/*
 * FindBugs - Find Bugs in Java programs
 * Copyright (C) 2003-2008 University of Maryland
 * 
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package edu.umd.cs.findbugs.io;

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

public class SlowInputStream extends FilterInputStream {
	private long started = System.currentTimeMillis();

	private long length = 0;

	private int bytesPerSecond;

	public SlowInputStream(InputStream in, int baudRate) {
		super(in);
		this.bytesPerSecond = baudRate / 10;
	}

	private void delay() {
		try {
			long beenRunning = System.currentTimeMillis() - started;
			long time = length * 1000L / bytesPerSecond - beenRunning;
			if (time > 0) {
				Thread.sleep((int) time);
			}
		} catch (InterruptedException e) {
		}
	}

	@Override
    public int read() throws IOException {
		int b = in.read();
		if (b >= 0)
			length++;
		delay();
		return b;
	}

	@Override
    public int read(byte[] b) throws IOException {
		return read(b, 0, b.length);
	}

	@Override
    public int read(byte[] b, int off, int len) throws IOException {
		if (len > bytesPerSecond / 10)
			len = bytesPerSecond / 10;
		int tmp = in.read(b, off, len);
		if (tmp >= 0) {
			length += tmp;
			delay();
		}
		return tmp;
	}

	@Override
    public long skip(long n) throws IOException {
		n = in.skip(n);
		if (n >= 0)
			length += n;
		delay();
		return n;
	}

	@Override
    public void close() throws IOException {
		in.close();
	}
}