/*******************************************************************************
 *******************************************************************************/
package at.gv.egiz.eidas.specific.modules.authmodule_eIDASv2;

import java.io.IOException;

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

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.google.common.collect.ImmutableSortedSet;

import at.gv.egiz.eaaf.core.impl.idp.controller.AbstractProcessEngineSignalController;
import at.gv.egiz.eidas.specific.modules.authmodule_eIDASv2.exception.eIDASAuthenticationException;
import at.gv.egiz.eidas.specific.modules.authmodule_eIDASv2.service.eIDASAttributeRegistry;
import eu.eidas.auth.commons.EidasParameterKeys;
import eu.eidas.auth.commons.light.ILightResponse;
import eu.eidas.specificcommunication.SpecificCommunicationDefinitionBeanNames;
import eu.eidas.specificcommunication.exception.SpecificCommunicationException;
import eu.eidas.specificcommunication.protocol.impl.SpecificConnectorCommunicationServiceImpl;


/**
 * @author tlenz
 *
 */
@Controller
public class eIDASSignalServlet extends AbstractProcessEngineSignalController {
	
	private static final Logger log = LoggerFactory.getLogger(eIDASSignalServlet.class);
	@Autowired private ApplicationContext context;
	@Autowired private eIDASAttributeRegistry attrRegistry;
	
	public eIDASSignalServlet() { 
		super();
		log.debug("Registering servlet " + getClass().getName() + 
				" with mappings '"+ Constants.eIDAS_HTTP_ENDPOINT_SP_POST + 
				"' and '"+ Constants.eIDAS_HTTP_ENDPOINT_SP_REDIRECT + "'.");
		
	}
	
	@RequestMapping(value = { Constants.eIDAS_HTTP_ENDPOINT_SP_POST, 
							  Constants.eIDAS_HTTP_ENDPOINT_SP_REDIRECT
							}, 
					method = {RequestMethod.POST, RequestMethod.GET})
	public void restoreEidasAuthProcess(HttpServletRequest req, HttpServletResponse resp) throws IOException {
		signalProcessManagement(req, resp);
	}
	
	
	/**
	 * Protocol specific implementation to get the pending-requestID 
	 * from http request object
	 * 
	 * @param request The http Servlet-Request object
	 * @return The Pending-request id 
	 * 
	 */
	@Override
	public String getPendingRequestId(HttpServletRequest request) {
		//String sessionId = super.getPendingRequestId(request);
		
		try {
			//get token from Request
			final String tokenBase64 = request.getParameter(EidasParameterKeys.TOKEN.toString());			
			if (StringUtils.isEmpty(tokenBase64)) {
				log.warn("NO eIDAS message token found.");
				throw new eIDASAuthenticationException("eidas.04", null);
				
			}
			log.trace("Receive eIDAS-node token: " + tokenBase64 + " Starting transaction-restore process ... ");
			
			
			
			final SpecificConnectorCommunicationServiceImpl specificConnectorCommunicationService =
	                (SpecificConnectorCommunicationServiceImpl) context.getBean(SpecificCommunicationDefinitionBeanNames.SPECIFIC_CONNECTOR_COMMUNICATION_SERVICE.toString());
			ILightResponse eIDASResponse = specificConnectorCommunicationService.getAndRemoveResponse(tokenBase64, 
    			ImmutableSortedSet.copyOf(attrRegistry.getCoreAttributeRegistry().getAttributes()));
				
			String pendingReqId = null;
			if (StringUtils.isEmpty(eIDASResponse.getRelayState())) {
				log.debug("eIDAS Node returns no RelayState. ");
				
				if (authConfig.getBasicMOAIDConfigurationBoolean(
						Constants.CONIG_PROPS_EIDAS_NODE_WORKAROUND_USEREQUESTIDASTRANSACTIONIDENTIFIER, 
						false)) {
					log.trace("Use lightRequestId to recover session ... ");
					pendingReqId = transactionStorage.get(eIDASResponse.getInResponseToId(), String.class);
					if (StringUtils.isNotEmpty(pendingReqId)) {
						log.debug("Restoring session with lightRequestId ... ");
						transactionStorage.remove(eIDASResponse.getInResponseToId());
						
					}		
				} 
											
			} else {			
				log.debug("Find transaction identifier in SAML2 'RelayState': " + eIDASResponse.getRelayState());
				pendingReqId = eIDASResponse.getRelayState();
				 				
			}

			if (StringUtils.isNotEmpty(pendingReqId)) {
				request.setAttribute(Constants.DATA_FULL_EIDAS_RESPONSE, eIDASResponse);
				return pendingReqId;
				
			}

			log.info("NO transaction identifier found! Stopping process ....");
			log.trace("FullResponse: " + eIDASResponse.toString());
			
		} catch (SpecificCommunicationException e) {
			log.warn("Can NOT load eIDAS Response from cache.", e);
			log.debug("eIDAS response token was: " + request.getParameter(EidasParameterKeys.TOKEN.toString()));
			
		} catch (Exception e) {
			log.warn("Unable to retrieve moa session id.", e);
			
		}

		return null;
	}
	
}