/*
 * This is eMonocot, a global online biodiversity information resource.
 *
 * Copyright © 2011–2015 The Board of Trustees of the Royal Botanic Gardens, Kew and The University of Oxford
 *
 * eMonocot is free software: you can redistribute it and/or modify it under the terms of the
 * GNU Affero General Public License as published by the Free Software Foundation, either version 3
 * of the License, or (at your option) any later version.
 *
 * eMonocot is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * The complete text of the GNU Affero General Public License is in the source repository as the file
 * ‘COPYING’.  It is also available from <http://www.gnu.org/licenses/>.
 */
package org.emonocot.job.gbif;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.batch.core.ExitStatus;
import org.springframework.batch.core.StepExecution;
import org.springframework.batch.core.StepExecutionListener;
import org.springframework.batch.item.ParseException;
import org.springframework.batch.item.UnexpectedInputException;
import org.springframework.batch.item.xml.StaxEventItemReader;
import org.springframework.core.io.FileSystemResource;
import org.springframework.oxm.Unmarshaller;

public class HasMoreRecords implements StepExecutionListener {

	private Logger logger = LoggerFactory.getLogger(HasMoreRecords.class);

	private StepExecution stepExecution;

	private Unmarshaller unmarshaller;

	public void setUnmarshaller(Unmarshaller unmarshaller) {
		this.unmarshaller = unmarshaller;
	}

	public ExitStatus execute(String temporaryFileName) throws Exception {
		try {
			StaxEventItemReader<GbifResponse> staxEventItemReader = new StaxEventItemReader<GbifResponse>();
			staxEventItemReader.setFragmentRootElementName(
					"{http://portal.gbif.org/ws/response/gbif}gbifResponse");
			staxEventItemReader.setUnmarshaller(unmarshaller);
			staxEventItemReader.setResource(new FileSystemResource(
					temporaryFileName));

			staxEventItemReader.afterPropertiesSet();
			staxEventItemReader.open(stepExecution.getExecutionContext());

			GbifResponse gbifResponse = staxEventItemReader.read();
			staxEventItemReader.close();
			if(gbifResponse.getExceptionReport() != null) {
				return new ExitStatus("SERVER_ERROR").addExitDescription(gbifResponse.getExceptionReport());
			} else if (gbifResponse.getHeader() == null || gbifResponse.getHeader().getSummary() == null) {
				logger.info("Header Not Found");
				return new ExitStatus("NO_MORE_RECORDS");
			} else {
				if(gbifResponse.getHeader().getSummary().getNext() != null){
					stepExecution.getJobExecution().getExecutionContext().remove("startindex");
					stepExecution.getJobExecution().getExecutionContext().put("startindex", gbifResponse.getHeader().getSummary().getNext());
					return new ExitStatus("HAS_MORE_RECORDS");
				} else {
					return new ExitStatus("NO_MORE_RECORDS");
				}
			}
		} catch (UnexpectedInputException e) {
			logger.error(e.getMessage());
			for (StackTraceElement ste : e.getStackTrace()) {
				logger.error(ste.toString());
			}
			return ExitStatus.FAILED;
		} catch (ParseException e) {
			logger.error(e.getMessage());
			for (StackTraceElement ste : e.getStackTrace()) {
				logger.error(ste.toString());
			}
			return ExitStatus.FAILED;
		} catch (Exception e) {
			logger.error(e.getMessage());
			for (StackTraceElement ste : e.getStackTrace()) {
				logger.error(ste.toString());
			}
			return ExitStatus.FAILED;
		}
	}

	public ExitStatus afterStep(StepExecution stepExecution) {
		return null;
	}

	public void beforeStep(StepExecution stepExecution) {
		this.stepExecution = stepExecution;
	}

}