GnomeShellGenericMonitor/extension.js

/* extension.js
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 */

/* Based on https://stackoverflow.com/questions/33001192/how-to-send-a-string-to-a-gnome-shell-extension */

/*
  Some useful documentation :

  https://github.com/bananenfisch/RecentItems/blob/master/extension.js
  https://github.com/julio641742/gnome-shell-extension-reference/blob/master/tutorials/POPUPMENU-EXTENSION.md
  https://gjs-docs.gnome.org/st10~1.0_api/st.widget
  https://gitlab.gnome.org/GNOME/gnome-shell/-/blob/master/js/ui/panelMenu.js
  https://gitlab.gnome.org/GNOME/gnome-shell/-/blob/master/js/ui/popupMenu.js
  https://gitlab.gnome.org/GNOME/gnome-shell/-/blob/master/js/ui/panel.js
*/

const St = imports.gi.St;
const Gio = imports.gi.Gio;
const Lang = imports.lang;
const GLib = imports.gi.GLib
const Main = imports.ui.main;
const Mainloop = imports.mainloop;
const Clutter = imports.gi.Clutter;
const PanelMenu = imports.ui.panelMenu;
const PopupMenu = imports.ui.popupMenu;
const GObject = imports.gi.GObject;
const Pixbuf = imports.gi.GdkPixbuf;
const Cogl = imports.gi.Cogl;

function hash_get(hash, key, default_value) {
    if (hash.hasOwnProperty(key))
	return hash[key];

    return default_value;
}

function log(message) {
    global.log('[GenericMontior]', message);
}

var MyPopupMenuItem = GObject.registerClass({
  GTypeName: "MyPopupMenuItem"
},
class MyPopupMenuItem extends PopupMenu.PopupBaseMenuItem {
    _init(widgets, params) {
	super._init(params);

	this.box = new St.BoxLayout({ style_class: 'popup-combobox-item' });
	this.box.set_vertical(true);

	for (let widgetIndex in widgets)
	    this.box.add(widgets[widgetIndex]);
	
	this.add_child(this.box);
    }
});


var MonitorWidget = GObject.registerClass({
  GTypeName: "MonitorWidget"
},
class MonitorWidget extends PanelMenu.Button {


    _init(item, group, dbus, position) {	
	super._init(0.0);
	
        this.name = item['name'];
        this.group = group;
	this.fullname = this.name + '@' + this.group;
	this.dbus = dbus;
	this.signals = {}

        if (item.hasOwnProperty('icon'))
	{
	    if (typeof(item['icon']) === "string")
		this.icon = this._createIconOld(item);
	    else
		this.icon = this._createIcon(item['icon']);
	    if (this.icon !== null) {
		this._connectWidgetSignals(this.icon);
		this.add_child(this.icon);
	    }
	}
	else
	    this.icon = null;
	
        if (item.hasOwnProperty('text'))
	{
	    if (typeof(item['text']) === "string")
		this.widget = this._createTextOld(item);
	    else
		this.widget = this._createText(item['text']);

	    if (this.widget !== null) {
		this._connectWidgetSignals(this.widget);
		this.add_child(this.widget);
	    }
	}
	else
	    this.widget = null;
	
        if (item.hasOwnProperty('popup'))
            this._createPopup(item['popup']);

	this.onClick         = hash_get(item, 'on-click', '');
	this.onDblClick      = hash_get(item, 'on-dblclick', '');
	this.onRightClick    = hash_get(item, 'on-rightclick', '');
	this.onRightDblClick = hash_get(item, 'on-rightdblclick', '');
	this.onEnter         = hash_get(item, 'on-enter',  '');
	this.onLeave         = hash_get(item, 'on-leave',  '');
	this.onScroll        = hash_get(item, 'on-scroll', '');

        let box = hash_get(item, 'box', 'center');

	if (box === 'right' && position == -1)
	    position = 0;
	
	this.connect('style-changed', this._onStyleChanged.bind(this));

	// Disable click event at PanelMenu.button level
	this.setSensitive(false);
	
	this.nbClicks = 0;
	this.button = -1;

	Main.panel.addToStatusArea(this.fullname, this, position, box);
    }

    _onStyleChanged(actor) {
	// Force these values to avoid big spaces between each widgets
        this._minHPadding = 1;
        this._natHPadding = 1;
    }

    _connectWidgetSignals(widget) {
	this.signals[widget] = [];
	let id;
	id = widget.connect('enter-event', this._onEnter.bind(this));
	this.signals[widget].push(id);
	id = widget.connect('leave-event', this._onLeave.bind(this));
	this.signals[widget].push(id);
	id = widget.connect('scroll-event', this._onScroll.bind(this));
	this.signals[widget].push(id);
	widget.set_reactive(true);
	id = widget.connect('button-release-event', Lang.bind(this, this._clicked));
	this.signals[widget].push(id);
    }

    _disconnectWidgetSignals(widget) {
	for(let idx in this.signals[widget])
	    widget.disconnect(this.signals[widget][idx]);
	this.signals[widget] = null;
    }
    
    _createPopup(item) {
        if (!item.hasOwnProperty('items')) {
	    return null;
	}

	let widgets = [];
	for (let itemIndex in item['items']) {
	    let widget = null;
	    let widgetDict = item['items'][itemIndex];

	    if (widgetDict.hasOwnProperty('text'))
		widget = this._createText(widgetDict['text']);
	    else if (widgetDict.hasOwnProperty('picture'))
		widget = this._createPicture(widgetDict['picture']);

	    if (widget !== null)
		widgets.push(widget);
	}

	if (widgets.length > 0) {
	    this.menuItem = new MyPopupMenuItem(widgets, {});	
            this.menu.addMenuItem(this.menuItem);
	    this.menu.setSensitive(false);
	    return this.menuItem;
	}

	return null;
    }
    
    _createTextOld(item) {
	var item_values = {};
	item_values = {'text':item['text']};
        if (item.hasOwnProperty('style'))
	    item_values['style'] = item['style'];
	return this._createText(item_values);
    }
    
    _createText(item) {
        if (!item.hasOwnProperty('text')) {
	    log("Text must have a \'text\' value");
	    return null;
	}

	let style = hash_get(item, 'style', '');

	this.textProperties = item;

	if (item['text'] === '') {
            return null;
        } else {
            let widget = new St.Button({ label: item['text'] });
            widget.set_style(style);

	    return widget;
	}
    }

    _createIconOld(item) {
	var item_values = {};
	item_values = {'path':item['icon']};
        if (item.hasOwnProperty('iconStyle'))
	    item_values['style'] = item['iconStyle'];
	return this._createIcon(item_values);
    }

    _createIcon(item) {
        if (!item.hasOwnProperty('path')) {
	    log("Icon must have a \'path\' value");
	    return null;
	}

	let style = hash_get(item, 'style', '');

	this.iconProperties = item;

	if (item['path'] === '') {
            return null;
        } else {
            let gicon = Gio.icon_new_for_string(item['path']);
            gicon = new St.Icon({ gicon });
            gicon.set_style(style);

	    return gicon;
        }
    }

    _createPicture(item) {
        if (!item.hasOwnProperty('path')) {
	    log("Picture must have a \'path\' value");
	    return null;
	}

	let width = hash_get(item, 'width', -1);
	let height = hash_get(item, 'height', -1);

	if (typeof(width) === "string")
	    width = parseInt(width, 10);

	if (typeof(heigth) === "string")
	    heigth = parseInt(heigth, 10);

	let img = new Clutter.Image();
	let initial_pixbuf = Pixbuf.Pixbuf.new_from_file(item['path']);
	img.set_data(initial_pixbuf.get_pixels(),
			   initial_pixbuf.get_has_alpha() ? Cogl.PixelFormat.RGBA_8888
                           : Cogl.PixelFormat.RGB_888,
			   initial_pixbuf.get_width(),
			   initial_pixbuf.get_height(),
			   initial_pixbuf.get_rowstride());
	let picture = new Clutter.Actor();
	picture.set_content(img);
	picture.set_size((width != -1)?width:initial_pixbuf.get_width(),
		      (height != -1)?height:initial_pixbuf.get_height());

	// Pack it in a box to avoid picture resize
	let box = new St.BoxLayout({});
	box.add_child(picture);

	return box;
    }

    _manageEventAction(action) {
	if (action === 'open-popup')
	    this.menu.open(true);
	else if (action === 'close-popup')
	    this.menu.close();
	else if (action === 'toggle-popup')
	    this.menu.toggle();
	else if (action == 'delete')
	    this.dbus.deleteItem(this, this.group);

	return Clutter.EVENT_PROPAGATE;
    }
    
    _manageLeaveEvent() {
	this._manageEventAction(this.onLeave);
    }
    
    _doClickCallback() {
        let right = '';
        let nbClicks = '';
        if (this.button == 3)
	    right = 'Right';
        if (this.nbClicks > 1)
	    nbClicks = 'Dbl';
        let signalName = 'on' + right + nbClicks + 'Click';

	let action = 'signal';
	switch(signalName) {
	case 'onClick':         action = this.onClick; break;
	case 'onDblClick':      action = this.onDblClick; break;
	case 'onRightClick':    action = this.onRightClick; break;
	case 'onRightDblClick': action = this.onRightDblClick; break;
	}

	if (action === 'signal')
            this.dbus.emit_signal(signalName, this.fullname);
	else
	    this._manageEventAction(action);
	this.nbClicks = 0;
	this.button = -1;

	return false;
    }

    _clicked(actor, event) {
	if (event.get_button() == this.button) {
	    this.nbClicks++;
	} else {
	    this.button = event.get_button();
	    this.nbClicks = 1;

	    Mainloop.timeout_add(this.dbus.ClutterSettings['double-click-time'],
				 Lang.bind(this, this._doClickCallback));
	}

	return Clutter.EVENT_PROPAGATE;
    }
    
    _onEnter(actor, event) {
	if (this.onEnter === 'signal')
	    this.dbus.emit_signal('onEnter', this.fullname);
	else
	    return this._manageEventAction(this.onEnter);

	return Clutter.EVENT_PROPAGATE;
    }

    _onLeave(actor, event) {
	if (this.onLeave === 'signal')
	    this.dbus.emit_signal('onLeave', this.fullname);
	else
	    return this._manageEventAction(this.onEnter);

	return Clutter.EVENT_PROPAGATE;
    }

    _onScroll(actor, event) {
	if (this.onScroll === 'signal') {
	    let direction = event.get_scroll_direction ();
	    if (direction ==  Clutter.ScrollDirection.UP)
		this.dbus.emit_signal('onScrollUp', this.fullname);
	    else if (direction ==  Clutter.ScrollDirection.DOWN)
		this.dbus.emit_signal('onScrollDown', this.fullname);
	} else
	    return this._manageEventAction(this.onEnter);

	return Clutter.EVENT_PROPAGATE;
    }

    update(item) {
        let prevWidget = this.widget;
        let prevIcon = this.icon;

        if (item.hasOwnProperty('text'))
	{
	    let text = '';
	    let style = '';
	    if (typeof(item['text']) === "string") {
		text = hash_get(item, 'text', '');
		style = hash_get(item, 'style', '');
	    } else {
		let textValues = item['text'];
		text = hash_get(textValues, 'text', '');
		style = hash_get(textValues, 'style', '');
	    }
	    
            if (text !== '') {
		if (!this.widget) {
		    if (typeof(item['text']) === "string")
			this.widget = this._createTextOld(item);
		    else
			this.widget = this._createText(item['text']);
                    this.insert_child_above(this.widget, this.icon);
		} else {
                    this.widget.label = text;
		}
	    }

            if (style !== '' && this.widget) {
		this.widget.set_style(style);
            }
        }

        if (item.hasOwnProperty('icon'))
	{
	    let icon = '';
	    let style = '';
	    if (typeof(item['icon']) === "string") {
		icon = hash_get(item, 'icon', '');
		style = hash_get(item, 'iconStyle', '');
	    } else {
		let iconValues = item['icon'];
		icon = hash_get(iconValues, 'path', '');
		style = hash_get(textValues, 'style', '');
	    }
	    
            if (icon !== '') {
		if (typeof(item['icon']) === "string")
		    this.icon = this._createIconOld(item);
		else
		    this.icon = this._createIcon(item['icon']);
	    }
	    
            if (prevIcon) {
		this._disconnectWidgetSignals(prevIcon);
                this.insert_child_above(this.icon, prevIcon);
		this.remove_child(prevIcon);
		//delete prevIcon;
            } else
                this.insert_child_before(this.icon, prevWidget);

            if (style !== '' && this.icon) {
		this.icon.set_style(style);
            }
        }

        if (item.hasOwnProperty('popup'))
	{
	    let menuOpen = this.menu.isOpen;
	    if (this.menuItem) {
		if (menuOpen)
		    this.menu.close();
		this.menu.removeAll();
		//delete this.menuItem;
	    }

	    let popup = this._createPopup(item['popup']);
	    if (popup !== null && menuOpen)
		this.menu.open(true);
	}

	this.onClick         = hash_get(item, 'on-click', this.onClick);
	this.onDblClick      = hash_get(item, 'on-dblclick', this.onDblClick);
	this.onRightClick    = hash_get(item, 'on-rightclick', this.onRightClick);
	this.onRightDblClick = hash_get(item, 'on-rightdblclick', this.onRightDblClick);
	this.onEnter         = hash_get(item, 'on-enter',  this.onEnter);
	this.onLeave         = hash_get(item, 'on-leave',  this.onLeave);
	this.onScroll        = hash_get(item, 'on-scroll', this.onScroll);
    }

    openPopup() {
	this.menu.open(true);
    }
    
    closePopup() {
	this.menu.close();
    }

    togglePopup() {
	this.menu.toggle();
    }

    destroy() {
	this.menu.close();
	super.destroy();
    }
});

// From https://github.com/ubuntu/gnome-shell-extension-appindicator/blob/master/interfaces.js
// loads a xml file into an in-memory string
function loadInterfaceXml(filename) {
    let extension = imports.misc.extensionUtils.getCurrentExtension();

    let interfacesDir = extension.dir.get_child('.');

    let file = interfacesDir.get_child(filename);

    let [result, contents] = imports.gi.GLib.file_get_contents(file.get_path());

    if (result) {
        // HACK: The "" + trick is important as hell because file_get_contents returns
        // an object (WTF?) but Gio.makeProxyWrapper requires `typeof() == "string"`
        // Otherwise, it will try to check `instanceof XML` and fail miserably because there
        // is no `XML` on very recent SpiderMonkey releases (or, if SpiderMonkey is old enough,
        // will spit out a TypeError soon).
        if (contents instanceof Uint8Array)
            contents = imports.byteArray.toString(contents);
        let res = `<node>${contents}</node>`;
        return res;
    } else {
        throw new Error(`Generic monitor: Could not load file: ${filename}`);
    }
}

class GenericMonitorDBUS {
    constructor() {
        this.monitor_groups = {};
        this.actor_clicked = {};
        this.ClutterSettings = Clutter.Settings.get_default();
        this._dbusImpl = Gio.DBusExportedObject.wrapJSObject(loadInterfaceXml('dbus.xml'), this);
        this._dbusImpl.export(Gio.DBus.session, '/com/soutade/GenericMonitor');
        this._dbusImpl.emit_signal('onActivate', null);
    }

    emit_signal(name, value) {
        this._dbusImpl.emit_signal(name, GLib.Variant.new('(s)',[value]));
    }

    _checkParameters(parameters) {
        if (!parameters.hasOwnProperty('group')) {
	    log('No group defined');
	    return false;
	}

	if (!parameters.hasOwnProperty('items')) {
	    log('No items defined');
	    return false;
	}

        for (let itemIndex in parameters['items']) {
            let item = parameters['items'][itemIndex];
            if (!item.hasOwnProperty('name')) {
		log('No name defined for item');
		return false;
	    }
        }

	return true;
    }

    _getItemFromGroup(group, name) {
        for (let groupItemIndex in group) {
            let groupItem = group[groupItemIndex];
            if (groupItem.name === name)
                return groupItem;
        }

        return null;
    }

    _getItemFromFullName(fullname) {
	let splitName = fullname.split('@');
        if (splitName.length !== 2) {
	    log(`Invalid name ${item}`);
	    return null;
	}
	if (!this.monitor_groups.hasOwnProperty(splitName[1]))
	    return null;
	return this._getItemFromGroup(this.monitor_groups[splitName[1]], splitName[0]);
    }
    
    _removeFromArray(array, value) {
        for(let i=0; i<array.length; i++) {
            if (array[i] === value) {
                array.splice(i, 1);
                if (array === null)
                    array = [];
                break;
            }
        }
        return array;
    }
    
    notify(str) {
        let parameters = JSON.parse(str);
        if (!this._checkParameters(parameters))
	    return;

        let groupName = parameters['group'];
        let group;
        if (!this.monitor_groups.hasOwnProperty(groupName)) {
            group = [];
            this.monitor_groups[groupName] = group;
        } else {
            group = this.monitor_groups[groupName];
        }

        for (let itemIndex in parameters['items']) {
            let item = parameters['items'][itemIndex];
            let monitorWidget = this._getItemFromGroup(group, item['name']);

            // New widget
            if (monitorWidget === null) {
		let position = group.length - 1;
		// Find real position
		if (position != -1) {
		    let lastWidget = group[position].container;
		    let childrens = lastWidget.get_parent().get_children();
		    for(;position < childrens.length; position++)
		    {
			if (childrens[position] == lastWidget) {
			    position++;
			    break;
			}
		    }
		    if (position >= childrens.length)
			position = -1;
		}
                monitorWidget = new MonitorWidget(item, groupName, this, position);
                group.push(monitorWidget);
            } else {
                monitorWidget.update(item);
            }
        }
    }

    deleteItem(item, groupName) {
        let group = this.monitor_groups[groupName];
        group = this._removeFromArray(group, item);
	item.destroy();
        if (group.length === 0)
            delete this.monitor_groups[groupName];
        else
            this.monitor_groups = group;
    }
    
    deleteItems(str) {
        let parameters = JSON.parse(str);

        if (!parameters.hasOwnProperty('items')) {
	    log('No items defined');
	    return false;
	}

        for (let itemIndex in parameters['items']) {
            let itemName = parameters['items'][itemIndex];
            let splitName = itemName.split('@');
            if (splitName.length !== 2) {
		log(`Invalid name ${itemName}`);
		return false;
	    }
            itemName = splitName[0];
            let groupName = splitName[1];
            if (!this.monitor_groups.hasOwnProperty(groupName))
                continue;
            let group = this.monitor_groups[groupName];
            let item = this._getItemFromGroup(group, itemName);
            if (item !== null) {
                this.deleteItem(item, groupName);
            }
        }
    }

    deleteGroups(str) {
        let parameters = JSON.parse(str);

        if (!parameters.hasOwnProperty('groups')) {
	    log('No groups defined');
	    return false;
	}

        let groupsToDelete = [];
        for (let groupIndex in parameters['groups']) {
            let groupName = parameters['groups'][groupIndex];
            if (!this.monitor_groups.hasOwnProperty(groupName))
                continue;
            let group = this.monitor_groups[groupName];
            for (let itemIndex in group)
		group[itemIndex].destroy();
            groupsToDelete.push(groupName);
        }
        for (let groupDeleteIndex in groupsToDelete) {
            let groupName = groupsToDelete[groupDeleteIndex];
            delete this.monitor_groups[groupName];
        }
    }

    _popupFunction(str) {
        let parameters = JSON.parse(str);

        if (!parameters.hasOwnProperty('item')) {
	    log('No item defined');
	    return false;
	}

	let monitorWidget = this._getItemFromFullName(parameters['item']);
	if (monitorWidget !== null)
	    return monitorWidget;
	else
	    log(`Item ${str} not found`);

	return null;
    }
    
    openPopup(str) {
	let monitorWidget = this._popupFunction(str)
	if (monitorWidget !== null)
	    monitorWidget.openPopup();
    }

    closePopup(str) {
	let monitorWidget = this._popupFunction(str)
	if (monitorWidget !== null)
	    monitorWidget.closePopup();
    }

    togglePopup(str) {
	let monitorWidget = this._popupFunction(str)
	if (monitorWidget !== null)
	    monitorWidget.togglePopup();
    }

    destructor() {
        this._dbusImpl.emit_signal('onDeactivate', null);
        for (let groupIndex in this.monitor_groups) {
            let group = this.monitor_groups[groupIndex];
            for (let itemIndex in group)
		group[itemIndex].destroy();
        }
        this.monitor_groups = {};
        this._dbusImpl.unexport();
    }
}

class Extension {
    enable() {
        this.textDBusService = new GenericMonitorDBUS();
    }

    disable() {
        this.textDBusService.destructor();
        delete this.textDBusService;
    }
}

let extension = new Extension();

function init() {
}

function enable() {
    extension.enable();
}

function disable() {
    extension.disable();
}