/*
 * Copyright (c) 2016 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.lispflowmapping.neutron;

import static java.util.Objects.requireNonNull;

import java.util.Collection;
import org.opendaylight.mdsal.binding.api.ClusteredDataTreeChangeListener;
import org.opendaylight.mdsal.binding.api.DataBroker;
import org.opendaylight.mdsal.binding.api.DataObjectModification;
import org.opendaylight.mdsal.binding.api.DataTreeIdentifier;
import org.opendaylight.mdsal.binding.api.DataTreeModification;
import org.opendaylight.yang.gen.v1.urn.opendaylight.neutron.networks.rev150712.networks.attributes.networks.Network;
import org.opendaylight.yang.gen.v1.urn.opendaylight.neutron.ports.rev150712.ports.attributes.ports.Port;
import org.opendaylight.yang.gen.v1.urn.opendaylight.neutron.subnets.rev150712.subnets.attributes.subnets.Subnet;
import org.opendaylight.yangtools.concepts.ListenerRegistration;
import org.opendaylight.yangtools.yang.binding.DataObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Deprecated
public class DelegatingDataTreeListener<T extends DataObject> implements ClusteredDataTreeChangeListener<T>,
        AutoCloseable {
    private static final Logger LOG = LoggerFactory.getLogger(DelegatingDataTreeListener.class);
    private final DataProcessor<T> dataProcessor;
    private ListenerRegistration<ClusteredDataTreeChangeListener<T>> dataTreeChangeListenerRegistration;

    public DelegatingDataTreeListener(DataProcessor<T> dataProcessor, DataBroker dataBroker,
            DataTreeIdentifier<T> dataTreeIdentifier) {
        requireNonNull(dataBroker, "Can not instantiate Listener! Broker is null!");
        requireNonNull(dataTreeIdentifier, "DataTreeIndentifier can not be null!");
        this.dataProcessor = dataProcessor;
        dataTreeChangeListenerRegistration = dataBroker.registerDataTreeChangeListener(dataTreeIdentifier ,this);
    }

    public static <T extends DataObject> DelegatingDataTreeListener initiateListener(
            Class<T> dataObject, ILispNeutronService lispNeutronService, DataBroker dataBroker) {

        if (dataObject == Network.class) {
            return new NetworkListener(new NetworkDataProcessor(lispNeutronService), dataBroker);
        } else if (dataObject == Subnet.class) {
            return new SubnetListener(new SubnetDataProcessor(lispNeutronService), dataBroker);
        } else if (dataObject == Port.class) {
            return new PortListener(new PortDataProcessor(lispNeutronService), dataBroker);
        }
        LOG.debug(dataObject.getName() + " listener can not be instantiated.");
        return null;
    }

    @Override
    public void onDataTreeChanged(Collection<DataTreeModification<T>> changes) {
        for (DataTreeModification<T> change : changes) {
            DataObjectModification<T> mod = change.getRootNode();

            if (mod.getModificationType() == DataObjectModification.ModificationType.WRITE) {
                T object = mod.getDataAfter();
                dataProcessor.create(object);
                LOG.info(object.toString() + " created.");
            } else if (mod.getModificationType() == DataObjectModification.ModificationType.DELETE) {
                T object = mod.getDataBefore();
                dataProcessor.delete(object);
                LOG.info(object.toString() + " removed.");
            } else {
                T object = mod.getDataAfter();
                dataProcessor.update(object);
                LOG.info(object.toString() + " updated.");
            }
        }
    }

    @Override
    public void close() throws Exception {
        if (dataTreeChangeListenerRegistration != null) {
            dataTreeChangeListenerRegistration.close();
            dataTreeChangeListenerRegistration = null;

            LOG.info(this.toString() + " closed");
        }
    }
}