/* 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
}

async function evalTest(ctx, args) {
  if (!args.length) return false
  if (args[0] === '!') {
    const inner = await evalTest(ctx, args.slice(1))
    return !inner
  }
  if (args.length === 3) {
    const [a, op, b] = args
    if (op === '-eq' || op === '-ne' || op === '-lt' || op === '-le' || op === '-gt' || op === '-ge') {
      const la = Number.parseInt(String(a), 10)
      const lb = Number.parseInt(String(b), 10)
      if (!Number.isFinite(la) || !Number.isFinite(lb)) return false
      switch (op) {
        case '-eq':
          return la === lb
        case '-ne':
          return la !== lb
        case '-lt':
          return la < lb
        case '-le':
          return la <= lb
        case '-gt':
          return la > lb
        case '-ge':
          return la >= lb
        default:
          return false
      }
    }
    if (op === '=') return a === b
    if (op === '!=') return a !== b
    return false
  }
  if (args.length === 2) {
    const op = args[0]
    const p = args[1]
    if (op === '-h' || op === '-L') {
      const st = await ctx.vfs.lstat(p)
      return st != null && st.type === 'symlink'
    }
    const st = await ctx.vfs.stat(p)
    if (op === '-e' || op === '-a') return st != null
    if (op === '-f') return st != null && st.type === 'file'
    if (op === '-d') return st != null && st.type === 'directory'
    if (op === '-z') return p.length === 0
    if (op === '-n') return p.length > 0
    return false
  }
  if (args.length === 1) return args[0] !== ''
  return false
}

async function run(ctx, argv) {
  ctx.exitCode = (await evalTest(ctx, argv.slice(1))) ? 0 : 1
}