package org.simantics.district.network.techtype.requests;

import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.common.request.ResourceRead;
import org.simantics.db.exception.DatabaseException;
import org.simantics.district.network.ontology.DistrictNetworkResource;
import org.simantics.layer0.Layer0;

public class PossibleTechTypeKeyName extends ResourceRead<String> {
	public PossibleTechTypeKeyName(Resource componentType) {
		super(componentType);
	}

	@Override
	public String perform(ReadGraph graph) throws DatabaseException {
		Layer0 L0 = Layer0.getInstance(graph);
		DistrictNetworkResource DN = DistrictNetworkResource.getInstance(graph);
		
		for (Resource r : graph.getObjects(resource, L0.DomainOf)) {
			Resource accessor = graph.getPossibleObject(r, L0.valueAccessor);
			if (accessor.equals(DN.TechType_Functions_techTypeCodeValueAccessor)) {
				return graph.getRelatedValue2(r, L0.HasName);
			}
		}
		
		return null;
	}
}