/* 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
}

/** Session env map (`vfs.env`, then `ctx.env`). Never throws. */
function bareOsEnv(ctx) {
  const v = ctx && ctx.vfs && ctx.vfs.env
  if (v && typeof v === 'object') return v
  const e = ctx && ctx.env
  if (e && typeof e === 'object') return e
  return {}
}

/**
 * Strict POSIX-ish decimal integer (no octal, no exponent, no empty).
 * @param {unknown} s
 * @returns {number}
 */
function bareOsParseDecInt(s) {
  const t = String(s == null ? '' : s).trim()
  if (!/^[+-]?(?:0|[1-9][0-9]*)$/.test(t)) return NaN
  const n = Number.parseInt(t, 10)
  return Number.isSafeInteger(n) ? n : NaN
}

/** @param {unknown} s */
function bareOsParseNonNegInt(s) {
  const n = bareOsParseDecInt(s)
  return n >= 0 ? n : NaN
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {string} name
 * @param {number} fallback
 * @param {number} [min]
 * @param {number} [max]
 */
function bareOsEnvInt(ctx, name, fallback, min, max) {
  const raw = bareOsEnv(ctx)[name]
  if (raw == null || raw === '') return fallback
  const n = Number.parseInt(String(raw), 10)
  if (!Number.isFinite(n)) return fallback
  let v = n
  if (min != null && v < min) v = min
  if (max != null && v > max) v = max
  return v
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {string} msg
 * @param {number} [code]
 */
function bareOsFail(ctx, msg, code) {
  if (msg) ctx.console.error(msg)
  ctx.exitCode = code == null ? 1 : code
}

/** @param {unknown} e */
function bareOsIsNotFoundErr(e) {
  const code = e && typeof e === 'object' ? e.code : ''
  if (code === 'ENOENT') return true
  const msg = String((e && e.message) || e || '')
  return /ENOENT|No such file|not found/i.test(msg)
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {unknown} buf
 * @returns {Uint8Array}
 */
function bareOsToU8(ctx, buf) {
  if (!buf) return new Uint8Array(0)
  if (buf instanceof Uint8Array) return buf
  if (ctx && ctx.b4a && typeof ctx.b4a.from === 'function') return ctx.b4a.from(buf)
  return new Uint8Array(buf)
}

/** @param {string} dir @param {string} name */
function bareOsJoinPath(dir, name) {
  const d = String(dir || '').replace(/\/+$/, '')
  const n = String(name || '').replace(/^\/+/, '')
  if (!d || d === '/') return '/' + n
  return d + '/' + n
}

/** @param {string} p */
function bareOsBaseName(p) {
  const t = String(p || '').replace(/\/+$/, '')
  if (!t || t === '/') return t === '/' ? '/' : ''
  const i = t.lastIndexOf('/')
  return i < 0 ? t : t.slice(i + 1) || t
}

/** @param {string} p */
function bareOsParentDir(p) {
  const t = String(p || '').replace(/\/+$/, '') || '/'
  if (t === '/') return '/'
  const i = t.lastIndexOf('/')
  return i <= 0 ? '/' : t.slice(0, i) || '/'
}

/** @param {string} p */
function bareOsNormPath(p) {
  return String(p || '').replace(/\/+$/, '') || '/'
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {string} p
 */
function bareOsResolvePath(ctx, p) {
  if (ctx && ctx.vfs && typeof ctx.vfs.resolveLogical === 'function') {
    try {
      return String(ctx.vfs.resolveLogical(p) || p)
    } catch {
      /* fall through */
    }
  }
  return String(p || '')
}

/**
 * True when dest is src or lives under src (self-copy / self-move).
 * @param {Record<string, unknown>} ctx
 * @param {string} src
 * @param {string} dest
 */
function bareOsDestInsideSrc(ctx, src, dest) {
  const s = bareOsNormPath(bareOsResolvePath(ctx, src))
  const d = bareOsNormPath(bareOsResolvePath(ctx, dest))
  if (s === d) return true
  if (s === '/') return d !== '/'
  return d === s || d.startsWith(s + '/')
}

const BARE_OS_B64_ALPH =
  'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'

/** @param {Uint8Array} u8 */
function bareOsB64Encode(u8) {
  let out = ''
  let i = 0
  for (; i + 2 < u8.length; i += 3) {
    const n = (u8[i] << 16) | (u8[i + 1] << 8) | u8[i + 2]
    out +=
      BARE_OS_B64_ALPH[(n >> 18) & 63] +
      BARE_OS_B64_ALPH[(n >> 12) & 63] +
      BARE_OS_B64_ALPH[(n >> 6) & 63] +
      BARE_OS_B64_ALPH[n & 63]
  }
  const rest = u8.length - i
  if (rest === 1) {
    const n = u8[i] << 16
    out += BARE_OS_B64_ALPH[(n >> 18) & 63] + BARE_OS_B64_ALPH[(n >> 12) & 63] + '=='
  } else if (rest === 2) {
    const n = (u8[i] << 16) | (u8[i + 1] << 8)
    out +=
      BARE_OS_B64_ALPH[(n >> 18) & 63] +
      BARE_OS_B64_ALPH[(n >> 12) & 63] +
      BARE_OS_B64_ALPH[(n >> 6) & 63] +
      '='
  }
  return out
}

/**
 * RFC 4648 Base64 decode (also accepts URL-safe alphabet). Rejects junk.
 * @param {string} s
 * @returns {Uint8Array}
 */
function bareOsB64Decode(s) {
  const t = String(s).replace(/\s+/g, '')
  if (!t) return new Uint8Array(0)
  if (t.length % 4 === 1) throw new Error('invalid base64 length')
  let pad = 0
  if (t.endsWith('==')) pad = 2
  else if (t.endsWith('=')) pad = 1
  const body = pad ? t.slice(0, t.length - pad) : t
  const bytes = []
  let buf = 0
  let bits = 0
  for (let i = 0; i < body.length; i++) {
    const c = body[i]
    let v = BARE_OS_B64_ALPH.indexOf(c)
    if (v < 0) {
      if (c === '-') v = 62
      else if (c === '_') v = 63
      else throw new Error('invalid base64 character')
    }
    buf = (buf << 6) | v
    bits += 6
    if (bits >= 8) {
      bits -= 8
      bytes.push((buf >> bits) & 255)
    }
  }
  if (pad) {
    const want = Math.floor((body.length * 6) / 8)
    if (bytes.length > want) bytes.length = want
  }
  return new Uint8Array(bytes)
}

/**
 * @param {string} s
 * @returns {Uint8Array}
 */
function bareOsHexDecode(s) {
  const t = String(s).replace(/\s+/g, '')
  if (t.length % 2 !== 0) throw new Error('odd hex length')
  const out = new Uint8Array(t.length / 2)
  for (let i = 0; i < out.length; i++) {
    const pair = t.slice(i * 2, i * 2 + 2)
    if (!/^[0-9a-fA-F]{2}$/.test(pair)) throw new Error('invalid hex')
    out[i] = Number.parseInt(pair, 16)
  }
  return out
}

/** @param {Uint8Array} u8 */
function bareOsHexEncode(u8) {
  let s = ''
  for (let i = 0; i < u8.length; i++) s += u8[i].toString(16).padStart(2, '0')
  return s
}

/** IRC message codec + casemap (modern.ircdocs.horse). No import. */

var BARE_IRC_MAX_LINE = 512
var BARE_IRC_MAX_TAGS = 8191

function bareIrcStripCrlf(s) {
  var t = String(s == null ? '' : s)
  if (t.charAt(t.length - 1) === '\n') t = t.slice(0, -1)
  if (t.charAt(t.length - 1) === '\r') t = t.slice(0, -1)
  return t
}

function bareIrcUnescapeTagValue(v) {
  var s = String(v == null ? '' : v)
  var out = ''
  for (var i = 0; i < s.length; i++) {
    var c = s.charAt(i)
    if (c !== '\\') {
      out += c
      continue
    }
    var n = s.charAt(i + 1)
    if (n === ':') {
      out += ';'
      i++
    } else if (n === 's') {
      out += ' '
      i++
    } else if (n === '\\') {
      out += '\\'
      i++
    } else if (n === 'r') {
      out += '\r'
      i++
    } else if (n === 'n') {
      out += '\n'
      i++
    } else if (n) {
      out += n
      i++
    }
  }
  return out
}

function bareIrcEscapeTagValue(v) {
  var s = String(v == null ? '' : v)
  var out = ''
  for (var i = 0; i < s.length; i++) {
    var c = s.charAt(i)
    if (c === ';') out += '\\:'
    else if (c === ' ') out += '\\s'
    else if (c === '\\') out += '\\\\'
    else if (c === '\r') out += '\\r'
    else if (c === '\n') out += '\\n'
    else out += c
  }
  return out
}

/**
 * @param {string} line
 * @returns {{ tags: Record<string, string>, source: string, nick: string, user: string, host: string, command: string, params: string[] } | null}
 */
function bareIrcParseMessage(line) {
  var raw = bareIrcStripCrlf(line)
  if (!raw) return null
  var tags = {}
  var i = 0
  if (raw.charAt(0) === '@') {
    var sp = raw.indexOf(' ')
    if (sp < 0) return null
    var tagStr = raw.slice(1, sp)
    i = sp + 1
    while (i < raw.length && raw.charAt(i) === ' ') i++
    var parts = tagStr.split(';')
    for (var t = 0; t < parts.length; t++) {
      var item = parts[t]
      if (!item) continue
      var eq = item.indexOf('=')
      if (eq < 0) tags[item] = ''
      else tags[item.slice(0, eq)] = bareIrcUnescapeTagValue(item.slice(eq + 1))
    }
    raw = raw.slice(i)
    i = 0
  }
  var source = ''
  var nick = ''
  var user = ''
  var host = ''
  if (raw.charAt(0) === ':') {
    var sp2 = raw.indexOf(' ')
    if (sp2 < 0) return null
    source = raw.slice(1, sp2)
    raw = raw.slice(sp2 + 1)
    while (raw.charAt(0) === ' ') raw = raw.slice(1)
    var bang = source.indexOf('!')
    var at = source.indexOf('@')
    if (bang >= 0) {
      nick = source.slice(0, bang)
      if (at > bang) {
        user = source.slice(bang + 1, at)
        host = source.slice(at + 1)
      } else user = source.slice(bang + 1)
    } else if (at >= 0) {
      nick = source.slice(0, at)
      host = source.slice(at + 1)
    } else nick = source
  }
  while (raw.charAt(0) === ' ') raw = raw.slice(1)
  var cmdEnd = raw.indexOf(' ')
  var command
  var rest
  if (cmdEnd < 0) {
    command = raw
    rest = ''
  } else {
    command = raw.slice(0, cmdEnd)
    rest = raw.slice(cmdEnd + 1)
  }
  if (!command) return null
  var params = []
  while (rest.length) {
    while (rest.charAt(0) === ' ') rest = rest.slice(1)
    if (!rest) break
    if (rest.charAt(0) === ':') {
      params.push(rest.slice(1))
      break
    }
    var nsp = rest.indexOf(' ')
    if (nsp < 0) {
      params.push(rest)
      break
    }
    params.push(rest.slice(0, nsp))
    rest = rest.slice(nsp + 1)
  }
  return {
    tags: tags,
    source: source,
    nick: nick,
    user: user,
    host: host,
    command: command,
    params: params
  }
}

/**
 * @param {{ tags?: Record<string, string>, source?: string, command: string, params?: string[] }} msg
 */
function bareIrcSerializeMessage(msg) {
  var m = msg || {}
  var out = ''
  var tags = m.tags
  if (tags && typeof tags === 'object') {
    var keys = []
    var k
    for (k in tags) {
      if (Object.prototype.hasOwnProperty.call(tags, k)) keys.push(k)
    }
    if (keys.length) {
      out += '@'
      for (var i = 0; i < keys.length; i++) {
        if (i) out += ';'
        var val = tags[keys[i]]
        if (val == null || val === '') out += keys[i]
        else out += keys[i] + '=' + bareIrcEscapeTagValue(val)
      }
      out += ' '
    }
  }
  if (m.source) out += ':' + m.source + ' '
  out += String(m.command || '')
  var params = Array.isArray(m.params) ? m.params : []
  for (var p = 0; p < params.length; p++) {
    var part = String(params[p] == null ? '' : params[p])
    var last = p === params.length - 1
    if (last) {
      out += ' :' + part
    } else {
      out += ' ' + part
    }
  }
  return out + '\r\n'
}

/**
 * Byte/string accumulator. Returns complete lines without the delimiter.
 */
function bareIrcCreateLineBuffer() {
  var acc = ''
  return {
    push: function (chunk) {
      if (chunk == null) return []
      var s
      if (typeof chunk === 'string') s = chunk
      else if (typeof TextDecoder !== 'undefined') {
        s = new TextDecoder('utf-8', { fatal: false }).decode(
          chunk instanceof Uint8Array ? chunk : new Uint8Array(chunk)
        )
      } else {
        var u = chunk instanceof Uint8Array ? chunk : []
        s = ''
        for (var i = 0; i < u.length; i++) s += String.fromCharCode(u[i])
      }
      acc += s.replace(/\r\n/g, '\n').replace(/\r/g, '\n')
      var out = []
      for (;;) {
        var n = acc.indexOf('\n')
        if (n < 0) break
        var line = acc.slice(0, n)
        acc = acc.slice(n + 1)
        if (line) out.push(line)
      }
      return out
    },
    pending: function () {
      return acc
    }
  }
}

function bareIrcRfc1459LowerChar(c) {
  var code = c.charCodeAt(0)
  if (code >= 65 && code <= 90) return String.fromCharCode(code + 32)
  if (c === '[') return '{'
  if (c === ']') return '}'
  if (c === '\\') return '|'
  if (c === '~') return '^'
  return c
}

function bareIrcCasemap(s, mapping) {
  var t = String(s == null ? '' : s)
  var kind = String(mapping || 'rfc1459').toLowerCase()
  if (kind === 'ascii') return t.toLowerCase()
  var out = ''
  for (var i = 0; i < t.length; i++) out += bareIrcRfc1459LowerChar(t.charAt(i))
  return out
}

function bareIrcEqual(a, b, mapping) {
  return bareIrcCasemap(a, mapping) === bareIrcCasemap(b, mapping)
}

function bareIrcIsChannel(name, chantypes) {
  var n = String(name || '')
  if (!n) return false
  var types = chantypes || '#'
  return types.indexOf(n.charAt(0)) >= 0
}

/** RPL_ISUPPORT (005) token map. */

function bareIrcParseIsupport(params) {
  var tokens = {}
  var list = Array.isArray(params) ? params : []
  var last = list.length
  if (last && String(list[last - 1]).indexOf('are supported') >= 0) last--
  var start = 0
  if (
    list.length &&
    !/=/.test(String(list[0])) &&
    !/^[A-Z]+$/.test(String(list[0]))
  ) {
    start = 1
  }
  for (var i = start; i < last; i++) {
    var raw = String(list[i] || '')
    if (!raw) continue
    var eq = raw.indexOf('=')
    if (eq < 0) tokens[raw] = true
    else tokens[raw.slice(0, eq)] = raw.slice(eq + 1)
  }
  return tokens
}

function bareIrcIsupportDefaults() {
  return {
    CASEMAPPING: 'rfc1459',
    CHANTYPES: '#&',
    PREFIX: '(ov)@+',
    NICKLEN: '16',
    CHANNELLEN: '50',
    TOPICLEN: '390',
    NETWORK: ''
  }
}

function bareIrcMergeIsupport(cur, incoming) {
  var out = cur && typeof cur === 'object' ? cur : bareIrcIsupportDefaults()
  var next = incoming && typeof incoming === 'object' ? incoming : {}
  var k
  for (k in next) {
    if (Object.prototype.hasOwnProperty.call(next, k)) out[k] = next[k]
  }
  return out
}

function bareIrcPrefixMap(isupport) {
  var raw =
    isupport && isupport.PREFIX != null ? String(isupport.PREFIX) : '(ov)@+'
  var m = /^\(([^)]+)\)(.*)$/.exec(raw)
  var modes = m ? m[1] : 'ov'
  var prefs = m ? m[2] : '@+'
  var byMode = {}
  var byPref = {}
  var i
  for (i = 0; i < modes.length && i < prefs.length; i++) {
    byMode[modes.charAt(i)] = prefs.charAt(i)
    byPref[prefs.charAt(i)] = modes.charAt(i)
  }
  return { modes: modes, prefixes: prefs, byMode: byMode, byPref: byPref }
}

function bareIrcNicklen(isupport) {
  var n = parseInt(isupport && isupport.NICKLEN, 10)
  return Number.isFinite(n) && n > 0 ? n : 16
}

function bareIrcChantypes(isupport) {
  return (isupport && isupport.CHANTYPES) || '#'
}

function bareIrcCasemapping(isupport) {
  return (isupport && isupport.CASEMAPPING) || 'rfc1459'
}

/** SASL PLAIN (IRCv3). No import. */

function bareIrcB64Encode(bytes) {
  var table = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
  var s = ''
  var i = 0
  while (i < bytes.length) {
    var a = bytes[i++]
    var b = i < bytes.length ? bytes[i++] : NaN
    var c = i < bytes.length ? bytes[i++] : NaN
    var triple =
      ((a & 255) << 16) |
      ((Number.isFinite(b) ? b & 255 : 0) << 8) |
      (Number.isFinite(c) ? c & 255 : 0)
    s += table.charAt((triple >> 18) & 63)
    s += table.charAt((triple >> 12) & 63)
    s += Number.isFinite(b) ? table.charAt((triple >> 6) & 63) : '='
    s += Number.isFinite(c) ? table.charAt(triple & 63) : '='
  }
  return s
}

function bareIrcUtf8Bytes(str) {
  var s = String(str == null ? '' : str)
  if (typeof TextEncoder !== 'undefined')
    return Array.from(new TextEncoder().encode(s))
  var out = []
  for (var i = 0; i < s.length; i++) out.push(s.charCodeAt(i) & 255)
  return out
}

/**
 * AUTHENTICATE PLAIN payload (account \0 account \0 password), chunked ≤400.
 * @returns {string[]}
 */
function bareIrcSaslPlainChunks(user, pass) {
  var u = String(user || '')
  var p = String(pass || '')
  var raw = bareIrcUtf8Bytes('\0' + u + '\0' + p)
  var b64 = bareIrcB64Encode(raw)
  var chunks = []
  var i = 0
  if (!b64) return ['+']
  while (i < b64.length) {
    chunks.push(b64.slice(i, i + 400))
    i += 400
  }
  return chunks
}

/** IRC session buffers and members. */

var BARE_IRC_MAX_TRANSCRIPT = 2000

function bareIrcCreateState(opts) {
  opts = opts || {}
  var max =
    opts.maxTranscript > 0 ? opts.maxTranscript : BARE_IRC_MAX_TRANSCRIPT
  return {
    connection: 'idle',
    nick: opts.nick || '',
    requestedNick: opts.nick || '',
    account: '',
    away: false,
    network: opts.network || '',
    isupport: bareIrcIsupportDefaults(),
    capsOffered: {},
    capsEnabled: {},
    buffers: {},
    currentId: 'server',
    maxTranscript: max,
    registered: false,
    tls: opts.tls !== false,
    saslOk: false,
    channelList: [],
    listBusy: false,
    ignore: {}
  }
}

function bareIrcBufferId(kind, name, mapping) {
  if (kind === 'server') return 'server'
  return kind + ':' + bareIrcCasemap(name, mapping)
}

function bareIrcEnsureBuffer(state, kind, name) {
  var mapping = bareIrcCasemapping(state.isupport)
  var id = bareIrcBufferId(kind, name, mapping)
  if (!state.buffers[id]) {
    state.buffers[id] = {
      id: id,
      kind: kind,
      name: name || '*server',
      topic: '',
      members: {},
      lines: [],
      unread: 0,
      highlight: false
    }
  }
  return state.buffers[id]
}

function bareIrcPushLine(state, buf, rec) {
  if (!buf) return
  buf.lines.push(rec)
  while (buf.lines.length > state.maxTranscript) buf.lines.shift()
  if (buf.id !== state.currentId) {
    buf.unread++
    if (rec && rec.highlight) buf.highlight = true
  }
}

function bareIrcListBuffers(state) {
  var ids = Object.keys(state.buffers)
  ids.sort(function (a, b) {
    if (a === 'server') return -1
    if (b === 'server') return 1
    return a < b ? -1 : a > b ? 1 : 0
  })
  return ids.map(function (id) {
    return state.buffers[id]
  })
}

function bareIrcMemberPrefixes(state, nickRaw) {
  var pref = bareIrcPrefixMap(state.isupport)
  var nick = String(nickRaw || '')
  var modes = ''
  while (nick && pref.byPref[nick.charAt(0)]) {
    modes += pref.byPref[nick.charAt(0)]
    nick = nick.slice(1)
  }
  return { nick: nick, modes: modes }
}

/** Libera defaults + ~/.irc config/secrets. */

function bareIrcRandomSuffix(n) {
  var alphabet = 'abcdefghijkmnpqrstuvwxyz23456789'
  var out = ''
  var i
  var len = n > 0 ? n : 4
  for (i = 0; i < len; i++) {
    out += alphabet.charAt(Math.floor(Math.random() * alphabet.length))
  }
  return out
}

function bareIrcRandomNick() {
  return ('os' + bareIrcRandomSuffix(5)).slice(0, 16)
}

function bareIrcNickLooksMachine(nick) {
  var s = String(nick || '')
  if (!s) return true
  if (/^[0-9a-f]{8,16}$/i.test(s)) return true
  if (/^[0-9a-f]{12}$/i.test(s)) return true
  if (/^[a-z0-9]{10,}-[a-z0-9]{4,}$/i.test(s)) return true
  return false
}

function bareIrcHostLooksLibera(host) {
  var h = String(host || '')
    .trim()
    .toLowerCase()
  return h === 'libera.chat' || h.endsWith('.libera.chat')
}

var BARE_IRC_LIBERA = {
  name: 'libera',
  host: 'irc.libera.chat',
  port: 6697,
  tls: true,
  regional: {
    eu: 'irc.eu.libera.chat',
    us: 'irc.us.libera.chat',
    au: 'irc.au.libera.chat',
    ea: 'irc.ea.libera.chat',
    ipv4: 'irc.ipv4.libera.chat',
    ipv6: 'irc.ipv6.libera.chat'
  }
}

function bareIrcHome(ctx) {
  var env = ctx && ctx.env && typeof ctx.env === 'object' ? ctx.env : {}
  if (env.HOME) return String(env.HOME)
  if (typeof ctx.bareOsResolveHome === 'function') {
    try {
      return String(ctx.bareOsResolveHome() || '')
    } catch (e) {
      /* ignore */
    }
  }
  return '/home/guest'
}

function bareIrcConfigPaths(ctx) {
  var home = bareIrcHome(ctx).replace(/\/+$/, '')
  return {
    dir: home + '/.irc',
    config: home + '/.irc/config.json',
    secrets: home + '/.irc/secrets.json',
    bindings: home + '/.irc/bindings.json'
  }
}

function bareIrcReadJsonFile(ctx, path) {
  if (!ctx || !ctx.vfs || typeof ctx.vfs.readFile !== 'function') return null
  try {
    var buf = ctx.vfs.readFile(path)
    if (buf && typeof buf.then === 'function') return buf
    if (!buf) return null
    var t =
      ctx.b4a && typeof ctx.b4a.toString === 'function'
        ? ctx.b4a.toString(buf)
        : String(buf)
    t = String(t || '').trim()
    if (!t) return null
    return JSON.parse(t)
  } catch (e) {
    return null
  }
}

async function bareIrcLoadConfig(ctx) {
  var paths = bareIrcConfigPaths(ctx)
  var raw = bareIrcReadJsonFile(ctx, paths.config)
  if (raw && typeof raw.then === 'function') {
    try {
      var buf = await raw
      if (!buf) raw = null
      else {
        var t =
          ctx.b4a && typeof ctx.b4a.toString === 'function'
            ? ctx.b4a.toString(buf)
            : String(buf)
        raw = t && String(t).trim() ? JSON.parse(String(t).trim()) : null
      }
    } catch (e) {
      raw = null
    }
  }
  var sec = bareIrcReadJsonFile(ctx, paths.secrets)
  if (sec && typeof sec.then === 'function') {
    try {
      var sb = await sec
      if (!sb) sec = null
      else {
        var st =
          ctx.b4a && typeof ctx.b4a.toString === 'function'
            ? ctx.b4a.toString(sb)
            : String(sb)
        sec = st && String(st).trim() ? JSON.parse(String(st).trim()) : null
      }
    } catch (e2) {
      sec = null
    }
  }
  return {
    paths: paths,
    config: raw && typeof raw === 'object' ? raw : {},
    secrets: sec && typeof sec === 'object' ? sec : {}
  }
}

function bareIrcResolveConnect(ctx, flags, loaded) {
  var env = ctx && ctx.env && typeof ctx.env === 'object' ? ctx.env : {}
  var cfg = (loaded && loaded.config) || {}
  var sec = (loaded && loaded.secrets) || {}
  var servers = Array.isArray(cfg.servers) ? cfg.servers : []
  var named = flags.network || flags.host || ''
  var srv = servers[0] || {}
  if (named) {
    for (var i = 0; i < servers.length; i++) {
      if (servers[i] && servers[i].name === named) srv = servers[i]
    }
    if (named === 'libera' || named === 'irc.libera.chat') {
      srv = Object.assign({}, BARE_IRC_LIBERA, srv)
    } else if (BARE_IRC_LIBERA.regional[named]) {
      srv = Object.assign({}, BARE_IRC_LIBERA, srv, {
        host: BARE_IRC_LIBERA.regional[named]
      })
    }
  }
  var host = flags.host || srv.host || BARE_IRC_LIBERA.host
  if (host === 'libera') host = BARE_IRC_LIBERA.host
  var port = flags.port != null ? flags.port : srv.port || BARE_IRC_LIBERA.port
  var tls = flags.tls != null ? flags.tls : srv.tls !== false
  var nick = flags.nick || cfg.nick || env.BARE_IRC_NICK || ''
  var generatedNick = false
  if (!nick) {
    var candidate = env.USER || env.LOGNAME || ''
    if (candidate && !bareIrcNickLooksMachine(candidate)) nick = candidate
  }
  if (!nick) {
    nick = bareIrcRandomNick()
    generatedNick = true
  }
  var saslUser = flags.saslUser || cfg.saslUser || sec.saslUser || ''
  var saslPass = flags.saslPass != null ? flags.saslPass : sec.saslPass || ''
  var autojoin = Array.isArray(flags.autojoin)
    ? flags.autojoin
    : Array.isArray(cfg.autojoin)
      ? cfg.autojoin
      : []
  return {
    host: host,
    port: port,
    tls: tls,
    insecurePlain: !!flags.insecurePlain,
    nick: String(nick).slice(0, 16),
    generatedNick: generatedNick,
    username: flags.username || cfg.username || 'bareos',
    realname: flags.realname || cfg.realname || 'Bare OS irc',
    pass: flags.pass || sec.serverPass || '',
    saslUser: saslUser,
    saslPass: saslPass,
    autojoin: autojoin,
    shareChannels: cfg.shareChannels === true,
    network: srv.name || (bareIrcHostLooksLibera(host) ? 'libera' : host)
  }
}

function bareIrcParseFlags(argv) {
  var args = argv.slice(1)
  var flags = {
    help: false,
    json: false,
    tls: null,
    insecurePlain: false,
    host: '',
    port: null,
    nick: '',
    saslUser: '',
    network: '',
    rest: []
  }
  for (var i = 0; i < args.length; i++) {
    var a = args[i]
    if (a === '-h' || a === '--help') flags.help = true
    else if (a === '--json') flags.json = true
    else if (a === '--tls') flags.tls = true
    else if (a === '--plain') flags.tls = false
    else if (a === '--insecure-plain') flags.insecurePlain = true
    else if (a === '--host' && args[i + 1]) flags.host = args[++i]
    else if (a === '--port' && args[i + 1]) flags.port = parseInt(args[++i], 10)
    else if (a === '--nick' && args[i + 1]) flags.nick = args[++i]
    else if (a === '--sasl-user' && args[i + 1]) flags.saslUser = args[++i]
    else if (a === '--network' && args[i + 1]) flags.network = args[++i]
    else if (a && a.charAt(0) !== '-') flags.rest.push(a)
  }
  if (flags.rest[0] && !flags.host && !flags.network) {
    var r0 = flags.rest[0]
    if (
      r0 === 'libera' ||
      r0 === 'eu' ||
      r0 === 'us' ||
      r0 === 'au' ||
      r0 === 'ea' ||
      r0.indexOf('.') >= 0
    ) {
      flags.network = r0
      flags.rest = flags.rest.slice(1)
    }
  }
  return flags
}

async function bareIrcRememberNick(ctx, nick) {
  var n = String(nick || '').trim()
  if (!n) return false
  if (!ctx || !ctx.vfs || typeof ctx.vfs.writeFile !== 'function') return false
  var paths = bareIrcConfigPaths(ctx)
  var loaded = await bareIrcLoadConfig(ctx)
  var cfg = loaded.config || {}
  if (cfg.nick) return false
  cfg.nick = n
  try {
    if (typeof ctx.vfs.mkdir === 'function') {
      var mk = ctx.vfs.mkdir(paths.dir, { recursive: true })
      if (mk && typeof mk.then === 'function') await mk
    }
    var body = JSON.stringify(cfg, null, 2)
    var w = ctx.vfs.writeFile(paths.config, body)
    if (w && typeof w.then === 'function') await w
    return true
  } catch (e) {
    return false
  }
}

/** IRC connection + registration + dispatch (modern client protocol). */

var BARE_IRC_WANT_CAPS = [
  'cap-notify',
  'multi-prefix',
  'extended-join',
  'account-tag',
  'account-notify',
  'away-notify',
  'chghost',
  'server-time',
  'message-tags',
  'echo-message',
  'sasl'
]

function bareIrcNow() {
  return Date.now()
}

function bareIrcCreateClient(opts) {
  opts = opts || {}
  var listeners = {}
  var sock = null
  var lines = bareIrcCreateLineBuffer()
  var sendTimes = []
  var nickTries = 0
  var capLsDone = false
  var awaitingCapAck = false
  var saslPending = false
  var client = {
    opts: opts,
    state: bareIrcCreateState(opts),
    on: function (ev, fn) {
      if (!listeners[ev]) listeners[ev] = []
      listeners[ev].push(fn)
      return client
    },
    off: function (ev, fn) {
      var arr = listeners[ev]
      if (!arr) return
      listeners[ev] = arr.filter(function (x) {
        return x !== fn
      })
    }
  }

  function emit(ev, payload) {
    var arr = listeners[ev] || []
    for (var i = 0; i < arr.length; i++) {
      try {
        arr[i](payload)
      } catch (e) {
        /* ignore */
      }
    }
    if (typeof opts.onEvent === 'function') {
      try {
        opts.onEvent(ev, payload)
      } catch (e2) {
        /* ignore */
      }
    }
  }

  function writeRaw(s) {
    if (!sock || typeof sock.write !== 'function') return false
    try {
      sock.write(s)
      return true
    } catch (e) {
      return false
    }
  }

  client.sendRaw = function (command, params) {
    var msg =
      typeof command === 'string' && params
        ? { command: command, params: params }
        : typeof command === 'object'
          ? command
          : { command: String(command || ''), params: [] }
    var line = bareIrcSerializeMessage(msg)
    return writeRaw(line)
  }

  client.rateOk = function () {
    var now = bareIrcNow()
    sendTimes = sendTimes.filter(function (t) {
      return now - t < 1000
    })
    if (sendTimes.length >= 5) return false
    sendTimes.push(now)
    return true
  }

  client.sendPrivmsg = function (target, text) {
    if (!client.rateOk()) return false
    var ok = client.sendRaw('PRIVMSG', [target, text])
    if (ok && !client.state.capsEnabled['echo-message']) {
      client._ingestLocalEcho(target, text)
    }
    return ok
  }

  client.join = function (chan, key) {
    return client.sendRaw('JOIN', key ? [chan, key] : [chan])
  }

  client.list = function (pattern) {
    client.state.channelList = []
    client.state.listBusy = true
    var pat = String(pattern || '').trim()
    if (pat && pat.indexOf('*') < 0 && pat.charAt(0) !== '#')
      pat = '*' + pat + '*'
    return client.sendRaw('LIST', pat ? [pat] : [])
  }

  client.part = function (chan, reason) {
    return client.sendRaw('PART', reason ? [chan, reason] : [chan])
  }

  client.quit = function (reason) {
    client.state.connection = 'closing'
    client.sendRaw('QUIT', [reason || 'Leaving'])
    try {
      if (sock && typeof sock.end === 'function') sock.end()
    } catch (e) {
      /* ignore */
    }
  }

  client._ingestLocalEcho = function (target, text) {
    var mapping = bareIrcCasemapping(client.state.isupport)
    var kind = bareIrcIsChannel(target, bareIrcChantypes(client.state.isupport))
      ? 'channel'
      : 'query'
    var buf = bareIrcEnsureBuffer(client.state, kind, target)
    bareIrcPushLine(client.state, buf, {
      atMs: bareIrcNow(),
      kind: 'privmsg',
      from: client.state.nick,
      text: text,
      local: true
    })
    emit('privmsg', {
      target: target,
      nick: client.state.nick,
      text: text,
      local: true
    })
  }

  function requestCaps() {
    var offered = client.state.capsOffered
    var want = []
    for (var i = 0; i < BARE_IRC_WANT_CAPS.length; i++) {
      var c = BARE_IRC_WANT_CAPS[i]
      if (offered[c] != null) want.push(c)
    }
    if (!want.length) {
      finishCap()
      return
    }
    awaitingCapAck = true
    client.sendRaw('CAP', ['REQ', want.join(' ')])
  }

  function finishCap() {
    awaitingCapAck = false
    if (
      client.state.capsEnabled.sasl &&
      opts.saslUser &&
      opts.saslPass != null &&
      String(opts.saslPass) !== ''
    ) {
      saslPending = true
      client.sendRaw('AUTHENTICATE', ['PLAIN'])
      return
    }
    client.sendRaw('CAP', ['END'])
  }

  function applyCapList(text, ack) {
    var bits = String(text || '').split(/\s+/)
    for (var i = 0; i < bits.length; i++) {
      if (!bits[i]) continue
      var name = bits[i]
      var val = true
      var eq = name.indexOf('=')
      if (eq >= 0) {
        val = name.slice(eq + 1)
        name = name.slice(0, eq)
      }
      client.state.capsOffered[name] = val
      if (ack) client.state.capsEnabled[name] = val
    }
  }

  function handleNumeric(msg) {
    var n = parseInt(msg.command, 10)
    var p = msg.params || []
    if (n === 1) {
      if (p[0]) client.state.nick = p[0]
      client.state.registered = true
      client.state.connection = 'registered'
      emit('registered', { nick: client.state.nick })
    } else if (n === 5) {
      client.state.isupport = bareIrcMergeIsupport(
        client.state.isupport,
        bareIrcParseIsupport(p)
      )
      if (client.state.isupport.NETWORK) {
        client.state.network = String(client.state.isupport.NETWORK)
      }
    } else if (n === 332) {
      var ch = p[1] || p[0]
      var buf = bareIrcEnsureBuffer(client.state, 'channel', ch)
      buf.topic = p[p.length - 1] || ''
    } else if (n === 353) {
      var chan = p.length >= 3 ? p[p.length - 2] : p[1]
      var names = String(p[p.length - 1] || '').split(/\s+/)
      var b = bareIrcEnsureBuffer(client.state, 'channel', chan)
      for (var i = 0; i < names.length; i++) {
        if (!names[i]) continue
        var mem = bareIrcMemberPrefixes(client.state, names[i])
        b.members[
          bareIrcCasemap(mem.nick, bareIrcCasemapping(client.state.isupport))
        ] = mem
      }
    } else if (n === 366) {
      emit('names', { channel: p[1] || p[0] })
    } else if (n === 321) {
      client.state.channelList = []
      client.state.listBusy = true
      emit('liststart', {})
    } else if (n === 322) {
      var types = bareIrcChantypes(client.state.isupport)
      var lchan = p[1] || ''
      var lcount = parseInt(p[2], 10)
      var ltopic = p[p.length - 1] || ''
      if (!bareIrcIsChannel(lchan, types) && bareIrcIsChannel(p[0], types)) {
        lchan = p[0]
        lcount = parseInt(p[1], 10)
      }
      if (bareIrcIsChannel(lchan, types)) {
        if (!client.state.channelList) client.state.channelList = []
        if (client.state.channelList.length < 400) {
          client.state.channelList.push({
            name: lchan,
            users: Number.isFinite(lcount) ? lcount : 0,
            topic: ltopic
          })
        }
      }
      emit('list', { channel: lchan, users: lcount, topic: ltopic })
    } else if (n === 323) {
      client.state.listBusy = false
      if (client.state.channelList) {
        client.state.channelList.sort(function (a, b) {
          return (b.users || 0) - (a.users || 0)
        })
      }
      emit('listend', { count: (client.state.channelList || []).length })
    } else if (n === 376 || n === 422) {
      emit('motd_end', {})
    } else if (n === 433) {
      nickTries++
      if (nickTries <= 8) {
        var base = String(
          opts.nick || client.state.requestedNick || 'os'
        ).replace(/_+$/, '')
        var next = (base.slice(0, 10) + '_' + bareIrcRandomSuffix(3)).slice(
          0,
          16
        )
        client.state.requestedNick = next
        client.sendRaw('NICK', [next])
      } else emit('nickinuse', { nick: p[1] || p[0] })
    } else if (n === 470) {
      var fromCh = p[1] || ''
      var toCh = p[2] || ''
      if (toCh) {
        var fb = bareIrcEnsureBuffer(client.state, 'channel', toCh)
        client.state.currentId = fb.id
        bareIrcPushLine(client.state, fb, {
          atMs: bareIrcNow(),
          kind: 'info',
          text: 'forwarded ' + fromCh + ' → ' + toCh
        })
      }
      emit('forward', { from: fromCh, to: toCh })
    } else if (n === 900 || n === 903) {
      client.state.saslOk = true
      if (p.length >= 3) client.state.account = String(p[2] || p[0] || '')
      if (saslPending) {
        saslPending = false
        client.sendRaw('CAP', ['END'])
      }
      emit('sasl', { ok: true })
    } else if (n === 904 || n === 905 || n === 906 || n === 907) {
      client.state.saslOk = false
      if (saslPending) {
        saslPending = false
        client.sendRaw('CAP', ['END'])
      }
      emit('sasl', { ok: false, numeric: n })
    }
    if (n !== 321 && n !== 322 && n !== 323 && n !== 353 && n !== 366) {
      var srv = bareIrcEnsureBuffer(client.state, 'server', '*server')
      bareIrcPushLine(client.state, srv, {
        atMs: bareIrcNow(),
        kind: 'numeric',
        command: msg.command,
        text: (p.slice(1).join(' ') || p.join(' ')).trim()
      })
    }
  }

  function handlePrivmsg(msg, notice) {
    var target = msg.params[0] || ''
    var text = msg.params[1] || ''
    var from = msg.nick || msg.source || ''
    var mapping = bareIrcCasemapping(client.state.isupport)
    if (
      from &&
      client.state.ignore &&
      client.state.ignore[bareIrcCasemap(from, mapping)]
    ) {
      return
    }
    var types = bareIrcChantypes(client.state.isupport)
    var kind
    var name
    if (bareIrcIsChannel(target, types)) {
      kind = 'channel'
      name = target
    } else {
      kind = 'query'
      name = bareIrcEqual(target, client.state.nick, mapping) ? from : target
    }
    var buf = bareIrcEnsureBuffer(client.state, kind, name)
    var ctcp = /^\x01([A-Z]+)(?: ([\s\S]*))?\x01$/.exec(text)
    var rec = {
      atMs: bareIrcNow(),
      kind: notice
        ? 'notice'
        : ctcp && ctcp[1] === 'ACTION'
          ? 'action'
          : 'privmsg',
      from: from,
      text: ctcp && ctcp[1] === 'ACTION' ? ctcp[2] || '' : text,
      highlight: false,
      tags: msg.tags
    }
    var self = client.state.nick
    if (
      self &&
      !notice &&
      rec.kind === 'privmsg' &&
      text.toLowerCase().indexOf(String(self).toLowerCase()) >= 0
    ) {
      rec.highlight = true
    }
    bareIrcPushLine(client.state, buf, rec)
    emit(notice ? 'notice' : 'privmsg', {
      target: target,
      nick: from,
      text: rec.text,
      action: rec.kind === 'action',
      tags: msg.tags
    })
    if (ctcp && !notice && ctcp[1] === 'VERSION') {
      client.sendRaw('NOTICE', [from, '\x01VERSION Bare OS irc\x01'])
    } else if (ctcp && !notice && ctcp[1] === 'PING') {
      client.sendRaw('NOTICE', [from, text])
    }
  }

  client.handleMessage = function (msg) {
    if (!msg || !msg.command) return
    emit('message', msg)
    var cmd = String(msg.command).toUpperCase()
    if (cmd === 'PING') {
      client.sendRaw('PONG', [msg.params[0] || ''])
      emit('ping', msg.params[0])
      return
    }
    if (cmd === 'PONG') return
    if (cmd === 'CAP') {
      var sub = String(msg.params[1] || msg.params[0] || '').toUpperCase()
      var payload = msg.params[msg.params.length - 1] || ''
      if (sub === 'LS') {
        applyCapList(payload, false)
        var more = msg.params[2] === '*' || msg.params[1] === '*'
        if (!more) {
          capLsDone = true
          requestCaps()
        }
      } else if (sub === 'ACK') {
        applyCapList(payload, true)
        if (awaitingCapAck) finishCap()
      } else if (sub === 'NAK') {
        if (awaitingCapAck) finishCap()
      } else if (sub === 'NEW') applyCapList(payload, false)
      return
    }
    if (cmd === 'AUTHENTICATE') {
      if (String(msg.params[0] || '') === '+' && saslPending) {
        var chunks = bareIrcSaslPlainChunks(opts.saslUser, opts.saslPass)
        for (var c = 0; c < chunks.length; c++)
          client.sendRaw('AUTHENTICATE', [chunks[c]])
      }
      return
    }
    if (/^\d{3}$/.test(cmd)) {
      handleNumeric(msg)
      return
    }
    if (cmd === 'PRIVMSG') {
      handlePrivmsg(msg, false)
      return
    }
    if (cmd === 'NOTICE') {
      handlePrivmsg(msg, true)
      return
    }
    if (cmd === 'JOIN') {
      var jc = msg.params[0] || ''
      var jb = bareIrcEnsureBuffer(client.state, 'channel', jc)
      var jm = bareIrcMemberPrefixes(client.state, msg.nick || '')
      var jmap = bareIrcCasemapping(client.state.isupport)
      if (jm.nick) {
        jb.members[bareIrcCasemap(jm.nick, jmap)] = jm
      }
      var selfJoin = bareIrcEqual(msg.nick || '', client.state.nick, jmap)
      if (selfJoin) {
        client.state.currentId = jb.id
        bareIrcPushLine(client.state, jb, {
          atMs: bareIrcNow(),
          kind: 'info',
          text: 'joined ' + jc
        })
      } else {
        bareIrcPushLine(client.state, jb, {
          atMs: bareIrcNow(),
          kind: 'info',
          text: (msg.nick || '') + ' joined'
        })
      }
      emit('join', { channel: jc, nick: msg.nick, self: selfJoin })
      return
    }
    if (cmd === 'TOPIC') {
      var tc = msg.params[0] || ''
      var tb = bareIrcEnsureBuffer(client.state, 'channel', tc)
      tb.topic = msg.params[1] || ''
      bareIrcPushLine(client.state, tb, {
        atMs: bareIrcNow(),
        kind: 'info',
        text: (msg.nick || 'topic') + ': ' + tb.topic
      })
      emit('topic', { channel: tc, topic: tb.topic, nick: msg.nick })
      return
    }
    if (cmd === 'INVITE') {
      var invTo = msg.params[1] || ''
      var srvI = bareIrcEnsureBuffer(client.state, 'server', '*server')
      bareIrcPushLine(client.state, srvI, {
        atMs: bareIrcNow(),
        kind: 'info',
        text:
          (msg.nick || '') +
          ' invited you to ' +
          invTo +
          '  (/join ' +
          invTo +
          ')'
      })
      emit('invite', { nick: msg.nick, channel: invTo })
      return
    }
    if (cmd === 'PART' || cmd === 'KICK') {
      var pc = msg.params[0] || ''
      var pb =
        client.state.buffers[
          bareIrcBufferId(
            'channel',
            pc,
            bareIrcCasemapping(client.state.isupport)
          )
        ]
      var who = cmd === 'KICK' ? msg.params[1] : msg.nick
      if (pb && who) {
        delete pb.members[
          bareIrcCasemap(who, bareIrcCasemapping(client.state.isupport))
        ]
      }
      emit(cmd.toLowerCase(), { channel: pc, nick: who })
      return
    }
    if (cmd === 'NICK' && msg.nick) {
      var nn = msg.params[0] || ''
      if (
        bareIrcEqual(
          msg.nick,
          client.state.nick,
          bareIrcCasemapping(client.state.isupport)
        )
      ) {
        client.state.nick = nn
      }
      emit('nick', { from: msg.nick, to: nn })
      return
    }
    if (cmd === 'ERROR') {
      emit('error', { text: msg.params[0] || '' })
      return
    }
    var srv = bareIrcEnsureBuffer(client.state, 'server', '*server')
    bareIrcPushLine(client.state, srv, {
      atMs: bareIrcNow(),
      kind: 'info',
      command: cmd,
      text: (msg.params || []).join(' ')
    })
  }

  client.attach = function (socket) {
    sock = socket
    client.state.connection = 'registering'
    bareIrcEnsureBuffer(client.state, 'server', '*server')
    client.state.currentId = 'server'
    if (sock && typeof sock.on === 'function') {
      sock.on('data', function (chunk) {
        var got = lines.push(chunk)
        for (var i = 0; i < got.length; i++) {
          var parsed = bareIrcParseMessage(got[i])
          if (parsed) client.handleMessage(parsed)
        }
      })
      sock.on('error', function (err) {
        client.state.connection = 'closed'
        emit('error', { error: err })
      })
      sock.on('close', function () {
        client.state.connection = 'closed'
        emit('close', {})
      })
    }
    var nick = opts.nick || 'bareos'
    client.state.nick = nick
    client.state.requestedNick = nick
    client.sendRaw('CAP', ['LS', '302'])
    if (opts.pass) client.sendRaw('PASS', [opts.pass])
    client.sendRaw('NICK', [nick])
    client.sendRaw('USER', [
      opts.username || 'bareos',
      '0',
      '*',
      opts.realname || 'Bare OS irc'
    ])
    return client
  }

  return client
}

/** Resolve a TCP/TLS socket for /bin/irc without requiring ctx.bareOsTlsConnect. */

function bareIrcTryHostTls(ctx) {
  var req = null
  try {
    if (typeof globalThis.require === 'function') req = globalThis.require
  } catch (e) {
    req = null
  }
  if (
    !req &&
    typeof Bare !== 'undefined' &&
    Bare &&
    typeof Bare.require === 'function'
  ) {
    req = Bare.require
  }
  if (!req) return null
  var names = ['bare-tls', 'tls', 'node:tls']
  var i
  for (i = 0; i < names.length; i++) {
    try {
      var m = req(names[i])
      if (m) return m
    } catch (e2) {
      /* next */
    }
  }
  return null
}

function bareIrcTlsLib(ctx) {
  if (ctx && ctx.bare) {
    if (ctx.bare.bareTls) return ctx.bare.bareTls
    if (ctx.bare.tls) return ctx.bare.tls
  }
  return bareIrcTryHostTls(ctx)
}

function bareIrcOpenPlain(ctx, spec) {
  if (typeof ctx.bareOsTelnetConnect === 'function') {
    return ctx.bareOsTelnetConnect(spec.host, spec.port, {})
  }
  var net =
    ctx && ctx.bare && (ctx.bare.bareTcp || ctx.bare.bareNet || ctx.bare.net)
  if (net && typeof net.createConnection === 'function') {
    return net.createConnection({ host: spec.host, port: spec.port })
  }
  throw new Error('irc: no plaintext connector (ctx.bareOsTelnetConnect)')
}

function bareIrcOpenTls(ctx, spec) {
  var opts = {
    host: spec.host,
    port: spec.port,
    servername: spec.host,
    rejectUnauthorized: true
  }
  if (typeof ctx.bareOsTlsConnect === 'function') {
    return ctx.bareOsTlsConnect(spec.host, spec.port, opts)
  }
  var tls = bareIrcTlsLib(ctx)
  if (tls && typeof tls.connect === 'function') {
    return tls.connect(opts)
  }
  if (tls && typeof tls.createConnection === 'function') {
    return tls.createConnection(opts)
  }
  var Sock = tls && (tls.Socket || tls.TLSSocket)
  if (typeof Sock === 'function') {
    var tcp = bareIrcOpenPlain(ctx, spec)
    return new Sock(tcp, { host: spec.host })
  }
  throw new Error(
    'irc: no TLS connector (need ctx.bareOsTlsConnect or ctx.bare.bareTls)'
  )
}

function bareIrcDial(ctx, spec) {
  if (typeof ctx.bareOsIrcHostAllowed === 'function') {
    var gate = ctx.bareOsIrcHostAllowed(spec.host)
    if (gate && gate.ok === false) {
      throw new Error(
        'irc: host blocked (' + (gate.reason || 'policy') + '): ' + spec.host
      )
    }
  }
  if (spec.tls === false) {
    var plainOk =
      typeof ctx.bareOsIrcPlaintextAllowed === 'function'
        ? ctx.bareOsIrcPlaintextAllowed(spec.host, {
            tls: false,
            insecurePlain: spec.insecurePlain
          })
        : { ok: !bareIrcHostLooksLibera(spec.host) || spec.insecurePlain }
    if (plainOk && plainOk.ok === false) {
      throw new Error('irc: ' + (plainOk.reason || 'plaintext blocked'))
    }
    return bareIrcOpenPlain(ctx, spec)
  }
  return bareIrcOpenTls(ctx, spec)
}

/** Slash-command table for /bin/irc (modern client + common aliases). */

var BARE_IRC_FEATURED_ROOMS = [
  { name: '#libera', users: '', topic: 'Official Libera.Chat help' },
  { name: '#linux', users: '', topic: 'Linux discussion' },
  { name: '#programming', users: '', topic: 'Programming' },
  { name: '#javascript', users: '', topic: 'JavaScript' },
  { name: '#python', users: '', topic: 'Python' },
  { name: '#rust', users: '', topic: 'Rust' },
  { name: '#archlinux', users: '', topic: 'Arch Linux' },
  { name: '#debian', users: '', topic: 'Debian' },
  { name: '#ubuntu', users: '', topic: 'Ubuntu' },
  { name: '#vim', users: '', topic: 'Vim' },
  { name: '#emacs', users: '', topic: 'Emacs' },
  { name: '#git', users: '', topic: 'Git' }
]

function bareIrcNeedTarget(buf) {
  return buf && buf.kind && buf.kind !== 'server' ? buf.name : ''
}

function bareIrcModeNicks(client, chan, flag, nicks) {
  if (!chan || !nicks.length) return false
  var i
  for (i = 0; i < nicks.length; i++) {
    client.sendRaw('MODE', [chan, flag, nicks[i]])
  }
  return true
}

function bareIrcRunSlash(client, rawLine, opts) {
  opts = opts || {}
  var buf = opts.buf || null
  var ctx = opts.ctx
  var line = String(rawLine || '').trim()
  var out = {
    ok: true,
    help: false,
    rooms: false,
    roomsQuery: '',
    quit: false,
    close: false,
    clear: false,
    usage: '',
    note: ''
  }
  if (!line || line.charAt(0) !== '/') {
    out.ok = false
    return out
  }
  var body = line.slice(1)
  var sp = body.search(/\s/)
  var cmd = (sp < 0 ? body : body.slice(0, sp)).toLowerCase()
  var rest = sp < 0 ? '' : body.slice(sp + 1).trim()
  var parts = rest ? rest.split(/\s+/) : []
  var chan = bareIrcNeedTarget(buf)

  if (cmd === 'help' || cmd === 'h' || cmd === '?') {
    out.help = true
    return out
  }
  if (cmd === 'quit' || cmd === 'exit') {
    client.quit(rest || 'Leaving')
    out.quit = true
    return out
  }
  if (cmd === 'disconnect') {
    client.quit(rest || 'Disconnect')
    return out
  }
  if (cmd === 'reconnect') {
    if (opts.reconnect) opts.reconnect()
    else out.note = 'reconnect unavailable'
    return out
  }
  if (cmd === 'join' || cmd === 'j') {
    if (!parts[0]) {
      out.usage = '/join #channel [key]'
      return out
    }
    client.join(parts[0], parts[1])
    return out
  }
  if (cmd === 'part' || cmd === 'leave') {
    var pchan = parts[0] && parts[0].charAt(0) === '#' ? parts.shift() : chan
    if (!pchan) {
      out.usage = '/part [#channel] [reason]'
      return out
    }
    client.part(pchan, parts.join(' '))
    return out
  }
  if (cmd === 'cycle' || cmd === 'hop') {
    var cchan = parts[0] || chan
    if (!cchan) {
      out.usage = '/cycle [#channel]'
      return out
    }
    client.part(cchan, 'cycling')
    client.join(cchan)
    return out
  }
  if (cmd === 'query' || cmd === 'q') {
    if (!parts[0]) {
      out.usage = '/query NICK [text]'
      return out
    }
    var qb = bareIrcEnsureBuffer(client.state, 'query', parts[0])
    client.state.currentId = qb.id
    if (parts.slice(1).join(' '))
      client.sendPrivmsg(parts[0], parts.slice(1).join(' '))
    return out
  }
  if (cmd === 'msg' || cmd === 'privmsg' || cmd === 'm') {
    if (!parts[0] || !parts.slice(1).join(' ')) {
      out.usage = '/msg TARGET text'
      return out
    }
    client.sendPrivmsg(parts[0], parts.slice(1).join(' '))
    return out
  }
  if (cmd === 'notice') {
    if (!parts[0] || !parts.slice(1).join(' ')) {
      out.usage = '/notice TARGET text'
      return out
    }
    client.sendRaw('NOTICE', [parts[0], parts.slice(1).join(' ')])
    return out
  }
  if (cmd === 'nick') {
    if (!parts[0]) {
      out.usage = '/nick NEWNICK'
      return out
    }
    client.sendRaw('NICK', [parts[0]])
    return out
  }
  if (cmd === 'whois') {
    if (!parts[0]) {
      out.usage = '/whois NICK'
      return out
    }
    client.sendRaw(
      'WHOIS',
      parts.length > 1 ? [parts[0], parts[1]] : [parts[0]]
    )
    return out
  }
  if (cmd === 'whowas') {
    if (!parts[0]) {
      out.usage = '/whowas NICK'
      return out
    }
    client.sendRaw('WHOWAS', [parts[0]])
    return out
  }
  if (cmd === 'who') {
    client.sendRaw('WHO', [parts[0] || chan || '*'])
    return out
  }
  if (cmd === 'names') {
    client.sendRaw('NAMES', [parts[0] || chan || ''].filter(Boolean))
    return out
  }
  if (cmd === 'topic') {
    var tchan = chan
    var topic = rest
    if (
      parts[0] &&
      (parts[0].charAt(0) === '#' || parts[0].charAt(0) === '&')
    ) {
      tchan = parts[0]
      topic = parts.slice(1).join(' ')
    }
    if (!tchan) {
      out.usage = '/topic [#channel] [text]'
      return out
    }
    if (topic) client.sendRaw('TOPIC', [tchan, topic])
    else client.sendRaw('TOPIC', [tchan])
    return out
  }
  if (cmd === 'me' || cmd === 'action') {
    if (!rest || !chan) {
      out.usage = '/me action text  (in a channel or query)'
      return out
    }
    client.sendPrivmsg(chan, '\x01ACTION ' + rest + '\x01')
    return out
  }
  if (cmd === 'away') {
    client.sendRaw('AWAY', rest ? [rest] : [])
    return out
  }
  if (cmd === 'back') {
    client.sendRaw('AWAY', [])
    return out
  }
  if (cmd === 'quote' || cmd === 'raw') {
    if (!rest) {
      out.usage = '/quote COMMAND [params]'
      return out
    }
    var qparts = rest.split(/\s+/)
    client.sendRaw(qparts[0], qparts.slice(1))
    return out
  }
  if (cmd === 'list' || cmd === 'rooms' || cmd === 'browse') {
    out.rooms = true
    out.roomsQuery = rest
    return out
  }
  if (cmd === 'motd') {
    client.sendRaw('MOTD', parts[0] ? [parts[0]] : [])
    return out
  }
  if (cmd === 'lusers') {
    client.sendRaw('LUSERS', parts)
    return out
  }
  if (cmd === 'admin') {
    client.sendRaw('ADMIN', parts[0] ? [parts[0]] : [])
    return out
  }
  if (cmd === 'info') {
    client.sendRaw('INFO', parts[0] ? [parts[0]] : [])
    return out
  }
  if (cmd === 'time') {
    client.sendRaw('TIME', parts[0] ? [parts[0]] : [])
    return out
  }
  if (cmd === 'links') {
    client.sendRaw('LINKS', parts)
    return out
  }
  if (cmd === 'map') {
    client.sendRaw('MAP', [])
    return out
  }
  if (cmd === 'rules') {
    client.sendRaw('RULES', [])
    return out
  }
  if (cmd === 'stats') {
    client.sendRaw('STATS', parts[0] ? parts : ['u'])
    return out
  }
  if (cmd === 'version') {
    if (parts[0] && parts[0].charAt(0) !== '#') {
      client.sendRaw('PRIVMSG', [parts[0], '\x01VERSION\x01'])
      return out
    }
    client.sendRaw('VERSION', parts[0] ? [parts[0]] : [])
    return out
  }
  if (cmd === 'userhost') {
    if (!parts[0]) {
      out.usage = '/userhost NICK [NICK...]'
      return out
    }
    client.sendRaw('USERHOST', parts.slice(0, 5))
    return out
  }
  if (cmd === 'ison') {
    if (!parts[0]) {
      out.usage = '/ison NICK [NICK...]'
      return out
    }
    client.sendRaw('ISON', parts)
    return out
  }
  if (cmd === 'mode') {
    if (!parts[0]) {
      out.usage = '/mode TARGET [modes] [args]'
      return out
    }
    client.sendRaw('MODE', parts)
    return out
  }
  if (cmd === 'umode') {
    client.sendRaw(
      'MODE',
      [client.state.nick].concat(parts.length ? parts : [])
    )
    return out
  }
  if (cmd === 'kick') {
    var kchan = chan
    var knick = parts[0]
    var kreason = parts.slice(1).join(' ')
    if (
      parts[0] &&
      (parts[0].charAt(0) === '#' || parts[0].charAt(0) === '&')
    ) {
      kchan = parts[0]
      knick = parts[1]
      kreason = parts.slice(2).join(' ')
    }
    if (!kchan || !knick) {
      out.usage = '/kick [channel] NICK [reason]'
      return out
    }
    client.sendRaw('KICK', kreason ? [kchan, knick, kreason] : [kchan, knick])
    return out
  }
  if (cmd === 'invite') {
    if (!parts[0]) {
      out.usage = '/invite NICK [#channel]'
      return out
    }
    var ichan = parts[1] || chan
    if (!ichan) {
      out.usage = '/invite NICK #channel'
      return out
    }
    client.sendRaw('INVITE', [parts[0], ichan])
    return out
  }
  if (cmd === 'ban') {
    if (!chan) {
      out.usage = '/ban [mask]  (in a channel)'
      return out
    }
    if (!parts[0]) client.sendRaw('MODE', [chan, '+b'])
    else client.sendRaw('MODE', [chan, '+b', parts[0]])
    return out
  }
  if (cmd === 'unban') {
    if (!chan || !parts[0]) {
      out.usage = '/unban mask  (in a channel)'
      return out
    }
    client.sendRaw('MODE', [chan, '-b', parts[0]])
    return out
  }
  if (cmd === 'op') {
    if (!chan || !parts[0]) {
      out.usage = '/op NICK [NICK...]  (in a channel)'
      return out
    }
    bareIrcModeNicks(client, chan, '+o', parts)
    return out
  }
  if (cmd === 'deop') {
    if (!chan || !parts[0]) {
      out.usage = '/deop NICK [NICK...]'
      return out
    }
    bareIrcModeNicks(client, chan, '-o', parts)
    return out
  }
  if (cmd === 'voice') {
    if (!chan || !parts[0]) {
      out.usage = '/voice NICK [NICK...]'
      return out
    }
    bareIrcModeNicks(client, chan, '+v', parts)
    return out
  }
  if (cmd === 'devoice') {
    if (!chan || !parts[0]) {
      out.usage = '/devoice NICK [NICK...]'
      return out
    }
    bareIrcModeNicks(client, chan, '-v', parts)
    return out
  }
  if (cmd === 'knock') {
    if (!parts[0]) {
      out.usage = '/knock #channel [message]'
      return out
    }
    client.sendRaw(
      'KNOCK',
      parts.slice(1).join(' ')
        ? [parts[0], parts.slice(1).join(' ')]
        : [parts[0]]
    )
    return out
  }
  if (cmd === 'ctcp') {
    if (!parts[0] || !parts[1]) {
      out.usage = '/ctcp NICK CMD [args]'
      return out
    }
    var ctcp =
      parts[1].toUpperCase() +
      (parts.slice(2).join(' ') ? ' ' + parts.slice(2).join(' ') : '')
    client.sendRaw('PRIVMSG', [parts[0], '\x01' + ctcp + '\x01'])
    return out
  }
  if (cmd === 'ping') {
    if (parts[0]) {
      client.sendRaw('PRIVMSG', [parts[0], '\x01PING ' + Date.now() + '\x01'])
    } else {
      client.sendRaw('PING', [client.state.nick || 'irc'])
    }
    return out
  }
  if (cmd === 'ignore') {
    if (!parts[0]) {
      var keys = Object.keys(client.state.ignore || {})
      out.note = keys.length
        ? 'ignoring: ' + keys.join(', ')
        : 'ignore list empty'
      return out
    }
    if (!client.state.ignore) client.state.ignore = {}
    client.state.ignore[
      bareIrcCasemap(parts[0], bareIrcCasemapping(client.state.isupport))
    ] = parts[0]
    out.note = 'ignoring ' + parts[0]
    return out
  }
  if (cmd === 'unignore') {
    if (!parts[0]) {
      out.usage = '/unignore NICK'
      return out
    }
    if (client.state.ignore) {
      delete client.state.ignore[
        bareIrcCasemap(parts[0], bareIrcCasemapping(client.state.isupport))
      ]
    }
    out.note = 'unignored ' + parts[0]
    return out
  }
  if (cmd === 'clear') {
    out.clear = true
    return out
  }
  if (cmd === 'close' || cmd === 'wc') {
    out.close = true
    return out
  }
  if (cmd === 'win' || cmd === 'buffer' || cmd === 'window') {
    var n = parseInt(parts[0], 10)
    var list = bareIrcListBuffers(client.state)
    if (n >= 1 && n <= list.length) client.state.currentId = list[n - 1].id
    else out.usage = '/win N   (1–' + list.length + ')'
    return out
  }
  if (cmd === 'p2p') {
    if (parts[0] === 'open' && parts[1]) {
      var name = String(parts[1])
      if (name.indexOf('[p2p]') < 0) name = name + ' [p2p]'
      var pb = bareIrcEnsureBuffer(client.state, 'p2p', name)
      client.state.currentId = pb.id
      bareIrcPushLine(client.state, pb, {
        atMs: Date.now(),
        kind: 'info',
        text: 'Shadow room — not Libera. Messages stay on the swarm sideband.'
      })
      if (ctx && typeof ctx.bareOsIrcShadowOpen === 'function') {
        try {
          ctx.bareOsIrcShadowOpen(parts[1])
        } catch (e) {
          /* ignore */
        }
      }
      return out
    }
    out.usage = '/p2p open #name'
    return out
  }
  if (cmd === 'oper') {
    if (parts.length < 2) {
      out.usage = '/oper USER PASS'
      return out
    }
    client.sendRaw('OPER', [parts[0], parts[1]])
    return out
  }
  if (cmd === 'squery') {
    if (!parts[0] || !parts.slice(1).join(' ')) {
      out.usage = '/squery SERVICE text'
      return out
    }
    client.sendRaw('SQUERY', [parts[0], parts.slice(1).join(' ')])
    return out
  }
  if (cmd === 'set') {
    out.note = 'config is ~/.irc/config.json (nick, autojoin, saslUser)'
    return out
  }
  if (cmd === 'server') {
    out.note =
      (client.state.network || 'irc') +
      ' ' +
      (client.opts.host || '') +
      ':' +
      (client.opts.port || '')
    return out
  }

  out.ok = false
  out.usage = 'unknown command /' + cmd + '   try /help'
  return out
}

/** TEA IRC TUI. Cell buffer; protocol lives in irc-client.js. */

function bareIrcPad(s, w) {
  s = String(s == null ? '' : s)
  if (w <= 0) return ''
  if (s.length > w) return s.slice(0, w)
  while (s.length < w) s += ' '
  return s
}

function bareIrcNickColWidth(cols, buf, roomsOpen) {
  if (roomsOpen || !buf || buf.kind !== 'channel') return 0
  if (cols < 80) return 0
  return cols >= 140 ? 20 : 16
}

function bareIrcMemberLabel(m, key) {
  var pref =
    m && m.modes && m.modes.indexOf('o') >= 0
      ? '@'
      : m && m.modes && m.modes.indexOf('v') >= 0
        ? '+'
        : ' '
  return pref + (m && m.nick ? m.nick : key)
}

function bareIrcFmtClock(ms) {
  var d = new Date(typeof ms === 'number' ? ms : Date.now())
  function z(n) {
    return (n < 10 ? '0' : '') + n
  }
  return z(d.getHours()) + ':' + z(d.getMinutes())
}

function bareIrcCreateTuiApp(ctx, client) {
  var tui = ctx.tui
  var size0 = tui && typeof tui.size === 'function' ? tui.size() : {}
  return {
    client: client,
    width: size0.width || 80,
    height: size0.height || 24,
    help: false,
    quitConfirm: false,
    roomsOpen: false,
    roomsCursor: 0,
    roomsFilterEdit: false,
    openedRoomsOnce: false,
    filterOpen: false,
    status: 'connecting…',
    input: tui.textinput.create({ prompt: '', focused: true, charLimit: 450 }),
    viewport: tui.viewport.create({
      width: size0.width || 80,
      height: Math.max(6, (size0.height || 24) - 6)
    }),
    init: function () {
      var self = this
      client.on('registered', function () {
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('privmsg', function () {
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('notice', function () {
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('sasl', function (p) {
        self.status = p && p.ok ? 'sasl ok' : 'sasl failed'
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('error', function (p) {
        self.status =
          'error: ' +
          ((p && (p.text || (p.error && p.error.message))) || 'error')
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('close', function () {
        self.status = 'disconnected'
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('join', function () {
        self.roomsOpen = false
        self.roomsFilterEdit = false
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('list', function () {
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('listend', function (p) {
        self.status = 'rooms ' + ((p && p.count) || 0)
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      client.on('motd_end', function () {
        var joins = (client.opts && client.opts.autojoin) || []
        if (!self.openedRoomsOnce && (!joins || !joins.length)) {
          self.openedRoomsOnce = true
          self.roomsOpen = true
          self.roomsCursor = 0
          self.status = 'pick a room  (Enter join  / filter  Esc close)'
        }
        var srv = bareIrcEnsureBuffer(client.state, 'server', '*server')
        bareIrcPushLine(client.state, srv, {
          atMs: Date.now(),
          kind: 'info',
          text:
            'You are ' +
            (client.state.nick || 'guest') +
            '.  /rooms browse   /join #libera help   /query nick   ? keys'
        })
        if (tui && typeof tui.send === 'function')
          tui.send({ type: 'irc.paint' })
      })
      this._sync()
      return null
    },
    _roomRows: function () {
      var listed = this.client.state.channelList || []
      if (listed.length) return listed
      return BARE_IRC_FEATURED_ROOMS
    },
    _openRooms: function (query) {
      this.roomsOpen = true
      this.roomsCursor = 0
      this.roomsFilterEdit = false
      if (query) this.client.list(query)
      this.status = query
        ? 'listing ' + query
        : 'featured rooms  (type /rooms linux to search)'
    },
    _joinRoomAtCursor: function () {
      var rows = this._roomRows()
      var hit = rows[this.roomsCursor]
      if (!hit || !hit.name) return
      this.roomsOpen = false
      this.roomsFilterEdit = false
      this.client.join(hit.name)
      this.status = 'joining ' + hit.name
    },
    _current: function () {
      var st = this.client.state
      return (
        st.buffers[st.currentId] || bareIrcEnsureBuffer(st, 'server', '*server')
      )
    },
    _sync: function () {
      var buf = this._current()
      buf.unread = 0
      buf.highlight = false
      var cols = Math.max(40, this.width || 80)
      var nickW = bareIrcNickColWidth(cols, buf, this.roomsOpen)
      this.viewport.width = Math.max(20, cols - (nickW ? nickW + 1 : 0))
      this.viewport.height = Math.max(4, (this.height || 24) - 6)
      if (this.roomsOpen) {
        var rows = this._roomRows()
        if (this.roomsCursor >= rows.length)
          this.roomsCursor = Math.max(0, rows.length - 1)
        var rlines = []
        var ri
        for (ri = 0; ri < rows.length; ri++) {
          var rr = rows[ri]
          var mark = ri === this.roomsCursor ? '>' : ' '
          var users =
            rr.users === '' || rr.users == null
              ? '    '
              : String(rr.users).padStart
                ? String(rr.users).padStart(4, ' ')
                : String(rr.users)
          rlines.push(
            mark +
              ' ' +
              String(rr.name || '')
                .slice(0, 18)
                .padEnd(18, ' ') +
              ' ' +
              users +
              '  ' +
              String(rr.topic || '')
          )
        }
        if (!rlines.length) rlines.push('(no rooms — /rooms linux to search)')
        this.viewport.setContent(rlines.join('\n'))
        var mid = Math.floor((this.viewport.height || 8) / 2)
        this.viewport.setYOffset(Math.max(0, this.roomsCursor - mid))
        return
      }
      var lines = []
      for (var i = 0; i < buf.lines.length; i++) {
        var rec = buf.lines[i]
        var clock = bareIrcFmtClock(rec.atMs)
        if (rec.kind === 'action') {
          lines.push(clock + ' * ' + rec.from + ' ' + rec.text)
        } else if (rec.kind === 'notice') {
          lines.push(clock + ' -' + rec.from + '- ' + rec.text)
        } else if (rec.kind === 'privmsg') {
          lines.push(clock + ' <' + rec.from + '> ' + rec.text)
        } else {
          lines.push(clock + ' ' + (rec.text || rec.command || ''))
        }
      }
      this.viewport.setContent(lines.join('\n'))
      this.viewport.gotoBottom()
    },
    _nextBuffer: function (dir) {
      var list = bareIrcListBuffers(this.client.state)
      if (!list.length) return
      var cur = 0
      for (var i = 0; i < list.length; i++) {
        if (list[i].id === this.client.state.currentId) cur = i
      }
      var n = (cur + dir + list.length) % list.length
      this.client.state.currentId = list[n].id
      this._sync()
    },
    _completeNick: function () {
      var buf = this._current()
      var val = this.input.value || ''
      var m = /(?:^|\s)(\S+)$/.exec(val)
      var prefix = m ? m[1] : ''
      if (!prefix) return
      var mapping = bareIrcCasemapping(this.client.state.isupport)
      var keys = Object.keys(buf.members || {})
      var hit = ''
      for (var i = 0; i < keys.length; i++) {
        var mem = buf.members[keys[i]]
        var nick = mem && mem.nick ? mem.nick : keys[i]
        if (
          bareIrcCasemap(nick, mapping).indexOf(
            bareIrcCasemap(prefix, mapping)
          ) === 0
        ) {
          hit = nick
          break
        }
      }
      if (!hit) return
      this.input.setValue(val.slice(0, val.length - prefix.length) + hit)
    },
    _applySlash: function (res) {
      var buf = this._current()
      if (res.help) this.help = true
      if (res.rooms) this._openRooms(res.roomsQuery || '')
      if (res.note) {
        bareIrcPushLine(this.client.state, buf, {
          atMs: Date.now(),
          kind: 'info',
          text: res.note
        })
      }
      if (res.usage) {
        bareIrcPushLine(this.client.state, buf, {
          atMs: Date.now(),
          kind: 'info',
          text: res.usage
        })
      }
      if (res.clear && buf) buf.lines = []
      if (res.close) {
        if (buf.kind === 'channel') this.client.part(buf.name, '')
        var id = buf.id
        if (id !== 'server') {
          delete this.client.state.buffers[id]
          this.client.state.currentId = 'server'
        }
      }
      if (res.quit) return tui.quit
      this._sync()
      return null
    },
    _runSlash: function (line) {
      var self = this
      var res = bareIrcRunSlash(this.client, line, {
        buf: this._current(),
        ctx: ctx,
        reconnect: function () {
          try {
            if (self.client.opts) {
              self.client.attach(bareIrcDial(ctx, self.client.opts))
              self.status = 'reconnecting\u2026'
            }
          } catch (err) {
            self.status = 'reconnect failed'
          }
        }
      })
      return this._applySlash(res)
    },
    update: function (msg) {
      if (msg && msg.type === 'resize') {
        this.width = msg.width || this.width
        this.height = msg.height || this.height
        this._sync()
        return [this, null]
      }
      if (msg && msg.type === 'irc.paint') {
        this.status = this.client.state.registered
          ? this.client.state.saslOk
            ? 'sasl ok'
            : 'registered'
          : this.client.state.connection
        this._sync()
        return [this, null]
      }
      if (this.help) {
        if (msg && msg.type === 'key') this.help = false
        return [this, null]
      }
      if (this.roomsOpen) {
        if (this.roomsFilterEdit) {
          if (tui.key.matches(msg, 'escape')) {
            this.roomsFilterEdit = false
            this.input.reset()
            return [this, null]
          }
          if (tui.key.matches(msg, 'enter')) {
            var q = String(this.input.value || '').trim()
            this.input.reset()
            this.roomsFilterEdit = false
            if (q) this.client.list(q)
            this.status = q ? 'listing ' + q : 'rooms'
            this._sync()
            return [this, null]
          }
          var rpair = this.input.update(msg)
          this.input = rpair[0]
          return [this, rpair[1]]
        }
        if (tui.key.matches(msg, 'escape', 'q')) {
          this.roomsOpen = false
          this._sync()
          return [this, null]
        }
        if (tui.key.matches(msg, '/', 'f')) {
          this.roomsFilterEdit = true
          this.input.reset()
          return [this, null]
        }
        if (tui.key.matches(msg, 'enter')) {
          this._joinRoomAtCursor()
          this._sync()
          return [this, null]
        }
        if (tui.key.matches(msg, 'j', 'down')) {
          this.roomsCursor++
          this._sync()
          return [this, null]
        }
        if (tui.key.matches(msg, 'k', 'up')) {
          this.roomsCursor = Math.max(0, this.roomsCursor - 1)
          this._sync()
          return [this, null]
        }
        if (tui.key.matches(msg, 'pageup', 'pagedown')) {
          var step = this.viewport.height || 10
          if (tui.key.matches(msg, 'pageup'))
            this.roomsCursor = Math.max(0, this.roomsCursor - step)
          else this.roomsCursor += step
          this._sync()
          return [this, null]
        }
      }
      if (this.quitConfirm) {
        if (tui.key.matches(msg, 'y', 'Y')) {
          this.client.quit('Quit')
          return [this, tui.quit]
        }
        if (msg && msg.type === 'key') this.quitConfirm = false
        return [this, null]
      }
      if (tui.key.matches(msg, 'ctrl+c')) {
        this.quitConfirm = true
        return [this, null]
      }
      if (tui.key.matches(msg, 'f10')) {
        this.client.quit('Quit')
        return [this, tui.quit]
      }
      if (tui.key.matches(msg, '?')) {
        this.help = true
        return [this, null]
      }
      if (tui.key.matches(msg, 'ctrl+l')) {
        this._openRooms('')
        this._sync()
        return [this, null]
      }
      if (tui.key.matches(msg, 'ctrl+n', 'alt+right')) {
        this._nextBuffer(1)
        return [this, null]
      }
      if (tui.key.matches(msg, 'ctrl+p', 'alt+left')) {
        this._nextBuffer(-1)
        return [this, null]
      }
      if (tui.key.matches(msg, 'tab')) {
        this._completeNick()
        return [this, null]
      }
      if (tui.key.matches(msg, 'pageup', 'pagedown', 'up', 'down')) {
        var vp = this.viewport.update(msg)
        this.viewport = vp[0]
        return [this, vp[1]]
      }
      if (tui.key.matches(msg, 'enter')) {
        var line = String(this.input.value || '').trim()
        this.input.reset()
        if (!line) return [this, null]
        if (line.charAt(0) === '/') {
          var cmd = this._runSlash(line)
          return [this, cmd]
        }
        var cur = this._current()
        if (cur.kind === 'server') {
          bareIrcPushLine(this.client.state, cur, {
            atMs: Date.now(),
            kind: 'info',
            text: 'join a channel or /query someone first'
          })
        } else if (cur.kind === 'p2p') {
          bareIrcPushLine(this.client.state, cur, {
            atMs: Date.now(),
            kind: 'privmsg',
            from: this.client.state.nick || 'me',
            text: line,
            local: true
          })
          if (typeof ctx.bareOsChatSend === 'function') {
            try {
              ctx.bareOsChatSend(
                '[bare-os-irc-shadow] ' + cur.name + ' ' + line
              )
            } catch (e) {
              /* ignore */
            }
          }
        } else {
          this.client.sendPrivmsg(cur.name, line)
        }
        this._sync()
        return [this, null]
      }
      var pair = this.input.update(msg)
      this.input = pair[0]
      return [this, pair[1]]
    },
    view: function () {
      var cols = Math.max(40, this.width || 80)
      var rows = Math.max(12, this.height || 24)
      var st = tui.style
      var buf = this._current()
      var net = this.client.state.network || 'irc'
      var tls = this.client.state.tls ? 'tls' : 'plain'
      var titleRaw =
        ' ' +
        net +
        '  ' +
        buf.name +
        (buf.unread ? ' ● ' + buf.unread : '') +
        '  ' +
        tls +
        (this.client.state.saslOk ? '  sasl' : '') +
        '  ' +
        this.status +
        '  ' +
        cols +
        'x' +
        rows +
        ' '
      var title = st
        ? st()
            .foreground('brightwhite')
            .background('blue')
            .width(cols)
            .render(titleRaw)
        : titleRaw
      var tabs = bareIrcListBuffers(this.client.state)
        .map(function (b) {
          var mark = b.id === buf.id ? '[' + b.name + ']' : b.name
          if (b.unread) mark += '(' + b.unread + ')'
          return mark
        })
        .join('  ')
      var tabBar = st ? st().dim().width(cols).render(tabs) : tabs
      var nickW = bareIrcNickColWidth(cols, buf, this.roomsOpen)
      var bodyH = this.viewport.height || Math.max(4, rows - 6)
      var body = this.viewport.view()
      if (nickW && buf.kind === 'channel') {
        var keys = Object.keys(buf.members || {})
        keys.sort(function (a, b) {
          var ma = buf.members[a]
          var mb = buf.members[b]
          var pa = ma && ma.modes && ma.modes.indexOf('o') >= 0 ? 0 : 1
          var pb = mb && mb.modes && mb.modes.indexOf('o') >= 0 ? 0 : 1
          if (pa !== pb) return pa - pb
          var na = ma && ma.nick ? ma.nick : a
          var nb = mb && mb.nick ? mb.nick : b
          return na < nb ? -1 : na > nb ? 1 : 0
        })
        var nicks = keys.map(function (k) {
          return bareIrcMemberLabel(buf.members[k], k)
        })
        var left = String(body).split('\n')
        var chatW = Math.max(8, cols - nickW - 1)
        var joined = []
        var r
        for (r = 0; r < bodyH; r++) {
          var L = bareIrcPad(
            st ? st.truncate(left[r] || '', chatW) : left[r] || '',
            chatW
          )
          var R = bareIrcPad(nicks[r] || '', nickW)
          joined.push(L + '\u2502' + R)
        }
        body = joined.join('\n')
      }
      var prompt
      if (this.roomsOpen && this.roomsFilterEdit) {
        prompt =
          'Filter: ' +
          (this.input.view ? this.input.view() : this.input.value || '')
      } else {
        prompt =
          (buf.kind === 'p2p' ? '#p2p ' : '') +
          '[' +
          (this.roomsOpen ? 'rooms' : buf.name) +
          '] ' +
          (this.input.view ? this.input.view() : this.input.value || '')
      }
      var footRaw = this.roomsOpen
        ? this.roomsFilterEdit
          ? 'Filter + Enter search LIST   Esc back'
          : 'Enter join  j/k move  / filter  Esc close  featured or /rooms linux'
        : 'Enter send  /rooms  /join  /query  Ctrl+L rooms  Ctrl+n/p  Tab nick  ?'
      var foot = st ? st().dim().width(cols).render(footRaw) : footRaw
      var rule = st
        ? st()
            .dim()
            .width(cols)
            .render('\u2500'.repeat(Math.min(cols, 120)))
        : ''
      var lines = [title, tabBar, rule]
        .concat(String(body).split('\n'))
        .concat([rule, prompt, foot])
      while (lines.length < rows) lines.push('')
      var out = []
      for (var i = 0; i < rows; i++) {
        out.push(
          st
            ? st.truncate(lines[i] || '', cols)
            : String(lines[i] || '').slice(0, cols)
        )
      }
      return out.join('\n')
    },
    overlay: function (size) {
      if (!this.help && !this.quitConfirm) return null
      var cols = (size && size.width) || this.width || 80
      var rows = (size && size.height) || this.height || 24
      var st = tui.style
      var body = this.quitConfirm
        ? 'Disconnect and quit?\n\nY yes   any other key cancel'
        : 'Bare OS irc\n\n' +
          '/rooms [pat]  browse/list   /join #chan   /part  /query nick\n' +
          '/msg /notice /me /nick /whois /whowas /who /names /topic\n' +
          '/kick /invite /op /deop /voice /mode /ban /away /back\n' +
          '/list /motd /quote /ctcp /ping /ignore /clear /close /quit\n' +
          '/p2p open #chan   shadow room (not Libera)\n' +
          'Ctrl+L rooms   Ctrl+n/p buffers   Tab nick\n\n' +
          'Default: irc.libera.chat:6697 TLS   random nick if unset\n' +
          'Press any key to close.'
      var boxed = st
        ? st()
            .border(st.borders.rounded)
            .padding(1, 2)
            .background('black')
            .render(body)
        : body
      var h = st ? st.height(boxed) : boxed.split('\n').length
      var w = st ? st.width(boxed) : 48
      return {
        row: Math.max(0, Math.floor((rows - h) / 2)),
        col: Math.max(0, Math.floor((cols - w) / 2)),
        text: boxed
      }
    }
  }
}

function bareIrcTuiRunOpts() {
  return { buffer: 'cell' }
}

/**
 * Modern IRC client. Default: Libera.Chat TLS irc.libera.chat:6697.
 * TTY → ctx.tui; otherwise scriptable: status | send | join | query | whois.
 */
function ircUsage(argv0) {
  return (
    'usage: ' +
    (argv0 || 'irc') +
    ' [libera|HOST] [--tls|--plain] [--insecure-plain] [--nick N] [--sasl-user U]\n' +
    '       ' +
    (argv0 || 'irc') +
    ' send TARGET TEXT | join #chan | query NICK [TEXT] | whois NICK | status\n' +
    'Default network: irc.libera.chat:6697 (TLS). Config: ~/.irc/config.json\n' +
    'See man irc.'
  )
}

async function bareIrcEnsureLiveClient(ctx, spec) {
  if (
    ctx._bareIrcClient &&
    ctx._bareIrcClient.state.connection === 'registered'
  ) {
    return ctx._bareIrcClient
  }
  var sock = bareIrcDial(ctx, spec)
  var client = bareIrcCreateClient(spec)
  client.attach(sock)
  ctx._bareIrcClient = client
  return client
}

function bareIrcWaitRegistered(client, ms) {
  return new Promise(function (resolve, reject) {
    if (client.state.registered) {
      resolve(client)
      return
    }
    var t = setTimeout(function () {
      reject(new Error('irc: register timeout'))
    }, ms || 20000)
    client.on('registered', function () {
      clearTimeout(t)
      resolve(client)
    })
    client.on('error', function (p) {
      clearTimeout(t)
      reject(
        p && p.error ? p.error : new Error(p && p.text ? p.text : 'irc error')
      )
    })
  })
}

async function run(ctx, argv) {
  var flags = bareIrcParseFlags(argv)
  if (flags.help) {
    ctx.console.log(ircUsage(argv[0]))
    return
  }

  var loaded = await bareIrcLoadConfig(ctx)
  var spec = bareIrcResolveConnect(ctx, flags, loaded)
  var sub = flags.rest[0] || ''

  if (sub === 'status') {
    var c = ctx._bareIrcClient
    var info = {
      connection: c ? c.state.connection : 'idle',
      nick: c ? c.state.nick : spec.nick,
      host: spec.host,
      port: spec.port,
      tls: spec.tls,
      network: spec.network
    }
    ctx.console.log(
      flags.json ? JSON.stringify(info) : JSON.stringify(info, null, 2)
    )
    return
  }

  if (sub === 'send' || sub === 'join' || sub === 'query' || sub === 'whois') {
    try {
      var client = await bareIrcEnsureLiveClient(ctx, spec)
      await bareIrcWaitRegistered(client, 25000)
      if (sub === 'send') {
        var target = flags.rest[1]
        var text = flags.rest.slice(2).join(' ')
        if (!target || !text) {
          ctx.console.error('irc: send TARGET TEXT')
          ctx.exitCode = 1
          return
        }
        if (!client.sendPrivmsg(target, text)) {
          ctx.console.error('irc: send failed (rate limit or no socket)')
          ctx.exitCode = 1
        }
        return
      }
      if (sub === 'join') {
        if (!flags.rest[1]) {
          ctx.console.error('irc: join #channel')
          ctx.exitCode = 1
          return
        }
        client.join(flags.rest[1])
        return
      }
      if (sub === 'query') {
        if (!flags.rest[1]) {
          ctx.console.error('irc: query NICK [TEXT]')
          ctx.exitCode = 1
          return
        }
        if (flags.rest[2])
          client.sendPrivmsg(flags.rest[1], flags.rest.slice(2).join(' '))
        return
      }
      if (sub === 'whois') {
        if (!flags.rest[1]) {
          ctx.console.error('irc: whois NICK')
          ctx.exitCode = 1
          return
        }
        client.sendRaw('WHOIS', [flags.rest[1]])
        return
      }
    } catch (e) {
      ctx.console.error('irc: ' + ((e && e.message) || String(e)))
      ctx.exitCode = 1
    }
    return
  }

  var stdin = ctx.replStdin
  var isTTY = Boolean(stdin && stdin.isTTY)
  if (!isTTY || !ctx.tui || typeof ctx.tui.run !== 'function') {
    ctx.console.error(
      'irc: TTY + ctx.tui required for full-screen mode; use: irc send TARGET TEXT'
    )
    ctx.exitCode = 1
    return
  }

  try {
    if (typeof ctx.bareOsIrcHostAllowed === 'function') {
      var allow = ctx.bareOsIrcHostAllowed(spec.host)
      if (allow && allow.ok === false) {
        ctx.console.error(
          'irc: host blocked (' + (allow.reason || 'policy') + '): ' + spec.host
        )
        ctx.exitCode = 1
        return
      }
    }
    var socket = bareIrcDial(ctx, spec)
    var live = bareIrcCreateClient(spec)
    live.attach(socket)
    live.on('registered', function () {
      if (spec.generatedNick && live.state.nick) {
        bareIrcRememberNick(ctx, live.state.nick)
      }
      var joins = spec.autojoin || []
      for (var i = 0; i < joins.length; i++) live.join(joins[i])
      if (typeof ctx.bareOsIrcPresencePublish === 'function') {
        try {
          ctx.bareOsIrcPresencePublish({
            schema: 1,
            network: spec.network || 'libera',
            nick: live.state.nick,
            account: live.state.account || '',
            channels: spec.shareChannels ? joins : [],
            atMs: Date.now()
          })
        } catch (e) {
          /* ignore */
        }
      }
    })
    var app = bareIrcCreateTuiApp(ctx, live)
    try {
      await ctx.tui.run(app, bareIrcTuiRunOpts())
    } finally {
      try {
        live.quit('Client closed')
      } catch (e2) {
        /* ignore */
      }
    }
  } catch (err) {
    ctx.console.error('irc: ' + ((err && err.message) || String(err)))
    ctx.exitCode = 1
  }
}