/*******************************************************************************
 * Copyright 2017 Graz University of Technology
 * EAAF-Core Components has been developed in a cooperation between EGIZ,  
 * A-SIT+, A-SIT, and Graz University of Technology.
 *
 * Licensed under the EUPL, Version 1.2 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * https://joinup.ec.europa.eu/news/understanding-eupl-v12
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 *******************************************************************************/
/*******************************************************************************
 *******************************************************************************/
/*******************************************************************************
 *******************************************************************************/
package at.gv.egiz.eaaf.core.impl.idp.controller;

import java.io.IOException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.text.StringEscapeUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;

import at.gv.egiz.eaaf.core.api.IRequest;
import at.gv.egiz.eaaf.core.api.IStatusMessenger;
import at.gv.egiz.eaaf.core.api.data.EAAFConstants;
import at.gv.egiz.eaaf.core.api.idp.process.ProcessEngine;
import at.gv.egiz.eaaf.core.exceptions.EAAFException;
import at.gv.egiz.eaaf.core.exceptions.EAAFIllegalStateException;
import at.gv.egiz.eaaf.core.impl.utils.TransactionIDUtils;

/**
 * Servlet that resumes a suspended process (in case of asynchronous tasks).
 * 
 * @author tknall
 * 
 */
public abstract class AbstractProcessEngineSignalController extends AbstractController {
	private static final Logger log = LoggerFactory.getLogger(AbstractProcessEngineSignalController.class);	
	
	@Autowired protected ProcessEngine processEngine;
	
	protected void signalProcessManagement(HttpServletRequest req, HttpServletResponse resp) throws IOException {
		String pendingRequestID = StringEscapeUtils.escapeHtml4(getPendingRequestId(req));
		IRequest pendingReq = null;
		try {	
			if (pendingRequestID == null) {
				new EAAFException(
						IStatusMessenger.CODES_INTERNAL_ERROR_AUTH_NOPENDIGREQID, 
						null);
				
			}
			
			pendingReq = requestStorage.getPendingRequest(pendingRequestID);
			if (pendingReq == null) {
				log.info("No PendingRequest with Id: " + pendingRequestID + " Maybe, a transaction timeout occure.");
				throw new EAAFException(IStatusMessenger.CODES_INTERNAL_ERROR_AUTH_TIMEOUT, new Object[]{pendingRequestID});
				
			}
			
			//change pending-request ID
			requestStorage.changePendingRequestID(pendingReq);
			pendingRequestID = pendingReq.getPendingRequestId();
						
			// process instance is mandatory
			if (pendingReq.getProcessInstanceId() == null) {
				throw new EAAFIllegalStateException(new Object[]{"MOA session does not provide process instance id."});
				
			}

			// wake up next task
			processEngine.signal(pendingReq);
			
		} catch (Exception ex) {		
			handleError(null, ex, req, resp, pendingReq);
			
		} finally {
			//MOASessionDBUtils.closeSession();
			TransactionIDUtils.removeAllLoggingVariables();
			
		}
		
		
	}
	
	/**
	 * Retrieves the current pending-request id from the HttpServletRequest parameter
	 * 
	 * <p/>
	 * Note that this class/method can be overwritten by modules providing their own strategy of retrieving the
	 * respective pending-request id.
	 * 
	 * @param request
	 *            The unterlying HttpServletRequest.
	 * @return The current pending-request id.
	 */
	public String getPendingRequestId(HttpServletRequest request) {
		return StringEscapeUtils.escapeHtml4(request.getParameter(EAAFConstants.PARAM_HTTP_TARGET_PENDINGREQUESTID));
		
	}

}