blame: src/imagemodel.h

#pragma once

#include <QAbstractListModel>

#include <QPixmap>

#include <QVector>

#include <QThreadPool>

#include <QSet>

#include <QHash>

#include <QList>

#include <atomic>

#include <QIcon>

class ThumbnailWorker;

class ImageModel : public QAbstractListModel

{

    Q_OBJECT

public:

    explicit ImageModel(QObject *parent = nullptr);

    ~ImageModel();

    void setDirectory(const QString &path);

    QString filePath(const QModelIndex &index) const;

    bool isFolder(const QModelIndex &index) const;

    QString currentDirectory() const;

    void requestThumbnails(int firstRow, int lastRow);

    void setCacheMaxSize(int n);

    int rowCount(const QModelIndex &parent = QModelIndex()) const override;

    QVariant data(const QModelIndex &index, int role) const override;

    void thumbnailReady(int row, const QImage &image);

private:

    struct Item

    {

        QString path;

        QString displayName;

        QPixmap thumbnail;

        bool loaded = false;

        bool isFolder = false;

    };

    void queueRow(int row);

    using ThumbnailMap = QHash<QString, QPixmap>;

    QVector<Item> m_items;

    QThreadPool m_threadPool;

    QPixmap m_placeholder;

    QSet<int> m_pendingRows;

    std::atomic_bool m_cancelFlag{false};

    QIcon m_folderIcon;

    QString m_currentDir;

    // Folder thumbnail cache (last N visited directories)

    QHash<QString, ThumbnailMap> m_folderThumbnailCache;

    QList<QString> m_cacheOrder;

    int m_cacheMaxSize = 4;

};