/**
 * 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.net.InetAddress;
import java.net.UnknownHostException;
import java.util.List;

/**
 * A simple endpoint snitch implementation that assumes rack and dc information is encoded
 * in the ip address.
 */
public class EndPointSnitch extends AbstractEndpointSnitch
{
    public boolean isOnSameRack(InetAddress host, InetAddress host2) 
    {
        /*
         * Look at the IP Address of the two hosts. Compare 
         * the 3rd octet. If they are the same then the hosts
         * are in the same rack else different racks. 
        */
        byte[] ip = host.getAddress();
        byte[] ip2 = host2.getAddress();

        return ip[2] == ip2[2];
    }

    public boolean isInSameDataCenter(InetAddress host, InetAddress host2) 
    {
        /*
         * Look at the IP Address of the two hosts. Compare 
         * the 2nd octet. If they are the same then the hosts
         * are in the same datacenter else different datacenter. 
        */
        byte[] ip = host.getAddress();
        byte[] ip2 = host2.getAddress();

        return ip[1] == ip2[1];
    }

    public String getRack(InetAddress endpoint)
    {
        return "rack1";
    }

    public String getDatacenter(InetAddress endpoint)
    {
        return "dc1";
    }

    @Override
    public List<InetAddress> sortByProximity(final InetAddress address, List<InetAddress> addresses)
    {
        // Optimization to avoid walking the list
        return addresses;
    }

    public int compareEndpoints(InetAddress target, InetAddress a1, InetAddress a2)
    {
        // Making all endpoints equal ensures we won't change the original ordering (since
        // Collections.sort is guaranteed to be stable)
        return 0;
    }

    /* (non-Javadoc)
     * @see org.apache.cassandra.locator.AbstractEndpointSnitch#getLocalDatacenter()
     */
    @Override
    public String getLocalDatacenter()
    {
        return "default-datacenter";
    }

    /* (non-Javadoc)
     * @see org.apache.cassandra.locator.AbstractEndpointSnitch#getLocalRack()
     */
    @Override
    public String getLocalRack()
    {
        return "default-rack";
    }

}