/*
    * 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.transcription.workflowoperation;
  
  import org.opencastproject.composer.api.ComposerService;
  import org.opencastproject.composer.api.EncoderException;
  import org.opencastproject.composer.api.EncodingProfile;
  import org.opencastproject.job.api.Job;
  import org.opencastproject.job.api.JobContext;
  import org.opencastproject.mediapackage.MediaPackage;
  import org.opencastproject.mediapackage.MediaPackageElementFlavor;
  import org.opencastproject.mediapackage.MediaPackageElementParser;
  import org.opencastproject.mediapackage.MediaPackageException;
  import org.opencastproject.mediapackage.Track;
  import org.opencastproject.mediapackage.selector.AbstractMediaPackageElementSelector;
  import org.opencastproject.mediapackage.selector.SimpleElementSelector;
  import org.opencastproject.mediapackage.selector.TrackSelector;
  import org.opencastproject.serviceregistry.api.ServiceRegistry;
  import org.opencastproject.transcription.api.TranscriptionService;
  import org.opencastproject.transcription.api.TranscriptionServiceException;
  import org.opencastproject.util.NotFoundException;
  import org.opencastproject.workflow.api.AbstractWorkflowOperationHandler;
  import org.opencastproject.workflow.api.ConfiguredTagsAndFlavors;
  import org.opencastproject.workflow.api.WorkflowInstance;
  import org.opencastproject.workflow.api.WorkflowOperationException;
  import org.opencastproject.workflow.api.WorkflowOperationHandler;
  import org.opencastproject.workflow.api.WorkflowOperationInstance;
  import org.opencastproject.workflow.api.WorkflowOperationResult;
  import org.opencastproject.workflow.api.WorkflowOperationResult.Action;
  import org.opencastproject.workspace.api.Workspace;
  
  import org.apache.commons.lang3.StringUtils;
  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.io.IOException;
  import java.util.Collection;
  import java.util.List;
  import java.util.SortedMap;
  import java.util.TreeMap;
  
  @Component(
      immediate = true,
      service = WorkflowOperationHandler.class,
      property = {
          "service.description=Start Transcription Workflow Operation Handler (Microsoft Azure)",
          "workflow.operation=microsoft-azure-start-transcription"
      }
  )
  public class MicrosoftAzureStartTranscriptionOperationHandler extends AbstractWorkflowOperationHandler {
  
    private static final Logger logger = LoggerFactory.getLogger(MicrosoftAzureStartTranscriptionOperationHandler.class);
  
    /** Workflow configuration option keys */
    static final String LANGUAGE_KEY = "language";
    static final String SKIP_IF_FLAVOR_EXISTS_KEY = "skip-if-flavor-exists";
    static final String EXTRACT_AUDIO_ENCODING_PROFILE_KEY = "audio-extraction-encoding-profile";
    private static final String DEFAULT_EXTRACT_AUDIO_ENCODING_PROFILE = "transcription-azure.audio";
  
    /** The transcription service */
    private TranscriptionService service = null;
    /** The composer service. */
    private ComposerService composerService;
    /** The workspace. */
    private Workspace workspace;
  
    /** The configuration options for this handler */
    private static final SortedMap<String, String> CONFIG_OPTIONS;
  
    static {
      CONFIG_OPTIONS = new TreeMap<String, String>();
      CONFIG_OPTIONS.put(SOURCE_FLAVORS, "The flavors of the tracks to use as audio input. "
          + "Only the first available track will be used.");
      CONFIG_OPTIONS.put(SOURCE_TAGS, "The tags of the track to use as audio input.");
      CONFIG_OPTIONS.put(LANGUAGE_KEY, "The language the transcription service should use.");
      CONFIG_OPTIONS.put(SKIP_IF_FLAVOR_EXISTS_KEY,
         "If this \"flavor\" is already in the media package, skip this operation.");
     CONFIG_OPTIONS.put(EXTRACT_AUDIO_ENCODING_PROFILE_KEY,
         "The encoding profile to extract audio for transcription.");
   }
 
   @Override
   @Activate
   protected void activate(ComponentContext cc) {
     super.activate(cc);
   }
 
   @Override
   public WorkflowOperationResult start(final WorkflowInstance workflowInstance, JobContext context)
           throws WorkflowOperationException {
     MediaPackage mediaPackage = workflowInstance.getMediaPackage();
     WorkflowOperationInstance operation = workflowInstance.getCurrentOperation();
 
     String skipOption = StringUtils.trimToNull(operation.getConfiguration(SKIP_IF_FLAVOR_EXISTS_KEY));
     if (skipOption != null) {
       SimpleElementSelector elementSelector = new SimpleElementSelector();
       for (String flavorStr : StringUtils.split(skipOption, ",")) {
         if (StringUtils.trimToNull(flavorStr) == null) {
           continue;
         }
         MediaPackageElementFlavor skipFlavor = MediaPackageElementFlavor.parseFlavor(
             StringUtils.trimToEmpty(flavorStr));
         elementSelector.addFlavor(skipFlavor);
       }
       if (!elementSelector.select(mediaPackage, false).isEmpty()) {
         logger.info("Start transcription operation will be skipped for media package '{}' "
             + "because elements with given flavor already exist.", mediaPackage.getIdentifier());
         return createResult(Action.SKIP);
       }
     }
     String encodingProfile = StringUtils.trimToNull(operation.getConfiguration(EXTRACT_AUDIO_ENCODING_PROFILE_KEY));
     if (encodingProfile == null) {
       encodingProfile = DEFAULT_EXTRACT_AUDIO_ENCODING_PROFILE;
     }
     // Check which tags have been configured
     ConfiguredTagsAndFlavors tagsAndFlavors = getTagsAndFlavors(
         workflowInstance, Configuration.many, Configuration.many, Configuration.none, Configuration.none);
     List<MediaPackageElementFlavor> sourceFlavorsOption = tagsAndFlavors.getSrcFlavors();
     List<String> sourceTagsOption = tagsAndFlavors.getSrcTags();
     String language = StringUtils.trimToEmpty(operation.getConfiguration(LANGUAGE_KEY));
     AbstractMediaPackageElementSelector<Track> elementSelector = new TrackSelector();
     // Make sure either one of tags or flavors are provided
     if (sourceTagsOption.isEmpty() && sourceFlavorsOption.isEmpty()) {
       throw new WorkflowOperationException("No source tag or flavor have been specified!");
     }
     if (!sourceFlavorsOption.isEmpty()) {
       for (MediaPackageElementFlavor srcFlavor : sourceFlavorsOption) {
         elementSelector.addFlavor(srcFlavor);
       }
     }
     if (!sourceTagsOption.isEmpty()) {
       for (String srcTag : sourceTagsOption) {
         elementSelector.addTag(StringUtils.trimToEmpty(srcTag));
       }
     }
     Collection<Track> elements = elementSelector.select(mediaPackage, false);
     if (elements.isEmpty()) {
       logger.info("Media package {} does not contain elements to transcribe. Skip operation.",
           mediaPackage.getIdentifier());
       return createResult(Action.SKIP);
     }
     logger.info("Start transcription for media package '{}'.", mediaPackage.getIdentifier());
     Track audioTrack = null;
     try {
       for (Track track : elements) {
         if (!track.hasAudio()) {
           continue;
         }
         try {
           EncodingProfile profile = composerService.getProfile(encodingProfile);
           if (profile == null) {
             throw new WorkflowOperationException("Encoding profile '" + encodingProfile + "' was not found.");
           }
           Job encodeJob = composerService.encode(track, encodingProfile);
           if (!waitForStatus(encodeJob).isSuccess()) {
             throw new WorkflowOperationException(String.format(
                 "Audio extraction job for track %s did not complete successfully.", track.getURI()));
           }
           audioTrack = (Track) MediaPackageElementParser.getFromXml(encodeJob.getPayload());
         } catch (EncoderException | MediaPackageException e) {
           throw new WorkflowOperationException(
               String.format("Extracting audio for transcription failed for the track %s", track.getURI()), e);
         }
         try {
           Job transcriptionJob = service.startTranscription(mediaPackage.getIdentifier().toString(), audioTrack,
               language);
           // Wait for the jobs to return
           if (!waitForStatus(transcriptionJob).isSuccess()) {
             throw new WorkflowOperationException("Transcription job did not complete successfully.");
           }
           // Return OK means that the transcription job was created, but not finished yet
           logger.debug("External transcription job for media package '{}' was created.", mediaPackage.getIdentifier());
           // Only one job per media package
           // Results are empty, we should get a callback when transcription is done
           return createResult(Action.CONTINUE);
         } catch (TranscriptionServiceException e) {
           throw new WorkflowOperationException(e);
         }
       }
     } finally {
       // We do not need the audio file anymore, delete it...
       deleteTrack(audioTrack);
     }
     // If we are here, no audio tracks are found. Skip operation.
     logger.info("Media package {} does not contain audio stream to transcribe. Skip operation.",
         mediaPackage.getIdentifier());
     return createResult(Action.SKIP);
   }
 
   protected void deleteTrack(Track track) {
     if (track != null && track.getURI() != null) {
       try {
         workspace.delete(track.getURI());
       } catch (NotFoundException ex) {
         // do nothing
       } catch (IOException ex) {
         logger.warn("Unable to delete file {}", track.getURI());
       }
     }
   }
 
   @Reference(target = "(provider=microsoft.azure)")
   public void setTranscriptionService(TranscriptionService service) {
     this.service = service;
   }
 
   @Reference
   @Override
   public void setServiceRegistry(ServiceRegistry serviceRegistry) {
     super.setServiceRegistry(serviceRegistry);
   }
 
   @Reference
   public void setComposerService(ComposerService composerService) {
     this.composerService = composerService;
   }
 
   @Reference
   public void setWorkspace(Workspace workspace) {
     this.workspace = workspace;
   }
 }