/**
 * Copyright (c) 2014, 2017 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.applications.frm.impl;

import com.google.common.base.Preconditions;
import com.google.common.util.concurrent.CheckedFuture;
import com.google.common.util.concurrent.FutureCallback;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.MoreExecutors;
import java.util.concurrent.Future;
import org.opendaylight.controller.md.sal.binding.api.DataBroker;
import org.opendaylight.controller.md.sal.binding.api.DataTreeIdentifier;
import org.opendaylight.controller.md.sal.binding.api.WriteTransaction;
import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
import org.opendaylight.openflowplugin.applications.frm.ForwardingRulesManager;
import org.opendaylight.openflowplugin.common.wait.SimpleTaskRetryLooper;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Uri;
import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819.FlowCapableNode;
import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819.meters.Meter;
import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819.meters.StaleMeter;
import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819.meters.StaleMeterBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819.meters.StaleMeterKey;
import org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.NodeRef;
import org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.Nodes;
import org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.nodes.Node;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.service.rev130918.AddMeterInputBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.service.rev130918.AddMeterOutput;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.service.rev130918.RemoveMeterInputBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.service.rev130918.RemoveMeterOutput;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.service.rev130918.UpdateMeterInputBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.service.rev130918.meter.update.OriginalMeterBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.service.rev130918.meter.update.UpdatedMeterBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.types.rev130918.MeterId;
import org.opendaylight.yang.gen.v1.urn.opendaylight.meter.types.rev130918.MeterRef;
import org.opendaylight.yangtools.concepts.ListenerRegistration;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
import org.opendaylight.yangtools.yang.common.RpcResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * MeterForwarder It implements
 * {@link org.opendaylight.controller.md.sal.binding.api.DataTreeChangeListener}
 * for WildCardedPath to {@link Meter} and ForwardingRulesCommiter interface for
 * methods: add, update and remove {@link Meter} processing for
 * {@link org.opendaylight.controller.md.sal.binding.api.DataTreeModification}.
 *
 */
public class MeterForwarder extends AbstractListeningCommiter<Meter> {

    private static final Logger LOG = LoggerFactory.getLogger(MeterForwarder.class);
    private final DataBroker dataBroker;
    private ListenerRegistration<MeterForwarder> listenerRegistration;

    @SuppressWarnings("IllegalCatch")
    public MeterForwarder(final ForwardingRulesManager manager, final DataBroker db) {
        super(manager);
        dataBroker = Preconditions.checkNotNull(db, "DataBroker can not be null!");
        final DataTreeIdentifier<Meter> treeId = new DataTreeIdentifier<>(LogicalDatastoreType.CONFIGURATION,
                getWildCardPath());

        try {
            SimpleTaskRetryLooper looper = new SimpleTaskRetryLooper(ForwardingRulesManagerImpl.STARTUP_LOOP_TICK,
                    ForwardingRulesManagerImpl.STARTUP_LOOP_MAX_RETRIES);
            listenerRegistration = looper
                    .loopUntilNoException(() -> db.registerDataTreeChangeListener(treeId, MeterForwarder.this));
        } catch (final Exception e) {
            LOG.warn("FRM Meter DataTreeChange listener registration fail!");
            LOG.debug("FRM Meter DataTreeChange listener registration fail ..", e);
            throw new IllegalStateException("MeterForwarder startup fail! System needs restart.", e);
        }
    }

    @Override
    public void close() {
        if (listenerRegistration != null) {
            listenerRegistration.close();
            listenerRegistration = null;
        }
    }

    @Override
    protected InstanceIdentifier<Meter> getWildCardPath() {
        return InstanceIdentifier.create(Nodes.class).child(Node.class).augmentation(FlowCapableNode.class)
                .child(Meter.class);
    }

    @Override
    public void remove(final InstanceIdentifier<Meter> identifier, final Meter removeDataObj,
            final InstanceIdentifier<FlowCapableNode> nodeIdent) {

        final RemoveMeterInputBuilder builder = new RemoveMeterInputBuilder(removeDataObj);

        builder.setNode(new NodeRef(nodeIdent.firstIdentifierOf(Node.class)));
        builder.setMeterRef(new MeterRef(identifier));
        builder.setTransactionUri(new Uri(provider.getNewTransactionId()));
        this.provider.getSalMeterService().removeMeter(builder.build());
    }

    @Override
    public Future<RpcResult<RemoveMeterOutput>> removeWithResult(final InstanceIdentifier<Meter> identifier,
            final Meter removeDataObj, final InstanceIdentifier<FlowCapableNode> nodeIdent) {

        final RemoveMeterInputBuilder builder = new RemoveMeterInputBuilder(removeDataObj);

        builder.setNode(new NodeRef(nodeIdent.firstIdentifierOf(Node.class)));
        builder.setMeterRef(new MeterRef(identifier));
        builder.setTransactionUri(new Uri(provider.getNewTransactionId()));
        return this.provider.getSalMeterService().removeMeter(builder.build());
    }

    @Override
    public void update(final InstanceIdentifier<Meter> identifier, final Meter original, final Meter update,
            final InstanceIdentifier<FlowCapableNode> nodeIdent) {

        final UpdateMeterInputBuilder builder = new UpdateMeterInputBuilder();

        builder.setNode(new NodeRef(nodeIdent.firstIdentifierOf(Node.class)));
        builder.setMeterRef(new MeterRef(identifier));
        builder.setTransactionUri(new Uri(provider.getNewTransactionId()));
        builder.setUpdatedMeter(new UpdatedMeterBuilder(update).build());
        builder.setOriginalMeter(new OriginalMeterBuilder(original).build());

        this.provider.getSalMeterService().updateMeter(builder.build());
    }

    @Override
    public Future<RpcResult<AddMeterOutput>> add(final InstanceIdentifier<Meter> identifier, final Meter addDataObj,
            final InstanceIdentifier<FlowCapableNode> nodeIdent) {

        final AddMeterInputBuilder builder = new AddMeterInputBuilder(addDataObj);

        builder.setNode(new NodeRef(nodeIdent.firstIdentifierOf(Node.class)));
        builder.setMeterRef(new MeterRef(identifier));
        builder.setTransactionUri(new Uri(provider.getNewTransactionId()));
        return this.provider.getSalMeterService().addMeter(builder.build());
    }

    @Override
    public void createStaleMarkEntity(InstanceIdentifier<Meter> identifier, Meter del,
            InstanceIdentifier<FlowCapableNode> nodeIdent) {
        LOG.debug("Creating Stale-Mark entry for the switch {} for meter {} ", nodeIdent.toString(), del.toString());
        StaleMeter staleMeter = makeStaleMeter(del);
        persistStaleMeter(staleMeter, nodeIdent);
    }

    private StaleMeter makeStaleMeter(Meter del) {
        StaleMeterBuilder staleMeterBuilder = new StaleMeterBuilder(del);
        return staleMeterBuilder.setMeterId(del.getMeterId()).build();
    }

    private void persistStaleMeter(StaleMeter staleMeter, InstanceIdentifier<FlowCapableNode> nodeIdent) {
        WriteTransaction writeTransaction = dataBroker.newWriteOnlyTransaction();
        writeTransaction.put(LogicalDatastoreType.CONFIGURATION, getStaleMeterInstanceIdentifier(staleMeter, nodeIdent),
                staleMeter, false);

        CheckedFuture<Void, TransactionCommitFailedException> submitFuture = writeTransaction.submit();
        handleStaleMeterResultFuture(submitFuture);
    }

    private void handleStaleMeterResultFuture(CheckedFuture<Void, TransactionCommitFailedException> submitFuture) {
        Futures.addCallback(submitFuture, new FutureCallback<Void>() {
            @Override
            public void onSuccess(Void result) {
                LOG.debug("Stale Meter creation success");
            }

            @Override
            public void onFailure(Throwable throwable) {
                LOG.error("Stale Meter creation failed {}", throwable);
            }
        }, MoreExecutors.directExecutor());
    }

    private InstanceIdentifier<org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819
        .meters.StaleMeter> getStaleMeterInstanceIdentifier(
            StaleMeter staleMeter, InstanceIdentifier<FlowCapableNode> nodeIdent) {
        return nodeIdent.child(StaleMeter.class, new StaleMeterKey(new MeterId(staleMeter.getMeterId())));
    }
}