/*
    * Copyright 2009 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.mllp.core;
  
  import org.apache.camel.CamelContext;
  import org.apache.camel.Endpoint;
  import org.apache.camel.component.hl7.HL7MLLPCodec;
  import org.apache.camel.component.mina2.Mina2Component;
  import org.apache.camel.component.mina2.Mina2Endpoint;
  import org.openehealth.ipf.commons.ihe.hl7v2.audit.MllpAuditDataset;
  import org.openehealth.ipf.platform.camel.ihe.core.InterceptableComponent;
  import org.openehealth.ipf.platform.camel.ihe.core.Interceptor;
  import org.openehealth.ipf.platform.camel.ihe.hl7v2.Hl7v2ConfigurationHolder;
  import org.openehealth.ipf.platform.camel.ihe.hl7v2.intercept.consumer.ConsumerAdaptingInterceptor;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.nio.charset.Charset;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  
  /**
   * Generic Camel component for MLLP.
   *
   * @author Dmytro Rud
   */
  public abstract class MllpComponent<ConfigType extends MllpEndpointConfiguration, AuditDatasetType extends MllpAuditDataset>
          extends Mina2Component implements InterceptableComponent, Hl7v2ConfigurationHolder<AuditDatasetType> {
  
      private static final transient Logger LOG = LoggerFactory.getLogger(MllpComponent.class);
  
      public static final String ACK_TYPE_CODE_HEADER = ConsumerAdaptingInterceptor.ACK_TYPE_CODE_HEADER;
  
      private static final String DEFAULT_HL7_CODEC_FACTORY_BEAN_NAME = "#hl7codec";
  
      protected MllpComponent() {
          super();
      }
  
      /**
       * Camel context-based constructor.
       *
       * @param camelContext camel context
       */
      protected MllpComponent(CamelContext camelContext) {
          super(camelContext);
      }
  
  
      /**
       * Creates a configuration object.
       *
       * @param uri endpoint URI
       * @param parameters URL parameters.
       * @return configuration object filled with values from the provided parameter map.
       */
      protected abstract ConfigType createConfig(String uri, Map<String, Object> parameters) throws Exception;
  
      /**
       * Creates a configuration object.
       *
       * @param parameters URL parameters.
       * @return configuration object filled with values from the provided parameter map
       * @deprecated use {@link #createConfig(String, Map)}
       */
      protected ConfigType createConfig(Map<String, Object> parameters) throws Exception {
          return createConfig(MllpEndpointConfiguration.UNKNOWN_URI, parameters);
      }
  
      /**
       * Creates an endpoint object.
       *
       * @param wrappedEndpoint standard Camel MINA2 endpoint instance.
       * @param config          endpoint configuration.
       * @return configured MLLP endpoint instance which wraps the MINA2 one.
       */
      protected abstract MllpEndpoint<?, ?, ?> createEndpoint(Mina2Endpoint wrappedEndpoint, ConfigType config);
  
  
      /**
       * Creates and configures the endpoint.
       */
      @Override
     protected Endpoint createEndpoint(
             String uri,
             String remaining,
             Map<String, Object> parameters) throws Exception {
         // explicitly overwrite some standard camel-mina parameters
         if (parameters.isEmpty()) {
             parameters = new HashMap<>();
         }
         parameters.put("sync", true);
         parameters.put("lazySessionCreation", true);
         parameters.put("transferExchange", false);
         if (!parameters.containsKey("codec")) {
             parameters.put("codec", DEFAULT_HL7_CODEC_FACTORY_BEAN_NAME);
         }
 
         ConfigType config = createConfig(uri, parameters);
 
         Charset charset = null;
         try {
             HL7MLLPCodec codecFactory = (HL7MLLPCodec) config.getCodecFactory();
             if (codecFactory == null) {
                 codecFactory = new HL7MLLPCodec();
                 LOG.warn("No HL7 codec factory found, creating new default instance {}", codecFactory);
             }
             charset = codecFactory.getCharset();
         } catch (ClassCastException cce) {
             LOG.warn("Unsupported HL7 codec factory type {}, using default character set", config.getCodecFactory().getClass().getName());
         }
         if (charset == null) {
             charset = Charset.defaultCharset();
         }
         parameters.put("encoding", charset.name());
 
         // construct the endpoint
         Endpoint endpoint = super.createEndpoint(uri, "tcp://" + remaining, parameters);
         Mina2Endpoint minaEndpoint = (Mina2Endpoint) endpoint;
 
         // wrap and return
         return createEndpoint(minaEndpoint, config);
     }
 
     @Override
     public List<Interceptor<?>> getAdditionalConsumerInterceptors() {
         return Collections.emptyList();
     }
 
     @Override
     public List<Interceptor<?>> getAdditionalProducerInterceptors() {
         return Collections.emptyList();
     }
 
 }