import type { VextRouteFreshnessIdentity } from "../contract/types.js";
import type { VextHeaders } from "../../types/headers.js";
export interface VextFrontendFreshnessKey {
    route: string;
    path: string;
    query: Record<string, string>;
    locale: string;
    buildId: string;
    partition: string;
    policy: Pick<VextRouteFreshnessIdentity, "mode" | "revalidate" | "clientOnly">;
}
export interface VextFrontendFreshnessResponse {
    payload: unknown;
    status: number;
    headers: VextHeaders;
}
export interface VextFrontendFreshnessEntry {
    schemaVersion: 1;
    key: VextFrontendFreshnessKey;
    keyDigest: string;
    createdAt: string;
    expiresAt: number | null;
    tags: readonly string[];
    response: VextFrontendFreshnessResponse;
}
export interface VextFrontendFreshnessReadResult {
    state: "miss" | "fresh" | "stale";
    entry?: VextFrontendFreshnessEntry;
}
export interface VextFrontendFreshnessWriteInput {
    key: VextFrontendFreshnessKey;
    tags: readonly string[];
    ttlMs?: number;
    response: VextFrontendFreshnessResponse;
}
export interface VextFrontendFreshnessInvalidation {
    route?: string;
    path?: string;
    tag?: string;
    key?: string;
    locale?: string;
    partition?: string;
}
export interface VextFrontendFreshnessInvalidationResult {
    matched: string[];
    removed: string[];
}
/**
 * File-backed public frontend freshness store. Entries are immutable, and the
 * only mutable file is a small metadata pointer written via fsync + rename.
 * A failed write therefore leaves the previous pointer (last-known-good)
 * readable for stale serving and restart recovery.
 */
export declare class VextFrontendFreshnessStore {
    readonly rootDir: string;
    private readonly inFlight;
    constructor(rootDir: string);
    read(key: VextFrontendFreshnessKey): Promise<VextFrontendFreshnessReadResult>;
    write(input: VextFrontendFreshnessWriteInput): Promise<VextFrontendFreshnessEntry>;
    singleFlight<T>(key: VextFrontendFreshnessKey, operation: () => Promise<T>): Promise<{
        value: T;
        leader: boolean;
    }>;
    invalidate(target: VextFrontendFreshnessInvalidation): Promise<VextFrontendFreshnessInvalidationResult>;
    get rootPath(): string;
    private get entriesDir();
    private get pointersDir();
    private readPointer;
    private readEntry;
}
export declare function getFrontendFreshnessStore(rootDir: string): VextFrontendFreshnessStore;
export declare function invalidateFrontendFreshness(rootDir: string, target: VextFrontendFreshnessInvalidation): Promise<VextFrontendFreshnessInvalidationResult>;
export declare function createFreshnessKeyDigest(key: VextFrontendFreshnessKey): string;