WooCommerce - Display a list of variable products priced by a single or several variant states (attributes)

sym-woo-extensions.php

<?php
/**
 * Plugin Name:       SYM Woo Extensions
 * Plugin URI:        https://symphonyagency.com
 * Description:       A set of utilities for use with WooCommerce
 * Version:           1.0.0
 * Author:			  Chris Jenkins
 * Author URI:        http://symphonyagency.com
 * License:           GPL3
 * Text Domain:       sym-woo
 */

// We need to retrieve the product level variation ID based on a combination of terms
function get_product_variation_id($product_id, $attributes ) {

	$variation_id = find_matching_product_variation_id ( $product_id, $attributes);

	return $variation_id;
}

function find_matching_product_variation_id($product_id, $attributes)
{
	return (new \WC_Product_Data_Store_CPT())->find_matching_product_variation(
		new \WC_Product($product_id),
		$attributes
	);
}

// When we have a product ID and a variation ID, we need to retrieve the price for that variation
function get_variation_price_by_id($product_id, $variation_id){
	$product = new WC_Product_Variable($product_id);
	$variations = $product->get_available_variations();
	foreach ($variations as $variation) {
		if($variation['variation_id'] == $variation_id){
			$display_regular_price = $variation['display_regular_price'];
			$display_price = $variation['display_price'];

            $priceArray = array(
                'display_regular_price' => $display_regular_price,
                'display_price' => $display_price
            );
            $priceObject = (object)$priceArray;
            return $priceObject;

        }
	}

}

// And here's the display function for the shortcode using the combination of above
function single_variation_display($atts){

	$atts = shortcode_atts(
		array(
			'category'   => '',
			'size'  => '',
			'foundation' => '',
		), $atts );

	$product_cat = $atts['category'];
	$product_size = $atts['size'];
	$product_foundation = $atts['foundation'];
	$attributes = [
		'attribute_pa_size' => $product_size,
		'attribute_pa_box-spring' => $product_foundation
	];

	$currency_symbol = get_woocommerce_currency_symbol();

	$product_display = '<div class="woocommerce columns-3 "><ul class="products columns-3">';

	$args = array(
		'posts_per_page' => -1,
		'product_cat' => $product_cat,
		'post_type' => 'product',
		'orderby' => 'title',
	);
	$the_query = new WP_Query( $args );
	// The Loop
	while ( $the_query->have_posts() ) {
		$the_query->the_post();
		$product_id = get_the_ID();
		$product = wc_get_product($product_id);
		// Get our variation ID
		$variation_ID = get_product_variation_id( $product_id, $attributes );
		ob_start();
		?>

        <li <?php wc_product_class( '', $product_id ); ?>>
            <?php do_action('woocommerce_before_shop_loop_item'); ?>

            <span class="product-images">

              <?php
              /**
               * woocommerce_before_shop_loop_item_title hook
               *
               * @hooked woocommerce_show_product_loop_sale_flash - 10
               * @hooked woocommerce_template_loop_product_thumbnail - 10
               */
              do_action('woocommerce_before_shop_loop_item_title');
              ?>

            </span>

            <div class="product-details">

                <div class="product-details-container">

                    <?php
                    /**
                     * woocommerce_shop_loop_item_title hook
                     *
                     * @hooked woocommerce_template_loop_product_title - 10
                     */
                    //we are not using this hook in Evolve Plus Theme, because the title produced is not a link,
                    //we are using the following at line 79 <h3 class="product-title"><a...</a></h3>
                    //do_action( 'woocommerce_shop_loop_item_title' );
                    ?>

                    <h3 class="product-title"><span><?php the_title(); ?></span></h3>

                    <div class="clearfix">
                        <?php
						$variation_price = get_variation_price_by_id($product_id, $variation_ID);
						$current_price = '<ins><span class="woocommerce-Price-amount amount"><span class="woocommerce-Price-currencySymbol">'. $currency_symbol .'</span>'.$variation_price -> display_price.'</span></ins>';
						$on_sale = $product->is_on_sale();
						if($on_sale){
							echo '<span class="onsale">Sale!</span>';
							$regular_price = '<del><span class="woocommerce-Price-amount amount"><span class="woocommerce-Price-currencySymbol">'. $currency_symbol .'</span>'.$variation_price -> display_regular_price.'</span></del>';
						}
                        ?>
						<span class="price">Starting at <?php echo $regular_price.' '.$current_price; ?> </span>
						<?php
						unset($regular_price);
						unset($current_price);
						?>
                    </div>

                </div>

            </div>

            <?php
            /**
             * woocommerce_after_shop_loop_item hook
             *
             * @hooked woocommerce_template_loop_add_to_cart - 10
             */
            do_action('woocommerce_after_shop_loop_item');
            ?>

        </li>


	<?php
		$product_display .= ob_get_clean();
	}
	wp_reset_postdata();
	$product_display .='</ul></div>';
	return $product_display;
}

add_shortcode('single-variation','single_variation_display');