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diff --git a/src/labs/settings/qqmlsettings.cpp b/src/labs/settings/qqmlsettings.cpp
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+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#include "qqmlsettings_p.h"
+#include <qcoreevent.h>
+#include <qcoreapplication.h>
+#include <qloggingcategory.h>
+#include <qsettings.h>
+#include <qpointer.h>
+#include <qjsvalue.h>
+#include <qqmlinfo.h>
+#include <qdebug.h>
+#include <qhash.h>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \qmlmodule Qt.labs.settings 1.0
+    \title Qt Labs Settings QML Types
+    \ingroup qmlmodules
+    \deprecated [6.5] Use \l [QML] {QtCore::}{Settings} from Qt Qml Core instead.
+    \brief Provides persistent platform-independent application settings.
+
+    To use this module, import the module with the following line:
+
+    \code
+    import Qt.labs.settings
+    \endcode
+*/
+
+/*!
+    \qmltype Settings
+//!    \instantiates QQmlSettings
+    \inqmlmodule Qt.labs.settings
+    \ingroup settings
+    \deprecated [6.5] Use \l [QML] {QtCore::}{Settings} from Qt Qml Core instead.
+    \brief Provides persistent platform-independent application settings.
+
+    The Settings type provides persistent platform-independent application settings.
+
+    \note This type is made available by importing the \b Qt.labs.settings module.
+    \e {Types in the Qt.labs module are not guaranteed to remain compatible
+    in future versions.}
+
+    Users normally expect an application to remember its settings (window sizes
+    and positions, options, etc.) across sessions. The Settings type enables you
+    to save and restore such application settings with the minimum of effort.
+
+    Individual setting values are specified by declaring properties within a
+    Settings element. All \l {QML Value Types}{value type} properties are
+    supported. The recommended approach is to use property aliases in order
+    to get automatic property updates both ways. The following example shows
+    how to use Settings to store and restore the geometry of a window.
+
+    \qml
+    import QtQuick.Window
+    import Qt.labs.settings
+
+    Window {
+        id: window
+
+        width: 800
+        height: 600
+
+        Settings {
+            property alias x: window.x
+            property alias y: window.y
+            property alias width: window.width
+            property alias height: window.height
+        }
+    }
+    \endqml
+
+    At first application startup, the window gets default dimensions specified
+    as 800x600. Notice that no default position is specified - we let the window
+    manager handle that. Later when the window geometry changes, new values will
+    be automatically stored to the persistent settings. The second application
+    run will get initial values from the persistent settings, bringing the window
+    back to the previous position and size.
+
+    A fully declarative syntax, achieved by using property aliases, comes at the
+    cost of storing persistent settings whenever the values of aliased properties
+    change. Normal properties can be used to gain more fine-grained control over
+    storing the persistent settings. The following example illustrates how to save
+    a setting on component destruction.
+
+    \qml
+    import QtQuick
+    import Qt.labs.settings
+
+    Item {
+        id: page
+
+        state: settings.state
+
+        states: [
+            State {
+                name: "active"
+                // ...
+            },
+            State {
+                name: "inactive"
+                // ...
+            }
+        ]
+
+        Settings {
+            id: settings
+            property string state: "active"
+        }
+
+        Component.onDestruction: {
+            settings.state = page.state
+        }
+    }
+    \endqml
+
+    Notice how the default value is now specified in the persistent setting property,
+    and the actual property is bound to the setting in order to get the initial value
+    from the persistent settings.
+
+    \section1 Application Identifiers
+
+    Application specific settings are identified by providing application
+    \l {QCoreApplication::applicationName}{name},
+    \l {QCoreApplication::organizationName}{organization} and
+    \l {QCoreApplication::organizationDomain}{domain}, or by specifying
+    \l fileName.
+
+    \code
+    #include <QGuiApplication>
+    #include <QQmlApplicationEngine>
+
+    int main(int argc, char *argv[])
+    {
+        QGuiApplication app(argc, argv);
+        app.setOrganizationName("Some Company");
+        app.setOrganizationDomain("somecompany.com");
+        app.setApplicationName("Amazing Application");
+
+        QQmlApplicationEngine engine("main.qml");
+        return app.exec();
+    }
+    \endcode
+
+    These are typically specified in C++ in the beginning of \c main(),
+    but can also be controlled in QML via the following properties:
+    \list
+        \li \l {Qt::application}{Qt.application.name},
+        \li \l {Qt::application}{Qt.application.organization} and
+        \li \l {Qt::application}{Qt.application.domain}.
+    \endlist
+
+    \section1 Categories
+
+    Application settings may be divided into logical categories by specifying
+    a category name via the \l category property. Using logical categories not
+    only provides a cleaner settings structure, but also prevents possible
+    conflicts between setting keys.
+
+    If several categories are required, use several Settings objects, each with
+    their own category:
+
+    \qml
+    Item {
+        id: panel
+
+        visible: true
+
+        Settings {
+            category: "OutputPanel"
+            property alias visible: panel.visible
+            // ...
+        }
+
+        Settings {
+            category: "General"
+            property alias fontSize: fontSizeSpinBox.value
+            // ...
+        }
+    }
+    \endqml
+
+    Instead of ensuring that all settings in the application have unique names,
+    the settings can be divided into unique categories that may then contain
+    settings using the same names that are used in other categories - without
+    a conflict.
+
+    \section1 Notes
+
+    The current implementation is based on \l QSettings. This imposes certain
+    limitations, such as missing change notifications. Writing a setting value
+    using one instance of Settings does not update the value in another Settings
+    instance, even if they are referring to the same setting in the same category.
+
+    The information is stored in the system registry on Windows, and in XML
+    preferences files on \macos. On other Unix systems, in the absence of a
+    standard, INI text files are used. See \l QSettings documentation for
+    more details.
+
+    \sa {QtCore::}{Settings}, QSettings
+*/
+
+Q_LOGGING_CATEGORY(lcSettings, "qt.labs.settings")
+
+static const int settingsWriteDelay = 500;
+
+class QQmlSettingsPrivate
+{
+    Q_DECLARE_PUBLIC(QQmlSettings)
+
+public:
+    QQmlSettingsPrivate();
+
+    QSettings *instance() const;
+
+    void init();
+    void reset();
+
+    void load();
+    void store();
+
+    void _q_propertyChanged();
+    QVariant readProperty(const QMetaProperty &property) const;
+
+    QQmlSettings *q_ptr = nullptr;
+    int timerId = 0;
+    bool initialized = false;
+    QString category;
+    QString fileName;
+    mutable QPointer<QSettings> settings;
+    QHash<const char *, QVariant> changedProperties;
+};
+
+QQmlSettingsPrivate::QQmlSettingsPrivate() {}
+
+QSettings *QQmlSettingsPrivate::instance() const
+{
+    if (!settings) {
+        QQmlSettings *q = const_cast<QQmlSettings*>(q_func());
+        settings = fileName.isEmpty() ? new QSettings(q) : new QSettings(fileName, QSettings::IniFormat, q);
+        if (settings->status() != QSettings::NoError) {
+            // TODO: can't print out the enum due to the following error:
+            // error: C2666: 'QQmlInfo::operator <<': 15 overloads have similar conversions
+            qmlWarning(q) << "Failed to initialize QSettings instance. Status code is: " << int(settings->status());
+
+            if (settings->status() == QSettings::AccessError) {
+                QVector<QString> missingIdentifiers;
+                if (QCoreApplication::organizationName().isEmpty())
+                    missingIdentifiers.append(QLatin1String("organizationName"));
+                if (QCoreApplication::organizationDomain().isEmpty())
+                    missingIdentifiers.append(QLatin1String("organizationDomain"));
+                if (QCoreApplication::applicationName().isEmpty())
+                    missingIdentifiers.append(QLatin1String("applicationName"));
+
+                if (!missingIdentifiers.isEmpty())
+                    qmlWarning(q) << "The following application identifiers have not been set: " << missingIdentifiers;
+            }
+            return settings;
+        }
+
+        if (!category.isEmpty())
+            settings->beginGroup(category);
+        if (initialized)
+            q->d_func()->load();
+    }
+    return settings;
+}
+
+void QQmlSettingsPrivate::init()
+{
+    if (!initialized) {
+        qCDebug(lcSettings) << "QQmlSettings: stored at" << instance()->fileName();
+        load();
+        initialized = true;
+    }
+}
+
+void QQmlSettingsPrivate::reset()
+{
+    if (initialized && settings && !changedProperties.isEmpty())
+        store();
+    delete settings;
+}
+
+void QQmlSettingsPrivate::load()
+{
+    Q_Q(QQmlSettings);
+    const QMetaObject *mo = q->metaObject();
+    const int offset = mo->propertyOffset();
+    const int count = mo->propertyCount();
+
+    // don't save built-in properties if there aren't any qml properties
+    if (offset == 1)
+        return;
+
+    for (int i = offset; i < count; ++i) {
+        QMetaProperty property = mo->property(i);
+        const QString propertyName = QString::fromUtf8(property.name());
+
+        const QVariant previousValue = readProperty(property);
+        const QVariant currentValue = instance()->value(propertyName,
+                                                        previousValue);
+
+        if (!currentValue.isNull() && (!previousValue.isValid()
+                || (currentValue.canConvert(previousValue.metaType())
+                    && previousValue != currentValue))) {
+            property.write(q, currentValue);
+            qCDebug(lcSettings) << "QQmlSettings: load" << property.name() << "setting:" << currentValue << "default:" << previousValue;
+        }
+
+        // ensure that a non-existent setting gets written
+        // even if the property wouldn't change later
+        if (!instance()->contains(propertyName))
+            _q_propertyChanged();
+
+        // setup change notifications on first load
+        if (!initialized && property.hasNotifySignal()) {
+            static const int propertyChangedIndex = mo->indexOfSlot("_q_propertyChanged()");
+            QMetaObject::connect(q, property.notifySignalIndex(), q, propertyChangedIndex);
+        }
+    }
+}
+
+void QQmlSettingsPrivate::store()
+{
+    QHash<const char *, QVariant>::const_iterator it = changedProperties.constBegin();
+    while (it != changedProperties.constEnd()) {
+        instance()->setValue(QString::fromUtf8(it.key()), it.value());
+        qCDebug(lcSettings) << "QQmlSettings: store" << it.key() << ":" << it.value();
+        ++it;
+    }
+    changedProperties.clear();
+}
+
+void QQmlSettingsPrivate::_q_propertyChanged()
+{
+    Q_Q(QQmlSettings);
+    const QMetaObject *mo = q->metaObject();
+    const int offset = mo->propertyOffset();
+    const int count = mo->propertyCount();
+    for (int i = offset; i < count; ++i) {
+        const QMetaProperty &property = mo->property(i);
+        const QVariant value = readProperty(property);
+        changedProperties.insert(property.name(), value);
+        qCDebug(lcSettings) << "QQmlSettings: cache" << property.name() << ":" << value;
+    }
+    if (timerId != 0)
+        q->killTimer(timerId);
+    timerId = q->startTimer(settingsWriteDelay);
+}
+
+QVariant QQmlSettingsPrivate::readProperty(const QMetaProperty &property) const
+{
+    Q_Q(const QQmlSettings);
+    QVariant var = property.read(q);
+    if (var.metaType() == QMetaType::fromType<QJSValue>())
+        var = var.value<QJSValue>().toVariant();
+    return var;
+}
+
+QQmlSettings::QQmlSettings(QObject *parent)
+    : QObject(parent), d_ptr(new QQmlSettingsPrivate)
+{
+    Q_D(QQmlSettings);
+    d->q_ptr = this;
+}
+
+QQmlSettings::~QQmlSettings()
+{
+    Q_D(QQmlSettings);
+    d->reset(); // flush pending changes
+}
+
+/*!
+    \qmlproperty string Settings::category
+
+    This property holds the name of the settings category.
+
+    Categories can be used to group related settings together.
+*/
+QString QQmlSettings::category() const
+{
+    Q_D(const QQmlSettings);
+    return d->category;
+}
+
+void QQmlSettings::setCategory(const QString &category)
+{
+    Q_D(QQmlSettings);
+    if (d->category != category) {
+        d->reset();
+        d->category = category;
+        if (d->initialized)
+            d->load();
+    }
+}
+
+/*!
+    \qmlproperty string Settings::fileName
+
+    This property holds the path to the settings file. If the file doesn't
+    already exist, it is created.
+
+    \since Qt 5.12
+
+    \sa QSettings::fileName, QSettings::IniFormat
+*/
+QString QQmlSettings::fileName() const
+{
+    Q_D(const QQmlSettings);
+    return d->fileName;
+}
+
+void QQmlSettings::setFileName(const QString &fileName)
+{
+    Q_D(QQmlSettings);
+    if (d->fileName != fileName) {
+        d->reset();
+        d->fileName = fileName;
+        if (d->initialized)
+            d->load();
+    }
+}
+
+/*!
+   \qmlmethod var Settings::value(string key, var defaultValue)
+
+   Returns the value for setting \a key. If the setting doesn't exist,
+   returns \a defaultValue.
+
+   \since Qt 5.12
+
+   \sa QSettings::value
+*/
+QVariant QQmlSettings::value(const QString &key, const QVariant &defaultValue) const
+{
+    Q_D(const QQmlSettings);
+    return d->instance()->value(key, defaultValue);
+}
+
+/*!
+   \qmlmethod Settings::setValue(string key, var value)
+
+   Sets the value of setting \a key to \a value. If the key already exists,
+   the previous value is overwritten.
+
+   \since Qt 5.12
+
+   \sa QSettings::setValue
+*/
+void QQmlSettings::setValue(const QString &key, const QVariant &value)
+{
+    Q_D(const QQmlSettings);
+    d->instance()->setValue(key, value);
+    qCDebug(lcSettings) << "QQmlSettings: setValue" << key << ":" << value;
+}
+
+/*!
+   \qmlmethod Settings::sync()
+
+    Writes any unsaved changes to permanent storage, and reloads any
+    settings that have been changed in the meantime by another
+    application.
+
+    This function is called automatically from QSettings's destructor and
+    by the event loop at regular intervals, so you normally don't need to
+    call it yourself.
+
+   \sa QSettings::sync
+*/
+void QQmlSettings::sync()
+{
+    Q_D(QQmlSettings);
+    d->instance()->sync();
+}
+
+void QQmlSettings::classBegin()
+{
+}
+
+void QQmlSettings::componentComplete()
+{
+    Q_D(QQmlSettings);
+    d->init();
+    qmlWarning(this) << "The Settings type from Qt.labs.settings is deprecated"
+                        " and will be removed in a future release. Please use "
+                        "the one from QtCore instead.";
+}
+
+void QQmlSettings::timerEvent(QTimerEvent *event)
+{
+    Q_D(QQmlSettings);
+    if (event->timerId() == d->timerId) {
+        killTimer(d->timerId);
+        d->timerId = 0;
+
+        d->store();
+    }
+    QObject::timerEvent(event);
+}
+
+QT_END_NAMESPACE
+
+#include "moc_qqmlsettings_p.cpp"