Add support for product reference field

I'm using reference field for commerce product in node entity and using inline entity form to edit it in node. After declaring this field in node form I get error:

TypeError: Argument 1 passed to Drupal\commerce_bulk\BulkVariationsCreator::getProductVariation() must be an instance of Drupal\commerce_product\Entity\Product, null given, called in
/modules/contrib/commerce_bulk/commerce_bulk.module on line 61 in
/modules/contrib/commerce_bulk/src/BulkVariationsCreator.php on line 105 #0
/modules/contrib/commerce_bulk/commerce_bulk.module(61): Drupal\commerce_bulk\BulkVariationsCreator->getProductVariation(NULL)

This error is occurred because this line is incorrect for my case:

$product = $form_state->getFormObject()->getEntity();

Because $form_state was generated for node form not for product form.

I have quick fix for me but I think it's not a solution. I used this line after previous:

if (get_class($product) == 'Drupal\node\Entity\Node') {
   $product = $product->get('field_product')->entity;
}

Also this line was working instead of original line:

$product = $context['items']->getEntity();

field_product — is my reference field.

Also after clicking generation button I got error:

TypeError: Argument 1 passed to Drupal\commerce_bulk\BulkVariationsCreator::getAttributeFieldOptionIds() must be an instance of Drupal\commerce_product\Entity\ProductVariation, boolean given, called in
/modules/contrib/commerce_bulk/src/BulkVariationsCreator.php on line 287 in
/modules/contrib/commerce_bulk/src/BulkVariationsCreator.php on line 397 #0
/modules/contrib/commerce_bulk/src/BulkVariationsCreator.php(287): Drupal\commerce_bulk\BulkVariationsCreator->getAttributeFieldOptionIds(false)

Here we have the same situation, because the next code is incorrect for my case:

$ief_id = $form['variations']['widget']['#ief_id'];

Because node form doesn't include this.

I added the next code for fixing (it works only for me):

if (!empty($form['field_product']['widget'][0]['inline_entity_form']['variations']['widget']['#ief_id'])) {
   $ief_id = $form['field_product']['widget'][0]['inline_entity_form']['variations']['widget']['#ief_id'];
}

field_product — is my reference field.

I think solution of this is simple but I didn't find it for now. I'll be searching it for nearest time. But If I will not be able to do it I'll use this quick solution. But it will not work for reference fields with different name. Also I'm not sure that my solution work correctly.