/*
 * Copyright (c) 2016 Cisco and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.fd.hc2vpp.routing.read;

import com.google.common.base.Optional;
import io.fd.hc2vpp.common.translate.util.NamingContext;
import io.fd.hc2vpp.routing.trait.RouteMapper;
import io.fd.honeycomb.translate.ModificationCache;
import io.fd.honeycomb.translate.read.ReadContext;
import io.fd.honeycomb.translate.read.ReadFailedException;
import io.fd.honeycomb.translate.spi.read.ListReaderCustomizer;
import io.fd.honeycomb.translate.util.read.cache.DumpCacheManager;
import io.fd.vpp.jvpp.core.dto.Ip6FibDetailsReplyDump;
import io.fd.vpp.jvpp.core.dto.IpFibDetailsReplyDump;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import javax.annotation.Nonnull;
import org.opendaylight.yang.gen.v1.http.fd.io.hc2vpp.yang.vpp.routing.rev180319.RoutingProtocolVppAttr;
import org.opendaylight.yang.gen.v1.http.fd.io.hc2vpp.yang.vpp.routing.rev180319.RoutingProtocolVppAttrBuilder;
import org.opendaylight.yang.gen.v1.http.fd.io.hc2vpp.yang.vpp.routing.rev180319.routing.control.plane.protocols.control.plane.protocol.VppProtocolAttributesBuilder;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.routing.rev180313.Static;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.routing.rev180313.routing.ControlPlaneProtocolsBuilder;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.routing.rev180313.routing.control.plane.protocols.ControlPlaneProtocol;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.routing.rev180313.routing.control.plane.protocols.ControlPlaneProtocolBuilder;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.routing.rev180313.routing.control.plane.protocols.ControlPlaneProtocolKey;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.fib.table.management.rev180521.VniReference;
import org.opendaylight.yangtools.concepts.Builder;
import org.opendaylight.yangtools.yang.binding.DataObject;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;

final class ControlPlaneProtocolCustomizer
        implements ListReaderCustomizer<ControlPlaneProtocol, ControlPlaneProtocolKey, ControlPlaneProtocolBuilder>,
        RouteMapper {

    private final NamingContext routingProtocolContext;
    private final DumpCacheManager<IpFibDetailsReplyDump, Void> ipv4RoutesDumpManager;
    private final DumpCacheManager<Ip6FibDetailsReplyDump, Void> ipv6RoutesDumpManager;


    ControlPlaneProtocolCustomizer(@Nonnull final NamingContext routingProtocolContext,
                                   @Nonnull final DumpCacheManager<IpFibDetailsReplyDump, Void> ipv4RoutesDumpManager,
                                   @Nonnull final DumpCacheManager<Ip6FibDetailsReplyDump, Void> ipv6RoutesDumpManager) {
        this.routingProtocolContext = routingProtocolContext;
        this.ipv4RoutesDumpManager = ipv4RoutesDumpManager;
        this.ipv6RoutesDumpManager = ipv6RoutesDumpManager;
    }

    @Nonnull
    @Override
    public List<ControlPlaneProtocolKey> getAllIds(@Nonnull final InstanceIdentifier<ControlPlaneProtocol> instanceIdentifier,
                                                   @Nonnull final ReadContext readContext) throws ReadFailedException {

        final ModificationCache modificationCache = readContext.getModificationCache();

        // builds keys from routing protocol prefix and unique set of table ids
        return Stream.of(
                ipv4TableIds(instanceIdentifier, modificationCache),
                ipv6TableIds(instanceIdentifier, modificationCache))
                .flatMap(Collection::stream)
                .map(tableId -> routingProtocolContext.getName(tableId, readContext.getMappingContext()))
                .distinct()
                .map(name -> new ControlPlaneProtocolKey(name, Static.class))
                .collect(Collectors.toList());
    }

    private List<Integer> ipv4TableIds(final InstanceIdentifier<ControlPlaneProtocol> instanceIdentifier,
                                       final ModificationCache modificationCache) throws ReadFailedException {
        final Optional<IpFibDetailsReplyDump>
                ipv4Routes = ipv4RoutesDumpManager.getDump(instanceIdentifier, modificationCache);

        if (ipv4Routes.isPresent()) {
            return ipv4Routes.get().ipFibDetails.stream()
                    .map(ipFibDetails -> ipFibDetails.tableId)
                    .collect(Collectors.toList());
        }
        return Collections.emptyList();
    }

    private List<Integer> ipv6TableIds(final InstanceIdentifier<ControlPlaneProtocol> instanceIdentifier,
                                       final ModificationCache modificationCache) throws ReadFailedException {
        final Optional<Ip6FibDetailsReplyDump>
                ipv6Routes = ipv6RoutesDumpManager.getDump(instanceIdentifier, modificationCache);

        if (ipv6Routes.isPresent()) {
            return ipv6Routes.get().ip6FibDetails.stream()
                    .map(ipFibDetails -> ipFibDetails.tableId)
                    .collect(Collectors.toList());
        }
        return Collections.emptyList();
    }

    @Override
    public void merge(@Nonnull final Builder<? extends DataObject> builder,
                      @Nonnull final List<ControlPlaneProtocol> list) {
        ((ControlPlaneProtocolsBuilder) builder).setControlPlaneProtocol(list);
    }

    @Nonnull
    @Override
    public ControlPlaneProtocolBuilder getBuilder(@Nonnull final InstanceIdentifier<ControlPlaneProtocol> instanceIdentifier) {
        return new ControlPlaneProtocolBuilder();
    }

    @Override
    public void readCurrentAttributes(@Nonnull final InstanceIdentifier<ControlPlaneProtocol> instanceIdentifier,
                                      @Nonnull final ControlPlaneProtocolBuilder routingProtocolBuilder,
                                      @Nonnull final ReadContext readContext) throws ReadFailedException {
        final ControlPlaneProtocolKey key = instanceIdentifier.firstKeyOf(ControlPlaneProtocol.class);
        routingProtocolBuilder
            .setName(key.getName())
            .withKey(key)
            .setType(Static.class)
            .addAugmentation(RoutingProtocolVppAttr.class, new RoutingProtocolVppAttrBuilder().setVppProtocolAttributes(
                new VppProtocolAttributesBuilder()
                    .setPrimaryVrf(
                        new VniReference(
                            Long.valueOf(routingProtocolContext.getIndex(key.getName(),
                                                                         readContext.getMappingContext()))))
                        // address family is not being set because Control plane protocol can contain both IPv4 and IPv6
                        // protocols. Address family is resolved by static route type.
                    .build())
                .build())
            .build();
    }
}