/**
 * Container for link between two Osm nodes (pre-pocessor version)
 *
 * @author ab
 */
package btools.mapcreator;


public class OsmLinkP
{
 /**
   * The description bitmap is mainly the way description
   * used to calculate the costfactor
   */
  public byte[] descriptionBitmap;

 /**
   * The target is either the next link or the target node
   */
  protected OsmNodeP sourceNode;
  protected OsmNodeP targetNode;

  protected OsmLinkP previous;
  protected OsmLinkP next;

  
  public OsmLinkP( OsmNodeP source, OsmNodeP target )
  {
    sourceNode = source;
    targetNode = target;
  }
  
  protected OsmLinkP()
  {
  }

  public final boolean counterLinkWritten( )
  {
	  return descriptionBitmap == null;
  }

  /**
   * Set the relevant next-pointer for the given source
   */
  public void setNext( OsmLinkP link, OsmNodeP source )
  {
	 if ( sourceNode == source )
     {
       next = link;
     }
     else if ( targetNode == source )
     {
       previous = link;
     }
     else
     {
       throw new IllegalArgumentException( "internal error: setNext: unknown source" );
     }
  }  
  
  /**
   * Get the relevant next-pointer for the given source
   */
  public OsmLinkP getNext( OsmNodeP source )
  {
    if ( sourceNode == source )
    {
      return next;
    }
    else if ( targetNode == source )
	{
      return previous;
    }
    else
    {
      throw new IllegalArgumentException( "internal error: gextNext: unknown source" );
    }
  }

  /**
   * Get the relevant target-node for the given source
   */
  public OsmNodeP getTarget( OsmNodeP source )
  {
    if ( sourceNode == source )
    {
      return targetNode;
    }
    else if ( targetNode == source )
	{
      return sourceNode;
    }
    else
    {
      throw new IllegalArgumentException( "internal error: getTarget: unknown source" );
    }
  }

  /**
   * Check if reverse link for the given source
   */
  public boolean isReverse( OsmNodeP source )
  {
    if ( sourceNode == source )
    {
      return false;
    }
    else if ( targetNode == source )
	{
      return true;
    }
    else
    {
      throw new IllegalArgumentException( "internal error: isReverse: unknown source" );
    }
  }

}