/*
 *   (C) 2002 Paul Wilkinson  wilko@users.sourceforge.net
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program 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 General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

/*
 * FLAPFrame.java
 *
 * Created on 3 May 2002, 14:51
 */

package com.wilko.jaim;

/**
 * @author paulw
 * @version $Revision: 1.4 $
 */
public abstract class FLAPFrame {

    public static final int FLAP_FRAME_SIGNON = 1;
    public static final int FLAP_FRAME_DATA = 2;
    public static final int FLAP_FRAME_ERROR = 3;
    public static final int FLAP_FRAME_SIGNOFF = 4;
    public static final int FLAP_FRAME_KEEP_ALIVE = 5;
    public static final int FLAP_DATA_OFFSET = 6;

    protected byte[] frame;
    protected int fLen;

    /**
     * Creates new FLAPFrame
     */
    public FLAPFrame() {
        initialise();
    }

    protected void initialise() {
        frame = new byte[8192];
        frame[0] = (byte) '*';
        frame[1] = 0;
        frame[2] = 0;
        frame[3] = 0;
        frame[4] = 0;
        frame[5] = 0;
        fLen = 6;

    }

    public int getSequence() {
        return ((frame[2] & 0xff) * 256 + (frame[3] & 0xff));
    }

    public void setSequence(int sequence) {
        frame[2] = (byte) ((sequence / 256) & 0xff);
        frame[3] = (byte) (sequence & 0xff);
    }

    public int getLength() {
        return ((frame[4] & 0xff) * 256 + (frame[5] & 0xff));
    }

    public void setLength(int length) {
        frame[4] = (byte) (length / 256);
        frame[5] = (byte) (length & 0xff);
        fLen = length + FLAP_DATA_OFFSET;
    }

    public byte[] getFrameData() {
        byte[] b = new byte[fLen];
        System.arraycopy(frame, 0, b, 0, fLen);
        return (b);
    }

    protected void setFrameData(byte[] b) {
        frame = new byte[b.length];
        fLen = b.length;
        System.arraycopy(b, 0, frame, 0, b.length);
    }

    public String toString() {
        StringBuffer temp = new StringBuffer();
        for (int i = 0; i < fLen; i++) {
            int k = frame[i] & 0xff;
            if (k < 16) {
                temp.append("0" + Integer.toHexString(k) + " ");
            } else {
                temp.append(Integer.toHexString(k) + " ");
            }
        }
        return (temp.toString());
    }

    public abstract int getFLAPFrameType();

}