/**
 * Environment-neutral retry/backoff/timeout primitives shared across HTTP-backed batteries.
 *
 * @module @nhtio/adk/lib/utils/retry
 *
 * @remarks
 * These are pure helpers — no DOM, no Node built-ins, only `setTimeout`, `AbortController`, and
 * `AbortSignal`, all of which exist in every target runtime (Node, browser, edge, workers). They
 * are shared (not duplicated) by the OpenAI Chat Completions battery and the OpenAI Embeddings
 * battery so retry behavior stays identical across the bundled batteries. The bundler inlines this
 * module into each consumer, so sharing introduces no build coupling.
 */
/**
 * Minimal backoff configuration shape. Any retry config carrying `baseDelayMs`/`maxDelayMs`
 * satisfies it structurally, so batteries can pass their own richer config objects directly.
 */
export interface BackoffConfig {
    /** Base delay in milliseconds for the first retry; doubles each attempt (default 500). */
    baseDelayMs?: number;
    /** Upper bound in milliseconds on any single backoff delay (default 30_000). */
    maxDelayMs?: number;
}
/**
 * Exponential backoff with a ceiling: `min(baseDelayMs * 2^(attempt-1), maxDelayMs)`.
 *
 * @param attempt - 1-based attempt number.
 * @param cfg - Carries `baseDelayMs` (default 500) and `maxDelayMs` (default 30_000).
 * @returns The (un-jittered) delay in ms.
 */
export declare const computeBackoff: (attempt: number, cfg: BackoffConfig) => number;
/**
 * Abort-aware jittered sleep used for retry backoff.
 *
 * @remarks
 * Resolves (never rejects) the instant `signal` aborts, so an aborted caller does not stay parked
 * in a backoff delay — the caller's retry loop re-checks abort state immediately after and bails.
 * The timer and the abort listener are both torn down on whichever fires first, so nothing leaks.
 *
 * @param ms - Base delay in ms; jittered by ±10%.
 * @param signal - Optional abort signal that short-circuits the sleep.
 */
export declare const sleepWithJitter: (ms: number, signal?: AbortSignal) => Promise<void>;
/**
 * Parses an HTTP `Retry-After` header value (delta-seconds or HTTP-date) into milliseconds.
 *
 * @param raw - The header value.
 * @returns Milliseconds to wait, or `0` when the value cannot be parsed or is in the past.
 */
export declare const parseRetryAfter: (raw: string) => number;
/**
 * Combines several abort signals into one.
 *
 * @remarks
 * Returns the linked signal plus a `dispose` that detaches any listeners the fallback path
 * attached, so repeated links on a long-lived signal (one per retry attempt) do not accumulate
 * listeners. The native `AbortSignal.any` path self-manages its listeners, so `dispose` is a no-op
 * there.
 *
 * @param signals - The signals to combine.
 * @returns The linked signal and a `dispose` to tear down fallback listeners.
 */
export declare const linkAbortSignals: (signals: ReadonlyArray<AbortSignal>) => {
    signal: AbortSignal;
    dispose: () => void;
};