/** 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
}

async function run(ctx, argv) {
  const args = argv.slice(1).filter((a) => !a.startsWith('-'))
  let a = 1
  let step = 1
  let b = 1
  if (args.length === 1) {
    b = parseInt(args[0], 10)
  } else if (args.length === 2) {
    a = parseInt(args[0], 10)
    b = parseInt(args[1], 10)
  } else if (args.length >= 3) {
    a = parseInt(args[0], 10)
    step = parseInt(args[1], 10)
    b = parseInt(args[2], 10)
  }
  if (step === 0 || Number.isNaN(a) || Number.isNaN(b) || Number.isNaN(step)) {
    ctx.console.error('seq: invalid arguments')
    ctx.exitCode = 1
    return
  }
  if (step > 0) {
    for (let x = a; x <= b; x += step) ctx.console.log(String(x))
  } else {
    for (let x = a; x >= b; x += step) ctx.console.log(String(x))
  }
}