et_product_term_ids( $product_id, 'product_cat' );

	foreach ( $product_cats as $product_cat ) {
		$product_cats = array_merge( $product_cats, get_ancestors( $product_cat, 'product_cat' ) );
	}

	return $product_cats;
}

/**
 * Gets data about an attachment, such as alt text and captions.
 *
 * @since 2.6.0
 *
 * @param int|null        $attachment_id Attachment ID.
 * @param WC_Product|bool $product WC_Product object.
 *
 * @return array
 */
function wc_get_product_attachment_props( $attachment_id = null, $product = false ) {
	$props      = array(
		'title'   => '',
		'caption' => '',
		'url'     => '',
		'alt'     => '',
		'src'     => '',
		'srcset'  => false,
		'sizes'   => false,
	);
	$attachment = get_post( $attachment_id );

	if ( $attachment && 'attachment' === $attachment->post_type ) {
		$props['title']   = wp_strip_all_tags( $attachment->post_title );
		$props['caption'] = wp_strip_all_tags( $attachment->post_excerpt );
		$props['url']     = wp_get_attachment_url( $attachment_id );

		// Alt text.
		$alt_text = array( wp_strip_all_tags( get_post_meta( $attachment_id, '_wp_attachment_image_alt', true ) ), $props['caption'], wp_strip_all_tags( $attachment->post_title ) );

		if ( $product && $product instanceof WC_Product ) {
			$alt_text[] = wp_strip_all_tags( get_the_title( $product->get_id() ) );
		}

		$alt_text     = array_filter( $alt_text );
		$props['alt'] = $alt_text ? reset( $alt_text ) : '';

		/**
		 * Filters the size for the full gallery image.
		 *
		 * @param string $size Image size name.
		 *
		 * @since 2.6.0
		 */
		$full_size           = apply_filters( 'woocommerce_gallery_full_size', apply_filters( 'woocommerce_product_thumbnails_large_size', 'full' ) );
		$src                 = wp_get_attachment_image_src( $attachment_id, $full_size );
		$props['full_src']   = $src[0] ?? null;
		$props['full_src_w'] = $src[1] ?? null;
		$props['full_src_h'] = $src[2] ?? null;

		$gallery_thumbnail = wc_get_image_size( 'gallery_thumbnail' );
		/**
		 * Filters the size for the gallery thumbnail.
		 *
		 * @param array $size Array containing width and height dimensions.
		 *
		 * @since 2.6.0
		 */
		$gallery_thumbnail_size           = apply_filters( 'woocommerce_gallery_thumbnail_size', array( $gallery_thumbnail['width'], $gallery_thumbnail['height'] ) );
		$src                              = wp_get_attachment_image_src( $attachment_id, $gallery_thumbnail_size );
		$props['gallery_thumbnail_src']   = $src[0] ?? null;
		$props['gallery_thumbnail_src_w'] = $src[1] ?? null;
		$props['gallery_thumbnail_src_h'] = $src[2] ?? null;

		/**
		 * Filters the thumbnail size.
		 *
		 * @param string $size Image size name.
		 *
		 * @since 2.6.0
		 */
		$thumbnail_size       = apply_filters( 'woocommerce_thumbnail_size', 'woocommerce_thumbnail' );
		$src                  = wp_get_attachment_image_src( $attachment_id, $thumbnail_size );
		$props['thumb_src']   = $src[0] ?? null;
		$props['thumb_src_w'] = $src[1] ?? null;
		$props['thumb_src_h'] = $src[2] ?? null;

		/**
		 * Filters the size for the gallery image.
		 *
		 * @param string $size Image size name.
		 *
		 * @since 2.6.0
		 */
		$image_size      = apply_filters( 'woocommerce_gallery_image_size', 'woocommerce_single' );
		$src             = wp_get_attachment_image_src( $attachment_id, $image_size );
		$props['src']    = $src[0] ?? null;
		$props['src_w']  = $src[1] ?? null;
		$props['src_h']  = $src[2] ?? null;
		$props['srcset'] = function_exists( 'wp_get_attachment_image_srcset' ) ? wp_get_attachment_image_srcset( $attachment_id, $image_size ) : false;
		$props['sizes']  = function_exists( 'wp_get_attachment_image_sizes' ) ? wp_get_attachment_image_sizes( $attachment_id, $image_size ) : false;
	}
	return $props;
}

/**
 * Get product visibility options.
 *
 * @since 3.0.0
 * @return array
 */
function wc_get_product_visibility_options() {
	return apply_filters(
		'woocommerce_product_visibility_options',
		array(
			CatalogVisibility::VISIBLE => __( 'Shop and search results', 'woocommerce' ),
			CatalogVisibility::CATALOG => __( 'Shop only', 'woocommerce' ),
			CatalogVisibility::SEARCH  => __( 'Search results only', 'woocommerce' ),
			CatalogVisibility::HIDDEN  => __( 'Hidden', 'woocommerce' ),
		)
	);
}

/**
 * Get product tax class options.
 *
 * @since 3.0.0
 * @return array
 */
function wc_get_product_tax_class_options() {
	$tax_classes           = WC_Tax::get_tax_classes();
	$tax_class_options     = array();
	$tax_class_options[''] = __( 'Standard', 'woocommerce' );

	if ( ! empty( $tax_classes ) ) {
		foreach ( $tax_classes as $class ) {
			$tax_class_options[ sanitize_title( $class ) ] = $class;
		}
	}
	return $tax_class_options;
}

/**
 * Get stock status options.
 *
 * @since 3.0.0
 * @return array
 */
function wc_get_product_stock_status_options() {
	return apply_filters(
		'woocommerce_product_stock_status_options',
		array(
			ProductStockStatus::IN_STOCK     => __( 'In stock', 'woocommerce' ),
			ProductStockStatus::OUT_OF_STOCK => __( 'Out of stock', 'woocommerce' ),
			ProductStockStatus::ON_BACKORDER => __( 'On backorder', 'woocommerce' ),
		)
	);
}

/**
 * Get backorder options.
 *
 * @since 3.0.0
 * @return array
 */
function wc_get_product_backorder_options() {
	return array(
		'no'     => __( 'Do not allow', 'woocommerce' ),
		'notify' => __( 'Allow, but notify customer', 'woocommerce' ),
		'yes'    => __( 'Allow', 'woocommerce' ),
	);
}

/**
 * Get related products based on product category and tags.
 *
 * @since  3.0.0
 * @param  int   $product_id  Product ID.
 * @param  int   $limit       Limit of results.
 * @param  array $exclude_ids Exclude IDs from the results.
 * @param  array $related_by  Related by category and tags boolean flags.
 * @return array
 */
function wc_get_related_products( $product_id, $limit = 5, $exclude_ids = array(), $related_by = array() ) {
	// Log an error if the limit is not an integer since this is what we expect.
	// However this is not a problem and we can continue.
	if ( ! is_int( $limit ) ) {
		wc_get_logger()->error(
			sprintf(
				'Invalid limit type passed to wc_get_related_products. Expected integer, got %s with value: %s',
				gettype( $limit ),
				wp_json_encode( $limit )
			),
			array( 'source' => 'wc_get_related_products' )
		);
	}

	// If the limit is not numeric, set it to null.
	$limit = is_numeric( $limit ) ? (int) $limit : null;

	if ( null === $limit ) {
		return array();
	}

	$product_id     = absint( $product_id );
	$limit          = $limit >= -1 ? $limit : 5;
	$exclude_ids    = array_merge( array( 0, $product_id ), $exclude_ids );
	$transient_name = 'wc_related_' . $product_id;
	$query_args     = http_build_query(
		array(
			'limit'       => $limit,
			'exclude_ids' => $exclude_ids,
			'related_by'  => $related_by,
		)
	);

	$transient     = get_transient( $transient_name );
	$related_posts = $transient && is_array( $transient ) && isset( $transient[ $query_args ] ) ? $transient[ $query_args ] : false;

	// We want to query related posts if they are not cached, or we don't have enough.
	if ( false === $related_posts || count( $related_posts ) < $limit ) {

		$cats_array = apply_filters( 'woocommerce_product_related_posts_relate_by_category', true, $product_id ) ? apply_filters( 'woocommerce_get_related_product_cat_terms', wc_get_product_term_ids( $product_id, 'product_cat' ), $product_id ) : array();
		$tags_array = apply_filters( 'woocommerce_product_related_posts_relate_by_tag', true, $product_id ) ? apply_filters( 'woocommerce_get_related_product_tag_terms', wc_get_product_term_ids( $product_id, 'product_tag' ), $product_id ) : array();

		// Don't bother if none are set, unless woocommerce_product_related_posts_force_display is set to true in which case all products are related.
		if ( empty( $cats_array ) && empty( $tags_array ) && ! apply_filters( 'woocommerce_product_related_posts_force_display', false, $product_id ) ) {
			$related_posts = array();
		} else {
			$data_store    = WC_Data_Store::load( 'product' );
			$related_posts = $data_store->get_related_products( $cats_array, $tags_array, $exclude_ids, $limit + 10, $product_id );
		}

		if ( $transient && is_array( $transient ) ) {
			$transient[ $query_args ] = $related_posts;
		} else {
			$transient = array( $query_args => $related_posts );
		}

		set_transient( $transient_name, $transient, DAY_IN_SECONDS );
	}

	$related_posts = apply_filters(
		'woocommerce_related_products',
		$related_posts,
		$product_id,
		array(
			'limit'        => $limit,
			'excluded_ids' => $exclude_ids,
		)
	);

	$related_posts = is_array( $related_posts ) ? $related_posts : array();

	if ( apply_filters( 'woocommerce_product_related_posts_shuffle', true ) ) {
		shuffle( $related_posts );
	}

	return array_slice( $related_posts, 0, $limit );
}

/**
 * Retrieves product term ids for a taxonomy.
 *
 * @since  3.0.0
 * @param  int    $product_id Product ID.
 * @param  string $taxonomy   Taxonomy slug.
 * @return array
 */
function wc_get_product_term_ids( $product_id, $taxonomy ) {
	$terms = get_the_terms( $product_id, $taxonomy );
	return ( empty( $terms ) || is_wp_error( $terms ) ) ? array() : wp_list_pluck( $terms, 'term_id' );
}

/**
 * For a given product, and optionally price/qty, work out the price with tax included, based on store settings.
 *
 * @since  3.0.0
 * @param  WC_Product $product WC_Product object.
 * @param  array      $args Optional arguments to pass product quantity and price.
 * @return float|string Price with tax included, or an empty string if price calculation failed.
 */
function wc_get_price_including_tax( $product, $args = array() ) {
	$args = wp_parse_args(
		$args,
		array(
			'qty'   => '',
			'price' => '',
		)
	);

	$price = '' !== $args['price'] ? max( 0.0, (float) $args['price'] ) : (float) $product->get_price();
	$qty   = '' !== $args['qty'] ? max( 0.0, (float) $args['qty'] ) : 1;

	if ( empty( $qty ) ) {
		return 0.0;
	}

	$line_price   = $price * $qty;
	$return_price = $line_price;

	if ( $product->is_taxable() ) {
		if ( ! wc_prices_include_tax() ) {
			// If the customer is exempt from VAT, set tax total to 0.
			if ( ! empty( WC()->customer ) && WC()->customer->get_is_vat_exempt() ) {
				$taxes_total = 0.00;
			} else {
				$tax_rates = WC_Tax::get_rates( $product->get_tax_class() );
				$taxes     = WC_Tax::calc_tax( $line_price, $tax_rates, false );

				if ( 'yes' === get_option( 'woocommerce_tax_round_at_subtotal' ) ) {
					$taxes_total = array_sum( $taxes );
				} else {
					$taxes_total = array_sum( array_map( 'wc_round_tax_total', $taxes ) );
				}
			}

			$return_price = NumberUtil::round( $line_price + $taxes_total, wc_get_price_decimals() );
		} else {
			$tax_rates      = WC_Tax::get_rates( $product->get_tax_class() );
			$base_tax_rates = WC_Tax::get_base_tax_rates( $product->get_tax_class( 'unfiltered' ) );

			/**
			 * If the customer is exempt from VAT, remove the taxes here.
			 * Either remove the base or the user taxes depending on woocommerce_adjust_non_base_location_prices setting.
			 */
			if ( ! empty( WC()->customer ) && WC()->customer->get_is_vat_exempt() ) { // @codingStandardsIgnoreLine.
				$remove_taxes = apply_filters( 'woocommerce_adjust_non_base_location_prices', true ) ? WC_Tax::calc_tax( $line_price, $base_tax_rates, true ) : WC_Tax::calc_tax( $line_price, $tax_rates, true );

				if ( 'yes' === get_option( 'woocommerce_tax_round_at_subtotal' ) ) {
					$remove_taxes_total = array_sum( $remove_taxes );
				} else {
					$remove_taxes_total = array_sum( array_map( 'wc_round_tax_total', $remove_taxes ) );
				}

				$return_price = NumberUtil::round( $line_price - $remove_taxes_total, wc_get_price_decimals() );

				/**
			 * The woocommerce_adjust_non_base_location_prices filter can stop base taxes being taken off when dealing with out of base locations.
			 * e.g. If a product costs 10 including tax, all users will pay 10 regardless of location and taxes.
			 * This feature is experimental @since 2.4.7 and may change in the future. Use at your risk.
			 */
			} elseif ( $tax_rates !== $base_tax_rates && apply_filters( 'woocommerce_adjust_non_base_location_prices', true ) ) {
				$base_taxes   = WC_Tax::calc_tax( $line_price, $base_tax_rates, true );
				$modded_taxes = WC_Tax::calc_tax( $line_price - array_sum( $base_taxes ), $tax_rates, false );

				if ( 'yes' === get_option( 'woocommerce_tax_round_at_subtotal' ) ) {
					$base_taxes_total   = array_sum( $base_taxes );
					$modded_taxes_total = array_sum( $modded_taxes );
				} else {
					$base_taxes_total   = array_sum( array_map( 'wc_round_tax_total', $base_taxes ) );
					$modded_taxes_total = array_sum( array_map( 'wc_round_tax_total', $modded_taxes ) );
				}

				$return_price = NumberUtil::round( $line_price - $base_taxes_total + $modded_taxes_total, wc_get_price_decimals() );
			}
		}
	}
	return apply_filters( 'woocommerce_get_price_including_tax', $return_price, $qty, $product );
}

/**
 * For a given product, and optionally price/qty, work out the price with tax excluded, based on store settings.
 *
 * @since  3.0.0
 * @param  WC_Product $product WC_Product object.
 * @param  array      $args Optional arguments to pass product quantity and price.
 * @return float|string Price with tax excluded, or an empty string if price calculation failed.
 */
function wc_get_price_excluding_tax( $product, $args = array() ) {
	if ( ! ( $product instanceof WC_Product ) ) {
		return '';
	}

	$args = wp_parse_args(
		$args,
		array(
			'qty'   => '',
			'price' => '',
		)
	);

	$price = '' !== $args['price'] ? max( 0.0, (float) $args['price'] ) : (float) $product->get_price();
	$qty   = '' !== $args['qty'] ? max( 0.0, (float) $args['qty'] ) : 1;

	if ( empty( $qty ) ) {
		return 0.0;
	}

	$line_price = $price * $qty;

	if ( $product->is_taxable() && wc_prices_include_tax() ) {
		$order       = ArrayUtil::get_value_or_default( $args, 'order' );
		$customer_id = $order ? $order->get_customer_id() : 0;
		$tax_rates   = false;

		if ( apply_filters( 'woocommerce_adjust_non_base_location_prices', true ) ) {
			$tax_rates = WC_Tax::get_base_tax_rates( $product->get_tax_class( 'unfiltered' ) );
		} elseif ( $customer_id ) {
			$customer  = wc_get_container()->get( LegacyProxy::class )->get_instance_of( WC_Customer::class, $customer_id );
			$tax_rates = WC_Tax::get_rates( $product->get_tax_class(), $customer );
		} elseif ( is_object( $order ) && method_exists( $order, 'get_taxable_location' ) ) {
			$tax_location = $order->get_taxable_location();
			if ( is_array( $tax_location ) && isset( $tax_location['country'] ) ) {
				$tax_rates = WC_Tax::find_rates(
					array(
						'country'   => $tax_location['country'],
						'state'     => $tax_location['state'] ?? '',
						'postcode'  => $tax_location['postcode'] ?? '',
						'city'      => $tax_location['city'] ?? '',
						'tax_class' => $product->get_tax_class(),
					)
				);
			}
		}

		// Fallback if no tax rates were determined.
		if ( false === $tax_rates ) {
			$tax_rates = WC_Tax::get_rates( $product->get_tax_class(), null );
		}

		$remove_taxes = WC_Tax::calc_tax( $line_price, $tax_rates, true );
		$return_price = $line_price - array_sum( $remove_taxes ); // Unrounded since we're dealing with tax inclusive prices. Matches logic in cart-totals class. @see adjust_non_base_location_price.
	} else {
		$return_price = $line_price;
	}

	return apply_filters( 'woocommerce_get_price_excluding_tax', $return_price, $qty, $product );
}

/**
 * Returns the price including or excluding tax.
 *
 * By default it's based on the 'woocommerce_tax_display_shop' setting.
 * Set `$arg['display_context']` to 'cart' to base on the 'woocommerce_tax_display_cart' setting instead.
 *
 * @since  3.0.0
 * @since  7.6.0 Added `display_context` argument.
 *
 * @param  WC_Product $product WC_Product object.
 * @param  array      $args Optional arguments to pass product quantity and price.
 * @return float
 */
function wc_get_price_to_display( $product, $args = array() ) {
	$args = wp_parse_args(
		$args,
		array(
			'qty'             => 1,
			'price'           => $product->get_price(),
			'display_context' => 'shop',
		)
	);

	$price       = $args['price'];
	$qty         = $args['qty'];
	$tax_display = get_option(
		'cart' === $args['display_context'] ? 'woocommerce_tax_display_cart' : 'woocommerce_tax_display_shop'
	);

	return TaxDisplayMode::INCLUSIVE === $tax_display ?
		wc_get_price_including_tax(
			$product,
			array(
				'qty'   => $qty,
				'price' => $price,
			)
		) :
		wc_get_price_excluding_tax(
			$product,
			array(
				'qty'   => $qty,
				'price' => $price,
			)
		);
}

/**
 * Returns the product categories in a list.
 *
 * @since 11.2.0 Added the `$orderby` argument.
 *
 * @param int    $product_id Product ID.
 * @param string $sep (default: ', ').
 * @param string $before (default: '').
 * @param string $after (default: '').
 * @param string $orderby Optional ordering mode. Accepts 'name' to naturally order assigned terms by name,
 *                        ignoring the category order termmeta that the default path honors, or 'breadcrumb'
 *                        to order assigned terms by ancestry path, comparing category order, natural name,
 *                        and term ID at each level of the rendered hierarchy. Any other value preserves
 *                        WordPress term-list order; a non-empty unsupported value also triggers a
 *                        `_doing_it_wrong()` notice. Default empty string.
 * @return string|false|WP_Error
 */
function wc_get_product_category_list( $product_id, $sep = ', ', $before = '', $after = '', $orderby = '' ) {
	if ( ! in_array( $orderby, array( 'name', 'breadcrumb' ), true ) ) {
		if ( '' !== $orderby ) {
			wc_doing_it_wrong(
				__FUNCTION__,
				sprintf(
					/* translators: 1: the unsupported ordering mode that was passed. */
					__( 'Unsupported $orderby value "%1$s". Use "name", "breadcrumb", or an empty string for WordPress term-list order.', 'woocommerce' ),
					is_scalar( $orderby ) ? (string) $orderby : gettype( $orderby )
				),
				'11.2.0'
			);
		}

		return get_the_term_list( $product_id, 'product_cat', $before, $sep, $after );
	}

	$terms = get_the_terms( $product_id, 'product_cat' );

	if ( is_wp_error( $terms ) ) {
		return $terms;
	}

	if ( empty( $terms ) || ! is_array( $terms ) ) {
		return false;
	}

	$terms       = array_values( $terms );
	$should_sort = 1 < count( $terms );

	if ( 'name' === $orderby && $should_sort ) {
		usort(
			$terms,
			function ( $a, $b ) {
				$name_comparison = strnatcasecmp( (string) $a->name, (string) $b->name );

				return 0 !== $name_comparison ? $name_comparison : $a->term_id <=> $b->term_id;
			}
		);
	} elseif ( 'breadcrumb' === $orderby && $should_sort ) {
		$rendered_terms = array();

		foreach ( $terms as $term ) {
			$rendered_terms[ (int) $term->term_id ] = $term;
		}

		/*
		 * Resolve ancestors one batched query per hierarchy level rather than one query per
		 * ancestor. The batch is a cache prime, not the ordering data: get_ancestors() below reads
		 * it, and so does get_term_link() further down, because product_cat is registered with a
		 * hierarchical rewrite and therefore resolves each category's ancestry to build its
		 * permalink. Priming here makes the deep leaf-only case cheaper than not ordering at all.
		 */
		$known_ids = array_fill_keys( array_keys( $rendered_terms ), true );
		$frontier  = array();

		foreach ( $terms as $term ) {
			if ( $term->parent ) {
				$frontier[ (int) $term->parent ] = true;
			}
		}

		// Ancestry is filterable, so bound the walk rather than trusting it to terminate.
		$remaining_levels = 100;

		while ( $frontier && $remaining_levels-- > 0 ) {
			$frontier_ids = array_values( array_diff( array_keys( $frontier ), array_keys( $known_ids ) ) );

			if ( ! $frontier_ids ) {
				break;
			}

			$frontier_parents = get_terms(
				array(
					'taxonomy'               => 'product_cat',
					'include'                => $frontier_ids,
					'hide_empty'             => false,
					'fields'                 => 'id=>parent',
					'orderby'                => 'include',
					'update_term_meta_cache' => false,
				)
			);

			/*
			 * A filtered get_terms() can return any shape. Failing to prime is harmless; the
			 * get_ancestors() calls below just query for themselves.
			 */
			if ( is_wp_error( $frontier_parents ) || ! is_array( $frontier_parents ) ) {
				break;
			}

			$frontier = array();

			foreach ( $frontier_parents as $term_id => $parent_id ) {
				if ( ! is_numeric( $term_id ) || ! is_numeric( $parent_id ) ) {
					continue;
				}

				$known_ids[ (int) $term_id ] = true;

				if ( (int) $parent_id ) {
					$frontier[ (int) $parent_id ] = true;
				}
			}
		}

		update_termmeta_cache( array_keys( $rendered_terms ) );

		$term_orders = array();
		$term_paths  = array();

		foreach ( $terms as $term ) {
			$term_id    = (int) $term->term_id;
			$term_order = get_term_meta( $term_id, 'order', true );

			$term_orders[ $term_id ] = is_numeric( $term_order ) ? (int) $term_order : 0;

			$ancestor_ids = array_filter( (array) get_ancestors( $term_id, 'product_cat', 'taxonomy' ), 'is_numeric' );
			$ancestor_ids = array_map( 'intval', $ancestor_ids );
			// Cyclic ancestry can list the term itself among its own ancestors.
			$ancestor_ids = array_diff( array_unique( $ancestor_ids ), array( $term_id ) );

			$path   = array_reverse( array_values( $ancestor_ids ) );
			$path[] = $term_id;

			/*
			 * Rank on rendered terms only. Ancestors establish which term sits under which, but a
			 * category that is not in the output never contributes a sort key of its own, so the
			 * reason for the rendered order is always visible on the page.
			 */
			$term_paths[ $term_id ] = array_values(
				array_filter(
					$path,
					static function ( $step ) use ( $rendered_terms ) {
						return isset( $rendered_terms[ $step ] );
					}
				)
			);
		}

		usort(
			$terms,
			static function ( $a, $b ) use ( $rendered_terms, $term_orders, $term_paths ) {
				$a_path       = $term_paths[ (int) $a->term_id ];
				$b_path       = $term_paths[ (int) $b->term_id ];
				$shared_depth = min( count( $a_path ), count( $b_path ) );

				for ( $index = 0; $index < $shared_depth; $index++ ) {
					$a_term_id = $a_path[ $index ];
					$b_term_id = $b_path[ $index ];

					if ( $a_term_id === $b_term_id ) {
						continue;
					}

					if ( $term_orders[ $a_term_id ] !== $term_orders[ $b_term_id ] ) {
						return $term_orders[ $a_term_id ] <=> $term_orders[ $b_term_id ];
					}

					$path_comparison = strnatcasecmp(
						(string) $rendered_terms[ $a_term_id ]->name,
						(string) $rendered_terms[ $b_term_id ]->name
					);

					return 0 !== $path_comparison ? $path_comparison : $a_term_id <=> $b_term_id;
				}

				return count( $a_path ) <=> count( $b_path );
			}
		);
	}

	$links = array();

	foreach ( $terms as $term ) {
		$link = get_term_link( $term, 'product_cat' );

		if ( is_wp_error( $link ) ) {
			return $link;
		}

		$links[] = '<a href="' . esc_url( $link ) . '" rel="tag">' . $term->name . '</a>';
	}

	/*
	 * Fire core's own term_links-{$taxonomy} hook, so that ordered output stays filterable by exactly
	 * what already filters get_the_term_list().
	 */
	/** This filter is documented in wp-includes/category-template.php */
	$term_links = apply_filters( 'term_links-product_cat', $links ); // phpcs:ignore WordPress.NamingConventions.ValidHookName.UseUnderscores, WooCommerce.Commenting.CommentHooks.MissingSinceComment

	/*
	 * Validate what the filter handed back. Core's own path does not, and passing a non-array to
	 * implode() there raises a TypeError. Returning false keeps this path within the documented
	 * string|false|WP_Error contract instead; core's behaviour is deliberately left alone, since
	 * changing it would be a separate compatibility decision.
	 */
	if ( is_wp_error( $term_links ) ) {
		return $term_links;
	}

	if ( ! is_array( $term_links ) ) {
		return false;
	}

	return $before . implode( $sep, $term_links ) . $after;
}

/**
 * Returns the product tags in a list.
 *
 * @param int    $product_id Product ID.
 * @param string $sep (default: ', ').
 * @param string $before (default: '').
 * @param string $after (default: '').
 * @return string
 */
function wc_get_product_tag_list( $product_id, $sep = ', ', $before = '', $after = '' ) {
	return get_the_term_list( $product_id, 'product_tag', $before, $sep, $after );
}

/**
 * Callback for array filter to get visible only.
 *
 * @since  3.0.0
 * @param  WC_Product $product WC_Product object.
 * @return bool
 */
function wc_products_array_filter_visible( $product ) {
	return $product && is_a( $product, 'WC_Product' ) && $product->is_visible();
}

/**
 * Callback for array filter to get visible grouped products only.
 *
 * @since  3.1.0
 * @param  WC_Product $product WC_Product object.
 * @return bool
 */
function wc_products_array_filter_visible_grouped( $product ) {
	return $product && is_a( $product, 'WC_Product' ) && $product->is_viewable();
}

/**
 * Callback for array filter to get products the user can edit only.
 *
 * @since  3.0.0
 * @param  WC_Product $product WC_Product object.
 * @return bool
 */
function wc_products_array_filter_editable( $product ) {
	return $product && is_a( $product, 'WC_Product' ) && current_user_can( 'edit_product', $product->get_id() );
}

/**
 * Callback for array filter to get products the user can view only.
 *
 * @since  3.4.0
 * @param  WC_Product $product WC_Product object.
 * @return bool
 */
function wc_products_array_filter_readable( $product ) {
	return $product && is_a( $product, 'WC_Product' ) && current_user_can( 'read_product', $product->get_id() );
}

/**
 * Sort an array of products by a value.
 *
 * @since  3.0.0
 *
 * @param array  $products List of products to be ordered.
 * @param string $orderby Optional order criteria.
 * @param string $order Ascending or descending order.
 *
 * @return array
 */
function wc_products_array_orderby( $products, $orderby = 'date', $order = 'desc' ) {
	$orderby = strtolower( $orderby );
	$order   = strtolower( $order );
	switch ( $orderby ) {
		case 'title':
		case 'id':
		case 'date':
		case 'modified':
		case 'menu_order':
		case 'price':
			usort( $products, 'wc_products_array_orderby_' . $orderby );
			break;
		case 'none':
			break;
		default:
			shuffle( $products );
			break;
	}
	if ( 'desc' === $order ) {
		$products = array_reverse( $products );
	}
	return $products;
}

/**
 * Sort by title.
 *
 * @since  3.0.0
 * @param  WC_Product $a First WC_Product object.
 * @param  WC_Product $b Second WC_Product object.
 * @return int
 */
function wc_products_array_orderby_title( $a, $b ) {
	return strcasecmp( $a->get_name(), $b->get_name() );
}

/**
 * Sort by id.
 *
 * @since  3.0.0
 * @param  WC_Product $a First WC_Product object.
 * @param  WC_Product $b Second WC_Product object.
 * @return int
 */
function wc_products_array_orderby_id( $a, $b ) {
	if ( $a->get_id() === $b->get_id() ) {
		return 0;
	}
	return ( $a->get_id() < $b->get_id() ) ? -1 : 1;
}

/**
 * Sort by date.
 *
 * @since  3.0.0
 * @param  WC_Product $a First WC_Product object.
 * @param  WC_Product $b Second WC_Product object.
 * @return int
 */
function wc_products_array_orderby_date( $a, $b ) {
	if ( $a->get_date_created() === $b->get_date_created() ) {
		return 0;
	}
	return ( $a->get_date_created() < $b->get_date_created() ) ? -1 : 1;
}

/**
 * Sort by modified.
 *
 * @since  3.0.0
 * @param  WC_Product $a First WC_Product object.
 * @param  WC_Product $b Second WC_Product object.
 * @return int
 */
function wc_products_array_orderby_modified( $a, $b ) {
	if ( $a->get_date_modified() === $b->get_date_modified() ) {
		return 0;
	}
	return ( $a->get_date_modified() < $b->get_date_modified() ) ? -1 : 1;
}

/**
 * Sort by menu order.
 *
 * @since  3.0.0
 * @param  WC_Product $a First WC_Product object.
 * @param  WC_Product $b Second WC_Product object.
 * @return int
 */
function wc_products_array_orderby_menu_order( $a, $b ) {
	if ( $a->get_menu_order() === $b->get_menu_order() ) {
		return 0;
	}
	return ( $a->get_menu_order() < $b->get_menu_order() ) ? -1 : 1;
}

/**
 * Sort by price low to high.
 *
 * @since  3.0.0
 * @param  WC_Product $a First WC_Product object.
 * @param  WC_Product $b Second WC_Product object.
 * @return int
 */
function wc_products_array_orderby_price( $a, $b ) {
	if ( $a->get_price() === $b->get_price() ) {
		return 0;
	}
	return ( $a->get_price() < $b->get_price() ) ? -1 : 1;
}

/**
 * Queue a product for syncing at the end of the request.
 *
 * @param int $product_id Product ID.
 */
function wc_deferred_product_sync( $product_id ) {
	global $wc_deferred_product_sync;

	if ( empty( $wc_deferred_product_sync ) ) {
		$wc_deferred_product_sync = array();
	}

	$wc_deferred_product_sync[] = $product_id;
}

/**
 * See if the lookup table is being generated already.
 *
 * @since 3.6.0
 * @return bool
 */
function wc_update_product_lookup_tables_is_running() {
	$table_updates_pending = WC()->queue()->search(
		array(
			'status'   => 'pending',
			'group'    => 'wc_update_product_lookup_tables',
			'per_page' => 1,
		)
	);

	return (bool) count( $table_updates_pending );
}

/**
 * Populate lookup table data for products.
 *
 * @since 3.6.0
 */
function wc_update_product_lookup_tables() {
	global $wpdb;

	$is_cli          = Constants::is_true( 'WP_CLI' );
	$reviews_enabled = wc_reviews_enabled();

	// Note that the table is not yet generated.
	update_option( 'woocommerce_product_lookup_table_is_generating', true );

	// Make a row per product in lookup table.
	$wpdb->query(
		"
		INSERT IGNORE INTO {$wpdb->wc_product_meta_lookup} (`product_id`)
		SELECT
			posts.ID
		FROM {$wpdb->posts} posts
		WHERE
			posts.post_type IN ('product', 'product_variation')
		"
	);

	// List of column names in the lookup table we need to populate.
	$columns = array(
		'min_max_price',
		'stock_quantity',
		'sku',
		'global_unique_id',
		'stock_status',
		'average_rating',
		'total_sales',
		'downloadable',
		'virtual',
		'onsale',
		'tax_class',
		'tax_status', // When last column is updated, woocommerce_product_lookup_table_is_generating is updated.
	);

	foreach ( $columns as $index => $column ) {
		if ( 'average_rating' === $column && ! $reviews_enabled ) {
			continue;
		}

		if ( $is_cli ) {
			wc_update_product_lookup_tables_column( $column );
		} else {
			WC()->queue()->schedule_single(
				time() + $index,
				'wc_update_product_lookup_tables_column',
				array(
					'column' => $column,
				),
				'wc_update_product_lookup_tables'
			);
		}
	}

	if ( ! $reviews_enabled ) {
		return;
	}

	// Rating counts are serialised so they have to be unserialised before populating the lookup table.
	if ( $is_cli ) {
		$rating_count_rows = $wpdb->get_results(
			"
			SELECT post_id, meta_value FROM {$wpdb->postmeta}
			WHERE meta_key = '_wc_rating_count'
			AND meta_value != ''
			AND meta_value != 'a:0:{}'
			",
			ARRAY_A
		);
		wc_update_product_lookup_tables_rating_count( $rating_count_rows );
	} else {
		WC()->queue()->schedule_single(
			time() + 10,
			'wc_update_product_lookup_tables_rating_count_batch',
			array(
				'offset' => 0,
				'limit'  => 50,
			),
			'wc_update_product_lookup_tables'
		);
	}
}

/**
 * Populate lookup table column data.
 *
 * @since 3.6.0
 * @param string $column Column name to set.
 */
function wc_update_product_lookup_tables_column( $column ) {
	if ( empty( $column ) ) {
		return;
	}

	if ( 'average_rating' === $column && ! wc_reviews_enabled() ) {
		return;
	}

	global $wpdb;
	switch ( $column ) {
		case 'min_max_price':
			$wpdb->query(
				"
				UPDATE
					{$wpdb->wc_product_meta_lookup} lookup_table
					INNER JOIN (
						SELECT lookup_table.product_id, MIN( meta_value+0 ) as min_price, MAX( meta_value+0 ) as max_price
						FROM {$wpdb->wc_product_meta_lookup} lookup_table
						LEFT JOIN {$wpdb->postmeta} meta1 ON lookup_table.product_id = meta1.post_id AND meta1.meta_key = '_price'
						WHERE
							meta1.meta_value <> ''
						GROUP BY lookup_table.product_id
					) as source on source.product_id = lookup_table.product_id
				SET
					lookup_table.min_price = source.min_price,
					lookup_table.max_price = source.max_price
				"
			);
			break;
		case 'stock_quantity':
			$wpdb->query(
				"
				UPDATE
					{$wpdb->wc_product_meta_lookup} lookup_table
					LEFT JOIN {$wpdb->postmeta} meta1 ON lookup_table.product_id = meta1.post_id AND meta1.meta_key = '_manage_stock'
					LEFT JOIN {$wpdb->postmeta} meta2 ON lookup_table.product_id = meta2.post_id AND meta2.meta_key = '_stock'
				SET
					lookup_table.stock_quantity = meta2.meta_value
				WHERE
					meta1.meta_value = 'yes'
				"
			);
			break;
		case 'sku':
		case 'global_unique_id':
		case 'stock_status':
		case 'average_rating':
		case 'total_sales':
		case 'tax_class':
		case 'tax_status':
			if ( 'total_sales' === $column ) {
				$meta_key = 'total_sales';
			} elseif ( 'average_rating' === $column ) {
				$meta_key = '_wc_average_rating';
			} else {
				$meta_key = '_' . $column;
			}
			$column = esc_sql( $column );
			// phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared
			$wpdb->query(
				$wpdb->prepare(
					"
					UPDATE
						{$wpdb->wc_product_meta_lookup} lookup_table
						LEFT JOIN {$wpdb->postmeta} meta ON lookup_table.product_id = meta.post_id AND meta.meta_key = %s
					SET
						lookup_table.`{$column}` = meta.meta_value
					",
					$meta_key
				)
			);
			// phpcs:enable WordPress.DB.PreparedSQL.InterpolatedNotPrepared
			break;
		case 'downloadable':
		case 'virtual':
			$column   = esc_sql( $column );
			$meta_key = '_' . $column;
			// phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared
			$wpdb->query(
				$wpdb->prepare(
					"
					UPDATE
						{$wpdb->wc_product_meta_lookup} lookup_table
						LEFT JOIN {$wpdb->postmeta} meta1 ON lookup_table.product_id = meta1.post_id AND meta1.meta_key = %s
					SET
						lookup_table.`{$column}` = IF ( meta1.meta_value = 'yes', 1, 0 )
					",
					$meta_key
				)
			);
			// phpcs:enable WordPress.DB.PreparedSQL.InterpolatedNotPrepared
			break;
		case 'onsale':
			$column   = esc_sql( $column );
			$decimals = absint( wc_get_price_decimals() );

			// phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared
			$wpdb->query(
				$wpdb->prepare(
					"
					UPDATE
						{$wpdb->wc_product_meta_lookup} lookup_table
						LEFT JOIN {$wpdb->postmeta} meta1 ON lookup_table.product_id = meta1.post_id AND meta1.meta_key = '_price'
						LEFT JOIN {$wpdb->postmeta} meta2 ON lookup_table.product_id = meta2.post_id AND meta2.meta_key = '_sale_price'
	  					LEFT JOIN {$wpdb->postmeta} meta3 ON lookup_table.product_id = meta3.post_id AND meta3.meta_key = '_regular_price'
					SET
						lookup_table.`{$column}` = IF (
							CAST( meta1.meta_value AS DECIMAL ) >= 0
							AND CAST( meta2.meta_value AS CHAR ) != ''
							AND CAST( meta1.meta_value AS DECIMAL( 10, %d ) ) = CAST( meta2.meta_value AS DECIMAL( 10, %d ) )
							AND CAST( meta3.meta_value AS DECIMAL( 10, %d ) ) > CAST( meta2.meta_value AS DECIMAL( 10, %d ) )
						, 1, 0 )
					",
					$decimals,
					$decimals,
					$decimals,
					$decimals
				)
			);
			// phpcs:enable WordPress.DB.PreparedSQL.InterpolatedNotPrepared
			break;
	}

	// Final column - mark complete.
	if ( 'tax_status' === $column ) {
		delete_option( 'woocommerce_product_lookup_table_is_generating' );
	}
}
add_action( 'wc_update_product_lookup_tables_column', 'wc_update_product_lookup_tables_column' );

/**
 * Populate rating count lookup table data for products.
 *
 * @since 3.6.0
 * @param array $rows Rows of rating counts to update in lookup table.
 */
function wc_update_product_lookup_tables_rating_count( $rows ) {
	if ( ! $rows || ! is_array( $rows ) ) {
		return;
	}
	global $wpdb;

	foreach ( $rows as $row ) {
		$count = array_sum( (array) maybe_unserialize( $row['meta_value'] ) );
		$wpdb->update(
			$wpdb->wc_product_meta_lookup,
			array(
				'rating_count' => absint( $count ),
			),
			array(
				'product_id' => absint( $row['post_id'] ),
			)
		);
	}
}

/**
 * Populate a batch of rating count lookup table data for products.
 *
 * @since 3.6.2
 * @param array $offset Offset to query.
 * @param array $limit  Limit to query.
 */
function wc_update_product_lookup_tables_rating_count_batch( $offset = 0, $limit = 0 ) {
	global $wpdb;

	if ( ! $limit || ! wc_reviews_enabled() ) {
		return;
	}

	$rating_count_rows = $wpdb->get_results(
		$wpdb->prepare(
			"
			SELECT post_id, meta_value FROM {$wpdb->postmeta}
			WHERE meta_key = '_wc_rating_count'
			AND meta_value != ''
			AND meta_value != 'a:0:{}'
			ORDER BY post_id ASC
			LIMIT %d, %d
			",
			$offset,
			$limit
		),
		ARRAY_A
	);

	if ( $rating_count_rows ) {
		wc_update_product_lookup_tables_rating_count( $rating_count_rows );
		WC()->queue()->schedule_single(
			time() + 1,
			'wc_update_product_lookup_tables_rating_count_batch',
			array(
				'offset' => $offset + $limit,
				'limit'  => $limit,
			),
			'wc_update_product_lookup_tables'
		);
	}
}
add_action( 'wc_update_product_lookup_tables_rating_count_batch', 'wc_update_product_lookup_tables_rating_count_batch', 10, 2 );

/**
 * Attach product featured image. Use image filename to match a product sku when product is not provided.
 *
 * @since 8.5.0
 * @param int        $attachment_id Media attachment ID.
 * @param WC_Product $product Optional product object.
 * @param bool       $save_product If true, the changes in the product will be saved before the method returns.
 * @return void
 */
function wc_product_attach_featured_image( $attachment_id, $product = null, $save_product = true ) {
	$attachment_post = get_post( $attachment_id );
	if ( ! $attachment_post ) {
		return;
	}

	if ( null === $product && wc_get_container()->get( MatchImageBySKU::class )->is_enabled() ) {
		// On upload the attachment post title is the uploaded file's filename.
		$file_name = pathinfo( $attachment_post->post_title, PATHINFO_FILENAME );
		if ( ! $file_name ) {
			return;
		}

		$product_id = wc_get_product_id_by_sku( $file_name );
		$product    = wc_get_product( $product_id );
	}

	if ( ! $product || ! current_user_can( 'edit_product', $product->get_id() ) ) {
		return;
	}

	$product->set_image_id( $attachment_id );
	if ( $save_product ) {
		$product->save();
	}
	if ( 0 === $attachment_post->post_parent ) {
		wp_update_post(
			array(
				'ID'          => $attachment_id,
				'post_parent' => $product->get_id(),
			)
		);
	}
}
add_action( 'add_attachment', 'wc_product_attach_featured_image' );
r_id );
	$trigger_reduce = apply_filters( 'woocommerce_payment_complete_reduce_order_stock', ! $stock_reduced, $order_id );

	// Only continue if we're reducing stock.
	if ( ! $trigger_reduce ) {
		return;
	}

	wc_reduce_stock_levels( $order );

	// Ensure stock is marked as "reduced" in case payment complete or other stock actions are called.
	$order->get_data_store()->set_stock_reduced( $order_id, true );
}
add_action( 'woocommerce_payment_complete', 'wc_maybe_reduce_stock_levels' );
add_action( 'woocommerce_order_status_completed', 'wc_maybe_reduce_stock_levels' );
add_action( 'woocommerce_order_status_processing', 'wc_maybe_reduce_stock_levels' );
add_action( 'woocommerce_order_status_on-hold', 'wc_maybe_reduce_stock_levels' );

/**
 * Restore stock for an order that reduced it, when it moves to a status that releases stock
 * (cancelled, pending, or failed).
 *
 * @since 3.0.0
 * @param int $order_id Order ID.
 */
function wc_maybe_increase_stock_levels( $order_id ) {
	$order = wc_get_order( $order_id );

	if ( ! $order ) {
		return;
	}

	$stock_reduced    = $order->get_data_store()->get_stock_reduced( $order_id );
	$trigger_increase = (bool) $stock_reduced;

	// Only continue if we're increasing stock.
	if ( ! $trigger_increase ) {
		return;
	}

	wc_increase_stock_levels( $order );

	// Ensure stock is not marked as "reduced" anymore.
	$order->get_data_store()->set_stock_reduced( $order_id, false );
}
add_action( 'woocommerce_order_status_cancelled', 'wc_maybe_increase_stock_levels' );
add_action( 'woocommerce_order_status_pending', 'wc_maybe_increase_stock_levels' );
// Restore stock when a stock-reduced order fails. wc_maybe_increase_stock_levels() only acts when
// the order carries the `_order_stock_reduced` flag, so it restores an order that reduced stock
// (in practice one left on-hold by an async payment such as SEPA/ACH) and does nothing for a
// pending -> failed decline that never reduced. Added in 11.0.0.
add_action( 'woocommerce_order_status_failed', 'wc_maybe_increase_stock_levels' );

/**
 * Reduce stock levels for items within an order, if stock has not already been reduced for the items.
 *
 * @since 3.0.0
 * @param int|WC_Order $order_id Order ID or order instance.
 */
function wc_reduce_stock_levels( $order_id ) {
	if ( is_a( $order_id, 'WC_Order' ) ) {
		$order    = $order_id;
		$order_id = $order->get_id();
	} else {
		$order = wc_get_order( $order_id );
	}
	// We need an order, and a store with stock management to continue.
	if ( ! $order || 'yes' !== get_option( 'woocommerce_manage_stock' ) || ! apply_filters( 'woocommerce_can_reduce_order_stock', true, $order ) ) {
		return;
	}

	$changes = array();

	// Loop over all items.
	foreach ( $order->get_items() as $item ) {
		if ( ! $item->is_type( 'line_item' ) ) {
			continue;
		}

		// Only reduce stock once for each item.
		$product            = $item->get_product();
		$item_stock_reduced = $item->get_meta( '_reduced_stock', true );

		if ( $item_stock_reduced || ! $product || ! $product->managing_stock() ) {
			continue;
		}

		/**
		 * Filter order item quantity.
		 *
		 * @param int|float             $quantity Quantity.
		 * @param WC_Order              $order    Order data.
		 * @param WC_Order_Item_Product $item Order item data.
		 */
		$qty       = apply_filters( 'woocommerce_order_item_quantity', $item->get_quantity(), $order, $item );
		$item_name = $product->get_name();
		$new_stock = wc_update_product_stock( $product, $qty, 'decrease' );

		if ( is_wp_error( $new_stock ) ) {
			/* translators: %s item name. */
			$order->add_order_note( sprintf( __( 'Unable to reduce stock for item %s.', 'woocommerce' ), $item_name ), false, false, array( 'note_group' => OrderNoteGroup::ERROR ) );
			continue;
		}

		$item->add_meta_data( '_reduced_stock', $qty, true );
		$item->save();

		$change    = array(
			'product' => $product,
			'from'    => $new_stock + $qty,
			'to'      => $new_stock,
		);
		$changes[] = $change;

		/**
		 * Fires when stock reduced to a specific line item
		 *
		 * @param WC_Order_Item_Product $item Order item data.
		 * @param array $change  Change Details.
		 * @param WC_Order $order  Order data.
		 * @since 7.6.0
		 */
		do_action( 'woocommerce_reduce_order_item_stock', $item, $change, $order );
	}

	wc_trigger_stock_change_notifications( $order, $changes );

	do_action( 'woocommerce_reduce_order_stock', $order );
}

/**
 * After stock change events, triggers emails and adds order notes.
 *
 * @since 3.5.0
 * @param WC_Order $order order object.
 * @param array    $changes Array of changes.
 */
function wc_trigger_stock_change_notifications( $order, $changes ) {
	if ( empty( $changes ) ) {
		return;
	}

	$order_notes     = array();
	$no_stock_amount = absint( get_option( 'woocommerce_notify_no_stock_amount', 0 ) );

	foreach ( $changes as $change ) {
		$order_notes[]    = $change['product']->get_name() . ' (' . $change['from'] . '&rarr;' . $change['to'] . ')';
		$low_stock_amount = absint( wc_get_low_stock_amount( wc_get_product( $change['product']->get_id() ) ) );
		if ( $change['to'] <= $no_stock_amount ) {
			/**
			 * Action to signal that the value of 'stock_quantity' for a variation is about to change.
			 *
			 * @since 4.9
			 *
			 * @param int $product The variation whose stock is about to change.
			 */
			do_action( 'woocommerce_no_stock', wc_get_product( $change['product']->get_id() ) );
		} elseif ( $change['to'] <= $low_stock_amount ) {
			/**
			 * Action to signal that the value of 'stock_quantity' for a product is about to change.
			 *
			 * @since 4.9
			 *
			 * @param int $product The product whose stock is about to change.
			 */
			do_action( 'woocommerce_low_stock', wc_get_product( $change['product']->get_id() ) );
		}

		if ( $change['to'] < 0 ) {
			/**
			 * Action fires when an item in an order is backordered.
			 *
			 * @since 3.0
			 *
			 * @param array $args {
			 *     @type WC_Product $product  The product that is on backorder.
			 *     @type int        $order_id The ID of the order.
			 *     @type int|float  $quantity The amount of product on backorder.
			 * }
			 */
			do_action(
				'woocommerce_product_on_backorder',
				array(
					'product'  => wc_get_product( $change['product']->get_id() ),
					'order_id' => $order->get_id(),
					'quantity' => abs( $change['from'] - $change['to'] ),
				)
			);
		}
	}

	$order->add_order_note( __( 'Stock levels reduced:', 'woocommerce' ) . ' ' . implode( ', ', $order_notes ), false, false, array( 'note_group' => OrderNoteGroup::PRODUCT_STOCK ) );
}

/**
 * Check if a product's stock quantity has reached certain thresholds and trigger appropriate actions.
 *
 * This functionality was moved out of `wc_trigger_stock_change_notifications` in order to decouple it from orders,
 * since stock quantity can also be updated in other ways.
 *
 * @param WC_Product $product        The product whose stock level has changed.
 *
 * @return void
 */
function wc_trigger_stock_change_actions( $product ) {
	if ( true !== $product->get_manage_stock() ) {
		return;
	}

	$no_stock_amount  = absint( get_option( 'woocommerce_notify_no_stock_amount', 0 ) );
	$low_stock_amount = absint( wc_get_low_stock_amount( $product ) );
	$stock_quantity   = $product->get_stock_quantity();

	if ( $stock_quantity <= $no_stock_amount ) {
		/**
		 * Action fires when a product's stock quantity reaches the "no stock" threshold.
		 *
		 * @since 3.0
		 *
		 * @param WC_Product $product The product whose stock quantity has changed.
		 */
		do_action( 'woocommerce_no_stock', $product );
	} elseif ( $stock_quantity <= $low_stock_amount ) {
		/**
		 * Action fires when a product's stock quantity reaches the "low stock" threshold.
		 *
		 * @since 3.0
		 *
		 * @param WC_Product $product The product whose stock quantity has changed.
		 */
		do_action( 'woocommerce_low_stock', $product );
	}
}

/**
 * Increase stock levels for items within an order.
 *
 * @since 3.0.0
 * @param int|WC_Order $order_id Order ID or order instance.
 */
function wc_increase_stock_levels( $order_id ) {
	if ( is_a( $order_id, 'WC_Order' ) ) {
		$order    = $order_id;
		$order_id = $order->get_id();
	} else {
		$order = wc_get_order( $order_id );
	}

	// We need an order, and a store with stock management to continue.
	if ( ! $order || 'yes' !== get_option( 'woocommerce_manage_stock' ) || ! apply_filters( 'woocommerce_can_restore_order_stock', true, $order ) ) {
		return;
	}

	$changes = array();

	// Loop over all items.
	foreach ( $order->get_items() as $item ) {
		if ( ! $item->is_type( 'line_item' ) ) {
			continue;
		}

		// Only increase stock once for each item.
		$product            = $item->get_product();
		$item_stock_reduced = $item->get_meta( '_reduced_stock', true );

		if ( ! $item_stock_reduced || ! $product || ! $product->managing_stock() ) {
			continue;
		}

		$item_name = $product->get_name();
		$new_stock = wc_update_product_stock( $product, $item_stock_reduced, 'increase' );
		$old_stock = $new_stock - $item_stock_reduced;

		if ( is_wp_error( $new_stock ) ) {
			/* translators: %s item name. */
			$order->add_order_note( sprintf( __( 'Unable to restore stock for item %s.', 'woocommerce' ), $item_name ), false, false, array( 'note_group' => OrderNoteGroup::ERROR ) );
			continue;
		}

		$item->delete_meta_data( '_reduced_stock' );
		$item->save();

		$changes[] = $item_name . ' (' . $old_stock . '&rarr;' . $new_stock . ')';

		/**
		 * Fires when stock restored to a specific line item
		 *
		 * @since 9.1.0
		 * @param WC_Order_Item_Product $item Order item data.
		 * @param int $new_stock  New stock.
		 * @param int $old_stock Old stock.
		 * @param WC_Order $order  Order data.
		 */
		do_action( 'woocommerce_restore_order_item_stock', $item, $new_stock, $old_stock, $order );
	}

	if ( $changes ) {
		$order->add_order_note( __( 'Stock levels increased:', 'woocommerce' ) . ' ' . implode( ', ', $changes ), false, false, array( 'note_group' => OrderNoteGroup::PRODUCT_STOCK ) );
	}

	do_action( 'woocommerce_restore_order_stock', $order );
}

/**
 * See how much stock is being held in pending orders.
 *
 * @since 3.5.0
 * @param WC_Product $product Product to check.
 * @param integer    $exclude_order_id Order ID to exclude.
 * @return int
 */
function wc_get_held_stock_quantity( WC_Product $product, $exclude_order_id = 0 ) {
	/**
	 * Filter: woocommerce_hold_stock_for_checkout
	 * Allows enable/disable hold stock functionality on checkout.
	 *
	 * @since 4.3.0
	 * @param bool $enabled Default to true if managing stock globally.
	 */
	if ( ! apply_filters( 'woocommerce_hold_stock_for_checkout', wc_string_to_bool( get_option( 'woocommerce_manage_stock', 'yes' ) ) ) ) {
		return 0;
	}

	$reserve_stock = new ReserveStock();
	return $reserve_stock->get_reserved_stock( $product, $exclude_order_id );
}

/**
 * Hold stock for an order.
 *
 * @throws ReserveStockException If reserve stock fails.
 *
 * @since 4.1.0
 * @param \WC_Order|int $order Order ID or instance.
 */
function wc_reserve_stock_for_order( $order ) {
	/**
	 * Filter: woocommerce_hold_stock_for_checkout
	 * Allows enable/disable hold stock functionality on checkout.
	 *
	 * @since @since 4.1.0
	 * @param bool $enabled Default to true if managing stock globally.
	 */
	if ( ! apply_filters( 'woocommerce_hold_stock_for_checkout', wc_string_to_bool( get_option( 'woocommerce_manage_stock', 'yes' ) ) ) ) {
		return;
	}

	$order = $order instanceof WC_Order ? $order : wc_get_order( $order );

	if ( $order ) {
		$reserve_stock = new ReserveStock();
		$reserve_stock->reserve_stock_for_order( $order, (int) get_option( 'woocommerce_hold_stock_minutes', 60 ) );
	}
}
add_action( 'woocommerce_checkout_order_created', 'wc_reserve_stock_for_order' );

/**
 * Release held stock for an order.
 *
 * @since 4.3.0
 * @param \WC_Order|int $order Order ID or instance.
 */
function wc_release_stock_for_order( $order ) {
	/**
	 * Filter: woocommerce_hold_stock_for_checkout
	 * Allows enable/disable hold stock functionality on checkout.
	 *
	 * @since 4.3.0
	 * @param bool $enabled Default to true if managing stock globally.
	 */
	if ( ! apply_filters( 'woocommerce_hold_stock_for_checkout', wc_string_to_bool( get_option( 'woocommerce_manage_stock', 'yes' ) ) ) ) {
		return;
	}

	$order = $order instanceof WC_Order ? $order : wc_get_order( $order );

	if ( $order ) {
		$reserve_stock = new ReserveStock();
		$reserve_stock->release_stock_for_order( $order );
	}
}
add_action( 'woocommerce_checkout_order_exception', 'wc_release_stock_for_order' );
add_action( 'woocommerce_payment_complete', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_cancelled', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_completed', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_processing', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_on-hold', 'wc_release_stock_for_order', 11 );

/**
 * Release coupons used for another order.
 *
 * @since 9.5.2
 * @param \WC_Order|int $order Order ID or instance.
 * @param bool          $save Save the order after releasing coupons.
 */
function wc_release_coupons_for_order( $order, bool $save = true ) {
	$order = $order instanceof WC_Order ? $order : wc_get_order( $order );

	if ( $order ) {
		$order->get_data_store()->release_held_coupons( $order, $save );
	}
}

/**
 * Return low stock amount to determine if notification needs to be sent
 *
 * Since 5.2.0, this function no longer redirects from variation to its parent product.
 * Low stock amount can now be attached to the variation itself and if it isn't, only
 * then we check the parent product, and if it's not there, then we take the default
 * from the store-wide setting.
 *
 * @param  WC_Product $product Product to get data from.
 * @since  3.5.0
 * @return int
 */
function wc_get_low_stock_amount( WC_Product $product ) {
	$low_stock_amount = $product->get_low_stock_amount();

	if ( '' === $low_stock_amount && $product->is_type( ProductType::VARIATION ) ) {
		$parent = wc_get_product( $product->get_parent_id() );
		if ( $parent ) {
			$low_stock_amount = $parent->get_low_stock_amount();
		}
	}

	if ( '' === $low_stock_amount ) {
		$low_stock_amount = get_option( 'woocommerce_notify_low_stock_amount', 2 );
	}

	return (int) $low_stock_amount;
}