package org.gcube.informationsystem.utils.documentation.knowledge;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.gcube.informationsystem.types.reference.properties.LinkedEntity;

public class Knowledge {
	
	private static Knowledge singleton;
	
	public static Knowledge getInstace() {
		if(Knowledge.singleton==null) {
			Knowledge.singleton = new Knowledge();
		}
		return Knowledge.singleton;
	}
	
	protected Map<String, List<LinkedEntity>> map;
	
	private Knowledge(){
		this.map = new LinkedHashMap<>();
	}
	
	protected void add(String typeName, LinkedEntity linkedEntity) {
		List<LinkedEntity> list = map.get(typeName);
		if(list==null) {
			list = new ArrayList<>();
			map.put(typeName, list);
		}
		list.add(linkedEntity);
	}
	
	public void add(LinkedEntity linkedEntity) {
		String source = linkedEntity.getSource();
		add(source, linkedEntity);
		String relation = linkedEntity.getRelation();
		add(relation, linkedEntity);
		String target = linkedEntity.getTarget();
		add(target, linkedEntity);
	}
	
	public void addAll(List<LinkedEntity> linkedEntities) {
		for(LinkedEntity le : linkedEntities) {
			add(le);
		}
	}
	
	public List<LinkedEntity> getUsage(String typeName){
		List<LinkedEntity> list = map.get(typeName);
		return list;
	}
	
}