+const int VERSION = 1; /// Settings version for backwords/forwards incompatible changes
+
+// This is used if no VersionMinor key exists, e.g. upgrading from a Quassel version before this
+// change. This shouldn't be increased from 1; instead, change the logic in Core::Core() and
+// QtUiApplication::init() to handle upgrading and downgrading.
+const int VERSION_MINOR_INITIAL = 1; /// Initial settings version for compatible changes
+
+QHash<QString, QVariant> Settings::_settingsCache;
+QHash<QString, bool> Settings::_settingsKeyPersistedCache;
+QHash<QString, std::shared_ptr<SettingsChangeNotifier>> Settings::_settingsChangeNotifier;
+
+#ifdef Q_OS_MAC
+# define create_qsettings QSettings s(QCoreApplication::organizationDomain(), _appName)
+#else
+# define create_qsettings QSettings s(fileName(), format())
+#endif
+
+Settings::Settings(QString group, QString appName)
+ : _group(std::move(group))
+ , _appName(std::move(appName))
+{}
+
+void Settings::setGroup(QString group)
+{
+ _group = std::move(group);
+}
+
+QString Settings::keyForNotify(const QString& key) const
+{
+ return key;
+}
+
+uint Settings::version() const
+{
+ // we don't cache this value, and we ignore the group
+ create_qsettings;
+ uint ver = s.value("Config/Version", 0).toUInt();
+ if (!ver) {
+ // No version, so create one
+ s.setValue("Config/Version", VERSION);
+ return VERSION;
+ }
+ return ver;
+}
+
+uint Settings::versionMinor() const
+{
+ // Don't cache this value; ignore the group
+ create_qsettings;
+ // '0' means new configuration, anything else indicates an existing configuration. Application
+ // initialization should check this value and manage upgrades/downgrades, e.g. in Core::Core()
+ // and QtUiApplication::init().
+ uint verMinor = s.value("Config/VersionMinor", 0).toUInt();
+
+ // As previous Quassel versions didn't implement this, we need to check if any settings other
+ // than Config/Version exist. If so, assume it's version 1.
+ if (verMinor == 0 && s.allKeys().count() > 1) {
+ // More than 1 key exists, but version's never been set. Assume and set version 1.
+ // const_cast is ok, because setVersionMinor() doesn't actually change this instance
+ const_cast<Settings*>(this)->setVersionMinor(VERSION_MINOR_INITIAL);
+ return VERSION_MINOR_INITIAL;
+ }
+ else {
+ return verMinor;
+ }
+}
+
+void Settings::setVersionMinor(const uint versionMinor)
+{
+ // Don't cache this value; ignore the group
+ create_qsettings;
+ // Set the value directly.
+ s.setValue("Config/VersionMinor", versionMinor);
+}
+
+QSettings::Format Settings::format() const
+{
+#ifdef Q_OS_WIN
+ return QSettings::IniFormat;
+#else
+ return QSettings::NativeFormat;
+#endif
+}
+
+bool Settings::sync()
+{
+ create_qsettings;
+ s.sync();
+ switch (s.status()) {
+ case QSettings::NoError:
+ return true;
+ default:
+ return false;
+ }
+}
+
+bool Settings::isWritable() const
+{
+ create_qsettings;
+ return s.isWritable();
+}