/**
 * A Circuit Breaker pattern implementation to prevent cascading failures
 * @class
 * @param {Object} options - Configuration options
 * @param {number} options.failureThreshold - Number of failures before opening the circuit
 * @param {number} options.resetTimeout - Timeout in ms before attempting to reset the circuit
 * @param {string} [options.state='closed'] - Initial state of the circuit breaker
 * @throws {Error} If failureThreshold or resetTimeout is not a positive number
 */
export class CircuitBreaker {
    /**
     * Creates an instance of CircuitBreaker
     * @constructor
     * @param {Object} options - Configuration options
     * @param {number} options.failureThreshold - Number of failures before opening the circuit
     * @param {number} options.resetTimeout - Timeout in ms before attempting to reset the circuit
     * @param {string} [options.state='closed'] - Initial state of the circuit breaker
     * @throws {Error} If failureThreshold or reset,Timeout is not a positive number
     */
    constructor(options: {
        failureThreshold: number;
        resetTimeout: number;
        state?: string;
    });
    failureThreshold: number;
    resetTimeout: number;
    state: string;
    failureCount: number;
    lastFailureTime: number;
    /**
     * Calls the provided function and manages circuit state
     * @param {Function} fn - Function to call
     * @returns {Promise<any>} Result of the function call
     * @throws {Error} If circuit is open or if the function throws an error
     * @example
     * const breaker = new CircuitBreaker({ failureThreshold: 3, resetTimeout: 5000 });
     * const result = await breaker.call(() => fetch('https://api.example.com/data'));
     * console.log(result);
     */
    call(fn: Function): Promise<any>;
    /**
     * Checks if the circuit can be closed based on the reset timeout
     * @returns {boolean} True if circuit can be closed, false otherwise
     */
    canClose(): boolean;
    /**
     * Manually closes the circuit
     * @returns {void}
     */
    close(): void;
    /**
     * Returns the current state of the circuit
     * @returns {string} Current state ('closed', 'open', or 'half-open')
     */
    getState(): string;
    /**
     * Returns the number of failures recorded
     * @returns {number} Failure count
     */
    getFailureCount(): number;
}