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import type { MiddlewareHandler } from "astro"; // PostHog reverse proxy — the browser SDK targets a first-party path and we// forward to PostHog's ingest + asset hosts. Keeps events flowing past// adblockers that match *.posthog.com. See// https://posthog.com/docs/advanced/proxy/cloudflare//// The path MUST sit under a prefix that the cloud worker's edge forwards to// this worker. On the production apex (executor.sh) the cloud worker owns the// custom domain and only proxies an allow-list to executor-marketing; `/api/*`// stays in cloud (it has its own posthog proxy on a randomized path), so a// top-level `/api/...` path here 404s. `/_astro` IS forwarded, so we ride it.const POSTHOG_INGEST_HOST = "us.i.posthog.com";const POSTHOG_ASSETS_HOST = "us-assets.i.posthog.com";const POSTHOG_PROXY_PATH = "/_astro/_ph"; export const onRequest: MiddlewareHandler = async (context, next) => {  const { pathname } = new URL(context.request.url);  if (pathname !== POSTHOG_PROXY_PATH && !pathname.startsWith(`${POSTHOG_PROXY_PATH}/`)) {    return next();  }   const url = new URL(context.request.url);  url.hostname = pathname.startsWith(`${POSTHOG_PROXY_PATH}/static/`)    ? POSTHOG_ASSETS_HOST    : POSTHOG_INGEST_HOST;  url.protocol = "https:";  url.port = "";  url.pathname = pathname.slice(POSTHOG_PROXY_PATH.length) || "/";   const upstream = new Request(url, context.request);  upstream.headers.delete("cookie");  return fetch(upstream);};