import type { ConsentConfigSnapshot, ConsentLoggerOptions, ConsentRecord } from './types.js';
/**
 * Reliable, fire-and-forget transport for consent records.
 *
 * - Prefers `navigator.sendBeacon` so a record survives the page navigation
 *   that often follows "Accept all". The body uses a CORS-safelisted
 *   content-type (`text/plain` by default), so the beacon reaches cross-origin
 *   endpoints with no preflight and regardless of server CORS.
 * - If `contentType` is set to a non-safelisted type (e.g. `application/json`),
 *   a cross-origin beacon would need a preflight beacons cannot perform and be
 *   silently dropped, so `auto` falls back to `fetch(..., { keepalive: true })`
 *   for cross-origin endpoints. keepalive fetch survives navigation too.
 * - Always uses `fetch` when custom headers are configured (beacons cannot set
 *   headers). The `transport` option can force `'beacon'` or `'fetch'`.
 * - Buffers failed sends in `localStorage` and retries them on construction
 *   (i.e. the next page load) and after the next successful send.
 *
 * The class is environment-tolerant: it reads `navigator`, `fetch` and
 * `localStorage` lazily and degrades gracefully when any are unavailable.
 */
export declare class ConsentLogger {
    private readonly endpoint;
    private readonly snapshotEndpoint;
    private readonly transport;
    private readonly contentType;
    private readonly headers;
    private readonly includeUserAgent;
    private readonly queueKey;
    private readonly maxQueueSize;
    private readonly snapshotSentKeyPrefix;
    /** Revisions whose snapshot upload is in-flight or already acknowledged. */
    private readonly snapshotInFlight;
    constructor(options: ConsentLoggerOptions);
    /** Send one consent record. Falls back to the offline queue on failure. */
    log(record: ConsentRecord): void;
    /**
     * Upload a banner-config snapshot. Idempotent per revision: the first
     * successful upload for a given revision sets a localStorage flag, and later
     * calls for the same revision become no-ops until the flag is cleared. The
     * server should additionally dedupe on content hash (DSK-OH Rn. 85).
     *
     * Uses fetch only (not sendBeacon) because beacon's boolean return reflects
     * queueing, not delivery — we cannot set the per-revision dedup flag on a
     * value that doesn't represent an actual HTTP acknowledgement.
     */
    logSnapshot(snapshot: ConsentConfigSnapshot): void;
    /** Attempt to resend any queued records (via fetch, so success is confirmed). */
    flush(): Promise<void>;
    private enrich;
    private dispatch;
    private dispatchTo;
    /**
     * True when `url` resolves to a different origin than the current page.
     * Relative URLs and environments without a `location` are treated as
     * same-origin (the conservative default that preserves beacon usage).
     */
    private isCrossOrigin;
    /**
     * True when `contentType`'s essence is CORS-safelisted, so a cross-origin
     * beacon is a "simple request" that needs no preflight. Parameters (e.g.
     * `;charset=UTF-8`) are ignored — only the type/subtype matters.
     */
    private isSafelistedContentType;
    private sendBeacon;
    private dispatchFetch;
    private dispatchFetchTo;
    /**
     * Merge custom headers but always set the configured `content-type`
     * (case-insensitively), so a raw `Content-Type` header in `headers` can't
     * accidentally break ingestion or diverge from the beacon's content-type.
     */
    private buildFetchHeaders;
    private enqueue;
    private readQueue;
    private writeQueue;
    private isOffline;
}
/** Convenience factory mirroring the `create<Thing>()` style used elsewhere. */
export declare function createConsentLogger(options: ConsentLoggerOptions): ConsentLogger;