#compdef -k complete-word \C-xn

# Main widget.

_next_tags() {
  eval "$_comp_setup"

  local ins ops="$PREFIX$SUFFIX"

  unfunction _all_labels _next_label

  _all_labels() {
    local gopt=-J len tmp pre suf ret=1 descr spec

    if [[ "$1" = -([12]|)[VJ] ]]; then
      gopt="$1"
      shift
    fi

    tmp=${argv[(ib:4:)-]}
    len=$#
    if [[ tmp -lt len ]]; then
      pre=$(( tmp-1 ))
      suf=$tmp
    elif [[ tmp -eq $# ]]; then
      pre=-2
      suf=$(( len+1 ))
    else
      pre=4
      suf=5
    fi

    while comptags -A "$1" curtag spec; do
      [[ "$_next_tags_not" = *\ ${spec}\ * ]] && continue
      _comp_tags="$_comp_tags $spec "
      if [[ "$curtag" = *:* ]]; then
        zformat -f descr "${curtag#*:}" "d:$3"
        _description "$gopt" "${curtag%:*}" "$2" "$descr"
        curtag="${curtag%:*}"

        "$4" "${(P@)2}" "${(@)argv[5,-1]}"
      else
        _description "$gopt" "$curtag" "$2" "$3"

        "${(@)argv[4,pre]}" "${(P@)2}" "${(@)argv[suf,-1]}" && ret=0
      fi
    done

    return ret
  }

  _next_label() {
    local gopt=-J descr spec

    if [[ "$1" = -([12]|)[VJ] ]]; then
      gopt="$1"
      shift
    fi

    if comptags -A "$1" curtag spec; then
      [[ "$_next_tags_not" = *\ ${spec}\ * ]] && continue
      _comp_tags="$_comp_tags $spec "
      if [[ "$curtag" = *:* ]]; then
        zformat -f descr "${curtag#*:}" "d:$3"
        _description "$gopt" "${curtag%:*}" "$2" "$descr"
        curtag="${curtag%:*}"
	set -A "$2" "${(P@)2}" "${(@)argv[4,-1]}"
      else
        _description "$gopt" "$curtag" "$2" "$3"
	set -A "$2" "${(@)argv[4,-1]}" "${(P@)2}"
      fi

      return 0
    fi

    return 1
  }

  if [[ "${LBUFFER%${PREFIX}}" = "$_next_tags_pre" ]]; then
    PREFIX="$_next_tags_pfx"
    SUFFIX="$_next_tags_sfx"
  else
    _next_tags_pre="${LBUFFER%${PREFIX}}"
    if [[ "$LASTWIDGET" = (_next_tags|list-*|*complete*) ]]; then
      PREFIX="$_lastcomp[prefix]"
      SUFFIX="$_lastcomp[suffix]"
    fi
  fi

  _next_tags_not="$_next_tags_not $_lastcomp[tags]"
  _next_tags_pfx="$PREFIX"
  _next_tags_sfx="$SUFFIX"

  if [[ -n "$compstate[old_insert]" ]]; then
    ins=1
  else
    ins=unambiguous
  fi

  _main_complete _complete _next_tags_completer

  [[ $compstate[insert] = automenu ]] && compstate[insert]=automenu-unambiguous
  [[ $compstate[insert] = *unambiguous && -n "$ops" &&
     -z "$_lastcomp[unambiguous]" ]] && compadd -Uns "$SUFFIX" - "$PREFIX"

  compstate[insert]="$ins"
  compstate[list]='list force'

  compprefuncs=( "$compprefuncs[@]" _next_tags_pre )
}

# Completer, for wrap-around.

_next_tags_completer() {
  _next_tags_not=

  _complete
}

# Pre-completion function.

_next_tags_pre() {

  # Probably `remove' our label functions. A better test would be nice, but
  # I think one should still be able to edit the current word between
  # attempts to complete it.

  if [[ -n $compstate[old_insert] && $WIDGET != _next_tags ]]; then
    compstate[old_list]=keep
    compstate[insert]=menu:2
    return 0
  elif [[ ${LBUFFER%${PREFIX}} != ${_next_tags_pre}* ]]; then
    unfunction _all_labels _next_label
    autoload -U _all_labels _next_label
  else
    compprefuncs=( "$compprefuncs[@]" _next_tags_pre )
  fi
}

_next_tags "$@"