Pre-rendering or static generation some part of the routes

import { renderToString } from "react-dom/server";
import fs from "node:fs/promises";
import path from "path";
import { createRouter } from "@tanstack/react-router";
import { routeTree } from "../src/routeTree.gen";

async function build() {
  const router = createRouter({ routeTree });
  const mdxRoutes =
    router.routesByPath["/docs/$slug"].options.staticData?.slugs?.map(
      (slug) => `/docs/${slug}`,
    ) ?? [];
  const routes = ["/", ...mdxRoutes];

  for (const route of routes) {
    const html = renderToString(/** what to do */);

    const outputPath = path.join(
      "dist",
      route === "/" ? "index.html" : `${route}/index.html`,
    );

    await fs.mkdir(path.dirname(outputPath), { recursive: true });
    await fs.writeFile(outputPath, html);
  }
}

build().catch(console.error);