/*
    * 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.impl;
  
  import static org.opencastproject.util.data.Option.some;
  
  import org.opencastproject.kernel.scanner.AbstractScanner;
  import org.opencastproject.security.api.Organization;
  import org.opencastproject.security.api.OrganizationDirectoryService;
  import org.opencastproject.security.api.SecurityService;
  import org.opencastproject.security.api.UnauthorizedException;
  import org.opencastproject.serviceregistry.api.ServiceRegistry;
  import org.opencastproject.serviceregistry.api.ServiceRegistryException;
  import org.opencastproject.util.NeedleEye;
  import org.opencastproject.workflow.api.WorkflowDatabaseException;
  import org.opencastproject.workflow.api.WorkflowInstance;
  import org.opencastproject.workflow.api.WorkflowService;
  
  import org.apache.commons.lang3.BooleanUtils;
  import org.apache.commons.lang3.StringUtils;
  import org.osgi.service.cm.ConfigurationException;
  import org.osgi.service.cm.ManagedService;
  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.Deactivate;
  import org.osgi.service.component.annotations.Reference;
  import org.quartz.JobDetail;
  import org.quartz.JobExecutionContext;
  import org.quartz.impl.StdSchedulerFactory;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.Dictionary;
  import java.util.concurrent.locks.ReentrantLock;
  
  @Component(
      immediate = true,
      service = ManagedService.class,
      property = {
          "service.description=Workflow Cleanup Scanner Service"
      }
  )
  public class WorkflowCleanupScanner extends AbstractWorkflowBufferScanner implements ManagedService {
    private static final String SCANNER_NAME = "Workflow Cleanup Scanner";
  
    /** The logging facility */
    private static final Logger logger = LoggerFactory.getLogger(WorkflowCleanupScanner.class);
  
    private static final String JOB_NAME = "mh-workflow-cleanup-job";
    private static final String JOB_GROUP = "mh-workflow-cleanup-job-group";
    private static final String TRIGGER_NAME = "mh-workflow-cleanup-trigger";
    private static final String TRIGGER_GROUP = "mh-workflow-cleanup-trigger-group";
  
    private static final String PARAM_KEY_BUFFER_SUCCEEDED = "buffer.succeeded";
    private static final String PARAM_KEY_BUFFER_FAILED = "buffer.failed";
    private static final String PARAM_KEY_BUFFER_STOPPED = "buffer.stopped";
    private static final String PARAM_KEY_BUFFER_PARENTLESS = "buffer.parentless";
  
    /** Buffer of successful jobs in days */
    protected static int bufferForSuccessfulJobs = -1;
  
    /** Buffer of failed jobs in days */
    protected static int bufferForFailedJobs = -1;
  
    /** Buffer of failed jobs in days */
    protected static int bufferForStoppedJobs = -1;
  
    /** Buffer of parentless jobs in days */
    protected static int bufferForParentlessJobs = -1;
  
    // Lock to prevent concurrent cleanups
    private static final ReentrantLock lock = new ReentrantLock();
  
    public WorkflowCleanupScanner() {
      try {
        quartz = new StdSchedulerFactory().getScheduler();
        quartz.start();
        // create and set the job. To actually run it call schedule(..)
        final JobDetail job = new JobDetail(getJobName(), getJobGroup(), Runner.class);
       job.setDurability(false);
       job.setVolatility(true);
       job.getJobDataMap().put(JOB_PARAM_PARENT, this);
       quartz.addJob(job, true);
     } catch (org.quartz.SchedulerException e) {
       throw new RuntimeException(e);
     }
   }
 
   @Activate
   @Override
   public void activate(ComponentContext cc) {
     super.activate(cc);
   }
 
   @Deactivate
   @Override
   public void deactivate() {
     super.deactivate();
   }
 
   @Override
   public String getJobGroup() {
     return JOB_GROUP;
   }
 
   @Override
   public String getJobName() {
     return JOB_NAME;
   }
 
   @Override
   public String getTriggerGroupName() {
     return TRIGGER_GROUP;
   }
 
   @Override
   public String getTriggerName() {
     return TRIGGER_NAME;
   }
 
   @Override
   public void updated(@SuppressWarnings("rawtypes") Dictionary properties) throws ConfigurationException {
     boolean enabled = false;
     String cronExpression;
     unschedule();
 
     if (properties != null) {
       logger.debug("Updating configuration...");
 
       enabled = BooleanUtils.toBoolean((String) properties.get(AbstractScanner.PARAM_KEY_ENABLED));
       setEnabled(enabled);
       logger.debug("enabled = {}", enabled);
 
       cronExpression = (String) properties.get(AbstractScanner.PARAM_KEY_CRON_EXPR);
       if (StringUtils.isBlank(cronExpression)) {
         throw new ConfigurationException(AbstractScanner.PARAM_KEY_CRON_EXPR, "Cron expression must be valid");
       }
       setCronExpression(cronExpression);
       logger.debug("cronExpression = {}", cronExpression);
 
       try {
         bufferForSuccessfulJobs = Integer.valueOf((String) properties.get(PARAM_KEY_BUFFER_SUCCEEDED));
       } catch (NumberFormatException e) {
         throw new ConfigurationException(PARAM_KEY_BUFFER_SUCCEEDED, "Buffer must be a valid integer", e);
       }
       logger.debug("bufferForSuccessfulJobs = {}", bufferForSuccessfulJobs);
 
       try {
         bufferForFailedJobs = Integer.valueOf((String) properties.get(PARAM_KEY_BUFFER_FAILED));
       } catch (NumberFormatException e) {
         throw new ConfigurationException(PARAM_KEY_BUFFER_FAILED, "Buffer must be a valid integer", e);
       }
       logger.debug("bufferForFailedJobs = {}", bufferForFailedJobs);
 
       try {
         bufferForStoppedJobs = Integer.valueOf((String) properties.get(PARAM_KEY_BUFFER_STOPPED));
       } catch (NumberFormatException e) {
         throw new ConfigurationException(PARAM_KEY_BUFFER_STOPPED, "Buffer must be a valid integer", e);
       }
       logger.debug("bufferForStoppedJobs = {}", bufferForStoppedJobs);
 
       try {
         bufferForParentlessJobs = Integer.valueOf((String) properties.get(PARAM_KEY_BUFFER_PARENTLESS));
       } catch (NumberFormatException e) {
         throw new ConfigurationException(PARAM_KEY_BUFFER_PARENTLESS, "Buffer must be a valid integer", e);
       }
       logger.debug("bufferForParentlessJobs = {}", bufferForParentlessJobs);
     }
 
     schedule();
   }
 
   @Override
   public void scan() {
     if (lock.isLocked()) {
       logger.info("Skipping workflow scan since a previous scan is still active");
       return;
     }
     try {
       lock.lock();
       if (bufferForFailedJobs > 0) {
         try {
           getWorkflowService().cleanupWorkflowInstances(bufferForFailedJobs, WorkflowInstance.WorkflowState.FAILED);
         } catch (WorkflowDatabaseException e) {
           logger.error("Unable to cleanup failed jobs:", e);
         } catch (UnauthorizedException e) {
           logger.error("Workflow cleanup job doesn't have right to delete jobs!");
           throw new IllegalStateException(e);
         }
       }
 
       if (bufferForSuccessfulJobs > 0) {
         try {
           getWorkflowService().cleanupWorkflowInstances(bufferForSuccessfulJobs, WorkflowInstance.WorkflowState.SUCCEEDED);
         } catch (WorkflowDatabaseException e) {
           logger.error("Unable to cleanup successful jobs:", e);
         } catch (UnauthorizedException e) {
           logger.error("Workflow cleanup job doesn't have right to delete jobs!");
           throw new IllegalStateException(e);
         }
       }
 
       if (bufferForStoppedJobs > 0) {
         try {
           getWorkflowService().cleanupWorkflowInstances(bufferForStoppedJobs, WorkflowInstance.WorkflowState.STOPPED);
         } catch (WorkflowDatabaseException e) {
           logger.error("Unable to cleanup stopped jobs:", e);
         } catch (UnauthorizedException e) {
           logger.error("Workflow cleanup job doesn't have right to delete jobs!");
           throw new IllegalStateException(e);
         }
       }
 
       if (bufferForParentlessJobs > 0) {
         try {
           getServiceRegistry().removeParentlessJobs(bufferForParentlessJobs);
         } catch (ServiceRegistryException e) {
           logger.error("There was an error while removing parentless jobs: {}", e.getMessage());
         }
       }
     } finally {
       lock.unlock();
     }
   }
 
   @Override
   public String getScannerName() {
     return SCANNER_NAME;
   }
 
   /** Quartz job to which cleans up the workflow instances */
   public static class Runner extends TypedQuartzJob<AbstractScanner> {
     private static final NeedleEye eye = new NeedleEye();
 
     public Runner() {
       super(some(eye));
     }
 
     @Override
     protected void execute(final AbstractScanner parameters, JobExecutionContext ctx) {
       logger.debug("Starting " + parameters.getScannerName() + " job.");
 
       // iterate all organizations
       for (final Organization org : parameters.getOrganizationDirectoryService().getOrganizations()) {
         // set the organization on the current thread
         parameters.getAdminContextFor(org.getId()).runInContext(parameters::scan);
       }
 
       logger.info("Finished " + parameters.getScannerName() + " job.");
     }
   }
 
   @Reference
   @Override
   public void bindWorkflowService(WorkflowService workflowService) {
     super.bindWorkflowService(workflowService);
   }
 
   @Reference
   @Override
   public void bindServiceRegistry(ServiceRegistry serviceRegistry) {
     super.bindServiceRegistry(serviceRegistry);
   }
 
   @Reference
   @Override
   public void bindOrganizationDirectoryService(OrganizationDirectoryService organizationDirectoryService) {
     super.bindOrganizationDirectoryService(organizationDirectoryService);
   }
 
   @Reference
   @Override
   public void bindSecurityService(SecurityService securityService) {
     super.bindSecurityService(securityService);
   }
 
 }