Replace product's [Buy Now] button URL with link to lowest priced product from the Comparison Set. [datafeedr][dfrcs][woocommerce]

replace-buy-url-with-cheapest-from-compset.php

<?php

/**
 * Replace product's [Buy Now] button URL with link to lowest priced product from
 * the Comparison Set.
 *
 * If a Comparison Set does not exist for the product or one has not been cached
 * or the number of products returned does not meet the minimum required products
 * specified in the "Minimum Number of Results" field, then this will just return
 * the default $url.
 *
 * @param string $url Product link
 * @param WC_Product $product
 *
 * @return string URL of product.
 */
function mycode_replace_buy_url_with_url_of_lowest_priced_product( $url, $product ) {

	$source            = dfrcs_wc_get_source_of_product( $product );
	$source['context'] = 'wc_single_product_page';

	$compset = new Dfrcs( $source );

	// If compset is not cached, return default $url.
	if ( ! $compset->cached ) {
		return $url;
	}

	// If compset does not contain a lowest price product field, return default $url.
	if ( empty( $compset->lowest_priced_product ) ) {
		return $url;
	}

	// If compset is not being displayed because of min product requirement, return default $url.
	if ( ! $compset->meets_min_num_product_requirement() ) {
		return $url;
	}

	$url = dfrcs_url( $compset->lowest_priced_product );

	return $url;
}

add_filter( 'woocommerce_product_add_to_cart_url', 'mycode_replace_buy_url_with_url_of_lowest_priced_product', 20, 2 );