1 files changed, 318 insertions, 0 deletions
diff --git a/js/misc/extensionUtils.js b/js/misc/extensionUtils.js
new file mode 100644
index 0000000..3e89a87
--- /dev/null
+++ b/js/misc/extensionUtils.js
@@ -0,0 +1,318 @@
+// -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
+/* exported ExtensionState, ExtensionType, getCurrentExtension,
+   getSettings, initTranslations, gettext, ngettext, pgettext,
+   openPrefs, isOutOfDate, installImporter, serializeExtension,
+   deserializeExtension, setCurrentExtension */
+
+// Common utils for the extension system and the extension
+// preferences tool
+
+const { Gio, GLib } = imports.gi;
+
+const Gettext = imports.gettext;
+
+const Config = imports.misc.config;
+
+let Main = null;
+
+try {
+    Main = imports.ui.main;
+} catch (error) {
+    // Only log the error if it is not due to the
+    // missing import.
+    if (error?.name !== 'ImportError')
+        console.error(error);
+}
+
+let _extension = null;
+
+var ExtensionType = {
+    SYSTEM: 1,
+    PER_USER: 2,
+};
+
+var ExtensionState = {
+    ENABLED: 1,
+    DISABLED: 2,
+    ERROR: 3,
+    OUT_OF_DATE: 4,
+    DOWNLOADING: 5,
+    INITIALIZED: 6,
+
+    // Used as an error state for operations on unknown extensions,
+    // should never be in a real extensionMeta object.
+    UNINSTALLED: 99,
+};
+
+const SERIALIZED_PROPERTIES = [
+    'type',
+    'state',
+    'path',
+    'error',
+    'hasPrefs',
+    'hasUpdate',
+    'canChange',
+];
+
+/**
+ * @param {object} extension the extension object to use in utilities like `initTranslations()`
+ */
+function setCurrentExtension(extension) {
+    if (Main)
+        throw new Error('setCurrentExtension() can only be called from outside the shell');
+
+    _extension = extension;
+}
+
+/**
+ * getCurrentExtension:
+ *
+ * @returns {?object} - The current extension, or null if not called from
+ * an extension.
+ */
+function getCurrentExtension() {
+    if (_extension)
+        return _extension;
+
+    let stack = new Error().stack.split('\n');
+    let extensionStackLine;
+
+    // Search for an occurrence of an extension stack frame
+    // Start at 1 because 0 is the stack frame of this function
+    for (let i = 1; i < stack.length; i++) {
+        if (stack[i].includes('/gnome-shell/extensions/')) {
+            extensionStackLine = stack[i];
+            break;
+        }
+    }
+    if (!extensionStackLine)
+        return null;
+
+    // The stack line is like:
+    //   init([object Object])@/home/user/data/gnome-shell/extensions/u@u.id/prefs.js:8
+    //
+    // In the case that we're importing from
+    // module scope, the first field is blank:
+    //   @/home/user/data/gnome-shell/extensions/u@u.id/prefs.js:8
+    let match = new RegExp('@(.+):\\d+').exec(extensionStackLine);
+    if (!match)
+        return null;
+
+    // local import, as the module is used from outside the gnome-shell process
+    // as well (not this function though)
+    let extensionManager = imports.ui.main.extensionManager;
+
+    let path = match[1];
+    let file = Gio.File.new_for_path(path);
+
+    // Walk up the directory tree, looking for an extension with
+    // the same UUID as a directory name.
+    while (file != null) {
+        let extension = extensionManager.lookup(file.get_basename());
+        if (extension !== undefined)
+            return extension;
+        file = file.get_parent();
+    }
+
+    return null;
+}
+
+/**
+ * initTranslations:
+ * @param {string=} domain - the gettext domain to use
+ *
+ * Initialize Gettext to load translations from extensionsdir/locale.
+ * If @domain is not provided, it will be taken from metadata['gettext-domain']
+ */
+function initTranslations(domain) {
+    let extension = getCurrentExtension();
+
+    if (!extension)
+        throw new Error('initTranslations() can only be called from extensions');
+
+    domain ||= extension.metadata['gettext-domain'];
+
+    // Expect USER extensions to have a locale/ subfolder, otherwise assume a
+    // SYSTEM extension that has been installed in the same prefix as the shell
+    let localeDir = extension.dir.get_child('locale');
+    if (localeDir.query_exists(null))
+        Gettext.bindtextdomain(domain, localeDir.get_path());
+    else
+        Gettext.bindtextdomain(domain, Config.LOCALEDIR);
+
+    Object.assign(extension, Gettext.domain(domain));
+}
+
+/**
+ * gettext:
+ * @param {string} str - the string to translate
+ *
+ * Translate @str using the extension's gettext domain
+ *
+ * @returns {string} - the translated string
+ *
+ */
+function gettext(str) {
+    return callExtensionGettextFunc('gettext', str);
+}
+
+/**
+ * ngettext:
+ * @param {string} str - the string to translate
+ * @param {string} strPlural - the plural form of the string
+ * @param {number} n - the quantity for which translation is needed
+ *
+ * Translate @str and choose plural form using the extension's
+ * gettext domain
+ *
+ * @returns {string} - the translated string
+ *
+ */
+function ngettext(str, strPlural, n) {
+    return callExtensionGettextFunc('ngettext', str, strPlural, n);
+}
+
+/**
+ * pgettext:
+ * @param {string} context - context to disambiguate @str
+ * @param {string} str - the string to translate
+ *
+ * Translate @str in the context of @context using the extension's
+ * gettext domain
+ *
+ * @returns {string} - the translated string
+ *
+ */
+function pgettext(context, str) {
+    return callExtensionGettextFunc('pgettext', context, str);
+}
+
+function callExtensionGettextFunc(func, ...args) {
+    const extension = getCurrentExtension();
+
+    if (!extension)
+        throw new Error(`${func}() can only be called from extensions`);
+
+    if (!extension[func])
+        throw new Error(`${func}() is used without calling initTranslations() first`);
+
+    return extension[func](...args);
+}
+
+/**
+ * getSettings:
+ * @param {string=} schema - the GSettings schema id
+ * @returns {Gio.Settings} - a new settings object for @schema
+ *
+ * Builds and returns a GSettings schema for @schema, using schema files
+ * in extensionsdir/schemas. If @schema is omitted, it is taken from
+ * metadata['settings-schema'].
+ */
+function getSettings(schema) {
+    let extension = getCurrentExtension();
+
+    if (!extension)
+        throw new Error('getSettings() can only be called from extensions');
+
+    schema ||= extension.metadata['settings-schema'];
+
+    const GioSSS = Gio.SettingsSchemaSource;
+
+    // Expect USER extensions to have a schemas/ subfolder, otherwise assume a
+    // SYSTEM extension that has been installed in the same prefix as the shell
+    let schemaDir = extension.dir.get_child('schemas');
+    let schemaSource;
+    if (schemaDir.query_exists(null)) {
+        schemaSource = GioSSS.new_from_directory(schemaDir.get_path(),
+                                                 GioSSS.get_default(),
+                                                 false);
+    } else {
+        schemaSource = GioSSS.get_default();
+    }
+
+    let schemaObj = schemaSource.lookup(schema, true);
+    if (!schemaObj)
+        throw new Error(`Schema ${schema} could not be found for extension ${extension.metadata.uuid}. Please check your installation`);
+
+    return new Gio.Settings({ settings_schema: schemaObj });
+}
+
+/**
+ * openPrefs:
+ *
+ * Open the preference dialog of the current extension
+ */
+function openPrefs() {
+    const extension = getCurrentExtension();
+
+    if (!extension)
+        throw new Error('openPrefs() can only be called from extensions');
+
+    try {
+        const extensionManager = imports.ui.main.extensionManager;
+        extensionManager.openExtensionPrefs(extension.uuid, '', {});
+    } catch (e) {
+        if (e.name === 'ImportError')
+            throw new Error('openPrefs() cannot be called from preferences');
+        logError(e, 'Failed to open extension preferences');
+    }
+}
+
+function isOutOfDate(extension) {
+    const [major] = Config.PACKAGE_VERSION.split('.');
+    return !extension.metadata['shell-version'].some(v => v.startsWith(major));
+}
+
+function serializeExtension(extension) {
+    let obj = { ...extension.metadata };
+
+    SERIALIZED_PROPERTIES.forEach(prop => {
+        obj[prop] = extension[prop];
+    });
+
+    let res = {};
+    for (let key in obj) {
+        let val = obj[key];
+        let type;
+        switch (typeof val) {
+        case 'string':
+            type = 's';
+            break;
+        case 'number':
+            type = 'd';
+            break;
+        case 'boolean':
+            type = 'b';
+            break;
+        default:
+            continue;
+        }
+        res[key] = GLib.Variant.new(type, val);
+    }
+
+    return res;
+}
+
+function deserializeExtension(variant) {
+    let res = { metadata: {} };
+    for (let prop in variant) {
+        let val = variant[prop].unpack();
+        if (SERIALIZED_PROPERTIES.includes(prop))
+            res[prop] = val;
+        else
+            res.metadata[prop] = val;
+    }
+    // add the 2 additional properties to create a valid extension object, as createExtensionObject()
+    res.uuid = res.metadata.uuid;
+    res.dir = Gio.File.new_for_path(res.path);
+    return res;
+}
+
+function installImporter(extension) {
+    let oldSearchPath = imports.searchPath.slice();  // make a copy
+    imports.searchPath = [extension.dir.get_parent().get_path()];
+    // importing a "subdir" creates a new importer object that doesn't affect
+    // the global one
+    extension.imports = imports[extension.uuid];
+    imports.searchPath = oldSearchPath;
+}