/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you 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://opensource.org/licenses/ecl2.txt
   *
   * 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.opencastproject.workflow.handler.distribution;
  
  import static org.opencastproject.workflow.handler.distribution.EngagePublicationChannel.CHANNEL_ID;
  
  import org.opencastproject.distribution.api.DistributionException;
  import org.opencastproject.distribution.api.DownloadDistributionService;
  import org.opencastproject.distribution.api.StreamingDistributionService;
  import org.opencastproject.job.api.Job;
  import org.opencastproject.job.api.JobContext;
  import org.opencastproject.mediapackage.MediaPackage;
  import org.opencastproject.mediapackage.MediaPackageElement;
  import org.opencastproject.mediapackage.Publication;
  import org.opencastproject.search.api.SearchService;
  import org.opencastproject.serviceregistry.api.ServiceRegistry;
  import org.opencastproject.util.NotFoundException;
  import org.opencastproject.workflow.api.AbstractWorkflowOperationHandler;
  import org.opencastproject.workflow.api.WorkflowInstance;
  import org.opencastproject.workflow.api.WorkflowOperationException;
  import org.opencastproject.workflow.api.WorkflowOperationHandler;
  import org.opencastproject.workflow.api.WorkflowOperationResult;
  import org.opencastproject.workflow.api.WorkflowOperationResult.Action;
  
  import org.osgi.service.component.ComponentContext;
  import org.osgi.service.component.annotations.Activate;
  import org.osgi.service.component.annotations.Component;
  import org.osgi.service.component.annotations.Reference;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.Set;
  import java.util.stream.Collectors;
  
  /**
   * Workflow operation for retracting a media package from the engage player.
   */
  @Component(
      immediate = true,
      service = WorkflowOperationHandler.class,
      property = {
          "service.description=Engage Retraction Workflow Operation Handler",
          "workflow.operation=retract-engage"
      }
  )
  public class RetractEngageWorkflowOperationHandler extends AbstractWorkflowOperationHandler {
  
    /** The logging facility */
    private static final Logger logger = LoggerFactory.getLogger(RetractEngageWorkflowOperationHandler.class);
  
    /** The streaming distribution service */
    protected StreamingDistributionService streamingDistributionService = null;
  
    /** The download distribution service */
    protected DownloadDistributionService downloadDistributionService = null;
  
    /** The search service */
    protected SearchService searchService = null;
  
    /**
     * Callback for the OSGi declarative services configuration.
     *
     * @param streamingDistributionService
     *          the streaming distribution service
     */
    @Reference(target = "(distribution.channel=streaming)")
    protected void setStreamingDistributionService(StreamingDistributionService streamingDistributionService) {
      this.streamingDistributionService = streamingDistributionService;
    }
  
    /**
     * Callback for the OSGi declarative services configuration.
     *
     * @param downloadDistributionService
     *          the download distribution service
     */
 
   @Reference(target = "(distribution.channel=download)")
   protected void setDownloadDistributionService(DownloadDistributionService downloadDistributionService) {
     this.downloadDistributionService = downloadDistributionService;
   }
 
   /**
    * Callback for declarative services configuration that will introduce us to the search service. Implementation
    * assumes that the reference is configured as being static.
    *
    * @param searchService
    *          an instance of the search service
    */
 
   @Reference
   protected void setSearchService(SearchService searchService) {
     this.searchService = searchService;
   }
 
   @Reference
   @Override  public void setServiceRegistry(ServiceRegistry serviceRegistry) {
     super.setServiceRegistry(serviceRegistry);
   }
 
   @Override
   @Activate
   protected void activate(ComponentContext cc) {
     super.activate(cc);
   }
 
   /**
    * Generate the jobs retracted the selected elements
    * @param retractElementIds The list of element ids to retract
    * @param searchMediaPackage The mediapackage from the search service
    * @return
    * @throws DistributionException
    */
   protected List<Job> retractElements(Set<String> retractElementIds, MediaPackage searchMediaPackage) throws
           DistributionException {
     if (retractElementIds.isEmpty()) {
       return Collections.emptyList();
     }
 
     List<Job> jobs = new ArrayList<>();
 
     jobs.add(downloadDistributionService.retract(CHANNEL_ID, searchMediaPackage, retractElementIds));
 
     if (streamingDistributionService != null && streamingDistributionService.publishToStreaming()) {
       jobs.add(streamingDistributionService.retract(CHANNEL_ID, searchMediaPackage, retractElementIds));
     }
 
     return jobs;
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.WorkflowOperationHandler#start(WorkflowInstance, JobContext)
    */
   @Override
   public WorkflowOperationResult start(WorkflowInstance workflowInstance, JobContext context)
           throws WorkflowOperationException {
     MediaPackage mediaPackage = workflowInstance.getMediaPackage();
     List<Job> jobs;
     try {
       MediaPackage searchMediaPackage = null;
       try {
         searchMediaPackage = searchService.get(mediaPackage.getIdentifier().toString());
       } catch (NotFoundException e) {
         logger.info("The search service doesn't know media package {}", mediaPackage);
         return createResult(mediaPackage, Action.SKIP);
       }
       logger.info("Retracting media package {} from download/streaming distribution channel", searchMediaPackage);
       var retractElementIds = Arrays.stream(searchMediaPackage.getElements())
           .map(MediaPackageElement::getIdentifier)
           .collect(Collectors.toSet());
       jobs = retractElements(retractElementIds, searchMediaPackage);
 
       // Wait for retraction to finish
       if (!waitForStatus(jobs.toArray(new Job[0])).isSuccess()) {
         throw new WorkflowOperationException("One of the download/streaming retract job did not complete successfully");
       }
 
       logger.debug("Retraction operation complete");
 
       logger.info("Removing media package {} from the search index", mediaPackage);
       Job deleteFromSearch = searchService.delete(mediaPackage.getIdentifier().toString());
       if (!waitForStatus(deleteFromSearch).isSuccess()) {
         throw new WorkflowOperationException("Removing media package from search did not complete successfully");
       }
 
       logger.debug("Remove from search operation complete");
 
       // Remove publication element
       logger.info("Removing engage publication element from media package {}", mediaPackage);
       Publication[] publications = mediaPackage.getPublications();
       for (Publication publication : publications) {
         if (CHANNEL_ID.equals(publication.getChannel())) {
           mediaPackage.remove(publication);
           logger.debug("Remove engage publication element '{}' complete", publication);
         }
       }
 
       return createResult(mediaPackage, Action.CONTINUE);
     } catch (Throwable t) {
       throw new WorkflowOperationException(t);
     }
   }
 
 }