code: private function init($name)
      {
          if (null === $name) {
              $name = $this->default;
          }
  
          if (!isset(static::$orderMap[ $name ])) {
              throw new \InvalidArgumentException(sprintf(
                  'Unknown status name "%s" for "%s"',
                  $name,
                  static::class
              ));
          }
  
          $this->name  = $name;
          $this->order = static::$orderMap[ $name ];
      }
docs: Initialize this state.
  
  @param string $name
  
  @throws \InvalidArgumentException