view transform/TransformFactory.h @ 76:af2725b5d6fe

* Implement harmonic cursor in spectrogram
* Implement layer export.  This doesn't quite do the right thing for the SV
  XML layer export yet -- it doesn't include layer display information, so
  when imported, it only creates an invisible model.  Could also do with
  fixing CSV file import so as to work correctly for note and text layers.

/* -*- 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 _TRANSFORM_FACTORY_H_
#define _TRANSFORM_FACTORY_H_

#include "Transform.h"

#include <map>

class TransformFactory : public QObject
{
    Q_OBJECT

public:
    virtual ~TransformFactory();

    static TransformFactory *instance();

    // The name is intended to be computer-referenceable, and unique
    // within the application.  The description is intended to be
    // human readable.  In principle it doesn't have to be unique, but
    // the factory will add suffixes to ensure that it is, all the
    // same (just to avoid user confusion).  The friendly name is a
    // shorter version of the description.  The type is also intended
    // to be user-readable, for use in menus.

    struct TransformDesc {
        TransformDesc() { }
	TransformDesc(QString _type, TransformName _name, QString _description,
                      QString _friendlyName, QString _maker,
                      QString _units, bool _configurable) :
	    type(_type), name(_name), description(_description),
            friendlyName(_friendlyName),
            maker(_maker), units(_units), configurable(_configurable) { }
        QString type;
	TransformName name;
	QString description;
        QString friendlyName;
        QString maker;
        QString units;
        bool configurable;
    };
    typedef std::vector<TransformDesc> TransformList;

    TransformList getAllTransforms();

    std::vector<QString> getAllTransformTypes();

    /**
     * Get a configuration XML string for the given transform (by
     * asking the user, most likely).  Returns true if the transform
     * is acceptable, false if the operation should be cancelled.
     */
    bool getConfigurationForTransform(TransformName name, Model *inputModel,
                                      int &channel,
                                      QString &configurationXml);

    /**
     * Return the output model resulting from applying the named
     * transform to the given input model.  The transform may still be
     * working in the background when the model is returned; check the
     * output model's isReady completion status for more details.
     *
     * If the transform is unknown or the input model is not an
     * appropriate type for the given transform, or if some other
     * problem occurs, return 0.
     * 
     * The returned model is owned by the caller and must be deleted
     * when no longer needed.
     */
    Model *transform(TransformName name, Model *inputModel,
                     int channel, QString configurationXml = "");

    /**
     * Full description of a transform, suitable for putting on a menu.
     */
    QString getTransformDescription(TransformName name);

    /**
     * Brief but friendly description of a transform, suitable for use
     * as the name of the output layer.
     */
    QString getTransformFriendlyName(TransformName name);

    QString getTransformUnits(TransformName name);

    /**
     * Return true if the transform has any configurable parameters,
     * i.e. if getConfigurationForTransform can ever return a non-trivial
     * (not equivalent to empty) configuration string.
     */
    bool isTransformConfigurable(TransformName name);

    /**
     * If the transform has a prescribed number or range of channel
     * inputs, return true and set minChannels and maxChannels to the
     * minimum and maximum number of channel inputs the transform can
     * accept.
     */
    bool getTransformChannelRange(TransformName name,
                                  int &minChannels, int &maxChannels);

    //!!! Need some way to indicate that the input model has changed /
    //been deleted so as not to blow up backgrounded transform!  -- Or
    //indeed, if the output model has been deleted -- could equally
    //well happen!

    //!!! Need transform category!
	
protected slots:
    void transformFinished();

protected:
    Transform *createTransform(TransformName name, Model *inputModel,
                               int channel, QString configurationXml, bool start);

    struct TransformIdent
    {
        TransformName name;
        QString configurationXml;
    };

    typedef std::map<TransformName, QString> TransformConfigurationMap;
    TransformConfigurationMap m_lastConfigurations;

    typedef std::map<TransformName, TransformDesc> TransformDescriptionMap;
    TransformDescriptionMap m_transforms;

    void populateTransforms();
    void populateFeatureExtractionPlugins(TransformDescriptionMap &);
    void populateRealTimePlugins(TransformDescriptionMap &);

    static TransformFactory *m_instance;
};


#endif