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

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const ROOT = path.resolve(__dirname, "..");
const PRESENCES_DIR = path.join(ROOT, "presences");

async function listPresences() {
  const entries = await readdir(PRESENCES_DIR, { withFileTypes: true });
  return entries.filter((e) => e.isDirectory()).map((e) => e.name);
}

async function readMetadata(presenceDir) {
  return JSON.parse(await readFile(path.join(presenceDir, "metadata.json"), "utf8"));
}

async function ensureDistExists(presenceDir, slug) {
  const distFile = path.join(presenceDir, "dist", "presence.js");
  try {
    await stat(distFile);
  } catch {
    throw new Error(`dist/presence.js missing for ${slug} — run "npm run build" first`);
  }
}

async function main() {
  const slugs = await listPresences();
  const entries = [];
  for (const slug of slugs) {
    const dir = path.join(PRESENCES_DIR, slug);
    const meta = await readMetadata(dir);
    await ensureDistExists(dir, slug);
    entries.push({
      id: meta.id,
      name: meta.name,
      description: meta.description,
      version: meta.version,
      author: meta.author,
      match: meta.match,
      ...(meta.icon ? { icon: meta.icon } : {}),
      ...(typeof meta.tickInterval === "number" ? { tickInterval: meta.tickInterval } : {}),
    });
  }
  entries.sort((a, b) => a.id.localeCompare(b.id));
  const index = {
    generatedAt: new Date().toISOString(),
    presences: entries,
  };
  await writeFile(path.join(ROOT, "index.json"), JSON.stringify(index, null, 2) + "\n");
  console.log(`Wrote index.json (${entries.length} presence${entries.length === 1 ? "" : "s"})`);
}

await main();