package bvyy.database;
// Copyright(C)1998 Brian Yap

// 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., 675 Mass
// Ave, Cambridge, MA 02139, USA.

//import java.lang.*;
import java.util.*;
import java.io.*;
import bvyy.util.*;
import bvyy.command.*;
/**
 * Make a general purpose capability model.
 * <p>
 * <b>Intent</b>
 * <p>
 * This is a capability class. It records the capabilities that a thing may
 * have. These capabilities are organised into multiple trees as required by
 * the game world builder.
 * <p>
 * <b>Motivation</b>
 * <p>
 * Allow the game desingers to specify capabilities that I could not
 * have envisionaged. Maked the game customisable by a non-computer literate
 * author with no need to write code.
 * <p>
 * @version 0.0.2  26 October 1998
 * @author (c) 1998 Brian Voon Yee Yap
 *
 */

public class Capability implements Serializable{

  Vector branches   = new Vector();
  String       name = "No name";
  boolean      root = true;
  Capability parent = null;
  private transient Vector generalEventListeners;
  private Capability parent;
  private Command command;
  private String nounForm;
/**
 * Creates a new root Capability.
 *
 * @param newName The name for this capability.
 */
  public Capability(String newName) {
    name = newName;
  }
/**
 * Creates a new Capability.
 *
 * @param newName The name for this capability.
 * @param myParentCapability The name of the parent capability.
 */
  public Capability(String newName, Capability myParentCapability) {
    name = newName;
    parent = myParentCapability;
    root = false;
  }
/**
 * Test if this capability is the root.
 *
 * @return true if this capability is at the root.
 */
  public boolean getRoot() {
    return root;
  }
/**
 * Sets this node to be a root node.</p> <p>
 * If the parent has been set, then the paret is reset to null.
 *
 */
  public void setRoot(boolean newRoot) {
    root = newRoot;
    if (root && parent) parent = null;
  }
/**
 * Returns an enumeration of the components of this vector.
 *
 * @return an enumeration of the components of this vector.
 */
 public synchronized Enumeration elements() {
   return branches.elements();
 }
/**
 * Sets the name for this capability.
 */
 public synchronized void setName(String newName) {
   name = newName;
 }
/**
 * returns the Name for this capability.
 *
 * @return the name of this capability.
 */
 public synchronized String getName() {
   return name;
 }
/**
 * Adds a new capability as a branch.
 *
 * @param newCapability the new capability to be added to the node.
 */
 public synchronized void addCapability(String newCapability) {
   Capability c = new Capability(newCapability,this);
   branches.addElement(c);
 }
/**
 * removes a capability from the branches.
 *
 * @param oldCapability the capability to be removed.
 * @return false if the object spcified did not exist. true if it did.
 */
 public synchronized boolean removeCapability(String oldCapability) {
   Enumeration e = branches.elements();
   boolean stopper = e.hasMoreElements();
   String n;
   Capability c = null;
   while (e.hasMoreElements() && stopper) {
     c = ((Capability)e.nextElement());
     n = c.getName();
     if (n.equals(oldCapability)) {
       stopper = false;
     }
   }
   if (stopper && (c != null)) {
     return branches.removeElement(c);
   } else {
     return false;
   }

 } 
/**
 * Saves this object to the specified output stream.
 *
 * @param oos the output stream for saving.
 * @exception IOException if the save fails.
 */
  void writeObject(ObjectOutputStream oos) throws IOException {
    oos.defaultWriteObject();
  }
/**
 * reads this class from the spceified input stream.
 *
 * @param ois the input stream for reading.
 * @exception ClassNotFoundException if the class cannot be found.
 * @exception IOException if some other IO excpetion occurs.
 */
  void readObject(ObjectInputStream ois) throws ClassNotFoundException, IOException {
    ois.defaultReadObject();
  }
/**
 *
 */
  public synchronized void removeGeneralEventListener(GeneralEventListener l) {
    if (generalEventListeners != null && generalEventListeners.contains(l)) {
      Vector v = (Vector) generalEventListeners.clone();
      v.removeElement(l);
      generalEventListeners = v;
    }
  }
/**
 *
 */
  public synchronized void addGeneralEventListener(GeneralEventListener l) {
    Vector v = generalEventListeners == null ? new Vector(2) : (Vector) generalEventListeners.clone();
    if (!v.contains(l)) {
      v.addElement(l);
      generalEventListeners = v;
    }
  }
/**
 *
 */
  protected void fireReceiveEvent(GeneralEvent e) {
    if (generalEventListeners != null) {
      Vector listeners = generalEventListeners;
      int count = listeners.size();
      for (int i = 0; i < count; i++)
        ((GeneralEventListener) listeners.elementAt(i)).receiveEvent(e);
    }
  }
/**
 *
 */
  public void setParent(Capability newParent) {
    if (getRoot()) {
      parent = null;
    } else {
      parent = newParent;
    }
  }
 /*
  * Returns a list of parents from the closest to the farthest.
  *
  * @return a list of parents from the closest to the farthest.
  */
  public Capability getParent() {
    return parent;
  }
/**
 *
 */
  public void setCommand(Command newCommand) {
    command = newCommand;
  }
/**
 *
 */
  public Command getCommand() throws NoCommandAssignedException{
    return command;
  }
/**
 *
 */
  public void setNounForm(String newNounForm) {
    nounForm = newNounForm;
  }
/**
 *
 */
  public String getNounForm() {
    return nounForm;
  }

}