const MY_DOMAIN = "www.helloworld.com"const START_PAGE = "https://www.notion.so/hello-world-6f9db3734f914e6b8b247142b3dbac14"
addEventListener('fetch', event => {  event.respondWith(fetchAndApply(event.request))})
const corsHeaders = {  "Access-Control-Allow-Origin": "*",  "Access-Control-Allow-Methods": "GET, HEAD, POST,PUT, OPTIONS",  "Access-Control-Allow-Headers": "Content-Type",}
function handleOptions(request) {  if (request.headers.get("Origin") !== null &&    request.headers.get("Access-Control-Request-Method") !== null &&    request.headers.get("Access-Control-Request-Headers") !== null) {    // Handle CORS pre-flight request.return new Response(null, {      headers: corsHeaders    })  } else {    // Handle standard OPTIONS request.return new Response(null, {      headers: {        "Allow": "GET, HEAD, POST, PUT, OPTIONS",      }    })  }}
async function fetchAndApply(request) {  if (request.method === "OPTIONS") {    return handleOptions(request)  }  let url = new URL(request.url)  let response  if (url.pathname.startsWith("/app") && url.pathname.endsWith("js")) {    response = await fetch(`https://www.notion.so${url.pathname}`)    let body = await response.text()    try {      response = new Response(body.replace(/www.notion.so/g, MY_DOMAIN).replace(/notion.so/g, MY_DOMAIN), response)      // response = new Response(response.body, response)      response.headers.set('Content-Type', "application/x-javascript")      console.log("get rewrite app.js")    } catch (err) {      console.log(err)    }
  } else if ((url.pathname.startsWith("/api"))) {    response = await fetch(`https://www.notion.so${url.pathname}`, {      body: request.body, // must match 'Content-Type' header      headers: {        'content-type': 'application/json;charset=UTF-8',        'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/537.36'      },      method: "POST", // *GET, POST, PUT, DELETE, etc.    })    response = new Response(response.body, response)    response.headers.set('Access-Control-Allow-Origin', "*")  } else if (url.pathname === `/`) {        let pageUrlList = START_PAGE.split("/")    let redrictUrl = `https://${MY_DOMAIN}/${pageUrlList[pageUrlList.length-1]}`return Response.redirect(redrictUrl, 301)  } else {    response = await fetch(`https://www.notion.so${url.pathname}${url.search}`, {      body: request.body, // must match 'Content-Type' header      headers: request.headers,      method: request.method, // *GET, POST, PUT, DELETE, etc.    })  }
  return response}