/** Directives for one cache audience (browser or CDN). Whole seconds. */
interface CacheDirectives {
    maxAge?: number;
    staleWhileRevalidate?: number;
    staleIfError?: number;
    sMaxage?: number;
    noStore?: boolean;
    noCache?: boolean;
    private?: boolean;
    mustRevalidate?: boolean;
    immutable?: boolean;
}
/** Which CDN header name carries the CDN directives. */
type CdnProfile = 'cloudflare' | 'generic' | 'fastly';
interface CacheHeaderInput {
    browser?: CacheDirectives;
    cdn?: CacheDirectives;
    profile?: CdnProfile;
    tags?: string[];
}
type CacheHeaderErrorCode = 'cdn_smaxage_with_stale_while_revalidate' | 'private_browser_with_cdn' | 'invalid_cache_tag' | 'too_many_cache_tags' | 'cache_tags_too_long' | 'invalid_cache_directive' | 'invalid_cdn_profile';
declare class CacheHeaderError extends Error {
    readonly code: CacheHeaderErrorCode;
    readonly details: Record<string, unknown>;
    constructor(code: CacheHeaderErrorCode, message: string, details?: Record<string, unknown>);
}
declare function cacheHeaders(input: CacheHeaderInput): Record<string, string>;
declare function etagFrom(hash: string, opts?: {
    weak?: boolean;
}): string;
declare function notModified(ifNoneMatch: string | null, etag: string): boolean;

export { type CacheDirectives, CacheHeaderError, type CacheHeaderErrorCode, type CacheHeaderInput, type CdnProfile, cacheHeaders, etagFrom, notModified };