/*
    * 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.execute.operation.handler;
  
  import org.opencastproject.execute.api.ExecuteException;
  import org.opencastproject.execute.api.ExecuteService;
  import org.opencastproject.inspection.api.MediaInspectionException;
  import org.opencastproject.inspection.api.MediaInspectionService;
  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.MediaPackageElementFlavor;
  import org.opencastproject.mediapackage.MediaPackageElementParser;
  import org.opencastproject.mediapackage.MediaPackageException;
  import org.opencastproject.mediapackage.Track;
  import org.opencastproject.mediapackage.selector.SimpleElementSelector;
  import org.opencastproject.serviceregistry.api.ServiceRegistry;
  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.workflow.api.WorkflowOperationResultImpl;
  import org.opencastproject.workspace.api.Workspace;
  
  import org.apache.commons.lang3.StringUtils;
  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.File;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.net.URI;
  import java.nio.charset.StandardCharsets;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.Properties;
  import java.util.Set;
  
  /**
   * Runs an operation multiple times with each MediaPackageElement matching the characteristics
   */
  @Component(
      immediate = true,
      service = WorkflowOperationHandler.class,
      property = {
          "service.description=Execute Many Workflow Operation Handler",
          "workflow.operation=execute-many"
      }
  )
  public class ExecuteManyWorkflowOperationHandler extends AbstractWorkflowOperationHandler {
  
    /** The logging facility */
    private static final Logger logger = LoggerFactory.getLogger(ExecuteManyWorkflowOperationHandler.class);
  
    /** Property containing the command to run */
    public static final String EXEC_PROPERTY = "exec";
  
    /** Property containing the list of command parameters */
    public static final String PARAMS_PROPERTY = "params";
  
    /** Property containingn an approximation of the load imposed by running this operation */
    public static final String LOAD_PROPERTY = "load";
  
    /** Property containing the "flavor" that a mediapackage elements must have in order to be used as input arguments */
    public static final String SOURCE_FLAVOR_PROPERTY = "source-flavor";
  
    /** Property containing the filename of the elements created by this operation */
    public static final String OUTPUT_FILENAME_PROPERTY = "output-filename";
 
   /** Property containing the expected type of the element generated by this operation */
   public static final String EXPECTED_TYPE_PROPERTY = "expected-type";
 
   /**
    * Property containing the tags that must exist on a mediapackage element for the element to be used as an input
    * arguments
    */
   public static final String SOURCE_TAGS_PROPERTY = "source-tags";
 
   /** Property defining whether the track is required to contain or not contain an audio stream to be used an input */
   public static final String SOURCE_AUDIO_PROPERTY = "source-audio";
 
   /** Property defining whether the track is required to contain or not contain a video stream to be used an input */
   public static final String SOURCE_VIDEO_PROPERTY = "source-video";
 
   /** Property defining whether the track is required to contain or not contain a subtitle stream to be used an input */
   public static final String SOURCE_SUBTITLE_PROPERTY = "source-subtitle";
 
   /** Property containing the flavor that the resulting mediapackage elements will be assigned */
   public static final String TARGET_FLAVOR_PROPERTY = "target-flavor";
 
   /** Property containing the tags that the resulting mediapackage elements will be assigned */
   public static final String TARGET_TAGS_PROPERTY = "target-tags";
 
   /** Property to control whether command output will be used to set workflow properties */
   public static final String SET_WF_PROPS_PROPERTY = "set-workflow-properties";
 
   /** The text analyzer */
   protected ExecuteService executeService;
 
   /** Reference to the media inspection service */
   private MediaInspectionService inspectionService = null;
 
   /** The workspace service */
   protected Workspace workspace;
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.WorkflowOperationHandler#start(org.opencastproject.workflow.api.WorkflowInstance,
    *      JobContext)
    */
   @Override
   public WorkflowOperationResult start(WorkflowInstance workflowInstance, JobContext context)
           throws WorkflowOperationException {
 
     MediaPackage mediaPackage = workflowInstance.getMediaPackage();
     WorkflowOperationInstance operation = workflowInstance.getCurrentOperation();
 
     logger.debug("Running execute workflow operation with ID {}", operation.getId());
 
     // Get operation parameters
     String exec = StringUtils.trimToNull(operation.getConfiguration(EXEC_PROPERTY));
     String params = StringUtils.trimToNull(operation.getConfiguration(PARAMS_PROPERTY));
     float load = 1.0f;
     String loadPropertyStr = StringUtils.trimToEmpty(operation.getConfiguration(LOAD_PROPERTY));
     if (StringUtils.isNotBlank(loadPropertyStr)) {
       try {
         load = Float.parseFloat(loadPropertyStr);
       } catch (NumberFormatException e) {
         String description = StringUtils.trimToEmpty(operation.getDescription());
         logger.warn("Ignoring invalid load value '{}' on execute operation with description '{}'", loadPropertyStr,
                 description);
       }
     }
     ConfiguredTagsAndFlavors tagsAndFlavors = getTagsAndFlavors(workflowInstance,
         Configuration.many, Configuration.many, Configuration.many, Configuration.many);
     List<MediaPackageElementFlavor> sourceFlavor = tagsAndFlavors.getSrcFlavors();
     List<String> sourceTagList = tagsAndFlavors.getSrcTags();
     String sourceAudio = StringUtils.trimToNull(operation.getConfiguration(SOURCE_AUDIO_PROPERTY));
     String sourceVideo = StringUtils.trimToNull(operation.getConfiguration(SOURCE_VIDEO_PROPERTY));
     String sourceSubtitle = StringUtils.trimToNull(operation.getConfiguration(SOURCE_SUBTITLE_PROPERTY));
     List<MediaPackageElementFlavor> targetFlavorList = tagsAndFlavors.getTargetFlavors();
     List<String> targetTags = tagsAndFlavors.getTargetTags();
     String outputFilename = StringUtils.trimToNull(operation.getConfiguration(OUTPUT_FILENAME_PROPERTY));
     String expectedTypeStr = StringUtils.trimToNull(operation.getConfiguration(EXPECTED_TYPE_PROPERTY));
 
     boolean setWfProps = Boolean.valueOf(StringUtils.trimToNull(operation.getConfiguration(SET_WF_PROPS_PROPERTY)));
 
     // Unmarshall target flavor
     MediaPackageElementFlavor targetFlavor = null;
     if (!targetFlavorList.isEmpty())
       targetFlavor = targetFlavorList.get(0);
 
     // Unmarshall expected mediapackage element type
     MediaPackageElement.Type expectedType = null;
     if (expectedTypeStr != null) {
       for (MediaPackageElement.Type type : MediaPackageElement.Type.values())
         if (type.toString().equalsIgnoreCase(expectedTypeStr)) {
           expectedType = type;
           break;
         }
 
       if (expectedType == null)
         throw new WorkflowOperationException("'" + expectedTypeStr + "' is not a valid element type");
     }
 
     // Select the tracks based on source flavors and tags
     Set<MediaPackageElement> inputSet = new HashSet<>();
 
     SimpleElementSelector elementSelector = new SimpleElementSelector();
     for (MediaPackageElementFlavor flavor : sourceFlavor) {
       elementSelector.addFlavor(flavor);
     }
     for (String tag : sourceTagList) {
       elementSelector.addTag(tag);
     }
 
     for (MediaPackageElement element : elementSelector.select(mediaPackage, true)) {
       // Check for audio or video streams in the track, if specified
       if ((element instanceof Track) && (sourceAudio != null)
           && (Boolean.parseBoolean(sourceAudio) != ((Track) element).hasAudio())) {
         continue;
       }
 
       if ((element instanceof Track) && (sourceVideo != null)
           && (Boolean.parseBoolean(sourceVideo) != ((Track) element).hasVideo())) {
         continue;
       }
 
       if ((element instanceof Track) && (sourceSubtitle != null)
           && (Boolean.parseBoolean(sourceSubtitle) != ((Track) element).hasSubtitle())) {
         continue;
       }
 
       inputSet.add(element);
     }
 
     if (inputSet.size() == 0) {
       logger.warn("Mediapackage {} has no suitable elements to execute the command {} based on tags {}, flavor {}, sourceAudio {}, sourceVideo {}, sourceSubtitle {}",
               mediaPackage, exec, sourceTagList, sourceFlavor, sourceAudio, sourceVideo, sourceSubtitle);
       return createResult(mediaPackage, Action.CONTINUE);
     }
 
     MediaPackageElement[] inputElements = inputSet.toArray(new MediaPackageElement[inputSet.size()]);
 
     Map<String, String> wfProps = new HashMap<>();
 
     try {
       Job[] jobs = new Job[inputElements.length];
       MediaPackageElement[] resultElements = new MediaPackageElement[inputElements.length];
       long totalTimeInQueue = 0;
 
       for (int i = 0; i < inputElements.length; i++)
         jobs[i] = executeService.execute(exec, params, inputElements[i], outputFilename, expectedType, load);
 
       // Wait for all jobs to be finished
       if (!waitForStatus(jobs).isSuccess())
         throw new WorkflowOperationException("Execute operation failed");
 
       // Find which output elements are tracks and inspect them
       HashMap<Integer, Job> jobMap = new HashMap<>();
       for (int i = 0; i < jobs.length; i++) {
         // Add this job's queue time to the total
         totalTimeInQueue += jobs[i].getQueueTime();
         if (StringUtils.trimToNull(jobs[i].getPayload()) != null) {
           resultElements[i] = MediaPackageElementParser.getFromXml(jobs[i].getPayload());
           if (resultElements[i].getElementType() == MediaPackageElement.Type.Track) {
             jobMap.put(i, inspectionService.inspect(resultElements[i].getURI()));
           }
         } else
           resultElements[i] = inputElements[i];
       }
 
       if (jobMap.size() > 0) {
         if (!waitForStatus(jobMap.values().toArray(new Job[jobMap.size()])).isSuccess())
           throw new WorkflowOperationException("Execute operation failed in track inspection");
 
         for (Entry<Integer, Job> entry : jobMap.entrySet()) {
           // Add this job's queue time to the total
           totalTimeInQueue += entry.getValue().getQueueTime();
           resultElements[entry.getKey()] = MediaPackageElementParser.getFromXml(entry.getValue().getPayload());
         }
       }
 
       for (int i = 0; i < resultElements.length; i++) {
         if (resultElements[i] != inputElements[i]) {
 
           if (setWfProps) {
             // The job payload is a file with set of properties for the workflow
             final Properties properties = new Properties();
             File propertiesFile = workspace.get(resultElements[i].getURI());
             try (InputStreamReader reader = new InputStreamReader(new FileInputStream(propertiesFile), StandardCharsets.UTF_8)) {
               properties.load(reader);
             }
             logger.debug("Loaded {} properties from {}", properties.size(), propertiesFile);
             workspace.deleteFromCollection(ExecuteService.COLLECTION, propertiesFile.getName());
 
             // Add the properties to the wfProps
             wfProps.putAll((Map) properties);
 
           } else {
             // The job payload is a new element for the MediaPackage
             // Store new element to mediaPackage
             mediaPackage.addDerived(resultElements[i], inputElements[i]);
             // Store new element to mediaPackage
             URI uri = workspace.moveTo(resultElements[i].getURI(), mediaPackage.getIdentifier().toString(),
                   resultElements[i].getIdentifier(), outputFilename);
 
             resultElements[i].setURI(uri);
 
             // Set new flavor
             if (targetFlavor != null) {
               String targetFlavorType = targetFlavor.getType();
               String targetFlavorSubtype = targetFlavor.getSubtype();
 
               if (MediaPackageElementFlavor.WILDCARD.equals(targetFlavorType)) {
                 targetFlavorType = inputElements[i].getFlavor().getType();
               }
 
               if (MediaPackageElementFlavor.WILDCARD.equals(targetFlavorSubtype)) {
                 targetFlavorSubtype = inputElements[i].getFlavor().getSubtype();
               }
 
               String resolvedTargetFlavorStr =
                   targetFlavorType + MediaPackageElementFlavor.SEPARATOR + targetFlavorSubtype;
               resultElements[i].setFlavor(MediaPackageElementFlavor.parseFlavor(resolvedTargetFlavorStr));
             }
           }
         }
 
         // Set new tags
         if (targetTags != null) {
           // Assume the tags starting with "-" means we want to eliminate such tags form the result element
           for (String tag : targetTags) {
             if (tag.startsWith("-"))
               // We remove the tag resulting from stripping all the '-' characters at the beginning of the tag
               resultElements[i].removeTag(tag.replaceAll("^-+", ""));
             else
               resultElements[i].addTag(tag);
           }
         }
       }
 
       WorkflowOperationResult result = createResult(mediaPackage, wfProps, Action.CONTINUE, totalTimeInQueue);
       logger.debug("Execute operation {} completed", operation.getId());
 
       return result;
 
     } catch (ExecuteException e) {
       throw new WorkflowOperationException(e);
     } catch (MediaPackageException e) {
       throw new WorkflowOperationException("Some result element couldn't be serialized", e);
     } catch (NotFoundException e) {
       throw new WorkflowOperationException("Could not find mediapackage", e);
     } catch (IOException e) {
       throw new WorkflowOperationException("Error unmarshalling a result mediapackage element", e);
     } catch (MediaInspectionException e) {
       throw new WorkflowOperationException("Error inspecting one of the created tracks", e);
     }
 
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.WorkflowOperationHandler#skip(org.opencastproject.workflow.api.WorkflowInstance,
    *      JobContext)
    */
   @Override
   public WorkflowOperationResult skip(WorkflowInstance workflowInstance, JobContext context)
           throws WorkflowOperationException {
     return new WorkflowOperationResultImpl(workflowInstance.getMediaPackage(), null, Action.SKIP, 0);
   }
 
   @Override
   public String getId() {
     return "execute";
   }
 
   @Override
   public String getDescription() {
     return "Executes command line workflow operations in workers";
   }
 
   @Override
   public void destroy(WorkflowInstance workflowInstance, JobContext context) throws WorkflowOperationException {
     // Do nothing (nothing to clean up, the command line program should do this itself)
   }
 
   /**
    * Sets the service
    *
    * @param service
    */
   @Reference
   public void setExecuteService(ExecuteService service) {
     executeService = service;
   }
 
   /**
    * Sets a reference to the workspace service.
    *
    * @param workspace
    */
   @Reference
   public void setWorkspace(Workspace workspace) {
     this.workspace = workspace;
   }
 
   /**
    * Sets the media inspection service
    *
    * @param mediaInspectionService
    *          an instance of the media inspection service
    */
   @Reference
   protected void setMediaInspectionService(MediaInspectionService mediaInspectionService) {
     inspectionService = mediaInspectionService;
   }
 
   @Reference
   @Override
   public void setServiceRegistry(ServiceRegistry serviceRegistry) {
     super.setServiceRegistry(serviceRegistry);
   }
 
 }