/*
 * Copyright (c) 2015 - 2016 Ericsson India Global Services Pvt Ltd. 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.vpnservice.neutronvpn;


import org.opendaylight.controller.md.sal.binding.api.DataBroker;
import org.opendaylight.controller.md.sal.binding.api.DataChangeListener;
import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
import org.opendaylight.vpnservice.mdsalutil.AbstractDataChangeListener;
import org.opendaylight.yang.gen.v1.urn.opendaylight.neutron.ports.rev150712.port.attributes.FixedIps;
import org.opendaylight.yang.gen.v1.urn.opendaylight.neutron.ports.rev150712.ports.attributes.Ports;
import org.opendaylight.yang.gen.v1.urn.opendaylight.neutron.ports.rev150712.ports.attributes.ports.Port;
import org.opendaylight.yang.gen.v1.urn.opendaylight.neutron.rev150712.Neutron;
import org.opendaylight.yangtools.concepts.ListenerRegistration;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;


public class NeutronPortChangeListener extends AbstractDataChangeListener<Port> implements AutoCloseable {
    private static final Logger LOG = LoggerFactory.getLogger(NeutronPortChangeListener.class);

    private ListenerRegistration<DataChangeListener> listenerRegistration;
    private final DataBroker broker;
    private NeutronvpnManager nvpnManager;


    public NeutronPortChangeListener(final DataBroker db, NeutronvpnManager nVpnMgr) {
        super(Port.class);
        broker = db;
        nvpnManager = nVpnMgr;
        registerListener(db);
    }

    @Override
    public void close() throws Exception {
        if (listenerRegistration != null) {
            try {
                listenerRegistration.close();
            } catch (final Exception e) {
                LOG.error("Error when cleaning up DataChangeListener.", e);
            }
            listenerRegistration = null;
        }
        LOG.info("N_Port listener Closed");
    }


    private void registerListener(final DataBroker db) {
        try {
            listenerRegistration = db.registerDataChangeListener(LogicalDatastoreType.CONFIGURATION,
                    InstanceIdentifier.create(Neutron.class).child(Ports.class).child(Port.class),
                    NeutronPortChangeListener.this, DataChangeScope.SUBTREE);
        } catch (final Exception e) {
            LOG.error("Neutron Manager Port DataChange listener registration fail!", e);
            throw new IllegalStateException("Neutron Manager Port DataChange listener registration failed.", e);
        }
    }

    @Override
    protected void add(InstanceIdentifier<Port> identifier, Port input) {
        if (LOG.isTraceEnabled()) {
            LOG.trace("Adding Port : key: " + identifier + ", value=" + input);
        }
        nvpnManager.handleNeutronPortCreated(input);

    }

    @Override
    protected void remove(InstanceIdentifier<Port> identifier, Port input) {
        if (LOG.isTraceEnabled()) {
            LOG.trace("Removing Port : key: " + identifier + ", value=" + input);
        }
        nvpnManager.handleNeutronPortDeleted(input);

    }

    @Override
    protected void update(InstanceIdentifier<Port> identifier, Port original, Port update) {
        if (LOG.isTraceEnabled()) {
            LOG.trace("Updating Port : key: " + identifier + ", original value=" + original + ", update value=" +
                    update);
        }
        List<FixedIps> oldIPs = (original.getFixedIps() != null) ? original.getFixedIps() : new ArrayList<FixedIps>();
        List<FixedIps> newIPs = (update.getFixedIps() != null) ? update.getFixedIps() : new ArrayList<FixedIps>();

        if (!oldIPs.equals(newIPs)) {
            Iterator<FixedIps> iterator = newIPs.iterator();
            while (iterator.hasNext()) {
                FixedIps ip = iterator.next();
                if (oldIPs.remove(ip)) {
                    iterator.remove();
                }
            }
            nvpnManager.handleNeutronPortUpdated(original, update);
        }
    }
}