/** The middleware function signature. */
export type Middleware = (request: Request, context: MiddlewareContext) => Response | void | Promise<Response | void>;
/** Context passed to the middleware function. */
export interface MiddlewareContext {
    /** Helper to continue to the next handler. Can attach headers, params, and locals. */
    next(options?: {
        headers?: Record<string, string>;
        params?: Record<string, string | string[]>;
        locals?: Record<string, unknown>;
    }): void;
    /** Matched route params (only available if the path matches a page route). */
    params?: Record<string, string | string[]>;
    /** Per-request locals (populated by middleware, available to loaders/actions). */
    locals?: Record<string, unknown>;
}
/** Configuration for the middleware module. */
export interface MiddlewareConfig {
    /** Path patterns that trigger the middleware. Supports `:param` and `:param*`. */
    matcher?: string[];
}
export interface LoadedMiddleware {
    handler: Middleware;
    config: MiddlewareConfig;
}
/** Result of running middleware: either a response to short-circuit with, or continue. */
export type MiddlewareResult = {
    kind: "response";
    response: Response;
} | {
    kind: "continue";
    headers?: Record<string, string>;
    params?: Record<string, string | string[]>;
    locals?: Record<string, unknown>;
};
/**
 * Loads the user's `src/middleware.ts` module. Returns `null` if no middleware
 * file exists. Distinguishes "file not found" from "file has errors" (§6):
 * an import error is not silently treated as "no middleware".
 */
export declare function loadMiddleware(root: string): Promise<LoadedMiddleware | null>;
/**
 * Checks if a pathname matches any of the middleware's matcher patterns.
 * If no matcher is configured, the middleware runs for every request.
 *
 * Catch-all patterns (`:param*`) match both the base path and any sub-paths,
 * e.g. `/dashboard/:path*` matches `/dashboard` and `/dashboard/settings/users`.
 */
export declare function matchesMiddleware(pathname: string, config: MiddlewareConfig): boolean;
/**
 * Runs the middleware for a request. Returns the result indicating whether to
 * short-circuit with a response or continue with propagated headers/params/locals.
 *
 * Per §6: cleanup runs in `finally`, response short-circuits the pipeline,
 * headers/params/locals are propagated to downstream handlers.
 */
export declare function runMiddleware(middleware: LoadedMiddleware, request: Request, params?: Record<string, string | string[]>): Promise<MiddlewareResult>;