Add ACF CPT products on-the-fly to a Gravity Form

functions.php

//
// Shop Order Form - Allow shop products to be added to the GF on the fly.
//
// Products are defined in an ACF CPT. These products may be purchased via a Gravity Form.
// The base form should have all fields required, except without products.
// The product fields will be added immediately above the Shipping field.
//
add_filter( 'gform_pre_render_7', 'populate_shop_products' );
add_filter( 'gform_pre_validation_7', 'populate_shop_products' );
add_filter( 'gform_pre_submission_filter_7', 'populate_shop_products' );
add_filter( 'gform_admin_pre_render_7', 'populate_shop_products' );
function populate_shop_products( $form ) {
  // Is the person a logged in member?
	$is_a_member = is_valid_user();

	// Grab a list of ACF Shop Products
	$product_query_args = [
		'post_type' => 'shop-product',
		'post_status' => 'publish',
		'posts_per_page' => -1,
		'orderby' => 'menu_order, date',
		'order' => 'ASC'
	];

	$starting_field_id = 0;

	foreach( $form['fields'] as $field ) {
		if( $field->id > $starting_field_id ) {
			$starting_field_id = $field->id;
		}
	}
	$starting_field_id++;
	
	$product_query = new WP_Query($product_query_args);
	if ($product_query->have_posts()) {
		while ($product_query->have_posts()) {
			$product_query->the_post();

			$product_id = get_the_ID();

			$product_name = get_the_title($product_id);
			$image_url = get_field( 'image', $product_id );
			$member_only = get_field( 'members_only', $product_id );
			$product_price = get_field( 'price', $product_id );

			//fb_log('product '.$product_id.': '.$product_name.' = '.$product_price);
			//fb_log('member_only:'.bool2str($member_only).'  is_member:'.bool2str($is_a_member));
			$show_product = true;
			if ( !( ($member_only) && (!$is_a_member) ) ) {

				$new_product['type'] = 'product';
				$new_product['id'] = $starting_field_id;
				$new_product['label'] = $product_name;
				$new_product['inputType'] = 'singleproduct';
				$new_product['basePrice'] =  floatval( $product_price );
				$new_product['enableCalculation'] = true;
				$new_product['disableQuantity'] = false;
				$new_product['defaultValue'] = 0;

				$new_product['inputs'] = array(
					array(
						'id'    => $starting_field_id.'.1',
						'label' => $product_name,
						'name'  => 'param_product'
					),
					array(
						'id'    => $starting_field_id.'.2',
						'label' => 'Price',
						'name'  => 'param_price'
					),
					array(
						'id'    => $starting_field_id.'.3',
						'label' => 'Quantity',
						'name'  => 'param_qty'
					),
				);

				$new_field = GF_Fields::create( $new_product );

				// Where is the shipping field
				$shipping_field_position = -1;
				foreach( $form['fields'] as $field ) {
					$shipping_field_position++;
					if ( $field->type == 'shipping' ) {
						break;
					}
				}
				// Insert the new field before the Shippinng field
				if ( $shipping_field_position >= 0 ) {
					$fields_before = array_slice( $form['fields'], 0, $shipping_field_position );
					$field_after = array_slice( $form['fields'], $shipping_field_position, count($form['fields'])-1 );
					$fields_before[] = $new_field;
				}
				$form['fields'] = array_merge( $fields_before, $field_after );
			}
		}
	}
    return $form;
}