/*
 * Copyright 2017-present Open Networking Foundation
 *
 * 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.dhcprelay.store;

import com.google.common.base.MoreObjects;
import com.google.common.collect.Sets;
import org.onlab.packet.DHCP;
import org.onlab.packet.DHCP6;
import org.onlab.packet.Ip4Address;
import org.onlab.packet.Ip6Address;
import org.onlab.packet.IpPrefix;
import org.onlab.packet.MacAddress;
import org.onlab.packet.VlanId;
import org.onosproject.net.HostId;
import org.onosproject.net.HostLocation;

import java.util.Objects;
import java.util.Optional;
import java.util.Set;

import static com.google.common.base.Preconditions.checkNotNull;

/**
 * A class to record DHCP from DHCP relay application.
 */
public class DhcpRecord {
    private final Set<HostLocation> locations;
    private final MacAddress macAddress;
    private final VlanId vlanId;
    private MacAddress nextHop;
    // this will hold the potential next hop change in case
    // of successfull LQ from another NH for a certain IP
    private MacAddress nextHopTemp;

    private Ip4Address ip4Address;
    private DHCP.MsgType ip4Status;

    private Ip6Address ip6Address;
    private IpPrefix pdPrefix;
    private DHCP6.MsgType ip6Status;

    private long lastSeen;
    private long lastIp6Update;
    private long lastPdUpdate;

    private boolean directlyConnected;
    private long addrPrefTime;
    private long pdPrefTime;
    private DhcpRelayCounters v6Counters;


    /**
     * Creates a DHCP record for a host (mac + vlan).
     *
     * @param hostId the host id for the host
     */
    public DhcpRecord(HostId hostId) {
        checkNotNull(hostId, "Host id can't be null");

        this.locations = Sets.newHashSet();
        this.macAddress = hostId.mac();
        this.vlanId = hostId.vlanId();
        this.lastSeen = System.currentTimeMillis();
        this.directlyConnected = false;
        this.v6Counters = new DhcpRelayCounters();
    }

    /**
     * Gets host locations.
     *
     * @return the locations of host
     */
    public Set<HostLocation> locations() {
        return locations;
    }

    /**
     * Adds a location to record.
     *
     * @param location the location
     * @return the DHCP record
     */
    public DhcpRecord addLocation(HostLocation location) {
        if (locations.contains(location)) {
            locations.remove(location);
        }
        locations.add(location);
        return this;
    }

    /**
     * Removes a location from record.
     *
     * @param location the location
     * @return the DHCP record
     */
    public DhcpRecord removeLocation(HostLocation location) {
        locations.remove(location);
        return this;
    }

    /**
     * Gets host mac address of this record.
     *
     * @return the host mac address
     */
    public MacAddress macAddress() {
        return macAddress;
    }

    /**
     * Gets host vlan id of this record.
     *
     * @return the host id.
     */
    public VlanId vlanId() {
        return vlanId;
    }

    /**
     * Gets IPv4 address which assigned to the host.
     *
     * @return the IP address assigned to the host
     */
    public Optional<Ip4Address> ip4Address() {
        return Optional.ofNullable(ip4Address);
    }

    /**
     * Sets IPv4 address.
     *
     * @param ip4Address the IPv4 address
     * @return the DHCP record
     */
    public DhcpRecord ip4Address(Ip4Address ip4Address) {
        this.ip4Address = ip4Address;
        return this;
    }

    /**
     * Gets IPv6 address which assigned to the host.
     *
     * @return the IP address assigned to the host
     */
    public Optional<Ip6Address> ip6Address() {
        return Optional.ofNullable(ip6Address);
    }

    /**
     * Sets IPv6 address.
     *
     * @param ip6Address the IPv6 address
     * @return the DHCP record
     */
    public DhcpRecord ip6Address(Ip6Address ip6Address) {
        this.ip6Address = ip6Address;
        return this;
    }

    /**
     * Gets IPv6 PD address which assigned to the host.
     *
     * @return the PD IP address assigned to the host
     */
    public Optional<IpPrefix> pdPrefix() {
        return Optional.ofNullable(pdPrefix);
    }

    /**
     * Sets IPv6 PD address.
     *
     * @param pdPrefix the IPv6 PD address
     * @return the DHCP record
     */
    public DhcpRecord pdPrefix(IpPrefix pdPrefix) {
        this.pdPrefix = pdPrefix;
        return this;
    }

    /**
     * Gets the latest time this record updated.
     *
     * @return the last time host send or receive DHCP packet
     */
    public long lastSeen() {
        return lastSeen;
    }

    /**
     * Updates the update time of this record.
     *
     * @return the DHCP record
     */
    public DhcpRecord updateLastSeen() {
        lastSeen = System.currentTimeMillis();
        return this;
    }

    /**
     * Gets the latest time this record updated with ip6 Address.
     *
     * @return the last time received DHCP packet provide ip6 Address
     */
    public long getLastIp6Update() {
        return lastIp6Update;
    }

    /**
     * Updates the update time of this record is given ip6 Address.
     *
     * @return the DHCP record
     */
    public DhcpRecord updateLastIp6Update() {
        lastIp6Update = System.currentTimeMillis();
        return this;
    }

    /**
     * Gets the latest time this record updated with pd Prefix.
     *
     * @return the last time received DHCP packet provide pd Prefix
     */
    public long getLastPdUpdate() {
        return lastPdUpdate;
    }

    /**
     * Updates the update time of this record is given pd Prefix.
     *
     * @return the DHCP record
     */
    public DhcpRecord updateLastPdUpdate() {
        lastPdUpdate = System.currentTimeMillis();
        return this;
    }

    /**
     * Gets the IP Address preferred time for this record.
     *
     * @return the preferred lease time for this ip address
     */
    public long addrPrefTime() {
        return addrPrefTime;
    }

    /**
     * Updates the IP Address preferred time of this record.
     *
     * @param prefTime preferred liftme
     * @return the DHCP record
     */
    public DhcpRecord updateAddrPrefTime(long prefTime) {
        addrPrefTime = prefTime;
        return this;
    }

    /**
     * Gets the PD Prefix preferred time for this record.
     *
     * @return the preferred lease time for this PD prefix
     */
    public long pdPrefTime() {
        return pdPrefTime;
    }

    /**
     * Updates the PD Prefix preferred time of this record.
     *
     * @param prefTime preferred liftme
     * @return the DHCP record
     */
    public DhcpRecord updatePdPrefTime(long prefTime) {
        pdPrefTime = prefTime;
        return this;
    }

    /**
     * Indicated that the host is direct connected to the network or not.
     *
     * @return true if the host is directly connected to the network; false otherwise
     */
    public boolean directlyConnected() {
        return directlyConnected;
    }

    /**
     * Sets the flag which indicated that the host is directly connected to the
     * network.
     *
     * @param directlyConnected the flag to set
     * @return the DHCP record
     */
    public DhcpRecord setDirectlyConnected(boolean directlyConnected) {
        this.directlyConnected = directlyConnected;
        return this;
    }

    /**
     * Gets the DHCPv4 status of this record.
     *
     * @return the DHCPv4 status; empty if not exists
     */
    public Optional<DHCP.MsgType> ip4Status() {
        return Optional.ofNullable(ip4Status);
    }

    /**
     * Sets status of DHCPv4.
     *
     * @param ip4Status the status
     * @return the DHCP record
     */
    public DhcpRecord ip4Status(DHCP.MsgType ip4Status) {
        this.ip4Status = ip4Status;
        return this;
    }

    /**
     * Gets the DHCPv6 status of this record.
     *
     * @return the DHCPv6 status; empty if not exists
     */
    public Optional<DHCP6.MsgType> ip6Status() {
        return Optional.ofNullable(ip6Status);
    }

    /**
     * Sets status of DHCPv6.
     *
     * @param ip6Status the DHCPv6 status
     * @return the DHCP record
     */
    public DhcpRecord ip6Status(DHCP6.MsgType ip6Status) {
        this.ip6Status = ip6Status;
        return this;
    }

    /**
     * Gets nextHop mac address.
     *
     * @return the IPv4 nextHop mac address; empty if not exists
     */
    public Optional<MacAddress> nextHop() {
        return Optional.ofNullable(nextHop);
    }

    /**
     * Sets nextHop mac address.
     *
     * @param nextHop the IPv4 nextHop mac address
     * @return the DHCP record
     */
    public DhcpRecord nextHop(MacAddress nextHop) {
        this.nextHop = nextHop;
        return this;
    }

    /**
     * Gets temporary nextHop mac address.
     *
     * @return the IPv4 nextHop mac address; empty if not exists
     */
    public Optional<MacAddress> nextHopTemp() {
        return Optional.ofNullable(nextHopTemp);
    }

    /**
     * Sets temporary nextHop mac address.
     *
     * @param nextHop the IPv4 nextHop mac address
     * @return the DHCP record
     */
    public DhcpRecord nextHopTemp(MacAddress nextHop) {
        this.nextHopTemp = nextHop;
        return this;
    }

    /**
     * Gets dhcp relay counters.
     *
     * @return the counter object
     */
    public DhcpRelayCounters getV6Counters() {
        return v6Counters;
    }

    /**
     * Clone this DHCP record.
     *
     * @return the DHCP record which cloned
     */
    public DhcpRecord clone() {
        DhcpRecord newRecord = new DhcpRecord(HostId.hostId(macAddress, vlanId));
        locations.forEach(newRecord::addLocation);
        newRecord.directlyConnected = directlyConnected;
        newRecord.nextHop = nextHop;
        newRecord.nextHopTemp = nextHopTemp;
        newRecord.ip4Address = ip4Address;
        newRecord.ip4Status = ip4Status;
        newRecord.ip6Address = ip6Address;
        newRecord.pdPrefix = pdPrefix;
        newRecord.ip6Status = ip6Status;
        newRecord.lastSeen = lastSeen;
        newRecord.lastIp6Update = lastIp6Update;
        newRecord.lastPdUpdate = lastPdUpdate;
        newRecord.addrPrefTime = addrPrefTime;
        newRecord.pdPrefTime = pdPrefTime;
        newRecord.v6Counters = v6Counters;
        return newRecord;
    }

    @Override
    public int hashCode() {
        return Objects.hash(locations, macAddress, vlanId, ip4Address, ip4Status,
                nextHop, nextHopTemp, ip6Address, pdPrefix, ip6Status, lastSeen,
                lastIp6Update, lastPdUpdate, addrPrefTime, pdPrefTime, v6Counters);
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (!(obj instanceof DhcpRecord)) {
            return false;
        }
        DhcpRecord that = (DhcpRecord) obj;
        return Objects.equals(locations, that.locations) &&
                Objects.equals(macAddress, that.macAddress) &&
                Objects.equals(vlanId, that.vlanId) &&
                Objects.equals(ip4Address, that.ip4Address) &&
                Objects.equals(ip4Status, that.ip4Status) &&
                Objects.equals(nextHop, that.nextHop) &&
                Objects.equals(nextHopTemp, that.nextHopTemp) &&
                Objects.equals(ip6Address, that.ip6Address) &&
                Objects.equals(pdPrefix, that.pdPrefix) &&
                Objects.equals(ip6Status, that.ip6Status) &&
                Objects.equals(lastSeen, that.lastSeen) &&
                Objects.equals(lastIp6Update, that.lastIp6Update) &&
                Objects.equals(lastPdUpdate, that.lastPdUpdate) &&
                Objects.equals(directlyConnected, that.directlyConnected) &&
                Objects.equals(addrPrefTime, that.addrPrefTime) &&
                Objects.equals(pdPrefTime, that.pdPrefTime) &&
                Objects.equals(v6Counters, that.v6Counters);
    }

    @Override
    public String toString() {
        return MoreObjects.toStringHelper(getClass())
                .add("locations", locations)
                .add("macAddress", macAddress)
                .add("vlanId", vlanId)
                .add("ip4Address", ip4Address)
                .add("ip4State", ip4Status)
                .add("nextHop", nextHop)
                .add("nextHopTemp", nextHopTemp)
                .add("ip6Address", ip6Address)
                .add("pdPrefix", pdPrefix)
                .add("ip6State", ip6Status)
                .add("lastSeen", lastSeen)
                .add("lastIp6Update", lastIp6Update)
                .add("lastPdUpdate", lastPdUpdate)
                .add("directlyConnected", directlyConnected)
                .add("addPrefTime", addrPrefTime)
                .add("pdPrefTime", pdPrefTime)
                .add("v6Counters", v6Counters)
                .toString();
    }
}