import type { MethodInfoServerStreaming, MethodInfoUnary, PartialMessage, ServiceType } from "@bufbuild/protobuf";
import { ConnectError } from "./connect-error.js";
import type { Transport } from "./transport.js";
import type { CallOptions } from "./call-options.js";
/**
 * CallbackClient is a simple client that supports unary and server
 * streaming methods. Methods take callback functions, which will be
 * called when a response message arrives, or an error occurs.
 *
 * Client methods return a function that cancels the call. This is a
 * convenient alternative to creating a AbortController and passing
 * its AbortSignal as an option to the method.
 *
 * If a call is cancelled by an AbortController or by the returned
 * cancel-function, ConnectErrors with the code Canceled are
 * silently discarded.
 *
 * CallbackClient is most convenient for use in React effects, where
 * a function returned by the effect is called when the effect is
 * torn down.
 */
export type CallbackClient<T extends ServiceType> = {
    [P in keyof T["methods"]]: T["methods"][P] extends MethodInfoUnary<infer I, infer O> ? (request: PartialMessage<I>, callback: (error: ConnectError | undefined, response: O) => void, options?: CallOptions) => CancelFn : T["methods"][P] extends MethodInfoServerStreaming<infer I, infer O> ? (request: PartialMessage<I>, messageCallback: (response: O) => void, closeCallback: (error: ConnectError | undefined) => void, options?: CallOptions) => CancelFn : never;
};
type CancelFn = () => void;
/**
 * Create a CallbackClient for the given service, invoking RPCs through the
 * given transport.
 */
export declare function createCallbackClient<T extends ServiceType>(service: T, transport: Transport): CallbackClient<T>;
export {};