package org.simantics.db.layer0.variable;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import org.simantics.db.ReadGraph;
import org.simantics.db.exception.DatabaseException;

abstract public class VariableMapImpl implements VariableMap {

	@Override
	public Variable getVariable(ReadGraph graph, Variable context, String name) throws DatabaseException {
		return getVariables(graph, context, null).get(name);
	}

	@Override
	public Map<String, Variable> getVariables(ReadGraph graph, Variable context, String classification, Map<String, Variable> map) throws DatabaseException {
		
    	Map<String,Variable> all = getVariables(graph, context, null);
    	if(all.isEmpty()) return all;
    	
    	for(Map.Entry<String, Variable> entry : all.entrySet()) {
    		Set<String> classifications = entry.getValue().getClassifications(graph);
    		if(classifications.contains(classification)) {
    			if(map == null) map = new HashMap<String,Variable>();
    			map.put(entry.getKey(), entry.getValue());
    		}
    	}
    	
    	return map;
		
	}

}