package edu.rice.comp322;

import edu.rice.hj.api.HjDataDrivenFuture;
import edu.rice.hj.runtime.actors.Actor;
import edu.rice.hj.runtime.util.Pair;

import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import java.util.Queue;

import static edu.rice.hj.Module0.launchHabaneroApp;
import static edu.rice.hj.Module0.newDDF;
import static edu.rice.hj.Module1.asyncAwait;

/**
 * <p>SyncReplyMain1 class.</p>
 *
 * @author <a href="http://shams.web.rice.edu/">Shams Imam</a> (shams@rice.edu)
 */
public class Lec29Slide15SyncReplyActor {

    private static final Object END = new Object();

    /**
     * <p>main.</p>
     *
     * @param args an array of {@link String} objects.
     */
    public static void main(final String[] args) {

        System.out.println("SyncReplyMain1.main starts...");

        launchHabaneroApp(() -> {

            final List<Integer> workItems = Arrays.asList(1, 2, 3, 4, 5);

            final ReceiverActor receiverActor = new ReceiverActor();
            receiverActor.start();

            final SenderActor senderActor = new SenderActor(receiverActor);
            senderActor.start();

            for (Object workItem : workItems) {
                System.out.println("Sending work item: " + workItem);
                senderActor.send(workItem);
            }
            senderActor.send(END);
        });

        System.out.println("SyncReplyMain1.main ends.");
    }

    private static class SenderActor extends Actor<Object> {

        private final ReceiverActor receiverActor;

        private SenderActor(final ReceiverActor receiverActor) {
            this.receiverActor = receiverActor;
        }

        @Override
        protected void process(final Object theMsg) {

            if (theMsg == END) {
                receiverActor.send(END);
                exit();
                return;
            }

            final HjDataDrivenFuture<Double> responseDDF = newDDF();
            pause();

            System.out.println("  SenderActor: sending " + theMsg);
            receiverActor.send(Pair.factory((Integer) theMsg, responseDDF));

            asyncAwait(responseDDF, () -> {
                final Object response = responseDDF.safeGet();
                System.out.println("  SenderActor: received " + response);
                resume();
            });
        }
    }

    private static class ReceiverActor extends Actor<Object> {

        private ReceiverActor() {
            super(true);
        }

        @Override
        protected void process(final Object theMsg) {

            if (theMsg == END) {
                exit();
                return;
            }

            @SuppressWarnings("unchecked")
            final Pair<Integer, HjDataDrivenFuture<Double>> msgPair = (Pair<Integer, HjDataDrivenFuture<Double>>) theMsg;
            final Integer senderMsg = msgPair.left;
            final HjDataDrivenFuture<Double> responseDdf = msgPair.right;
            System.out.println("    ReceiverActor: processing " + senderMsg);
            responseDdf.put(Double.valueOf(senderMsg * senderMsg));

        }
    }

}