FifoLpcDataFetcher.java

/*
  FifoLpcDataFetcher.java

  (c) 2012-2013 Edward Swartz

  All rights reserved. This program and the accompanying materials
  are made available under the terms of the Eclipse Public License v1.0
  which accompanies this distribution, and is available at
  http://www.eclipse.org/legal/epl-v10.html
 */
package v9t9.engine.speech;

import ejs.base.properties.IProperty;
import ejs.base.settings.Logging;
import ejs.base.utils.BinaryUtils;
import ejs.base.utils.HexUtils;

/**
 * Read LPC data from a FIFO
 * @author ejs
 *
 */
public class FifoLpcDataFetcher extends BaseFifoLpcDataFetcher  {
	
	private byte fifo[]	= new byte[16]; /* fifo buffer */
	private int out, in; /* ptrs. out==in --> empty */
	private int len; /* # bytes in buffer */
	private IProperty logProperty;
	public FifoLpcDataFetcher() {
		setByteFetcher(this);
		
	}
	
	
	public void setLogProperty(IProperty property) {
		this.logProperty = property;
	}
	
	/**
	 * 
	 */
	public synchronized void purge() {
		bit = 0;
		out = in = len = 0;
		
		if (listener != null)
			listener.lengthChanged(len);
	}

	public synchronized void write(byte val) {
		fifo[in] = BinaryUtils.swapBits(val);
		in = (in + 1) & 15;
		
		if (logProperty != null) {
			Logging.writeLogLine(3, logProperty,
				"FIFO write: " + HexUtils.toHex2(val) + "; len = " + len);
			if (len == 16) {
				Logging.writeLogLine(1, logProperty,
						"FIFO OVERFLOW!");
			}
		}
		
		if (len < 16) {
			len++;
		} 
		
		if (listener != null)
			listener.lengthChanged(len);

	}
	
	@Override
	public synchronized byte read() {
		byte ret = fifo[out];
		
		Logging.writeLogLine(3, logProperty, "FIFO read: " + HexUtils.toHex2(ret)
				+ " (was: " + HexUtils.toHex2(BinaryUtils.swapBits(ret)) + ")"
				+ "; len = " + len);


		if (len == 0) {
			if (listener != null) {
				listener.fetchedEmpty();
			}
		}
		if (len > 0) {
			out = (out + 1) & 15;
			len--;
			
			if (listener != null) {
				listener.lengthChanged(len);
			}
		}
		
		return ret;
	}

	@Override
	public synchronized byte peek() {
		return fifo[out];
	}

	/* (non-Javadoc)
	 * @see v9t9.engine.speech.IFifoLpcDataFetcher#isFull()
	 */
	@Override
	public synchronized boolean isFull() {
		return len == fifo.length;
	}
}