#compdef -K _expand_alias complete-word \C-xa

local word expl tmp pre sel what
local -a tmpa

eval "$_comp_setup"

if [[ -n $funcstack[2] ]]; then
  if [[ "$funcstack[2]" = _prefix ]]; then
    word="$IPREFIX$PREFIX$SUFFIX"
  else
    word="$IPREFIX$PREFIX$SUFFIX$ISUFFIX"
  fi
  pre=()
else
  local curcontext="$curcontext"

  if [[ -z "$curcontext" ]]; then
    curcontext="expand-alias-word:::"
  else
    curcontext="expand-alias-word:${curcontext#*:}"
  fi

  word="$IPREFIX$PREFIX$SUFFIX$ISUFFIX"
  pre=(_main_complete - aliases)
fi

zstyle -s ":completion:${curcontext}:" regular tmp || tmp=yes
case $tmp in
always) sel=r;;
yes|1|true|on) [[ CURRENT -eq 1 ]] && sel=r;;
esac
zstyle -T ":completion:${curcontext}:" global && sel="g$sel"
zstyle -t ":completion:${curcontext}:" disabled && sel="${sel}${(U)sel}"

tmp=
[[ $sel = *r* ]] && tmp=$aliases[$word]
[[ -z $tmp && $sel = *g* ]] && tmp=$galiases[$word]
[[ -z $tmp && $sel = *R* ]] && tmp=$dis_aliases[$word]
[[ -z $tmp && $sel = *G* ]] && tmp=$dis_galiases[$word]

if [[ -n $tmp ]]; then
  # We used to remove the quoting from the value in the parameter.
  # That was probably just an oversight: an alias is always replaced
  # literally.
  tmp=${tmp%%[[:blank:]]##}
  if [[ $tmp[1] = [[:alnum:]_] ]]; then
    tmpa=(${(z)tmp})
    if [[ $tmpa[1] = $word && $tmp = $aliases[$word] ]]; then
      # This is an active regular alias and the first word in the result
      # is the same as what was on the line already.  Quote it so
      # that it doesn't get reexanded on execution.
      #
      # Strictly we also need to check if the original word matches
      # a later word in the expansion and the previous words are
      # all aliases where the expansion ends in " ", but I'm
      # too lazy.
      tmp="\\$tmp"
    fi
  fi
  $pre _wanted aliases expl alias compadd -UQ -- ${tmp%%[[:blank:]]##}
elif (( $#pre )) && zstyle -t ":completion:${curcontext}:" complete; then
  $pre _aliases -s "$sel" -S ''
else
  return 1
fi