QXmppDataFormBase.h

// SPDX-FileCopyrightText: 2021 Linus Jahn <lnj@kaidan.im>
//
// SPDX-License-Identifier: LGPL-2.1-or-later
 
#ifndef QXMPPDATAFORMBASED_H
#define QXMPPDATAFORMBASED_H
 
#include "QXmppDataForm.h"
 
#include <optional>
 
class QXmppDataForm;
 
class QXMPP_EXPORT QXmppDataFormBase
{
public:
    virtual QXmppDataForm toDataForm() const;
 
protected:
    static bool fromDataForm(const QXmppDataForm &form, QXmppDataFormBase &parent);
 
    virtual QString formType() const = 0;
    virtual void parseForm(const QXmppDataForm &) = 0;
    virtual void serializeForm(QXmppDataForm &) const = 0;
 
    std::optional<quint32> parseUInt(const QVariant &variant)
    {
        bool ok;
        if (const auto result = variant.toString().toUInt(&ok); ok) {
            return result;
        }
        return std::nullopt;
    }
 
    std::optional<quint64> parseULongLong(const QVariant &variant)
    {
        bool ok;
        if (const auto result = variant.toString().toULongLong(&ok); ok) {
            return result;
        }
        return std::nullopt;
    }
 
    std::optional<bool> parseBool(const QVariant &variant)
    {
#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
        if (variant.typeId() == QMetaType::Type::Bool) {
#else
        if (variant.type() == QVariant::Bool) {
#endif
            return variant.toBool();
#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
        } else if (variant.typeId() == QMetaType::Type::QString) {
#else
        } else if (variant.type() == QVariant::String) {
#endif
            auto string = variant.toString();
            if (string == u"1" || string == u"true") {
                return true;
            } else if (string == u"0" || string == u"false") {
                return false;
            }
        }
        return std::nullopt;
    }
 
    template<typename T>
    static void serializeValue(QXmppDataForm &form, QXmppDataForm::Field::Type type, const QString &name, const T &value)
    {
        form.appendField(QXmppDataForm::Field(type, name, value));
    }
 
    template<typename T>
    static void serializeNullable(QXmppDataForm &form, QXmppDataForm::Field::Type type, QStringView name, const T &value)
    {
        if (!value.isNull()) {
            serializeValue(form, type, name.toString(), value);
        }
    }
 
    template<typename T>
    static void serializeEmptyable(QXmppDataForm &form, QXmppDataForm::Field::Type type, QStringView name, const T &value)
    {
        if (!value.isEmpty()) {
            serializeValue(form, type, name.toString(), value);
        }
    }
 
    template<typename T, typename ValueConverter = T (*)(T)>
    static void serializeOptional(
        QXmppDataForm &form, QXmppDataForm::Field::Type type, QStringView name, const std::optional<T> &optional, ValueConverter convert = [](T a) { return a; })
    {
        if (optional.has_value()) {
            serializeValue(form, type, name.toString(), convert(*optional));
        }
    }
 
    template<typename T>
    static void serializeOptionalNumber(QXmppDataForm &form, QXmppDataForm::Field::Type type, QStringView name, std::optional<T> optional)
    {
        if (optional.has_value()) {
            serializeValue(form, type, name.toString(), QString::number(*optional));
        }
    }
 
    static void serializeDatetime(QXmppDataForm &form, const QString &name, const QDateTime &datetime, QXmppDataForm::Field::Type type = QXmppDataForm::Field::TextSingleField);
};
 
class QXmppExtensibleDataFormBasePrivate;
 
class QXMPP_EXPORT QXmppExtensibleDataFormBase : public QXmppDataFormBase
{
public:
    QXmppExtensibleDataFormBase();
    QXmppExtensibleDataFormBase(const QXmppExtensibleDataFormBase &);
    QXmppExtensibleDataFormBase(QXmppExtensibleDataFormBase &&);
    virtual ~QXmppExtensibleDataFormBase();
 
    QXmppExtensibleDataFormBase &operator=(const QXmppExtensibleDataFormBase &);
    QXmppExtensibleDataFormBase &operator=(QXmppExtensibleDataFormBase &&);
 
    QList<QXmppDataForm::Field> unknownFields() const;
    void setUnknownFields(const QList<QXmppDataForm::Field> &unknownFields);
 
protected:
    void parseForm(const QXmppDataForm &) override;
    void serializeForm(QXmppDataForm &) const override;
 
    virtual bool parseField(const QXmppDataForm::Field &);
 
private:
    QSharedDataPointer<QXmppExtensibleDataFormBasePrivate> d;
};
 
namespace QXmpp::Private {
 
template<typename T>
concept DataFormConvertible = requires(const QXmppDataForm &form) {
    { T::DataFormType };
    { T::fromDataForm(form) } -> std::same_as<std::optional<T>>;
};
 
template<DataFormConvertible T>
inline constexpr auto DataFormType = T::DataFormType;
 
}  // namespace QXmpp::Private
 
#endif  // QXMPPDATAFORMBASED_H