ption( 'woocommerce_attribute_lookup_regeneration_aborted', 'yes' );
	}

	/**
	 * Remove the flag indicating that the last lookup table regeneration process started was aborted.
	 */
	public function unset_regeneration_aborted_flag() {
		delete_option( 'woocommerce_attribute_lookup_regeneration_aborted' );
	}

	/**
	 * Tells if the last lookup table regeneration process started was aborted
	 * (via deleting the 'woocommerce_attribute_lookup_regeneration_in_progress' option).
	 *
	 * @return bool True if the last lookup table regeneration process was aborted.
	 */
	public function regeneration_was_aborted(): bool {
		return get_option( 'woocommerce_attribute_lookup_regeneration_aborted' ) === 'yes';
	}

	/**
	 * Check if the lookup table contains any entry at all.
	 *
	 * @return bool True if the table contains entries, false if the table is empty.
	 */
	public function lookup_table_has_data(): bool {
		global $wpdb;

		// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
		return ( (int) $wpdb->get_var( "SELECT EXISTS (SELECT 1 FROM {$this->lookup_table_name})" ) ) !== 0;
	}

	/**
	 * Handler for 'woocommerce_get_sections_products', adds the "Advanced" section to the product settings.
	 *
	 * @param array $products Original array of settings sections.
	 * @return array New array of settings sections.
	 */
	private function add_advanced_section_to_product_settings( array $products ): array {
		if ( $this->check_lookup_table_exists() ) {
			$products['advanced'] = __( 'Advanced', 'woocommerce' );
		}

		return $products;
	}

	/**
	 * Handler for 'woocommerce_get_settings_products', adds the settings related to the product attributes lookup table.
	 *
	 * @param array  $settings Original settings configuration array.
	 * @param string $section_id Settings section identifier.
	 * @return array New settings configuration array.
	 */
	private function add_product_attributes_lookup_table_settings( array $settings, string $section_id ): array {
		if ( $section_id === 'advanced' && $this->check_lookup_table_exists() ) {
			$title_item = array(
				'title' => __( 'Product attributes lookup table', 'woocommerce' ),
				'type'  => 'title',
			);

			$regeneration_is_in_progress = $this->regeneration_is_in_progress();

			if ( $regeneration_is_in_progress ) {
				$title_item['desc'] = __( 'These settings are not available while the lookup table regeneration is in progress.', 'woocommerce' );
			}

			$settings[] = $title_item;

			if ( ! $regeneration_is_in_progress ) {
				$regeneration_aborted_warning =
					$this->regeneration_was_aborted() ?
						sprintf(
							"<p><strong style='color: #E00000'>%s</strong></p><p>%s</p>",
							__( 'WARNING: The product attributes lookup table regeneration process was aborted.', 'woocommerce' ),
							__( 'This means that the table is probably in an inconsistent state. It\'s recommended to run a new regeneration process or to resume the aborted process (Status - Tools - Regenerate the product attributes lookup table/Resume the product attributes lookup table regeneration) before enabling the table usage.', 'woocommerce' )
						) : null;

				$settings[] = array(
					'title'         => __( 'Enable table usage', 'woocommerce' ),
					'desc'          => __( 'Use the product attributes lookup table for catalog filtering.', 'woocommerce' ),
					'desc_tip'      => $regeneration_aborted_warning,
					'id'            => 'woocommerce_attribute_lookup_enabled',
					'default'       => 'no',
					'type'          => 'checkbox',
					'checkboxgroup' => 'start',
				);

				$settings[] = array(
					'title'         => __( 'Direct updates', 'woocommerce' ),
					'desc'          => __( 'Update the table directly upon product changes, instead of scheduling a deferred update.', 'woocommerce' ),
					'id'            => 'woocommerce_attribute_lookup_direct_updates',
					'default'       => 'no',
					'type'          => 'checkbox',
					'checkboxgroup' => 'start',
				);
			}

			$settings[] = array( 'type' => 'sectionend' );
		}

		return $settings;
	}
}