package org.onlab.onos.proxyarp;

import static org.slf4j.LoggerFactory.getLogger;

import org.apache.felix.scr.annotations.Activate;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Deactivate;
import org.apache.felix.scr.annotations.Reference;
import org.apache.felix.scr.annotations.ReferenceCardinality;
import org.onlab.onos.ApplicationId;
import org.onlab.onos.net.packet.PacketContext;
import org.onlab.onos.net.packet.PacketProcessor;
import org.onlab.onos.net.packet.PacketService;
import org.onlab.onos.net.proxyarp.ProxyArpService;
import org.slf4j.Logger;

/**
 * Sample reactive proxy arp application.
 */
@Component(immediate = true)
public class ProxyArp {


    private final Logger log = getLogger(getClass());

    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
    protected PacketService packetService;

    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
    protected ProxyArpService proxyArpService;

    private ProxyArpProcessor processor = new ProxyArpProcessor();

    private ApplicationId appId;

    @Activate
    public void activate() {
        appId = ApplicationId.getAppId();
        packetService.addProcessor(processor, PacketProcessor.ADVISOR_MAX + 1);
        log.info("Started with Application ID {}", appId.id());
    }

    @Deactivate
    public void deactivate() {
        packetService.removeProcessor(processor);
        processor = null;
        log.info("Stopped");
    }


    /**
     * Packet processor responsible for forwarding packets along their paths.
     */
    private class ProxyArpProcessor implements PacketProcessor {

        @Override
        public void process(PacketContext context) {
            // Stop processing if the packet has been handled, since we
            // can't do any more to it.
            if (context.isHandled()) {
                return;
            }

            //handle the arp packet.
            proxyArpService.handleArp(context);
        }
    }
}