/**
 * CronCreator
 * Builds cron expression strings from structured option objects.
 */
import type { CronOptions, CronTuple } from './types';
/** Builds valid cron expression strings from structured options. */
export declare class CronCreator {
  private static instance?;
  /** Get the CronCreator instance. */
  static getInstance(): CronCreator;
  private constructor();
  /**
   * Create a cron expression string from a cron field tuple.
   *
   * @param tuple - Cron field values in standard order.
   * @returns A valid 5-field cron expression.
   *
   * @example
   * creator.fromTuple( [ '0', '9', '*', '*', 'MON' ] );
   */
  fromTuple(tuple: CronTuple): string;
  /**
   * Create a cron expression string from a partial CronObject.
   *
   * Any omitted fields default to the wildcard (`*`).
   *
   * @param options - Partial cron field values.
   * @returns A valid 5-field cron expression.
   *
   * @example
   * creator.fromObject( {
   *   hour: '9',
   *   minute: '0',
   *   dayOfWeek: 'MON-FRI'
   * } );
   */
  fromObject(options: CronOptions): string;
  /**
   * Create a cron expression string from individual field values.
   *
   * Any omitted fields default to the wildcard (`*`).
   *
   * @param minute - Minute field (0-59).
   * @param hour - Hour field (0-23).
   * @param dayOfMonth - Day of month field (1-31).
   * @param month - Month field (1-12 or JAN-DEC).
   * @param dayOfWeek - Day of week field (0-6 or MON-SUN).
   * @returns A valid 5-field cron expression.
   *
   * @example
   * creator.create( '0', '9', '*', '*', 'MON-FRI' );
   */
  create(minute?: string, hour?: string, dayOfMonth?: string, month?: string, dayOfWeek?: string): string;
}