view view/View.h @ 317:e251c3599ea8

* Make RemoteFile far more pervasive, and use it for local files as well
  so that we can handle both transparently.  Make it shallow copy with
  reference counting, so it can be used by value without having to worry
  about the cache file lifetime.  Use RemoteFile for MainWindow file-open
  functions, etc

/* -*- 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 Chris Cannam.
    
    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.
*/

#ifndef _VIEW_H_
#define _VIEW_H_

#include <QFrame>
#include <QProgressBar>

#include "base/ZoomConstraint.h"
#include "base/PropertyContainer.h"
#include "ViewManager.h"
#include "base/XmlExportable.h"

// #define DEBUG_VIEW_WIDGET_PAINT 1

class Layer;
class ViewPropertyContainer;

#include <map>
#include <set>

/**
 * View is the base class of widgets that display one or more
 * overlaid views of data against a horizontal time scale. 
 *
 * A View may have any number of attached Layers, each of which
 * is expected to have one data Model (although multiple views may
 * share the same model).
 *
 * A View may be panned in time and zoomed, although the
 * mechanisms for doing so (as well as any other operations and
 * properties available) depend on the subclass.
 */

class View : public QFrame,
	     public XmlExportable
{
    Q_OBJECT

public:
    /**
     * Deleting a View does not delete any of its layers.  They should
     * be managed elsewhere (e.g. by the Document).
     */
    virtual ~View();

    /**
     * Retrieve the first visible sample frame on the widget.
     * This is a calculated value based on the centre-frame, widget
     * width and zoom level.  The result may be negative.
     */
    long getStartFrame() const;

    /**
     * Set the widget pan based on the given first visible frame.  The
     * frame value may be negative.
     */
    void setStartFrame(long);

    /**
     * Return the centre frame of the visible widget.  This is an
     * exact value that does not depend on the zoom block size.  Other
     * frame values (start, end) are calculated from this based on the
     * zoom and other factors.
     */
    size_t getCentreFrame() const { return m_centreFrame; }

    /**
     * Set the centre frame of the visible widget.
     */
    void setCentreFrame(size_t f) { setCentreFrame(f, true); }

    /**
     * Retrieve the last visible sample frame on the widget.
     * This is a calculated value based on the centre-frame, widget
     * width and zoom level.
     */
    size_t getEndFrame() const;

    /**
     * Return the pixel x-coordinate corresponding to a given sample
     * frame (which may be negative).
     */
    int getXForFrame(long frame) const;

    /**
     * Return the closest frame to the given pixel x-coordinate.
     */
    long getFrameForX(int x) const;

    /**
     * Return the pixel y-coordinate corresponding to a given
     * frequency, if the frequency range is as specified.  This does
     * not imply any policy about layer frequency ranges, but it might
     * be useful for layers to match theirs up if desired.
     *
     * Not thread-safe in logarithmic mode.  Call only from GUI thread.
     */
    float getYForFrequency(float frequency, float minFreq, float maxFreq, 
			   bool logarithmic) const;

    /**
     * Return the closest frequency to the given pixel y-coordinate,
     * if the frequency range is as specified.
     *
     * Not thread-safe in logarithmic mode.  Call only from GUI thread.
     */
    float getFrequencyForY(int y, float minFreq, float maxFreq,
			   bool logarithmic) const;

    /**
     * Return the zoom level, i.e. the number of frames per pixel
     */
    int getZoomLevel() const;

    /**
     * Set the zoom level, i.e. the number of frames per pixel.  The
     * centre frame will be unchanged; the start and end frames will
     * change.
     */
    virtual void setZoomLevel(size_t z);

    /**
     * Zoom in or out.
     */
    virtual void zoom(bool in);

    /**
     * Scroll left or right by a smallish or largish amount.
     */
    virtual void scroll(bool right, bool lots);

    virtual void addLayer(Layer *v);
    virtual void removeLayer(Layer *v); // does not delete the layer
    virtual int getLayerCount() const { return m_layers.size(); }

    /**
     * Return a layer, counted in stacking order.  That is, layer 0 is
     * the bottom layer and layer "getLayerCount()-1" is the top one.
     */
    virtual Layer *getLayer(int n) {
        if (n < int(m_layers.size())) return m_layers[n]; else return 0;
    }

    /**
     * Return the top layer.  This is the same as
     * getLayer(getLayerCount()-1) if there is at least one layer, and
     * 0 otherwise.
     */
    virtual Layer *getTopLayer() {
        return m_layers.empty() ? 0 : m_layers[m_layers.size()-1];
    }

    /**
     * Return the layer last selected by the user.  This is normally
     * the top layer, the same as getLayer(getLayerCount()-1).
     * However, if the user has selected the pane itself more recently
     * than any of the layers on it, this function will return 0.  It
     * will also return 0 if there are no layers.
     */
    virtual Layer *getSelectedLayer();
    virtual const Layer *getSelectedLayer() const;

    virtual void setViewManager(ViewManager *m);
    virtual ViewManager *getViewManager() const { return m_manager; }

    virtual void setFollowGlobalPan(bool f);
    virtual bool getFollowGlobalPan() const { return m_followPan; }

    virtual void setFollowGlobalZoom(bool f);
    virtual bool getFollowGlobalZoom() const { return m_followZoom; }

    virtual bool hasLightBackground() const;
    virtual QColor getForeground() const;
    virtual QColor getBackground() const;

    enum TextStyle {
	BoxedText,
	OutlinedText
    };

    virtual void drawVisibleText(QPainter &p, int x, int y,
				 QString text, TextStyle style) const;

    virtual void drawMeasurementRect(QPainter &p, const Layer *,
                                     QRect rect, bool focus) const;

    virtual bool shouldIlluminateLocalFeatures(const Layer *, QPoint &) const {
	return false;
    }
    virtual bool shouldIlluminateLocalSelection(QPoint &, bool &, bool &) const {
	return false;
    }

    virtual void setPlaybackFollow(PlaybackFollowMode m);
    virtual PlaybackFollowMode getPlaybackFollow() const { return m_followPlay; }

    typedef PropertyContainer::PropertyName PropertyName;

    // We implement the PropertyContainer API, although we don't
    // actually subclass PropertyContainer.  We have our own
    // PropertyContainer that we can return on request that just
    // delegates back to us.
    virtual PropertyContainer::PropertyList getProperties() const;
    virtual QString getPropertyLabel(const PropertyName &) const;
    virtual PropertyContainer::PropertyType getPropertyType(const PropertyName &) const;
    virtual int getPropertyRangeAndValue(const PropertyName &,
					 int *min, int *max, int *deflt) const;
    virtual QString getPropertyValueLabel(const PropertyName &,
					  int value) const;
    virtual void setProperty(const PropertyName &, int value);
    virtual QString getPropertyContainerName() const {
	return objectName();
    }
    virtual QString getPropertyContainerIconName() const = 0;

    virtual size_t getPropertyContainerCount() const;

    virtual const PropertyContainer *getPropertyContainer(size_t i) const;
    virtual PropertyContainer *getPropertyContainer(size_t i);

    // Render the contents on a wide canvas
    virtual QImage *toNewImage(size_t f0, size_t f1);
    virtual QImage *toNewImage();
    virtual QSize getImageSize(size_t f0, size_t f1);
    virtual QSize getImageSize();

    virtual int getTextLabelHeight(const Layer *layer, QPainter &) const;

    virtual bool getValueExtents(QString unit, float &min, float &max,
                                 bool &log) const;

    virtual void toXml(QTextStream &stream, QString indent = "",
                       QString extraAttributes = "") const;

    // First frame actually in model, to right of scale, if present
    virtual size_t getFirstVisibleFrame() const;
    virtual size_t getLastVisibleFrame() const;

    size_t getModelsStartFrame() const;
    size_t getModelsEndFrame() const;

    typedef std::set<Model *> ModelSet;
    ModelSet getModels();

    //!!!
    int getAlignedPlaybackFrame() const;

signals:
    void propertyContainerAdded(PropertyContainer *pc);
    void propertyContainerRemoved(PropertyContainer *pc);
    void propertyContainerPropertyChanged(PropertyContainer *pc);
    void propertyContainerPropertyRangeChanged(PropertyContainer *pc);
    void propertyContainerNameChanged(PropertyContainer *pc);
    void propertyContainerSelected(PropertyContainer *pc);
    void propertyChanged(PropertyContainer::PropertyName);

    void centreFrameChanged(unsigned long frame,
                            bool globalScroll,
                            PlaybackFollowMode followMode);

    void zoomLevelChanged(unsigned long, bool);

    void contextHelpChanged(const QString &);

public slots:
    virtual void modelChanged();
    virtual void modelChanged(size_t startFrame, size_t endFrame);
    virtual void modelCompletionChanged();
    virtual void modelReplaced();
    virtual void layerParametersChanged();
    virtual void layerParameterRangesChanged();
    virtual void layerMeasurementRectsChanged();
    virtual void layerNameChanged();

    virtual void globalCentreFrameChanged(unsigned long);
    virtual void viewCentreFrameChanged(View *, unsigned long);
    virtual void viewManagerPlaybackFrameChanged(unsigned long);
    virtual void viewZoomLevelChanged(View *, unsigned long, bool);

    virtual void propertyContainerSelected(View *, PropertyContainer *pc);

    virtual void selectionChanged();
    virtual void toolModeChanged();
    virtual void overlayModeChanged();
    virtual void zoomWheelsEnabledChanged();

protected:
    View(QWidget *, bool showProgress);
    virtual void paintEvent(QPaintEvent *e);
    virtual void drawSelections(QPainter &);
    virtual bool shouldLabelSelections() const { return true; }
    virtual bool render(QPainter &paint, int x0, size_t f0, size_t f1);

    typedef std::vector<Layer *> LayerList;

    int getModelsSampleRate() const;
    bool areLayersScrollable() const;
    LayerList getScrollableBackLayers(bool testChanged, bool &changed) const;
    LayerList getNonScrollableFrontLayers(bool testChanged, bool &changed) const;
    size_t getZoomConstraintBlockSize(size_t blockSize,
				      ZoomConstraint::RoundingDirection dir =
				      ZoomConstraint::RoundNearest) const;

    // True if the top layer(s) use colours for meaningful things.  If
    // this is the case, selections will be shown using unfilled boxes
    // rather than with a translucent fill.
    bool areLayerColoursSignificant() const;

    // True if the top layer has a time axis on the x coordinate (this
    // is generally the case except for spectrum/slice layers).  It
    // will not be possible to make or display selections if this is
    // false.
    bool hasTopLayerTimeXAxis() const;

    bool setCentreFrame(size_t f, bool doEmit);

    void checkProgress(void *object);

    size_t              m_centreFrame;
    int                 m_zoomLevel;
    bool                m_followPan;
    bool                m_followZoom;
    PlaybackFollowMode  m_followPlay;
    size_t              m_playPointerFrame;
    bool                m_lightBackground;
    bool                m_showProgress;

    QPixmap            *m_cache;
    size_t              m_cacheCentreFrame;
    int                 m_cacheZoomLevel;
    bool                m_selectionCached;

    bool                m_deleting;

    LayerList           m_layers; // I don't own these, but see dtor note above
    bool                m_haveSelectedLayer;

    // caches for use in getScrollableBackLayers, getNonScrollableFrontLayers
    mutable LayerList m_lastScrollableBackLayers;
    mutable LayerList m_lastNonScrollableBackLayers;

    class LayerProgressBar : public QProgressBar {
    public:
	LayerProgressBar(QWidget *parent);
	virtual QString text() const { return m_text; }
	virtual void setText(QString text) { m_text = text; }
    protected:
	QString m_text;
    };

    typedef std::map<Layer *, LayerProgressBar *> ProgressMap;
    ProgressMap m_progressBars; // I own the ProgressBars

    ViewManager *m_manager; // I don't own this
    ViewPropertyContainer *m_propertyContainer; // I own this
};


// Use this for delegation, because we can't subclass from
// PropertyContainer (which is a QObject) ourselves because of
// ambiguity with QFrame parent

class ViewPropertyContainer : public PropertyContainer
{
    Q_OBJECT

public:
    ViewPropertyContainer(View *v);
    PropertyList getProperties() const { return m_v->getProperties(); }
    QString getPropertyLabel(const PropertyName &n) const {
        return m_v->getPropertyLabel(n);
    }
    PropertyType getPropertyType(const PropertyName &n) const {
	return m_v->getPropertyType(n);
    }
    int getPropertyRangeAndValue(const PropertyName &n, int *min, int *max,
                                 int *deflt) const {
	return m_v->getPropertyRangeAndValue(n, min, max, deflt);
    }
    QString getPropertyValueLabel(const PropertyName &n, int value) const {
	return m_v->getPropertyValueLabel(n, value);
    }
    QString getPropertyContainerName() const {
	return m_v->getPropertyContainerName();
    }
    QString getPropertyContainerIconName() const {
	return m_v->getPropertyContainerIconName();
    }

public slots:
    virtual void setProperty(const PropertyName &n, int value) {
	m_v->setProperty(n, value);
    }

protected:
    View *m_v;
};

#endif