/**
 * Copyright (c) OpenLens Authors. All rights reserved.
 * Licensed under MIT License. See LICENSE in root directory for more information.
 */

import { chunk } from "lodash";
import net from "net";
import { parse } from "url";
import type { ClusterProxyApiRequestArgs } from ".";

const skipRawHeaders = new Set(["Host", "Authorization"]);

export interface KubeApiRequestArgs extends ClusterProxyApiRequestArgs {
  restUrl: string;
}

export async function kubeApiRequest({ req, socket, head, cluster, restUrl }: KubeApiRequestArgs) {
  const proxyUrl = `${await cluster.contextHandler.resolveAuthProxyUrl()}/${restUrl}`;
  const apiUrl = parse(cluster.apiUrl);
  const pUrl = parse(proxyUrl);
  const connectOpts = { port: parseInt(pUrl.port), host: pUrl.hostname };
  const proxySocket = new net.Socket();

  proxySocket.connect(connectOpts, () => {
    proxySocket.write(`${req.method} ${pUrl.path} HTTP/1.1\r\n`);
    proxySocket.write(`Host: ${apiUrl.host}\r\n`);

    for (const [key, value] of chunk(req.rawHeaders, 2)) {
      if (skipRawHeaders.has(key)) {
        continue;
      }

      proxySocket.write(`${key}: ${value}\r\n`);
    }

    proxySocket.write("\r\n");
    proxySocket.write(head);
  });

  proxySocket.setKeepAlive(true);
  socket.setKeepAlive(true);
  proxySocket.setTimeout(0);
  socket.setTimeout(0);

  proxySocket.on("data", function (chunk) {
    socket.write(chunk);
  });
  proxySocket.on("end", function () {
    socket.end();
  });
  proxySocket.on("error", function () {
    socket.write(`HTTP/${req.httpVersion} 500 Connection error\r\n\r\n`);
    socket.end();
  });
  socket.on("data", function (chunk) {
    proxySocket.write(chunk);
  });
  socket.on("end", function () {
    proxySocket.end();
  });
  socket.on("error", function () {
    proxySocket.end();
  });
}