//////////////////////////////////////////////////////////////////////
// Node.java                                                        //
// --Container for Node IP and structure information--              //
//                                                                  //
// Supervised Peer-to-peer Overlay Network (SPON) Simulator         //
//                                                                  //
//                                                                  //
// Computer Science M.S.E. Project                                  //
// Programmed by: Joey Chau                                         //
// Copyright: February, 2003                                        //
//                                                                  //
// Research Advisor: Christian Scheideler                           //
//                   Computer Science                               //
//                   Johns Hopkins University                       //
//////////////////////////////////////////////////////////////////////
import java.io.*;
import java.net.*;
import java.util.*;

/** 
    Node used to hold and manage parent, child, and next node information
*/
class Node 
{
  private String mKey;
  private int mHeight;
  private String mLeftChild;
  private String mRightChild;
  private String mNext;
  
  /** 
      Default node constructor
  */
  public Node() {
    mKey = " ";
    mHeight = -1;
    mLeftChild = " ";
    mRightChild = " ";
    mNext = " ";
  }
  
  /**
     Node constructor which declares the source node IP
     @param iaddy - String representation of the source node IP
  */
  public Node( String iaddy ) {
    mKey = iaddy;
    mHeight = -1;
    mLeftChild = " ";
    mRightChild = " ";
    mNext = " ";
  }
  
  /**
     Copy constructor which duplicates the values of another node
     @param other - Node which will be duplicated
  */
  public Node( Node other ) {
    mKey = other.mKey;
    mHeight = other.mHeight;
    mLeftChild = other.mLeftChild;
    mRightChild = other.mRightChild;
    mNext = other.mNext;
    
  }   
  
  /**
     Modify the default key of this node
     @param iaddy - String key
  */
  public void setKey( String iaddy ) {
    mKey = iaddy;
  }
  
  /**
     Access the the key of the node
     @return String - the key
  */
  public String getKey() {
    return mKey;
  }
  
  /**
     Modify the height of this node
     @param h - int height
  */
  public void setHeight( int h ) {
    mHeight = h;
  }
  
  /**
     Access the height of this node
     @return int - height
  */
  public int getHeight() {
    return mHeight;
  }
  
  /**
     Access the right child of this node
     @return String - the key of the right child
  */
  public String getRightChild() {
    return mRightChild;
  }
  
  /**
     Modify the right child of this node
     @param rc - String key of the new right child
  */
  public void setRightChild( String rc ) {
    mRightChild = rc;
  }
  
  /**
     Access the left child of this node
     @return String - the key of the left child
  */
  public String getLeftChild() {
    return mLeftChild;
  }
  
  /**
     Modify the left child of this node
     @param lc - String key of the new left child
  */
  public void setLeftChild( String lc ) {
    mLeftChild = lc;
  }
  
  /**
     Access the next node
     @return String - the key of the next node
  */
  public String getNext() {
    return mNext;
  }
  
  /**
     Modify the next node
     @param nx - String key of the next node
  */
  public void setNext( String nx ) {
    mNext = nx;
  }
  
  /**
     Determines whether the node has not been set
     @return boolean - true if node is empty or undelcared or unset
  */
  public boolean isEmpty() {
    return (mHeight == -1);
  }
  
  /**
     String representation of the node used for communication and information maintenance
     @return String - the String representation of the information in Node
  */
  public String toString() {
    return  mKey + ":" +
      mHeight + ":" +
      mLeftChild + ":" +
      mRightChild + ":" +
      mNext;
  }
  
  /**
     Given a formated Node string, it attempts to parse the String and set the attributes of the node
     @param pStr - String containing Node information
     @boolean - true if parse was successful for the given parameter
  */
  public boolean parseString( String pStr ) {
    StringTokenizer stok = new StringTokenizer( pStr, ":" );
    int count;
    
    count = stok.countTokens();
    if( count != 5 ) {
      return false;
    }
    
    mKey = stok.nextToken();
    try {
      mHeight = Integer.parseInt( stok.nextToken() );
    }
    catch( NumberFormatException e ) {
      return false;
    }
    mLeftChild = stok.nextToken();
    mRightChild = stok.nextToken();
    mNext = stok.nextToken();
    return true;
  }
}