/**************************************************************
 * 
 * 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 com.sun.star.lib.connections.socket;


import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;

import java.net.Socket;

import java.util.Enumeration;
import java.util.Vector;


import com.sun.star.io.XStreamListener;

import com.sun.star.connection.XConnection;
import com.sun.star.connection.XConnectionBroadcaster;

/**
 * The SocketConnection implements the <code>XConnection</code> interface
 * and is uses by the <code>SocketConnector</code> and the <code>SocketAcceptor</code>.
 * This class is not part of the provided <code>api</code>.
 * <p>
 * @version 	$Revision: 1.6 $ $ $Date: 2008-04-11 11:14:31 $
 * @author 	    Kay Ramme
 * @see         com.sun.star.comp.connections.SocketAcceptor
 * @see         com.sun.star.comp.connections.SocketConnector
 * @see         com.sun.star.connections.XConnection
 * @since       UDK1.0
 */
public class SocketConnection implements XConnection, XConnectionBroadcaster {
	/**
	 * When set to true, enables various debugging output.
	 */
	static public final boolean DEBUG = false;

	protected String       _description;
	protected Socket       _socket;
	protected InputStream  _inputStream;
	protected OutputStream _outputStream;
	protected Vector       _listeners;
	protected boolean      _firstRead;

	/**
	 * Constructs a new <code>SocketConnection</code>.
	 * <p>
	 * @param  description   the description of the connection
	 * @param  socket        the socket of the connection
	 */
	public SocketConnection(String description, Socket socket) throws IOException {
		if (DEBUG) System.err.println("##### " + getClass().getName() + " - instantiated " + description + " " + socket);

		_description = description
			+ ",localHost=" + socket.getLocalAddress().getHostName()
			+ ",localPort=" + socket.getLocalPort()
			+ ",peerHost=" + socket.getInetAddress().getHostName()
			+ ",peerPort=" + socket.getPort();

		_socket = socket;
		_inputStream = new BufferedInputStream(socket.getInputStream());
		_outputStream = new BufferedOutputStream(socket.getOutputStream());

		_listeners = new Vector();
		_firstRead = true;
	}


    public void addStreamListener(XStreamListener aListener ) throws com.sun.star.uno.RuntimeException {
		_listeners.addElement(aListener);
	}

    public void removeStreamListener(XStreamListener aListener ) throws com.sun.star.uno.RuntimeException {
		_listeners.removeElement(aListener);
	}

	private void notifyListeners_open() {
		Enumeration elements = _listeners.elements();
		while(elements.hasMoreElements()) {
			XStreamListener xStreamListener = (XStreamListener)elements.nextElement();
			xStreamListener.started();
		}
	}

	private void notifyListeners_close() {
		Enumeration elements = _listeners.elements();
		while(elements.hasMoreElements()) {
			XStreamListener xStreamListener = (XStreamListener)elements.nextElement();
			xStreamListener.closed();
		}
	}
	
	private void notifyListeners_error(com.sun.star.uno.Exception exception) {
		Enumeration elements = _listeners.elements();
		while(elements.hasMoreElements()) {
			XStreamListener xStreamListener = (XStreamListener)elements.nextElement();
			xStreamListener.error(exception);
		}
	}


	/**
	 * Read the required number of bytes.
	 * <p>
	 * @return   the number of bytes read
	 * @param    aReadBytes   the outparameter, where the bytes have to be placed
	 * @param    nBytesToRead the number of bytes to read
     * @see       com.sun.star.connections.XConnection#read
	 */
    public int read(/*OUT*/byte[][] bytes, int nBytesToRead) throws com.sun.star.io.IOException, com.sun.star.uno.RuntimeException {
		if(_firstRead) {
			_firstRead = false;

			notifyListeners_open();
		}

		String errMessage = null;

		int read_bytes = 0;
		bytes[0] = new byte[nBytesToRead];

		try {
			int count  ;

			do {
				count = _inputStream.read(bytes[0], read_bytes, nBytesToRead - read_bytes);
				if(count == -1)
					errMessage = "EOF reached - " + getDescription();

				read_bytes += count;
			}
			while(read_bytes >= 0 && read_bytes < nBytesToRead && count >= 0);
		}
		catch(IOException ioException) {
			if(DEBUG) {
				System.err.println("##### " + getClass().getName() + ".read - exception occurred:" + ioException);
				ioException.printStackTrace();
			}

			errMessage = ioException.toString();
		}

		if(errMessage != null) {
			com.sun.star.io.IOException unoIOException = new com.sun.star.io.IOException(errMessage);
			notifyListeners_error(unoIOException);

			throw unoIOException;
		}

		if (DEBUG) System.err.println("##### " + getClass().getName() + " - read byte:" + read_bytes + " " + bytes[0]);

		return read_bytes;
	}

	/**
	 * Write bytes.
	 * <p>
	 * @param    aData the bytes to write
     * @see       com.sun.star.connections.XConnection#write
	 */
    public void write(byte aData[]) throws com.sun.star.io.IOException, com.sun.star.uno.RuntimeException {
		try {
			_outputStream.write(aData);
		}
		catch(IOException ioException) {
			com.sun.star.io.IOException unoIOException = new com.sun.star.io.IOException(ioException.toString());
			notifyListeners_error(unoIOException);

			throw unoIOException;
		}

		if (DEBUG) System.err.println("##### " + getClass().getName() + " - written bytes:" + aData + " " + aData.length);
	}

	/**
	 * Flushes the buffer.
	 * <p>
     * @see       com.sun.star.connections.XConnection#flush
	 */
    public void flush() throws com.sun.star.io.IOException, com.sun.star.uno.RuntimeException {
		try {
			_outputStream.flush();
		}
		catch(IOException ioException) {
			com.sun.star.io.IOException unoIOException = new com.sun.star.io.IOException(ioException.toString());
			notifyListeners_error(unoIOException);

			throw unoIOException;
		}
	}

	/**
	 * Closes the connection.
	 * <p>
     * @see       com.sun.star.connections.XConnection#close
	 */
    public void close() throws com.sun.star.io.IOException, com.sun.star.uno.RuntimeException {
		try {
			_socket.close();
		}
		catch(IOException ioException) {
			com.sun.star.io.IOException unoIOException = new com.sun.star.io.IOException(ioException.toString());
			notifyListeners_error(unoIOException);

			throw unoIOException;
		}
		if (DEBUG) System.err.println("##### " + getClass().getName() + " - socket closed");

		notifyListeners_close();
	}

	/**
	 * Gives a description of the connection.
	 * <p>
	 * @return  the description
     * @see       com.sun.star.connections.XConnection#getDescription
	 */
	public String getDescription() throws com.sun.star.uno.RuntimeException {
		return _description;
	}

}