import { WorkerEntrypoint } from "cloudflare:workers";
import { captureContext } from "./capture.js";
import { CAPTURE_HEADER, DEMO_EMAIL, DEMO_HOST } from "./config.js";

export class GatewayMiddleware extends WorkerEntrypoint {
  async handle(request, context, next) {
    const headers = new Headers(request.headers);
    headers.delete(CAPTURE_HEADER);
    const url = new URL(request.url);

    if (url.hostname === DEMO_HOST && request.method === "GET" &&
        (url.pathname === "/" || url.pathname === "/context")) {
      // Gateway supplies the context, including lazy identity and posture.
      const snapshot = await captureContext(request, context);

      if (snapshot.identity.value?.email === DEMO_EMAIL) {
        // Save privately before continuing the original request to the site.
        const ticket = await this.env.CONTEXT_VIEWER.capture(snapshot);
        headers.set(CAPTURE_HEADER, ticket);
      }
    }

    // Continue to the original destination using Gateway routing and egress.
    return next(new Request(request, { headers }));
  }
}

export default {
  fetch() {
    return new Response("Gateway RPC entrypoint only.", { status: 403 });
  },
};