import type { Pool, ResolvedModel } from "./router-core.ts";
export interface RateLimitSnapshot {
    remaining?: number;
    limit?: number;
    resetAt?: number;
}
export type PlanStatus = "ok" | "cooldown";
export interface PlanState {
    planKey: string;
    status: PlanStatus;
    cooldownUntil?: number;
    reason?: string;
    lastSnapshot?: RateLimitSnapshot;
    updatedAt: number;
}
export interface QuotaConfig {
    enabled: boolean;
    reserveRatio: number;
    inTurnRetry: boolean;
    maxRetries: number;
    defaultCooldownMs: number;
}
export interface PlanIdentity {
    provider: string;
    baseUrl: string;
    apiKey?: string;
    headers?: Record<string, string>;
    env?: Record<string, string>;
}
export declare const DEFAULT_QUOTA_CONFIG: QuotaConfig;
export declare class QuotaState {
    readonly config: QuotaConfig;
    private readonly plans;
    constructor(config?: QuotaConfig | Partial<QuotaConfig>);
    isAvailable(planKey: string, now: number): boolean;
    recordResponse(planKey: string, status: number, headers: Record<string, string>, provider: string, now: number): PlanState;
    recordRateLimited(planKey: string, retryAfterMs: number | undefined, resetAt: number | undefined, now: number): PlanState;
    snapshot(planKey: string): PlanState | undefined;
    snapshots(): PlanState[];
    /** Returns true when no matching plan is known or at least one matching auth plan is usable. */
    isAnyAvailableMatching(planKeyPrefix: string, now: number): boolean;
    load(file: string): void;
    persist(file: string): void;
    private get;
}
export declare function buildPlanKey(identity: PlanIdentity): string;
export declare function filterPoolByQuota(pool: Pool, quota: QuotaState | undefined, now: number, excluded?: Set<string>, planKeyFor?: (item: ResolvedModel) => string): Pool;
/** Filters models when every persisted auth plan for the same provider endpoint is cooling down. */
export declare function filterPoolByQuotaPlanPrefix(pool: Pool, quota: QuotaState | undefined, now: number): Pool;
export declare function quotaPlanPrefix(provider: string, baseUrl: string): string;
export declare function parseRateLimitHeaders(_provider: string, headers: Record<string, string>, now: number): RateLimitSnapshot;
export declare function parseRfc3339(value: string | undefined): number | undefined;
export declare function parseDuration(value: string | undefined): number | undefined;
export declare function parseRetryAfter(value: string | undefined, now: number): number | undefined;