1 files changed, 175 insertions, 0 deletions
diff --git a/src/gui/platform/unix/qgnomeportalinterface.cpp b/src/gui/platform/unix/qgnomeportalinterface.cpp
new file mode 100644
index 00000000000..8528ed19328
--- /dev/null
+++ b/src/gui/platform/unix/qgnomeportalinterface.cpp
@@ -0,0 +1,175 @@
+// Copyright (C) 2025 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 "qgnomeportalinterface_p.h"
+#include "qdbussettings_p.h"
+#include <private/qdbusplatformmenu_p.h>
+#include <QtDBus/QDBusMessage>
+#include <QtDBus/QDBusPendingCall>
+#include <QtDBus/QDBusReply>
+#include <QtDBus/QDBusVariant>
+
+QT_BEGIN_NAMESPACE
+
+#if QT_CONFIG(dbus)
+Q_STATIC_LOGGING_CATEGORY(lcQpaThemeGnome, "qt.qpa.theme.gnome")
+#endif // QT_CONFIG(dbus)
+
+using namespace Qt::StringLiterals;
+
+QGnomePortalInterface::QGnomePortalInterface(QObject *parent)
+    : QObject(parent), m_dbus{ new QDBusListener }
+{
+    QObject::connect(m_dbus.get(), &QDBusListener::settingChanged, this,
+                     &QGnomePortalInterface::dbusSettingChanged);
+
+    querySettings();
+}
+
+/*!
+    \internal
+    \brief QGnomePortalInterface::colorScheme
+    This is a getter method for the color-scheme loaded from the DBus portal.
+    \param fallback indicates the fallback color-scheme.
+    \return returns the cached color-scheme. If the color-scheme was not loaded
+    it returns the \a fallback color-scheme.
+ */
+Qt::ColorScheme QGnomePortalInterface::colorScheme(Qt::ColorScheme fallback) const
+{
+    if (!m_colorScheme.has_value())
+        return fallback;
+    return m_colorScheme.value();
+}
+
+/*!
+    \internal
+    \brief QGnomePortalInterface::contrastPreference
+    This is a getter method for the contrast-preference loaded from the DBus portal.
+    \param fallback indicates the fallback contrast-preference.
+    \return returns the cached contrast-preference if it was loaded. Otherwise,
+    returns the \a fallback contrast-preference.
+ */
+Qt::ContrastPreference
+QGnomePortalInterface::contrastPreference(Qt::ContrastPreference fallback) const
+{
+    if (!m_contrast.has_value())
+        return fallback;
+    return m_contrast.value();
+}
+
+void QGnomePortalInterface::querySettings()
+{
+    QDBusConnection dbus = QDBusConnection::sessionBus();
+    if (!dbus.isConnected()) {
+        qCWarning(lcQpaThemeGnome) << "dbus connection failed. Last error: " << dbus.lastError();
+        return;
+    }
+
+    constexpr auto method = "ReadAll"_L1;
+    auto message = QDBusMessage::createMethodCall(s_service, s_path, s_interface, method);
+
+    message << QStringList{ QDBusSettings::XdgSettings::AppearanceNamespace,
+                            QDBusSettings::GnomeSettings::AllyNamespace };
+
+    QDBusPendingCall pendingCall = dbus.asyncCall(message);
+    QDBusPendingCallWatcher *watcher = new QDBusPendingCallWatcher(pendingCall, this);
+
+    auto onWatcherFinished = [&](QDBusPendingCallWatcher *watcher) {
+        const QDBusMessage reply = watcher->reply();
+        if (QDBusMessage::ErrorMessage == reply.type()) {
+            qCWarning(lcQpaThemeGnome)
+                    << "dbus reply error: [" << reply.errorName() << "]" << reply.errorMessage();
+            watcher->deleteLater();
+            return;
+        }
+
+        const auto convertXdgColorScheme = [](const QVariant &value) {
+            using namespace QDBusSettings::XdgSettings;
+            return QVariant::fromValue(convertColorScheme(value));
+        };
+
+        constexpr auto XdgContrastKey = QDBusSettings::XdgSettings::ContrastKey;
+        const auto convertXdgContrast = [](const QVariant &value) {
+            using namespace QDBusSettings::XdgSettings;
+            return QVariant::fromValue(convertContrastPreference(value));
+        };
+
+        constexpr auto GnomeContrastKey = QDBusSettings::GnomeSettings::ContrastKey;
+        const auto convrtGnomeContrast = [](const QVariant &value) {
+            using namespace QDBusSettings::GnomeSettings;
+            return QVariant::fromValue(convertContrastPreference(value));
+        };
+
+        const QVariantList &args = reply.arguments();
+        for (const QVariant &arg_ : args) {
+            const QMap<QString, QVariantMap> arg = qdbus_cast<QMap<QString, QVariantMap>>(arg_);
+            for (auto aIt = arg.begin(); aIt != arg.end(); ++aIt) {
+                const QString &namespace_ = aIt.key();
+                const QVariantMap &settings = aIt.value();
+                for (auto sIt = settings.begin(); sIt != settings.end(); ++sIt) {
+                    const QString &key = sIt.key();
+                    const QVariant &value = sIt.value();
+                    if ((key == QDBusSettings::XdgSettings::ColorSchemeKey)
+                        && (namespace_ == QDBusSettings::XdgSettings::AppearanceNamespace))
+                        dbusSettingChanged(QDBusListener::Provider::Gnome,
+                                           QDBusListener::Setting::ColorScheme,
+                                           convertXdgColorScheme(value));
+                    else if ((key == XdgContrastKey)
+                             && (namespace_ == QDBusSettings::XdgSettings::AppearanceNamespace))
+                        dbusSettingChanged(QDBusListener::Provider::Gnome,
+                                           QDBusListener::Setting::Contrast,
+                                           convertXdgContrast(value));
+                    else if ((key == GnomeContrastKey)
+                             && (namespace_ == QDBusSettings::GnomeSettings::AllyNamespace))
+                        dbusSettingChanged(QDBusListener::Provider::Gnome,
+                                           QDBusListener::Setting::Contrast,
+                                           convrtGnomeContrast(value));
+                }
+            }
+        }
+        watcher->deleteLater();
+    };
+    connect(watcher, &QDBusPendingCallWatcher::finished, this, onWatcherFinished);
+}
+
+void QGnomePortalInterface::updateColorScheme(Qt::ColorScheme colorScheme)
+{
+    if (m_colorScheme.has_value() && (m_colorScheme.value() == colorScheme))
+        return;
+    m_colorScheme = colorScheme;
+    emit colorSchemeChanged(colorScheme);
+}
+
+void QGnomePortalInterface::updateContrast(Qt::ContrastPreference contrast)
+{
+    if (m_contrast.has_value() && (m_contrast.value() == contrast))
+        return;
+    m_contrast = contrast;
+    emit contrastChanged(contrast);
+}
+
+void QGnomePortalInterface::dbusSettingChanged(QDBusListener::Provider provider,
+                                               QDBusListener::Setting setting,
+                                               const QVariant &value)
+{
+    if (provider != QDBusListener::Provider::Gnome && provider != QDBusListener::Provider::Gtk)
+        return;
+
+    switch (setting) {
+    case QDBusListener::Setting::ColorScheme:
+        updateColorScheme(value.value<Qt::ColorScheme>());
+        break;
+    case QDBusListener::Setting::Contrast:
+        updateContrast(value.value<Qt::ContrastPreference>());
+        break;
+    case QDBusListener::Setting::Theme:
+        emit themeNameChanged(value.toString());
+        break;
+    default:
+        break;
+    }
+}
+
+QT_END_NAMESPACE
+
+#include "moc_qgnomeportalinterface_p.cpp"