/**
 * The contents of this file are subject to the license and copyright
 * detailed in the LICENSE and NOTICE files at the root of the source
 * tree and available online at
 *
 * http://www.dspace.org/license/
 */

package org.dspace.rdf.storage;

import java.sql.SQLException;
import java.util.List;
import java.util.UUID;

import org.apache.logging.log4j.Logger;
import org.dspace.content.DSpaceObject;
import org.dspace.content.factory.ContentServiceFactory;
import org.dspace.core.Constants;
import org.dspace.core.Context;
import org.dspace.identifier.IdentifierException;
import org.dspace.identifier.service.DOIService;
import org.springframework.beans.factory.annotation.Autowired;

/**
 * @author pbecker
 */
public class DOIURIGenerator implements URIGenerator {
    private static final Logger log = org.apache.logging.log4j.LogManager.getLogger(DOIURIGenerator.class);

    protected static URIGenerator fallback;

    @Autowired(required = true)
    public static void setFallback(URIGenerator fallback) {
        DOIURIGenerator.fallback = fallback;
    }

    @Autowired(required = true)
    protected DOIService doiService;

    @Override
    public String generateIdentifier(Context context, int type, UUID id, String handle, List<String> identifiers)
        throws SQLException {
        if (type != Constants.SITE
            && type != Constants.COMMUNITY
            && type != Constants.COLLECTION
            && type != Constants.ITEM) {
            return null;
        }

        String doi = null;
        for (String identifier : identifiers) {
            try {
                doi = doiService.DOIToExternalForm(identifier);
            } catch (IdentifierException ex) {
                // identifier is not a DOI: no problem, keep on looking.
            }
        }
        if (doi != null) {
            return doi;
        } else {
            log.info("Didn't find a DOI for " + Constants.typeText[type] + ", id " + id.toString()
                         + ", will use fallback URIGenerator.");
            return fallback.generateIdentifier(context, type, id, handle, identifiers);
        }
    }

    @Override
    public String generateIdentifier(Context context, DSpaceObject dso)
        throws SQLException {
        return generateIdentifier(
            context,
            dso.getType(),
            dso.getID(),
            dso.getHandle(),
            ContentServiceFactory.getInstance().getDSpaceObjectService(dso)
                                 .getIdentifiers(context, dso)
        );
    }

}
