import { KeyStorageAdapter } from '../core/types';
export declare const DEFAULT_INSTANCE = "default";
/**
 * The database backing an instance's keys.
 *
 * Exported so the rule can be tested directly: if two instances ever resolve to
 * one database they share a keypair, publish the same public key under both user
 * ids, and become linkable, with nothing visible to say so.
 */
export declare function dbNameFor(instanceName?: string): string;
export declare class IndexedDbKeyStorage implements KeyStorageAdapter {
    private readonly fallback;
    private readonly dbName;
    /**
     * Each named instance gets a database of its own. Two identities sharing one
     * database would share one messaging keypair, which publishes the same public
     * key under both user ids and links them to anyone who looks, defeating the
     * point of running a second identity at all.
     *
     * The default instance keeps the original database name, so an app upgrading
     * to a version with named instances keeps the identity it already had.
     */
    constructor(instanceName?: string);
    get(key: string): Promise<string | null>;
    set(key: string, value: string): Promise<void>;
    remove(key: string): Promise<void>;
    private isIndexedDbAvailable;
    private openDb;
}