import { type Schema } from "../schema/Schema.js";
import type { AnyCaller } from "../util/function.js";
import { type RequestMethod, type RequestOptions } from "../util/http.js";
import type { URLString } from "../util/url.js";
import type { EndpointCallback, EndpointHandler } from "./util.js";
/**
 * An abstract API resource definition, used to specify types for e.g. serverless functions.
 *
 * @param method The method of the endpoint, e.g. `GET`
 * @param url Endpoint URL, possibly including placeholders e.g. `https://api.mysite.com/users/{id}`
 * @param payload A `Schema` for the payload of the endpoint.
 * @param result A `Schema` for the result of the endpoint.
 */
export declare class Endpoint<P, R> {
    /** Endpoint method. */
    readonly method: RequestMethod;
    /** Endpoint URL, possibly including placeholders e.g. `https://api.mysite.com/users/{id}` */
    readonly url: URLString;
    /** Payload schema. */
    readonly payload: Schema<P>;
    /** Result schema. */
    readonly result: Schema<R>;
    constructor(method: RequestMethod, url: URLString, payload: Schema<P>, result: Schema<R>);
    /**
     * Return an `EndpointHandler` for this endpoint.
     *
     * @param callback The callback function that implements the logic for this endpoint by receiving the payload and returning the response.
     */
    handler(callback: EndpointCallback<P, R>): EndpointHandler<P, R>;
    /**
     * Handle a request to this endpoint with a callback implementation, with a given payload and request.
     *
     * @param callback The endpoint callback function that implements the logic for this endpoint by receiving the payload and returning the response.
     * @param unsafePayload The payload to pass into the callback (will be validated against this endpoint's payload schema).
     * @param request The entire HTTP request that is being handled (payload was possibly extracted from this somehow).
     *
     * @throws `Feedback` if the payload is invalid.
     * @throws `ValueError` if `callback()` returns an invalid result.
     */
    handle(callback: EndpointCallback<P, R>, unsafePayload: unknown, request: Request, caller?: AnyCaller): Promise<Response>;
    /**
     * Render the URL for this endpoint with the given payload.
     * - URL mioght contain `{placeholder}` values that are replaced with values from the payload.
     */
    renderURL(payload: P, caller?: AnyCaller): string;
    /**
     * Get an HTTP `Request` object for this endpoint.
     * - Validates a payload against this endpoints payload schema
     * - Return an HTTP `Request` that will send it the valid payload to this endpoint.
     *
     * @throws `Feedback` if the payload is invalid.
     */
    request(payload: P, options?: RequestOptions, caller?: AnyCaller): Request;
    /**
     * Validate an HTTP `Response` against this endpoint.
     *
     * @throws `ResponseError` if the response status is not ok (200-299)
     * @throws `ResponseError` if the response content is invalid.
     */
    response(response: Response, caller?: AnyCaller): Promise<R>;
    /**
     * Perform a fetch to this endpoint.
     * - Validate the `payload` against this endpoint's payload schema.
     * - Validate the returned response against this endpoint's result schema.
     *
     * @throws `Feedback` if the payload is invalid.
     * @throws `ResponseError` if the response status is not ok (200-299)
     * @throws `ResponseError` if the response content is invalid.
     */
    fetch(payload: P, options?: RequestOptions, caller?: AnyCaller): Promise<R>;
    /** Convert to string, e.g. `GET https://a.com/user/{id}` */
    toString(): string;
}
/** Extract the payload type from a `Endpoint`. */
export type PayloadType<X extends Endpoint<unknown, unknown>> = X extends Endpoint<infer Y, unknown> ? Y : never;
/** Extract the result type from a `Endpoint`. */
export type EndpointType<X extends Endpoint<unknown, unknown>> = X extends Endpoint<unknown, infer Y> ? Y : never;
/**
 * Represent a GET request to a specified URL, with validated payload and return types.
 * "The GET method requests a representation of the specified resource. Requests using GET should only retrieve data and should not contain a request content."
 */
export declare function GET<P, R>(url: URLString, payload?: Schema<P>, result?: Schema<R>): Endpoint<P, R>;
export declare function GET<P>(url: URLString, payload: Schema<P>): Endpoint<P, undefined>;
export declare function GET<R>(url: URLString, payload: undefined, result: Schema<R>): Endpoint<undefined, R>;
/**
 * Represent a POST request to a specified URL, with validated payload and return types.
 * "The POST method submits an entity to the specified resource, often causing a change in state or side effects on the server.
 */
export declare function POST<P, R>(url: URLString, payload?: Schema<P>, result?: Schema<R>): Endpoint<P, R>;
export declare function POST<P>(url: URLString, payload: Schema<P>): Endpoint<P, undefined>;
export declare function POST<R>(url: URLString, payload: undefined, result: Schema<R>): Endpoint<undefined, R>;
/**
 * Represent a PUT request to a specified URL, with validated payload and return types.
 * "The PUT method replaces all current representations of the target resource with the request content."
 */
export declare function PUT<P, R>(url: URLString, payload?: Schema<P>, result?: Schema<R>): Endpoint<P, R>;
export declare function PUT<P>(url: URLString, payload: Schema<P>): Endpoint<P, undefined>;
export declare function PUT<R>(url: URLString, payload: undefined, result: Schema<R>): Endpoint<undefined, R>;
/**
 * Represent a PATCH request to a specified URL, with validated payload and return types.
 * "The PATCH method applies partial modifications to a resource."
 */
export declare function PATCH<P, R>(url: URLString, payload?: Schema<P>, result?: Schema<R>): Endpoint<P, R>;
export declare function PATCH<P>(url: URLString, payload: Schema<P>): Endpoint<P, undefined>;
export declare function PATCH<R>(url: URLString, payload: undefined, result: Schema<R>): Endpoint<undefined, R>;
/**
 * Represent a DELETE request to a specified URL, with validated payload and return types.
 * "The DELETE method deletes the specified resource."
 */
export declare function DELETE<P, R>(url: URLString, payload?: Schema<P>, result?: Schema<R>): Endpoint<P, R>;
export declare function DELETE<P>(url: URLString, payload: Schema<P>): Endpoint<P, undefined>;
export declare function DELETE<R>(url: URLString, payload: undefined, result: Schema<R>): Endpoint<undefined, R>;