package at.asitplus.eidas.specific.modules.auth.idaustria.controller;

import java.io.IOException;

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

import org.apache.commons.lang3.StringUtils;
import org.apache.commons.text.StringEscapeUtils;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import at.asitplus.eidas.specific.modules.auth.idaustria.IdAustriaAuthConstants;
import at.gv.egiz.eaaf.core.exceptions.EaafException;
import at.gv.egiz.eaaf.core.impl.idp.controller.AbstractProcessEngineSignalController;
import lombok.extern.slf4j.Slf4j;

/**
 * Controller that receives the response from ID Austria system.
 *
 * @author tlenz
 *
 */
@Slf4j
@Controller
public class IdAustriaAuthSignalController extends AbstractProcessEngineSignalController {

  public static final String HTTP_PARAM_RELAYSTATE = "RelayState";

  /**
   * Default constructor with logging.
   *
   */
  public IdAustriaAuthSignalController() {
    super();
    log.debug("Registering servlet " + getClass().getName()
        + " with mappings '" + IdAustriaAuthConstants.ENDPOINT_POST
        + "' and '" + IdAustriaAuthConstants.ENDPOINT_REDIRECT + "'.");

  }

  /**
   * HTTP end-point for incoming SAML2 Respone from ID Austrian System.
   *
   * @param req HTTP request
   * @param resp HTTP response
   * @throws IOException In case of a HTTP communication error
   * @throws EaafException In case of a state-validation problem
   */
  @RequestMapping(value = { IdAustriaAuthConstants.ENDPOINT_POST,
      IdAustriaAuthConstants.ENDPOINT_REDIRECT },
      method = { RequestMethod.POST, RequestMethod.GET })
  public void performEidasAuthentication(HttpServletRequest req, HttpServletResponse resp)
      throws IOException, EaafException {
    signalProcessManagement(req, resp);

  }

  /**
   * Read the PendingRequestId from SAML2 RelayState parameter.
   */
  @Override
  public String getPendingRequestId(HttpServletRequest request) {
    String relayState = StringEscapeUtils.escapeHtml4(request.getParameter(HTTP_PARAM_RELAYSTATE));
    if (StringUtils.isNotEmpty(relayState)) {
      try {
        String pendingReqId = transactionStorage.get(relayState, String.class);
        if (StringUtils.isNotEmpty(pendingReqId)) {
          
          return pendingReqId;  
          
        } else {
          log.info("SAML2 RelayState from request is unknown. Can NOT restore session ... ");
          
        }
                                
      } catch (EaafException e) {
        log.error("Can NOT map SAML2 RelayState to pendingRequestId", e);
        
      } finally {
        transactionStorage.remove(relayState);
        
      }
      
    } else {
      log.info("No SAML2 relaystate. Can NOT restore session ... ");
      
    }
        
    return null; 

  }
}