/**
 * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */
package org.opendaylight.openflowplugin.openflow.md.core.translator;

import java.math.BigInteger;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;

import org.opendaylight.openflowplugin.openflow.md.core.IMDMessageTranslator;
import org.opendaylight.openflowplugin.openflow.md.core.SwitchConnectionDistinguisher;
import org.opendaylight.openflowplugin.openflow.md.core.sal.convertor.match.MatchConvertorImpl;
import org.opendaylight.openflowplugin.openflow.md.core.session.SessionContext;
import org.opendaylight.openflowplugin.openflow.md.util.InventoryDataServiceUtil;
import org.opendaylight.openflowplugin.openflow.md.util.PacketInUtil;
import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.types.rev131026.FlowCookie;
import org.opendaylight.yang.gen.v1.urn.opendaylight.model.match.types.rev131026.Match;
import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.augments.rev131002.PortNumberMatchEntry;
import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.oxm.rev130731.oxm.fields.grouping.MatchEntries;
import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.protocol.rev130731.GetFeaturesOutput;
import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.protocol.rev130731.OfHeader;
import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.protocol.rev130731.PacketInMessage;
import org.opendaylight.yang.gen.v1.urn.opendaylight.packet.service.rev130709.PacketReceived;
import org.opendaylight.yang.gen.v1.urn.opendaylight.packet.service.rev130709.PacketReceivedBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.packet.service.rev130709.packet.received.MatchBuilder;
import org.opendaylight.yangtools.yang.binding.DataObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * translates packetIn from OF-API model to MD-SAL model, supports OF-1.3
 */
public class PacketInTranslator implements IMDMessageTranslator<OfHeader, List<DataObject>> {

    protected static final Logger LOG = LoggerFactory
            .getLogger(PacketInTranslator.class);
    @Override
    public List<DataObject> translate(SwitchConnectionDistinguisher cookie,
            SessionContext sc, OfHeader msg) {
        
        List<DataObject> salPacketIn = Collections.emptyList();
        
        if (sc != null && msg instanceof PacketInMessage) {
            PacketInMessage message = (PacketInMessage)msg;
            LOG.trace("PacketIn[v{}]: Cookie: {} Match.type: {}",
                    message.getVersion(), message.getCookie(), 
                    message.getMatch() != null ? message.getMatch().getType() : message.getMatch());

           // create a packet received event builder
           PacketReceivedBuilder pktInBuilder = new PacketReceivedBuilder();
           pktInBuilder.setPayload(message.getData());

           // get the DPID
           GetFeaturesOutput features = sc.getFeatures();
           // Make sure we actually have features, some naughty switches start sending packetIn before they send us the FeatureReply
           if ( features == null) {
               LOG.warn("Received packet_in, but there is no device datapathId received yet");
           } else {
               BigInteger dpid = features.getDatapathId();
    
               // get the Cookie if it exists
               if(message.getCookie() != null) {
                   pktInBuilder.setFlowCookie(new FlowCookie(message.getCookie()));
               }
               //TODO: use either canonical mapping or suitable hash -> 32b
               //pktInBuilder.setConnectionCookie(cookie);
    
               // extract the port number
               Long port = null;
               if (message.getMatch() != null && message.getMatch().getMatchEntries() != null) {
                   List<MatchEntries> entries = message.getMatch().getMatchEntries();
                   for (MatchEntries entry : entries) {
                       PortNumberMatchEntry tmp = entry.getAugmentation(PortNumberMatchEntry.class);
                       if (tmp != null) {
                           if (port == null) {
                               port = tmp.getPortNumber().getValue();
                           } else {
                               LOG.warn("Multiple input ports discovered when walking through match entries (at least {} and {})",
                                        port, tmp.getPortNumber().getValue());
                           }
                       }
                   }
               }
    
               if (port == null) {
                   // no incoming port, so drop the event
                   LOG.warn("Received packet_in, but couldn't find an input port");
               } else {
                   LOG.trace("Received packet_in from {} on port {}", dpid, port);
                   
                   Match match = MatchConvertorImpl.fromOFMatchToSALMatch(message.getMatch(),dpid);
                   MatchBuilder matchBuilder = new MatchBuilder(match);
                   pktInBuilder.setMatch(matchBuilder.build());
                   
                   pktInBuilder.setPacketInReason(PacketInUtil.getMdSalPacketInReason(message.getReason()));
                   pktInBuilder.setTableId(new org.opendaylight.yang.gen.v1.urn.opendaylight.table.types.rev131026.TableId(message.getTableId().getValue().shortValue()));
                   pktInBuilder.setIngress(InventoryDataServiceUtil.nodeConnectorRefFromDatapathIdPortno(dpid,port));
                   PacketReceived pktInEvent = pktInBuilder.build();
                   salPacketIn = new CopyOnWriteArrayList<DataObject>();
                   salPacketIn.add(pktInEvent);
               }
           } 
        } 
        return salPacketIn;
    }
}