/**
 * @(#)gnsd.java      1.0.1 98/12/20
 * <p>
 * Copyright (C) 1998 David E. Wexler
 * <p>
 * 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. See
 * license.txt for a full copy of the GNU GPL.
 * <p>
 * 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.
 * <p>
 * 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.
 * <p>
 * To Contact the author send e-mail to vagabond@netdragon.com or send
 * snailmail to: 511 Bobcat Ct, Punta Gorda, FL 3398.
 */

import java.util.*;
import logger;
import User;
import gnsd;

/**
 * Group - Stores group data and provides fast, easy data exchange between
 * all members.
 * <p>
 * A vector of users is kept for each group and users can join or leave
 * any group that matches their client/gameID.  
 * 
 * @author      David Wexler (vagabond@netdragons.com)
 * @version     1.0.1
 * @since       gnsd.1.0.1
 */


public class Group {
 /**
  * The Users that are in the group.  This allows the server to send them
  * data when require, to remove them from the group, and to keep an
  * accurate user count for this channel.
  */
  private Vector users;

 /**
  * An instance of the primary server.  This is used to perform server
  * level function, such as the removal of groups from the server.
  */
  private gnsd server;

 /**
  * The groups ID.
  */
  private int id;

 /**
  * The client/game ID that can connect to this group.
  */
  private int gameID;

 /**
  * The title or topic of the group.
  */
  private String title;

 /**
  * Information about the state or other group wide information.
  */
  private String mode;

 /**
  * Determins if data should be sent back to the client it came from.
  */
  private boolean toAll = false;

  public boolean useName = true;

 /**
  * Creats and instance of a new group with all the required information.
  * The group starts out empty, and no information is sent to the client
  * about a new group being formed.
  *
  * @param id           the group id
  * @param gID          the Client/Game ID that can use this group
  * @param t            the group title/topic.
  * @param m            the group mode
  * @param s            Instance of the server.
  * @since              gnsd.1.0.1
  */
  public Group (int id, int gID, String t, String m, gnsd s) {
    users = new Vector();
    this.id = id;
    gameID = gID;
    title = t;
    mode = m;
    server = s;
  }

 /**
  * Checks to see if the passed ID is equal to the channel ID.  This is used
  * by the server when checking if a channel with a given ID exists.
  *
  * @param cID          the group ID to check
  * @return             true if cID == id, false otherwise.
  * @see                id
  * @since              gnsd.1.0.1
  */
  public boolean checkID(int cID) {
    return (cID == id);
  }

 /**
  * Checks to see if the passed ID is equal to the channel gameID.  This is
  * used when the server lists channels.  If the game ID's don't match,
  * the channel is not listed.
  *
  * @param gID          the game ID to check
  * @return             true if gID == gameID, false otherwise.
  * @see                gameID
  * @since              gnsd.1.0.1
  */
  public boolean checkGameID(int gID) {
    return (gameID == gID);
  }

 /**
  * Sets the broadcast type.  This allows the client to either request data
  * it sends back, or not.
  *
  * @param b            do we want data back?
  * @see                toAll
  * @since              gnsd.1.0.1
  */
  public void setBroadcastType(boolean b) {
    toAll = b;
  }

 /**
  * Adds a user to the group.  This also sends the join command back to all
  * clients that are in the group.
  *
  * @param u            the user to add
  * @since              gnsd.1.0.1
  */
  public void addUser(User u) {
    users.addElement(u);
    sendAll("@|join|" + u.getUserName() + "`" + u.getID() + "`" +
     u.getMode(), u.getID());
  }

 /**
  * Removes a user from the group.  This also sends the part command back to
  * all the clients taht are in the group.
  *
  * @param u            the user to remove.
  * @since              gnsd.1.0.1
  */
  public void removeUser(User u) {
    sendAll("@|part|" + u.getUserName(), -1);
    users.removeElement(u);
    if (users.size() == 0)
      server.remove(this);
  }

 /**
  * Gets the group ID.
  *
  * @return             the group ID.
  * @see                id
  * @since              gnsd.1.0.1
  */
  public int getID() {
    return id;
  }

 /**
  * Gets the group's title/topic.
  *
  * @return             the group's title.
  * @see                title
  * @since              gnsd.1.0.1
  */
  public String getTitle() {
    return title;
  }

 /**
  * Gets the group's mode.
  *
  * @return             the group's mode.
  * @see                mode
  * @since              gnsd.1.0.1
  */
  public String getMode() {
    return mode;
  }

 /**
  * Displays the name of all the users that are in the group.  They are
  * seperated by a "," so the client can easily pick them appart.
  *
  * @return             a string that list all the users.
  * @since              gnsd.1.0.1
  */
  public String getUserList() {
    String userList = "";
    Enumeration e = users.elements();
    while (e.hasMoreElements ()) {
      User u = (User) e.nextElement();
      userList = userList + "," + u.getUserName() + "`" + u.getID()
       + "`" + u.getMode();
    }
    if (userList.length() > 0)
      return new String(userList.toCharArray(), 1, userList.length()-1);
    else
      return "null";
  }

 /**
  * Gets that data that is sent to the client for the list.  Data is
  * "id`title`mode`userCount".
  *
  * @see                id
  * @see                title
  * @see                mode
  * @since              gnsd.1.0.1
  */
  public String getListData() {
    return "" + id + "`" + title + "`" + mode + "`" + users.size();
  }

 /**
  * Transmits data to all members of the group.  If toAll is set to fall
  * the person who sends the data does not get a copy back.
  *
  * @param data         the message to send
  * @param uID          the user who sent it.
  * @see                toAll
  * @since              gnsd.1.0.1
  */
  public synchronized void sendAll(String data, int uID) {
    synchronized (users) {
      Enumeration e = users.elements();
      while (e.hasMoreElements ()) {
        User u = (User) e.nextElement();
        if (toAll || u.getID() != uID)
          u.send(data);
      }
    }
  }

 /**
  * Sends a private message to only one user of the group.  No Data is
  * ever sent back to the originating client.
  *
  * @param who          the person who is going to get the private message.
  * @param data         the private message
  * @since              gnsd.1.0.1
  */
  public synchronized void sendPriv(String who, String data) {
    synchronized (users) {
      Enumeration e = users.elements();
      while (e.hasMoreElements ()) {
        User u = (User) e.nextElement();
        if (u.getUserName().compareTo(who) == 0)
          u.send("!|" + u.getUserName() + "|" + data);
      }
    }
  }

}