import type { CircuitStateStore, SharedCircuitState } from './circuit-breaker.js';
export type { CircuitStateStore, SharedCircuitState } from './circuit-breaker.js';
/**
 * Shared circuit state in one process.
 *
 * For several `NexusAI` clients or workers inside one process, and for tests. Across processes use
 * `RedisCircuitStateStore` or the Postgres adapter.
 */
export declare class MemoryCircuitStateStore implements CircuitStateStore {
    private readonly now;
    private readonly states;
    private readonly probes;
    constructor(now?: () => number);
    /** Every provider's shared circuit state. */
    read(): SharedCircuitState[];
    /**
     * Writes a transition, unless a newer one is already stored. Releases the provider's probe claim.
     */
    write(state: SharedCircuitState): void;
    /**
     * Claims the right to probe a provider for `ttlMs`. Resolves true for the claimant, including
     * when it already holds the claim.
     */
    claimProbe(providerName: string, owner: string, ttlMs: number): boolean;
}
/**
 * The Redis commands the circuit store needs, in `ioredis` argument order.
 *
 * Structural, as with the other Redis adapters, so no Redis client becomes a dependency. A client
 * with a different `set` signature, such as `node-redis`, needs a one-line wrapper.
 */
export interface RedisCircuitLikeClient {
    /** Reads every hash field. */
    hgetall(key: string): Promise<Record<string, string> | null> | Record<string, string> | null;
    /** Reads a hash field. */
    hget(key: string, field: string): Promise<string | null> | string | null;
    /** Sets a hash field. */
    hset(key: string, field: string, value: string): Promise<unknown> | unknown;
    /** `SET key value PX ttl NX`, resolving to `'OK'` when the key was set. */
    set(key: string, value: string, px: 'PX', ttlMs: number, nx: 'NX'): Promise<unknown> | unknown;
    /** Reads a key. */
    get(key: string): Promise<string | null> | string | null;
    /** Deletes a key. */
    del(key: string): Promise<unknown> | unknown;
    /** Optional atomic primitive. Strongly preferred; see the class note. */
    eval?(script: string, numKeys: number, ...args: string[]): Promise<unknown> | unknown;
}
/** Options for the Redis circuit store. */
export interface RedisCircuitStateStoreOptions {
    /** Key prefix. Defaults to `nexus-ai-pro:circuits:`. */
    prefix?: string;
    /** Disables the Lua path even when the client exposes `eval`. */
    useEval?: boolean;
}
/**
 * Shared circuit state in Redis, so every worker behind a load balancer agrees on which providers
 * are down.
 *
 * Probe claims are `SET NX` with an expiry, which is atomic on every Redis. With `eval`, a
 * transition is written only when it is newer than the stored one, in one step; without it, the
 * store compares and writes separately, and a stale transition landing at the wrong moment can
 * briefly win. Workers heal that on their own — a stale "open" is probed and closed after one
 * cooldown — but prefer a client with `eval`.
 */
export declare class RedisCircuitStateStore implements CircuitStateStore {
    private readonly client;
    private readonly prefix;
    private readonly useEval;
    constructor(client: RedisCircuitLikeClient, options?: RedisCircuitStateStoreOptions);
    /** Every provider's shared circuit state. Unreadable entries are skipped. */
    read(): Promise<SharedCircuitState[]>;
    /**
     * Writes a transition, unless a newer one is already stored. Releases the provider's probe claim.
     */
    write(state: SharedCircuitState): Promise<void>;
    /**
     * Claims the right to probe a provider for `ttlMs`. Resolves true for the claimant, including
     * when it already holds the claim.
     */
    claimProbe(providerName: string, owner: string, ttlMs: number): Promise<boolean>;
    private statesKey;
    private probeKey;
}