#!/usr/bin/env node
/**
 * verae-fleet — catalog, monitor, restart, pause.
 *
 * Local (no daemon): list
 * Daemon:            serve | monitor
 * Against daemon:    status | start | stop | pause | resume | restart
 */
import http from 'node:http';
import { loadFleet, listServices } from './load.js';
import { Supervisor } from './supervisor.js';
import { Monitor } from './monitor.js';
import { startControlServer } from './server.js';

const loaded = loadFleet();
const [cmd = 'help', target] = process.argv.slice(2);
const BASE = process.env.FLEET_URL || `http://127.0.0.1:${loaded.control.port}`;

function print(obj) {
  process.stdout.write(`${typeof obj === 'string' ? obj : JSON.stringify(obj, null, 2)}\n`);
}

function help() {
  print(`verae-fleet

  list                         services, config files, replica min/max
  serve                        start floors + monitor + UI ${BASE}/
  monitor                      same without printing extra
  status                       GET daemon status
  start  <service>             turn on, spawn up to min
  stop   <service|instance>    turn off (service disable) or stop one replica
  pause  <service|instance>    pause (does not count toward tree-node floor)
  resume <service|instance>
  restart <instance>           kill + respawn
  reconcile                    force floor check

Central spec:  fleet.json
Machines:      machines.json  (add hosts to spread replicas)
Per service:   services/<id>.json
Remote SSH:    machines.json user + host + identityFile (path only)
  ssh-check [id]               test SSH login (default ns1)
`);
}

function api(method, pathname) {
  return new Promise((resolve, reject) => {
    const u = new URL(pathname, BASE);
    const req = http.request(
      { hostname: u.hostname, port: u.port, path: u.pathname, method, timeout: 8000 },
      (res) => {
        const chunks = [];
        res.on('data', (c) => chunks.push(c));
        res.on('end', () => {
          const raw = Buffer.concat(chunks).toString('utf8');
          try {
            resolve({ status: res.statusCode, body: JSON.parse(raw) });
          } catch {
            resolve({ status: res.statusCode, body: raw });
          }
        });
      },
    );
    req.on('error', reject);
    req.end();
  });
}

async function main() {
  if (cmd === 'help' || cmd === '-h' || cmd === '--help') return help();
  if (cmd === 'list') {
    for (const r of listServices(loaded)) {
      print(
        `${r.id.padEnd(22)} min=${String(r.min).padStart(2)} max=${String(r.max).padStart(2)} floor=${r.keepFloor ? 'yes' : 'no '} managed=${r.managed ? 'yes' : 'no '} ${r.configPath}`,
      );
    }
    print(`\ncentral replica spec: ${loaded.fleetPath}`);
    print(`tree-node floor:      min=${loaded.services['tree-node'].min} keepFloor=${loaded.services['tree-node'].keepFloor}`);
    print('\nmachines:');
    for (const m of loaded.machines) {
      const ssh = m.kind === 'ssh' ? `${m.user}@${m.host} key=${m.identityFile}` : m.host;
      print(`  ${m.id.padEnd(12)} ${m.kind.padEnd(6)} ${m.enabled ? 'on ' : 'off'} cap=${m.capacity} ${ssh}`);
    }
    return;
  }
  if (cmd === 'ssh-check') {
    const { sshCheck } = await import('./ssh.js');
    const id = target || 'ns1';
    const m = loaded.machines.find((x) => x.id === id);
    if (!m) throw new Error(`unknown machine ${id}`);
    print(await sshCheck(m));
    return;
  }
  if (cmd === 'serve' || cmd === 'monitor') {
    const sup = new Supervisor({ loaded });
    for (const id of Object.keys(loaded.services)) {
      const s = loaded.services[id];
      if (s.managed && s.enabled && s.min > 0) await sup.startService(id);
    }
    const mon = new Monitor(sup);
    await mon.tick();
    mon.start();
    startControlServer(sup, mon);
    print(`fleet ${cmd} pid=${process.pid}\nUI ${BASE}/\nSIGINT stops all managed replicas`);
    process.on('SIGINT', async () => {
      mon.stop();
      await sup.stopAll();
      process.exit(0);
    });
    process.on('SIGTERM', async () => {
      mon.stop();
      await sup.stopAll();
      process.exit(0);
    });
    return;
  }

  const instance = target && /-\d+$/.test(target);
  const map = {
    status: ['GET', '/api/status'],
    reconcile: ['POST', '/api/reconcile'],
  };
  if (map[cmd] && !target) {
    const [m, p] = map[cmd];
    const r = await api(m, p);
    print(r.body);
    if (r.status >= 400) process.exitCode = 1;
    return;
  }
  if (!target) {
    help();
    process.exitCode = 1;
    return;
  }
  const pathName = instance
    ? `/api/instances/${target}/${cmd}`
    : `/api/services/${target}/${cmd}`;
  const r = await api('POST', pathName);
  print(r.body);
  if (r.status >= 400) process.exitCode = 1;
}

main().catch((err) => {
  print({ error: err.message, hint: 'Is `verae-fleet serve` running?' });
  process.exitCode = 1;
});