/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.cassandra.locator;

import java.io.Serializable;
import java.net.InetAddress;
import java.net.UnknownHostException;

import com.google.common.base.Preconditions;
import com.google.common.net.HostAndPort;

import org.apache.cassandra.utils.FBUtilities;
import org.apache.cassandra.utils.FastByteOperations;

A class to replace the usage of InetAddress to identify hosts in the cluster.
Opting for a full replacement class so that in the future if we change the nature
of the identifier the refactor will be easier in that we don't have to change the type
just the methods.
Because an IP might contain multiple C* instances the identification must be done
using the IP + port. InetSocketAddress is undesirable for a couple of reasons. It's not comparable,
it's toString() method doesn't correctly bracket IPv6, it doesn't handle optional default values,
and a couple of other minor behaviors that are slightly less troublesome like handling the
need to sometimes return a port and sometimes not.
/**
 * A class to replace the usage of InetAddress to identify hosts in the cluster.
 * Opting for a full replacement class so that in the future if we change the nature
 * of the identifier the refactor will be easier in that we don't have to change the type
 * just the methods.
 *
 * Because an IP might contain multiple C* instances the identification must be done
 * using the IP + port. InetSocketAddress is undesirable for a couple of reasons. It's not comparable,
 * it's toString() method doesn't correctly bracket IPv6, it doesn't handle optional default values,
 * and a couple of other minor behaviors that are slightly less troublesome like handling the
 * need to sometimes return a port and sometimes not.
 *
 */
public final class InetAddressAndPort implements Comparable<InetAddressAndPort>, Serializable
{
    private static final long serialVersionUID = 0;

    //Store these here to avoid requiring DatabaseDescriptor to be loaded. DatabaseDescriptor will set
    //these when it loads the config. A lot of unit tests won't end up loading DatabaseDescriptor.
    //Tools that might use this class also might not load database descriptor. Those tools are expected
    //to always override the defaults.
    static volatile int defaultPort = 7000;

    public final InetAddress address;
    public final byte[] addressBytes;
    public final int port;

    private InetAddressAndPort(InetAddress address, byte[] addressBytes, int port)
    {
        Preconditions.checkNotNull(address);
        Preconditions.checkNotNull(addressBytes);
        validatePortRange(port);
        this.address = address;
        this.port = port;
        this.addressBytes = addressBytes;
    }

    private static void validatePortRange(int port)
    {
        if (port < 0 | port > 65535)
        {
            throw new IllegalArgumentException("Port " + port + " is not a valid port number in the range 0-65535");
        }
    }

    @Override
    public boolean equals(Object o)
    {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        InetAddressAndPort that = (InetAddressAndPort) o;

        if (port != that.port) return false;
        return address.equals(that.address);
    }

    @Override
    public int hashCode()
    {
        int result = address.hashCode();
        result = 31 * result + port;
        return result;
    }

    @Override
    public int compareTo(InetAddressAndPort o)
    {
        int retval = FastByteOperations.compareUnsigned(addressBytes, 0, addressBytes.length, o.addressBytes, 0, o.addressBytes.length);
        if (retval != 0)
        {
            return retval;
        }

        return Integer.compare(port, o.port);
    }

    public String getHostAddress(boolean withPort)
    {
        if (withPort)
        {
            return toString();
        }
        else
        {
            return address.getHostAddress();
        }
    }

    @Override
    public String toString()
    {
        return toString(true);
    }

    public String toString(boolean withPort)
    {
        if (withPort)
        {
            return HostAndPort.fromParts(address.getHostAddress(), port).toString();
        }
        else
        {
            return address.toString();
        }
    }

    public static InetAddressAndPort getByName(String name) throws UnknownHostException
    {
        return getByNameOverrideDefaults(name, null);
    }

    
Params:
name – Hostname + optional ports string
port – Port to connect on, overridden by values in hostname string, defaults to DatabaseDescriptor default if not specified anywhere.
Throws:
UnknownHostException – 
Returns:
/**
     *
     * @param name Hostname + optional ports string
     * @param port Port to connect on, overridden by values in hostname string, defaults to DatabaseDescriptor default if not specified anywhere.
     * @return
     * @throws UnknownHostException
     */
    public static InetAddressAndPort getByNameOverrideDefaults(String name, Integer port) throws UnknownHostException
    {
        HostAndPort hap = HostAndPort.fromString(name);
        if (hap.hasPort())
        {
            port = hap.getPort();
        }
        return getByAddressOverrideDefaults(InetAddress.getByName(hap.getHostText()), port);
    }

    public static InetAddressAndPort getByAddress(byte[] address) throws UnknownHostException
    {
        return getByAddressOverrideDefaults(InetAddress.getByAddress(address), address, null);
    }

    public static InetAddressAndPort getByAddress(InetAddress address)
    {
        return getByAddressOverrideDefaults(address, null);
    }

    public static InetAddressAndPort getByAddressOverrideDefaults(InetAddress address, Integer port)
    {
        if (port == null)
        {
            port = defaultPort;
        }

        return new InetAddressAndPort(address, address.getAddress(), port);
    }

    public static InetAddressAndPort getByAddressOverrideDefaults(InetAddress address, byte[] addressBytes, Integer port)
    {
        if (port == null)
        {
            port = defaultPort;
        }

        return new InetAddressAndPort(address, addressBytes, port);
    }

    public static void initializeDefaultPort(int port)
    {
        defaultPort = port;
    }
}