public function __construct() {
		$default_steps = array(
			'upload'  => array(
				'name'    => __( 'Upload CSV file', 'woocommerce' ),
				'view'    => array( $this, 'upload_form' ),
				'handler' => array( $this, 'upload_form_handler' ),
			),
			'mapping' => array(
				'name'    => __( 'Column mapping', 'woocommerce' ),
				'view'    => array( $this, 'mapping_form' ),
				'handler' => '',
			),
			'import'  => array(
				'name'    => __( 'Import', 'woocommerce' ),
				'view'    => array( $this, 'import' ),
				'handler' => '',
			),
			'done'    => array(
				'name'    => __( 'Done!', 'woocommerce' ),
				'view'    => array( $this, 'done' ),
				'handler' => '',
			),
		);

		$this->steps = apply_filters( 'woocommerce_product_csv_importer_steps', $default_steps );

		// phpcs:disable WordPress.Security.NonceVerification.Recommended
		$this->step            = isset( $_REQUEST['step'] ) ? sanitize_key( $_REQUEST['step'] ) : current( array_keys( $this->steps ) );
		$this->file            = isset( $_REQUEST['file'] ) ? wc_clean( wp_unslash( $_REQUEST['file'] ) ) : '';
		$this->update_existing = isset( $_REQUEST['update_existing'] ) ? (bool) $_REQUEST['update_existing'] : false;
		$this->delimiter       = ! empty( $_REQUEST['delimiter'] ) ? wc_clean( wp_unslash( $_REQUEST['delimiter'] ) ) : ',';
		$this->map_preferences = isset( $_REQUEST['map_preferences'] ) ? (bool) $_REQUEST['map_preferences'] : false;
		// phpcs:enable

		// Import mappings for CSV data.
		include_once dirname( __FILE__ ) . '/mappings/mappings.php';

		if ( $this->map_preferences ) {
			add_filter( 'woocommerce_csv_product_import_mapped_columns', array( $this, 'auto_map_user_preferences' ), 9999 );
		}
	}