dealing directly with title from here -- call a method
	    setWindowTitle(tr("%1: %2")
                           .arg(QApplication::applicationName())
                           .arg(source.getLocation()));
	    CommandHistory::getInstance()->clear();
	    CommandHistory::getInstance()->documentSaved();
	    m_documentModified = false;
	} else {
	    setWindowTitle(tr("%1: %2 [%3]")
                           .arg(QApplication::applicationName())
			   .arg(QFileInfo(m_sessionFile).fileName())
			   .arg(source.getLocation()));
	    if (m_documentModified) {
		m_documentModified = false;
		documentModified(); // so as to restore "(modified)" window title
	    }
	}

        if (!source.isRemote()) m_audioFile = source.getLocalFilename();

    } else if (mode == CreateAdditionalModel) {

	CommandHistory::getInstance()->startCompoundOperation
	    (tr("Import \"%1\"").arg(source.getLocation()), true);

	m_document->addImportedModel(newModel);

	AddPaneCommand *command = new AddPaneCommand(this);
	CommandHistory::getInstance()->addCommand(command);

	Pane *pane = command->getPane();

        if (m_timeRulerLayer) {
            m_document->addLayerToView(pane, m_timeRulerLayer);
        }

	Layer *newLayer = m_document->createImportedLayer(newModel);

	if (newLayer) {
	    m_document->addLayerToView(pane, newLayer);
	}
	
	CommandHistory::getInstance()->endCompoundOperation();

    } else if (mode == ReplaceCurrentPane) {

        // We know there is a current pane, otherwise we would have
        // reset the mode to CreateAdditionalModel above; and we know
        // the current pane does not contain the main model, otherwise
        // we would have reset it to ReplaceMainModel.  But we don't
        // know whether the pane contains a waveform model at all.
        
        Pane *pane = m_paneStack->getCurrentPane();
        Layer *replace = 0;

        for (int i = 0; i < pane->getLayerCount(); ++i) {
            Layer *layer = pane->getLayer(i);
            if (dynamic_cast<WaveformLayer *>(layer)) {
                replace = layer;
                break;
            }
        }

	CommandHistory::getInstance()->startCompoundOperation
	    (tr("Import \"%1\"").arg(source.getLocation()), true);

	m_document->addImportedModel(newModel);

        if (replace) {
            m_document->removeLayerFromView(pane, replace);
        }

	Layer *newLayer = m_document->createImportedLayer(newModel);

	if (newLayer) {
	    m_document->addLayerToView(pane, newLayer);
	}
	
	CommandHistory::getInstance()->endCompoundOperation();
    }

    updateMenuStates();
    m_recentFiles.addFile(source.getLocation());
    if (!source.isRemote()) {
        // for file dialog
        registerLastOpenedFilePath(FileFinder::AudioFile,
                                   source.getLocalFilename());
    }
    m_openingAudioFile = false;

    currentPaneChanged(m_paneStack->getCurrentPane());

    return FileOpenSucceeded;
}

MainWindowBase::FileOpenStatus
MainWindowBase::openPlaylist(FileSource source, AudioFileOpenMode mode)
{
    std::set<QString> extensions;
    PlaylistFileReader::getSupportedExtensions(extensions);
    QString extension = source.getExtension();
    if (extensions.find(extension) == extensions.end()) return FileOpenFailed;

    if (!source.isAvailable()) return FileOpenFailed;
    source.waitForData();

    PlaylistFileReader reader(source.getLocalFilename());
    if (!reader.isOK()) return FileOpenFailed;

    PlaylistFileReader::Playlist playlist = reader.load();

    bool someSuccess = false;

    for (PlaylistFileReader::Playlist::const_iterator i = playlist.begin();
         i != playlist.end(); ++i) {

        FileOpenStatus status = openAudio
            (FileSource(*i, FileSource::ProgressDialog), mode);

        if (status == FileOpenCancelled) {
            return FileOpenCancelled;
        }

        if (status == FileOpenSucceeded) {
            someSuccess = true;
            mode = CreateAdditionalModel;
        }
    }

    if (someSuccess) return FileOpenSucceeded;
    else return FileOpenFailed;
}

MainWindowBase::FileOpenStatus
MainWindowBase::openLayer(FileSource source)
{
    Pane *pane = m_paneStack->getCurrentPane();
    
    if (!pane) {
	// shouldn't happen, as the menu action should have been disabled
	std::cerr << "WARNING: MainWindowBase::openLayer: no current pane" << std::endl;
	return FileOpenWrongMode;
    }

    if (!getMainModel()) {
	// shouldn't happen, as the menu action should have been disabled
	std::cerr << "WARNING: MainWindowBase::openLayer: No main model -- hence no default sample rate available" << std::endl;
	return FileOpenWrongMode;
    }

    if (!source.isAvailable()) return FileOpenFailed;
    source.waitForData();

    QString path = source.getLocalFilename();

    if (source.getExtension() == "svl" || source.getExtension() == "xml") {

        PaneCallback callback(this);
        QFile file(path);
        
        if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
            std::cerr << "ERROR: MainWindowBase::openLayer("
                      << source.getLocation().toStdString()
                      << "): Failed to open file for reading" << std::endl;
            return FileOpenFailed;
        }
        
        SVFileReader reader(m_document, callback, source.getLocation());
        reader.setCurrentPane(pane);
        
        QXmlInputSource inputSource(&file);
        reader.parse(inputSource);
        
        if (!reader.isOK()) {
            std::cerr << "ERROR: MainWindowBase::openLayer("
                      << source.getLocation().toStdString()
                      << "): Failed to read XML file: "
                      << reader.getErrorString().toStdString() << std::endl;
            return FileOpenFailed;
        }

        m_recentFiles.addFile(source.getLocation());

        if (!source.isRemote()) {
            registerLastOpenedFilePath(FileFinder::LayerFile, path); // for file dialog
        }

        return FileOpenSucceeded;

    } else {
        
        try {

            Model *model = DataFileReaderFactory::load
                (path, getMainModel()->getSampleRate());
        
            if (model) {

                std::cerr << "MainWindowBase::openLayer: Have model" << std::endl;

                Layer *newLayer = m_document->createImportedLayer(model);

                if (newLayer) {

                    m_document->addLayerToView(pane, newLayer);
                    m_recentFiles.addFile(source.getLocation());
                    
                    if (!source.isRemote()) {
                        registerLastOpenedFilePath
                            (FileFinder::LayerFile,
                             path); // for file dialog
                    }
                    
                    return FileOpenSucceeded;
                }
            }
        } catch (DataFileReaderFactory::Exception e) {
            if (e == DataFileReaderFactory::ImportCancelled) {
                return FileOpenCancelled;
            }
        }
    }
    
    return FileOpenFailed;
}

MainWindowBase::FileOpenStatus
MainWindowBase::openImage(FileSource source)
{
    Pane *pane = m_paneStack->getCurrentPane();
    
    if (!pane) {
	// shouldn't happen, as the menu action should have been disabled
	std::cerr << "WARNING: MainWindowBase::openImage: no current pane" << std::endl;
	return FileOpenWrongMode;
    }

    if (!m_document->getMainModel()) {
        return FileOpenWrongMode;
    }

    bool newLayer = false;

    ImageLayer *il = dynamic_cast<ImageLayer *>(pane->getSelectedLayer());
    if (!il) {
        for (int i = pane->getLayerCount()-1; i >= 0; --i) {
            il = dynamic_cast<ImageLayer *>(pane->getLayer(i));
            if (il) break;
        }
    }
    if (!il) {
        il = dynamic_cast<ImageLayer *>
            (m_document->createEmptyLayer(LayerFactory::Image));
        if (!il) return FileOpenFailed;
        newLayer = true;
    }

    // We don't put the image file in Recent Files

    std::cerr << "openImage: trying location \"" << source.getLocation().toStdString() << "\" in image layer" << std::endl;

    if (!il->addImage(m_viewManager->getGlobalCentreFrame(), source.getLocation())) {
        if (newLayer) {
            m_document->deleteLayer(il); // also releases its model
        }
        return FileOpenFailed;
    } else {
        if (newLayer) {
            m_document->addLayerToView(pane, il);
        }
        m_paneStack->setCurrentLayer(pane, il);
    }

    return FileOpenSucceeded;
}

MainWindowBase::FileOpenStatus
MainWindowBase::openSessionFile(QString fileOrUrl)
{
    return openSession(FileSource(fileOrUrl, FileSource::ProgressDialog));
}

MainWindowBase::FileOpenStatus
MainWindowBase::openSession(FileSource source)
{
    if (!source.isAvailable()) return FileOpenFailed;
    if (source.getExtension() != "sv") return FileOpenFailed;
    source.waitForData();

    BZipFileDevice bzFile(source.getLocalFilename());
    if (!bzFile.open(QIODevice::ReadOnly)) return FileOpenFailed;

    if (!checkSaveModified()) return FileOpenCancelled;

    QString error;
    closeSession();
    createDocument();

    PaneCallback callback(this);
    m_viewManager->clearSelections();

    SVFileReader reader(m_document, callback, source.getLocation());
    QXmlInputSource inputSource(&bzFile);
    reader.parse(inputSource);
    
    if (!reader.isOK()) {
        error = tr("SV XML file read error:\n%1").arg(reader.getErrorString());
    }
    
    bzFile.close();

    bool ok = (error == "");

    if (ok) {

	setWindowTitle(tr("%1: %2")
                       .arg(QApplication::applicationName())
		       .arg(source.getLocation()));

	if (!source.isRemote()) m_sessionFile = source.getLocalFilename();

	setupMenus();

	CommandHistory::getInstance()->clear();
	CommandHistory::getInstance()->documentSaved();
	m_documentModified = false;
	updateMenuStates();

        m_recentFiles.addFile(source.getLocation());

        if (!source.isRemote()) {
            // for file dialog
            registerLastOpenedFilePath(FileFinder::SessionFile,
                                        source.getLocalFilename());
        }

    } else {
	setWindowTitle(QApplication::applicationName());
    }

    return ok ? FileOpenSucceeded : FileOpenFailed;
}

void
MainWindowBase::createPlayTarget()
{
    if (m_playTarget) return;

    m_playTarget = AudioTargetFactory::createCallbackTarget(m_playSource);
    if (!m_playTarget) {
	QMessageBox::warning
	    (this, tr("Couldn't open audio device"),
	     tr("<b>No audio available</b><p>Could not open an audio device for playback.<p>Audio playback will not be available during this session."),
	     QMessageBox::Ok);
    }
}

WaveFileModel *
MainWindowBase::getMainModel()
{
    if (!m_document) return 0;
    return m_document->getMainModel();
}

const WaveFileModel *
MainWindowBase::getMainModel() const
{
    if (!m_document) return 0;
    return m_document->getMainModel();
}

void
MainWindowBase::createDocument()
{
    m_document = new Document;

    connect(m_document, SIGNAL(layerAdded(Layer *)),
	    this, SLOT(layerAdded(Layer *)));
    connect(m_document, SIGNAL(layerRemoved(Layer *)),
	    this, SLOT(layerRemoved(Layer *)));
    connect(m_document, SIGNAL(layerAboutToBeDeleted(Layer *)),
	    this, SLOT(layerAboutToBeDeleted(Layer *)));
    connect(m_document, SIGNAL(layerInAView(Layer *, bool)),
	    this, SLOT(layerInAView(Layer *, bool)));

    connect(m_document, SIGNAL(modelAdded(Model *)),
	    this, SLOT(modelAdded(Model *)));
    connect(m_document, SIGNAL(mainModelChanged(WaveFileModel *)),
	    this, SLOT(mainModelChanged(WaveFileModel *)));
    connect(m_document, SIGNAL(modelAboutToBeDeleted(Model *)),
	    this, SLOT(modelAboutToBeDeleted(Model *)));

    connect(m_document, SIGNAL(modelGenerationFailed(QString)),
            this, SLOT(modelGenerationFailed(QString)));
    connect(m_document, SIGNAL(modelRegenerationFailed(QString, QString)),
            this, SLOT(modelRegenerationFailed(QString, QString)));
}

bool
MainWindowBase::saveSessionFile(QString path)
{
    BZipFileDevice bzFile(path);
    if (!bzFile.open(QIODevice::WriteOnly)) {
        std::cerr << "Failed to open session file \"" << path.toStdString()
                  << "\" for writing: "
                  << bzFile.errorString().toStdString() << std::endl;
        return false;
    }

    QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));

    QTextStream out(&bzFile);
    toXml(out);
    out.flush();

    QApplication::restoreOverrideCursor();

    if (!bzFile.isOK()) {
	QMessageBox::critical(this, tr("Failed to write file"),
			      tr("<b>Save failed</b><p>Failed to write to file \"%1\": %2")
			      .arg(path).arg(bzFile.errorString()));
        bzFile.close();
	return false;
    }

    bzFile.close();
    return true;
}

void
MainWindowBase::toXml(QTextStream &out)
{
    QString indent("  ");

    out << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
    out << "<!DOCTYPE sonic-visualiser>\n";
    out << "<sv>\n";

    m_document->toXml(out, "", "");

    out << "<display>\n";

    out << QString("  <window width=\"%1\" height=\"%2\"/>\n")
	.arg(width()).arg(height());

    for (int i = 0; i < m_paneStack->getPaneCount(); ++i) {

	Pane *pane = m_paneStack->getPane(i);

	if (pane) {
            pane->toXml(out, indent);
	}
    }

    out << "</display>\n";

    m_viewManager->getSelection().toXml(out);

    out << "</sv>\n";
}

Pane *
MainWindowBase::addPaneToStack()
{
    AddPaneCommand *command = new AddPaneCommand(this);
    CommandHistory::getInstance()->addCommand(command);
    Pane *pane = command->getPane();
    return pane;
}

void
MainWindowBase::zoomIn()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentPane->zoom(true);
}

void
MainWindowBase::zoomOut()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentPane->zoom(false);
}

void
MainWindowBase::zoomToFit()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    Model *model = getMainModel();
    if (!model) return;
    
    size_t start = model->getStartFrame();
    size_t end = model->getEndFrame();
    if (m_playSource) end = std::max(end, m_playSource->getPlayEndFrame());
    size_t pixels = currentPane->width();

    size_t sw = currentPane->getVerticalScaleWidth();
    if (pixels > sw * 2) pixels -= sw * 2;
    else pixels = 1;
    if (pixels > 4) pixels -= 4;

    size_t zoomLevel = (end - start) / pixels;

    currentPane->setZoomLevel(zoomLevel);
    currentPane->setCentreFrame((start + end) / 2);
}

void
MainWindowBase::zoomDefault()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentPane->setZoomLevel(1024);
}

void
MainWindowBase::scrollLeft()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentPane->scroll(false, false);
}

void
MainWindowBase::jumpLeft()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentPane->scroll(false, true);
}

void
MainWindowBase::scrollRight()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentPane->scroll(true, false);
}

void
MainWindowBase::jumpRight()
{
    Pane *currentPane = m_paneStack->getCurrentPane();
    if (currentPane) currentPane->scroll(true, true);
}

void
MainWindowBase::showNoOverlays()
{
    m_viewManager->setOverlayMode(ViewManager::NoOverlays);
}

void
MainWindowBase::showMinimalOverlays()
{
    m_viewManager->setOverlayMode(ViewManager::MinimalOverlays);
}

void
MainWindowBase::showStandardOverlays()
{
    m_viewManager->setOverlayMode(ViewManager::StandardOverlays);
}

void
MainWindowBase::showAllOverlays()
{
    m_viewManager->setOverlayMode(ViewManager::AllOverlays);
}

void
MainWindowBase::toggleZoomWheels()
{
    if (m_viewManager->getZoomWheelsEnabled()) {
        m_viewManager->setZoomWheelsEnabled(false);
    } else {
        m_viewManager->setZoomWheelsEnabled(true);
    }
}

void
MainWindowBase::togglePropertyBoxes()
{
    if (m_paneStack->getLayoutStyle() == PaneStack::NoPropertyStacks) {
        if (Preferences::getInstance()->getPropertyBoxLayout() ==
            Preferences::VerticallyStacked) {
            m_paneStack->setLayoutStyle(PaneStack::PropertyStackPerPaneLayout);
        } else {
            m_paneStack->setLayoutStyle(PaneStack::SinglePropertyStackLayout);
        }
    } else {
        m_paneStack->setLayoutStyle(PaneStack::NoPropertyStacks);
    }
}

void
MainWindowBase::toggleStatusBar()
{
    QSettings settings;
    settings.beginGroup("MainWindow");
    bool sb = settings.value("showstatusbar", true).toBool();

    if (sb) {
        statusBar()->hide();
    } else {
        statusBar()->show();
    }

    settings.setValue("showstatusbar", !sb);

    settings.endGroup();
}

void
MainWindowBase::preferenceChanged(PropertyContainer::PropertyName name)
{
    if (name == "Property Box Layout") {
        if (m_paneStack->getLayoutStyle() != PaneStack::NoPropertyStacks) {
            if (Preferences::getInstance()->getPropertyBoxLayout() ==
                Preferences::VerticallyStacked) {
                m_paneStack->setLayoutStyle(PaneStack::PropertyStackPerPaneLayout);
            } else {
                m_paneStack->setLayoutStyle(PaneStack::SinglePropertyStackLayout);
            }
        }
    } else if (name == "Background Mode" && m_viewManager) {
        Preferences::BackgroundMode mode =
            Preferences::getInstance()->getBackgroundMode();
        if (mode == Preferences::BackgroundFromTheme) {
            m_viewManager->setGlobalDarkBackground(m_initialDarkBackground);
        } else if (mode == Preferences::DarkBackground) {
            m_viewManager->setGlobalDarkBackground(true);
        } else {
            m_viewManager->setGlobalDarkBackground(false);
        }
    }            
}

void
MainWindowBase::play()
{
    if (m_playSource->isPlaying()) {
        stop();
    } else {
        playbackFrameChanged(m_viewManager->getPlaybackFrame());
	m_playSource->play(m_viewManager->getPlaybackFrame());
    }
}

void
MainWindowBase::ffwd()
{
    if (!getMainModel()) return;

    int frame = m_viewManager->getPlaybackFrame();
    ++frame;

    Layer *layer = getSnapLayer();
    size_t sr = getMainModel()->getSampleRate();

    if (!layer) {

        frame = RealTime::realTime2Frame
            (RealTime::frame2RealTime(frame, sr) + RealTime(2, 0), sr);
        if (frame > int(getMainModel()->getEndFrame())) {
            frame = getMainModel()->getEndFrame();
        }

    } else {

        size_t resolution = 0;
        if (!layer->snapToFeatureFrame(m_paneStack->getCurrentPane(),
                                       frame, resolution, Layer::SnapRight)) {
            frame = getMainModel()->getEndFrame();
        }
    }
        
    if (frame < 0) frame = 0;

    if (m_viewManager->getPlaySelectionMode()) {
        frame = m_viewManager->constrainFrameToSelection(size_t(frame));
    }
    
    m_viewManager->setPlaybackFrame(frame);
}

void
MainWindowBase::ffwdEnd()
{
    if (!getMainModel()) return;

    size_t frame = getMainModel()->getEndFrame();

    if (m_viewManager->getPlaySelectionMode()) {
        frame = m_viewManager->constrainFrameToSelection(frame);
    }

    m_viewManager->setPlaybackFrame(frame);
}

void
MainWindowBase::rewind()
{
    if (!getMainModel()) return;

    int frame = m_viewManager->getPlaybackFrame();
    if (frame > 0) --frame;

    Layer *layer = getSnapLayer();
    size_t sr = getMainModel()->getSampleRate();
    
    // when rewinding during playback, we want to allow a period
    // following a rewind target point at which the rewind will go to
    // the prior point instead of the immediately neighbouring one
    if (m_playSource && m_playSource->isPlaying()) {
        RealTime ct = RealTime::frame2RealTime(frame, sr);
        ct = ct - RealTime::fromSeconds(0.25);
        if (ct < RealTime::zeroTime) ct = RealTime::zeroTime;
//        std::cerr << "rewind: frame " << frame << " -> ";
        frame = RealTime::realTime2Frame(ct, sr);
//        std::cerr << frame << std::endl;
    }

    if (!layer) {
        
        frame = RealTime::realTime2Frame
            (RealTime::frame2RealTime(frame, sr) - RealTime(2, 0), sr);
        if (frame < int(getMainModel()->getStartFrame())) {
            frame = getMainModel()->getStartFrame();
        }

    } else {

        size_t resolution = 0;
        if (!layer->snapToFeatureFrame(m_paneStack->getCurrentPane(),
                                       frame, resolution, Layer::SnapLeft)) {
            frame = getMainModel()->getStartFrame();
        }
    }

    if (frame < 0) frame = 0;

    if (m_viewManager->getPlaySelectionMode()) {
        frame = m_viewManager->constrainFrameToSelection(size_t(frame));
    }

    m_viewManager->setPlaybackFrame(frame);
}

void
MainWindowBase::rewindStart()
{
    if (!getMainModel()) return;

    size_t frame = getMainModel()->getStartFrame();

    if (m_viewManager->getPlaySelectionMode()) {
        frame = m_viewManager->constrainFrameToSelection(frame);
    }

    m_viewManager->setPlaybackFrame(frame);
}

Layer *
MainWindowBase::getSnapLayer() const
{
    Pane *pane = m_paneStack->getCurrentPane();
    if (!pane) return 0;

    Layer *layer = pane->getSelectedLayer();

    if (!dynamic_cast<TimeInstantLayer *>(layer) &&
        !dynamic_cast<TimeValueLayer *>(layer) &&
        !dynamic_cast<TimeRulerLayer *>(layer)) {

        layer = 0;

        for (int i = pane->getLayerCount(); i > 0; --i) {
            Layer *l = pane->getLayer(i-1);
            if (dynamic_cast<TimeRulerLayer *>(l)) {
                layer = l;
                break;
            }
        }
    }

    return layer;
}

void
MainWindowBase::stop()
{
    m_playSource->stop();

    if (m_paneStack && m_paneStack->getCurrentPane()) {
        updateVisibleRangeDisplay(m_paneStack->getCurrentPane());
    } else {
        m_myStatusMessage = "";
        statusBar()->showMessage("");
    }
}

MainWindowBase::AddPaneCommand::AddPaneCommand(MainWindowBase *mw) :
    m_mw(mw),
    m_pane(0),
    m_prevCurrentPane(0),
    m_added(false)
{
}

MainWindowBase::AddPaneCommand::~AddPaneCommand()
{
    if (m_pane && !m_added) {
	m_mw->m_paneStack->deletePane(m_pane);
    }
}

QString
MainWindowBase::AddPaneCommand::getName() const
{
    return tr("Add Pane");
}

void
MainWindowBase::AddPaneCommand::execute()
{
    if (!m_pane) {
	m_prevCurrentPane = m_mw->m_paneStack->getCurrentPane();
	m_pane = m_mw->m_paneStack->addPane();

        connect(m_pane, SIGNAL(contextHelpChanged(const QString &)),
                m_mw, SLOT(contextHelpChanged(const QString &)));
    } else {
	m_mw->m_paneStack->showPane(m_pane);
    }

    m_mw->m_paneStack->setCurrentPane(m_pane);
    m_added = true;
}

void
MainWindowBase::AddPaneCommand::unexecute()
{
    m_mw->m_paneStack->hidePane(m_pane);
    m_mw->m_paneStack->setCurrentPane(m_prevCurrentPane);
    m_added = false;
}

MainWindowBase::RemovePaneCommand::RemovePaneCommand(MainWindowBase *mw, Pane *pane) :
    m_mw(mw),
    m_pane(pane),
    m_added(true)
{
}

MainWindowBase::RemovePaneCommand::~RemovePaneCommand()
{
    if (m_pane && !m_added) {
	m_mw->m_paneStack->deletePane(m_pane);
    }
}

QString
MainWindowBase::RemovePaneCommand::getName() const
{
    return tr("Remove Pane");
}

void
MainWindowBase::RemovePaneCommand::execute()
{
    m_prevCurrentPane = m_mw->m_paneStack->getCurrentPane();
    m_mw->m_paneStack->hidePane(m_pane);
    m_added = false;
}

void
MainWindowBase::RemovePaneCommand::unexecute()
{
    m_mw->m_paneStack->showPane(m_pane);
    m_mw->m_paneStack->setCurrentPane(m_prevCurrentPane);
    m_added = true;
}

void
MainWindowBase::deleteCurrentPane()
{
    CommandHistory::getInstance()->startCompoundOperation
	(tr("Delete Pane"), true);

    Pane *pane = m_paneStack->getCurrentPane();
    if (pane) {
	while (pane->getLayerCount() > 0) {
	    Layer *layer = pane->getLayer(0);
	    if (layer) {
		m_document->removeLayerFromView(pane, layer);
	    } else {
		break;
	    }
	}

	RemovePaneCommand *command = new RemovePaneCommand(this, pane);
	CommandHistory::getInstance()->addCommand(command);
    }

    CommandHistory::getInstance()->endCompoundOperation();

    updateMenuStates();
}

void
MainWindowBase::deleteCurrentLayer()
{
    Pane *pane = m_paneStack->getCurrentPane();
    if (pane) {
	Layer *layer = pane->getSelectedLayer();
	if (layer) {
	    m_document->removeLayerFromView(pane, layer);
	}
    }
    updateMenuStates();
}

void
MainWindowBase::previousPane()
{
    if (!m_paneStack) return;

    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    for (int i = 0; i < m_paneStack->getPaneCount(); ++i) {
        if (m_paneStack->getPane(i) == currentPane) {
            if (i == 0) return;
            m_paneStack->setCurrentPane(m_paneStack->getPane(i-1));
            updateMenuStates();
            return;
        }
    }
}

void
MainWindowBase::nextPane()
{
    if (!m_paneStack) return;

    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    for (int i = 0; i < m_paneStack->getPaneCount(); ++i) {
        if (m_paneStack->getPane(i) == currentPane) {
            if (i == m_paneStack->getPaneCount()-1) return;
            m_paneStack->setCurrentPane(m_paneStack->getPane(i+1));
            updateMenuStates();
            return;
        }
    }
}

void
MainWindowBase::previousLayer()
{
    //!!! Not right -- pane lists layers in stacking order

    if (!m_paneStack) return;

    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    Layer *currentLayer = currentPane->getSelectedLayer();
    if (!currentLayer) return;

    for (int i = 0; i < currentPane->getLayerCount(); ++i) {
        if (currentPane->getLayer(i) == currentLayer) {
            if (i == 0) return;
            m_paneStack->setCurrentLayer(currentPane,
                                         currentPane->getLayer(i-1));
            updateMenuStates();
            return;
        }
    }
}

void
MainWindowBase::nextLayer()
{
    //!!! Not right -- pane lists layers in stacking order

    if (!m_paneStack) return;

    Pane *currentPane = m_paneStack->getCurrentPane();
    if (!currentPane) return;

    Layer *currentLayer = currentPane->getSelectedLayer();
    if (!currentLayer) return;

    for (int i = 0; i < currentPane->getLayerCount(); ++i) {
        if (currentPane->getLayer(i) == currentLayer) {
            if (i == currentPane->getLayerCount()-1) return;
            m_paneStack->setCurrentLayer(currentPane,
                                         currentPane->getLayer(i+1));
            updateMenuStates();
            return;
        }
    }
}

void
MainWindowBase::playbackFrameChanged(unsigned long frame)
{
    if (!(m_playSource && m_playSource->isPlaying()) || !getMainModel()) return;

    RealTime now = RealTime::frame2RealTime
        (frame, getMainModel()->getSampleRate());

    if (now.sec == m_lastPlayStatusSec) return;

    RealTime then = RealTime::frame2RealTime
        (m_playSource->getPlayEndFrame(), getMainModel()->getSampleRate());

    QString nowStr;
    QString thenStr;
    QString remainingStr;

    if (then.sec > 10) {
        nowStr = now.toSecText().c_str();
        thenStr = then.toSecText().c_str();
        remainingStr = (then - now).toSecText().c_str();
        m_lastPlayStatusSec = now.sec;
    } else {
        nowStr = now.toText(true).c_str();
        thenStr = then.toText(true).c_str();
        remainingStr = (then - now).toText(true).c_str();
    }        

    m_myStatusMessage = tr("Playing: %1 of %2 (%3 remaining)")
        .arg(nowStr).arg(thenStr).arg(remainingStr);

    statusBar()->showMessage(m_myStatusMessage);
}

void
MainWindowBase::globalCentreFrameChanged(unsigned long )
{
    if ((m_playSource && m_playSource->isPlaying()) || !getMainModel()) return;
    Pane *p = 0;
    if (!m_paneStack || !(p = m_paneStack->getCurrentPane())) return;
    if (!p->getFollowGlobalPan()) return;
    updateVisibleRangeDisplay(p);
}

void
MainWindowBase::viewCentreFrameChanged(View *v, unsigned long )
{
    if ((m_playSource && m_playSource->isPlaying()) || !getMainModel()) return;
    Pane *p = 0;
    if (!m_paneStack || !(p = m_paneStack->getCurrentPane())) return;
    if (v == p) updateVisibleRangeDisplay(p);
}

void
MainWindowBase::viewZoomLevelChanged(View *v, unsigned long , bool )
{
    if ((m_playSource && m_playSource->isPlaying()) || !getMainModel()) return;
    Pane *p = 0;
    if (!m_paneStack || !(p = m_paneStack->getCurrentPane())) return;
    if (v == p) updateVisibleRangeDisplay(p);
}

void
MainWindowBase::layerAdded(Layer *)
{
//    std::cerr << "MainWindowBase::layerAdded(" << layer << ")" << std::endl;
    updateMenuStates();
}

void
MainWindowBase::layerRemoved(Layer *)
{
//    std::cerr << "MainWindowBase::layerRemoved(" << layer << ")" << std::endl;
    updateMenuStates();
}

void
MainWindowBase::layerAboutToBeDeleted(Layer *layer)
{
//    std::cerr << "MainWindowBase::layerAboutToBeDeleted(" << layer << ")" << std::endl;
    if (m_timeRulerLayer && (layer == m_timeRulerLayer)) {
//	std::cerr << "(this is the time ruler layer)" << std::endl;
	m_timeRulerLayer = 0;
    }
}

void
MainWindowBase::layerInAView(Layer *layer, bool inAView)
{
//    std::cerr << "MainWindowBase::layerInAView(" << layer << "," << inAView << ")" << std::endl;

    // Check whether we need to add or remove model from play source
    Model *model = layer->getModel();
    if (model) {
        if (inAView) {
            m_playSource->addModel(model);
        } else {
            bool found = false;
            for (int i = 0; i < m_paneStack->getPaneCount(); ++i) {
                Pane *pane = m_paneStack->getPane(i);
                if (!pane) continue;
                for (int j = 0; j < pane->getLayerCount(); ++j) {
                    Layer *pl = pane->getLayer(j);
                    if (pl && pl->getModel() == model) {
                        found = true;
                        break;
                    }
                }
                if (found) break;
            }
            if (!found) m_playSource->removeModel(model);
        }
    }

    updateMenuStates();
}

void
MainWindowBase::modelAdded(Model *model)
{
//    std::cerr << "MainWindowBase::modelAdded(" << model << ")" << std::endl;
    m_playSource->addModel(model);
}

void
MainWindowBase::mainModelChanged(WaveFileModel *model)
{
//    std::cerr << "MainWindowBase::mainModelChanged(" << model << ")" << std::endl;
    updateDescriptionLabel();
    if (model) m_viewManager->setMainModelSampleRate(model->getSampleRate());
    if (model && !m_playTarget && m_audioOutput) createPlayTarget();
}

void
MainWindowBase::modelAboutToBeDeleted(Model *model)
{
//    std::cerr << "MainWindowBase::modelAboutToBeDeleted(" << model << ")" << std::endl;
    if (model == m_viewManager->getPlaybackModel()) {
        m_viewManager->setPlaybackModel(0);
    }
    m_playSource->removeModel(model);
    FFTDataServer::modelAboutToBeDeleted(model);
}

void
MainWindowBase::paneDeleteButtonClicked(Pane *pane)
{
    bool found = false;
    for (int i = 0; i < m_paneStack->getPaneCount(); ++i) {
        if (m_paneStack->getPane(i) == pane) {
            found = true;
            break;
        }
    }
    if (!found) {
        std::cerr << "MainWindowBase::paneDeleteButtonClicked: Unknown pane "
                  << pane << std::endl;
        return;
    }

    CommandHistory::getInstance()->startCompoundOperation
	(tr("Delete Pane"), true);

    while (pane->getLayerCount() > 0) {
        Layer *layer = pane->getLayer(0);
        if (layer) {
            m_document->removeLayerFromView(pane, layer);
        } else {
            break;
        }
    }

    RemovePaneCommand *command = new RemovePaneCommand(this, pane);
    CommandHistory::getInstance()->addCommand(command);

    CommandHistory::getInstance()->endCompoundOperation();

    updateMenuStates();
}

void
MainWindowBase::pollOSC()
{
    if (!m_oscQueue || m_oscQueue->isEmpty()) return;
    std::cerr << "MainWindowBase::pollOSC: have " << m_oscQueue->getMessagesAvailable() << " messages" << std::endl;

    if (m_openingAudioFile) return;

    OSCMessage message = m_oscQueue->readMessage();

    if (message.getTarget() != 0) {
        return; //!!! for now -- this class is target 0, others not handled yet
    }

    handleOSCMessage(message);
}

void
MainWindowBase::inProgressSelectionChanged()
{
    Pane *currentPane = 0;
    if (m_paneStack) currentPane = m_paneStack->getCurrentPane();
    if (currentPane) updateVisibleRangeDisplay(currentPane);
}

void
MainWindowBase::contextHelpChanged(const QString &s)
{
    if (s == "" && m_myStatusMessage != "") {
        statusBar()->showMessage(m_myStatusMessage);
        return;
    }
    statusBar()->showMessage(s);
}

void
MainWindowBase::openHelpUrl(QString url)
{
    // This method mostly lifted from Qt Assistant source code

    QProcess *process = new QProcess(this);
    connect(process, SIGNAL(finished(int)), process, SLOT(deleteLater()));

    QStringList args;

#ifdef Q_OS_MAC
    args.append(url);
    process->start("open", args);
#else
#ifdef Q_OS_WIN32

	QString pf(getenv("ProgramFiles"));
	QString command = pf + QString("\\Internet Explorer\\IEXPLORE.EXE");

	args.append(url);
	process->start(command, args);

#else
#ifdef Q_WS_X11
    if (!qgetenv("KDE_FULL_SESSION").isEmpty()) {
        args.append("exec");
        args.append(url);
        process->start("kfmclient", args);
    } else if (!qgetenv("BROWSER").isEmpty()) {
        args.append(url);
        process->start(qgetenv("BROWSER"), args);
    } else {
        args.append(url);
        process->start("firefox", args);
    }
#endif
#endif
#endif
}