package com.trilead.ssh2.packets;

import java.io.IOException;

/**
 * PacketServiceAccept.
 *
 * @author Christian Plattner, plattner@trilead.com
 * @version $Id: PacketServiceAccept.java,v 1.2 2008/04/01 12:38:09 cplattne Exp $
 */
public class PacketServiceAccept {
    byte[] payload;

    String serviceName;

    public PacketServiceAccept(String serviceName) {
        this.serviceName = serviceName;
    }

    public PacketServiceAccept(byte payload[], int off, int len) throws IOException {
        this.payload = new byte[len];
        System.arraycopy(payload, off, this.payload, 0, len);
        TypesReader tr = new TypesReader(payload, off, len);
        int packet_type = tr.readByte();

        if (packet_type != Packets.SSH_MSG_SERVICE_ACCEPT)
            throw new IOException("This is not a SSH_MSG_SERVICE_ACCEPT! (" + packet_type + ")");

        /* Be clever in case the server is not. Some servers seem to violate RFC4253 */

        if (tr.remain() > 0) {
            serviceName = tr.readString();
        }
        else {
            serviceName = "";
        }

        if (tr.remain() != 0)
            throw new IOException("Padding in SSH_MSG_SERVICE_ACCEPT packet!");
    }

    public byte[] getPayload() {
        if (payload == null) {
            TypesWriter tw = new TypesWriter();
            tw.writeByte(Packets.SSH_MSG_SERVICE_ACCEPT);
            tw.writeString(serviceName);
            payload = tw.getBytes();
        }

        return payload;
    }
}