export interface ArkmeAvatarImagePayload {
    mediaType: string;
    dataBase64: string;
}
export interface ArkmeAvatarImageSnapshot {
    cacheKey: string;
    reference: string;
    value: string;
    expiresAtMillis: number;
}
export type ArkmeAvatarImageListener = (imageDataUrl: string | undefined) => void;
export interface ArkmeAvatarImagePort {
    activateScope(scopeKey: string | undefined): void;
    current(imageRef: string): string | undefined;
    /** The grant may rotate while the account-scoped display identity stays stable. */
    load(imageRef: string, cacheKey?: string): Promise<string>;
    subscribe(imageRef: string, listener: ArkmeAvatarImageListener): () => void;
    revalidateActive(imageRefs?: readonly string[]): Promise<void>;
    snapshot?(scopeKey: string, imageRefs: readonly string[]): ArkmeAvatarImageSnapshot[];
    restore?(scopeKey: string, images: readonly ArkmeAvatarImageSnapshot[]): void;
}
export interface ArkmeAvatarPersistentCache {
    read(scope: string, imageRef: string): Promise<ArkmeAvatarImagePayload | undefined>;
    write(scope: string, imageRef: string, payload: ArkmeAvatarImagePayload): Promise<void>;
}
/** These references identify immutable bytes, unlike mutable profile references. */
export declare function isImmutableAvatarRef(ref: string): boolean;
interface InMemoryArkmeAvatarImageStoreOptions {
    reader: (imageRef: string) => Promise<ArkmeAvatarImagePayload>;
    onLoadFailure?: (failure: {
        imageRef: string;
        scopeKey: string | undefined;
        trigger: 'load' | 'revalidate';
        hasCachedImage: boolean;
        durationMillis: number;
        error: unknown;
    }) => void;
    cachedReader?: (imageRef: string) => Promise<ArkmeAvatarImagePayload | undefined>;
    persistentCache?: ArkmeAvatarPersistentCache;
    now?: () => number;
    ttlMillis?: number;
    jitterMillis?: number | (() => number);
    concurrency?: number;
}
export declare class InMemoryArkmeAvatarImageStore implements ArkmeAvatarImagePort {
    private readonly options;
    private readonly entries;
    private readonly listeners;
    private readonly queue;
    private readonly now;
    private readonly ttlMillis;
    private readonly jitterMillis;
    private readonly concurrency;
    private activeDownloads;
    private activeImmutableReads;
    private activeCacheProbes;
    private generation;
    private scopeKey;
    constructor(options: InMemoryArkmeAvatarImageStoreOptions);
    activateScope(scopeKey: string | undefined): void;
    current(imageRef: string): string | undefined;
    /** Copy already-resolved bytes only. Never turn opening a window into an image download. */
    snapshot(scopeKey: string, imageRefs: readonly string[]): ArkmeAvatarImageSnapshot[];
    restore(scopeKey: string, images: readonly ArkmeAvatarImageSnapshot[]): void;
    load(imageRef: string, cacheKey?: string): Promise<string>;
    subscribe(imageRef: string, listener: ArkmeAvatarImageListener): () => void;
    revalidateActive(imageRefs?: readonly string[]): Promise<void>;
    private loadInternal;
    private pruneCache;
    private schedule;
    private drainQueue;
    private notify;
}
export {};
//# sourceMappingURL=avatar-image-store.d.ts.map