scimagecacheproxy.h

/*
For general Scribus (>=1.3.2) copyright and licensing information please refer
to the COPYING file provided with the program. Following this notice may exist
a copyright and/or license notice that predates the release of Scribus 1.3.2
for which a new license (GPL+exception) is in place.
*/
/***************************************************************************
    copyright            : (C) 2010 by Marcus Holland-Moritz
    email                : scribus@mhxnet.de
***************************************************************************/

/***************************************************************************
*                                                                         *
*   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.                                   *
*                                                                         *
***************************************************************************/

#ifndef SCIMAGECACHEPROXY_H
#define SCIMAGECACHEPROXY_H

#include "scconfig.h"
#include "scribusapi.h"

#include <QImage>
#include <QString>
#include <QMap>

class ScImage;
class ScLockedFile;
class ScImageCacheManager;

class SCRIBUS_API ScImageCacheProxy
{
public:
    static const QString metaSuffix;         
    static const QString referenceSuffix;    
    static const QString imageSuffix;        

    ScImageCacheProxy(const QString & fn);
    ~ScImageCacheProxy();

    bool enabled() const { return m_isEnabled; }
    const QString & getFilename() const { return m_filename; }
    bool load(QImage & image);
    bool save(const QImage & image);
    bool touch() const;
    void addMetadata(const QString & key, const QString & value);
    void addModifier(const QString & key, const QString & value);
    void delModifier(const QString & key);
    bool canUseCachedImage() const;

    void addInfo(const QString & key, const QString & value);
    QString getInfo(const QString & key) const;

    static QString getBaseName(const QString & metafile);
    static bool getRefCount(const QString & reffile, int & refcount);
    static bool fixRefCount(const QString & reffile, int refcount);
    static bool removeCacheEntry(const QString & metafile, bool haveMasterLock = false);

private:
    // Don't turn this into a QHash, element order is important
    typedef QMap<QString, QString> MetaMap;

    const QString m_filename;
    const bool m_isEnabled;
    mutable QString m_metanameCache;
    MetaMap m_metadata;
    MetaMap m_modifier;
    MetaMap m_imginfo;

    static QString imageFile(const QString & base);
    static QString referenceFile(const QString & base);

    static bool createCacheDir();
    static QString addDirLevels(QString name);

    const QString & metaName() const;
    QString imageBaseName(const QImage & image) const;

    bool loadMetadata(MetaMap *meta, MetaMap *mod, MetaMap *info, QString *base) const;

    static bool loadMetadata(ScLockedFile *file, MetaMap *meta, MetaMap *mod, MetaMap *info, QString *base);
    static bool loadMetadata(const QString & fn, MetaMap *meta, MetaMap *mod, MetaMap *info, QString *base);
    static void saveMetadata(ScLockedFile *file, const MetaMap & map, const MetaMap & mod, const MetaMap & info, const QString & base);

    static bool getRefCountAbs(const QString & reffile, int & refcount);
    static bool loadRef(ScLockedFile *file, int & refcount);
    static void saveRef(ScLockedFile *file, int refcount);
    static bool refImage(ScLockedFile *file);
    static bool unrefImage(ScLockedFile *file, const QString & imageName);
};

#endif