#!/usr/bin/env node
import net from "node:net";
const [proxyHost, proxyPortRaw, targetHost, targetPortRaw] = process.argv.slice(2);
const proxyPort = Number.parseInt(proxyPortRaw || "", 10);
const targetPort = Number.parseInt(targetPortRaw || "", 10);
if (!proxyHost || !Number.isInteger(proxyPort) || !targetHost || !Number.isInteger(targetPort)) {
  console.error("hwlab git-mirror proxy-connect: invalid ProxyCommand arguments");
  process.exit(64);
}
let settled = false;
let tunnelEstablished = false;
function finish(code, message) {
  if (settled) return;
  settled = true;
  if (message) console.error("hwlab git-mirror proxy-connect: " + message);
  process.exit(code);
}
const socket = net.createConnection({ host: proxyHost, port: proxyPort });
let buffer = Buffer.alloc(0);
socket.setTimeout(15000, () => { socket.destroy(); finish(65, "timeout connecting via " + proxyHost + ":" + proxyPort + " to " + targetHost + ":" + targetPort); });
socket.on("connect", () => socket.write("CONNECT " + targetHost + ":" + targetPort + " HTTP/1.1\r\nHost: " + targetHost + ":" + targetPort + "\r\nProxy-Connection: Keep-Alive\r\n\r\n"));
socket.on("error", (error) => finish(tunnelEstablished ? 69 : 66, (tunnelEstablished ? "tunnel socket error: " : "tcp error connecting to proxy: ") + (error && error.message ? error.message : String(error))));
socket.on("close", () => { if (!tunnelEstablished) finish(68, "proxy closed before CONNECT completed via " + proxyHost + ":" + proxyPort + " to " + targetHost + ":" + targetPort); else finish(0); });
function onData(chunk) {
  buffer = Buffer.concat([buffer, chunk]);
  const headerEnd = buffer.indexOf("\r\n\r\n");
  if (headerEnd === -1 && buffer.length < 8192) return;
  if (headerEnd === -1) { socket.destroy(); finish(68, "proxy response header exceeded 8192 bytes before CONNECT status via " + proxyHost + ":" + proxyPort + " to " + targetHost + ":" + targetPort); return; }
  const head = buffer.slice(0, headerEnd + 4).toString("latin1");
  const statusLine = head.split("\r\n", 1)[0] || "";
  const statusCode = Number.parseInt(statusLine.split(" ")[1] || "", 10);
  if (!statusLine.startsWith("HTTP/1.") || !Number.isInteger(statusCode) || statusCode < 200 || statusCode > 299) {
    const safeStatus = statusLine.replace(/[^\x20-\x7e]/g, "?").slice(0, 160);
    socket.destroy();
    finish(67, "proxy CONNECT failed via " + proxyHost + ":" + proxyPort + " to " + targetHost + ":" + targetPort + ": " + safeStatus);
    return;
  }
  socket.off("data", onData);
  socket.setTimeout(0);
  tunnelEstablished = true;
  const rest = buffer.slice(headerEnd + 4);
  if (rest.length) process.stdout.write(rest);
  process.stdin.on("error", () => {});
  process.stdout.on("error", () => {});
  process.stdin.pipe(socket);
  socket.pipe(process.stdout);
}
socket.on("data", onData);