package graph.test;
import graph.*;
import java.util.*;

/**
 * A random initialization for a graph.  Creates a specified
 * number of nodes and subgraphs and attaches them together
 * randomly.  Does not lay them out in any way.
 *
 * @author Michael Shilman (michaels@eecs.berkeley.edu)
 * @version $Id$
 */
public class RandomInit implements Action {
	boolean m_recurse = false;//XXX
	int m_numNodes = 30;
	int m_numGraphs = 20;
	int m_numEdges = 3;
	static Random s_rand = new Random(System.currentTimeMillis());
	
	/**
     * Create a new RandomInit actin which adds a reasonable
     * number of nodes, graphs, and edges.
     */  
    public RandomInit() {
    }
    
    /**
     * Create a new RandomInit actin which adds the specified
     * number of nodes and graphs.
     *
     * @param numNodes		The number of nodes to be added
     * @param numGraphs		The number of subgraphs to be added
     * @param numEdges		The number of edges to be added per node/subgraph
     */  
    public RandomInit(int numNodes, int numGraphs, int m_numEdges) {
    	m_numNodes = numNodes;
    	m_numGraphs = numGraphs;
    }
    
	
	public void apply(Graph g) {
		step(g);
	}
	
	public void init(Graph g) {
		
	}
	
	public void step(Graph g) {
        Node n;
        for(int i = 0; i < m_numNodes; i++) {
        	n = new Node();
        	n.name = new String("Node " + i);
        	n.lbl.label = n.name;
        	g.add(n);
        }
        
        Graph sub;
        for(int i = 0; i < m_numGraphs; i++) {
        	sub = new Graph();
        	sub.name = new String("Graph " + i);
        	sub.lbl.label = sub.name;
        	g.add(sub);
        }
      
        
        for(Enumeration e = g.nodes.elements(); e.hasMoreElements(); ) {
            n = (Node)e.nextElement();
            while(n.out.size() < m_numEdges) {
                int rand = (int)(s_rand.nextFloat() * g.nodes.size());
                Node n2 = (Node)g.nodes.elementAt(rand);
                if(!n2.equals(n)) {
                	try {
                    	n.attach(n2);
                    }
                    catch(Exception ex) {
                    	System.out.println(ex);
                    	System.exit(0);
                    }
                }
            }
        }
    }	
    
	public void finish(Graph g) {
		
	}
}