/* BARE_OS_BIN_API 1.0.0 — bump when staged /bin script semantics change (see developer guide). */
/** Shared helpers for drive-resident /bin scripts (prepended before each command). */
function bareStdin(ctx) {
  return typeof ctx.shellStdin === 'string' ? ctx.shellStdin : ''
}

/** @param {number} mode @param {'file' | 'directory' | 'symlink'} type */
function bareFormatModeString(mode, type) {
  const typeChar = type === 'directory' ? 'd' : type === 'symlink' ? 'l' : '-'
  const perm = mode & 0o777
  const r = (bit) => (perm & bit ? 'r' : '-')
  const w = (bit) => (perm & bit ? 'w' : '-')
  const x = (bit) => (perm & bit ? 'x' : '-')
  return (
    typeChar +
    r(0o400) +
    w(0o200) +
    x(0o100) +
    r(0o040) +
    w(0o020) +
    x(0o010) +
    r(0o004) +
    w(0o002) +
    x(0o001)
  )
}

/** @param {number} mtimeMs @param {number} [nowMs] */
function bareFormatLsMtime(mtimeMs, nowMs) {
  const now = nowMs != null ? nowMs : Date.now()
  const d = new Date(mtimeMs)
  const months = [
    'Jan',
    'Feb',
    'Mar',
    'Apr',
    'May',
    'Jun',
    'Jul',
    'Aug',
    'Sep',
    'Oct',
    'Nov',
    'Dec'
  ]
  const mon = months[d.getMonth()]
  const day = String(d.getDate()).padStart(2, ' ')
  const sixMo = 180 * 24 * 3600 * 1000
  if (Math.abs(now - mtimeMs) > sixMo) {
    const yr = String(d.getFullYear()).padStart(4, ' ')
    return mon + ' ' + day + '  ' + yr
  }
  const hh = String(d.getHours()).padStart(2, '0')
  const mm = String(d.getMinutes()).padStart(2, '0')
  return mon + ' ' + day + ' ' + hh + ':' + mm
}

/** @param {number} size */
function barePosixBlocks(size) {
  return Math.ceil(Number(size) / 512) || 0
}

/**
 * Raw stdout for NUL/binary when **`process.stdout.write`** is missing.
 * If **`ctx.bareOsBinWrite(Uint8Array|string)`** is set (tests / host), use it.
 * @param {Record<string, unknown>} ctx
 * @param {string | Uint8Array} chunk
 * @returns {boolean}
 */
function bareOsEmitRaw(ctx, chunk) {
  if (typeof ctx.bareOsBinWrite === 'function') {
    const b4 = ctx.b4a
    const u8 =
      typeof chunk === 'string'
        ? b4 && typeof b4.from === 'function'
          ? b4.from(chunk)
          : new TextEncoder().encode(chunk)
        : chunk
    ctx.bareOsBinWrite(u8 instanceof Uint8Array ? u8 : new Uint8Array(u8))
    return true
  }
  const w = globalThis.process?.stdout?.write
  if (typeof w === 'function') {
    w.call(globalThis.process.stdout, chunk)
    return true
  }
  return false
}

/**
 * Resolve job spec %n / %% to synthetic PID (4100+job.id) for ctx.bareOsSendSignal.
 * Matches fg/wait job selection: %% is latest non-done job.
 * @param {string} raw
 * @param {Record<string, unknown>} ctx
 * @returns {string} numeric pid, pgid negative form, or passthrough token
 */
function bareOsKillResolveTarget(raw, ctx) {
  const s = String(raw == null ? '' : raw).trim()
  if (!s.startsWith('%')) return s
  const list =
    ctx.shellBackgroundJobs &&
    typeof ctx.shellBackgroundJobs === 'object' &&
    Array.isArray(ctx.shellBackgroundJobs.list)
      ? ctx.shellBackgroundJobs.list
      : []
  const spec = s.slice(1)
  if (spec === '%' || spec === '') {
    const running = list.filter((j) => j && !j.done)
    const j = running.length ? running[running.length - 1] : null
    if (!j) throw new Error('kill: no current job')
    return String(4100 + j.id)
  }
  const id = Number.parseInt(spec, 10)
  if (!Number.isFinite(id))
    throw new Error('kill: invalid job specification: ' + raw)
  const j = list.find((x) => x && x.id === id)
  if (!j) throw new Error('kill: %' + id + ': no such job')
  return String(4100 + j.id)
}

async function run(ctx, argv) {
  const args = argv.slice(1)
  let signal = 'TERM'
  /** @type {string[]} */
  const targets = []

  for (let i = 0; i < args.length; i++) {
    const a = args[i]
    if (a === '--') {
      for (let j = i + 1; j < args.length; j++) targets.push(args[j])
      break
    }
    if (a === '-l' || a === '--list') {
      ctx.console.log('HUP INT KILL TERM PIPE CHLD USR1 USR2 0')
      return
    }
    if (a === '-s' || a === '--signal') {
      const n = args[i + 1]
      if (!n) {
        ctx.console.error('kill: option requires an argument: ' + a)
        ctx.exitCode = 1
        return
      }
      signal = n
      i++
      continue
    }
    if (/^-[A-Za-z0-9]+$/.test(a) && a !== '-') {
      signal = a.slice(1)
      continue
    }
    targets.push(a)
  }

  if (targets.length === 0) {
    ctx.console.error(
      'usage: kill [-s SIGNAL | -SIGNAL] <pid|name|%job|%%>...'
    )
    ctx.exitCode = 1
    return
  }
  const send = ctx.bareOsSendSignal
  if (typeof send !== 'function') {
    ctx.console.error('kill: signal API unavailable in this runtime')
    ctx.exitCode = 1
    return
  }

  let failed = 0
  for (const t of targets) {
    try {
      const resolved = bareOsKillResolveTarget(t, ctx)
      send.call(ctx, resolved, signal)
    } catch (e) {
      failed++
      ctx.console.error('kill: ' + t + ': ' + (e?.message || String(e)))
    }
  }
  if (failed > 0) ctx.exitCode = 1
}