/* 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 org.activiti.engine.impl.cmd;

import java.io.Serializable;

import org.activiti.engine.ActivitiIllegalArgumentException;
import org.activiti.engine.ActivitiObjectNotFoundException;
import org.activiti.engine.impl.interceptor.Command;
import org.activiti.engine.impl.interceptor.CommandContext;
import org.activiti.engine.impl.persistence.entity.ExecutionEntity;

/**
 * @author Marcus Klimstra
 */
public class AddIdentityLinkForProcessInstanceCmd implements Command<Void>, Serializable {

  private static final long serialVersionUID = 1L;

  protected String processInstanceId;

  protected String userId;

  protected String groupId;

  protected String type;

  public AddIdentityLinkForProcessInstanceCmd(String processInstanceId, String userId, String groupId, String type) {
    validateParams(processInstanceId, userId, groupId, type);
    this.processInstanceId = processInstanceId;
    this.userId = userId;
    this.groupId = groupId;
    this.type = type;
  }

  protected void validateParams(String processInstanceId, String userId, String groupId, String type) {

    if (processInstanceId == null) {
      throw new ActivitiIllegalArgumentException("processInstanceId is null");
    }

    if (type == null) {
      throw new ActivitiIllegalArgumentException("type is required when adding a new process instance identity link");
    }

    if (userId == null && groupId == null) {
      throw new ActivitiIllegalArgumentException("userId and groupId cannot both be null");
    }

  }

  public Void execute(CommandContext commandContext) {

    ExecutionEntity processInstance = commandContext.getExecutionEntityManager().findExecutionById(processInstanceId);

    if (processInstance == null) {
      throw new ActivitiObjectNotFoundException("Cannot find process instance with id " + processInstanceId, ExecutionEntity.class);
    }

    processInstance.addIdentityLink(userId, groupId, type);

    commandContext.getHistoryManager().createProcessInstanceIdentityLinkComment(processInstanceId, userId, groupId, type, true);

    return null;

  }

}