Применение Q_GADGET в C++&QtQuick

class Film
{
    Q_GADGET

    Q_PROPERTY(quint64 id READ id)
    Q_PROPERTY(QString endName  READ engName CONSTANT FINAL)
    Q_PROPERTY(QString rusName  READ rusName CONSTANT FINAL)
    Q_PROPERTY(QUrl coverUrl READ coverUrl CONSTANT FINAL)
    Q_PROPERTY(QUrl coverMaxiURL READ coverMaxiURL CONSTANT FINAL)
    Q_PROPERTY(QStringList screenshotsURL READ screenshotsURL CONSTANT FINAL)
    Q_PROPERTY(QString duration READ duration CONSTANT FINAL)
    Q_PROPERTY(QString description READ description CONSTANT FINAL)
    Q_PROPERTY(quint32 year READ year CONSTANT FINAL)
    Q_PROPERTY(QString countries READ countries CONSTANT FINAL)
    Q_PROPERTY(QString actors READ actors CONSTANT FINAL)
    Q_PROPERTY(QString genres READ genres CONSTANT FINAL)
    Q_PROPERTY(bool isValid READ isValid CONSTANT FINAL)

public:

    typedef QList<QUrl> Urls;

    Film();
    Film(Film&& obj);
    Film(const Film& obj) = default;

    static Film formJson(const QJsonObject& obj);

    quint64  id() const noexcept ;
    const QString& engName() const noexcept;
    const QString& rusName() const noexcept;

    const QUrl& coverUrl() const noexcept;
    const QUrl& coverMaxiURL() const noexcept;

    const QStringList& screenshotsURL() const noexcept;
    const QString& duration() const noexcept;

    const QString& description() const noexcept;

    quint32 year() const noexcept;

    const QString& countries() const noexcept;
    const QString& actors() const noexcept;
    const QString& genres() const noexcept;

    bool isValid() const noexcept;
    bool operator==(const Film& film) const noexcept;

private:

    struct FilmImpl;
    std::shared_ptr<FilmImpl> m_impl;
};

#include <QtCore/QDebug>
#include <QtCore/QVariant>
#include <QtCore/QJsonArray>
#include <QtCore/QJsonObject>

#include "Film.h"

struct Film::FilmImpl
{
    bool m_isValid = false;
    quint64 m_id   = 0;

    QString m_engName;
    QString m_russName;
    QUrl m_coverURL;
    QUrl m_coverMaxiURL;
    QStringList m_screenshotsURL;
    QString m_duration;
    QString m_description;
    QString countries;
    QString actors;
    QString genres;
    quint32 year;
};

Film::Film()
    : m_impl(std::make_shared<FilmImpl>())
{

}

Film::Film(Film&& obj):
    m_impl(std::move(obj.m_impl))
{
}

quint64 Film::id() const noexcept
{
    return m_impl->m_id;
}

const QStringList& Film::screenshotsURL() const noexcept
{
    return m_impl->m_screenshotsURL;
}

const QString& Film::rusName() const noexcept
{
    return m_impl->m_russName;
}

const QString& Film::engName() const noexcept
{
    return m_impl->m_engName;
}

const QUrl& Film::coverUrl() const noexcept
{
    return m_impl->m_coverURL;
}

const QUrl& Film::coverMaxiURL() const noexcept
{
    return m_impl->m_coverMaxiURL;
}
bool Film::isValid() const noexcept
{
    return m_impl->m_isValid;
}

const QString& Film::duration() const noexcept
{
    return m_impl->m_duration;
}

const QString& Film::description() const noexcept
{
    return m_impl->m_description;
}

bool Film::operator==(const Film& film) const noexcept
{
    return m_impl->m_id == film.m_impl->m_id;
}

Film Film::formJson(const QJsonObject &obj)
{
    Film film;
    film.m_impl->m_isValid      = true;
    film.m_impl->m_id           = obj.value("id").toVariant().toULongLong();
    film.m_impl->m_russName     = obj.value("rusName").toString();
    film.m_impl->m_engName      = obj.value("engName").toString();
    film.m_impl->m_description  = obj.value("description").toString();
    film.m_impl->countries      = obj.value("countries").toString();

    film.m_impl->m_coverURL     = QUrl(obj.value("coverURL").toString());
    film.m_impl->m_coverMaxiURL = QUrl(obj.value("coverMaxiURL").toString());
    film.m_impl->m_duration     = obj.value("duration").toString();

    film.m_impl->year           = obj.value("releaseYear").toVariant().toUInt();
    film.m_impl->actors         = obj.value("actors").toString();
    film.m_impl->genres         = obj.value("genres").toString();

    for(const auto& val : obj.value("screenshotsURL").toArray())
    {
        film.m_impl->m_screenshotsURL.push_back(val.toString());
    }

    return film;
}
quint32 Film::year() const noexcept
{
    return m_impl->year;
}
const QString& Film::countries() const noexcept
{
    return m_impl->countries;
}

const QString& Film::actors() const noexcept
{
    return m_impl->actors;
}

const QString& Film::genres() const noexcept
{
    return m_impl->genres;
}