regeneration is already in progress.
	 */
	private function initiate_regeneration_from_tools_page() {
		$this->verify_tool_execution_nonce();

		//phpcs:disable WordPress.Security.NonceVerification.Recommended
		if ( isset( $_REQUEST['regenerate_product_attribute_lookup_data_product_id'] ) ) {
			$product_id = (int) $_REQUEST['regenerate_product_attribute_lookup_data_product_id'];
			$this->check_can_do_lookup_table_regeneration( $product_id );
			$this->data_store->create_data_for_product( $product_id );
		} else {
			$this->check_can_do_lookup_table_regeneration();
			$this->initiate_regeneration();
		}
		//phpcs:enable WordPress.Security.NonceVerification.Recommended
	}

	/**
	 * Enable or disable the actual lookup table usage.
	 *
	 * @param bool $enable True to enable, false to disable.
	 * @throws \Exception A lookup table regeneration is currently in progress.
	 */
	private function enable_or_disable_lookup_table_usage( $enable ) {
		if ( $this->data_store->regeneration_is_in_progress() ) {
			throw new \Exception( "Can't enable or disable the attributes lookup table usage while it's regenerating." );
		}

		update_option( 'woocommerce_attribute_lookup_enabled', $enable ? 'yes' : 'no' );
	}

	/**
	 * Check if everything is good to go to perform a complete or per product lookup table data regeneration
	 * and throw an exception if not.
	 *
	 * @param mixed $product_id The product id to check the regeneration viability for, or null to check if a complete regeneration is possible.
	 * @throws \Exception Something prevents the regeneration from starting.
	 */
	private function check_can_do_lookup_table_regeneration( $product_id = null ) {
		if ( $product_id && ! $this->data_store->check_lookup_table_exists() ) {
			throw new \Exception( "Can't do product attribute lookup data regeneration: lookup table doesn't exist" );
		}
		if ( $this->data_store->regeneration_is_in_progress() ) {
			throw new \Exception( "Can't do product attribute lookup data regeneration: regeneration is already in progress" );
		}
		if ( $product_id && ! wc_get_product( $product_id ) ) {
			throw new \Exception( "Can't do product attribute lookup data regeneration: product doesn't exist" );
		}
	}

	/**
	 * Callback to abort the regeneration process from the Status - Tools page.
	 *
	 * @throws \Exception The lookup table doesn't exist, or there's no regeneration process in progress to abort.
	 */
	private function abort_regeneration_from_tools_page() {
		$this->verify_tool_execution_nonce();

		if ( ! $this->data_store->check_lookup_table_exists() ) {
			throw new \Exception( "Can't abort the product attribute lookup data regeneration process: lookup table doesn't exist" );
		}
		if ( ! $this->data_store->regeneration_is_in_progress() ) {
			throw new \Exception( "Can't abort the product attribute lookup data regeneration process since it's not currently in progress" );
		}

		$queue = WC()->get_instance_of( \WC_Queue::class );
		$queue->cancel_all( 'woocommerce_run_product_attribute_lookup_regeneration_callback' );
		$this->data_store->unset_regeneration_in_progress_flag();
		$this->data_store->set_regeneration_aborted_flag();
		$this->enable_or_disable_lookup_table_usage( false );

		// Note that we are NOT deleting the options that track the regeneration progress (processed count, last product id to process).
		// This is on purpose so that the regeneration can be resumed where it stopped.
	}

	/**
	 * Callback to resume the regeneration process from the Status - Tools page.
	 *
	 * @throws \Exception The lookup table doesn't exist, or a regeneration process is already in place.
	 */
	private function resume_regeneration_from_tools_page() {
		$this->verify_tool_execution_nonce();

		if ( ! $this->data_store->check_lookup_table_exists() ) {
			throw new \Exception( "Can't resume the product attribute lookup data regeneration process: lookup table doesn't exist" );
		}
		if ( $this->data_store->regeneration_is_in_progress() ) {
			throw new \Exception( "Can't resume the product attribute lookup data regeneration process: regeneration is already in progress" );
		}

		$this->data_store->unset_regeneration_aborted_flag();
		$this->data_store->set_regeneration_in_progress_flag();
		$this->enqueue_regeneration_step_run();
	}

	/**
	 * Verify the validity of the nonce received when executing a tool from the Status - Tools page.
	 *
	 * @throws \Exception Missing or invalid nonce received.
	 */
	private function verify_tool_execution_nonce() {
		// phpcs:ignore WordPress.Security.ValidatedSanitizedInput
		if ( ! isset( $_REQUEST['_wpnonce'] ) || wp_verify_nonce( $_REQUEST['_wpnonce'], 'debug_action' ) === false ) {
			throw new \Exception( 'Invalid nonce' );
		}
	}

	/**
	 * Get the name of the product attributes lookup table.
	 *
	 * @return string
	 */
	public function get_lookup_table_name() {
		return $this->lookup_table_name;
	}

	/**
	 * Get the SQL statement that creates the product attributes lookup table, including the indices.
	 *
	 * @return string
	 */
	public function get_table_creation_sql() {
		global $wpdb;

		$collate = $wpdb->has_cap( 'collation' ) ? $wpdb->get_charset_collate() : '';

		return "CREATE TABLE {$this->lookup_table_name} (
 product_id bigint(20) NOT NULL,
 product_or_parent_id bigint(20) NOT NULL,
 taxonomy varchar(32) NOT NULL,
 term_id bigint(20) NOT NULL,
 is_variation_attribute tinyint(1) NOT NULL,
 in_stock tinyint(1) NOT NULL,
 INDEX is_variation_attribute_term_id (is_variation_attribute, term_id),
 PRIMARY KEY  ( `product_or_parent_id`, `term_id`, `product_id`, `taxonomy` )
) $collate;";
	}

	/**
	 * Create the primary key for the table if it doesn't exist already.
	 * It also deletes the product_or_parent_id_term_id index if it exists, since it's now redundant.
	 *
	 * @return void
	 */
	public function create_table_primary_index() {
		$database_util = wc_get_container()->get( DatabaseUtil::class );
		$database_util->create_primary_key( $this->lookup_table_name, array( 'product_or_parent_id', 'term_id', 'product_id', 'taxonomy' ) );
		$database_util->drop_table_index( $this->lookup_table_name, 'product_or_parent_id_term_id' );

		if ( empty( $database_util->get_index_columns( $this->lookup_table_name ) ) ) {
			wc_get_logger()->error( "The creation of the primary key for the {$this->lookup_table_name} table failed" );
		}

		if ( ! empty( $database_util->get_index_columns( $this->lookup_table_name, 'product_or_parent_id_term_id' ) ) ) {
			wc_get_logger()->error( "Dropping the product_or_parent_id_term_id index from the {$this->lookup_table_name} table failed" );
		}
	}

	/**
	 * Run additional setup needed after a WooCommerce install or update finishes.
	 */
	private function run_woocommerce_installed_callback() {
		// The table must exist at this point (created via dbDelta), but we check just in case.
		if ( ! $this->data_store->check_lookup_table_exists() ) {
			return;
		}

		// If a table regeneration is in progress, leave it alone.
		if ( $this->data_store->regeneration_is_in_progress() ) {
			return;
		}

		// If the lookup table has data, or if it's empty because there are no products yet, we're good.
		// Otherwise (lookup table is empty but products exist) we need to initiate a regeneration if one isn't already in progress.
		if ( $this->data_store->lookup_table_has_data() || ! $this->get_last_existing_product_id() ) {
			$must_enable = get_option( 'woocommerce_attribute_lookup_enabled' ) !== 'no';
			$this->finalize_regeneration( $must_enable );
		} else {
			$this->initiate_regeneration();
		}
	}
}