#compdef dos2unix unix2dos mac2unix unix2mac

local variant ret=1
local -a context expl line state state_descr cp_opts xl_opts args
local -A opt_args

# Code-page options for ISO translation (use group `cp`)
cp_opts=(
  '(-7 -ascii)-437[use DOS code page 437 (US) for ISO translation]'
  '(-7 -ascii)-850[use DOS code page 850 (Western European) for ISO translation]'
  '(-7 -ascii)-860[use DOS code page 860 (Portuguese) for ISO translation]'
  '(-7 -ascii)-863[use DOS code page 863 (French Canadian) for ISO translation]'
  '(-7 -ascii)-865[use DOS code page 865 (Nordic) for ISO translation]'

  '(-7 -ascii)-1252[use Windows code page 1252 (Western European) for ISO translation]'
)
# Translation/conversion options (use group `xl`)
xl_opts=(
  '(cp)-7[also replace 8-bit characters by 7-bit spaces]'
  '(cp)-ascii[convert only line breaks (CRLF<->LF)]'
  '-iso[also convert between DOS and ISO character sets]'

  {-c,--convmode}'[specify conversion mode]:conversion mode:((
    7bit\:"also replace 8-bit characters by 7-bit spaces"
    ascii\:"convert only line breaks (CRLF<->LF)"
    iso\:"also convert between DOS and ISO character sets"
    mac\:"convert only line breaks (CR<->LF)"
  ))'
  {-ub,--assume-utf16be}'[assume input file format is UTF-16BE]'
  {-ul,--assume-utf16le}'[assume input file format is UTF-16LE]'
)

# `dos2unix` here is the dos2unix package provided by many Linux distributions,
# Homebrew, &al. `unix2dos` is the unix2dos package provided by FreeBSD, &al.
# Some implementations (Solaris) don't bother with any kind of argument
# validation, so we pass in /dev/null to make sure they never hang
_pick_variant -r variant \
  dos2unix='(#i)waterlan' \
  unix2dos='-p' \
  $OSTYPE \
  --version /dev/null{,}

case $variant in
  dos2unix)
    # -D and -gb are omitted, since they only make sense on Windows
    args=(
      '(: * -)'{-h,--help}'[display help information]'
      '(: * -)'{-L,--license}'[display license information]'
      '(: * -)'{-V,--version}'[display version information]'
      '(-l --newline)'{-l,--newline}'[write two line breaks to output for each converted line break]'
      '(-u --keep-utf16)'{-u,--keep-utf16}'[write output in same UTF-16 encoding as input]'
      '*:: :->file'
      + '(qv)' # Verbosity options
      {-q,--quiet}'[reduce output verbosity]'
      {-v,--verbose}'[increase output verbosity]'
      + '(cp)' # Code-page options
      $cp_opts
      + '(xl)' # Translation/conversion options
      $xl_opts
      + bm # BOM options
      '(-b -r --keep-bom --remove-bom)'{-b,--keep-bom}'[write existing BOM to output]'
      '(-m -r --add-bom --remove-bom)'{-m,--add-bom}'[write new BOM to output]'
      '(bm)'{-r,--remove-bom}"[don't write BOM to output]"
      + '(ch)' # chown options
      '--allow-chown[allow file-ownership changes in old-file mode]'
      "--no-allow-chown[don't allow file-ownership changes in old-file mode]"
      + '(fs)' # Force/safe options
      {-f,--force}'[force conversion of binary files]'
      {-s,--safe}'[skip binary files]'
      + '(in)' # Info options
      {-i-,--info=-}'[display (specified) file information]:: :->info'
      + '(ln)' # Symlink options
      {-F,--follow-symlink}'[follow symbolic links]'
      {-R,--replace-symlink}'[replace symbolic links]'
      {-S,--skip-symlink}'[skip symbolic links]'
      + '(no)' # File-mode options
      {-n,--newfile}'[convert each input file to specified output file]'
      {-o,--oldfile}'[convert input files in place]'
    )
    # No stacking!
    _arguments -S -A '-*' : $args && ret=0

    case $state in
      file)
        if (( CURRENT % 2 == 0 )) && [[ -n ${opt_args[(I)*-(-n|--newfile)]} ]]; then
          _description files expl 'output file'
        else
          _description files expl 'input file'
        fi
        _files "${(@)expl}" && ret=0
        ;;
      info)
        _values -s '' 'information flag [dumbt]' \
          '0[end each output line with NUL instead of newline]' \
          'b[show BOM type]' \
          'c[show only files that would be converted]' \
          'd[show number of DOS line breaks (CRLF)]' \
          'h[show header]' \
          'm[show number of Mac line breaks (CR)]' \
          'p[show file names without paths]' \
          't[show whether file is text or binary]' \
          'u[show number of UNIX line breaks (LF)]' \
        && ret=0
        ;;
    esac

    return ret
    ;;
  unix2dos)
    _arguments -s -S -A '-*' : \
      '-p[preserve access and modification times]' \
      '*:input file:_files'
    return
    ;;
  solaris*)
    _arguments -A '-*' : \
      '1:input file:_files' \
      '2:output file:_files' \
      + '(cp)' \
      ${(@M)cp_opts:#(|\([^\)]#\))-(437|850|860|863|865)(|\[*)} \
      + '(xl)' \
      ${(@M)xl_opts:#(|\([^\)]#\))-(7|ascii|iso)(|\[*)}
    return
    ;;
  *)
    _default
    return
    ;;
esac