WooCommerce FIX: Product reviews "Show more comments" AJAX loading

wc-product-reviews-load-more-fix.php

<?php
/* Plugin Name: WooCommerce FIX: Product reviews "Show more comments" AJAX loading
 * Description: Fixes duplicated reviews pagination AJAX loading and prematurely hidden "Show more comments" button
 * in WooCommerce product editor. Place this file in the /wp-content/mu-plugins/ directory or copy all the code after
 * the exit statement to your theme file functions.php
 * Author: https://github.com/master-roma
 */

defined( 'ABSPATH' ) || exit;

/**
 * Fix #1:
 * WordPress admin JS counts only rows with class "comment".
 * WooCommerce reviews have class "review", so add "comment" too.
 */
add_filter(
	'comment_class',
	function ( $classes, $css_class, $comment_id, $comment, $post_id ) {
		if ( ! is_admin() || ! $comment instanceof WP_Comment ) {
			return $classes;
		}

		if ( 'product' !== get_post_type( (int) $comment->comment_post_ID ) ) {
			return $classes;
		}

		if ( ! in_array( 'comment', $classes, true ) ) {
			$classes[] = 'comment';
		}

		return $classes;
	},
	10,
	5
);

/**
 * Fix #2:
 * Force "load more" to load 10 rows, not the WordPress default 20,
 * and correct the button visibility after each AJAX request.
 */
add_action(
	'admin_footer-post.php',
	function () {
		$screen = function_exists( 'get_current_screen' ) ? get_current_screen() : null;

		if ( ! $screen || 'product' !== $screen->post_type ) {
			return;
		}

		$post_id = isset( $_GET['post'] ) ? absint( $_GET['post'] ) : 0;

		if ( ! $post_id ) {
			return;
		}

		$total = (int) get_comments(
			array(
				'post_id'      => $post_id,
				'count'        => true,
				'orderby'      => 'none',
				'type__not_in' => array( 'note' ),
			)
		);
		?>
		<script>
		(function($) {
			var wcProductReviewsTotal = <?php echo wp_json_encode( $total ); ?>;
			var wcProductReviewsPerPage = 10;

			function countLoadedRows() {
				return $('#the-comment-list tr[id^="comment-"]:visible').length;
			}

			function updateShowCommentsButton() {
				var $button = $('#show-comments');

				if (!$button.length) {
					return;
				}

				if (countLoadedRows() >= wcProductReviewsTotal) {
					$button.hide();
				} else {
					$button.show();
				}
			}

			function isGetCommentsAjax(settings) {
				if (!settings || !settings.data) {
					return false;
				}

				if (typeof settings.data === 'string') {
					return settings.data.indexOf('action=get-comments') !== -1;
				}

				return settings.data.action === 'get-comments';
			}

			$(function() {
				if (!window.commentsBox || typeof window.commentsBox.get !== 'function') {
					return;
				}

				window.commentsBox.load = function(total) {
					this.st = countLoadedRows();
					this.total = wcProductReviewsTotal || total;

					this.get(this.total, wcProductReviewsPerPage);

					return false;
				};

				$(document).ajaxComplete(function(event, xhr, settings) {
					if (!isGetCommentsAjax(settings)) {
						return;
					}

					window.setTimeout(updateShowCommentsButton, 0);
				});

				updateShowCommentsButton();
			});
		})(jQuery);
		</script>
		<?php
	}
);