import { build } from "esbuild";
import { readFile, writeFile } from "node:fs/promises";
import { fileURLToPath } from "node:url";

const output = new URL("../public/sw.js", import.meta.url);
const result = await build({
  entryPoints: [fileURLToPath(new URL("../src/lib/pwa/service-worker.ts", import.meta.url))],
  bundle: true,
  format: "iife",
  platform: "browser",
  target: "es2020",
  write: false,
  banner: { js: "// Generated from src/lib/pwa/service-worker.ts; run npm run assets:pwa." },
});
const bytes = result.outputFiles[0].contents;
if (process.argv.includes("--check")) {
  const existing = await readFile(output);
  if (!existing.equals(Buffer.from(bytes))) throw new Error("PWA worker is stale. Run npm run assets:pwa.");
} else {
  const existing = await readFile(output).catch(() => null);
  if (!existing?.equals(Buffer.from(bytes))) await writeFile(output, bytes);
}