// Claus Network API status reporter, by MVA (agentminimum.com).
// Runs server-side so browser CORS never matters. No keys, no wallets, no cookies, no logging of visitors.
const BASE = 'https://claus-network-api.vercel.app';
const CHECKS = [
  { name: 'health', path: '/health' },
  { name: 'capabilities', path: '/v1/public/capabilities' }
];
const TIMEOUT_MS = 10000;

async function probe(check) {
  const url = BASE + check.path;
  const started = Date.now();
  const observed_at = new Date(started).toISOString();
  const ctrl = new AbortController();
  const timer = setTimeout(() => ctrl.abort(), TIMEOUT_MS);
  try {
    const res = await fetch(url, { signal: ctrl.signal, headers: { accept: 'application/json' }, cache: 'no-store' });
    const text = await res.text();
    const latency_ms = Date.now() - started;
    let body = null;
    try { body = JSON.parse(text); } catch (e) { body = null; }
    let state = 'OK';
    let reason = null;
    if (!res.ok) { state = 'UNAVAILABLE'; reason = 'HTTP ' + res.status; }
    else if (body === null) { state = 'UNAVAILABLE'; reason = 'response was not JSON'; }
    else if (body && (body.ok === false || ['error', 'down', 'unhealthy'].includes(String(body.status || '').toLowerCase()))) {
      state = 'UNAVAILABLE'; reason = 'endpoint reported itself unhealthy';
    }
    return { name: check.name, url, observed_at, latency_ms, http_status: res.status, state, reason,
      sample: state === 'OK' ? text.slice(0, 600) : text.slice(0, 300) };
  } catch (err) {
    const aborted = err && err.name === 'AbortError';
    return { name: check.name, url, observed_at, latency_ms: Date.now() - started, http_status: null,
      state: 'UNAVAILABLE', reason: aborted ? 'timed out after ' + TIMEOUT_MS + ' ms' : 'request failed: ' + String(err && err.message || err), sample: null };
  } finally { clearTimeout(timer); }
}

module.exports = async (req, res) => {
  const results = await Promise.all(CHECKS.map(probe));
  res.setHeader('Cache-Control', 'no-store, max-age=0');
  res.setHeader('Access-Control-Allow-Origin', '*');
  res.setHeader('Content-Type', 'application/json; charset=utf-8');
  res.status(200).send(JSON.stringify({
    reporter: 'MVA Claus status reporter',
    generated_at: new Date().toISOString(),
    overall: results.every(r => r.state === 'OK') ? 'OK' : 'UNAVAILABLE',
    checks: results
  }, null, 2));
};