/**
 * Enhanced proxy-aware fetch implementation for AI SDK providers
 * Supports HTTP/HTTPS, SOCKS4/5, authentication, and NO_PROXY bypass
 * Lightweight implementation extracted from research of major proxy packages
 */
import type { ProxyAgent } from "undici";
import type { GoogleGenAIHttpOptions } from "../types/index.js";
/**
 * Classify a fetch failure as a transient network error worth retrying.
 *
 * undici's `fetch()` wraps the real failure in `TypeError: fetch failed`
 * with the actionable code (`ECONNRESET`, `UND_ERR_SOCKET`, ...) on
 * `error.cause` — sometimes nested another level (e.g. SocketError inside
 * a ConnectTimeoutError). Walk the cause chain so those are recognized;
 * checking only the top-level error silently classified every undici
 * connection death as non-retryable.
 *
 * Deliberately NOT retried: `UND_ERR_HEADERS_TIMEOUT` / `UND_ERR_BODY_TIMEOUT`
 * — those already waited out undici's own long deadline (default 300s), and
 * replaying them can triple a stall under the caller's wall-clock budget.
 *
 * Exported for direct coverage by the no-API test suite.
 */
export declare function isTransientNetworkError(error: unknown): boolean;
/**
 * The dispatcher a request to `targetUrl` must use to go through the proxy the
 * environment configures, or `null` when none applies (no proxy variable for
 * the URL's scheme, or the host is listed in NO_PROXY).
 *
 * Unlike the fetch from {@link createProxyFetch}, a caller that needs a
 * request to be proxied or refused (a download whose destination was vetted
 * under proxy rules) gets no fallback to a direct connection from this: a proxy
 * that cannot be used (an unsupported SOCKS URL, an unparsable URL) throws.
 */
export declare function getProxyDispatcherForUrl(targetUrl: string): Promise<ProxyAgent | null>;
/**
 * Create a proxy-aware fetch function with enhanced capabilities
 * Supports HTTP/HTTPS, SOCKS4/5, authentication, and NO_PROXY bypass
 */
export declare function createProxyFetch(): typeof fetch;
/**
 * Mask credentials in a proxy URL for safe logging/reporting.
 *
 * Exported so provider-side fetch loggers (lmStudio, llamaCpp, deepseek,
 * nvidiaNim) can sanitize upstream URLs before emitting warnings — reverse-
 * proxied deployments can embed credentials or signed query params in the
 * base URL, and those should never reach application logs verbatim.
 */
export declare function maskProxyUrl(url: string | null | undefined): string | null;
/**
 * Get enhanced proxy status information
 */
export declare function getProxyStatus(): {
    enabled: boolean;
    httpProxy: string | null;
    httpsProxy: string | null;
    allProxy: string | null;
    socksProxy: string | null;
    noProxy: string | null;
    method: string;
    capabilities: string[];
};
/**
 * `httpOptions` fragment that routes the @google/genai SDK through the
 * configured proxy, or nothing when none is configured.
 *
 * The SDK calls global `fetch` unless `HttpOptions.fetch` is set (declared and
 * used from 2.23.0), and global `fetch` does not read HTTP_PROXY / HTTPS_PROXY
 * unless Node itself was started with env-proxy support. The proxy-aware fetch
 * is passed only when a proxy is configured: with none, the SDK keeps its own
 * request path instead of gaining this module's trace headers and retries.
 *
 * Covers the SDK's `generateContent`, `generateContentStream` and
 * `embedContent` requests. It does not reach Gemini Live websockets or the
 * Application Default Credentials token requests.
 */
export declare function googleSdkProxyHttpOptions(): GoogleGenAIHttpOptions;