package dk.itu.nulx30.graph;

import java.io.Serializable;

import java.util.ArrayList;
import java.util.List;

/**
 * Class <code>Vertex</code> is the representation of a vertex
 * in the <code>Graph</code>. The class contains information
 * about the location of the <code>Vertex</code> and a
 * <code>List</code> of all outgoing <code>Edges</code>.
 *
 * @author  Mikkel Bundgaard
 * @author  Troels C. Damgaard
 * @author  Federico Decara
 * @author  Jacob W. Winther
 */
public class Vertex implements Comparable, Serializable, Cloneable {
  /** A <code>List</code> containing the outgoing Edges of the object */
  private List adj;
  /** The index of the object */
  private int myIndex;
  /** The position of the object */
  private double xPos, yPos;

  /**
   * Class constructor specifying the index of the object.
   *
   * @param index The index of the vertex.
   */
  public Vertex ( int index ) {
    adj = new ArrayList();
    myIndex = index;
  }

  /**
   * Class constructor specifying the index and the position 
   * of the object.
   *
   * @param index The index of the object.
   * @param x     The horizontal position of the object.
   * @param y     The vertical position of the object.
   */
  public Vertex ( int index, int x, int y ) {
    this( index );
    xPos = x;
    yPos = y;
  }

  /**
   * Returns a <code>List</code> containing all the 
   * outgoing <code>Edges</code> from the object.
   *
   * @return  a <code>List</code> containing all the 
   * outgoing <code>Edges</code>.
   */
  public List getEdges() {
    return adj;
  }
  
  /**
   * Provides a string representation of the index of the object.
   *
   * @return a string representation of this vertex.
   */
  public String toString() {
    return Integer.toString( myIndex );  
  }
  
  /**
   * This method is called on every ant arrival to this vertex.
   * NOTE : Currently this method does nothing!.
   */    
  public void antArrival(){ }
  
  /**
   * Compares this vertex to another <code>Object</code>.
   * If the <code>Object</code> is not a <code>Vertex</code>, this function 
   * throws a ClassCastException otherwise.
   *
   * @param  other  The <code>Object</code> to compare to.
   *
   * @return  the value 0 if the argument object is equal to this object;
   * -1 if this object has an index smaller than the index of the argument;
   * 1 if this object has an index larger than the index of the argument.
   *
   */
  public int compareTo( Object other ) {
    Vertex otherV = ( Vertex ) other;
    return ( myIndex < otherV.myIndex ) ? -1 :
           ( myIndex == otherV.myIndex ? 0 : 1 );
  }
  
  /**
   * Compares this <code>Vertex</code> to the specified object. 
   * The result is true if and only if the argument is not null,
   * is a <code>Vertex</code> and has the same index as this 
   * <code>Vertex</code>.
   *
   * @param  other  The <code>Object</code> to compare to.
   *
   * @return a boolean which is true if and only if this object is equal 
   * to the argument, otherwise false.
   */
  public boolean equals( Object other ) {
    return myIndex == ( ( Vertex ) other ).myIndex;
  }

  /**
   * Returns the index of the <code>Vertex</code>.
   *
   * @return the index of the <code>Vertex</code>.
   */
  public int getIndex() {
    return myIndex;
  }

  /**
   * Returns the horizontal position of the object.
   *
   * @return horizontal position of the object.
   */
  public double getXPos() {
    return xPos;
  }

  /**
   * Returns the vertical position of the object.
   *
   * @return vertical position of the object.
   */
  public double getYPos() {
    return yPos;
  }

  /**
   * Sets the horizontal position of the object to the new value.
   *
   * @param newXpos the new horizontal position of the object.
   */
  public void setXPos( double newXpos  ) {
    xPos = newXpos;
  }

  /**
   * Sets the vertical position of the object to the new value.
   *
   * @param newYpos the new vertical position of the object.
   */
  public void setYPos( double newYpos  ) {
    yPos = newYpos;
  }
}