/*
    * 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.api;
  
  import static org.opencastproject.workflow.api.WorkflowOperationInstance.OperationState.INSTANTIATED;
  import static org.opencastproject.workflow.api.WorkflowOperationInstance.OperationState.PAUSED;
  import static org.opencastproject.workflow.api.WorkflowOperationInstance.OperationState.RETRY;
  import static org.opencastproject.workflow.api.WorkflowOperationInstance.OperationState.RUNNING;
  
  import org.opencastproject.mediapackage.MediaPackage;
  import org.opencastproject.mediapackage.MediaPackageException;
  import org.opencastproject.mediapackage.MediaPackageParser;
  import org.opencastproject.security.api.Organization;
  import org.opencastproject.security.api.User;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.Date;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.TreeMap;
  
  import javax.persistence.Access;
  import javax.persistence.AccessType;
  import javax.persistence.CascadeType;
  import javax.persistence.CollectionTable;
  import javax.persistence.Column;
  import javax.persistence.ElementCollection;
  import javax.persistence.Entity;
  import javax.persistence.FetchType;
  import javax.persistence.Id;
  import javax.persistence.Index;
  import javax.persistence.JoinColumn;
  import javax.persistence.Lob;
  import javax.persistence.MapKeyColumn;
  import javax.persistence.NamedQueries;
  import javax.persistence.NamedQuery;
  import javax.persistence.OneToMany;
  import javax.persistence.OrderColumn;
  import javax.persistence.Table;
  import javax.persistence.Temporal;
  import javax.persistence.TemporalType;
  import javax.persistence.Transient;
  import javax.xml.bind.annotation.adapters.XmlAdapter;
  
  /**
   * Entity object for storing workflows in persistence storage. Workflow ID is stored as primary key, DUBLIN_CORE field
   * is used to store serialized Dublin core and ACCESS_CONTROL field is used to store information about access control
   * rules.
   *
   */
  @Entity(name = "WorkflowInstance")
  @Access(AccessType.FIELD)
  @Table(name = "oc_workflow", indexes = {
          @Index(name = "IX_oc_workflow_mediapackage_id", columnList = ("mediapackage_id")),
          @Index(name = "IX_oc_workflow_series_id", columnList = ("series_id")), })
  @NamedQueries({
          @NamedQuery(
                  name = "Workflow.findAll",
                  query = "select w from WorkflowInstance w "
                      + "where w.organizationId=:organizationId order by w.dateCreated"
          ),
          @NamedQuery(
                  name = "Workflow.countLatest",
                  query = "SELECT COUNT(DISTINCT w.mediaPackageId) FROM WorkflowInstance w"
          ),
          @NamedQuery(
                  name = "Workflow.findAllOrganizationIndependent",
                  query = "select w from WorkflowInstance w"
          ),
          @NamedQuery(
                  name = "Workflow.workflowById",
                  query = "SELECT w FROM WorkflowInstance as w "
                      + "where w.workflowId=:workflowId and w.organizationId=:organizationId"
          ),
         @NamedQuery(
             name = "Workflow.workflowByIdOrganizationIndependent",
             query = "SELECT w FROM WorkflowInstance as w where w.workflowId=:workflowId"
         ),
         @NamedQuery(
                 name = "Workflow.getCount",
                 query = "select COUNT(w) from WorkflowInstance w where w.organizationId=:organizationId "
                         + "and (:state is null or w.state = :state) "
         ),
         @NamedQuery(
                 name = "Workflow.toCleanup",
                 query = "SELECT w FROM WorkflowInstance w where w.state = :state "
                 + "and w.dateCreated < :dateCreated and w.organizationId = :organizationId"
         ),
 
         // For media packages
         @NamedQuery(name = "Workflow.byMediaPackage",
             query = "SELECT w FROM WorkflowInstance w where "
                 + "w.mediaPackageId = :mediaPackageId and w.organizationId = :organizationId order by w.dateCreated"),
         @NamedQuery(name = "Workflow.countActiveByMediaPackage",
             query = "SELECT COUNT(w) FROM WorkflowInstance w where "
                 + "w.mediaPackageId = :mediaPackageId and w.organizationId = :organizationId and "
                 + "(w.state = :stateInstantiated or w.state = :statePaused or w.state = :stateRunning "
                 + "or w.state = :stateFailing)"),
         @NamedQuery(name = "Workflow.byMediaPackageAndActive",
             query = "SELECT w FROM WorkflowInstance w where "
                 + "w.mediaPackageId = :mediaPackageId and w.organizationId = :organizationId and "
                 + "(w.state = :stateInstantiated or w.state = :statePaused or w.state = :stateRunning "
                 + "or w.state = :stateFailing) order by w.dateCreated"),
 
         // For users
         @NamedQuery(name = "Workflow.countActiveByUser",
             query = "SELECT COUNT(w) FROM WorkflowInstance w where "
                 + "w.creatorName = :userId and w.organizationId = :organizationId and "
                 + "(w.state = :stateInstantiated or w.state = :statePaused or w.state = :stateRunning "
                 + "or w.state = :stateFailing)"),
 })
 public class WorkflowInstance {
 
   /** Workflow ID, primary key */
   /** The workflow id is the same as the related job id */
   /** It is set by the workflow service when creating the instance */
   @Id
   @Column(name = "id")
   private long workflowId;
 
   @Column(name = "state", length = 128)
   private WorkflowState state;
 
   @Column(name = "template")
   private String template;
 
   @Column(name = "title")
   private String title;
 
   @Column(name = "description")
   @Lob
   private String description;
 
   @Column(name = "creator_id")
   private String creatorName;
 
   @Column(name = "organization_id")  //NB: This column definition needs to match WorkflowIndexData!
   private String organizationId;
 
   @Column(name = "date_created")
   @Temporal(TemporalType.TIMESTAMP)
   private Date dateCreated = null;
 
   @Column(name = "date_completed")
   @Temporal(TemporalType.TIMESTAMP)
   private Date dateCompleted = null;
 
   @Lob
   @Column(name = "mediapackage", length = 16777215)
   private String mediaPackage;
 
   @Transient
   private MediaPackage mediaPackageObj;
 
   @OneToMany(
           mappedBy = "instance",
           cascade = CascadeType.ALL,
           orphanRemoval = true,
           fetch = FetchType.LAZY
   )
   @OrderColumn(name = "position")
   protected List<WorkflowOperationInstance> operations;
 
   @ElementCollection
   @CollectionTable(
           name = "oc_workflow_configuration",
           joinColumns = @JoinColumn(name = "workflow_id"),
           indexes = {
                 @Index(name = "IX_oc_workflow_configuration_workflow_id", columnList = ("workflow_id")),
           }
   )
   @MapKeyColumn(name = "configuration_key")
   @Lob
   @Column(name = "configuration_value")
   protected Map<String, String> configurations;
 
   @Column(name = "mediapackage_id", length = 128) //NB: This column definition needs to match WorkflowIndexData!
   protected String mediaPackageId;
 
   @Column(name = "series_id", length = 128)
   protected String seriesId;
 
   public enum WorkflowState {
     INSTANTIATED, RUNNING, STOPPED, PAUSED, SUCCEEDED, FAILED, FAILING;
 
     public boolean isTerminated() {
       switch (this) {
         case STOPPED:
         case SUCCEEDED:
         case FAILED:
           return true;
         default:
           return false;
       }
     }
     public static class Adapter extends XmlAdapter<String, WorkflowState> {
 
       @Override
       public String marshal(WorkflowState workflowState) {
         return workflowState == null ? null : workflowState.toString().toLowerCase();
       }
 
       @Override
       public WorkflowState unmarshal(String val) {
         return val == null ? null : WorkflowState.valueOf(val.toUpperCase());
       }
 
     }
   }
 
   /** Logging utilities */
   private static final Logger logger = LoggerFactory.getLogger(WorkflowInstance.class);
 
   /**
    * Default constructor without any import.
    */
   public WorkflowInstance() {
 
   }
 
   /**
    * Constructs a new workflow instance from the given definition, mediapackage, and optional parent workflow ID and
    * properties.
    */
   public WorkflowInstance(WorkflowDefinition def, MediaPackage mediaPackage, User creator,
           Organization organization, Map<String, String> configuration) {
     this.workflowId = -1; // this should be set by the workflow service once the workflow is persisted
     this.title = def.getTitle();
     this.template = def.getId();
     this.description = def.getDescription();
     this.creatorName = creator != null ? creator.getUsername() : null;
     this.organizationId = organization != null ? organization.getId() : null;
     this.state = WorkflowState.INSTANTIATED;
     this.dateCreated = new Date();
     this.mediaPackageObj = mediaPackage;
     this.mediaPackage = mediaPackage == null ? null : MediaPackageParser.getAsXml(mediaPackage);
     this.mediaPackageId = mediaPackage == null ? null : mediaPackage.getIdentifier().toString();
     this.seriesId = mediaPackage == null ? null : mediaPackage.getSeries();
 
     this.operations = new ArrayList<>();
     extend(def);
 
     this.configurations = new HashMap<>();
     if (configuration != null) {
       this.configurations.putAll(configuration);
     }
   }
 
   public WorkflowInstance(
           long id,
           WorkflowState state,
           String template,
           String title,
           String description,
           String creatorName,
           String organizationId,
           Date dateCreated,
           Date dateCompleted,
           MediaPackage mediaPackage,
           List<WorkflowOperationInstance> operations,
           Map<String, String> configurations,
           String mediaPackageId,
           String seriesId) {
     this.workflowId = id;
     this.state = state;
     this.template = template;
     this.title = title;
     this.description = description;
     this.creatorName = creatorName;
     this.organizationId = organizationId;
     this.dateCreated = dateCreated;
     this.dateCompleted = dateCompleted;
     this.mediaPackageObj = mediaPackage;
     this.mediaPackage = mediaPackage == null ? null : MediaPackageParser.getAsXml(mediaPackage);
     this.operations = operations;
     this.configurations = configurations;
     this.mediaPackageId = mediaPackageId;
     this.seriesId = seriesId;
   }
 
   public long getId() {
     return workflowId;
   }
 
   public void setId(long workflowId) {
     this.workflowId = workflowId;
   }
 
   public WorkflowState getState() {
     return state;
   }
 
   public void setState(WorkflowState state) {
     if (dateCompleted == null && state.isTerminated()) {
       dateCompleted = new Date();
     }
 
     this.state = state;
   }
 
   public String getTemplate() {
     return template;
   }
 
   public void setTemplate(String template) {
     this.template = template;
   }
 
   public String getTitle() {
     return title;
   }
 
   public void setTitle(String title) {
     this.title = title;
   }
 
   public String getDescription() {
     return description;
   }
 
   public void setDescription(String description) {
     this.description = description;
   }
 
   public String getCreatorName() {
     return creatorName;
   }
 
   public void setCreatorName(String creatorName) {
     this.creatorName = creatorName;
   }
 
   public String getOrganizationId() {
     return organizationId;
   }
 
   public void setOrganizationId(String organizationId) {
     this.organizationId = organizationId;
   }
 
   public Date getDateCreated() {
     return dateCreated;
   }
 
   public void setDateCreated(Date dateCreated) {
     this.dateCreated = dateCreated;
   }
 
   public Date getDateCompleted() {
     return dateCompleted;
   }
 
   public void setDateCompleted(Date dateCompleted) {
     this.dateCompleted = dateCompleted;
   }
 
   public MediaPackage getMediaPackage()  {
     try {
       if (mediaPackageObj != null) {
         return mediaPackageObj;
       }
       if (mediaPackage != null) {
         mediaPackageObj = MediaPackageParser.getFromXml(mediaPackage);
         return mediaPackageObj;
       }
     } catch (MediaPackageException e) {
       logger.error("Error parsing media package in workflow instance", e);
     }
     return null;
   }
 
   public void setMediaPackage(MediaPackage mediaPackage) {
     this.mediaPackageObj = mediaPackage;
     this.mediaPackage = mediaPackage == null ? null : MediaPackageParser.getAsXml(mediaPackage);
     this.mediaPackageId = mediaPackage == null ? null : mediaPackage.getIdentifier().toString();
     this.seriesId = mediaPackage == null ? null : mediaPackage.getSeries();
   }
 
   public boolean isActive() {
     return !getState().isTerminated();
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.WorkflowInstance#getOperations()
    */
   public List<WorkflowOperationInstance> getOperations() {
     if (operations == null) {
       operations = new ArrayList<>();
     }
     return operations;
   }
 
   /**
    * Sets the workflow operations on this workflow instance
    *
    * @param workflowOperationInstanceList List of operations to set.
    */
   public final void setOperations(List<WorkflowOperationInstance> workflowOperationInstanceList) {
     for (var workflowOperationInstance : workflowOperationInstanceList) {
       workflowOperationInstance.setWorkflowInstance(this);
     }
     this.operations = workflowOperationInstanceList;
   }
 
   /**
    * Returns the workflow operation that is currently active or next to be executed.
    *
    * @return the current operation
    */
   public WorkflowOperationInstance getCurrentOperation() {
     logger.debug("operations: {}", operations);
     if (operations == null) {
       return null;
     }
 
     // Find first operation to work on. This should be the first one in state RUNNING; PAUSED, INSTANTIATED or RETRY.
     // If one is active right now, it should be RUNNING or PAUSED.
     // If none is active right now, it should be INSTANTIATED or RETRY as this should be the next one being run.
     var currentStates = List.of(RUNNING, PAUSED, RETRY, INSTANTIATED);
     for (var operation : operations) {
       if (currentStates.contains(operation.getState())) {
         logger.debug("current operation: {}", operation);
         return operation;
       }
     }
     return null;
   }
 
   public Map<String, String> getConfigurations() {
     if (configurations == null) {
       return Collections.emptyMap();
     }
     return configurations;
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.Configurable#getConfiguration(java.lang.String)
    */
   public String getConfiguration(String key) {
     if (key == null || configurations == null) {
       return null;
     }
     return configurations.get(key);
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.Configurable#getConfigurationKeys()
    */
   public Set<String> getConfigurationKeys() {
     if (configurations == null) {
       return Collections.emptySet();
     }
     return configurations.keySet();
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.Configurable#removeConfiguration(java.lang.String)
    */
   public void removeConfiguration(String key) {
     if (key == null || configurations == null) {
       return;
     }
     configurations.remove(key);
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.workflow.api.Configurable#setConfiguration(java.lang.String, java.lang.String)
    */
   public void setConfiguration(String key, String value) {
     if (key == null) {
       return;
     }
     if (configurations == null) {
       configurations = new TreeMap<>();
     }
 
     // Adjust already existing values
     configurations.put(key, value);
   }
 
   @Override
   public int hashCode() {
     return Long.valueOf(workflowId).hashCode();
   }
 
   @Override
   public boolean equals(Object obj) {
     if (obj instanceof WorkflowInstance) {
       WorkflowInstance other = (WorkflowInstance) obj;
       return workflowId == other.getId();
     }
     return false;
   }
 
   @Override
   public String toString() {
     return "Workflow {" + workflowId + "}";
   }
 
 
   public void extend(WorkflowDefinition workflowDefinition) {
     for (var operation : workflowDefinition.getOperations()) {
       var operationInstance = new WorkflowOperationInstance(operation);
       operationInstance.setWorkflowInstance(this);
       operations.add(operationInstance);
     }
     setTemplate(workflowDefinition.getId());
   }
 
   public void insert(WorkflowDefinition workflowDefinition, WorkflowOperationInstance after) {
     var index = operations.indexOf(after) + 1;
     for (var operation : workflowDefinition.getOperations()) {
       var operationInstance = new WorkflowOperationInstance(operation);
       operationInstance.setWorkflowInstance(this);
       operations.add(index, operationInstance);
       index++;
     }
   }
 }