/*
    * Copyright 2010 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.commons.ihe.ws.correlation;
  
  import net.sf.ehcache.Ehcache;
  import net.sf.ehcache.Element;
  import org.openehealth.ipf.commons.ihe.ws.cxf.audit.WsAuditDataset;
  
  import java.io.Serializable;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * Ehcache-based implementation of asynchronous message correlator.
   * @author Dmytro Rud
   */
  public class EhcacheAsynchronyCorrelator<AuditDatasetType extends WsAuditDataset> implements AsynchronyCorrelator<AuditDatasetType> {
  
      private static final String SERVICE_ENDPOINT_URI_SUFFIX = ".serviceEndpoint";
      private static final String CORRELATION_KEY_SUFFIX      = ".correlationKey";
      private static final String AUDIT_DATASET_SUFFIX        = ".auditDataset";
      private static final String ALTERNATIVE_KEY_SUFFIX      = ".alternativeKey";
      private static final String ALTERNATIVE_KEYS_SUFFIX     = ".alternativeKeys";
  
      private final Ehcache ehcache;
  
      public EhcacheAsynchronyCorrelator(Ehcache ehcache) {
          this.ehcache = requireNonNull(ehcache, "ehcache instance");
      }
  
      private void put(String key, String suffix, Serializable value) {
          ehcache.put(new Element(key + suffix, value));
      }
  
      private <T extends Serializable> T get(String key, String suffix) {
          Element element = ehcache.get(key + suffix);
          return (element != null) ? (T) element.getObjectValue() : null;
      }
  
      @Override
      public void storeServiceEndpointUri(String messageId, String serviceEndpointUri) {
          put(messageId, SERVICE_ENDPOINT_URI_SUFFIX, requireNonNull(serviceEndpointUri, "service endpoint URI"));
      }
  
      @Override
      public void storeCorrelationKey(String messageId, String correlationKey) {
          put(messageId, CORRELATION_KEY_SUFFIX, requireNonNull(correlationKey, "correlation key"));
      }
  
      @Override
      public void storeAuditDataset(String messageId, WsAuditDataset auditDataset) {
          put(messageId, AUDIT_DATASET_SUFFIX, requireNonNull(auditDataset, "audit dataset"));
      }
  
      @Override
      public String getServiceEndpointUri(String messageId) {
          return get(messageId, SERVICE_ENDPOINT_URI_SUFFIX);
      }
  
      @Override
      public String getCorrelationKey(String messageId) {
          return get(messageId, CORRELATION_KEY_SUFFIX);
      }
  
      @Override
      public AuditDatasetType getAuditDataset(String messageId) {
          return get(messageId, AUDIT_DATASET_SUFFIX);
      }
  
      @Override
      public void storeAlternativeKeys(String messageId, String... alternativeKeys) {
          requireNonNull(alternativeKeys, "alternative keys should be not null");
          for (String key : alternativeKeys) {
              put(key, ALTERNATIVE_KEY_SUFFIX, messageId);
          }
          put(messageId, ALTERNATIVE_KEYS_SUFFIX, alternativeKeys);
      }
  
      @Override
      public String getMessageId(String alternativeKey) {
          return get(alternativeKey, ALTERNATIVE_KEY_SUFFIX);
      }
  
      @Override
      public boolean delete(String messageId) {
          String[] alternativeKeys = get(messageId, ALTERNATIVE_KEYS_SUFFIX);
         if (alternativeKeys != null) {
             for (String key : alternativeKeys) {
                 ehcache.remove(key + ALTERNATIVE_KEY_SUFFIX);
             }
         }
         ehcache.remove(messageId + ALTERNATIVE_KEYS_SUFFIX);
         ehcache.remove(messageId + CORRELATION_KEY_SUFFIX);
         ehcache.remove(messageId + AUDIT_DATASET_SUFFIX);
         return ehcache.remove(messageId + SERVICE_ENDPOINT_URI_SUFFIX);
     }
 }