# Configure the completion system.

emulate -L zsh
setopt extendedglob

local key
local compcontext=-default-

__ci_tidyup() {
  unfunction -m __ci_\* 2>/dev/null
  unfunction compinstall
  autoload -Uz compinstall
}

__ci_newline() {
  read -k \
    key"?${1:---- Hit newline to continue or \`q' to exit without saving --- }"
  print
  if [[ $key = [qQ] ]]; then
    print "compinstall aborted."
    __ci_tidyup
    return 1
  else
    return 0
  fi
}

typeset startline='# The following lines were added by compinstall'
typeset endline='# End of lines added by compinstall'
typeset ifile line fpath_line compinit_args opt detect basic line2
typeset -A styles
typeset match mbegin mend warn_unknown warn_old warn_comment output
integer lines_found

while getopts "do" opt; do
  case $opt in
    (d)
    # Detect an existing compinstall setup.
    detect=1
    ;;

    (o)
    # Output basic setup information only.
    basic=1
    ;;
  esac
done

#
# Check the user's .zshrc, if any.
#
# This relies on the stuff we find being only minimally edited from
# the stuff we originally saved.  A better way of doing this would
# almost certainly be to use the style mechanism directly:  save the
# current styles in a variable, delete all styles, read in and evaluate
# any styles found, manipulate styles directly using zstyle, write out
# using zstyle -L, and if necessary restore the original styles.  One
# day I may even do that.
#

__ci_test_ifile() {
  [[ -f $1 ]] && grep "$endline" $1 >/dev/null 2>&1
}

local foundold=false
if zstyle -s :compinstall filename ifile &&
  __ci_test_ifile $ifile; then
  foundold=true
else
  ifile=${ZDOTDIR:-~}/.zshrc
  if __ci_test_ifile ${ZDOTDIR:-~}/.compinstall; then
    ifile=${ZDOTDIR:-~}/.compinstall
    foundold=true
  elif __ci_test_ifile $ifile; then
    foundold=true
  fi
fi


if [[ -n $detect ]]; then
  __ci_tidyup
  [[ $foundold = true ]]
  return
fi


__ci_output() {
  print -r "$startline"
  [[ -n $output ]] && print -r "$output"
  if [[ -n $ifile ]]; then
    line="zstyle :compinstall filename ${(qq)ifile}"
    print -r "$line"
    eval "$line"
  fi

  [[ -n $fpath_line ]] && print -r "$fpath_line"

  print -r "
autoload -Uz compinit
compinit${compinit_args:+ $compinit_args}"

  print -r "$endline"
}


if [[ -n $basic ]]; then
  __ci_output
  __ci_tidyup
  return
fi

local newifile=$ifile
if [[ $foundold = true ]]; then
  if [[ $newifile != [~/]* ]]; then
    newifile=${ZDOTDIR:-~}/$newifile
    print "[Existing completion definition file is not absolute path:
updating to $newifile]"
  fi
  print "I have found completion definitions in $newifile.
If you want me to read these, just hit return.  Otherwise, edit the file
name to look for definitions somewhere else, or delete the whole line
in order not to use existing definitions."
  vared -ch -p 'file> ' newifile
  if [[ -n $newifile && $newifile != [/~]* ]]; then
    newifile=$PWD/$newifile
    print "[Not absolute path: updating to $newifile]"
  fi
  [[ -z $newifile || ! -f $newifile ]] && foundold=false
else
  print "I haven't found any existing completion definitions.
If you have some already defined by compinstall, edit the name of the
file where these can be found.  Note that this will only work if they
are exactly the form in which compinstall inserted them.  If you leave
the line as it is, or empty, I won't search."
  while true;  do
    vared -ch -p 'file> ' newifile || break
    if [[ -n $newifile && $newifile != [/~]* ]]; then
      newifile=$PWD/$newifile
      print "[Not absolute path: updating to $newifile]"
    fi
    if [[ -n $newifile && $ifile != $newifile ]]; then
      if __ci_test_ifile $newifile; then
        foundold=true
	break
      fi
      print "I couldn't find any definitions there.  Edit a new filename, or
leave the line blank to ignore it."
    else
      break
    fi
  done
fi
ifile=${~newifile}

if [[ $foundold = true ]]; then
  sed -n "/^[ 	]*$startline/,/^[ 	]*$endline/p" $ifile |
  # We can't use the default read behaviour to handle continuation lines
  # since it messes up internal backslashes.
  while read -r line; do
    # detect real continuation backslashes by checking there are an
    # odd number together.  i think this is reliable since the only
    # other way of quoting a backslash involves following it with
    # a closing quote.
    while [[ $line = *\\ ]]; do
      line2=${(M)line%%\\##}
      (( ${#line2} & 1 )) || break
      read -r line2 || break
      line="${line[1,-2]}$line2"
    done
    (( lines_found++ ))
    if [[ $line = *'$fpath'* ]]; then
      fpath_line=$line
      if [[ $line != *\) ]]; then
        while read -r line; do
          fpath_line="$fpath_line
$line"
          [[ $line = *\) ]] && break
        done
      fi
    elif [[ $line = (#b)[[:blank:]]#zstyle[[:blank:]]##(\'[^\']#\')\
[[:blank:]]##([^[:blank:]]##)[[:blank:]]##(*) ]]; then
      styles[$match[2]]="${styles[$match[2]]:+${styles[$match[2]]}
}${(Q)match[1]}
${match[3]}"
    elif [[ $line = [[:blank:]]#compconf* ]]; then
      warn_old=1
    elif [[ $line == $startline || $line == $endline ]]; then
      # no-op
    elif [[ $line = [[:blank:]]#\#* ]]; then
      warn_comment=1
    elif [[ $line = [[:blank:]]#compinit[[:blank:]]##(#b)([^[:blank:]]*) ]]
    then
      compinit_args=$match[1]
    elif [[ $line != [[:blank:]]# &&
      $line != [[:blank:]]#'autoload '*' compinit' &&
      $line != [[:blank:]]#compinit &&
      $line != [[:blank:]]#zstyle[[:blank:]]#:compinstall* ]]; then
      warn_unknown="${warn_unknown:+$warn_unknown
}$line"
    fi
  done
fi

#
# Print warnings about what we found in .zshrc.
#

if [[ -n $warn_old ]]; then
  print "\
WARNING: your configuration appears to contain commands for the 3.1.6
configuration system.  You will have to reconfigure from scratch and the
existing configuration commands will be overwritten.  If you wish to preserve
the old commands, you should quit, copy them somewhere else, then rerun
compinstall.  Sorry."
elif [[ -n $warn_unknown ]]; then
  print "\
WARNING: your configuration contains bits not understood by compinstall,
which will not be retained (shown below).  If you wish to retain these, you
should quit, copy them somewhere else, and then rerun compinstall.

$warn_unknown"
elif [[ -n $warn_comment ]]; then
  print "All the comments in your configuration section will be lost.
If you want to keep them, you should copy them somewhere else first."
elif (( ! $lines_found )); then
  print "Starting a new completion configuration from scratch."
  if [[ -n $ifile && ! -d $ifile ]]; then
    print -n "This will be "
    if [[ ! -f $ifile ]]; then
      print "written to the new file $ifile."
    elif [[ ! -w $ifile ]]; then
      print "written to the file ~/.compinstall for copying to $ifile."
      ifile=$HOME/.compinstall
    else
      print "appended to the file $ifile.  It is up to you to ensure
that these lines are actually executed.  They will not be if your .zshrc
usually returns before the end."
    fi
  fi
fi
print "Note that you will be given a chance to save the new setup
somewhere else at the end."


__ci_newline || return 1


typeset d compdir subdirs lines

#
# Make sure we have the completion functions in $fpath.
#

__ci_set_compdir() {
  for d in $*; do
    # If we find both the functions more than once, assume the later
    # one is the standard set.
    if [[ -f $d/compinit && -f $d/compdump ]]; then
      compdir=$d
    fi
  done
}

__ci_set_compdir $fpath

if [[ -d $compdir/Base/Core ]]; then
  subdirs=2
elif [[ -d $compdir/Base ]]; then
  subdirs=1
  ### compdir=${compdir:h}
fi

if [[ -z $compdir ]]; then
  # Start up a new zsh and get its default fpath.  If some swine has
  # tinkered with this in /etc/zshenv we're out of luck.
  lines=(${(f)"$(zsh -fc 'print -l $ZSH_VERSION $fpath')"})
  line=$lines[1]
  shift lines
  # If the zsh in that path isn't right, maybe the user's shell is elsewhere.
  if [[ $line != $ZSH_VERSION && -x $SHELL ]]; then
    lines=(${(f)"$($SHELL -fc 'print -l $ZSH_VERSION $fpath' 2>/dev/null)"})
    line=$lines[1]
    shift lines
  fi
  if [[ $line != $ZSH_VERSION ]]; then
    print "Hmmm, the zsh in your path is not what's running, nor is \$SHELL.
That's bad.
"
  fi
  __ci_set_compdir $lines
  if [[ -n $compdir ]]; then
    print "\
I've found the completion directories and will add them to your \$fpath,
but they should already be there at shell startup, so something (probably
an unconditional assignment in a startup file) is taking them out.  You
might want to check this, although what I'm doing should work."
    if [[ -n $fpath_line ]]; then
      print "\

What's more, there is already an \$fpath assignment in your completion
setup.  This gives me cause for concern.  I will override this, but don't
be surprised if it doesn't go according to plan.  If you have not
initialised completion in this shell, you should do so, then run
compinstall again."
    fi
  fi
  if [[ $subdirs = 2 ]]; then
    fpath_line=($compdir/[A-Z]*/[A-Z]*)
    fpath_line="fpath=($fpath ${(F)fpath_line})"
  elif [[ -n $subdirs ]]; then
    fpath_line=($compdir/[A-Z]*)
    fpath_line="fpath=($fpath ${(F)fpath_line})"
  fi
else
  if [[ $subdirs = 2 ]]; then
    print "Completion directories $compdir/*/*
are already in your \$fpath, good."
  elif [[ -n $subdirs ]]; then
    print "Completion directories $compdir/*
are already in your \$fpath, good."
  else
    print "Completion directory $compdir
is already in your \$fpath, good."
  fi
  if [[ -n $fpath_line ]]; then
    print "I shall keep the existing \$fpath=( ... ) assignment."
  fi
fi

if [[ -z $compdir ]]; then
  print "\
The zsh in your path doesn't seem to have completion directories in the
function autoload path (\$fpath).  This suggests the shell wasn't installed
for completion.  If you want to use it, you will need to locate all the
completion functions yourself and install them in your \$fpath.  I will
continue, but don't expect this to have much effect until you do.

If you are planning to continue using the old compctl system for
completion, compinstall won't do you any good anyway."
fi

__ci_newline || return 1


#
# Code for changing styles
#

typeset defcontext=":completion:*"
typeset curcontext=$defcontext

#
# Utility functions
#

#
# Get the style $1 for $curcontext into $2.
#
__ci_get_this_style() {
  typeset -A tassoc
  local style=$1 scalar=$2

  tassoc=(${(f)styles[$style]})
  eval "$scalar=\${tassoc[\$curcontext]}"
}

#
# Set the style $1 for $curcontext using scalar $2 for the value for this
# context.  If $2 is null, delete the context (this may not be correct for
# all styles).  Don't do any extra quotation.
# $2 gives the name of the scalar for symmetry with __ci_get_this_style.
#
__ci_set_this_style() {
  local style=$1 scalar=$2 k
  typeset -A tassoc
  tassoc=(${(f)styles[$style]})

  if [[ -n ${(P)scalar} ]]; then
    tassoc[$curcontext]=${(P)scalar}
  else
    unset "tassoc[$curcontext]"
  fi

  styles[$style]=
  for k in ${(ko)tassoc}; do
    styles[$style]="${styles[$style]:+$styles[$style]
}$k
${tassoc[$k]}"
  done
}

#
# Functions displaying menus
#

__ci_change_context() {
  clear
  print "\
             *** compinstall: change context ***

The context tells the completion system under what circumstances your
value will be used.  It has this form:
  :completion:<function-name>:<completer>:<command>:<argument>:<tag>
See the documentation for more detail on each of these components.  The
default context \`$defcontext' matches everywhere in completion, unless you
define a more specific pattern which matches the completion context being
used. \`More specific' means either a string instead of a pattern, or a
longer pattern instead of a shorter pattern.

Edit a new context, or leave the line blank to reset the context to the
default value.  Note that you do not require quotes around the context,
which will automatically be added later.  Line editing and history are
available.
"

  vared -eh -p 'context> ' curcontext
  [[ -z $curcontext ]] && curcontext=$defcontext
}


__ci_toggle_completer() {
  # used locally within __ci_do_completers
  if [[ -n $completers[$1] ]]; then
    completers[$1]=
  else
    completers[$1]=1
  fi
}

__ci_do_minor_completer_options() {
  # Set the options for the minor completers.
  local key cond word olist omenu moriginal aspace tmparr
  __ci_get_this_style condition cond
  [[ -n $cond ]] && cond=${(Q)cond}
  __ci_get_this_style word word
  __ci_get_this_style old-list olist
  __ci_get_this_style old-menu omenu
  __ci_get_this_style match-original moriginal
  __ci_get_this_style add-space aspace

  while true; do

    # insert-unambiguous can be handled somewhere else.
    clear
    print "\
              *** compinstall: minor completer options ***

Current context: $curcontext

l.     Set options for _list: condition for delay and comparison.
o.     Set options for _oldlist: when to keep old list.
m.     Set options for _match: whether to assume a \`*' at the cursor.
p.     Set options for _prefix: whether to add a space before the suffix.

q.     Return to the previous menu without saving.
0.     Done setting completer options.
"

    read -k key'?--- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      [lL]) print "\
You can set a condition under which the _list completer will delay completion
until the second keypress.  It should evaluate to a number; a non-zero value
turns this behaviour on.  It can include parameters, in particular NUMERIC
to refer to a numeric argument.  For example, \`NUMERIC != 1' forces the
delay unless you give an argument 1 to the command.  Leave it blank to
assume the condition is true."
            vared -eh -c -p 'condition> ' cond
	    print -n "
_list will usually compare the contents of the entire line with its previous
contents to decided if it has been changed since the last keypress.  You
can instead perform this comparison on just the current word, ignoring
the rest of the command line.  Do you want to do this? (y/n) [n] "
	    word=
            read -q key && word=true
	    print
	    ;;
      [oO]) print "\
_oldlist can keep a generated completion list for reshowing in the usual
way, e.g. with ^D, even if the list was generated by some special completion
command.  The default behaviour of _oldlist is to show this list if it was
not already visible, otherwise to generate the standard completion listing,
but you can force it always to be shown, or make it never shown.
Alternatively, you can specify a list of completers for which _oldlist will
be used.  Choose:

d.    Default behaviour.
a.    Always show old list.
n.    Never show old list.
s.    Specify a list of completers.
"

            while true; do
	      read -k key'?--- Hit selection --- '
	      print
	      case $key in
		[dD]) olist=
		   ;;
		[aA]) olist=always
		      ;;
		[nN]) olist=never
		      ;;
		[sS]) olist=
		      tmparr=(_complete _approximate _correct _match _expand)
		      while true; do
			clear
			print "\
     *** compinstall:  choosing completers to have _oldlist behaviour ***

Type any of:

1.  _complete
2.  _approximate
3.  _correct
4.  _match
5.  _expand

or 0 to end, or - to delete the last choice."
			if [[ -n $olist ]]; then
			  print "\
Current choices:
  $olist"
			fi
			read -k key'?--- Hit selection --- '
			print
			case $key in
			  0) break
			     ;;
			  -) olist=(${olist[1,-2]})
			     ;;
			  [1-5]) olist=($olist $tmparr[$key])
			         ;;
			esac
                      done
		      ;;
		*) print "Type one of d, a, n or s."
		   continue
		   ;;
	      esac
	      break
	    done

	    print -n "
_oldlist can keep the old completion list for use in menu completion, e.g. by
repeatedly hitting tab, even if the list was generated by some special
completion command.  This is the default behaviour of _oldlist, but
you can turn it off, so that hitting tab would use the standard completion
list.

Do you want to turn it off? (y/n) [n] "
            omenu=
	    read -q key && omenu=false
	    ;;
      [mM]) print "\
The _match completer will usually assume there is a \`*' at the cursor
position when trying pattern matches.  For example, \`f*n<TAB>e' would
be able to complete to \`filename', not just to patterns matching \`f*ne'.
(Note that this assumes you have the option COMPLETE_IN_WORD set, else all
completion takes place at the end of the word.)  You can tell _match not
to assume there is a \`*', or to try first without the \`*', then with it.
Type one of:

a.     Always assume \`*' at cursor position.
n.     Never assume \`*' at cursor position.
w.     Try without the \`*', then with it if that fails."
            while true; do
	      read -k key'?--- Hit selection --- '
	      print
	      case $key in
		a) moriginal=
		   ;;
		n) moriginal=only
		   ;;
		w) moriginal=both
		   ;;
		*) print "Type one of a, n or w."
		   continue
		   ;;
	      esac
	      break
	    done
            ;;
      [pP]) print -n "\
The _prefix completer completes only what is behind the cursor, ignoring
completely what is after, even if there is no space at the cursor position.
However, you can force it to add a space between the resulting completion
and the part ignored.  For example, \`f<TAB>bar' might expand to \`filebar'
without this, and to \`file bar' with it.  Do wish _prefix to add the
space? (y/n) [n] "
            aspace=
            read -q key && aspace=true
	    ;;
      [qQ]) return 1
	    ;;
    esac

  done

  [[ -n $cond && $cond != [[:alnum:]]## ]] && cond=${(qq)cond}
  __ci_set_this_style condition cond
  __ci_set_this_style word word
  __ci_set_this_style old-list olist
  __ci_set_this_style old-menu omenu
  __ci_set_this_style match-original moriginal
  __ci_set_this_style add-space aspace

  return 0
}

__ci_do_minor_completers() {
  # Set the minor completers not handled by __ci_do_completers.
  # Called within __ci_do_completers, so inherits the environment.
  # It's only divided off to keep the menus short.

  local key

  while true; do

    clear
    print "\
              *** compinstall: minor completer menu ***

Current context: $curcontext

The following completers are available.  Those marked \`(*)' are already
set for the context shown above.  Note none of these are required for
normal completion behaviour.

1. ${${completers[_ignored]:+(*)}:-   } _ignored: $ckeys[_ignored]
2. ${${completers[_list]:+(*)}:-   } _list:    $ckeys[_list]
3. ${${completers[_oldlist]:+(*)}:-   } _oldlist: $ckeys[_oldlist]
4. ${${completers[_match]:+(*)}:-   } _match:   $ckeys[_match]
5. ${${completers[_prefix]:+(*)}:-   } _prefix:  $ckeys[_prefix]

o.     Set options for the completers above.
q.     Return without saving.
0.     Done setting minor completers.
"
    read -k key'?--- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      1) __ci_toggle_completer _ignored
	 if [[ -n $completers[_ignored] ]]; then
	   print "\
I am inserting the \`ignored' completer immediately after normal
completion.  You can move it later in the list by hand, if you prefer, so
that ignored completions are only used after, for example, approximations.
To do this, edit $ifile, look for the zstyle ... completers line, and
move \`_ignored' to where you want it.  This will be retained if you use
compinstall again provided you don't go into the completers menu.
"
	   # TODO: we could be more careful about keeping the user's
	   # order, particularly with multiple completers.
           read -k key'?--- Hit any key to continue --- '
	   print
	 fi
	 ;;
      2) __ci_toggle_completer _list
	 ;;
      3) __ci_toggle_completer _oldlist
	 ;;
      4) __ci_toggle_completer _match
	 ;;
      5) __ci_toggle_completer _prefix
	 ;;
      o) __ci_do_minor_completer_options
	 ;;
      q) return 1
	 ;;
    esac

  done

  return 0
}

__ci_do_completer_options() {
  # Set options for the main completers; called from __ci_do_completers.

  local maxe errors prompt glob subst compl cond

  __ci_get_this_style max-errors errors
  __ci_get_this_style prompt prompt
  [[ -n $prompt ]] && prompt=${(Q)prompt}
  __ci_get_this_style glob glob
  [[ -n $glob ]] && glob=${(Q)glob}
  __ci_get_this_style substitute subst
  [[ -n $subst ]] && subst=${(Q)subst}
  __ci_get_this_style completions compl
  [[ -n $compl ]] && compl=${(Q)compl}

  while true; do

    clear
    print "\
              *** compinstall: completer options ***

Current context: $curcontext

The following options are available.  Note that these require the relevant
completers to be present, as set in the menu above this one.

a.     Set options for approximation or correction.
e.     Set options for expansion.
q.     Return without saving.

0.     Done setting options.
"

    read -k key'?--- Hit selection --- '
    print

    # We handle approximation and correction together to avoid having
    # to be too particular about context.
    case $key in
      a) clear
         print "\
Approximation and correction can correct the errors in what you have typed,
up to a maximum number of errors which you can specify.  Each \`error'
is the omission of a character, the addition of a superfluous character,
the substitution of one character by an incorrect one, or transposition of
two different characters.

Current context: $curcontext

To have different values for approximation and correction, you should
change the context appropriately.  For approximation, use
\`:completion:*:approximate:*' and for correction use
\`:completion:*:correct:*'.

Enter maximum number of errors allowed:
"
         maxe=
	 while true; do
	   vared -eh -c -p "number> " maxe
	   [[ $maxe = [[:digit:]]## ]] && break
	   print "Please enter a number"
	   maxe=
	 done
	 while true; do
	   print "\nSelect behaviour of numeric prefix.

1.     Numeric prefix is not used by approximation or completion.
2.     Numeric prefix, if provided, gives max number of errors allowed,
       replacing the number you just typed for that one completion.
3.     Numeric prefix, if provided, prevents approximation or completion
       from taking place at all for that one completion.
"
           read -k -- key'?--- Hit selection --- '
	   print
	   [[ $key = [123] ]] || continue
	   case $key in
             2) maxe="$maxe numeric"
		;;
	     3) maxe="$maxe not-numeric"
		;;
	   esac
	   print "
You can edit a prompt which will appear above lists of corrections.  The
string \`%e' inside the prompt will be replaced with the number of errors
found.  Leave blank for no prompt.  Quotation marks will be added
automatically."
	   vared -eh -c -p "prompt> " prompt
	   break
	 done
	 errors=$maxe
	 ;;
      e) while true; do
           clear
           print "\
The _expand completer can be tuned to perform any of globbing (filename
generation), substitution (anything with a \`\$' or backquote), or
normal completion (which is useful for inserting all possible completions
into the command line).  For each feature, a 1 turns it on, while a 0 turns
it off; if the feature is unset, that expansion will *not* be performed.

You can also give more complicated mathematical expressions, which can use
the parameter NUMERIC to refer to the numeric argument.  For example, the
expression \`NUMERIC == 2' means that the expansion takes effect if you
type ESC-2 (Emacs mode) or 2 (Vi command mode) before the expansion.
Quotes will be added automatically as needed.

g.     Set condition to perform globbing: ${glob:-unset}
s.     Set condition to perform substitution: ${subst:-unset}
c.     Set condition to perform completion: ${compl:-unset}
0.     Done setting conditions (will not be saved until you leave options)
"
           read -k key'?--- Enter selection --- '
	   print

	   case $key in
	     g) vared -eh -c -p 'globbing condition> ' glob
		;;
	     s) vared -eh -c -p 'substitution condition> ' subst
		;;
	     c) vared -eh -c -p 'completion condition> ' compl
		;;
	   esac

	   [[ $key = 0 ]] && break

         done
	 ;;
      q) return 1
	 ;;
    esac

    [[ $key = 0 ]] && break
  done

  __ci_set_this_style max-errors errors
  [[ -n $prompt ]] && prompt=${(qq)prompt}
  __ci_set_this_style prompt prompt
  [[ -n $glob && $glob != [[:alnum:]]## ]] && glob=${(qq)glob}
  __ci_set_this_style glob glob
  [[ -n $subst && $subst != [[:alnum:]]## ]] && subst=${(qq)subst}
  __ci_set_this_style substitute subst
  [[ -n $compl && $compl != [[:alnum:]]## ]] && compl=${(qq)compl}
  __ci_set_this_style completions compl

  key=
  return 0
}

__ci_do_completers() {
  # Set the completers for the current context.
  # This is mostly done via a series of toggles.

  typeset -A completers ckeys
  local c clist newc
  __ci_get_this_style completer newc
  for c in ${=newc}; do
    completers[$c]=1
  done
  if (( ${#completers} == 0 )); then
    completers[_complete]=1
    completers[_ignored]=1
  fi
  clist=(_list _oldlist _menu _expand _complete _ignored
         _match _correct _approximate _prefix)

  # TODO: these are a bit brief, so could provide some more detailed help.
  ckeys=(_complete 'Basic completion.'
         _approximate
'Approximate completion:  completion with correction of existing word.'
         _correct
'Correction:  correct existing word, no completion.'
         _expand
'Expansion: use globbing and parameter substitution, if possible.'

	 _ignored
'Use patterns that were previously ignored if no matches so far.'
         _list
'Only list matches until the second time you hit TAB.'
         _oldlist
'Keep matches generated by special completion functions.'
        _match
'If completion fails, retry with pattern matching.'
         _prefix
'If completion fails, retry ignoring the part after the cursor.'
         )

  # TODO: You'll need to handle the bindkey to make _expand work.
  # TODO: _prefix completer should make sure completeinword is set.

  while true; do

    clear
    print "\
              *** compinstall: completer menu ***

Current context: $curcontext

The following completers are available.  Those marked \`(*)' are already
set for the context shown above.  If none are selected, the completers will
not be set for this context at all.

1. ${${completers[_complete]:+(*)}:-   } $ckeys[_complete]
2. ${${completers[_approximate]:+(*)}:-   } $ckeys[_approximate]
3. ${${completers[_correct]:+(*)}:-   } $ckeys[_correct]
4. ${${completers[_expand]:+(*)}:-   } $ckeys[_expand]

o.     Set options for the completers above.
m.     Set completers that modify the behaviour of the four main ones above.
q.     Return without saving.
0.     Done setting completers.
"
    read -k key'?--- Hit selection --- '
    print

    case $key in
      1) __ci_toggle_completer _complete
	 ;;
      2) __ci_toggle_completer _approximate
	 ;;
      3) __ci_toggle_completer _correct
	 ;;
      4) __ci_toggle_completer _expand
	 ;;
      [mM]) __ci_do_minor_completers || return
            continue
	    ;;
      [oO]) __ci_do_completer_options || return
            continue
	    ;;
      q) return 1
	 ;;
    esac

    [[ $key = 0 ]] && break
  done

  newc=
  for c in $clist; do
    [[ -n $completers[$c] ]] && newc="${newc:+$newc }$c"
  done
  [[ -z $newc ]] && newc="''"
  __ci_set_this_style completer newc
}

__ci_toggle_matcher() {
  # Toggle on/off the matcher in array $1 for element $2
  if [[ ${${(P)1}[$2]} = ' ' ]]; then
    # toggle on
    eval "${1}[$2]=$2"
    if [[ $1 = n* ]]; then
      # no matcher turned on, turn off the others
      c_list[$2]=' '
      C_list[$2]=' '
      p_list[$2]=' '
      s_list[$2]=' '
    else
      # something else turned on, turn off no matcher
      n_list[$2]=' '
    fi
    return 0
  else
    # toggle off
    eval "${1}[$2]=' '"
    if [[ $c_list[$2] == ' ' && $C_list[$2] == ' ' && \
	  $p_list[$2] == ' ' && $s_list[$2] == ' ' ]]; then
      a_or_r[$2]=' '
    fi
    return 1
  fi
}

__ci_do_matchers() {
  # Set matchers via the matcher-list style.
  # We just offer a pre-programmed set of possible matchers, but these
  # cover the most common usages for matchers in a general context.
  # More specific use of matchers is usually covered by completion functions.

  local mlist m_ci m_pw m_sub c_list C_list p_list s_list pw_seps key key2 elt
  local pw_dstar a_or_r i
  integer eltcnt lastnz

  __ci_get_this_style matcher-list mlist
  # $mlist is the once and future list of matchers.  We don't quote it
  # until the end; the eval effectively does de-quoting.
  eval "mlist=($mlist)"
  # ?_list say whether the four possible matchers are set for passes 1,
  # 2, 3, 4, in an easy-to-read manner, i.e. the Nth part of the string
  # is one of N (on) or space (off).
  a_or_r="    "                 # replace by default
  n_list="    "			# null completion, i.e. standard
  c_list="    "			# case match one way
  C_list="    "			# case match both ways
  p_list="    "			# partial word completion
  s_list="    "			# substring completion
  # $pw_seps gives the separators used for partial-word completion
  # by element of the matcher list; these can be edited separately.
  pw_seps=('._-' '._-' '._-' '._-')
  pw_dstar=('' '' '' '')

  # See what's in the matcher initially.  If these have been edited,
  # we're in trouble, but that's pretty much true of everything.
  for (( eltcnt = 1; eltcnt <= $#mlist; eltcnt++ )); do
    [[ $mlist[eltcnt] == "+"* ]] && a_or_r[$eltcnt]='+'
    [[ -z $mlist[$eltcnt] ]] && n_list[$eltcnt]=$eltcnt
    # Accept the old form of lower/upper correspondence, but we'll
    # output the new one instead.
    [[ $mlist[$eltcnt] = *"m:{a-z}={A-Z}"* ]] && c_list[$eltcnt]=$eltcnt
    [[ $mlist[$eltcnt] = *"m:{[:lower:]}={[:upper:]}"* ]] &&
      c_list[$eltcnt]=$eltcnt
    [[ $mlist[$eltcnt] = *"m:{a-zA-Z}={A-Za-z}"* ]] && C_list[$eltcnt]=$eltcnt
    [[ $mlist[$eltcnt] = *"m:{[:lower:][:upper:]}={[:upper:][:lower:]}"* ]] &&
      C_list[$eltcnt]=$eltcnt
    # For partial word stuff, we use backreferences to find out what
    # the set of separators was.
    if [[ $mlist[$eltcnt] = (#b)*"r:|["([^\]]#)"]=*"#" r:|=*"* ]]; then
      p_list[$eltcnt]=$eltcnt
      pw_seps[$eltcnt]=${match[1]}
      [[ $mlist[$eltcnt] = *"=**"* ]] && pw_dstar[$eltcnt]='*'
    fi
    # Just look for the left matcher for substring, since the right matcher
    # might have been handled as part of a partial-word spec.
    [[ $mlist[$eltcnt] = *"l:|=*"* ]] && s_list[$eltcnt]=$eltcnt
  done

  while true; do
    clear
    print "\
              *** compinstall: matcher menu ***

\`Matchers' compare the completion code with the possible matches in some
special way.  Numbers in parentheses show matchers to be tried and the order.
The same number can be assigned to different matchers, meaning apply at the
same time.  Omit a sequence number to try normal matching at that point.
A \`+' in the first line indicates the element is added to preceding matchers
instead of replacing them; toggle this with \`t'.  You don't need to set
all four, or indeed any matchers --- then the style will not be set.

   ($a_or_r)\
   \`+' indicates add to previous matchers, else replace
n. ($n_list)\
 No matchers; you may want to try this as the first choice.
c. ($c_list)\
 Case-insensitive completion (lowercase matches uppercase)
C. ($C_list)\
 Case-insensitive completion (lower/uppercase match each other)
p. ($p_list)\
 Partial-word completion:  expand 'f.b' to 'foo.bar', etc., in one go.
          You can choose the separators (here \`.') used each time.
s. ($s_list)\
 Substring completion:  complete on substrings, not just initial
          strings.  Warning: it is recommended this not be used for element 1.

t.        Toggle replacing previous matchers (\` ' at top) or add (\`+')
q.        Return without saving.
0.        Done setting matchers.
"

    read -k key'?--- Hit selection --- '
    print

    if [[ $key = [nNcCpPsS] ]]; then
      while true; do
	read -k key2'?Set/unset for element number (1234)? '
	print
	[[ $key2 = [1234] ]] && break
	print "Only 1, 2, 3 and 4 are handled."
      done
    fi

    case $key in
      [nN]) __ci_toggle_matcher n_list $key2
         if [[ $n_list[$key2] != ' ' ]]; then
	 fi
         ;;
      c) __ci_toggle_matcher c_list $key2
	 ;;
      C) __ci_toggle_matcher C_list $key2
	 ;;
      [pP]) if __ci_toggle_matcher p_list $key2; then
	      print "\
Edit the set of characters which terminate partial words.  Typically
these are punctuation characters, such as \`.', \`_' and \`-'.
The expression will automatically be quoted.
"
              vared -eh -p 'characters> ' -c 'pw_seps['$key2']'
	      # Paranoia: we don't know if there's a ']' in that string,
	      # which will wreck the spec unless it's at the start.  Other
	      # quotes are OK, since they are picked up at the ${(qq)...}
	      # step.
	      if [[ $pw_seps[$key2] = *']'* ]]; then
		pw_seps[$key2]="]${pw_seps[$key2]//\\\]}"
	      fi
	      print -n "
You can allow the partial-word terminators to be matched in the pattern,
too:  then  for example \`c.u' would expand to \`comp.source.unix', whereas
usually you would need to type an extra intervening dot.  Do you wish the
terminators to be matched in this way? (y/n) [n] "
              pw_dstar[$key2]=
	      read -q key && pw_dstar[$key2]='*'
	    fi
	    ;;
      [tT])
	    read -k key2'?Toggle augment/replace for elements number (1234)? '
	    if [[ $key2 == [1234] ]]; then
	      if [[ $a_or_r[$key2] == ' ' ]]; then
	        a_or_r[$key2]='+'
	      else
	        a_or_r[$key2]=' '
	      fi
	    else
	      print "Only 1, 2, 3 and 4 are handled."
	    fi
	    ;;
      [sS]) __ci_toggle_matcher s_list $key2
	    ;;
      [qQ]) return 1
	 ;;
    esac

    [[ $key = 0 ]] && break
  done

  # Keep track of the last element which was non-empty; all the rest
  # are junked.
  lastnz=0

  # Now we just reverse the first for-loop, looking for set matchers
  # and reconstructing the elements of the matcher array.
  for (( eltcnt = 1; eltcnt <= 4; eltcnt++ )); do
    elt=
    [[ $c_list[$eltcnt] != ' ' ]] &&
      elt="${elt:+$elt }m:{[:lower:]}={[:upper:]}"
    [[ $C_list[$eltcnt] != ' ' ]] &&
      elt="${elt:+$elt }m:{[:lower:][:upper:]}={[:upper:][:lower:]}"
    [[ $p_list[$eltcnt] != ' ' ]] &&
      elt="${elt:+$elt }r:|[${pw_seps[$eltcnt]}]=*${pw_dstar[$eltcnt]}\
 r:|=*${pw_dstar[$eltcnt]}"
    if [[ $s_list[$eltcnt] != ' ' ]]; then
      if [[ $elt = *"r:|=*"* ]]; then
	elt="${elt:+$elt }l:|=*"
      else
	elt="${elt:+$elt }l:|=* r:|=*"
      fi
    fi
    [[ $a_or_r[$eltcnt] != ' ' ]] && elt="+$elt"
    [[ -n $elt || $n_list[$eltcnt] != ' ' ]] && lastnz=$eltcnt
    mlist[$eltcnt]=$elt
  done

  if (( ! $lastnz )); then
    # No matchers set, so just make the style empty: __ci_set_this_style
    # will omit it completely.
    mlist=
  else
    # Quote the entire list: this correctly quotes element by element,
    # praise be to Sven.
    mlist=(${(qq)mlist[1,$lastnz]})
    # Make it a scalar just for safety's sake.
    mlist="$mlist"
  fi
  __ci_set_this_style matcher-list mlist

  return 0
}

__ci_do_list_format() {
  local key format groupn verbose listp autod haslistp
  __ci_get_this_style format format
  [[ -n $format ]] && format=${(Q)format}
  __ci_get_this_style group-name groupn
  __ci_get_this_style verbose verbose
  __ci_get_this_style list-prompt listp
  [[ -n $listp ]] && haslistp=1
  listp=${(Q)listp}
  __ci_get_this_style auto-description autod
  [[ -n $autod ]] && autod=${(Q)autod}

  while true; do
    clear
    print "\
       *** compinstall: order and descriptions in completion lists ***
Type the appropriate number for more information on how this would affect
listings.

1.  Print a message above completion lists describing what is being
    completed.

2.  Make different types of completion appear in separate lists.

3.  Make completion verbose, using option descriptions etc. (on by default).

4.  Make single-valued options display the value's description as
    part of the option's description.

q.  Return without saving.
0.  Done setting options for formatting of completion lists.
"

    read -k key'?--- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      1) print "\
You can set a string which is displayed on a line above the list of matches
for completions.  A \`%d' in this string will be replaced by a brief
description of the type of completion.  For example, if you set the
string to \`Completing %d', and type ^D to show a list of files, the line
\`Completing files' will appear above that list.  Enter an empty line to
turn this feature off.  If you enter something which doesn't include \`%d',
then \`%d' will be appended.  Quotation will be added automatically.
"
         vared -eh -p 'description> ' -c format
	 if [[ -n $format && $format != *%d* ]]; then
	   [[ $format = *[[:blank:]] ]] || format="$format "
	   format="$format%d"
	 fi
	 ;;
      2) print "\
Normally, all possible completions are listed together in a single list, and
if you have set a description with 1) above, the descriptions are listed
together above that.  However, you can specify that different types of
completion appear in separate lists; any description appears above its
own list.  For example, external commands and shell functions would appear
in separate lists when you are completing a command name.  Do you
want to turn this on?
"
         while true; do
           read -k key'?[y]es, [n]o, [k]eep old setting? '
	   print
	   [[ $key = [yYnNkK] ]] && break
	 done
	 case $key in
	   [yY]) groupn="''"
		 ;;
	   [nN]) groupn=
		 ;;
	 esac
	 ;;
      3) print "By default, completion uses a \`verbose' setting.  This
affects different completions in different ways.  For example,  many
well-known commands have short, uninformative option names; in some cases,
completion will indicate what the options do when offering to complete them.
If you prefer shorter listings you can turn this off.  What setting to
you want?
"
          while true; do
            read -k key'?[v]erbose, [n]ot verbose, [k]eep old setting? '
            print
            [[ $key = [vVnNkK] ]] && break
          done
          case $key in
	    # might as well be explicit, particularly since it's
	    # the only way to override an existing `false' value.
	    [vV]) verbose=true
		  ;;
	    [nN]) verbose=false
		  ;;
          esac
	 ;;
      4) print "\
Many commands have options which take a single argument.  In some cases,
completion is not set up to describe the option even though it has a
description for the argument.  You can enter a string containing \`%d',
which will be replaced by the description for the option.  For
example, if you enter the string \`specify: %d', and an option -ifile
exists which has an argument whose description is \`input file', then the
description \`specify: input file' will appear when the option itself
is listed.  As this long explanation suggests, this is only occasionally
useful.  Enter an empty line to turn this feature off.  If you enter
something which doesn't include \`%d', then \`%d' will be appended.
Quotation will be added automatically.
"
         vared -eh -p 'auto-description> ' -c autod
         if [[ -n $autod && $autod != *%d* ]]; then
	   [[ $autod = *[[:blank:]] ]] || autod="$autod "
	   autod="$autod%d"
         fi
	 ;;
      q) return 1
	 ;;
    esac
  done

  [[ -n $format ]] && format=${(qq)format}
  __ci_set_this_style format format
  __ci_set_this_style group-name groupn
  __ci_set_this_style verbose verbose
  [[ -n $autod ]] && autod=${(qq)autod}
  __ci_set_this_style auto-description autod
}

__ci_do_insertion() {
  local key insertu original # sort

  __ci_get_this_style insert-unambiguous insertu
  __ci_get_this_style original original

  while true; do
    clear
    print "\
          *** compinstall: options for inserting completions ***

1.   In completers that change what you have already typed, insert any
     unambiguous prefix rather than go straight to menu completion.

2.   In completers which correct what you have typed, keep what you
     originally typed as one of the list of possible completions.

q.   Return with saving.
0.   Done setting options for insertion.
"
    read -k key'?-- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      1) print "\
The completers which do pattern matching and correction often alter the
string which is already on the line, in the first case because it was a
pattern and in the second case because what you typed was wrong.
Since the possible completions can bear little or no resemblance to one
another in those cases, so that typing extra characters to resolve the
completion doesn't make much sense, menu completion is usually turned on
straight away to allow you to pick the completion you want.  This style
tells completion that if there is a common, unambiguous prefix in this
case, you would prefer that to be inserted rather than going straight
to menu completion.  Do you want this?
"
         while true; do
           read -k key'?[y]es, [n]o, [k]eep old setting? '
	   print
	   [[ $key = [yYnNkK] ]] && break
	 done
	 case $key in
	   [yY]) insertu=true
	         ;;
	   [nN]) insertu=false
		 ;;
	 esac
	 ;;
      2) print "\
For completers which correct what you have typed, you sometimes want
to keep the original string instead, so if the correction was ambiguous
the original string is always listed as a possible completion.  However,
if there was just one completion it is usually accepted.  You can
force completion to offer the original string as a possibility even in
this case.  Do you want this?
"
         while true; do
	   read -k key'?[y]es, [n]o, [k]eep old setting? '
	   print
	   [[ $key = [yYnNkK] ]] && break
	 done
	 case $key in
	   [yY]) original=true
	         ;;
           [nN]) original=false
	         ;;
	 esac
	 ;;
      [qQ]) return 1
	      ;;
    esac

  done

  __ci_set_this_style insert-unambiguous insertu
  __ci_set_this_style original original
  # __ci_set_this_style sort sort

  return 0;
}


__ci_do_selection() {
  local key listc menu select amenu elt listp selectp haslistp hasselectp
  integer num

  __ci_get_this_style list-colors listc
  __ci_get_this_style menu menu
  __ci_get_this_style list-prompt listp
  [[ -n $listp ]] && haslistp=1
  listp=${(Q)listp}
  __ci_get_this_style select-prompt selectp
  [[ -n $selectp ]] && hasselectp=1
  selectp=${(Q)selectp}

  while true; do
    clear
    print "\
     *** compinstall: options for colouring and selecting in lists ***

1.   Use coloured lists for listing completions.

2.   Use cursor keys to select completions from completion lists.

3.   Allow scrolling of long selection lists and set the prompt.

q.   Return without saving.
0.   Done setting options for insertion.
"
    read -k key'?--- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      1) print "\
Zsh can produce coloured completion listings where different file types
etc. appear in different colours.  If you want to tailor that to your
own needs, you will have to edit ~/.zshrc.  Here you have the choice of:

1.  Using the default colours.
2.  Using the colours already set up for GNU ls via the \$LS_COLORS
    environment variable.  Note this must be set before the completion
    configuration code is executed.
3.  Turn colouring off.
0.  Leave the setting the way it is.  Choose this if you have a custom
    setting and you don't want to lose it.
"
         while true; do
	   read -k key'?Enter 1, 2, 3, 0: '
	   print
	   [[ $key = [1230] ]] && break
	 done
	 case $key in
	   1) listc="''"
	      ;;
	   2) listc='${(s.:.)LS_COLORS}'
	      ;;
	   3) listc=
	      ;;
	 esac
	 ;;
      2) print "\
If you use zsh's menu completion and the feature that all short completion
lists appear below the line on which you are editing, you can enable
\`menu selection', which lets you pick a completion with the cursor keys:
the choice is highlighted, and hitting return accepts it.  Note that
this only happens when you are already using menu completion.  This
feature can be set so that it is only enabled when there are a certain
number of completions.  Please enter:

- 0 or 1, to turn this feature on unconditionally
- a higher number to turn this feature on when there are that many
  completions
- an \`l' for \`long' to turn it on for listings which don't fit on the
  screen.
- an \`ll' for \`long list' to turn it on for completions which don't fit
  on the screen, even for commands which only do listing of completions.
  This may be combined with a number which will be used in ordinary selection.
- a negative number to turn this feature off
- an empty line to leave the setting the way it is.
"
	 # Better to parse and display the current setting.
         while true; do
           vared -eh -p 'value> ' select
	   [[ -z $select || $select = ((-|)<->|l|<->#ll<->#) ]] && break;
	   print "Type a number, l, ll, ll<num>, or an empty line." >&2
	 done
	 amenu=(${=menu})
	 elt=${amenu[(i)*select*]}
	 [[ $elt -eq 0 || $elt -gt $#amenu ]] && elt=
	 case $select in
	   <->) if [[ -n $elt ]]; then
		  amenu[$elt]="select=$select"
		else
		  amenu=($amenu "select=$select")
	        fi
		menu="$amenu"
		;;
	   *ll*) num=${(RS)select##ll}
	         select="select=long-list"
		 [[ -n $num ]] && select="$select select=$num"
		 if [[ -n $elt ]]; then
		   amenu[$elt]=$select
		 else
		   amenu=($amenu $select)
		 fi
		 menu="$amenu"
		 ;;
	   l#) if [[ -n $elt ]]; then
                 amenu[$elt]="select=long"
               else
                 amenu=($amenu "select=long")
               fi
	       menu="$amenu"
               ;;
	   -<->) if [[ -n $elt ]]; then
		    # i never liked the way indexing was done anyway
		    if [[ $elt -eq 1 ]]; then
		      amenu=($amenu[$elt+1,-1])
		    else
		      amenu=($amenu[1,$elt-1] $amenu[$elt+1,-1])
		    fi
		 fi
		 menu="$amenu"
		 ;;
	 esac
	 if [[ $menu = *select* ]]; then
	   print "\
You can also set a prompt to use for menu selection when it would scroll
off the screen.  Unless this is set, you won't see a prompt, but the feature
is still enabled.

Edit a prompt below.  It can contain \`%l' to show the number of matches
as \`current_number/total_number', \`%p' to show the fraction of
the way down the list, or font-control sequences such as %B, %U, %S and
the corresponding %b, %u, %s; quotes will be added automatically.  Delete
the whole line to turn it off.  Hit return to keep the current value.
"
	   [[ -z $hasselectp ]] &&
	     selectp='%SScrolling active: current selection at %p%s'
	   vared -eh -p 'prompt> ' -c selectp
	   [[ -z $selectp ]] && hasselectp=
	 fi
         ;;
      3) print "\
You can make completion lists scroll when they don't fit on the screen.
Note this is different from scrolling in menu selection --- a more basic
pager is used which should work even with fairly stupid terminals.

To enable this, edit a prompt to show when scrolling is active; an empty 
string turns this feature off.  It can contain \`%l' to show the number of
matches as \`current_number/total_number', \`%p' to show the fraction of
the way down the list, or font-control sequences such as %B, %U, %S and the
corresponding %b, %u, %s; quotes will be added automatically.  Delete the
whole line to turn this behaviour off, in which case the display of
completions which don't fit on the screen is controlled by the LISTMAX
parameter (currently ${LISTMAX:-unset}), which specifies the maximum number
to show without asking.  Hit return to keep the current value.
"
         [[ -z $haslistp ]] &&
	   listp='%SAt %p: Hit TAB for more, or the character to insert%s'
	 vared -eh -p 'prompt> ' -c listp
	 [[ -z $listp ]] && haslistp=
	 ;;
      q) return 1
         ;;
    esac
  done

  __ci_set_this_style list-colors listc
  __ci_set_this_style menu menu
  [[ -n $haslistp ]] && listp=${(qq)listp}
  __ci_set_this_style list-prompt listp
  [[ -n $hasselectp ]] && selectp=${(qq)selectp}
  __ci_set_this_style select-prompt selectp

  return 0
}


__ci_do_display() {
  local key usec

  __ci_get_this_style use-compctl usec

  while true; do
    clear
    print "\
         *** compinstall: display and insertion options ***

1.  Change appearance of completion lists:  allows descriptions of
    completions to appear and sorting of different types of completions.

2.  Change how completions are inserted: includes options for sorting,
    and keeping the original or an unambiguous prefix with correction etc.

3.  Configure coloured/highlighted completion lists, selection of items
    and scrolling.

4.  Change whether old-style \`compctl' completions will be used.

q.  Return without saving.
0.  Done setting display and insertion options.
"

    read -k key'?--- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      1) __ci_do_list_format
	 ;;
      2) __ci_do_insertion
	 ;;
      3)  __ci_do_selection
	 ;;
      4) print "\
Completions defined by the new completion system (the one you are
configuring) always take precedence over the old sort defined with compctl.
You can choose whether or not you want to search for a compctl-defined
completion if no new completion was found for a command.  The default
behaviour is only to check for compctl-defined completions if the required
library, zsh/compctl, is already loaded.  (If not, this implies that
compctl has not been called.)  Do you want to test for compctl-defined
completions?
"
         while true; do
	   read -k key'?[y]es, [n]o, if [l]oaded, [k]eep old setting? '
	   print
	   [[ $key = [yYnNlLkK] ]] && break
	 done
	 case $key in
	   [yY]) usec=true
	         ;;
	   [nN]) usec=false
	         ;;
	   [lL]) usec=
	         ;;
	 esac
	 ;;
      q) return 1
	 ;;
    esac

  done

  __ci_set_this_style use-compctl usec

  return 0
}


#       file-sort, special-dirs, ignore-parents,
#       squeeze-slashes,
__ci_do_file_styles() {
  local key files cursor expand speciald ignorep squeezes select
  local prefon suffon lssuffixes preserve

  __ci_get_this_style file-sort files
  __ci_get_this_style ignore-parents ignorep
  __ci_get_this_style special-dirs speciald
  __ci_get_this_style squeeze-slashes squeezes
  __ci_get_this_style expand expand
  __ci_get_this_style list-suffixes lssuffixes
  __ci_get_this_style preserve-prefix preserve
  [[ -n $preserve ]] && preserve=${(Q)preserve}

  while true; do
    clear
    print "\
      *** compinstall: options for filename completion ***

1.  Choose how to sort the displayed list of filename matches.

2.  In expressions with .., don't include directories already implied.

3.  Allow completion of . and .. for the bone idle.

4.  When expanding paths, \`foo//bar' is treated as \`foo/bar'.

5.  Configure how multiple paths are expanded and displayed, 
    e.g. /f/b -> /foo/bar

6.  Keep certain prefixes unchanged, such as \`//resource/'.

q.  Return without saving.
0.  Done setting options for filename completion.
"
    read -k key'?--- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      (1) print "\
Filenames listed as possible completions are usually displayed in
alphabetical order.  You can alternatively choose:
  s  File size
  l  Number of (hard) links
  m  Modification time
  a  Access time
  i  Inode change time
  n  File name
  k  Keep the current setting
You can also specify the reverse of any of the above orders (except \`k'):  to
do this, type the appropriate letter in upper case.
"
         while true; do
           read -k key'?--- Hit selection --- '
	   print
	   [[ $key = [sSlLmMaAiInNkK] ]] && break
	 done
	 case $key in
	   ([sS]) files=size;;
	   ([lL]) files=links;;
	   ([mM]) files=modification;;
	   ([aA]) files=access;;
	   ([iI]) files=inode;;
	   ([nN]) files=name;;
	 esac
	 if [[ $key = [SLAMIN] ]]; then
	   # slam it into reverse
	   files="$files reverse"
	 fi
	 ;;
      (2) print "\
When you type an expression containing \`..', you may usually not want to
be offered certain directories for completion.
  p   Don't offer parents:  in \`foo/bar/../', don't make \`bar' a completion.
  c   Don't offer the current directory, e.g. after \`../'.
  o   Only perform the two tests if there is a real \`..' in the word so far.
  d   Only perform the two tests when completing directory names.
  0   None of the above; use normal completion.
  k   Keep the current settings.
You may specify any combination of p, c, o, d including at least one of p
and c, or you may specify either 0 or k.  Note that the _ignored completer
functions in the normal way, i.e. you would be able to complete the
directories in question if nothing else matched.
"
          while true; do
	    vared -eh -p 'selection> ' select
	    [[ ( $select = [pPcCoOdD]# && $select = *[pPcC]* )
		    || $select = [0kK] ]] && break
	    print "Type any combination of p, c, o, d, or type 0 or k"
	  done
	  case $select in
	    (0) ignorep=
		;;
	    ([pPcCoOdD]#)
		ignorep=()
		[[ $select = *[pP]* ]] && ignorep=($ignorep parent)
		[[ $select = *[cC]* ]] && ignorep=($ignorep pwd)
		[[ $select = *[oO]* ]] && ignorep=($ignorep ..)
		[[ $select = *[dD]* ]] && ignorep=($ignorep directory)
		;;
	  esac
	  ;;
      (3) print "\
Filename completion does not usually offer the directory names \`.' and
\`..' as choices.  However, some immensely lazy people can't even be
bothered to type these.  Do you wish to be offered \`.' and \`..' as
choices ([y]es, [n]o, [k]eep current setting)?
"
          while true; do
            read -k key'?--- Hit selection --- '
	    [[ $key = [yYnNkK] ]] && break
	    print "Type y, n or k."
	  done
	  case $key in
	    ([yY]) speciald=true;;
	    ([nN]) speciald=;;
	  esac
	  ;;
      (4) print "\
Filename completion can complete sets of path segments at once, for example
\`/u/X/l/X' to \`/usr/X11R6/lib/X11'.  Normally this means that multiple
slashes in filenames are treated as matching multiple directories.  For
example, \`foo//bar' could expand to \`foo/datthe/bar'.  You can, however,
stick to the usual UNIX convention that multiple slashes are treated as
a single slash.  Do you wish to treat multiple slashes the same as just
one ([y]es, [n]o, [k]eep current setting)?
"
          while true; do
	    read -k key'?--- Hit selection --- '
	    [[ $key = [yYnNkK] ]] && break
	    print "Type one of y, n or k."
	  done
	  case $key in
	    ([yY]) squeezes=true;;
	    ([nN]) squeezes=;;
	  esac
          ;;
      (5) if [[ $expand = *prefix* ]]; then
             prefon=prefix
	  else
	     prefon=
	  fi
	  if [[ $expand = *suffix* ]]; then
	     suffon=suffix
	  else
	     suffon=
	  fi
          print "
When expanding /f/b, the shell will attempt to match /f*/b* (e.g. /foo/bar), 
and so on to any depth.  If the first part of the expansion fails, by default
the shell will not expand the remainder.  However, you can force it always
to expand the first part.  Currently this feature is ${${prefon:+on}:-off}.
Do you want it on ([y]es, [n]o, [k]eep current setting)?
"
	  while true; do
	    read -k key'?--- Hit selection --- '
	    [[ $key = [yYnNkK] ]] && break
	    print "Type one of y, n or k."
	  done
	  case $key in
	    ([yY]) prefon=prefix;;
	    ([nN]) prefon=prefix;;
	  esac
	  print "
Further, if /f*/b* is ambiguous, the shell will usually only expand
as far as the part that is unambiguous; for example, if /foo/bar and
/food/basket exist, it will wait for you to choose either /foo or /food,
and not attempt to expand the rest of the match.  However, you can force
it to add all possible completions for you to resolve conflicts in the
normal way.  Currently this feature is ${${suffon:+on}:-off}.
Do you want it on ([y]es, [n]o, [k]eep current setting)?
"
	  while true; do
	    read -k key'?--- Hit selection --- '
	    [[ $key = [yYnNkK] ]] && break
	    print "Type one of y, n or k."
	  done
	  case $key in
	    ([yY]) suffon=suffix;;
	    ([nN]) suffon=suffix;;
	  esac
	  expand=${prefon:+$prefon${suffon:+ }}${suffon}

	  if [[ $lssuffixes = (1|[tT]|[yY]|[oO])* ]]; then
	     lssuffixes=true
	  else
	     lssuffixes=
	  fi
	  print "
When listing expansions of /f/b such as /foo/bar, /foo/bad, /failed/bag,
the shell will usually only show the first part of the path if it is
ambiguous, hence /foo will appear twice.  It is possible to show the
full path in this case.  Currently this feature is ${${lssuffixes:+on}:-off}.
Do you want this behaviour ([y]es, [n]o, [k]eep current setting)?
"
	  while true; do
	    read -k key'?--- Hit selection --- '
	    [[ $key = [yYnNkK] ]] && break
	    print "Type one of y, n or k."
	  done
	  case $key in
	    ([yY]) lssuffixes=true;;
	    ([nN]) lssuffixes=;;
	  esac
	  ;;
      (6) print "\
On some systems, there are special forms for the start of a filename
which should be left alone by the completion system.  For example, Cygwin
uses a double slash to indicate a network resource, hence a prefix of
the form \`//resource/' should be left alone.  This style gives a pattern
to match any such prefixes; alternatives separated by \`|' are therefore
possible.  Edit the pattern as you like.  If this is empty, the shell will not
handle any prefixes specially."
          if [[ -z $preserve ]]; then
	      preserve="//[^/]##/"
	      print "
Accept the default to handle network resources as just described."
	  fi
	  vared -eh -p "pattern> " preserve
	  ;;
      (q) return 1
	 ;;
    esac

  done

  __ci_set_this_style file-sort files
  __ci_set_this_style ignore-parents ignorep
  __ci_set_this_style special-dirs speciald
  __ci_set_this_style squeeze-slashes squeezes
  __ci_set_this_style expand expand
  __ci_set_this_style list-suffixes lssuffixes
  # pattern, always quote
  [[ -n $preserve ]] && preserve=${(qq)preserve}
  __ci_set_this_style preserve-prefix preserve

  return 0
}


# TODO: history completion, jobs, prefix-needed 'n' stuff.
__ci_do_misc() {
  local key

  while true; do
    clear
    print "\
      *** compinstall: options for particular types of completion ***

1.  Options for file completion.

q.  Return without saving.
0.  Done setting options for particular completions.
"
    read -k key'?--- Hit selection --- '
    print

    [[ $key = 0 ]] && break

    case $key in
      1) __ci_do_file_styles
	 ;;
      q) return 1
	 ;;
    esac

  done

  return 0;
}


# TODO: it should probably be possible to set completion options via
#         compinstall, even though they've been around for years.

while true; do
  clear
  print "\
               *** compinstall: main menu ***
Note that hitting \`q' in menus does not abort the set of changes from
lower level menus.  However, quitting at top level will ensure that nothing
at all is actually written out.

1.  Completers:  choose completion behaviour for tasks such as
    approximation, spell-checking, expansion.

2.  Matching control: set behaviour for case-insensitive matching,
    extended (partial-word) matching and substring matching.

3.  Styles for changing the way completions are displayed and inserted.

4.  Styles for particular completions.

c.  Change context (plus more information on contexts).

q.  Return without saving.
0.  Save and exit.
"

  __ci_newline \
    "--- Hit choice --- " || return 1

  # note this is a string test:  we require the `0' to have been typed.
  [[ $key = 0 ]] && break

  case $key in
    1) __ci_do_completers
       ;;
    2) __ci_do_matchers
       ;;
    3) __ci_do_display
       ;;
    4) __ci_do_misc
       ;;
    c) __ci_change_context
       ;;
  esac
done


if (( $#styles )); then
  typeset style stylevals context values
  for style in ${(ko)styles}; do
    stylevals=(${(f)styles[$style]})
    while (( $#stylevals )); do
      output="$output
zstyle ${(qq)stylevals[1]} $style ${stylevals[2]}"
      shift 2 stylevals
    done
  done
fi

if [[ -z $ifile || -d $ifile ]] ||
  ! read -q key"?Save new settings to $ifile ([y]es, [n]o)? "; then
   print "Enter file to save in (~ will be expanded), or return to abort:"
   ifile=
   vared -ch -p 'file> ' ifile
   if [[ $ifile != [/~]* ]]; then
     ifile=$PWD/$ifile
     print "[Not absolute path; updating to $ifile]"
   fi
   ifile=${~ifile}
fi

local tmpout=${TMPPREFIX:-/tmp/zsh}compinstall$$
#
# Assemble the complete set of lines to
# insert.
#
__ci_output >$tmpout

if [[ -n $ifile ]]; then
  if [[ $ifile != *(zshrc|zlogin|zshenv) ]]; then 
    print "\
If you want this file to be run automatically, you should add
  . $ifile
to your .zshrc.  compinstall will remember the name of this file for
future use."
    __ci_newline || return 1
  fi
  #
  # Now use sed to update the file.
  #
  if [[ -f $ifile ]]; then
    cp $ifile ${ifile}\~ &&
    print "Copied old file to ${ifile}~."
  else
    touch $ifile
  fi
  if { { grep "$endline" $ifile >/dev/null 2>&1 &&
         sed -e "/^[ 	]*$endline/r $tmpout
/^[ 	]*$startline/,/^[ 	]*$endline/d" $ifile >${tmpout}2 } || 
        { cp $ifile ${tmpout}2 && cat $tmpout >>${tmpout}2 } } &&
  cp ${tmpout}2 $ifile && rm -f ${tmpout}2; then
    print "\nSuccessfully added compinstall lines to $ifile."
    rm -f $tmpout
  else
    print "\nFailure adding lines to $ifile.  Lines left in \`$tmpout'"
  fi
  rm -f ${tmpout}2
elif read -q key'?Print them to stdout instead ([y]es, [n]o)? '; then
  cat $tmpout
  rm -f $tmpout
fi

if read -q key'?Set new styles for immediate use ([y]es, [n]o)? '; then
  eval $output
  print "The new settings are now in effect.  Note this will not remove old
styles you have deleted until you restart the shell."
fi

__ci_tidyup
return 0