const SYDNEY_ORIGIN = "https://sydney.bing.com";
const KEEP_REQ_HEADERS = [
  "accept",
  "accept-encoding",
  "accept-language",
  "connection",
  "cookie",
  "upgrade",
  "user-agent",
  "sec-websocket-extensions",
  "sec-websocket-key",
  "sec-websocket-version",
  "x-request-id",
  "content-length",
  "content-type",
  "access-control-request-headers",
  "access-control-request-method",
];
const IP_RANGE = [
  ["3.2.50.0", "3.5.31.255"], //192,000
  ["3.12.0.0", "3.23.255.255"], //786,432
  ["3.30.0.0", "3.33.34.255"], //205,568
  ["3.40.0.0", "3.63.255.255"], //1,572,864
  ["3.80.0.0", "3.95.255.255"], //1,048,576
  ["3.100.0.0", "3.103.255.255"], //262,144
  ["3.116.0.0", "3.119.255.255"], //262,144
  ["3.128.0.0", "3.247.255.255"], //7,864,320
];

/**
 * 随机整数 [min,max)
 * @param {number} min
 * @param {number} max
 * @returns
 */
const getRandomInt = (min, max) =>
  Math.floor(Math.random() * (max - min)) + min;

/**
 * ip 转 int
 * @param {string} ip
 * @returns
 */
const ipToInt = (ip) => {
  const ipArr = ip.split(".");
  let result = 0;
  result += +ipArr[0] << 24;
  result += +ipArr[1] << 16;
  result += +ipArr[2] << 8;
  result += +ipArr[3];
  return result;
};

/**
 * int 转 ip
 * @param {number} intIP
 * @returns
 */
const intToIp = (intIP) => {
  return `${(intIP >> 24) & 255}.${(intIP >> 16) & 255}.${(intIP >> 8) & 255}.${
    intIP & 255
  }`;
};

const getRandomIP = () => {
  const randIndex = getRandomInt(0, IP_RANGE.length);
  const startIp = IP_RANGE[randIndex][0];
  const endIp = IP_RANGE[randIndex][1];
  const startIPInt = ipToInt(startIp);
  const endIPInt = ipToInt(endIp);
  const randomInt = getRandomInt(startIPInt, endIPInt);
  const randomIP = intToIp(randomInt);
  return randomIP;
};

/**
 * home
 * @param {string} pathname
 * @returns
 */
const home = async (pathname) => {
  const baseUrl =
    "https://raw.githubusercontent.com/adams549659584/go-proxy-bingai/master/";
  let url;
  // if (pathname.startsWith('/github/')) {
  if (pathname.indexOf("/github/") === 0) {
    url = pathname.replace("/github/", baseUrl);
  } else {
    url = baseUrl + "cloudflare/index.html";
  }
  const res = await fetch(url);
  const newRes = new Response(res.body, res);
  if (pathname === "/") {
    newRes.headers.delete("content-security-policy");
    newRes.headers.set("content-type", "text/html; charset=utf-8");
  }
  return newRes;
};

export default {
  /**
   * fetch
   * @param {Request} request
   * @param {*} env
   * @param {*} ctx
   * @returns
   */
  async fetch(request, env, ctx) {
    const currentUrl = new URL(request.url);
    // if (currentUrl.pathname === '/' || currentUrl.pathname.startsWith('/github/')) {
    if (
      currentUrl.pathname === "/" ||
      currentUrl.pathname.indexOf("/github/") === 0
    ) {
      return home(currentUrl.pathname);
    }
    const targetUrl = new URL(
      SYDNEY_ORIGIN + currentUrl.pathname + currentUrl.search
    );

    const newHeaders = new Headers();
    request.headers.forEach((value, key) => {
      // console.log(`old : ${key} : ${value}`);
      if (KEEP_REQ_HEADERS.includes(key)) {
        newHeaders.set(key, value);
      }
    });
    newHeaders.set("host", targetUrl.host);
    newHeaders.set("origin", targetUrl.origin);
    newHeaders.set("referer", "https://www.bing.com/search?q=Bing+AI");
    const randIP = getRandomIP();
    // console.log('randIP : ', randIP);
    newHeaders.set("X-Forwarded-For", randIP);
    const oldUA = request.headers.get("user-agent");
    const isMobile = oldUA.includes("Mobile") || oldUA.includes("Android");
    if (isMobile) {
      newHeaders.set(
        "user-agent",
        "Mozilla/5.0 (iPhone; CPU iPhone OS 15_7 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.7 Mobile/15E148 Safari/605.1.15 BingSapphire/1.0.410427012"
      );
    } else {
      newHeaders.set(
        "user-agent",
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/113.0.0.0 Safari/537.36 Edg/113.0.1774.35"
      );
    }

    // newHeaders.forEach((value, key) => console.log(`${key} : ${value}`));
    const newReq = new Request(targetUrl, {
      method: request.method,
      headers: newHeaders,
      body: request.body,
    });
    // console.log('request url : ', newReq.url);
    const res = await fetch(newReq);
    return res;
  },
};