/*
 * GNU LESSER GENERAL PUBLIC LICENSE Copyright (C) 2006 The Lobo Project
 * 
 * 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 2.1 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.,
 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 * 
 * Contact info: lobochief@users.sourceforge.net
 */
/*
 * Created on Apr 15, 2005
 */
package com.nvarghese.beowulf.common.cobra.util;

import java.io.IOException;
import java.io.InputStream;

/**
 * @author J. H. S.
 */
public class MonitoredInputStream extends InputStream {

	private final InputStream delegate;
	private int progress = 0;
	private final long minProgressEventGap;
	public final EventDispatch evtProgress = new EventDispatch();

	public MonitoredInputStream(final InputStream delegate, final int minProgressEventGap) {

		this.delegate = delegate;
		this.minProgressEventGap = minProgressEventGap;
	}

	public MonitoredInputStream(final InputStream delegate) {

		this(delegate, 200);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.io.InputStream#available()
	 */
	public int available() throws IOException {

		return this.delegate.available();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.io.InputStream#close()
	 */
	public void close() throws IOException {

		this.delegate.close();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.io.InputStream#markSupported()
	 */
	public boolean markSupported() {

		return false;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.io.InputStream#read()
	 */
	public int read() throws IOException {

		int b = this.delegate.read();
		if (b != -1) {
			this.progress++;
		}
		return b;
	}

	private long lastEvenPosted = 0;

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.io.InputStream#read(byte[], int, int)
	 */
	public int read(final byte[] arg0, final int arg1, final int arg2) throws IOException {

		int numRead = this.delegate.read(arg0, arg1, arg2);
		if (numRead != -1) {
			this.progress += numRead;
			long currentTime = System.currentTimeMillis();
			if (currentTime - this.lastEvenPosted > this.minProgressEventGap) {
				this.evtProgress.fireEvent(new InputProgressEvent(this, this.progress));
				this.lastEvenPosted = currentTime;
			}
		}
		return numRead;
	}
}