# datamash bash-completion
#
## Copyright (C) 2014-2020 Assaf Gordon <[email protected]>
##
## This file is part of GNU Datamash.
##
## This file is free software; as a special exception the author gives
## unlimited permission to copy and/or distribute it, with or without
## modifications, as long as this notice is preserved.
##
## This program is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
## implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
##

_datamash ()
{
  local cur prev words cword split=false
  _get_comp_words_by_ref cur prev words cword

  local modes="check crosstab groupby reverse rmdup transpose"
  local modes_re=${modes// /|}

  #NOTE: do not change the spaces (or indentation or backslashes)
  #      or the regex will fail.
  local groupby_ops="sum min max absmin absmax range \
count first last rand \
unique collapse countunique \
mean trimmean median q1 q3 iqr perc mode antimode \
pstdev sstdev pvar svar mad madraw \
pskew sskew pkurt skurt dpo jarque \
pcov scov ppearson spearson strbin"
 local groupby_ops_re=${groupby_ops// /|}

  local line_ops="base64 debase64 md5 sha1 sha256 sha512 \
round floor ceil trunc frac bin dirname basename extname barename cut"
  local line_ops_re=${line_ops// /|}

  local datamash_short_options="-C -f -g -H -i -s -t -W -z"

  local datamash_long_options="--full --group --header-in --header-out --headers
  --ignore-case --sort --no-strict --filler --field-separator --whitespace
  --zero-terminated --help --version --output-delimiter --skip-comments"

  local all_ops_re="$modes_re|$groupby_ops_re|$line_ops_re"

  # IF the previous word as an operator, the next parameter should
  # be a numeric value, so don't offer any completion.
  if [[ "$prev" =~ $all_ops_re ]] ; then
    return 0
  fi

  # Based on current parameteres, check which mode we're in.
  local suggest_modes=1
  local suggest_groupby_ops=1
  local suggest_line_ops=1
  local i=$((cword-1))

  while [ "$i" -gt 0 ] ; do
    local tmp_word=${words[$i]}

    if [[ "$tmp_word" =~ $modes_re ]] ; then
      suggest_modes=0
      case "$tmp_word" in
        crosstab|groupby) suggest_line_ops=0
      esac
    fi

    if [[ "$tmp_word" =~ $groupby_ops_re ]]; then
      suggest_modes=0
      suggest_line_ops=0
    fi
    # if the user specified -g, we're in "groupby" mode
    if [[ "$tmp_word" = "-g" ]] ; then
      suggest_modes=0
      suggest_line_ops=0
    fi

    if [[ "$tmp_word" =~ $line_ops_re ]]; then
      suggest_modes=0
      suggest_groupby_ops=0
    fi

    i=$((i-1))
  done

  # Options trump everything (if the user typed '-')
  if [[ "$cur" = "-"* ]] ; then
    COMPREPLY=( $(compgen -W \
        "$datamash_short_options $datamash_long_options" -- "$cur") )
    return 0
  fi

  # suggest other possibilities
  local suggest=""
  if [ "$suggest_modes" -eq 1 ] ; then
    suggest="$modes"
  fi
  if [ "$suggest_groupby_ops" -eq 1 ] ; then
    suggest="$suggest $groupby_ops"
  fi
  if [ "$suggest_line_ops" -eq 1 ] ; then
    suggest="$suggest $line_ops"
  fi

  COMPREPLY=( $(compgen -W "$suggest" -- "$cur") )
  return 0
}

complete -F _datamash datamash

# ex: ts=4 sw=4 et filetype=sh