thumbnailloadthread.h

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/* ============================================================
 *
 * This file is a part of digiKam project
 * https://www.digikam.org
 *
 * Date        : 2007-06-05
 * Description : Thumbnail loading
 *
 * Copyright (C) 2006-2011 by Marcel Wiesweg <marcel dot wiesweg at gmx dot de>
 * Copyright (C) 2008-2022 by Gilles Caulier <caulier dot gilles at gmail dot com>
 *
 * 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, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * ============================================================ */
 
#ifndef DIGIKAM_THUMB_NAIL_LOAD_THREAD_H
#define DIGIKAM_THUMB_NAIL_LOAD_THREAD_H
 
// Qt includes
 
#include <QPixmap>
#include <QImage>
 
// Local includes
 
#include "managedloadsavethread.h"
#include "thumbnailinfo.h"
 
namespace Digikam
{
 
class DbEngineParameters;
class ThumbnailCreator;
class ThumbnailInfoProvider;
 
class DIGIKAM_EXPORT ThumbnailLoadThread : public ManagedLoadSaveThread
{
    Q_OBJECT
 
public:
 
    explicit ThumbnailLoadThread(QObject* const parent = nullptr);
    ~ThumbnailLoadThread() override;
 
    static ThumbnailLoadThread* defaultThread();
    static ThumbnailLoadThread* defaultIconViewThread();
 
    static void cleanUp();
 
    static void initializeThumbnailDatabase(const DbEngineParameters& params, ThumbnailInfoProvider* const provider = nullptr);
 
    static void setDisplayingWidget(QWidget* const widget);
 
    bool find(const ThumbnailIdentifier& identifier, QPixmap& pixmap);
 
    bool find(const ThumbnailIdentifier& identifier, QPixmap& pixmap, int size);
 
    void find(const ThumbnailIdentifier& identifier);
 
    void find(const ThumbnailIdentifier& identifier, int size);
 
    void findGroup(QList<ThumbnailIdentifier>& identifiers);
    void findGroup(QList<ThumbnailIdentifier>& identifiers, int size);
 
    bool find(const ThumbnailIdentifier& identifier, const QRect& rect, QPixmap& pixmap);
    bool find(const ThumbnailIdentifier& identifier, const QRect& rect, QPixmap& pixmap, int size);
    void find(const ThumbnailIdentifier& identifier, const QRect& rect);
    void find(const ThumbnailIdentifier& identifier, const QRect& rect, int size);
    void findGroup(const QList<QPair<ThumbnailIdentifier, QRect> >& filePathAndRects);
    void findGroup(const QList<QPair<ThumbnailIdentifier, QRect> >& filePathsAndRects, int size);
 
    void preload(const ThumbnailIdentifier& identifier);
    void preload(const ThumbnailIdentifier& identifier, int size);
    void preloadGroup(QList<ThumbnailIdentifier>& identifiers);
    void preloadGroup(QList<ThumbnailIdentifier>& identifiers, int size);
 
    void pregenerateGroup(const QList<ThumbnailIdentifier>& identifiers);
    void pregenerateGroup(const QList<ThumbnailIdentifier>& identifiers, int size);
 
    void load(const LoadingDescription& description);
 
    QList<LoadingDescription> lastDescriptions() const;
 
    void setThumbnailSize(int size, bool forFace = false);
 
    static int maximumThumbnailSize();
    static int maximumThumbnailPixmapSize(bool withHighlighting);
 
    void setPixmapRequested(bool wantPixmap);
 
    void setHighlightPixmap(bool highlight);
 
    int        thumbnailToPixmapSize(int size) const;
    static int thumbnailToPixmapSize(bool withHighlight, int size);
 
    int pixmapToThumbnailSize(int size) const;
 
    void setSendSurrogatePixmap(bool send);
 
    void storeDetailThumbnail(const QString& filePath,
                              const QRect& detailRect,
                              const QImage& image,
                              bool isFace = false);
    int  storedSize() const;
 
    static void deleteThumbnail(const QString& filePath);
 
Q_SIGNALS:
 
    void signalThumbnailLoaded(const LoadingDescription& loadingDescription, const QPixmap& pix);
 
public:
 
    ThumbnailCreator* thumbnailCreator() const;
 
protected:
 
    void thumbnailLoaded(const LoadingDescription& loadingDescription, const QImage& img) override;
 
private:
 
    bool find(const ThumbnailIdentifier& identifier, int size, QPixmap* retPixmap, bool emitSignal, const QRect& detailRect);
    void load(const LoadingDescription& description, bool pregenerate);
    bool checkSize(int size);
    QPixmap surrogatePixmap(const LoadingDescription& loadingDescription);
 
Q_SIGNALS:
 
    void thumbnailsAvailable();
    void ThumbnailLoaded(const LoadingDescription&, const QImage&);
 
private Q_SLOTS:
 
    void slotThumbnailsAvailable();
    void slotThumbnailLoaded(const LoadingDescription&, const QImage&);
 
private:
 
    // Disable
    ThumbnailLoadThread(const ThumbnailLoadThread&)            = delete;
    ThumbnailLoadThread& operator=(const ThumbnailLoadThread&) = delete;
 
private:
 
    class Private;
    Private* const d;
};
 
// --------------------------------------------------------------------------------------------------
 
class DIGIKAM_EXPORT ThumbnailImageCatcher : public QObject
{
    Q_OBJECT
 
public:
 
    explicit ThumbnailImageCatcher(QObject* const parent = nullptr);
    explicit ThumbnailImageCatcher(ThumbnailLoadThread* const thread,
                                   QObject* const parent = nullptr);
    ~ThumbnailImageCatcher() override;
 
    ThumbnailLoadThread* thread() const;
    void setThumbnailLoadThread(ThumbnailLoadThread* const thread);
 
    int           enqueue();
    QList<QImage> waitForThumbnails();
 
public Q_SLOTS:
 
    void setActive(bool active);
 
    void cancel();
 
protected Q_SLOTS:
 
    void slotThumbnailLoaded(const LoadingDescription&, const QImage&);
 
private:
 
    // Disable
    ThumbnailImageCatcher(const ThumbnailImageCatcher&)            = delete;
    ThumbnailImageCatcher& operator=(const ThumbnailImageCatcher&) = delete;
 
private:
 
    class Private;
    Private* const d;
};
 
} // namespace Digikam
 
#endif // DIGIKAM_THUMB_NAIL_LOAD_THREAD_H