package org.gcube.data.access.storagehub.handlers.vres;

import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;

import javax.jcr.Repository;
import javax.jcr.SimpleCredentials;

import org.gcube.common.storagehub.model.exceptions.BackendGenericError;
import org.gcube.common.storagehub.model.items.Item;
import org.gcube.data.access.storagehub.handlers.items.Node2ItemConverter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class VRE {

	private static final Logger logger = LoggerFactory.getLogger(VRE.class);

	private Item vreFolder;
	private Future<List<Item>> result;
	private VREQueryRetriever vreQueryRetriever;
	private ExecutorService executor;

	protected VRE(Item item, Repository repository, SimpleCredentials credentials, Node2ItemConverter node2Item, ExecutorService executor) {
		super();
		this.vreFolder = item;
		this.executor = executor;
		vreQueryRetriever = new VREQueryRetriever(repository, credentials, node2Item, vreFolder);
		result = executor.submit(vreQueryRetriever);
	}

	public Item getVreFolder() {
		return vreFolder;
	}

	public synchronized List<Item> getRecents() throws BackendGenericError{
		try {
			logger.trace("getting recents");
			if (result.isDone()) {
				result = executor.submit(vreQueryRetriever);
			}
			return result.get();
		}catch(Exception ee) {
			throw new BackendGenericError(ee);
		}
	}



}