/*
 * Copyright (c) 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.interfacemgr.listeners;

import com.google.common.util.concurrent.ListenableFuture;
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;
import org.opendaylight.vpnservice.datastoreutils.AsyncDataChangeListenerBase;
import org.opendaylight.vpnservice.datastoreutils.DataStoreJobCoordinator;
import org.opendaylight.vpnservice.interfacemgr.renderer.ovs.statehelpers.OvsInterfaceTopologyStateUpdateHelper;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.ovsdb.rev150105.OvsdbTerminationPointAugmentation;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.NetworkTopology;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.Topology;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.Node;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.node.TerminationPoint;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.List;
import java.util.concurrent.Callable;

public class TerminationPointStateListener extends AsyncDataChangeListenerBase<OvsdbTerminationPointAugmentation, TerminationPointStateListener> {
    private static final Logger LOG = LoggerFactory.getLogger(TerminationPointStateListener.class);
    private DataBroker dataBroker;

    public TerminationPointStateListener(DataBroker dataBroker) {
        super(OvsdbTerminationPointAugmentation.class, TerminationPointStateListener.class);
        this.dataBroker = dataBroker;
    }

    @Override
    protected InstanceIdentifier<OvsdbTerminationPointAugmentation> getWildCardPath() {
        return InstanceIdentifier.builder(NetworkTopology.class).child(Topology.class)
                .child(Node.class).child(TerminationPoint.class).augmentation(OvsdbTerminationPointAugmentation.class).build();
    }

    @Override
    protected DataChangeListener getDataChangeListener() {
        return TerminationPointStateListener.this;
    }

    @Override
    protected AsyncDataBroker.DataChangeScope getDataChangeScope() {
        return AsyncDataBroker.DataChangeScope.SUBTREE;
    }

    @Override
    protected void remove(InstanceIdentifier<OvsdbTerminationPointAugmentation> identifier,
                          OvsdbTerminationPointAugmentation tpOld) {
    }

    @Override
    protected void update(InstanceIdentifier<OvsdbTerminationPointAugmentation> identifier,
                          OvsdbTerminationPointAugmentation tpOld,
                          OvsdbTerminationPointAugmentation tpNew) {
        LOG.debug("Received Update DataChange Notification for ovsdb termination point {}", tpNew.getName());
        if (tpNew.getInterfaceBfdStatus() != null &&
                !tpNew.getInterfaceBfdStatus().equals(tpOld.getInterfaceBfdStatus())) {
            LOG.trace("Bfd Status changed for ovsdb termination point identifier: {},  old: {}, new: {}.",
                    identifier, tpOld, tpNew);
            DataStoreJobCoordinator jobCoordinator = DataStoreJobCoordinator.getInstance();
            RendererStateUpdateWorker rendererStateAddWorker = new RendererStateUpdateWorker(identifier, tpNew, tpOld);
            jobCoordinator.enqueueJob(tpNew.getName(), rendererStateAddWorker);
        }
    }

    @Override
    protected void add(InstanceIdentifier<OvsdbTerminationPointAugmentation> identifier,
                       OvsdbTerminationPointAugmentation tpNew) {

    }

    private class RendererStateUpdateWorker implements Callable<List<ListenableFuture<Void>>> {
        InstanceIdentifier<OvsdbTerminationPointAugmentation> instanceIdentifier;
        OvsdbTerminationPointAugmentation terminationPointNew;
        OvsdbTerminationPointAugmentation terminationPointOld;


        public RendererStateUpdateWorker(InstanceIdentifier<OvsdbTerminationPointAugmentation> instanceIdentifier,
                                         OvsdbTerminationPointAugmentation tpNew, OvsdbTerminationPointAugmentation tpOld) {
            this.instanceIdentifier = instanceIdentifier;
            this.terminationPointNew = tpNew;
            this.terminationPointOld = tpOld;
        }

        @Override
        public List<ListenableFuture<Void>> call() throws Exception {
            // If another renderer(for eg : CSS) needs to be supported, check can be performed here
            // to call the respective helpers.
            return OvsInterfaceTopologyStateUpdateHelper.updateTunnelState(dataBroker,
                    terminationPointNew, terminationPointOld);
        }
    }
}