/*
 * Copyright (C) 1999  Jesse E. Peterson
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *
 */

package com.jpeterson.x10server;

import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.jpeterson.pool.SocketObjectPool;
import com.jpeterson.x10client.X10ServerClient;

/**
 * A pool of <CODE>Socket</CODE>'s for <CODE>X10Server</CODE>'s
 * 
 * @author Jesse Peterson (jesse@jpeterson.com)
 * @author Sylvain Maucourt (smaucourt@gmail.com)
 */
public class X10ServerSocketObjectPool extends SocketObjectPool {
	
	private Log logger = LogFactory.getLog(X10ServerSocketObjectPool.class);
	
	/**
	 * Create an object pool of <CODE>Socket</CODE>'s for the specified hostname
	 * and port. Expiration is set to the default value.
	 * 
	 * @param hostname
	 *            Host name or IP address for sockets in the pool.
	 * @param port
	 *            Port for sockets in the pool.
	 */
	public X10ServerSocketObjectPool(String hostname, int port)
			throws UnknownHostException {
		this(InetAddress.getByName(hostname), port, DEFAULT_EXPIRATION);
	}

	/**
	 * Create an object pool of <CODE>Socket</CODE>'s for the specified hostname
	 * and port with the specified expiration.
	 * 
	 * @param hostname
	 *            Host name or IP address for sockets in the pool.
	 * @param port
	 *            Port for sockets in the pool.
	 * @param expiration
	 *            Expiration in milliseconds for sockets in the pool.
	 */
	public X10ServerSocketObjectPool(String hostname, int port, long expiration)
			throws UnknownHostException {
		this(InetAddress.getByName(hostname), port, expiration);
	}

	/**
	 * Create an object pool of <CODE>Socket</CODE>'s for the specified address
	 * and port. Expiration is set to the default value.
	 * 
	 * @param address
	 *            Address for sockets in the pool.
	 * @param port
	 *            Port for sockets in the pool.
	 */
	public X10ServerSocketObjectPool(InetAddress address, int port) {
		this(address, port, DEFAULT_EXPIRATION);
	}

	/**
	 * Create an object pool of <CODE>Socket</CODE>'s for the specified address
	 * and port with the specified expiration.
	 * 
	 * @param address
	 *            Address for sockets in the pool.
	 * @param port
	 *            Port for sockets in the pool.
	 * @param expiration
	 *            Expiration in milliseconds for sockets in the pool.
	 */
	public X10ServerSocketObjectPool(InetAddress address, int port,
			long expiration) {
		super(address, port, expiration);
	}

	/**
	 * Create a new instance of a <CODE>Socket</CODE>.
	 * 
	 * @return A new instance of a <CODE>Socket</CODE> or <CODE>null</CODE> if
	 *         unable to create one.
	 */
	protected Object create() {
		BufferedInputStream x10rsp;
		Socket socket = (Socket) super.create();
		byte[] bytes = new byte[80];
		int count;
		StringBuffer buf = new StringBuffer();

		if (logger.isDebugEnabled()) {
			logger.debug("Creating new X10Server connection.");
		}
		try {
			if (socket != null) {
				// ensure connection is good. Wait for prompt
				x10rsp = new BufferedInputStream(socket.getInputStream());

				do {
					count = x10rsp.read(bytes);

					if (count < 0) {
						// end of connection
						socket = null;
					}
					if (count > 0) {
						buf.append(new String(bytes, 0, count));
					}
				} while ((buf.toString()).indexOf(X10ServerClient.PROMPT) == -1);
			}
		} catch (IOException e) {
			try {
				if (socket != null) {
					socket.close();
				}
			} catch (IOException ex) {
			} finally {
				socket = null;
			}
		}

		return (socket);
	}

	/**
	 * Make sure that the X10Server is still there.
	 * 
	 * @return Always returns <CODE>true</CODE>.
	 */
	protected boolean validate(Object o) {
		Socket socket;
		StringBuffer buf;
		int count;

		if (o instanceof Socket) {
			String command = "\n";
			byte[] bytes = command.getBytes();
			socket = (Socket) o;
			try {
				buf = new StringBuffer();
				OutputStream out = socket.getOutputStream();
				out.write(bytes);
				out.flush();
				InputStream in = socket.getInputStream();
				bytes = new byte[20];
				do {
					if (in.available() == 0) {
						try {
							Thread.sleep(100);
						} catch (InterruptedException e) {
						}
					}
					count = in.read(bytes);
					if (count < 0) {
						// end of stream
						return (false);
					}
					if (count > 0) {
						buf.append(new String(bytes, 0, count));
					}
				} while ((buf.toString()).indexOf("\n>") == -1);
				return (true);
			} catch (IOException e) {
				return (false);
			}
		}
		return (false);
	}
}