using Gee;

using Xmpp.Core;

namespace Xmpp.Xep.Ping {
    private const string NS_URI = "urn:xmpp:ping";

    public class Module : XmppStreamModule {
        public static ModuleIdentity<Module> IDENTITY = new ModuleIdentity<Module>(NS_URI, "0199_ping");

        public void send_ping(XmppStream stream, string jid, ResponseListener? listener) {
            Iq.Stanza iq = new Iq.Stanza.get(new StanzaNode.build("ping", NS_URI).add_self_xmlns());
            iq.to = jid;
            stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq, on_ping_response, listener);
        }

        public override void attach(XmppStream stream) {
            Iq.Module.require(stream);
            stream.get_module(Iq.Module.IDENTITY).register_for_namespace(NS_URI, new IqHandlerImpl());
        }

        public override void detach(XmppStream stream) { }

        public static void require(XmppStream stream) {
            if (stream.get_module(IDENTITY) == null) stream.add_module(new Module());
        }

        public override string get_ns() { return NS_URI; }
        public override string get_id() { return IDENTITY.id; }

        private class IqHandlerImpl : Iq.Handler, Object {
            public void on_iq_get(XmppStream stream, Iq.Stanza iq) {
                stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
            }
            public void on_iq_set(XmppStream stream, Iq.Stanza iq) { }
        }

        private static void on_ping_response(XmppStream stream, Iq.Stanza iq, Object? o) {
            ResponseListener? listener = o as ResponseListener;
            if (listener != null) listener.on_result(stream);
        }
    }

    public interface ResponseListener : Object {
        public abstract void on_result(XmppStream stream);
    }
}