/**
 * Auth Middleware Registry for B2C SDK.
 *
 * Provides a middleware system specifically for authentication requests (OAuth token requests).
 * This is separate from the HTTP middleware registry because auth requests bypass the
 * standard openapi-fetch client middleware chain.
 *
 * ## SDK Usage
 *
 * ```typescript
 * import { globalAuthMiddlewareRegistry, AuthMiddlewareProvider } from '@salesforce/b2c-tooling-sdk/auth';
 *
 * const loggingProvider: AuthMiddlewareProvider = {
 *   name: 'auth-logger',
 *   getMiddleware() {
 *     return {
 *       onRequest({ request }) {
 *         console.log(`[Auth] ${request.method} ${request.url}`);
 *         return request;
 *       },
 *       onResponse({ response }) {
 *         console.log(`[Auth] ${response.status}`);
 *         return response;
 *       },
 *     };
 *   },
 * };
 *
 * globalAuthMiddlewareRegistry.register(loggingProvider);
 * ```
 *
 * ## CLI Plugin Usage
 *
 * Plugins can provide auth middleware via the `b2c:auth-middleware` hook.
 *
 * @module auth/middleware
 */
/**
 * Middleware interface for authentication requests.
 *
 * Similar to openapi-fetch's Middleware interface, but simplified for auth requests.
 */
export interface AuthMiddleware {
    /**
     * Called before the auth request is sent.
     * Can modify the request or return a new one.
     *
     * @param params - Object containing the request
     * @returns Modified request, or void to use original
     */
    onRequest?(params: {
        request: Request;
    }): Promise<Request | void>;
    /**
     * Called after the auth response is received.
     * Can modify the response or return a new one.
     *
     * @param params - Object containing request and response
     * @returns Modified response, or void to use original
     */
    onResponse?(params: {
        request: Request;
        response: Response;
    }): Promise<Response | void>;
}
/**
 * Middleware provider that supplies middleware for auth requests.
 *
 * @example
 * ```typescript
 * const provider: AuthMiddlewareProvider = {
 *   name: 'user-agent',
 *   getMiddleware() {
 *     return {
 *       onRequest({ request }) {
 *         request.headers.set('User-Agent', 'my-app/1.0');
 *         return request;
 *       },
 *     };
 *   },
 * };
 * ```
 */
export interface AuthMiddlewareProvider {
    /**
     * Human-readable name for the provider (used in logging/debugging).
     */
    readonly name: string;
    /**
     * Returns middleware for auth requests.
     *
     * @returns Middleware to apply, or undefined to skip
     */
    getMiddleware(): AuthMiddleware | undefined;
}
/**
 * Registry for auth middleware providers.
 *
 * The registry collects middleware from multiple providers and returns
 * them in registration order when requested during OAuth token requests.
 *
 * ## Usage Modes
 *
 * **SDK Mode**: Register providers directly via `register()`:
 * ```typescript
 * globalAuthMiddlewareRegistry.register(myProvider);
 * ```
 *
 * **CLI Mode**: Providers are collected via the `b2c:auth-middleware` hook
 * and registered during command initialization.
 */
export declare class AuthMiddlewareRegistry {
    private providers;
    /**
     * Registers a middleware provider.
     *
     * Providers are called in registration order when middleware is requested.
     *
     * @param provider - The provider to register
     */
    register(provider: AuthMiddlewareProvider): void;
    /**
     * Unregisters a middleware provider by name.
     *
     * @param name - The name of the provider to remove
     * @returns true if a provider was removed, false if not found
     */
    unregister(name: string): boolean;
    /**
     * Collects middleware from all providers.
     *
     * @returns Array of middleware in registration order
     */
    getMiddleware(): AuthMiddleware[];
    /**
     * Clears all registered providers.
     *
     * Primarily useful for testing.
     */
    clear(): void;
    /**
     * Returns the number of registered providers.
     */
    get size(): number;
    /**
     * Returns the names of all registered providers.
     */
    getProviderNames(): string[];
}
/**
 * Global auth middleware registry instance.
 *
 * This is the default registry used by OAuth strategies. Register
 * middleware providers here to have them applied to token requests.
 *
 * @example
 * ```typescript
 * import { globalAuthMiddlewareRegistry } from '@salesforce/b2c-tooling-sdk/auth';
 *
 * globalAuthMiddlewareRegistry.register({
 *   name: 'user-agent',
 *   getMiddleware() {
 *     return {
 *       onRequest({ request }) {
 *         request.headers.set('User-Agent', 'my-app/1.0');
 *         return request;
 *       },
 *     };
 *   },
 * });
 * ```
 */
export declare const globalAuthMiddlewareRegistry: AuthMiddlewareRegistry;
/**
 * Applies auth middleware to a request.
 *
 * This helper applies all registered `onRequest` middleware in order,
 * accumulating modifications to the request.
 *
 * @param request - The original request
 * @param middleware - Array of middleware to apply
 * @returns The modified request
 */
export declare function applyAuthRequestMiddleware(request: Request, middleware: AuthMiddleware[]): Promise<Request>;
/**
 * Applies auth middleware to a response.
 *
 * This helper applies all registered `onResponse` middleware in order,
 * accumulating modifications to the response.
 *
 * @param request - The original request (for context)
 * @param response - The response to process
 * @param middleware - Array of middleware to apply
 * @returns The modified response
 */
export declare function applyAuthResponseMiddleware(request: Request, response: Response, middleware: AuthMiddleware[]): Promise<Response>;