Refactor code to be more legible

src/extension.js

@@ -20,112 +20,165 @@ this program. If not, see <http s ://www.gnu.org/licenses/>.
 
 const Gio = imports.gi.Gio;
 
-let interface_settings, interface_settings_connect_id;
+const GSETTINGS_SCHEMA = 'org.gnome.desktop.interface';
-let nightlight_active;
+const GSETTINGS_PROPERTY = 'gtk-theme';
-let original_user_theme, user_theme_day, user_theme_night;
-let conn, proxy, proxy_connect_id;
 
 
-function _connect_dbus_proxy() {
+class Extension {
-	conn = Gio.bus_get_sync(Gio.BusType.SESSION, null);
+
-	if ( conn === null ) {
+	enable() {
-		throw new Error('Unable to connect to the session bus');
+		this.theme = new Themer();
+		this.variants = {};
+		this.variants = this._guess_theme_variants_from(this.theme.current);
+		this.theme.listen(this._on_theme_change.bind(this));
+
+		this.nightlight = new Nightlighter();
+		this.nightlight.listen(this._apply_theme_variant.bind(this));
+
+		this._apply_theme_variant();
 	}
-	proxy = Gio.DBusProxy.new_sync(
+
-		conn,
+	disable() {
-		Gio.DBusProxyFlags.GET_INVALIDATED_PROPERTIES,
+		if ( this.theme && this.variants ) {
-		null,
+			this.theme.current = this.variants.original;
-		'org.gnome.SettingsDaemon.Color',
+		}
-		'/org/gnome/SettingsDaemon/Color',
+		if ( this.theme ) {
-		'org.gnome.SettingsDaemon.Color',
+			this.theme.stop_listening();
-		null
+		}
-	);
+		this.theme = null;
-	if ( proxy === null ) {
+		this.variants = null;
-		throw new Error('Unable to create proxy to the session bus');
+
+		if ( this.nightlight ){
+			this.nightlight.stop_listening();
+		}
+		this.nightlight = null;
 	}
+
+	_apply_theme_variant() {
+		this.theme.current = this.nightlight.status ? this.variants.night : this.variants.day;
+	}
+
+	_on_theme_change() {
+		const new_theme = this.theme.current;
+		if ( new_theme === this.variants.day || new_theme === this.variants.night ) return;
+
+		this.variants = this._guess_theme_variants_from();
+		this._apply_theme_variant();
+	}
+
+	_guess_theme_variants_from(name) {
+		const variants = {};
+		variants.original = name;
+
+		if ( name.includes('HighContrast') ) {
+			variants.day = 'HighContrast';
+			variants.night = 'HighContrastInverse';
+		}
+		else if ( name.match(/Materia.*-compact/g) ) {
+			variants.day = name.replace(/-dark(?!er)/g, '');
+			variants.night = variants.day.replace(/(-light)?-compact/g, '-dark-compact');
+		}
+		else if ( name.includes('Arc') ) {
+			variants.day = name.replace(/-Dark(?!er)/g, '');
+			variants.night = variants.day.replace('-Darker', '') + '-Dark';
+		}
+		else {
+			variants.day = name.replace(/-dark(?!er)/g, '');
+			variants.night = variants.day.replace(/(-light)?(-darker)?/g, '') + '-dark';
+		}
+
+		return variants;
+	}
+
 }
 
-function _get_theme() {
+
-	return interface_settings.get_string('gtk-theme');
+class Themer {
+
+	constructor() {
+		try {
+			this.gsettings = new Gio.Settings({ schema: GSETTINGS_SCHEMA });
+		}
+		catch(e)
+		{
+			logError('"User Themes" GNOME Shell extension must be installed')
+		}
+	}
+
+	get current() {
+		return this.gsettings.get_string(GSETTINGS_PROPERTY);
+	}
+
+	set current(theme) {
+		if ( theme === this.current ) return;
+		this.gsettings.set_string(GSETTINGS_PROPERTY, theme);
+	}
+
+	listen(callback) {
+		this.connect = this.gsettings.connect(`changed::${GSETTINGS_PROPERTY}`, callback);
+	}
+
+	stop_listening() {
+		if ( this.gsettings && this.connect ){
+			this.gsettings.disconnect(this.connect);
+		}
+	}
+
 }
 
-function _set_theme(theme) {
+
-	if ( theme === _get_theme() ) return;
+class Nightlighter {
-	interface_settings.set_string('gtk-theme', theme);
+
+	constructor() {
+		try {
+			this._connect_to_dbus();
+		}
+		catch(e) {
+			logError(e);
+		}
+	}
+
+	get status() {
+		try {
+			return this.proxy.get_cached_property('NightLightActive').get_boolean();
+		}
+		catch(e) {
+			return false;
+		}
+	}
+
+	listen(callback) {
+		this.connect = this.proxy.connect('g-properties-changed', callback);
+	}
+
+	stop_listening() {
+		if ( this.proxy && this.connect ) {
+			this.proxy.disconnect(this.connect);
+		}
+	}
+
+	_connect_to_dbus() {
+		const connection = Gio.bus_get_sync(Gio.BusType.SESSION, null);
+		if ( connection === null ) {
+			throw new Error('Unable to connect to the session bus');
+		}
+		this.proxy = Gio.DBusProxy.new_sync(
+			connection,
+			Gio.DBusProxyFlags.GET_INVALIDATED_PROPERTIES,
+			null,
+			'org.gnome.SettingsDaemon.Color',
+			'/org/gnome/SettingsDaemon/Color',
+			'org.gnome.SettingsDaemon.Color',
+			null
+		);
+		if ( this.proxy === null ) {
+			throw new Error('Unable to create proxy to the session bus');
+		}
+	}
+
 }
 
-function _build_theme_variants() {
-	if ( original_user_theme.includes('HighContrast') ) {
-		user_theme_day = 'HighContrast';
-		user_theme_night = 'HighContrastInverse';
-	}
-	else if ( original_user_theme.match(/Materia.*-compact/g) ) {
-		user_theme_day = original_user_theme.replace(/-dark(?!er)/g, '');
-		user_theme_night = user_theme_day.replace(/(-light)?-compact/g, '-dark-compact');
-	}
-	else if ( original_user_theme.includes('Arc') ) {
-		user_theme_day = original_user_theme.replace(/-Dark(?!er)/g, '');
-		user_theme_night = user_theme_day.replace('-Darker', '') + '-Dark';
-	}
-	else {
-		user_theme_day = original_user_theme.replace(/-dark(?!er)/g, '');
-		user_theme_night = user_theme_day.replace(/(-light)?(-darker)?/g, '') + '-dark';
-	}
-}
 
-function _apply_theme_variant() {
+function init() {
-	try {
+	return new Extension();
-		nightlight_active = proxy.get_cached_property('NightLightActive').get_boolean();
-	}
-	catch(e) {
-		nightlight_active = false;
-	}
-	_set_theme(nightlight_active ? user_theme_night : user_theme_day);
-}
-
-function init() {}
-
-function enable() {
-	// Store the current user theme and build day and night variants
-	interface_settings = new Gio.Settings({ schema: 'org.gnome.desktop.interface' });
-	original_user_theme = _get_theme();
-	_build_theme_variants();
-
-	// Connect to session bus, listen to Color changes and change theme variant
-	try {
-		_connect_dbus_proxy();
-	}
-	catch(e) {
-		logError(e);
-	}
-	proxy_connect_id = proxy.connect('g-properties-changed', _apply_theme_variant);
-	_apply_theme_variant();
-
-	// Listen to theme change, don't change if this is the same theme
-	interface_settings_connect_id = interface_settings.connect('changed::gtk-theme', () => {
-		const new_theme = _get_theme();
-		if ( new_theme === user_theme_day || new_theme === user_theme_night ) return;
-		original_user_theme = new_theme;
-		_build_theme_variants();
-		_apply_theme_variant();
-	});
-}
-
-function disable() {
-	if ( proxy && proxy_connect_id ) {
-		proxy.disconnect(proxy_connect_id);
-	}
-	interface_settings.disconnect(interface_settings_connect_id);
-
-	_set_theme(original_user_theme);
-
-	interface_settings = null;
-	interface_settings_connect_id = null;
-	nightlight_active = null;
-	original_user_theme = null;
-	user_theme_day = null;
-	user_theme_night = null;
-	conn = null;
-	proxy = null;
-	proxy_connect_id = null;
 }

src/metadata.json

@@ -3,6 +3,6 @@
 	"description": "Change theme to dark variant when Night Light activates",
 	"uuid": "nightthemeswitcher@romainvigier.fr",
 	"url": "https://gitlab.com/rmnvgr/nightthemeswitcher-gnome-shell-extension/",
-	"version": 5,
+	"version": 6,
 	"shell-version": ["3.28", "3.30","3.32", "3.34"]
 }