/**
 * Headless browser verification for PolyCity.
 * Every await is wrapped: the harness can never die silently.
 */
import { chromium } from 'playwright-core';
import { createServer } from 'node:http';
import { readFileSync, existsSync, mkdirSync, readdirSync, writeSync } from 'node:fs';
import { join, extname } from 'node:path';

const LOG = (m) => { try { writeSync(1, m + '\n'); } catch {} };
const DIST = new URL('../dist', import.meta.url).pathname;
const SHOTS = new URL('../shots', import.meta.url).pathname;
if (!existsSync(SHOTS)) mkdirSync(SHOTS);

let last = Date.now();
setInterval(() => {
  if (Date.now() - last > 70000) { LOG('IDLE WATCHDOG — aborting'); process.exit(3); }
}, 5000).unref();
setTimeout(() => { LOG('GLOBAL CAP — aborting'); process.exit(4); }, 360000);
process.on('unhandledRejection', (r) => LOG('UNHANDLED REJECTION: ' + (r?.message || r)));
process.on('uncaughtException', (e) => LOG('UNCAUGHT: ' + (e?.message || e)));

function findChromium() {
  const root = '/root/.cache/ms-playwright';
  const pats = ['chrome-headless-shell-linux64/chrome-headless-shell', 'chrome-linux64/chrome',
    'chrome-linux/headless_shell', 'chrome-linux/chrome'];
  try {
    for (const d of readdirSync(root)) {
      for (const p of pats) { const c = join(root, d, p); if (existsSync(c)) return c; }
    }
  } catch {}
  return null;
}

// static file server
const MIME = { '.html': 'text/html', '.js': 'text/javascript', '.css': 'text/css', '.svg': 'image/svg+xml', '.json': 'application/json', '.webmanifest': 'application/manifest+json' };
const server = createServer((req, res) => {
  let p = req.url.split('?')[0];
  if (p === '/') p = '/index.html';
  try {
    res.writeHead(200, { 'content-type': MIME[extname(p)] || 'application/octet-stream' });
    res.end(readFileSync(join(DIST, p)));
  } catch { res.writeHead(404); res.end(); }
});
await new Promise(r => server.listen(4173, r));
LOG('static server on :4173');

const errors = [];
let closing = false;

const exe = findChromium();
LOG('browser: ' + exe);
const browser = await chromium.launch({ executablePath: exe, args: ['--no-sandbox', '--enable-unsafe-swiftshader'] });
browser.on('disconnected', () => { if (!closing) errors.push('BROWSER DISCONNECTED'); });

const page = await browser.newPage({ viewport: { width: 800, height: 520 }, deviceScaleFactor: 1 });
page.setDefaultTimeout(9000);
page.on('pageerror', e => errors.push('PAGEERROR: ' + e.message));
page.on('console', m => { if (m.type() === 'error') errors.push('CONSOLE: ' + m.text()); });
page.on('crash', () => errors.push('PAGE CRASHED'));

/** race-guarded runner: never hangs, never dies silently */
async function safe(label, fn, ms = 15000) {
  last = Date.now();
  let timer;
  const timeout = new Promise((_, rej) => { timer = setTimeout(() => rej(new Error('TIMEOUT ' + label)), ms); });
  try {
    const v = await Promise.race([Promise.resolve().then(fn), timeout]);
    clearTimeout(timer);
    return v;
  } catch (e) {
    clearTimeout(timer);
    LOG('  [safe] ' + label + ' → ' + String(e.message || e).split('\n')[0]);
    return null;
  }
}
const sleep = (ms) => safe(`sleep ${ms}`, () => new Promise(r => setTimeout(r, ms)), ms + 3000);

await safe('goto', () => page.addInitScript(() => {
  localStorage.setItem('polycity.settings.v1', JSON.stringify({ sound: false, shadows: false, autosave: true, minimap: true }));
}));
await safe('load', () => page.goto('http://127.0.0.1:4173/', { waitUntil: 'load', timeout: 20000 }));
LOG('page loaded');
await sleep(3200);

await safe('shot-boot', () => page.screenshot({ path: join(SHOTS, '01-boot.png'), timeout: 12000 }));
await safe('help-close', async () => {
  const b = await page.$('#helpClose');
  if (b) await b.click();
});

// ---- build the town through the real game API (deterministic) ----
const built = await safe('build-town', () => page.evaluate(() => {
  const g = window.POLYCITY, city = g.city, grid = city.grid;
  const free4 = (x, z) => {
    for (let dz = 0; dz < 2; dz++) for (let dx = 0; dx < 2; dx++) {
      if (!grid.inB(x + dx, z + dz)) return false;
      const i = grid.idx(x + dx, z + dz);
      if (grid.terrain[i] !== 0 || grid.struct[i] || grid.zone[i]) return false;
    }
    return true;
  };
  const spot = (cx, cz) => {
    for (let r = 0; r < 40; r++) for (let z = cz - r; z <= cz + r; z++) for (let x = cx - r; x <= cx + r; x++) {
      if (free4(x, z)) return [x, z];
    }
    return null;
  };
  // road cross
  for (let x = 18; x < 46; x++) city.placeStruct(1, x, 32);
  for (let z = 20; z < 44; z++) city.placeStruct(1, 32, z);
  // districts
  const rect = (x0, z0, x1, z1, zid) => {
    const t = [];
    for (let z = z0; z <= z1; z++) for (let x = x0; x <= x1; x++) t.push([x, z]);
    city.placeZone(zid, t);
  };
  rect(19, 28, 30, 31, 1);   // residential north-west
  rect(34, 28, 45, 31, 2);   // commercial north-east
  rect(34, 34, 45, 38, 3);   // industrial south-east
  rect(19, 34, 26, 37, 2);   // small commercial SW
  // coal plant + services
  const plant = spot(22, 41); if (plant) city.placeStruct(2, plant[0], plant[1]);
  const put = (sid, cx, cz) => { const p = spot(cx, cz); if (p) city.placeStruct(sid, p[0], p[1]); };
  put(5, 21, 33);  // police
  put(6, 24, 33);  // fire
  put(7, 27, 33);  // hospital
  put(8, 36, 33);  // school
  put(9, 29, 30);  // park
  put(10, 35, 32); // plaza
  return {
    roads: [...grid.struct].filter(v => v === 1).length,
    powerCap: city.stats.powerCap,
    money: Math.round(city.money)
  };
}, 25000));
LOG('built town: ' + JSON.stringify(built));

await safe('shot-built', () => page.screenshot({ path: join(SHOTS, '02-built.png'), timeout: 12000 }));

// ---- simulate ~14 months at fast speed ----
await safe('speed2', () => page.click('#speedControls [data-speed="2"]'));
for (let k = 0; k < 7; k++) {
  await sleep(2000);
  const s = await safe('probe' + k, () => page.evaluate(() => ({
    pop: window.POLYCITY.city.stats.pop,
    dev: [...window.POLYCITY.city.grid.level].filter(v => v > 0).length
  })), 8000);
  LOG(`t+${(k + 1) * 2}s pop=${s?.pop ?? '?'} dev=${s?.dev ?? '?'}`);
}

const state = await safe('state', () => page.evaluate(() => {
  const g = window.POLYCITY, c = g.city;
  return {
    money: c.money, pop: c.stats.pop, jobs: c.stats.jobs,
    happy: c.stats.happiness, powerCap: c.stats.powerCap, powerUse: c.stats.powerUse,
    brownouts: c.stats.brownouts, monthIndex: c.monthIndex,
    developed: [...c.grid.level].filter(v => v > 0).length,
    levels123: [1, 2, 3].map(L => [...c.grid.level].filter(v => v === L).length),
    cars: g._parts.renderer.traffic.agents.length
  };
}), 10000);
LOG('STATE: ' + JSON.stringify(state));

await safe('shot-grown', () => page.screenshot({ path: join(SHOTS, '03-grown.png'), timeout: 12000 }));

// query popup via API
await safe('query', () => page.evaluate(() => window.POLYCITY.queryTile({ x: 25, z: 30 }, 60, 60)));

// panels
for (const [btn, name] of [['#btnBudget', 'budget'], ['#btnStats', 'stats'], ['#btnMenu', 'menu']]) {
  await safe('panel-' + name, async () => {
    await page.click(btn);
    await sleep(350);
    await page.screenshot({ path: join(SHOTS, `08-${name}.png`), timeout: 12000 });
    if (name !== 'menu') await page.keyboard.press('Escape');
  });
}
await safe('final-shot', () => page.screenshot({ path: join(SHOTS, '09-final.png'), timeout: 12000 }));

closing = true;
await safe('close-browser', () => browser.close());
server.close();

let fail = Boolean(!state || !built);
if (!built?.roads || built.roads < 50) { LOG('FAIL: roads missing'); fail = true; }
if (!state) fail = true;
else {
  if (!(state.pop > 50)) { LOG('FAIL: population did not grow: ' + state.pop); fail = true; }
  if (!(state.developed > 10)) { LOG('FAIL: too few developments: ' + state.developed); fail = true; }
  if (!(state.powerCap > 0 && state.powerUse > 0)) { LOG('FAIL: power not flowing'); fail = true; }
  if (!(state.cars > 0)) { LOG('FAIL: traffic dead'); fail = true; }
}
for (const e of errors) { LOG('ERR: ' + e); if (!e.includes('favicon')) fail = true; }
LOG(fail ? 'SMOKE TEST FAILED' : 'SMOKE TEST PASSED');
process.exit(fail ? 1 : 0);