package netpaint.messaging;

import java.util.StringTokenizer;

/**
 * Class AdministrativeMessage: This class extends Client Message and
 * is the base for all administrative network messages that will be
 * sent by the client. All of the more specific client message classes
 * will be derived from it and will add more and more spcific
 * functionality onto the basics provided in this class.
 *
 * <PRE>
 * Revision History:
 *     v1.0 (Jan. 29, 2004) - Created the AdministrativeMessage class
 * </PRE>
 *
 * @author <A HREF="mailto:gtg563g@mail.gatech.edu">Daniyar Zhanbekov</A>
 * @version Version 1.0, Jan. 29, 2004
 */

public abstract class AdministrativeMessage extends ClientMessage {
  /**
   * Creates a new <code>AdministrativeMessage</code> instance.
   *
   * @param type a <code>String</code> value
   * @param author a <code>String</code> value
   */
  public AdministrativeMessage(final String type, final String author) {
      super(type, author);
  }

  /**
   * Returns a string representation of the message fit for plain-text
   * transmission over the network.
   *
   * @return a <code>String</code> value
   */
  public final String tokenize() {
    return getMessageType() + ":" + getAuthor();
  }

  /**
   * Parses the string into the specific message.
   *
   * @param message a <code>String</code> value
   * @return an <code>AbstractMessage</code> value
   */
  protected static AbstractMessage parse(final String message) {
    String type = getMessageType(message);
    StringTokenizer st = null;

    if (type == null) {
      return null;
    }

    if (!(type.equals(MessageSettings.JOIN_TYPE)
          || type.equals(MessageSettings.QUIT_TYPE))) {
      return null;
    }

    st = new StringTokenizer(message, ":");

    //Message type:
    if (!st.hasMoreTokens()) { return null; }
    type = st.nextToken();

    //Username:
    if (!st.hasMoreTokens()) { return null; }
    if (type.equals(MessageSettings.JOIN_TYPE)) {
      return new JoinMessage(st.nextToken());
    } else if (type.equals(MessageSettings.QUIT_TYPE)) {
      return new QuitMessage(st.nextToken());
    }

    return null;
  }
}