// E2E part 4: TTL indexes through the official Node driver.
// createIndex({expireAfterSeconds}), the option round-tripping through
// listIndexes, background expiry of past-dated documents, and the specs the
// server must reject with CannotCreateIndex (67).
//
// The server must run with a short sweep interval, e.g.
//   zig-out/bin/multiforadb --port 27020 --db /tmp/mfdb-e2e.log --ttl-sweep-secs 1
const { MongoClient } = require('mongodb');

const URL = 'mongodb://127.0.0.1:27020';
const results = [];
function check(name, cond, detail = '') {
  results.push({ name, ok: !!cond, detail: String(detail) });
  if (!cond) console.error(`  ✗ ${name} ${detail}`);
}

const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

/// Poll until `fn()` is true or the deadline passes; expiry is a background
/// sweep, so the exact moment a document disappears is not fixed.
async function waitFor(fn, timeoutMs = 15000, stepMs = 250) {
  const deadline = Date.now() + timeoutMs;
  while (Date.now() < deadline) {
    if (await fn()) return true;
    await sleep(stepMs);
  }
  return false;
}

async function expectCode(fn, code, name) {
  let err = null;
  try {
    await fn();
  } catch (e) {
    err = e;
  }
  check(name, err && err.code === code, err ? `code ${err.code}: ${err.message}` : 'no error');
}

async function main() {
  const client = new MongoClient(URL, { serverSelectionTimeoutMS: 5000 });
  await client.connect();
  const db = client.db('e2e4');
  const coll = db.collection('sessions');
  await coll.drop().catch(() => {});

  // --- createIndex + listIndexes round-trip ---
  await coll.createIndex({ expireAt: 1 }, { expireAfterSeconds: 1 });
  const idxs = await coll.indexes();
  const ttlIdx = idxs.find((i) => i.name === 'expireAt_1');
  check('TTL index listed', !!ttlIdx, JSON.stringify(idxs));
  check('expireAfterSeconds reported', ttlIdx && Number(ttlIdx.expireAfterSeconds) === 1, JSON.stringify(ttlIdx));
  check('_id_ has no expireAfterSeconds', idxs.find((i) => i.name === '_id_').expireAfterSeconds === undefined);

  // Idempotent re-create of the same spec.
  await coll.createIndex({ expireAt: 1 }, { expireAfterSeconds: 1 });
  check('idempotent re-create', (await coll.indexes()).filter((i) => i.name === 'expireAt_1').length === 1);

  // --- expiry ---
  const now = Date.now();
  await coll.insertMany([
    { _id: 'past', expireAt: new Date(now - 60_000) },
    { _id: 'future', expireAt: new Date(now + 3_600_000) },
    { _id: 'string', expireAt: 'tomorrow' },
    { _id: 'missing' },
    // An array of dates expires on its earliest member.
    { _id: 'array', expireAt: [new Date(now - 60_000), new Date(now + 3_600_000)] },
  ]);
  check('all five inserted', (await coll.countDocuments({})) === 5);

  const gone = await waitFor(async () => (await coll.countDocuments({ _id: 'past' })) === 0);
  check('past-dated doc expired', gone);
  check('array doc expired on earliest date', (await coll.countDocuments({ _id: 'array' })) === 0);
  const survivors = (await coll.find({}).toArray()).map((d) => d._id).sort();
  check('future/string/missing survive', JSON.stringify(survivors) === '["future","missing","string"]', JSON.stringify(survivors));

  // Expiry is a real delete: it holds after the sweeper has run again.
  await sleep(1500);
  check('expired docs stay deleted', (await coll.countDocuments({})) === 3);

  // --- rejected specs ---
  const bad = db.collection('bad');
  await expectCode(
    () => bad.createIndex({ a: 1, b: 1 }, { expireAfterSeconds: 60 }),
    67,
    'compound TTL rejected with 67',
  );
  await expectCode(
    () => bad.createIndex({ a: 1 }, { expireAfterSeconds: -1 }),
    67,
    'negative expireAfterSeconds rejected with 67',
  );
  await expectCode(
    () => bad.createIndex({ a: 1 }, { expireAfterSeconds: 'soon' }),
    67,
    'non-numeric expireAfterSeconds rejected with 67',
  );
  await expectCode(
    () => bad.createIndex({ a: 1 }, { expireAfterSeconds: 2147483648 }),
    67,
    'expireAfterSeconds past 2147483647 rejected with 67',
  );
  await expectCode(
    () => bad.createIndex({ _id: 1 }, { expireAfterSeconds: 60 }),
    197,
    'TTL on _id rejected with 197',
  );
  // Same name and key with a different expiry: IndexOptionsConflict (85),
  // exactly as MongoDB does (the change belongs to collMod).
  await expectCode(
    () => coll.createIndex({ expireAt: 1 }, { expireAfterSeconds: 90 }),
    85,
    'changed expiry gives IndexOptionsConflict',
  );

  // expireAfterSeconds 0 is legal: expire at exactly the stored instant.
  const zero = db.collection('zero');
  await zero.drop().catch(() => {});
  await zero.createIndex({ at: 1 }, { expireAfterSeconds: 0 });
  await zero.insertOne({ _id: 'now', at: new Date(Date.now() - 1000) });
  check('expireAfterSeconds 0 accepted', (await zero.indexes()).some((i) => Number(i.expireAfterSeconds) === 0));
  check('expireAfterSeconds 0 expires', await waitFor(async () => (await zero.countDocuments({})) === 0));

  await client.close();

  const failed = results.filter((r) => !r.ok);
  console.log(`\n${results.length - failed.length}/${results.length} checks passed`);
  if (failed.length) {
    console.log('FAILED:', failed.map((f) => f.name).join(', '));
    process.exit(1);
  }
  console.log('E2E4_OK');
}

main().catch((e) => {
  console.error('E2E4_FAIL', e);
  process.exit(1);
});