/// <reference types="node" />
/// <reference types="node" />
import http from 'http';
import { Readable, Duplex } from 'stream';
import { HttpProxyAgentOptions } from 'http-proxy-agent';
import { HttpsProxyAgentOptions } from 'https-proxy-agent';
import { SocksProxyAgentOptions } from 'socks-proxy-agent';
import { Agent, AgentConnectOpts } from 'agent-base';
type FindProxyForURL = (req: http.ClientRequest, opts: http.RequestOptions, url: string) => Promise<string | undefined>;
/**
 * The `PacProxyAgent` class.
 *
 * A few different "protocol" modes are supported (supported protocols are
 * backed by the `get-uri` module):
 *
 *   - "pac+data", "data" - refers to an embedded "data:" URI
 *   - "pac+file", "file" - refers to a local file
 *   - "pac+ftp", "ftp" - refers to a file located on an FTP server
 *   - "pac+http", "http" - refers to an HTTP endpoint
 *   - "pac+https", "https" - refers to an HTTPS endpoint
 *
 * @api public
 */
export declare class PacProxyAgent extends Agent {
    resolver: FindProxyForURL;
    opts: PacProxyAgentOptions;
    addCAs: (opts: PacProxyAgentOptions) => Promise<void>;
    casAdded: boolean;
    cache?: Readable;
    constructor(resolver: FindProxyForURL, opts?: PacProxyAgentOptions, addCAs?: (opts: PacProxyAgentOptions) => Promise<void>);
    /**
     * Called when the node-core HTTP client library is creating a new HTTP request.
     *
     * @api protected
     */
    connect(req: http.ClientRequest, opts: AgentConnectOpts): Promise<Duplex | http.Agent>;
}
export declare function getProxyURLFromResolverResult(result: string | undefined): {
    proxy: string;
    url: undefined;
} | {
    proxy: string;
    url: string;
};
type LookupProxyAuthorization = (proxyURL: string, proxyAuthenticate: string | string[] | undefined, state: Record<string, any>) => Promise<string | undefined>;
type HttpsProxyAgentOptions2<Uri> = HttpsProxyAgentOptions<Uri> & {
    lookupProxyAuthorization?: LookupProxyAuthorization;
};
export declare function createPacProxyAgent(resolver: FindProxyForURL, opts?: PacProxyAgentOptions, addCAs?: (opts: PacProxyAgentOptions) => Promise<void>): PacProxyAgent;
type PacProxyAgentOptions = HttpProxyAgentOptions<''> & HttpsProxyAgentOptions2<''> & SocksProxyAgentOptions & {
    fallbackToDirect?: boolean;
    originalAgent?: false | http.Agent;
    _vscodeTestReplaceCaCerts?: boolean;
};
export {};