/*
    * Copyright 2018 the original author or authors.
    *
    *  Licensed under the Apache License, Version 2.0 (the "License");
    *  you may not use this file except in compliance with the License.
    *  You may obtain a copy of the License at
    *
    *         http://www.apache.org/licenses/LICENSE-2.0
    *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   */
  
  package org.openehealth.ipf.platform.camel.ihe.fhir.iti68;
  
  import org.apache.camel.Exchange;
  import org.openehealth.ipf.commons.audit.AuditContext;
  import org.openehealth.ipf.commons.audit.codes.EventOutcomeIndicator;
  import org.openehealth.ipf.commons.ihe.core.atna.AuditStrategy;
  import org.openehealth.ipf.commons.ihe.fhir.iti68.Iti68AuditDataset;
  import org.openehealth.ipf.platform.camel.ihe.atna.interceptor.AuditInterceptor;
  import org.openehealth.ipf.platform.camel.ihe.core.InterceptorSupport;
  import org.openehealth.ipf.platform.camel.ihe.fhir.core.intercept.consumer.AuditInterceptorUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import javax.servlet.http.HttpServletRequest;
  
  /**
   * Audit Interceptor for ITI-68. Note that the ParticipantObjectIdentificationType for the document
   * is not populated automatically, because the location of the parametzers depends upon the actual
   * implementation. The AuditDataset is forwarded in the Camel message header "AuditDataset" so that
   * at least {@link Iti68AuditDataset#documentUniqueId} can be set.
   *
   * @author Christian Ohr
   * @since 3.5
   */
  class Iti68ConsumerAuditInterceptor
          extends InterceptorSupport<Iti68Endpoint>
          implements AuditInterceptor<Iti68AuditDataset, Iti68Endpoint> {
  
      private static final Logger LOG = LoggerFactory.getLogger(Iti68ConsumerAuditInterceptor.class);
  
      private final AuditContext auditContext;
  
      Iti68ConsumerAuditInterceptor(AuditContext auditContext) {
          this.auditContext = auditContext;
      }
  
      @Override
      public AuditStrategy<Iti68AuditDataset> getAuditStrategy() {
          return getEndpoint().getServerAuditStrategy();
      }
  
      @Override
      public void determineParticipantsAddresses(Exchange exchange, Iti68AuditDataset auditDataset) {
      }
  
      @Override
      public void process(Exchange exchange) throws Exception {
          Iti68AuditDataset auditDataset = createAndEnrichAuditDatasetFromRequest(getAuditStrategy(), exchange, exchange.getIn().getBody());
          determineParticipantsAddresses(exchange, auditDataset);
  
          // Add audit dataset to the exchange headers so that a processing route could add things like
          // document id, repository id etc. This is because this information may be present (in case of
          // FHIR/XDS bridges) in the request URI, but there is no definition HOW.
          exchange.getIn().setHeader(AUDIT_DATASET_HEADER, auditDataset);
  
          boolean failed = false;
          try {
              getWrappedProcessor().process(exchange);
              failed = exchange.isFailed();
              // Do not check the body, because it's a stream
          } catch (Exception e) {
              if (auditDataset != null) {
                  auditDataset.setEventOutcomeDescription(e.getMessage());
              }
              throw e;
          } finally {
              if (auditDataset != null) {
                  auditDataset.setEventOutcomeIndicator(failed ?
                          EventOutcomeIndicator.MajorFailure :
                          EventOutcomeIndicator.Success);
                  getAuditStrategy().doAudit(auditContext, auditDataset);
              }
          }
      }
  
      /**
       * Creates a new audit dataset and enriches it with data from the request
       * message.  All exception are ignored.
       *
       * @return newly created audit dataset or <code>null</code> when creation failed.
       */
      private Iti68AuditDataset createAndEnrichAuditDatasetFromRequest(AuditStrategy<Iti68AuditDataset> strategy, Exchange exchange, Object msg) {
          try {
             Iti68AuditDataset auditDataset = strategy.createAuditDataset();
 
             HttpServletRequest request = exchange.getIn().getHeader(Exchange.HTTP_SERVLET_REQUEST, HttpServletRequest.class);
             auditDataset.setSourceUserId("unknown");
             auditDataset.setDestinationUserId(request.getRequestURL().toString());
             auditDataset.setRemoteAddress(request.getRemoteAddr());
 
             // TODO Also extract basic auth user?
             AuditInterceptorUtils.extractClientCertificateCommonName(exchange, auditDataset);
 
             return strategy.enrichAuditDatasetFromRequest(auditDataset, msg, exchange.getIn().getHeaders());
         } catch (Exception e) {
             LOG.error("Exception when enriching audit dataset from request", e);
             return null;
         }
     }
 
 }