/**
 * Copyright 2014 Tampere University of Technology, Pori Department
 * 
 * Licensed under the Apache 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://www.apache.org/licenses/LICENSE-2.0
 * 
 * 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 service.tut.pori.contentanalysis;

import java.util.Map;

import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlElementRef;
import javax.xml.bind.annotation.XmlRootElement;

import org.apache.commons.lang3.ArrayUtils;

import service.tut.pori.contentanalysis.AsyncTask.TaskType;
import core.tut.pori.http.ResponseData;
import core.tut.pori.users.UserIdentity;


/**
 * The base class for task details (task workload). Contains basic members and functionality needed for task submission.
 * 
 * Note: remember to define \@XmlRootElement(name=ELEMENT_NAME) for your inherited class
 * 
 * <h2>Optional Elements</h2>
 * <ul>
 *  <li>{@value core.tut.pori.users.Definitions#ELEMENT_USER_ID}, missing if task is generated by the system, or the task is anonymous.</li>
 *  <li>{@value service.tut.pori.contentanalysis.Definitions#ELEMENT_TASK_PARAMETERS}. The parameters depend on the task in question. If the element is missing the back-ends should run back-end specific default operation. </li>
 * </ul>
 * 
 * @see service.tut.pori.contentanalysis.BackendStatusList
 */
@XmlAccessorType(XmlAccessType.NONE)
public abstract class AbstractTaskDetails extends ResponseData{
  @XmlElement(name = Definitions.ELEMENT_BACKEND_ID)
  private Integer _backendId = null;
  private String _callbackUri = null;
  @XmlElement(name = Definitions.ELEMENT_TASK_ID)
  private Long _taskId = null;
  @XmlElement(name = Definitions.ELEMENT_TASK_TYPE)
  private TaskType _taskType = null;
  private UserIdentity _userId = null;
  @XmlElement(name = Definitions.ELEMENT_BACKEND_STATUS_LIST)
  private BackendStatusList _backends = null; // an optional list of back-ends participating in this task
  private Map<String, String> _metadata = null;
  
  /**
   * 
   * @return the value of user identity
   * @see #getUserId()
   */
  @XmlElement(name = core.tut.pori.users.Definitions.ELEMENT_USER_ID)
  public Long getUserIdValue(){
    return (_userId == null ? null : _userId.getUserId());
  }
  
  /**
   * for serialization
   * @param value
   * @see #setUserId(UserIdentity)
   */
  @SuppressWarnings("unused")
  private void setUserIdValue(Long value){
    if(value != null){
      _userId = new UserIdentity(value);
    }
  }

  /**
   * 
   * @return user identity
   * @see #setUserId(UserIdentity)
   */
  public UserIdentity getUserId() {
    return _userId;
  }

  /**
   * 
   * @param userId
   * @see #getUserId()
   */
  public void setUserId(UserIdentity userId) {
    _userId = userId;
  }

  /**
   * 
   * @param type
   * @see #getTaskType()
   */
  public void setTaskType(TaskType type){
    _taskType = type;
  }

  /**
   * 
   * @return task type
   * @see #setTaskType(service.tut.pori.contentanalysis.AsyncTask.TaskType)
   */
  public TaskType getTaskType() {
    return _taskType;
  }

  /**
   * 
   * @return back-end id of the first back-end in the status list
   * @see #getBackendId()
   */
  public Integer getBackendId() {
    return _backendId;
  }

  /**
   * @param backendId
   * @see #getBackendId()
   */
  public void setBackendId(Integer backendId) {
    _backendId = backendId;
  }

  /**
   * 
   * @return task id
   * @see #setTaskId(Long)
   */
  public Long getTaskId() {
    return _taskId;
  }

  /**
   * 
   * @param taskId
   * @see #getTaskId()
   */
  public void setTaskId(Long taskId){
    _taskId = taskId;     
  }

  /**
   * 
   * @return callback uri
   * @see #setCallbackUri(String)
   */
  @XmlElement(name = Definitions.ELEMENT_CALLBACK_URI)
  public String getCallbackUri() {
    return _callbackUri;
  }

  /**
   * Can be used to override the default, generated call back uri
   * 
   * @param callbackUri
   * @see #getCallbackUri()
   */
  public void setCallbackUri(String callbackUri) {
    _callbackUri = callbackUri;
  }

  /**
   * Default data groups: {@value service.tut.pori.contentanalysis.Definitions#DATA_GROUP_BACKEND_STATUS}
   * 
   * @return the backends
   * @see #setBackends(BackendStatusList)
   */
  public BackendStatusList getBackends() {
    return _backends;
  }

  /**
   * @param backends the backends to set
   * @see #getBackends()
   */
  public void setBackends(BackendStatusList backends) {
    _backends = backends;
  }
  
  /**
   * 
   * @param status
   * @see #getBackends()
   */
  public void setBackend(BackendStatus status) {
    if(_backends == null){
      _backends = new BackendStatusList();
    }
    _backends.setBackendStatus(status);
  }

  /**
   * @return the metadata
   * @see #setMetadata(Map)
   */
  public Map<String, String> getMetadata() {
    return _metadata;
  }

  /**
   * @param metadata the metadata to set
   * @see #getMetadata()
   */
  public void setMetadata(Map<String, String> metadata) {
    _metadata = metadata;
  }

  @Override
  public Class<?>[] getDataClasses() {
    Class<?>[] classes = super.getDataClasses();
    TaskParameters params = getTaskParameters();
    if(params != null){
      classes = ArrayUtils.add(classes, params.getClass());
    }
    return classes;
  }

  /**
   * @return the parameters
   * @see #setTaskParameters(TaskParameters)
   */
  @XmlElementRef
  public abstract TaskParameters getTaskParameters();

  /**
   * @param parameters the parameters to set
   * @see #getTaskParameters()
   */
  public abstract void setTaskParameters(TaskParameters parameters);
  
  /**
   * Abstract base class for optional task parameters.
   * 
   * The class should have no-args constructor for database serialization.
   *
   */
  @XmlRootElement(name = Definitions.ELEMENT_TASK_PARAMETERS)
  @XmlAccessorType(XmlAccessType.NONE)
  public static abstract class TaskParameters {
    /**
     * initialize the the parameters from the given metadata map
     * 
     * @param metadata
     * @throws IllegalArgumentException on bad values
     */
    public abstract void initialize(Map<String, String> metadata) throws IllegalArgumentException;

    /**
     * 
     * @return this object converted to metadata map or null if no content
     */
    public abstract Map<String, String> toMetadata();
    
    /**
     * For database serialization
     */
    public TaskParameters(){
      // nothing needed
    }
  } // class TaskParameters
}