/**
 * When running in Node.js, this function configures the global fetch
 * implementation to use a proxy if one is set in the environment.
 *
 * It must be called before any SDK methods are called.
 *
 * This is useful when running a tool like mitmproxy to inspect HTTP traffic
 * during development.
 */
export async function configureProxy() {
  // Bun's fetch client automatically recognises environment variables for
  // proxy configuration.
  if ("Bun" in globalThis) {
    return;
  }

  const proxyKey = [
    "HTTPS_PROXY",
    "https_proxy",
    "HTTP_PROXY",
    "http_proxy",
  ].find((k) => process.env[k]);
  if (!proxyKey) {
    return;
  }

  const proxy = process.env[proxyKey];
  if (!proxy) {
    return;
  }
  console.log("Using proxy:", proxy);

  const undici = await import("undici");
  const proxyAgent = new undici.ProxyAgent(proxy);
  undici.setGlobalDispatcher(proxyAgent);
}