import { type CapturedTrace, type CapturedTransaction, type HttpParticipantRole } from '@thymian/core';
type HeaderValue = string | string[] | undefined;
export type ForwardingHop = {
    /**
     * Transaction on the user-agent side of the forwarding participant
     * (`trace[i - 1]`): its request is the message the participant received,
     * its response is the message the participant sent back downstream.
     */
    inbound: CapturedTransaction;
    /**
     * Transaction on the origin side of the forwarding participant
     * (`trace[i]`): its request is the message the participant forwarded
     * onward, its response is the message it received from upstream.
     */
    outbound: CapturedTransaction;
};
/**
 * Pairs adjacent transactions of a captured trace into forwarding hops.
 *
 * Captured traces are ordered root-first (see `sortTraceTransactions` in
 * plugin-http-analyzer): `trace[0]` is the transaction observed at the edge,
 * closest to the user agent, and each later entry is the onward transaction
 * produced by the forwarding participant between it and its predecessor.
 * Because `meta.role` names the participant that produced a message, that
 * middle participant is identified by `outbound.request.meta.role` (it sent
 * the onward request) or `inbound.response.meta.role` (it sent the downstream
 * response).
 *
 * Only hops whose middle participant matches one of the given roles are
 * returned; umbrella roles are expanded, so the default `['intermediary']`
 * also matches concrete `proxy`, `gateway` and `tunnel` stamps. Traces with
 * fewer than two transactions (e.g. single-transaction HAR imports) yield no
 * hops.
 */
export declare function forwardingHops(trace: CapturedTrace, roles?: readonly HttpParticipantRole[]): ForwardingHop[];
export declare function headerValues(value: HeaderValue): string[];
/**
 * Splits a comma-separated header value on top-level commas only, ignoring
 * commas inside parenthesised comments. Via entries may carry `(...)` comments
 * that themselves contain commas, so a naive `split(',')` would corrupt the
 * received-by tokens. Nested comments and quoted-pairs (`\)`) are handled.
 */
export declare function splitTopLevelCommas(value: string): string[];
export declare function equalHeaderValues(a: HeaderValue, b: HeaderValue): boolean;
export declare function connectionOptionNames(value: HeaderValue): string[];
export declare function parseMaxForwards(value: HeaderValue): number | undefined;
export {};
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