// Executes web/index.html's script against a stub DOM and fails on anything thrown.
//
// This exists because a ReferenceError at load once blanked the whole UI: a patch
// anchored on a function that no longer existed, so `prefsModal` was referenced but
// never defined. `node --check` passes that happily -- it is a parse, not a run --
// and every server-side test passed too, because the server was fine.
//
//   node tests/page-smoke.js
const fs = require('fs');
const path = require('path');
const vm = require('vm');

const html = fs.readFileSync(path.join(__dirname, '..', 'web', 'index.html'), 'utf8');
const script = html.split('<script>')[1].split('</script>')[0];
const ids = new Set([...html.matchAll(/id="([^"]+)"/g)].map(m => m[1]));

const missing = [];
const el = (name) => new Proxy({ style: {}, dataset: {}, classList: { add(){}, remove(){}, toggle(){}, contains(){ return false; } },
  value: '', textContent: '', innerHTML: '', hidden: false, children: [], firstElementChild: null,
  appendChild(){}, removeChild(){}, remove(){}, insertAdjacentHTML(){}, addEventListener(){},
  setAttribute(){}, getAttribute(){ return null; }, select(){}, setSelectionRange(){}, focus(){},
  replaceWith(){}, querySelector(){ return el('nested'); }, querySelectorAll(){ return []; },
  play(){ return Promise.resolve(); }, pause(){}, closest(){ return null; } },
  { get: (t, k) => k in t ? t[k] : undefined, set: (t, k, v) => (t[k] = v, true) });

const document = {
  querySelector(sel) {
    if (sel.startsWith('#') && !ids.has(sel.slice(1))) { missing.push(sel); return null; }
    return el(sel);
  },
  querySelectorAll: () => [],
  createElement: () => el('created'),
  addEventListener(){}, body: el('body'),
  documentElement: { dataset: {} },
};

const ctx = {
  document, console,
  window: { isSecureContext: false, addEventListener(){} },
  localStorage: { getItem: () => null, setItem(){}, removeItem(){} },
  navigator: { clipboard: undefined, sendBeacon(){}, mediaSession: undefined },
  fetch: (url) => Promise.resolve({
    ok: true, status: 200, text: () => Promise.resolve(''),
    json: () => Promise.resolve(
      String(url).includes('/api/settings')
        ? { schedule: 'every 60m', every_mins: 60, download_dir: '/tmp', max_total_gb: 0, max_age_days: 0 }
        : []),
  }),
  EventSource: function () { this.close = () => {}; },
  MediaMetadata: function () {},
  Blob: function () {},
  setTimeout, clearTimeout, setInterval, clearInterval,
  confirm: () => false, prompt: () => null, alert(){},
  Date, Math, JSON, Object, Array, String, Number, Promise, Error, FormData: function(){},
  URLSearchParams, encodeURIComponent, decodeURIComponent, parseInt, parseFloat, isNaN,
};
ctx.globalThis = ctx;
ctx.window.location = { href: '' };

try {
  vm.createContext(ctx);
  vm.runInContext(script, ctx, { filename: 'index.html<script>', timeout: 5000 });
} catch (e) {
  console.error('FAIL: the page script threw while loading\n  ' + e.stack.split('\n').slice(0, 3).join('\n  '));
  process.exit(1);
}

// The modals are built on demand, so a load-time check never reaches them. Drive the
// ones that construct markup from live data, which is where a bad field reference hides.
const feed = {
  id: 'f', url: 'https://x/rss', title: 'A Feed', image: null, folder: null,
  keywords: ['a'], allow_explicit: false, auto_download: true, max_new_per_check: 3,
  schedule: 'every 6h', schedule_mins: 360, every_mins: 360,
  last_checked: 1, next_check: 2, entries: 1, downloaded: 0, unread: 1, last_error: null,
};
const drive = [
  ['settingsModal', () => ctx.settingsModal(feed)],
  ['settingsModal (no override)', () => ctx.settingsModal({ ...feed, schedule: null, schedule_mins: null })],
  ['downloadLatestModal', () => ctx.downloadLatestModal(feed)],
  ['removeFeed', () => ctx.removeFeed(feed)],
  ['prefsModal', () => ctx.prefsModal()],
  ['logsModal', () => ctx.logsModal()],
  // `const S` is not reachable from here: top-level const/let do not become properties
  // of a vm context the way var and function declarations do.
  ['renderGroup', () => ctx.renderGroup(feed, [{ ...feed, id: 'child', group: 'f', orphaned: true }])],
];
for (const [name, fn] of drive) {
  try {
    const r = fn();
    if (r && typeof r.catch === 'function') r.catch(e => {
      console.error(`FAIL: ${name} rejected: ${e.message}`); process.exit(1);
    });
  } catch (e) {
    console.error(`FAIL: ${name} threw: ${e.message}`);
    process.exit(1);
  }
}

if (missing.length) {
  console.error('FAIL: handlers wired to elements that do not exist: ' + [...new Set(missing)].join(', '));
  process.exit(1);
}
console.log('OK: page script loads clean, every selector it wires at load exists');
// logsModal arms a poll timer; without this the pending interval keeps node alive.
process.exit(0);