/**
 * @file sdp-utils.ts
 * @description SDP generation/parsing for a WebRTC data-channel m-section.
 * @module sdp/sdp-utils
 *
 * Emits the standard application m-line with the SCTP-over-DTLS profile and
 * conveys transport addresses through ICE candidates (not the c=/m= lines, per
 * the WebRTC JSEP/SDP rules). This is what browsers expect.
 */
/** ICE credentials. */
export interface IceCredentials {
    usernameFragment: string;
    password: string;
}
/** DTLS certificate fingerprint. */
export interface Fingerprint {
    algorithm: string;
    value: string;
}
/** A candidate descriptor as accepted by {@link buildSdp}. */
export interface CandidateInput {
    sdp?: string;
    candidate?: string;
}
/** Options accepted by {@link buildSdp}. */
export interface BuildSdpOptions {
    kind?: 'offer' | 'answer';
    iceUfrag: string;
    icePwd: string;
    fingerprint?: Fingerprint;
    setup?: string;
    candidates?: CandidateInput[];
    sctpPort?: number;
    maxMessageSize?: number;
}
/** Options accepted by {@link generateOffer} / {@link generateAnswer}. */
export interface GenerateOptions extends BuildSdpOptions {
}
/** Parsed ICE parameters. */
export interface IceParameters {
    usernameFragment: string | null;
    password: string | null;
}
/** Parsed DTLS parameters. */
export interface DtlsParameters {
    role: string;
    fingerprints: Fingerprint[];
    setup?: string;
}
/** Parsed SCTP parameters. */
export interface SctpParameters {
    port: number;
    maxMessageSize: number;
}
/** A parsed ICE candidate. */
export interface ParsedCandidate {
    candidate: string;
    foundation: string;
    component: number;
    protocol: string;
    priority: number;
    address: string;
    port: number;
    type: string;
}
/**
 * Generate ICE credentials (ufrag >= 4 chars, pwd >= 22 chars per RFC 8445).
 * @returns {{usernameFragment:string, password:string}}
 */
export declare function generateIceCredentials(): IceCredentials;
/**
 * Build the SDP for a data-channel-only session.
 * @param {Object} o
 * @param {'offer'|'answer'} o.kind
 * @param {string} o.iceUfrag
 * @param {string} o.icePwd
 * @param {{algorithm:string,value:string}} o.fingerprint - DTLS cert fingerprint
 * @param {string} o.setup - 'actpass' | 'active' | 'passive'
 * @param {Array<{sdp?:string,candidate?:string}>} [o.candidates]
 * @param {number} [o.sctpPort=5000]
 * @param {number} [o.maxMessageSize=262144]
 * @returns {string}
 */
export declare function buildSdp(o: BuildSdpOptions): string;
export declare function generateOffer(opts: GenerateOptions): string;
export declare function generateAnswer(opts: GenerateOptions): string;
/** Parse ICE ufrag/pwd. */
export declare function parseIceParameters(sdp: string): IceParameters;
/** Parse DTLS setup role + fingerprints. */
export declare function parseDtlsParameters(sdp: string): DtlsParameters;
/** Parse SCTP port / max message size. */
export declare function parseSctpParameters(sdp: string): SctpParameters;
/**
 * Parse ICE candidate lines into structured objects.
 * @param {string} sdp
 * @returns {Array<{candidate:string,foundation:string,component:number,protocol:string,priority:number,address:string,port:number,type:string}>}
 */
export declare function parseCandidates(sdp: string): ParsedCandidate[];
/**
 * Parse a single "candidate:..." string.
 * @param {string} str
 */
export declare function parseCandidateLine(str: string): ParsedCandidate | null;