// Copyright (c) 2020, The Monero Project
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#include <QImage>

#include <png.h>

struct quirc;

class QrDecoder
{
public:
    QrDecoder(const QrDecoder &) = delete;
    QrDecoder &operator=(const QrDecoder &) = delete;

    QrDecoder();
    ~QrDecoder();

    std::vector<std::string> decode(const QImage &image);
    std::vector<std::string> decodePNG(QString pngPath);

private:
    /* Dump decoded information on stdout. */
    void dump_data(const struct quirc_data *data);

    /* Dump a grid cell map on stdout. */
    void dump_cells(const struct quirc_code *code);

    /* Check if a file is a PNG image.
     *
     * returns 1 if the given file is a PNG and 0 otherwise.
     */
    int check_if_png(const char *filename);

    /* Read a PNG image into the decoder.
     *
     * Note that you must call quirc_end() if the function returns
     * successfully (0).
     */
    int load_png(struct quirc *q, const char *filename);

private:
    std::vector<std::string> decodeGrayscale8(const QImage &image);

private:
    quirc *m_qr;
};