ItemHistory::getAction

public function getAction(): ?string
{
	if(empty(parent::getAction()))
	{
		if($this->getTaskId() > 0)
		{
			return static::ACTION_TASK_COMPLETE;
		}
		if($this->item)
		{
			if($this->item->getId() > 0)
			{
				$isStageChanged = ($this->getStageId() !== $this->getNewStageId());
				$isEmptyFields = empty($this->getFields());
				if($isStageChanged && !$isEmptyFields)
				{
					return static::ACTION_MOVE_UPDATE;
				}

				if($isStageChanged && $isEmptyFields)
				{
					return static::ACTION_MOVE;
				}

				return static::ACTION_UPDATE;
			}

			return static::ACTION_ADD;
		}
	}

	return parent::getAction();
}