import { readFile, readdir } from "node:fs/promises";
import path from "node:path";
import { fileURLToPath } from "node:url";

const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..");
const packageJson = JSON.parse(
  await readFile(path.join(root, "package.json"), "utf8"),
);
const engineDirectory = path.join(root, "public", "engines");
const entries = (await readdir(engineDirectory)).sort();

if (
  packageJson.version !== "0.1.0" ||
  entries.length !== 1 ||
  entries[0] !== "README.md"
) {
  throw new Error(
    "The ECMAScript release must contain only the documented native-browser engine placeholder.",
  );
}

console.log(
  "Regex Tools 0.1.0 uses the native browser RegExp engine; no external engine pack needs building.",
);