// Copyright 2012 Citrix Systems, Inc. Licensed under the
// Apache License, Version 2.0 (the "License"); you may not use this
// file except in compliance with the License.  Citrix Systems, Inc.
// reserves all rights not expressly granted by 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.
// 
// Automatically generated by addcopyright.py at 04/03/2012
package com.cloud.agent.dhcp;

import java.net.InetAddress;
import java.net.UnknownHostException;

import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentLinkedQueue;

import javax.ejb.Local;
import javax.naming.ConfigurationException;

import org.apache.log4j.Logger;

import com.cloud.agent.api.Answer;
import com.cloud.agent.api.Command;
import com.cloud.utils.Pair;
import com.cloud.utils.net.NetUtils;

@Local(value = { DhcpSnooper.class })
public class FakeDhcpSnooper implements DhcpSnooper {
	private static final Logger s_logger = Logger
			.getLogger(FakeDhcpSnooper.class);
	private Queue<String> _ipAddresses = new ConcurrentLinkedQueue<String>();
	private Map<String, String> _macIpMap = new ConcurrentHashMap<String, String>();
	private Map<String, InetAddress> _vmIpMap = new ConcurrentHashMap<String, InetAddress>();

	@Override
	public boolean configure(String name, Map<String, Object> params)
			throws ConfigurationException {
		String guestIpRange = (String) params.get("guest.ip.range");
		if (guestIpRange != null) {
			String[] guestIps = guestIpRange.split("-");
			if (guestIps.length == 2) {
				long start = NetUtils.ip2Long(guestIps[0]);
				long end = NetUtils.ip2Long(guestIps[1]);
				while (start <= end) {
					_ipAddresses.offer(NetUtils.long2Ip(start++));
				}
			}
		}
		return true;
	}

	@Override
	public boolean start() {
		return true;
	}

	@Override
	public String getName() {
		return "FakeDhcpSnooper";
	}

	@Override
	public InetAddress getIPAddr(String macAddr, String vmName) {
		String ipAddr = _ipAddresses.poll();
		if (ipAddr == null) {
			s_logger.warn("No ip addresses left in queue");
			return null;
		}
		try {
			InetAddress inetAddr = InetAddress.getByName(ipAddr);
			_macIpMap.put(macAddr.toLowerCase(), ipAddr);
			_vmIpMap.put(vmName, inetAddr);
			s_logger.info("Got ip address " + ipAddr + " for vm " + vmName
					+ " mac=" + macAddr.toLowerCase());
			return inetAddr;
		} catch (UnknownHostException e) {
			s_logger.warn("Failed to get InetAddress for " + ipAddr);
			return null;
		}
	}

	@Override
	public void cleanup(String macAddr, String vmName) {
		try {
			if (macAddr == null) {
				return;
			}
			InetAddress inetAddr = _vmIpMap.remove(vmName);
			String ipAddr = inetAddr.getHostName();
			for (Map.Entry<String, String> entry : _macIpMap.entrySet()) {
				if (entry.getValue().equalsIgnoreCase(ipAddr)) {
					macAddr = entry.getKey();
					break;
				}
			}
			ipAddr = _macIpMap.remove(macAddr);

			s_logger.info("Cleaning up for mac address: " + macAddr + " ip="
					+ ipAddr + " inetAddr=" + inetAddr);
			if (ipAddr != null) {
				_ipAddresses.offer(ipAddr);
			}
		} catch (Exception e) {
			s_logger.debug("Failed to cleanup: " + e.toString());
		}
	}

	@Override
	public Map<String, InetAddress> syncIpAddr() {
		return _vmIpMap;
	}

	@Override
	public boolean stop() {
		return false;
	}

	@Override
	public void initializeMacTable(List<Pair<String, String>> macVmNameList) {

	}

	@Override
	public InetAddress getDhcpServerIP() {
		// TODO Auto-generated method stub
		return null;
	}

}