#compdef du

if _pick_variant gnu=Free\ Soft unix --version /dummy/no-such-file; then
  local ret=1

  _arguments -s \
    '(-a --all -s --summarize)'{-a,--all}'[write counts for all files]' \
    '--apparent-size[print apparent sizes rather than disc usage]' \
    '(-B --block-size -k)'{-B,--block-size=}'[specify block size]:size (bytes)' \
    '(-B --block-size -k --apparent-size -b --bytes)'{-b,--bytes}'[equivalent to --apparent-size --block-size=1]' \
    '(-c --total)'{-c,--total}'[produce a grand total]' \
    '(-H -D --dereference-args -L --dereference -P --no-dereference)'{-H,-D,--dereference-args}'[dereference arguments that are symlinks]' \
    '(-H -D --dereference-args -L --dereference -P --no-dereference)'{-P,--no-dereference}'[do not dereference any symlinks]' \
    '(-h --human-readable -H --si)'{-h,--human-readable}'[print sizes in human readable format]' \
    '(--si -h --human-readable)--si[human readable form using powers of 1000]' \
    '(-B --block-size)-k[use block size of 1k]' \
    '(-B --block-size)-m[use block size of 1M]' \
    '(-l --count-links)'{-l,--count-links}'[count sizes many times if hard linked]' \
    '(-L --dereference -H -D --dereference-args -P --no-dereference)'{-L,--dereference}'[dereference all symlinks]' \
    '(-S --separate-dirs)'{-S,--separate-dirs}'[do not include size of subdirectories]' \
    '(-s --summarize --max-depth -a --all)'{-s,--summarize}'[only display total for each argument]' \
    '(-x --one-file-system)'{-x,--one-file-system}'[skip directories on different filesystems]' \
    '(-0 --null)'{-0,--null}'[end each output line with NUL instead of newline]' \
    \*{-X+,--exclude-from=}'[exclude files matching any pattern in file]:file:_files' \
    '*--exclude=[exclude files matching pattern]:pattern' \
    '(-s --summarize)--max-depth=[maximum levels to recurse]:levels' \
    '--files0-from=[use NUL-terminated list of files from file]:file' \
    '--time-style=[show times using given style, +FORMAT for strftime formatted args]:style:->timestyle' \
    '--time=-[show time of last modification of any file in the directory]:property:->time' \
    '(* -)--help[display help information]' \
    '(* -)--version[display version information]' \
    '*:file:_files' && ret=0

  case $state in
    (time)
      local -a property
      property=(atime access use ctime status)
      _wanted property expl property compadd -a property && ret=0
      ;;
    (timestyle)
      local -a style desc
      style=(full-iso long-iso iso +)
      desc=('full-iso' 'long-iso' 'iso' '+FORMAT like `date'\''')
      _wanted -V style expl style compadd -d desc -a style && ret=0
      ;;
  esac

  return ret

else
  # based on $OSTYPE = solaris2.8
  local xdev='[skip directories on different filesystems]'
  if [[ ${commands[$words[1]]:-$words[1]} = *xpg4* ]]; then
    args=( -x$xdev )
  else
    args=( -d$xdev
      '-L[dereference symlinks]'
      "(-a)-o[do not add child directories' usage to parent's total]"
    )
  fi
  _arguments -s "$args[@]" \
    '(-s -o)-a[write counts for all files]' \
    '-k[use block size of 1k]' \
    '-r[notify about unreadable files/directories]' \
    '(-a)-s[only display total for each argument]' \
    '*:file:_files'
fi