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** Alternatively, this file may be used under the terms of the GNU Lesser
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#ifndef QJSONVALUE_H
#define QJSONVALUE_H

#include <QtCore/qglobal.h>
#include <QtCore/qstring.h>

QT_BEGIN_NAMESPACE

class QDebug;
class QVariant;
class QJsonArray;
class QJsonObject;

namespace QJsonPrivate {
    class Data;
    class Base;
    class Object;
    class Header;
    class Array;
    class Value;
    class Entry;
}

class Q_CORE_EXPORT QJsonValue
{
public:
    enum Type {
        Null =  0x0,
        Bool = 0x1,
        Double = 0x2,
        String = 0x3,
        Array = 0x4,
        Object = 0x5,
        Undefined = 0x80
    };

    QJsonValue(Type = Null);
    QJsonValue(bool b);
    QJsonValue(double n);
    QJsonValue(int n);
    QJsonValue(qint64 n);
    QJsonValue(const QString &s);
    QJsonValue(QLatin1String s);
#ifndef QT_NO_CAST_FROM_ASCII
    inline QT_ASCII_CAST_WARN QJsonValue(const char *s)
        : d(nullptr), t(String) { stringDataFromQStringHelper(QString::fromUtf8(s)); }
#endif
    QJsonValue(const QJsonArray &a);
    QJsonValue(const QJsonObject &o);

    ~QJsonValue();

    QJsonValue(const QJsonValue &other);
    QJsonValue &operator =(const QJsonValue &other);

    QJsonValue(QJsonValue &&other) noexcept
        : ui(other.ui),
          d(other.d),
          t(other.t)
    {
        other.ui = 0;
        other.d = nullptr;
        other.t = Null;
    }

    QJsonValue &operator =(QJsonValue &&other) noexcept
    {
        swap(other);
        return *this;
    }

    void swap(QJsonValue &other) noexcept
    {
        qSwap(ui, other.ui);
        qSwap(d, other.d);
        qSwap(t, other.t);
    }

    static QJsonValue fromVariant(const QVariant &variant);
    QVariant toVariant() const;

    Type type() const;
    inline bool isNull() const { return type() == Null; }
    inline bool isBool() const { return type() == Bool; }
    inline bool isDouble() const { return type() == Double; }
    inline bool isString() const { return type() == String; }
    inline bool isArray() const { return type() == Array; }
    inline bool isObject() const { return type() == Object; }
    inline bool isUndefined() const { return type() == Undefined; }

    bool toBool(bool defaultValue = false) const;
    int toInt(int defaultValue = 0) const;
    double toDouble(double defaultValue = 0) const;
    QString toString() const;
    QString toString(const QString &defaultValue) const;
    QJsonArray toArray() const;
    QJsonArray toArray(const QJsonArray &defaultValue) const;
    QJsonObject toObject() const;
    QJsonObject toObject(const QJsonObject &defaultValue) const;

#if QT_STRINGVIEW_LEVEL < 2
    const QJsonValue operator[](const QString &key) const;
#endif
    const QJsonValue operator[](QStringView key) const;
    const QJsonValue operator[](QLatin1String key) const;
    const QJsonValue operator[](int i) const;

    bool operator==(const QJsonValue &other) const;
    bool operator!=(const QJsonValue &other) const;

private:
    // avoid implicit conversions from char * to bool
    inline QJsonValue(const void *) {}
    friend class QJsonPrivate::Value;
    friend class QJsonArray;
    friend class QJsonObject;
    friend class QCborValue;
    friend Q_CORE_EXPORT QDebug operator<<(QDebug, const QJsonValue &);
    friend Q_CORE_EXPORT QDataStream &operator<<(QDataStream &, const QJsonValue &);

    QJsonValue(QJsonPrivate::Data *d, QJsonPrivate::Base *b, const QJsonPrivate::Value& v);
    void stringDataFromQStringHelper(const QString &string);

    void detach();

    union {
        quint64 ui;
        bool b;
        double dbl;
        QStringData *stringData;
        QJsonPrivate::Base *base;
    };
    QJsonPrivate::Data *d; // needed for Objects and Arrays
    Type t;
};

class Q_CORE_EXPORT QJsonValueRef
{
public:
    QJsonValueRef(QJsonArray *array, int idx)
        : a(array), is_object(false), index(static_cast<uint>(idx)) {}
    QJsonValueRef(QJsonObject *object, int idx)
        : o(object), is_object(true), index(static_cast<uint>(idx)) {}

    inline operator QJsonValue() const { return toValue(); }
    QJsonValueRef &operator = (const QJsonValue &val);
    QJsonValueRef &operator = (const QJsonValueRef &val);

    QVariant toVariant() const;
    inline QJsonValue::Type type() const { return toValue().type(); }
    inline bool isNull() const { return type() == QJsonValue::Null; }
    inline bool isBool() const { return type() == QJsonValue::Bool; }
    inline bool isDouble() const { return type() == QJsonValue::Double; }
    inline bool isString() const { return type() == QJsonValue::String; }
    inline bool isArray() const { return type() == QJsonValue::Array; }
    inline bool isObject() const { return type() == QJsonValue::Object; }
    inline bool isUndefined() const { return type() == QJsonValue::Undefined; }

    inline bool toBool() const { return toValue().toBool(); }
    inline int toInt() const { return toValue().toInt(); }
    inline double toDouble() const { return toValue().toDouble(); }
    inline QString toString() const { return toValue().toString(); }
    QJsonArray toArray() const;
    QJsonObject toObject() const;

    // ### Qt 6: Add default values
    inline bool toBool(bool defaultValue) const { return toValue().toBool(defaultValue); }
    inline int toInt(int defaultValue) const { return toValue().toInt(defaultValue); }
    inline double toDouble(double defaultValue) const { return toValue().toDouble(defaultValue); }
    inline QString toString(const QString &defaultValue) const { return toValue().toString(defaultValue); }

    inline bool operator==(const QJsonValue &other) const { return toValue() == other; }
    inline bool operator!=(const QJsonValue &other) const { return toValue() != other; }

private:
    QJsonValue toValue() const;

    union {
        QJsonArray *a;
        QJsonObject *o;
    };
    uint is_object : 1;
    uint index : 31;
};

// ### Qt 6: Get rid of these fake pointer classes
class QJsonValuePtr
{
    QJsonValue value;
public:
    explicit QJsonValuePtr(const QJsonValue& val)
        : value(val) {}

    QJsonValue& operator*() { return value; }
    QJsonValue* operator->() { return &value; }
};

class QJsonValueRefPtr
{
    QJsonValueRef valueRef;
public:
    QJsonValueRefPtr(QJsonArray *array, int idx)
        : valueRef(array, idx) {}
    QJsonValueRefPtr(QJsonObject *object, int idx)
        : valueRef(object, idx)  {}

    QJsonValueRef& operator*() { return valueRef; }
    QJsonValueRef* operator->() { return &valueRef; }
};

Q_DECLARE_SHARED_NOT_MOVABLE_UNTIL_QT6(QJsonValue)

Q_CORE_EXPORT uint qHash(const QJsonValue &value, uint seed = 0);

#if !defined(QT_NO_DEBUG_STREAM) && !defined(QT_JSON_READONLY)
Q_CORE_EXPORT QDebug operator<<(QDebug, const QJsonValue &);
#endif

#ifndef QT_NO_DATASTREAM
Q_CORE_EXPORT QDataStream &operator<<(QDataStream &, const QJsonValue &);
Q_CORE_EXPORT QDataStream &operator>>(QDataStream &, QJsonValue &);
#endif

QT_END_NAMESPACE

#endif // QJSONVALUE_H