import type { Scope } from 'harper';
/** A Connect-style middleware: forwards to `next()` when it does not handle the request. */
export type Middleware = (req: any, res: any, next: (err?: unknown) => void) => void;
/**
 * Compose Connect middlewares into one. Each runs only after the previous calls `next()` without an
 * error; the first to handle the response (by not calling `next`) ends the chain. When all fall through,
 * the composed middleware calls its own `next`. Lets us run, say, an auth check ahead of Vite.
 */
export declare function chain(...middlewares: Middleware[]): Middleware;
/** A request that should receive an HTML document (SPA shell / SSR render) rather than falling through. */
export declare function acceptsHtml(req: any): boolean;
/**
 * Register an HTTP handler with Harper that runs `middleware` first and, for any request the middleware
 * does not handle, falls through to the next Harper layer (e.g. `rest: true` resources) via `nextLayer`.
 */
export declare function registerHttp(scope: Scope, middleware: Middleware, options?: Record<string, unknown>): void;
/** Close the given instance both when the scope closes and when Harper broadcasts a shutdown message. */
export declare function registerShutdown(scope: Scope, close: () => unknown): void;