package org.simantics.interop.test;

import org.simantics.databoard.Bindings;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.exception.DatabaseException;
import org.simantics.layer0.Layer0;

/**
 * Object comparator that uses type and name of objects to check if objects are comparable.
 * If objects have no name, compare returns unreliable as result.
 *  
 * 
 * Difference value is amount of properties that have different values.
 * 
 * @author Marko Luukkainen <marko.luukkainen@vtt.fi>
 *
 */
public class NameComparator extends TypeComparator {
	
	@Override
	public int compare(ReadGraph g, Resource o1, Resource o2)
			throws DatabaseException {
		if (!compareType(g,o1, o2)) {
			return NO_MATCH;
		}
		if (hasName(g, o1, o2)) {
			if(!compareName(g, o1, o2))
				return NO_MATCH;
			return propsDiffCount(g,o1, o2);
		}
		return UNDECISIVE;
		
	}
	
	protected boolean compareName(ReadGraph g, Resource o1, Resource o2) throws DatabaseException {
		Layer0 l0 = Layer0.getInstance(g);
		String n1 = g.getPossibleRelatedValue(o1, l0.HasName, Bindings.STRING);
		String n2 = g.getPossibleRelatedValue(o2, l0.HasName, Bindings.STRING);
		if (n1 != null && n2 != null)
			return n1.equals(n2);
		if (n1 == null && n2 == null)
			return true;
		return false;
			
	}
	
	protected boolean hasName(ReadGraph g, Resource o1, Resource o2) throws DatabaseException {
		Layer0 l0 = Layer0.getInstance(g);
		String n1 = g.getPossibleRelatedValue(o1, l0.HasName, Bindings.STRING);
		String n2 = g.getPossibleRelatedValue(o2, l0.HasName, Bindings.STRING);
		if (n1 != null && n2 != null)
			return true;
		return false;
			
	}

}