// Medusa is a graph viewer which allows interactive editing of networks
// (edges and nodes) and also connects to databases.
//
// Copyright (C) 2006 Sean Hooper
//
// 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., 
// 59 Temple Place, Suite 330, 
// Boston, MA 02111-1307 USA

/*
 * BasicEdge.java
 *
 * Created on den 9 februari 2005, 23:20
 */

package medusa.graph;

import java.io.Serializable;

/**
 * Basic representation of an Edge as a connection between two 
 * nodes. Note that a node will only exist if there is an edge between
 * them. This Graph representation is not based on nodes but edges.
 * @author unto
 */
public abstract class BasicEdge implements Serializable{
    
    /**
     * Node 1
     */
    public String n1;
    /**
     * Node 2
     */
    public String n2;
    
    /**
     * Name of the first node
     * @return String name
     */
    public String getFromName(){
	return n1;
    }
    /**
     * Name of the second node
     * @return String name
     */
    public String getToName(){
	return n2;
    }
    /**
     * Quick report of the two nodes
     * @return String
     */
    public String report(){
	return n1+"\t"+n2;
    }
    /**
     * Check if two edges have the same nodes
     * @param o Object representation of BasicEdge
     * @return True if same nodes occur in the two edges
     */
    public boolean sameName(Object o){
	
	BasicEdge be = (BasicEdge) o;	
	    
	int c12 = n1.compareTo(be.n2);
	int c21 = n2.compareTo(be.n1);
	int c11 = n1.compareTo(be.n1);
	int c22 = n2.compareTo(be.n2);
	
	if ((c12==0)&(c21==0))
	    return true;
	if ((c11==0)&(c22==0))
	    return true;
	return false;
    }
    
    /**
     * Checks if Node n is in the edge
     * @param lbl label of node
     * @return True if edge contains the label
     */
    public boolean contains(String lbl){
	return ((n1.compareTo(lbl)==0) |
		(n2.compareTo(lbl)==0) );
    }

    /**
     * Check if edge if opposite to another edge, i.e if
     * edge a contains nodes (n1,n2) and edge b 
     * contains (n2,n1)/
     * @param o BasicEdge cast as Object
     * @return True if oppposites
     */
    public boolean oppositeName(Object o){
	BasicEdge be = (BasicEdge) o;	
	    
	int c12 = n1.compareTo(be.n2);
	int c21 = n2.compareTo(be.n1);
		
	if ((c12==0)&(c21==0))
	    return true;
	return false;
    }
    /**
     * Node 1
     * @return 
     */
    public String[] getNodes(){
	String[] result = new String[2];
	result[0]=n1;
	result[1]=n2;
	return result;
    }
}