/*
 * Copyright (c) 2015 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.protocol.bgp.flowspec;

import com.google.common.collect.ImmutableCollection;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import java.util.Collection;
import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
import org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction;
import org.opendaylight.protocol.bgp.rib.spi.AbstractRIBSupport;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.flowspec.rev150807.FlowspecSubsequentAddressFamily;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.flowspec.rev150807.flowspec.ipv6.routes.flowspec.ipv6.routes.FlowspecRoute;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpReachNlri;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpReachNlriBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpUnreachNlri;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpUnreachNlriBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.mp.reach.nlri.AdvertizedRoutesBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.mp.unreach.nlri.WithdrawnRoutesBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.Route;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.tables.Routes;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.next.hop.CNextHop;
import org.opendaylight.yangtools.yang.binding.DataObject;
import org.opendaylight.yangtools.yang.common.QName;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
import org.opendaylight.yangtools.yang.data.api.schema.DataContainerNode;
import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.DataContainerNodeAttrBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.DataContainerNodeBuilder;

public abstract class AbstractFlowspecRIBSupport extends AbstractRIBSupport {

    protected abstract static class ApplyRoute {
        abstract void apply(DOMDataWriteTransaction tx, YangInstanceIdentifier base, NodeIdentifierWithPredicates routeKey, DataContainerNode<?> route, final ContainerNode attributes);
    }

    protected static final class DeleteRoute extends ApplyRoute {
        @Override
        void apply(final DOMDataWriteTransaction tx, final YangInstanceIdentifier base, final NodeIdentifierWithPredicates routeKey, final DataContainerNode<?> route, final ContainerNode attributes) {
            tx.delete(LogicalDatastoreType.OPERATIONAL, base.node(routeKey));
        }
    }

    protected final class PutRoute extends ApplyRoute {
        @Override
        void apply(final DOMDataWriteTransaction tx, final YangInstanceIdentifier base, final NodeIdentifierWithPredicates routeKey,
            final DataContainerNode<?> route, final ContainerNode attributes) {
            final DataContainerNodeBuilder<NodeIdentifierWithPredicates, MapEntryNode> b = ImmutableNodes.mapEntryBuilder();
            b.withNodeIdentifier(routeKey);

            // FIXME: All route children, there should be a utility somewhere to do this
            for (final DataContainerChild<? extends PathArgument, ?> child : route.getValue()) {
                b.withChild(child);
            }
            // Add attributes
            final DataContainerNodeAttrBuilder<NodeIdentifier, ContainerNode> cb = Builders.containerBuilder(attributes);
            cb.withNodeIdentifier(routeAttributesIdentifier());
            b.withChild(cb.build());
            tx.put(LogicalDatastoreType.OPERATIONAL, base.node(routeKey), b.build());
        }
    }

    private static final QName ROUTE_KEY = QName.create(FlowspecRoute.QNAME, "route-key").intern();
    private static final ApplyRoute DELETE_ROUTE = new DeleteRoute();
    private final ApplyRoute putRoute = new PutRoute();

    protected AbstractFlowspecRIBSupport(final Class<? extends Routes> cazeClass, final Class<? extends DataObject> containerClass,
        final Class<? extends Route> listClass) {
        super(cazeClass, containerClass, listClass);
    }

    protected abstract NodeIdentifier routeIdentifier();

    protected abstract AbstractFlowspecNlriParser getParser();

    protected abstract Class<? extends AddressFamily> getAfiClass();

    @Override
    public final ImmutableCollection<Class<? extends DataObject>> cacheableAttributeObjects() {
        return ImmutableSet.of();
    }

    @Override
    public final ImmutableCollection<Class<? extends DataObject>> cacheableNlriObjects() {
        return ImmutableSet.of();
    }

    @Override
    public final boolean isComplexRoute() {
        return true;
    }

    @Override
    protected final void putDestinationRoutes(final DOMDataWriteTransaction tx, final YangInstanceIdentifier tablePath,
        final ContainerNode destination, final ContainerNode attributes, final NodeIdentifier routesNodeId) {
        processDestination(tx, tablePath.node(routesNodeId), destination, attributes, this.putRoute);
    }

    @Override
    protected final void deleteDestinationRoutes(final DOMDataWriteTransaction tx, final YangInstanceIdentifier tablePath,
        final ContainerNode destination, final NodeIdentifier routesNodeId) {
        processDestination(tx, tablePath.node(routesNodeId), destination, null, DELETE_ROUTE);
    }

    private void processDestination(final DOMDataWriteTransaction tx, final YangInstanceIdentifier routesPath,
        final ContainerNode destination, final ContainerNode attributes, final ApplyRoute function) {
        if (destination != null) {
            final YangInstanceIdentifier base = routesPath.node(routesContainerIdentifier()).node(routeIdentifier());
            final NodeIdentifierWithPredicates routeKey = new NodeIdentifierWithPredicates(FlowspecRoute.QNAME, ROUTE_KEY, getParser().stringNlri(destination));
            function.apply(tx, base, routeKey,  destination, attributes);
        }
    }

    @Override
    protected final MpReachNlri buildReach(final Collection<MapEntryNode> routes, final CNextHop hop) {
        final MpReachNlriBuilder mb = new MpReachNlriBuilder();
        mb.setAfi(getAfiClass());
        mb.setSafi(FlowspecSubsequentAddressFamily.class);
        mb.setCNextHop(hop);

        mb.setAdvertizedRoutes(new AdvertizedRoutesBuilder().setDestinationType(
            getParser().createAdvertizedRoutesDestinationType(
                getParser().extractFlowspec(Iterables.getOnlyElement(routes)))).build());
        return mb.build();
    }

    @Override
    protected final MpUnreachNlri buildUnreach(final Collection<MapEntryNode> routes) {
        final MpUnreachNlriBuilder mb = new MpUnreachNlriBuilder();
        mb.setAfi(getAfiClass());
        mb.setSafi(FlowspecSubsequentAddressFamily.class);

        mb.setWithdrawnRoutes(new WithdrawnRoutesBuilder().setDestinationType(
            getParser().createWithdrawnDestinationType(
                getParser().extractFlowspec(Iterables.getOnlyElement(routes)))).build());
        return mb.build();
    }
}