package graph;
import graph.*;
import graph.cluster.*;
import graph.rep.*;
import java.awt.*;
import java.util.*;

/**
 * A general DFS action.
 *
 * @author Michael Shilman (michaels@eecs.berkeley.edu)
 * @version $Id$
 */
 
//XXX
abstract class FooAction {
	abstract void apply(Graph g);
}
 
public class DFSAction implements Action {
	public FooAction preInit = null;
	public FooAction postInit = null;
	public FooAction preStep = null;
	public FooAction postStep = null;
	public FooAction preFinish = null;
	public FooAction postFinish = null;
	
	//    A
	//   /|\   If m_parent is A and m_prev is B, then 
	//  B C D  step() will operate on C.
	Node m_parent;
	Node m_prev;
	
	public void apply(Graph g) {
		init(g);
		while (true /* XXX */) {
			step(g);
		}
	}
	
	public void init(Graph g) {
		if(preInit != null) { preInit.apply(g); }
		//unmark all nodes
		if(postInit != null) { postInit.apply(g); }
	}
	
	public void step(Graph g) {
		if(preStep != null) { preStep.apply(g); }
		//mark and recurse
		if(postStep != null) { postStep.apply(g); }
	}
	
	public void finish(Graph g) {
		if(preFinish != null) { preFinish.apply(g); }
		//unmark all nodes
		if(postFinish != null) { postFinish.apply(g); }
	}
}