mcnp_completion

#!/bin/bash
# vim: set tabstop=2:softtabstop=2:shiftwidth=2:noexpandtab 

_mcnp_completion() {

  # parse the COMP_WORDS and COMP_CWORDS to $cur $prev $word and $cword
  local cur prev words cword
  _init_completion -n = || return

  # ignore a space between keyword and equal sign
  # first alternative: "keyw =" or "keyw =val" : $prev = "keyw" and $cur = "=val" 
  if [[ $cur = "="* ]] ; then
    cur="$prev$cur"
  fi

  # second alternative: "keyw = " or "keyw = val" : $prev = "=" and $cur = "val" and word before is "keyw"
  if [[ $prev = "=" ]] ; then
    prev="${words[$cword-2]}="
  fi

  # first check, for some special cases
  # check, that $cur is "keyw=val" without any spaces
  if [[ $cur = [a-zA-Z]*=* ]] ; then
    # Split to keyword and value part
    local keyword value pattern
    keyword=${cur%%=*}
    value=${cur#*=}
    # check if keyword start with some string
    if [[ "inp" = $keyword* ]] ; then
      pattern='!*.@(i|inp)' 
    elif [[ "runtpe" = $keyword* ]] ; then 
      pattern='!@(*.r|runtp[e-z])?(.h5)'
    elif [[ "mctal" = $keyword* ]] ; then 
      pattern='!@(*.m|mcta[l-z])'
    elif [[ "xsdir" = $keyword* ]] ; then 
      pattern='!xsdir*'
    elif [[ "name" = $keyword* ]] ; then 
      local inpbase=$( echo $COMP_LINE | sed -En -e 's/\s*=\s*/=/g ; /\bin?p?=/{ s/^.*\bin?p?=(.*)(\s+.*)?$/\1/ ; s/(.*)\.[^.]*/\1/ ; p }' )
      local completion=${MCNP_PRERUN}${inpbase}.
      if [[ ( ! -z $inpbase ) && ( $completion = ${value}* ) ]] ; then
	COMPREPLY=($completion)
	return 0
      fi
      pattern='!*'
    else
      pattern='!*'
    fi
    compopt -o filenames
    COMPREPLY=($(compgen -f -X $pattern -o plusdirs  -- $value))
    return 0
  fi


  # Next check, if $prev is a keyword without a filename part
  # in this case, $cur is the corresponding filename (maybe empty), that needs to be expanded
  # in this case, use ANY filename, even for inp=
  # That way, it is possibly to expand any file
  if [[ $prev = [a-zA-Z]*= ]] ; then
    compopt -o filenames
    COMPREPLY=($(compgen -f -o plusdirs -o filenames -- $cur))
    return 0
  fi

  # guess the cpus available
  local cpu
  if [[ ! -z $MCNP_TASKS ]] ; then
    cpu=$MCNP_TASKS
  elif command -v nproc 2>&1 > /dev/null ; then
    cpu=$(nproc)
  else
    cpu=1
  fi


  # Finally expand any of the known keywords
  local -a words

  # all keywords that expect a file / direcory
  words="inp=;outp=;runtpe=;xsdir=;wwinp=;wwout=;wwone=;partinp=;linkin=;linkout=;ksental=;histp=;dumn1=;dumn2=;com=;comout=;plotm=;mctal=;meshtal=;mdata=;ptrac=;name=;srctp=;wssa=;rssa="
   
  
  # All other_options (upper case for MCNP 4?)
  words="${words};BALANCE ;C ;CN ;DEBUG ;DEV_TEST ;EOL;FATAL ;NOTEK ;PRINT ;TASKS $cpu ;"

  # don't insert space after word. Thus for files, the curser is positioned directly after the = sign
  # for the other_options, a space is inserted in the above string and that is seperated by a semicolon
  # set IFS accordingly
  compopt -o nospace
  local IFS=$';\n'

  # compgen filters all words that match $cur 
  COMPREPLY=( $(compgen -W "$words" -- $cur ) )
  return 0
}


complete -F _mcnp_completion mcnp
complete -F _mcnp_completion mcnp6