package causation.lab;

import java.util.*;

import causation.lab.WBVariable;

/**
 * This class encodes the state attributes of the WBVariables in a 
 * CausalityLab that are relevant to an experiment.  Specifically, for
 * every variable, it encodes whether that variable is on the workbench,
 * and whether it is randomized, locked (and the value, if it is), or 
 * not manipulated.
 *
 * @see	Workbench
 * @see	WBVariable
 * @version	1.0	Aug 30, 1999
 * @author	David Danks
 */
 
public class ExperimentalSetup {

/////////////////// Static Class Variables ///////////////////
	public static final String RANDOMIZED = "*****RANDOMIZED*****";
	public static final String NOT_ON_BENCH = "*****NOTONBENCH*****";
	public static final String NO_MANIP = "*****NO MANIPULATION*****";

/////////////////// Instance Variables ///////////////////
	private Hashtable states;

/////////////////// Constructors ///////////////////
/**
 * Constructs an ExperimentalSetup object for the experimental setup 
 * currently on the given Workbench.
 * @param	wb	The Workbench whose experimental setup is being encoded
 */	
	public ExperimentalSetup(Workbench wb) {
		WBVariable[] vars = wb.getVariables();
		states = new Hashtable();
		
		String[] onWorkbench = wb.getOnWorkbenchVariableNames();
		
		for (int i=0; i<vars.length; i++) { 
			String state = NOT_ON_BENCH;
			// check if it's on the workbench
			int j; for (j=0; j<onWorkbench.length; j++) {
				if (onWorkbench[j].equals(vars[i].getName())) {
					// so, change the value of state
					if (vars[i].isLocked()) 
						state = vars[i].getActiveValue();
					else if (vars[i].isRandomized())
						state = ExperimentalSetup.RANDOMIZED;
					else state = ExperimentalSetup.NO_MANIP;
					break;
				}
			}
			states.put(vars[i].getName(), state);
		}
	}

/////////////////// Instance Methods ///////////////////
/**
 * @return	A Hashtable with key=variable name, and value=the state (as
 * 			a String)
 */
	public Hashtable getStates() { return states; }

/**
 * @param	exp	The ExperimentalSetup to test
 * @return	<code>true</code>, if the variable names are the same, and
 *				the state of the variable in each ExperimentalSetup is the
 *				same;
 *				<code>false</code>, otherwise.
 */
	public boolean isEquivalentTo(ExperimentalSetup exp) {
		Hashtable expSt = exp.getStates();
		if (expSt.size() != states.size()) return false;
		
		Enumeration keys = states.keys();
		while (keys.hasMoreElements()) {
			String key = (String)keys.nextElement();
			String value = (String)states.get(key);
			String eValue = (String)expSt.get(key);
			if (value == null) {
				if (eValue != null) return false;
			}
			else if (!(value.equals(eValue))) return false;
		}
		
		return true;
	}
	
}