/**
   * This service method will return back all available password validation regular expressions
   * against the corresponding domain names.
   *
   * @return
   * @throws IdentityException
   */
  public PasswordRegExDTO[] getPasswordRegularExpressions() throws IdentityException {
    UserRealm realm = null;
    realm = IdentityTenantUtil.getRealm(null, null);
    List<PasswordRegExDTO> passwordRegExList = new ArrayList<PasswordRegExDTO>();
    PasswordRegExDTO passwordRegEx;

    try {

      UserStoreManager manager = realm.getUserStoreManager();
      String domainName;
      String regEx;

      while (manager != null) {
        domainName =
            manager
                .getRealmConfiguration()
                .getUserStoreProperty(UserCoreConstants.RealmConfig.PROPERTY_DOMAIN_NAME);
        regEx =
            manager
                .getRealmConfiguration()
                .getUserStoreProperty(UserCoreConstants.RealmConfig.PROPERTY_JS_REG_EX);
        if (regEx != null && regEx.length() > 0) {
          passwordRegEx = new PasswordRegExDTO();
          passwordRegEx.setDomainName(domainName);
          passwordRegEx.setRegEx(regEx);
          passwordRegExList.add(passwordRegEx);
        }
        manager = manager.getSecondaryUserStoreManager();
      }

    } catch (UserStoreException e) {
      log.error(e);
      throw new IdentityException(
          "Error occured while loading password validation regular expressions.");
    }

    return passwordRegExList.toArray(new PasswordRegExDTO[passwordRegExList.size()]);
  }
  @Override
  protected void processAuthenticationResponse(
      HttpServletRequest request, HttpServletResponse response, AuthenticationContext context)
      throws AuthenticationFailedException {

    try {

      Map<String, String> authenticatorProperties = context.getAuthenticatorProperties();

      String clientId = authenticatorProperties.get(OIDCAuthenticatorConstants.CLIENT_ID);
      String clientSecret = authenticatorProperties.get(OIDCAuthenticatorConstants.CLIENT_SECRET);
      String tokenEndPoint = getTokenEndpoint(authenticatorProperties);

      if (tokenEndPoint == null) {
        tokenEndPoint = authenticatorProperties.get(OIDCAuthenticatorConstants.OAUTH2_TOKEN_URL);
      }

      String callbackUrl = getCallbackUrl(authenticatorProperties);

      if (StringUtils.isBlank(callbackUrl)) {
        callbackUrl = IdentityUtil.getServerURL(FrameworkConstants.COMMONAUTH, true, true);
      }

      @SuppressWarnings({"unchecked"})
      Map<String, String> paramValueMap =
          (Map<String, String>) context.getProperty("oidc:param.map");

      if (paramValueMap != null && paramValueMap.containsKey("redirect_uri")) {
        callbackUrl = paramValueMap.get("redirect_uri");
      }

      OAuthAuthzResponse authzResponse = OAuthAuthzResponse.oauthCodeAuthzResponse(request);
      String code = authzResponse.getCode();

      OAuthClientRequest accessRequest =
          getaccessRequest(tokenEndPoint, clientId, code, clientSecret, callbackUrl);

      // Create OAuth client that uses custom http client under the hood
      OAuthClient oAuthClient = new OAuthClient(new URLConnectionClient());
      OAuthClientResponse oAuthResponse = getOauthResponse(oAuthClient, accessRequest);

      // TODO : return access token and id token to framework
      String accessToken = oAuthResponse.getParam(OIDCAuthenticatorConstants.ACCESS_TOKEN);

      if (StringUtils.isBlank(accessToken)) {
        throw new AuthenticationFailedException("Access token is empty or null");
      }

      String idToken = oAuthResponse.getParam(OIDCAuthenticatorConstants.ID_TOKEN);

      if (StringUtils.isBlank(idToken) && requiredIDToken(authenticatorProperties)) {
        throw new AuthenticationFailedException("Id token is required and is missing");
      }

      context.setProperty(OIDCAuthenticatorConstants.ACCESS_TOKEN, accessToken);

      AuthenticatedUser authenticatedUserObj;
      Map<ClaimMapping, String> claims = new HashMap<>();
      Map<String, Object> jsonObject = new HashMap<>();

      if (StringUtils.isNotBlank(idToken)) {

        context.setProperty(OIDCAuthenticatorConstants.ID_TOKEN, idToken);

        String base64Body = idToken.split("\\.")[1];
        byte[] decoded = Base64.decodeBase64(base64Body.getBytes());
        String json = new String(decoded);

        jsonObject = JSONUtils.parseJSON(json);

        if (jsonObject == null) {

          if (log.isDebugEnabled()) {
            log.debug("Decoded json object is null");
          }

          throw new AuthenticationFailedException("Decoded json object is null");
        }

        if (log.isDebugEnabled()
            && IdentityUtil.isTokenLoggable(IdentityConstants.IdentityTokens.USER_ID_TOKEN)) {
          log.debug("Retrieved the User Information:" + jsonObject);
        }

        String authenticatedUser = null;
        String isSubjectInClaimsProp =
            context
                .getAuthenticatorProperties()
                .get(IdentityApplicationConstants.Authenticator.SAML2SSO.IS_USER_ID_IN_CLAIMS);

        if (StringUtils.equalsIgnoreCase("true", isSubjectInClaimsProp)) {

          authenticatedUser = getSubjectFromUserIDClaimURI(context);

          if (authenticatedUser == null && log.isDebugEnabled()) {
            log.debug(
                "Subject claim could not be found amongst subject attributes. "
                    + "Defaulting to the sub attribute in IDToken.");
          }
        }

        if (authenticatedUser == null) {

          authenticatedUser = getAuthenticateUser(context, jsonObject, oAuthResponse);

          if (authenticatedUser == null) {
            throw new AuthenticationFailedException("Cannot find federated User Identifier");
          }
        }

        String attributeSeparator = null;

        try {

          String tenantDomain = context.getTenantDomain();

          if (StringUtils.isBlank(tenantDomain)) {
            tenantDomain = MultitenantConstants.SUPER_TENANT_DOMAIN_NAME;
          }

          int tenantId =
              OpenIDConnectAuthenticatorServiceComponent.getRealmService()
                  .getTenantManager()
                  .getTenantId(tenantDomain);
          UserRealm userRealm =
              OpenIDConnectAuthenticatorServiceComponent.getRealmService()
                  .getTenantUserRealm(tenantId);

          if (userRealm != null) {
            UserStoreManager userStore = (UserStoreManager) userRealm.getUserStoreManager();
            attributeSeparator =
                userStore
                    .getRealmConfiguration()
                    .getUserStoreProperty(IdentityCoreConstants.MULTI_ATTRIBUTE_SEPARATOR);
            if (log.isDebugEnabled()) {
              log.debug(
                  "For the claim mapping: "
                      + attributeSeparator
                      + " is used as the attributeSeparator in tenant: "
                      + tenantDomain);
            }
          }

        } catch (UserStoreException e) {
          throw new AuthenticationFailedException(
              "Error while retrieving multi attribute " + "separator", e);
        }

        for (Map.Entry<String, Object> entry : jsonObject.entrySet()) {
          buildClaimMappings(claims, entry, attributeSeparator);
        }

        authenticatedUserObj =
            AuthenticatedUser.createFederateAuthenticatedUserFromSubjectIdentifier(
                authenticatedUser);
      } else {

        if (log.isDebugEnabled()) {
          log.debug("The IdToken is null");
        }

        authenticatedUserObj =
            AuthenticatedUser.createFederateAuthenticatedUserFromSubjectIdentifier(
                getAuthenticateUser(context, jsonObject, oAuthResponse));
      }

      claims.putAll(getSubjectAttributes(oAuthResponse, authenticatorProperties));
      authenticatedUserObj.setUserAttributes(claims);

      context.setSubject(authenticatedUserObj);

    } catch (OAuthProblemException e) {
      throw new AuthenticationFailedException("Authentication process failed", e);
    }
  }