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

import static at.gv.egovernment.moa.id.auth.MOAIDAuthConstants.*;
import iaik.x509.X509Certificate;

import java.io.IOException;
import java.util.Map;

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

import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.lang.StringEscapeUtils;

import at.gv.egovernment.moa.id.auth.AuthenticationServer;
import at.gv.egovernment.moa.id.auth.builder.DataURLBuilder;
import at.gv.egovernment.moa.id.auth.data.AuthenticationSession;
import at.gv.egovernment.moa.id.auth.exception.AuthenticationException;
import at.gv.egovernment.moa.id.auth.exception.MOAIDException;
import at.gv.egovernment.moa.id.auth.exception.WrongParametersException;
import at.gv.egovernment.moa.id.commons.db.ConfigurationDBUtils;
import at.gv.egovernment.moa.id.commons.db.ex.MOADatabaseException;
import at.gv.egovernment.moa.id.storage.AuthenticationSessionStoreage;
import at.gv.egovernment.moa.id.util.ParamValidatorUtils;
import at.gv.egovernment.moa.id.util.ServletUtils;
import at.gv.egovernment.moa.logging.Logger;
import at.gv.egovernment.moa.spss.util.CertificateUtils;

import com.datentechnik.process_engine.api.ExecutionContext;

/**
 * Parses the certificate from {@code InfoBoxReadResponse} (via POST parameter {@link MOAIDAuthConstants#PARAM_XMLRESPONSE}), creates the auth block to be signed and returns a {@code CreateXMLSignatureRequest} for auth block signature.<p/>
 * In detail:
 * <ul>
 * <li>Renames the moa session id.</li>
 * <li>Retrieves the certificate via {@code InfoBoxReadResponse} from POST parameter {@link MOAIDAuthConstants#PARAM_XMLRESPONSE}.</li>
 * <li>Verifies the certificate.</li>
 * <li>Creates the auth block to be signed using information from the certificate (Organwalter, foreign citizen.</li>
 * <li>Puts it in a {@code CreateXMLSignatureRequest}.</li>
 * <li>Updates moa session.</li>
 * <li>Responds with {@code CreateXMLSignatureRequest}.</li>
 * </ul>
 * Expects:
 * <ul>
 * <li>HttpServletRequest parameter {@link MOAIDAuthConstants#PARAM_SESSIONID}</li>
 * <li>HttpServletRequest parameter {@link MOAIDAuthConstants#PARAM_XMLRESPONSE} containing a {@code InfoBoxReadResponse}.</li>
 * </ul>
 * Result:
 * <ul>
 * <li>{@code CreateXMLSignatureRequest} send as HttpServletResponse (for CCE).</li>
 * </ul>
 * Code taken from {@link at.gv.egovernment.moa.id.auth.servlet.VerifyCertificateServlet}.
 * @author tknall
 * @see #execute(ExecutionContext, HttpServletRequest, HttpServletResponse)
 *
 */
public class VerifyCertificateTask extends AbstractAuthServletTask {

	@Override
	public void execute(ExecutionContext executionContext, HttpServletRequest req, HttpServletResponse resp)
			throws Exception {

		// note: code taken from at.gv.egovernment.moa.id.auth.servlet.VerifyCertificateServlet

		Logger.debug("POST VerifyCertificateServlet");
		
		String pendingRequestID = null;
		
		Map<String, String> parameters;
	    try 
	    {
	      parameters = getParameters(req);
	    } catch (FileUploadException e) 
	    {
	      Logger.error("Parsing mulitpart/form-data request parameters failed: " + e.getMessage());
	      throw new IOException(e.getMessage());
	     	}
	    String sessionID = req.getParameter(PARAM_SESSIONID);
	    
	    // escape parameter strings
		sessionID = StringEscapeUtils.escapeHtml(sessionID);
		
		pendingRequestID = AuthenticationSessionStoreage.getPendingRequestID(sessionID);
		
	    AuthenticationSession session = null;
	    try {
	       // check parameter
	       if (!ParamValidatorUtils.isValidSessionID(sessionID))
	          throw new WrongParametersException("VerifyCertificate", PARAM_SESSIONID, "auth.12");
	       
	    	session = AuthenticationServer.getSession(sessionID);
	    	
	        //change MOASessionID
	        sessionID = AuthenticationSessionStoreage.changeSessionID(session);
	    	
    		X509Certificate cert = AuthenticationServer.getInstance().getCertificate(sessionID, parameters);
    		if (cert == null) {
    			Logger.error("Certificate could not be read.");
    			throw new AuthenticationException("auth.14", null);    		
    		}
    		
	    	boolean useMandate = session.getUseMandate();
	    	
	    	
	    	if (useMandate) {

	    		// verify certificate for OrganWalter
	    		String createXMLSignatureRequestOrRedirect = AuthenticationServer.getInstance().verifyCertificate(session, cert);
	    		
		    	try {
					AuthenticationSessionStoreage.storeSession(session);
				} catch (MOADatabaseException e) {
					throw new MOAIDException("session store error", null);
				}
	    		
		    	// TODO[branch]: Mandate; respond with CXSR for authblock signature, dataURL "/VerifyAuthBlock"
		    	ServletUtils.writeCreateXMLSignatureRequestOrRedirect(resp, session, createXMLSignatureRequestOrRedirect, AuthenticationServer.REQ_PROCESS_VALIDATOR_INPUT, "VerifyCertificate");
	    		
	    	}
	    	else {
	    			
		    	
	    		String countrycode = CertificateUtils.getIssuerCountry(cert);
	    		if (countrycode != null) {
	    			if (countrycode.compareToIgnoreCase("AT") == 0) {
	    				Logger.error("Certificate issuer country code is \"AT\". Login not support in foreign identities mode.");
	    				throw new AuthenticationException("auth.22", null);
	    			}
	    		}
	    		
	    		// Foreign Identities Modus	
		    	String createXMLSignatureRequest = AuthenticationServer.getInstance().createXMLSignatureRequestForeignID(session, cert);
		      // build dataurl (to the GetForeignIDSerlvet)
		    	String dataurl =
	             new DataURLBuilder().buildDataURL(
	               session.getAuthURL(),
	               REQ_GET_FOREIGN_ID,
	               session.getSessionID());
	       
		    	try {
					AuthenticationSessionStoreage.storeSession(session);
				} catch (MOADatabaseException e) {
					throw new MOAIDException("session store error", null);
				}
		    	
	    		// TODO[branch]: Foreign citizen; respond with CXSR for authblock signature, dataURL "/GetForeignID"
		    	ServletUtils.writeCreateXMLSignatureRequest(resp, session, createXMLSignatureRequest, AuthenticationServer.REQ_PROCESS_VALIDATOR_INPUT, "GetForeignID", dataurl);
		    	
		    	Logger.debug("Send CreateXMLSignatureRequest to BKU");
	    	}	    		    	 
	    }
	    catch (MOAIDException ex) {
	      handleError(null, ex, req, resp, pendingRequestID);
	      
	    } catch (Exception e) {
	    	Logger.error("CertificateValidation has an interal Error.", e);
	    }
	       
	    
	    finally {
	    	ConfigurationDBUtils.closeSession();
	    }

	}

}