const Lang = imports.lang;
const GLib = imports.gi.GLib;
const Gio = imports.gi.Gio;

const CommandLineUtil = new Lang.Class({
    Name: 'CommandLineUtil',

    _init: function(){
        this._argv = null;
        this._updated = false;
    },

    execute: function(callback) {
        try{
            this._callback = callback;
            let [exit, pid, stdinFd, stdoutFd, stderrFd] =
                GLib.spawn_async_with_pipes(null, /* cwd */
                                            this._argv, /* args */
                                            null, /* env */
                                            GLib.SpawnFlags.DO_NOT_REAP_CHILD,
                                            null /* child_setup */);
            let stdout = new Gio.UnixInputStream({fd: stdoutFd, close_fd: true});
            let outReader = new Gio.DataInputStream({base_stream: stdout});

            let stderr = new Gio.UnixInputStream({fd: stderrFd, close_fd: true});
            let errReader = new Gio.DataInputStream({base_stream: stderr});

            GLib.close(stdinFd);

            let childWatch = GLib.child_watch_add(GLib.PRIORITY_DEFAULT, pid, Lang.bind(this, function(pid, status, requestObj) {
                let output = [];
                let [line, size] = [null, 0];

                while (([line, size] = outReader.read_line(null)) != null && line != null) {
                    if(line)
                        output.push(line.toString());
                }
                stdout.close(null);

                while (([line, size] = errReader.read_line(null)) != null && line != null) {
                    if(line)
                        output.push(line.toString());
                }
                stderr.close(null);

                GLib.source_remove(childWatch);
                this._output = output;
                this._updated = true;
                callback();
            }));
        } catch(e){
            global.log(e.toString());
        }
    },

    get available(){
        return this._argv != null;
    },

    get updated (){
       return this._updated;
    },
 
    set updated (updated){
        this._updated = updated;
    },

    destroy: function(){
        this._argv = null;
    }

});