import type Cdn from '../Loaders/Cdn';
/**
 * @file First-chunk probe — early abort on cold-start. Mirrors Android
 * `FirstChunkProbeRegistry` + `FirstChunkProbeEventListener` +
 * ActiveSwitcher.evaluateFirstChunkAborts (plugin-android@video-balancer-24-2-on-main).
 *
 * For CDNs without EMA or peak history we apply aggressive timeouts and abort
 * the call when the observed throughput cannot meet the deadline. The probe
 * arms ONLY for the very first attempt to that CDN; once a peak is published
 * (PR5) eligibility flips off and subsequent attempts use the normal timers.
 */
export interface FirstChunkProbeSettings {
    enabled: boolean;
    connectTimeoutMs: number;
    totalDownloadTimeoutMs: number;
    safetyFactor: number;
    minSamplesBeforeAbort: number;
    onlyForVideoSegments: boolean;
}
export declare const DEFAULT_FIRST_CHUNK_PROBE_SETTINGS: FirstChunkProbeSettings;
/**
 * Per-call probe data. `expectedSizeBytes` starts at -1 and is filled in by
 * the HEADERS_RECEIVED hook from `Content-Length`. `cancelled` flips once and
 * stays — guards against double-abort.
 */
export interface FirstChunkProbeTag {
    cdn: Cdn;
    startMs: number;
    deadlineMs: number;
    expectedSizeBytes: number;
    cancelled: boolean;
}
/**
 * Map<XMLHttpRequest, FirstChunkProbeTag>. Mirrors Android
 * `FirstChunkProbeRegistry`; the JS side does not strictly need a separate
 * registry (we have direct XHR access) but keeps the data layout aligned for
 * grep-ability and parity.
 */
export declare class FirstChunkProbeRegistry {
    private readonly probes;
    register(xhr: XMLHttpRequest, tag: FirstChunkProbeTag): void;
    get(xhr: XMLHttpRequest): FirstChunkProbeTag | undefined;
    unregister(xhr: XMLHttpRequest): void;
    forEach(fn: (xhr: XMLHttpRequest, tag: FirstChunkProbeTag) => void): void;
    size(): number;
    clear(): void;
}
/**
 * Eligibility for arming a first-chunk probe on this dispatch. Mirrors
 * Android `firstChunkProbeForOrNull` (ProviderLoader.kt:572):
 *   - settings.enabled
 *   - settings.totalDownloadTimeoutMs > 0
 *   - !settings.onlyForVideoSegments OR url is a video segment
 *   - cdn has neither EMA nor peak bandwidth history (cold-start only)
 */
export declare function isEligibleForFirstChunkProbe(cdn: Cdn, pathname: string, settings: FirstChunkProbeSettings): boolean;