/*
 * Copyright 2016-present Open Networking Laboratory
 *
 * 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 org.onosproject.driver.pipeline;

import org.onlab.packet.MacAddress;
import org.onlab.packet.VlanId;
import org.onosproject.core.ApplicationId;
import org.onosproject.core.DefaultGroupId;
import org.onosproject.net.flow.DefaultTrafficTreatment;
import org.onosproject.net.flow.TrafficSelector;
import org.onosproject.net.flow.TrafficTreatment;
import org.onosproject.net.flow.criteria.Criterion;
import org.onosproject.net.flow.criteria.VlanIdCriterion;
import org.onosproject.net.flow.instructions.Instruction;
import org.onosproject.net.flow.instructions.Instructions;
import org.onosproject.net.flow.instructions.L2ModificationInstruction;
import org.onosproject.net.group.DefaultGroupBucket;
import org.onosproject.net.group.DefaultGroupDescription;
import org.onosproject.net.group.DefaultGroupKey;
import org.onosproject.net.group.GroupBucket;
import org.onosproject.net.group.GroupBuckets;
import org.onosproject.net.group.GroupDescription;
import org.onosproject.net.group.GroupKey;
import org.slf4j.Logger;

import java.util.Collections;

import static org.slf4j.LoggerFactory.getLogger;

/**
 * Group handler for CpqD OFDPA pipeline.
 */
public class CpqdOfdpa2GroupHandler extends Ofdpa2GroupHandler {
    private final Logger log = getLogger(getClass());

    @Override
    protected GroupInfo createL2L3Chain(TrafficTreatment treatment, int nextId,
                                      ApplicationId appId, boolean mpls,
                                      TrafficSelector meta) {
        // for the l2interface group, get vlan and port info
        // for the outer group, get the src/dst mac, and vlan info
        TrafficTreatment.Builder outerTtb = DefaultTrafficTreatment.builder();
        TrafficTreatment.Builder innerTtb = DefaultTrafficTreatment.builder();
        VlanId vlanid = null;
        long portNum = 0;
        boolean setVlan = false, popVlan = false;
        MacAddress srcMac = MacAddress.ZERO;
        MacAddress dstMac = MacAddress.ZERO;
        for (Instruction ins : treatment.allInstructions()) {
            if (ins.type() == Instruction.Type.L2MODIFICATION) {
                L2ModificationInstruction l2ins = (L2ModificationInstruction) ins;
                switch (l2ins.subtype()) {
                    case ETH_DST:
                        dstMac = ((L2ModificationInstruction.ModEtherInstruction) l2ins).mac();
                        outerTtb.setEthDst(dstMac);
                        break;
                    case ETH_SRC:
                        srcMac = ((L2ModificationInstruction.ModEtherInstruction) l2ins).mac();
                        outerTtb.setEthSrc(srcMac);
                        break;
                    case VLAN_ID:
                        vlanid = ((L2ModificationInstruction.ModVlanIdInstruction) l2ins).vlanId();
                        outerTtb.setVlanId(vlanid);
                        setVlan = true;
                        break;
                    case VLAN_POP:
                        innerTtb.popVlan();
                        popVlan = true;
                        break;
                    case DEC_MPLS_TTL:
                    case MPLS_LABEL:
                    case MPLS_POP:
                    case MPLS_PUSH:
                    case VLAN_PCP:
                    case VLAN_PUSH:
                    default:
                        break;
                }
            } else if (ins.type() == Instruction.Type.OUTPUT) {
                portNum = ((Instructions.OutputInstruction) ins).port().toLong();
                innerTtb.add(ins);
            } else {
                log.warn("Driver does not handle this type of TrafficTreatment"
                        + " instruction in nextObjectives:  {}", ins.type());
            }
        }

        if (vlanid == null && meta != null) {
            // use metadata if available
            Criterion vidCriterion = meta.getCriterion(Criterion.Type.VLAN_VID);
            if (vidCriterion != null) {
                vlanid = ((VlanIdCriterion) vidCriterion).vlanId();
            }
            // if vlan is not set, use the vlan in metadata for outerTtb
            if (vlanid != null && !setVlan) {
                outerTtb.setVlanId(vlanid);
            }
        }

        if (vlanid == null) {
            log.error("Driver cannot process an L2/L3 group chain without "
                            + "egress vlan information for dev: {} port:{}",
                    deviceId, portNum);
            return null;
        }

        if (!setVlan && !popVlan) {
            // untagged outgoing port
            TrafficTreatment.Builder temp = DefaultTrafficTreatment.builder();
            temp.popVlan();
            innerTtb.build().allInstructions().forEach(i -> temp.add(i));
            innerTtb = temp;
        }

        // assemble information for ofdpa l2interface group
        int l2groupId = L2_INTERFACE_TYPE | (vlanid.toShort() << 16) | (int) portNum;
        // a globally unique groupkey that is different for ports in the same device,
        // but different for the same portnumber on different devices. Also different
        // for the various group-types created out of the same next objective.
        int l2gk = l2InterfaceGroupKey(deviceId, vlanid, portNum);
        final GroupKey l2groupkey = new DefaultGroupKey(Ofdpa2Pipeline.appKryo.serialize(l2gk));

        // assemble information for outer group
        GroupDescription outerGrpDesc = null;
        if (mpls) {
            // outer group is MPLSInteface
            int mplsInterfaceIndex = getNextAvailableIndex();
            int mplsgroupId = MPLS_INTERFACE_TYPE | (SUBTYPE_MASK & mplsInterfaceIndex);
            final GroupKey mplsgroupkey = new DefaultGroupKey(
                               Ofdpa2Pipeline.appKryo.serialize(mplsInterfaceIndex));
            outerTtb.group(new DefaultGroupId(l2groupId));
            // create the mpls-interface group description to wait for the
            // l2 interface group to be processed
            GroupBucket mplsinterfaceGroupBucket =
                    DefaultGroupBucket.createIndirectGroupBucket(outerTtb.build());
            outerGrpDesc = new DefaultGroupDescription(
                    deviceId,
                    GroupDescription.Type.INDIRECT,
                    new GroupBuckets(Collections.singletonList(
                            mplsinterfaceGroupBucket)),
                    mplsgroupkey,
                    mplsgroupId,
                    appId);
            log.debug("Trying MPLS-Interface: device:{} gid:{} gkey:{} nextid:{}",
                    deviceId, Integer.toHexString(mplsgroupId),
                    mplsgroupkey, nextId);
        } else {
            // outer group is L3Unicast
            int l3unicastIndex = getNextAvailableIndex();
            int l3groupId = L3_UNICAST_TYPE | (TYPE_MASK & l3unicastIndex);
            final GroupKey l3groupkey = new DefaultGroupKey(
                               Ofdpa2Pipeline.appKryo.serialize(l3unicastIndex));
            outerTtb.group(new DefaultGroupId(l2groupId));
            // create the l3unicast group description to wait for the
            // l2 interface group to be processed
            GroupBucket l3unicastGroupBucket =
                    DefaultGroupBucket.createIndirectGroupBucket(outerTtb.build());
            outerGrpDesc = new DefaultGroupDescription(
                    deviceId,
                    GroupDescription.Type.INDIRECT,
                    new GroupBuckets(Collections.singletonList(
                            l3unicastGroupBucket)),
                    l3groupkey,
                    l3groupId,
                    appId);
            log.debug("Trying L3Unicast: device:{} gid:{} gkey:{} nextid:{}",
                    deviceId, Integer.toHexString(l3groupId),
                    l3groupkey, nextId);
        }

        // store l2groupkey with the groupChainElem for the outer-group that depends on it
        GroupChainElem gce = new GroupChainElem(outerGrpDesc, 1, false);
        updatePendingGroups(l2groupkey, gce);

        // create group description for the inner l2interfacegroup
        GroupBucket l2InterfaceGroupBucket =
                DefaultGroupBucket.createIndirectGroupBucket(innerTtb.build());
        GroupDescription l2groupDescription =
                new DefaultGroupDescription(
                        deviceId,
                        GroupDescription.Type.INDIRECT,
                        new GroupBuckets(Collections.singletonList(
                                l2InterfaceGroupBucket)),
                        l2groupkey,
                        l2groupId,
                        appId);
        log.debug("Trying L2Interface: device:{} gid:{} gkey:{} nextId:{}",
                deviceId, Integer.toHexString(l2groupId),
                l2groupkey, nextId);
        return new GroupInfo(l2groupDescription, outerGrpDesc);
    }
}