main-gjs.js

#!/usr/bin/env gjs
const IBus = imports.gi.IBus;
const GLib = imports.gi.GLib;
const GObject = imports.gi.GObject;
const Avroparser = imports.avrolib.OmicronLab.Avro.Phonetic;
const utfconv = imports.utf8;
const eevars = imports.evars;
//check if running from ibus
exec_by_ibus = (ARGV[0] == '--ibus')

// Let's initialize ibus
IBus.init();

//get the ibus bus
var bus = new IBus.Bus();

if( bus.is_connected() ) {

    var id = 0;

    function _create_engine_cb(factory, engine_name) {

        id += 1;
        var engine =  new IBus.Engine({
            engine_name: engine_name,
            object_path: '/org/freedesktop/IBus/Engine/' + id,
            connection: bus.get_connection()
        });

        engine.connect('process-key-event', function(engine,keyval,keycode,state) {

            //print keypress infos, helpful for debugging
            print(keyval + " " +  keycode + " " + state);

            // ignore release event
            if (!(state == 0 || state == 1 || state == 16 || state == 17)) {
                return false;
            }

            // capture the shift key
            if (keycode == 42) {
                return true;
            }

            // process letter key events
            if (keyval >= 33 && keyval <= 126) {
                engine.buffertext += IBus.keyval_to_unicode(keyval);
                let bntext = Avroparser.parse(engine.buffertext);
                bntext = utfconv.utf8Decode(bntext);
                let text = IBus.Text.new_from_string(bntext);
                engine.update_preedit_text(text,bntext.length,true);

                let entext = IBus.Text.new_from_string(engine.buffertext);
                engine.update_auxiliary_text(entext,true);
                return true;
            }
            else if (keyval == IBus.Return || keyval == IBus.space) {

                let bntext = Avroparser.parse(engine.buffertext);
                bntext = utfconv.utf8Decode(bntext);
                let text = IBus.Text.new_from_string(bntext);
                engine.commit_text(text);
                engine.buffertext = "";
                engine.hide_preedit_text();
                engine.hide_auxiliary_text();

                if (keyval == IBus.space) {
                    engine.commit_text( IBus.Text.new_from_string(" "));
                    return true;
                }
                /* i forgot what this commented block is here for !
                else {
                    // engine.forward_key_event(engine, 115, 31, state);
                    engine.commit_text( IBus.Text.new_from_string("\n") );
                    return true;
                }
                */
            }
            else if (keyval == IBus.BackSpace){
                if (engine.buffertext.length > 0) {
                    engine.buffertext = engine.buffertext.substr(0,engine.buffertext.length -1);
                    let bntext = Avroparser.parse(engine.buffertext);
                    bntext = utfconv.utf8Decode(bntext);
                    let text = IBus.Text.new_from_string(bntext);
                    engine.update_preedit_text(text,bntext.length,true);
                    let entext = IBus.Text.new_from_string(engine.buffertext);
                    engine.update_auxiliary_text(entext,true);
                    return true;
                }
            }
            else if (keyval == IBus.Left || keyval == IBus.Right || keyval == IBus.Up || keyval == IBus.Down || keyval == IBus.Control_L || keyval == IBus.Control_R || keyval == IBus.Insert   || keyval == IBus.Delete || keyval == IBus.Home || keyval == IBus.Page_Up || keyval == IBus.Page_Down || keyval == IBus.End || keyval == IBus.Alt_L || keyval == IBus.Alt_R ){
                let bntext = Avroparser.parse(engine.buffertext);
                bntext = utfconv.utf8Decode(bntext);
                let text = IBus.Text.new_from_string(bntext);
                engine.commit_text(text);
                engine.buffertext = "";
                engine.hide_preedit_text();
                engine.hide_auxiliary_text();
            }
            return false ;
        });

        engine.connect('focus-out', function (){
            if (engine.buffertext.length > 0) {
                let bntext = Avroparser.parse(engine.buffertext);
                bntext = utfconv.utf8Decode(bntext);
                let text = IBus.Text.new_from_string(bntext);
                engine.commit_text(text);
                engine.buffertext = "";
                engine.hide_preedit_text();
                engine.hide_auxiliary_text();
            }
        });

        engine.buffertext = "";
        return engine;
    }

    var factory = IBus.Factory.new( bus.get_connection() );
    //factory.add_engine("avro-phonetic",GObject.type_from_name('IBusEngine'));
    factory.connect('create-engine', _create_engine_cb);
    var component = new IBus.Component({
        name:"org.freedesktop.IBus.Avro",
        description:"Avro phonetic",
        version:"0.9",
        license:"MPL",
        author:"Sarim Khan <sarim2005@gmail.com>",
        homepage:"https://github.com/sarim/ibus-avro",
        exec: eevars.get_libexecdir() + "/main-gjs.js",
        textdomain:"avro-phonetic"
    });

    var avroenginedesc = new IBus.EngineDesc({
        name:"avro-phonetic",
        longname:"avro phonetic",
        description:"Avro Phonetic Engine",
        language:"bn",
        license:"MPL",
        author:"Sarim Khan <sarim2005@gmail.com>",
        icon: eevars.get_pkgdatadir() + "/avro-bangla.png",
        layout:"bn"
    });

    component.add_engine (avroenginedesc);
    if (exec_by_ibus) {
        bus.request_name ("org.freedesktop.IBus.Avro",0);
    } else {
        bus.register_component (component);
    }
    IBus.main();
}