package eu.dnetlib.apps.oai2ftp.utils;

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.UUID;

import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.lang3.StringUtils;

import eu.dnetlib.apps.oai2ftp.model.CollectionInfo;
import eu.dnetlib.apps.oai2ftp.model.CollectionLogEntry;
import eu.dnetlib.apps.oai2ftp.model.ExecutionStatus;

public class SimpleUtils {

	private static final String UTF_8 = StandardCharsets.UTF_8.toString();

	private static final DateTimeFormatter oaiDateFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");

	public static String generateNewJobId() {
		return "job-" + UUID.randomUUID();
	}

	public static String oaiFirstUrl(final String baseUrl, final String format, final String setSpec, final LocalDateTime from, final LocalDateTime until) {
		try {
			String url = baseUrl + "?verb=ListRecords&metadataPrefix=" + URLEncoder.encode(format, UTF_8);

			if (setSpec != null && !setSpec.isEmpty()) {
				url += "&set=" + URLEncoder.encode(setSpec, UTF_8);
			}
			if (from != null) {
				url += "&from=" + URLEncoder.encode(from.format(oaiDateFormatter), UTF_8);
			}
			if (until != null) {
				url += "&until=" + URLEncoder.encode(until.format(oaiDateFormatter), UTF_8);
			}
			return url;
		} catch (final UnsupportedEncodingException e) {
			throw new RuntimeException(e);
		}
	}

	public static String oaiNextUrl(final String baseUrl, final String rtoken) {
		try {
			if (StringUtils.isNotBlank(rtoken)) {
				return baseUrl + "?verb=ListRecords&resumptionToken=" + URLEncoder.encode(rtoken, UTF_8);
			} else {
				return null;
			}
		} catch (final UnsupportedEncodingException e) {
			throw new RuntimeException(e);
		}
	}

	public static CollectionInfo logToInfo(final CollectionLogEntry log) {
		final CollectionInfo info = new CollectionInfo();
		info.setId(log.getId());
		info.setOaiBaseUrl(log.getOaiBaseUrl());
		info.setOaiFormat(log.getOaiFormat());
		info.setOaiSet(log.getOaiSet());
		info.setOaiFrom(log.getOaiFrom());
		info.setOaiUntil(log.getOaiUntil());
		info.setFtpServer(log.getFtpServer());
		info.setFtpDir(log.getFtpDir());
		info.setStart(log.getStart());
		info.setEnd(log.getEnd());
		info.setExecutionStatus(log.isSuccess() ? ExecutionStatus.COMPLETED : ExecutionStatus.FAILED);
		info.setTotal(log.getTotal());
		info.setMessage(log.getMessage());
		return info;
	}

	public static CollectionLogEntry infoToLog(final CollectionInfo info) {
		final CollectionLogEntry log = new CollectionLogEntry();
		log.setId(info.getId());
		log.setOaiBaseUrl(info.getOaiBaseUrl());
		log.setOaiFormat(info.getOaiFormat());
		log.setOaiSet(info.getOaiSet());
		log.setOaiFrom(info.getOaiFrom());
		log.setOaiUntil(info.getOaiUntil());
		log.setFtpServer(info.getFtpServer());
		log.setFtpDir(info.getFtpDir());
		log.setStart(info.getStart());
		log.setEnd(info.getEnd());
		log.setSuccess(info.getExecutionStatus() == ExecutionStatus.COMPLETED);
		log.setTotal(info.getTotal());
		log.setNumberOfCalls(info.getCalls().size());
		log.setMessage(info.getMessage());
		return log;
	}

	public static String oaiIdToFilename(final String id) {
		return DigestUtils.md5Hex(id) + ".xml";
	}
}