package at.gv.egovernment.moa.id.auth.modules.eidas.tasks;

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

import org.opensaml.saml2.core.StatusCode;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import at.gv.egiz.eaaf.core.api.idp.process.ExecutionContext;
import at.gv.egiz.eaaf.core.exceptions.TaskExecutionException;
import at.gv.egiz.eaaf.core.impl.idp.auth.modules.AbstractAuthServletTask;
import at.gv.egovernment.moa.id.advancedlogging.MOAIDEventConstants;
import at.gv.egovernment.moa.id.auth.data.AuthenticationSessionStorageConstants;
import at.gv.egovernment.moa.id.auth.data.AuthenticationSessionWrapper;
import at.gv.egovernment.moa.id.auth.modules.eidas.Constants;
import at.gv.egovernment.moa.id.auth.modules.eidas.engine.MOAeIDASChainingMetadataProvider;
import at.gv.egovernment.moa.id.auth.modules.eidas.exceptions.EIDASEngineException;
import at.gv.egovernment.moa.id.auth.modules.eidas.exceptions.EIDASResponseNotSuccessException;
import at.gv.egovernment.moa.id.auth.modules.eidas.utils.SAMLEngineUtils;
import at.gv.egovernment.moa.id.commons.api.data.AuthProzessDataConstants;
import at.gv.egovernment.moa.id.commons.api.exceptions.MOAIDException;
import at.gv.egovernment.moa.id.commons.db.ex.MOADatabaseException;
import at.gv.egovernment.moa.id.protocols.eidas.validator.eIDASResponseValidator;
import at.gv.egovernment.moa.id.protocols.pvp2x.PVPConstants;
import at.gv.egovernment.moa.logging.Logger;
import at.gv.egovernment.moa.util.MiscUtil;
import eu.eidas.auth.commons.EidasStringUtil;
import eu.eidas.auth.commons.protocol.IAuthenticationResponse;
import eu.eidas.auth.engine.ProtocolEngineI;
import eu.eidas.engine.exceptions.EIDASSAMLEngineException;

@Component("ReceiveAuthnResponseTask")
public class ReceiveAuthnResponseTask extends AbstractAuthServletTask {

	@Autowired(required=true) MOAeIDASChainingMetadataProvider eIDASMetadataProvider;
	
	@Override
	public void execute(ExecutionContext executionContext, HttpServletRequest request, HttpServletResponse response) throws TaskExecutionException {

		try{			 
			//get SAML Response
			String base64SamlToken = request.getParameter("SAMLResponse");
			if (MiscUtil.isEmpty(base64SamlToken)) {
				Logger.warn("No eIDAS SAMLReponse found in http request.");
				throw new MOAIDException("HTTP request includes no eIDAS SAML-Response element.", null);
				
			}
			
			//get MOASession
			//defaultTaskInitialization(request, executionContext);
			
			//decode SAML response
			byte[] decSamlToken = EidasStringUtil.decodeBytesFromBase64(base64SamlToken);		
			
			//get eIDAS SAML-engine
			ProtocolEngineI engine = SAMLEngineUtils.createSAMLEngine(eIDASMetadataProvider);
						
			//validate SAML token
			//TODO: maybe add whitelist
			IAuthenticationResponse samlResp = engine.unmarshallResponseAndValidate(decSamlToken, 
					request.getRemoteHost(), 
					Constants.CONFIG_PROPS_SKEWTIME_BEFORE, 
					Constants.CONFIG_PROPS_SKEWTIME_AFTER,
					pendingReq.getAuthURL() + Constants.eIDAS_HTTP_ENDPOINT_METADATA,
					null,
					false);
												
			if (samlResp.isEncrypted()) {
				Logger.info("Received encrypted eIDAS SAML-Response.");
				//TODO: check if additional decryption operation is required
				
			}

						
			//check response StatusCode
			if (!samlResp.getStatusCode().equals(StatusCode.SUCCESS_URI)) {
				Logger.info("Receice eIDAS Response with StatusCode:" + samlResp.getStatusCode()
				+ " Subcode:" + samlResp.getSubStatusCode() + " Msg:" + samlResp.getStatusMessage());
				throw new EIDASResponseNotSuccessException("eIDAS.11", new Object[]{samlResp.getStatusMessage()});
				
			}

			// **********************************************************
			// *******   MOA-ID specific response validation   **********
			// **********************************************************
			String spCountry = authConfig.getBasicConfiguration(Constants.CONIG_PROPS_EIDAS_NODE_COUNTRYCODE, "AT");
			eIDASResponseValidator.validateResponse(pendingReq, samlResp, spCountry);

			
			// **********************************************************
			// ******* Store resonse infos into session object **********
			// **********************************************************
			
			//update MOA-Session data with received information			
			Logger.debug("Store eIDAS response information into MOA-session.");					
			AuthenticationSessionWrapper session = pendingReq.getSessionData(AuthenticationSessionWrapper.class);			
			session.setGenericDataToSession(AuthProzessDataConstants.VALUE_QAALEVEL, samlResp.getLevelOfAssurance());			
			session.setGenericDataToSession(
					AuthenticationSessionStorageConstants.eIDAS_ATTRIBUTELIST, 
					samlResp.getAttributes());						
			session.setGenericDataToSession(
					AuthenticationSessionStorageConstants.eIDAS_RESPONSE, 
					decSamlToken);
			
			//set issuer nation as PVP attribute into MOASession
			session.setGenericDataToSession(PVPConstants.EID_ISSUING_NATION_NAME, samlResp.getCountry());			
			
			//store MOA-session to database
			requestStoreage.storePendingRequest(pendingReq);
			
			revisionsLogger.logEvent(pendingReq, 
					MOAIDEventConstants.AUTHPROCESS_PEPS_RECEIVED,
					samlResp.getId());
		
		} catch (MOAIDException e) {
			throw new TaskExecutionException(pendingReq, "eIDAS Response processing FAILED.", e);
			
		}catch (EIDASSAMLEngineException e) {
			Logger.warn("eIDAS Response validation FAILED.", e);
			Logger.debug("eIDAS response was: " + request.getParameter("SAMLResponse"));
			revisionsLogger.logEvent(pendingReq, 
					MOAIDEventConstants.AUTHPROCESS_PEPS_RECEIVED_ERROR);
			throw new TaskExecutionException(pendingReq, "eIDAS Response processing FAILED.", 
					new EIDASEngineException("eIDAS.09", new Object[]{e.getMessage()}, e));
					
		} catch (MOADatabaseException e) {
			revisionsLogger.logEvent(pendingReq, 
					MOAIDEventConstants.AUTHPROCESS_PEPS_RECEIVED_ERROR);
			throw new TaskExecutionException(pendingReq, "eIDAS Response processing FAILED.", 
					new MOAIDException("init.04", new Object[]{""}, e));
			
		} catch (Exception e) {
			Logger.warn("eIDAS Response processing FAILED.", e);
			revisionsLogger.logEvent(pendingReq, 
					MOAIDEventConstants.AUTHPROCESS_PEPS_RECEIVED_ERROR);
			throw new TaskExecutionException(pendingReq, e.getMessage(), 
					new MOAIDException("eIDAS.10", new Object[]{e.getMessage()}, e));
			
		}	
		
	}

}