Prevent product categories from being overwritten during a Product Set update. [datafeedr][dfrps][dfrpswc]

prevent-category-override.php

<?php

/**
 * Get all Term IDs this product is associated with and store them as an array
 * in the postmeta table keyed by "_custom_product_cat_ids".
 *
 * @param array $post Array containing WordPress Post information.
 * @param array $product Array containing Datafeedr Product information.
 * @param array $set Array containing Product Set information.
 * @param string $action Either "update" or "insert" depending on what the Product Set is doing.
 *
 * @return array Updated $post array.
 */
function mycode_save_custom_categories( $post, $product, $set, $action ) {

	// Skip if we are importing the product for the first time.
	if ( 'update' != $action ) {
		return $post;
	}

	// Get the Term IDs that this product's Product Set is associated with.
	$this_product_set_term_ids = ( isset( $set['postmeta']['_dfrps_cpt_terms'][0] ) ) ? unserialize( $set['postmeta']['_dfrps_cpt_terms'][0] ) : [];

	// Get the Term IDs that this product is associated with in other Product Sets (excluding the current Product Set).
	$other_product_set_term_ids = dfrpswc_get_all_term_ids_for_product( $post, $set );

	// Get the Term IDs that this product is associated with via customization after import.
	$custom_term_ids = wp_get_post_terms( $post['ID'], DFRPSWC_TAXONOMY, [ 'fields' => 'ids' ] );

	// Merge, convert all to integers and uniquify all Term IDs.
	$term_ids = array_merge( $this_product_set_term_ids, $other_product_set_term_ids, $custom_term_ids );
	$term_ids = array_unique( array_map( 'absint', $term_ids ) );

	update_post_meta( $post['ID'], '_custom_product_cat_ids', $term_ids );

	return $post;
}

add_filter( 'dfrpswc_filter_post_array', 'mycode_save_custom_categories', 20, 4 );

/**
 * Retrieves the Term IDs set by mycode_save_custom_categories() and adds them to the
 * $taxonomies array for 'product_cat'.
 *
 * @param array $taxonomies Array keyed by taxonomy name and having values of taxonomy values.
 * @param array $post Array containing WordPress Post information.
 * @param array $product Array containing Datafeedr Product information.
 * @param array $set Array containing Product Set information.
 * @param string $action Either "update" or "insert" depending on what the Product Set is doing.
 *
 * @return array Updated $taxonomies array.
 */
function mycode_restore_saved_custom_categories( $taxonomies, $post, $product, $set, $action ) {

	// Skip if we are importing the product for the first time.
	if ( 'update' != $action ) {
		return $taxonomies;
	}

	// Get Term IDs saved by mycode_save_custom_categories().
	$term_ids = get_post_meta( $post['ID'], '_custom_product_cat_ids', true );
	$term_ids = ( is_array( $term_ids ) ) ? $term_ids : [];

	$taxonomies['product_cat'] = $term_ids;

	return $taxonomies;
}

add_filter( 'dfrpswc_filter_taxonomy_array', 'mycode_restore_saved_custom_categories', 20, 5 );