const base = '/srv/proc/', m = {},
qmt = (pid, f) => queueMicrotask(() => { try { f() } catch (e) { req('put', '/srv/cons', pid + ': ' + e + '\n' + (e?.stack ?? '')) } }),
dir = pid => base + pid + '/',
pf = (pid, f, d) => req('put', dir(pid) + f, d),
fail = (pid, e) => { pf(pid, 'err', e + '\n' + (e?.stack ?? '')); pf(pid, 'status', 'err'); throw e },
load = p => { const s = req('put', '/srv/cc', p); try { return (0, eval)('"use strict"; ({ sub, tra }, req, mount) => { ' + s + '\n}\n//# sourceURL=wom:' + p) } catch (e) { err(p + ':' + (req('put', '/srv/parse', s) || e.message)) } },
start = (pid, d, n) => {
  const old = m[pid]; if (old?.del) return err('busy')
  const [s = err('bad request'), ...l] = d.split('\n').filter(Boolean), [p, ...args] = s.split(' '), fn = load(p)
  old && (old.del = 1)
  const cur = m[pid] = { del: 0, ns: Object.fromEntries([...req('get', '/lib/ns').replaceAll('$pid', pid).split('\n'), ...l].map(x => x.split(' ').slice(1).reverse())), args: args.join(' ') }
  n('put', dir(pid) + 'record', d)
  n('put', dir(pid) + 'fs/', '')
  pf(pid, 'status', 'starting')
  qmt(pid, () => {
    old?.c?.dis()
    if (cur.del) return
    try {
      old && (n('del', dir(pid) + 'fs/'), n('put', dir(pid) + 'fs/', ''))
      cur.c = C(({ sub, der, tra }) => fn({ sub: (f, cb, im) => sub(der(f), cb, im), tra }, (v, p, d) => req(v, p, d, cur.ns), (p, h) => tra(globalThis.mount(p, h, cur.ns))))()
      pf(pid, 'status', 'started')
    } catch (e) { fail(pid, e) }
  })
}

req('put', base); mount(base, (v, p, d, n) => {
  const [, pid, ...l] = p.split('/'), rest = l.join('/')
  if (v === 'get' && !pid) {
    const first = id => { try { return ' ' + n('get', dir(id) + 'record').split('\n')[0] } catch { return '' } }
    return n().split('\n').map(s => s.endsWith('/') ? s + first(s.slice(3, -1)) : s).join('\n') + '\n=> new'
  }
  if (v === 'put' && pid === 'new') { const id = 'p' + crypto.randomUUID().slice(0, 8); return start(id, d, n), dir(id) }
  if (v === 'put' && pid && !l[0] && d) return start(pid, d, n)
  if (v === 'del' && pid && !l[0]) {
    if (!m[pid]) return n()
    if (m[pid].del) return
    m[pid].del = 1
    pf(pid, 'status', 'closing')
    qmt(pid, () => { m[pid].c?.dis(); delete m[pid]; req('del', dir(pid)) })
    return
  }
  if (m[pid]) {
    if (!rest) return v !== 'get' ? n() : n() + '\n=> ns\n=> ctl'
    if (rest === 'record' && v !== 'get') err('not allowed')
    if (rest === 'ns') return v !== 'get' ? err('not allowed') : Object.entries(m[pid].ns).map(([k, t]) => '=> ' + t + ' ' + k).join('\n')
    if (rest === 'ctl') return v !== 'put' ? err('not allowed') : d === 'close' ? req('del', dir(pid)) : err('unknown control message "' + (d ?? '') + '"')
    return n()
  }
  return n()
})

req('get', base).split('\n').map(s => s.split(' ')[1]).filter(s => s?.endsWith('/')).forEach(s => {
  const pid = s.slice(0, -1)
  try { req('put', dir(pid), req('get', dir(pid) + 'record')) }
  catch (e) { pf(pid, 'err', e.message); pf(pid, 'status', 'err'); req('put', '/srv/cons', s + ': ' + e.message) }
})