/*
 * Quasar: lightweight threads and actors for the JVM.
 * Copyright (c) 2013-2015, Parallel Universe Software Co. All rights reserved.
 * 
 * This program and the accompanying materials are dual-licensed under
 * either the terms of the Eclipse Public License v1.0 as published by
 * the Eclipse Foundation
 *  
 *   or (per the licensee's choosing)
 *  
 * under the terms of the GNU Lesser General Public License version 3.0
 * as published by the Free Software Foundation.
 */
package co.paralleluniverse.remote.galaxy;

import co.paralleluniverse.actors.Actor;
import co.paralleluniverse.actors.ActorImpl;
import co.paralleluniverse.actors.ActorRef;
import co.paralleluniverse.actors.spi.Migrator;
import co.paralleluniverse.fibers.SuspendExecution;
import co.paralleluniverse.galaxy.quasar.Grid;
import co.paralleluniverse.galaxy.quasar.Store;
import co.paralleluniverse.io.serialization.ByteArraySerializer;
import org.kohsuke.MetaInfServices;

/**
 *
 * @author pron
 */
@MetaInfServices
public class GlxMigrator implements Migrator {
    private final Grid grid;
    private final Store store;

    public GlxMigrator() {
        try {
            this.grid = Grid.getInstance();
            this.store = grid.store();
        } catch (InterruptedException ex) {
            throw new RuntimeException(ex);
        }
    }

    @Override
    public Object registerMigratingActor() throws SuspendExecution {
        try {
//            if (id == null)
            return store.put(new byte[0], null);
//            else {
//                store.getx((Long) id, null);
//                return id;
//            }
        } catch (co.paralleluniverse.galaxy.TimeoutException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void migrate(Object id, Actor actor, byte[] serialized) throws SuspendExecution {
        final long _id = (Long) id;
        try {
            store.setListener(_id, null); // stops the receiver
            store.set(_id, serialized, null);
            store.release(_id);
        } catch (co.paralleluniverse.galaxy.TimeoutException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public Actor hire(ActorRef actorRef, ActorImpl impl, ByteArraySerializer ser) throws SuspendExecution {
        final GlxGlobalChannelId gcid = ((GlxRemoteActor) impl).getId();
        if (!gcid.isGlobal())
            throw new IllegalArgumentException("Actor " + actorRef + " is not a migrating actor");

        final long id = gcid.getAddress();
        try {
            store.setListener(id, null);
            final byte[] buf = store.getx(id, null);
            assert buf != null : actorRef + " " + impl;
            
            final Object obj = ser.read(buf);
            final Actor actor;
            if (obj instanceof Actor)
                actor = (Actor) obj;
            else
                throw new IllegalArgumentException("Serialized object " + obj + " is not an actor.");
            
            GlobalRemoteChannelReceiver.getReceiver(actor.getMailbox(), id);
            return actor;
        } catch (co.paralleluniverse.galaxy.TimeoutException e) {
            throw new RuntimeException(e);
        }
    }

    private static GlxGlobalChannelId channelId(Object id) {
        return new GlxGlobalChannelId(true, (Long) id, -1);
    }
}