import { PassThrough } from "stream";
import { renderToPipeableStream } from "react-dom/server";
import { ServerRouter } from "react-router";
import { createReadableStreamFromReadable, type EntryContext } from "@react-router/node";
import { isbot } from "isbot";
import { addDocumentResponseHeaders } from "./shopify.server";

export const streamTimeout = 5000;

export default async function handleRequest(
  request: Request,
  responseStatusCode: number,
  responseHeaders: Headers,
  reactRouterContext: EntryContext,
) {
  addDocumentResponseHeaders(request, responseHeaders);
  const callbackName = isbot(request.headers.get("user-agent") ?? "") ? "onAllReady" : "onShellReady";
  return new Promise<Response>((resolve, reject) => {
    const { pipe, abort } = renderToPipeableStream(
      <ServerRouter context={reactRouterContext} url={request.url} />,
      {
        [callbackName]: () => {
          const body = new PassThrough();
          const stream = createReadableStreamFromReadable(body);
          responseHeaders.set("Content-Type", "text/html");
          resolve(new Response(stream, { headers: responseHeaders, status: responseStatusCode }));
          pipe(body);
        },
        onShellError: reject,
        onError(error) {
          responseStatusCode = 500;
          console.error(error);
        },
      },
    );
    setTimeout(abort, streamTimeout + 1000);
  });
}