/*

  * Copyright 2007-2010 The Kuali Foundation

  *

  * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php

  *

  * 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.kuali.rice.ksb.messaging.serviceexporters;

 import java.util.List;

 import org.apache.cxf.Bus;

 import org.apache.cxf.endpoint.Server;

 import org.apache.cxf.endpoint.ServerRegistry;

 import org.apache.log4j.Logger;

 import org.kuali.rice.ksb.api.bus.ServiceDefinition;

 import org.kuali.rice.ksb.messaging.bam.BAMServerProxy;

 import org.kuali.rice.ksb.messaging.servlet.CXFServletControllerAdapter;

 /**

  * Abstract ServiceExporter for web services 

  * 

  * @author Kuali Rice Team (rice.collab@kuali.org)

  *

  */

 public abstract class AbstractWebServiceExporter implements ServiceExporter {

     static final Logger LOG = Logger.getLogger(AbstractWebServiceExporter.class);

     private final ServiceDefinition serviceDefinition;

     private final Bus cxfBus;

     private final ServerRegistry cxfServerRegistry;

     protected abstract void publishService(ServiceDefinition serviceDefinition, Object serviceImpl, String address) throws Exception;

     public AbstractWebServiceExporter(ServiceDefinition serviceDefinition, Bus cxfBus, ServerRegistry cxfServerRegistry) {

         this.serviceDefinition = serviceDefinition;

         this.cxfBus = cxfBus;

         this.cxfServerRegistry = cxfServerRegistry;

     }

     @Override

     public Object exportService(ServiceDefinition serviceDefinition) {

             try {                        

                     String serviceAddress = getServiceAddress(serviceDefinition);

                     //Publish the CXF service if it hasn't already been published

                     if (!(isServicePublished(serviceAddress))){

                             publishService(serviceDefinition, serviceDefinition.getService(), serviceAddress);

                     }

                     //Create a CXF mvc controller for this service

                     CXFServletControllerAdapter cxfController = new CXFServletControllerAdapter();

                     return BAMServerProxy.wrap(cxfController, serviceDefinition);

             } catch (Exception e) {

                     throw new RuntimeException(e);

             }

     }

     /**

      * @return the address where the service is (or will be) published

      */

     protected String getServiceAddress(ServiceDefinition serviceDefinition) {

         //Determine endpoint address to publish service on

         String serviceAddress = serviceDefinition.getServicePath();

         if (("/").equals(serviceAddress)){

                 serviceAddress = serviceAddress + serviceDefinition.getServiceName().getLocalPart();

         } else {

                 serviceAddress = serviceAddress + "/" + serviceDefinition.getServiceName().getLocalPart();

         }

         return serviceAddress;

     }

     /** 

      * This determines if the service has already been published on the CXF bus.

      * 

      * @return true if cxf server exists for this service.

      */

     protected boolean isServicePublished(String serviceAddress) {

             ServerRegistry serverRegistry = getCXFServerRegistry();

             List<Server> servers = serverRegistry.getServers();

             for (Server server:servers){                

                     String endpointAddress = server.getEndpoint().getEndpointInfo().getAddress();

                     if (endpointAddress.equals(serviceAddress)){

                             LOG.info("Service already published on CXF, not republishing: " + serviceAddress);

                             return true;

                     }                

             }

             return false;

     }

     protected ServiceDefinition getServiceDefinition() {

             return this.serviceDefinition;

     }

     protected Bus getCXFBus() {

             return this.cxfBus;

     }

     protected ServerRegistry getCXFServerRegistry() {

             return this.cxfServerRegistry;

     }

 }