# TeXLive::TLWinGoo.pm
# Windows nastiness
#
# Copyright 2008 Siep Kroonenberg, Norbert Preining
# This file is licensed under the GNU General Public License version 2
# or any later version.

# code for broadcast_env adopted from Win32::Env:
# Copyright 2006 Oleg "Rowaa[SR13]" V. Volkov, all rights reserved.
# This program is free software; you can redistribute it and/or modify it
# under the same terms as Perl itself.

package TeXLive::TLWinGoo;

=pod

=head1 NAME

C<TeXLive::TLWinGoo> -- Additional utilities for Windows

=head2 SYNOPSIS

  use TeXLive::TLWinGoo;

=head2 ERROR HANDLING

  TeXLive::TLWinGoo::wg_error;

=head2 DIAGNOSTICS

  TeXLive::TLWinGoo::win_version;
  TeXLive::TLWinGoo::is_vista;
  TeXLive::TLWinGoo::admin;
  TeXLive::TLWinGoo::non_admin;
  TeXLive::TLWinGoo::reg_country;
  TeXLive::TLWinGoo::dir_writable($d);

=head2 ENVIRONMENT AND REGISTRY

  TeXLive::TLWinGoo::expand_string($s);
  TeXLive::TLWinGoo::global_tmpdir;
  TeXLive::TLWinGoo::get_system_path;
  TeXLive::TLWinGoo::get_user_path;
  TeXLive::TLWinGoo::setenv_reg($env_var, $env_data);
  TeXLive::TLWinGoo::unsetenv_reg($env_var);
  TeXLive::TLWinGoo::add_texbindir_to_path($texpath);
  TeXLive::TLWinGoo::remove_texbindirs_from_path;
  TeXLive::TLWinGoo::register_script_type($extension, $command);
  TeXLive::TLWinGoo::unregister_script_type($extension);
  TeXLive::TLWinGoo::create_uninstaller;
  TeXLive::TLWinGoo::unregister_uninstaller;

=head2 ACTIVATING CHANGES IMMEDIATELY

  TeXLive::TLWinGoo::broadcast_env;
  TeXLive::TLWinGoo::update_assocs;

All exported functions return forward slashes.

=head2 DESCRIPTION

=over 6

=cut

BEGIN {
  use Exporter;
  use vars qw( @ISA @EXPORT $Registry);
  @ISA = qw( Exporter );
  @EXPORT = qw(
    &wg_error
    &win_version
    &is_vista
    &admin
    &non_admin
    &reg_country
    &dir_writable
    &expand_string
    &global_tmpdir
    &get_system_path
    &get_user_path
    &setenv_reg
    &unsetenv_reg
    &add_texbindir_to_path
    &remove_texbindirs_from_path
    &register_script_type
    &unregister_script_type
    &broadcast_env
    &update_assocs
    &create_uninstaller
    &unregister_uninstaller
  );
  # for testing also:
  @EXPORT_OK = qw(
    &admin_again
    &get_system_env
    &get_user_env
    &win_which_dir
    &global_tmpdir
  );
  if ($^O=~/^MSWin(32|64)$/i) {
    #require Win32;
    #Win32->import( qw( GetOSVersion ) );
    require Win32::API;
    require Win32::TieRegistry;
    Win32::TieRegistry->import( qw( $Registry
      REG_SZ REG_EXPAND_SZ  KEY_READ KEY_WRITE KEY_ALL_ACCESS
         KEY_ENUMERATE_SUB_KEYS ) );
    $Registry->Delimiter('/');
    $Registry->ArrayValues(0);
    $Registry->FixSzNulls(1);
  }
}

use TeXLive::TLUtils;

my $is_win = $^O=~/^MSWin(32|64)$/i;

=pod

=back

=head2 ERROR HANDLING

=over 6

=item C<wg_error>

Returns WinGoo error status, in the shape of an array (number,
message) and clears the error status. No error <=> error number 0

=cut

my $wg_error = 0;
my $wg_error_message = "";

sub wg_error {
  my @retval = ($wg_error, $wg_error_message);
  $wg_error = 0;
  $wg_error_message = "";
  return @retval;
}

=pod

=back

=head2 DIAGNOSTICS

=over 6

=item C<win_version>

C<win_version> returns the Windows version number as stored in the
registry: 5.0 for Windows 2000, 5.1 for Windows XP and 6.0 for Vista.

=cut

my $windows_version = 0;

if ($is_win) {
  my $tempkey = $Registry->Open(
    "LMachine/software/Microsoft/Windows NT/CurrentVersion/",
    {Access => KEY_READ() });
  $windows_version = $tempkey -> { "/CurrentVersion" };
}

sub win_version { return $windows_version; }

=item C<is_vista>

C<is_vista> returns 1 if win_version is >= 6.0, otherwise 0.

=cut

sub is_vista { return $windows_version >= 6; }

# permissions with which we try to access the system environment

my $is_admin = 1;

sub sys_access_permissions {
  $is_admin ? KEY_ALL_ACCESS() : KEY_READ() | KEY_ENUMERATE_SUB_KEYS();
}

sub get_system_env {
  return $Registry -> Open(
    "LMachine/system/currentcontrolset/control/session manager/Environment/",
    {Access => sys_access_permissions()});
}

# $is_admin was set to true originally. With this value,
# sys-access_permissions returns full access permissions. If that
# doesn't work out then apparently we aren't administrator, so we
# set $is_admin to 0.

if ($is_win) {
  $is_admin = 0 if not get_system_env();
}

sub get_user_env {
  return $Registry -> Open("CUser/Environment", {Access => KEY_ALL_ACCESS()});
}

=pod

=item C<admin>

Returns admin status, admin implying having full read-write access
to the system environment.

=cut

sub admin { return $is_admin; }

=pod

=item C<non_admin>

Pretend not to have admin privileges, to enforce a user- rather than
a system install.

Currently only used for testing.

=cut

sub non_admin { $is_admin = 0; }

# just for testing; doesn't check actual user permissions
sub admin_again { $is_admin = 1; }

=pod

=item C<reg_country>

Two-letter country code representing the locale of the current user

=cut

sub reg_country {
  my $value = $Registry -> {"CUser/Control Panel/International//Locale"};
  $value = substr $value, -4;
  my $lm = $Registry -> Open("HKEY_CLASSES_ROOT/MIME/Database/Rfc1766/",
                             {Access => KEY_READ()})->{"/$value"};
  tllog($::LOG_DEBUG, "found lang codes value = $value, lm = $lm...\n");
  if ($lm) {
    return(substr $lm, 0, 2);
  }
}

=pod

=item C<dir_writable($d)>

Tests whether its argument is writable by trying to write to
it. This function is necessary because the built-in C<-w> test
apparently doesn't work under Windows.

=cut

sub dir_writable {
  $d=shift;
  return 0 unless -d $d;
  $d =~ s!\\!/!g;
  $d =~ s!/$!!g;
  my $i = 0;
  while (-e $d . "/" . $i) { $i++; }
  my $f = $d."/".$i;
  my $fb = $f;
  $fb =~ s!/!\\!g;
  return 0 if
    system('copy /b ' . $ENV{'COMSPEC'} . ' "' . $fb . '" >nul 2>&1');
  unlink $f if -e $f;
  return 1;
}

=pod

=back

=head2 ENVIRONMENT AND REGISTRY

=over 6

Most settings can be made for a user and for the system. User
settings override system settings.

For admin users, the functions below affect both user- and system
settings. For non-admin users, only user settings are changed.

An exception is the search path: the effective searchpath consists
of the system searchpath in front concatenated with the user
searchpath at the back.

Note that in a roaming profile network setup, users take only user
settings with them to other systems, not system settings. In this
case, with a TeXLive on the network, a nonadmin install makes the
most sense.

=item C<expand_string($s)>

This function replaces substrings C<%env_var%> with their current
values as environment variable and returns the result.

=cut

sub expand_string {
  $s = shift @_;
  while ($s =~ /^([^%]*)%([^%]+)%(.*)$/) {
    foreach $k (keys %ENV) {
      if (uc($k) eq uc($2)) {
        $s = $1 . $ENV{$k} . $3;
        last;
      }
    }
  }
  $s;
}

=pod

=item C<global_tmpdir>

Returns the expanded value of C<%TEMP%> from the system environment,
usually C<%SystemRoot%/Temp>. This value is normally not available
from C<%ENV>.

=cut

if ($is_win) {
  $global_tmp = expand_string(get_system_env()->{'TEMP'}) if $is_win;
}

my $global_tmp = "/tmp";

sub global_tmpdir { return $global_tmp; }

sub is_a_texdir {
  my $d = shift;
  #my $xd = expand_string($d);
  $d =~ s/\\/\//g;
  $d =~ s/\/$//;
  my $d1 = $d . '/pdftex.exe';
  my $d2 = $d . '/tex.exe';
  return ((-e $d1) or (-e $d2));
}

=pod

=item C<get_system_path>

Returns unexpanded system path, as stored in the registry, but with
forward slashes.

=cut

sub get_system_path {
  my $value = get_system_env() -> {'/Path'};
  $value =~ s/\\/\//g;
  # Remove terminating zero bytes; there may be several, at least
  # under w2k, and the FixSzNulls option only removes one.
  $value =~ s/[\s\x00]+$//;
  return $value;
}

=pod

=item C<get_user_path>

Returns unexpanded user path, as stored in the registry, but with
forward slashes. The user path often does not exist, and is rarely
expandable.

=cut

sub get_user_path {
  my $value = get_user_env() -> {'/Path'};
  return "" if not $value;
  $value =~ s/\\/\//g;
  $value =~ s/[\s\x00]+$//;
  return $value;
}

#=pod
#
#=item C<win_which_dir>
#
#More or less the same as which, except that 1. it returns a
#directory, 2. it consults the path stored in the registry rather
#than the path of the current process, and 3. it assumes that the
#filename includes an extension. Currently only used for testing.
#
#=cut

sub win_which_dir {
  my $prog = shift;
  my $d;
  # first check system path
  my $path = expand_string(get_system_path());
  my $user_path = expand_string(get_user_path());
  $path = $path . ';' . $user_path if $user_path;
  foreach $d (split (';',$path)) {
    $d =~ s/\/$//;
    return $d if -e $d.'/'.$prog;
  }
  return 0;
}

=pod

=item C<setenv_reg($env_var, $env_data[, $mode]);>

Set an environment variable $env_var to $env_data.

$mode="user": set for current user. $mode="system": set for all
users. Default: both if admin, current user otherwise.

=cut

sub setenv_reg {
  my $env_var = shift;
  my $env_data = shift;
  my $mode = @_ ? shift : "default";
  die "setenv_reg: Invalid mode"
    if ($mode ne "user" and $mode ne "system" and $mode ne "default");
  die "setenv_reg: mode 'system' only available for admin"
    if ($mode eq "system" and !$is_admin);
  my $env;
  if ($mode ne "system") {
    my $env = get_user_env();
    $env->ArrayValues(1);
    $env->{'/'.$env_var} =
       [ $env_data, ($env_data =~ /%/) ? REG_EXPAND_SZ : REG_SZ ];
  }
  if ($mode ne "user" and $is_admin) {
    $env = get_system_env();
    $env->ArrayValues(1);
    $env->{'/'.$env_var} =
       [ $env_data, ($env_data =~ /%/) ? REG_EXPAND_SZ : REG_SZ ];
  }
}

=pod

=item C<unsetenv_reg($env_var[, $mode]);>

Unset an environment variable $env_var

=cut

sub unsetenv_reg {
  my $env_var = shift;
  my $env = get_user_env();
  my $mode = @_ ? shift : "default";
  #print "Unsetenv_reg: unset $env_var with mode $mode\n";
  die "unsetenv_reg: Invalid mode"
    if ($mode ne "user" and $mode ne "system" and $mode ne "default");
  die "unsetenv_reg: mode 'system' only available for admin"
    if ($mode eq "system" and !$is_admin);
  delete get_user_env()->{'/'.$env_var} if $mode ne "system";
  delete get_system_env()->{'/'.$env_var} if ($mode ne "user" and $is_admin);
}

=pod

=item C<add_texbindir_to_path($texpath)>

Remove wrong TeX directories from system path (if possible) and user
path. A directory is a TeX directory if it contains tex.exe or
pdftex.exe.  Then if necessary add desired TeX directory; to system path if
admin, otherwise to user path. wg_error gets set if there is a
connflicting tex directory which cannot be removed from the path.

=cut

sub add_texbindir_to_path {
  $wg_error = 0; # clear error status
  my $texbindir = shift;

  my $system_env = get_system_env();
  my $user_env = get_user_env();
  my $d;
  my $d_exp;
  my $found = 0;
  my @newpt;
  my $newp;

  # system path
  if ($is_admin) {
    @newpt = ();
    foreach $d (split (';', get_system_path())) {
      $d_exp = expand_string($d);
      $d_exp =~ s/\\/\//g;
      $d_exp =~ s/\/$//;
      if (uc($d_exp) eq uc($texbindir)) {
        push @newpt, $d unless $found;
        $found = 1;
      } elsif (!is_a_texdir($d_exp)) {
        push @newpt, $d;
      }
    }
    push @newpt, $texbindir unless $found;
    $found = 1;
    $newp = join (';', @newpt);
    $newp =~ s/\//\\/g;
    setenv_reg("Path", $newp, "system");
    #$system_env->ArrayValues(1); # use value_data, value_type pairs
    #$system_env -> {"/Path"} = [ $newp, REG_EXPAND_SZ ];
  } else { # non-admin
    # system path
    foreach $d (split (';', get_system_path())) {
      $d_exp = expand_string($d);
      $d_exp =~ s/\\/\//g;
      $d_exp =~ s/\/$//;
      if (uc($d_exp) eq uc($texbindir)) {
        $found = 1;
      } elsif (is_a_texdir($d_exp)) {
        $wg_error = 1;
        $wg_error_message =
          "Warning: possibly conflicting [pdf]TeX program found at $d_exp\n";
        tllog($::LOG_DEBUG, $wg_error_message);
      }
    }
  }

  # user path
  @newpt = ();
  foreach $d (split (';', get_user_path())) {
    $d_exp = expand_string($d);
    $d_exp =~ s/\\/\//g;
    $d_exp =~ s/\/$//;
    if (uc($d_exp) eq uc($texbindir)) {
      push @newpt, $d unless $found; # admin case: always $found
      $found = 1;
    } elsif (!is_a_texdir($d_exp)) {
      push @newpt, $d;
    }
  }
  push @newpt, $texbindir unless $found;
  if (@newpt) {
    $newp = join ';', @newpt;
    $newp =~ s/\//\\/g;
    $user_env->ArrayValues(1); # use value_data, value_type pairs
    #$user_env -> {"/Path"} = [ $newp,
    #  ($newp =~ /%/) ? REG_EXPAND_SZ : REG_SZ ];
    setenv_reg("Path", $newp, "user");
  } else {
    unsetenv_reg("PAth", "user");
  }
}

=pod

=item C<remove_texbindirs_from_path>

Remove all directories from the searchpath which contain tex.exe or
pdftex.exe. Do this with the user path and if admin also with the
system path.

=cut

sub remove_texbindirs_from_path {
  $wg_error = 0; # clear error status

  my $system_env = get_system_env();
  my $user_env = get_user_env();
  my ($d, $d_exp, @newpt, $newp);

  # system path
  if ($is_admin) {
    @newpt = ();
    foreach $d (split (';', get_system_path())) {
      $d_exp = expand_string($d);
      $d_exp =~ s/\\/\//g;
      $d_exp =~ s/\/$//;
      push @newpt, $d unless is_a_texdir($d_exp);
    }
    $newp = join (';', @newpt);
    $newp =~ s/\//\\/g;
    setenv_reg("Path", $newp, "system");
  }

  # user path
  @newpt = ();
  foreach $d (split (';', get_user_path())) {
    $d_exp = expand_string($d);
    $d_exp =~ s/\\/\//g;
    $d_exp =~ s/\/$//;
    push @newpt, $d unless is_a_texdir($d_exp);
  }
  if (@newpt) {
    $newp = join(';', @newpt);
    $newp =~ s/\//\\/g;
    setenv_reg("Path", $newp, "user");
  } else {
    unsetenv_reg("Path", "user");
  }
}

# delete a registry key recursively.
# the key parameter should be a string, not a registry object.
# We shall use this with file types.

sub reg_delete_recurse {
  my $parent = shift;
  my $childname = shift;
  tllog ($::LOG_DDDEBUG, "Deleting $childname regkey\n");
  if ($childname !~ '^/') { # subkey
    my $child = $parent->Open ($childname, {Access => KEY_ALL_ACCESS()});
    return unless $child;
    foreach my $v (keys %$child) {
      if ($v =~ '^/') { # value
        delete $child->{$v};
      } else { # subkey
        reg_delete_recurse ($child, $v);
      }
    }
    delete $child->{'/'};
  }
  delete $parent->{$childname};
}

=pod

=pod

=item C<register_script_type($extension, $command)>

Add registry entries to associate $extension with $command and make
$extension an executable file type. Slashes are flipped where necessary.

=cut

sub register_script_type {
  my $extension = shift;
  $extension = '.'.$extension unless $extension =~ /^\./; # ensure leading dot
  $extension = uc($extension);
  my $command = shift;
  $command =~s/\//\\/g;
  tllog ($::LOG_DDEBUG, "Linking $extension to $command\n");
  my $user_env = get_user_env();
  my $system_env = get_system_env();
  my ($pathext, $found, $e, $classes_key, $k);

  # pathext
  if (!$::opt_portable) {
    if ($is_admin) {
      # system pathext
      $pathext = $system_env -> {'/PATHEXT'};
      $found = 0;
      foreach $e (split(/;/,$pathext)) {
        $found = 1 if (uc($e) eq $extension);
      }
      setenv_reg("PATHEXT", $pathext.";".$extension, "system") unless $found;
      # user pathext
      $pathext = $user_env -> {'/PATHEXT'};
      if ($pathext) {
        $found = 0;
        foreach $e (split(/;/,$pathext)) {
          $found = 1 if (uc($e) eq $extension);
        }
        setenv_reg("PATHEXT", $pathext.";".$extension, "user") unless $found;
      }
    } else { # non-admin
      $pathext = $user_env -> {'/PATHEXT'};
      $pathext = $system_env -> {'/PATHEXT'} if not $pathext;
      $found = 0;
      foreach $e (split(/;/,$pathext)) {
        $found = 1 if (uc($e) eq $extension);
      }
      setenv_reg("PATHEXT", $pathext.";".$extension, "user") unless $found;
    }
  }

  # file type
  $extension = lc($extension);
  if ($is_admin) {
    $classes_key = $Registry -> Open("LMachine/Software/Classes/",
      {Access => KEY_ALL_ACCESS()}) or die "Cannot open classpath";
    $k = $classes_key->CreateKey($extension);
    $k -> ArrayValues(0);
    $k -> {"/"} = "script".$extension;
    $k = $classes_key->CreateKey("script".$extension."/Shell/Open/Command/");
    $k -> ArrayValues(1);
    $k -> {"/"} = [ '"'.$command.'" "%1" %*',
      ($command =~ /%/) ? REG_EXPAND_SZ : REG_SZ ];
    # delete possibly conflicting values from HKCU/software
    $classes_key = $Registry -> Open("CUser/Software/Classes/",
        {Access => KEY_ALL_ACCESS()});
    delete $classes_key -> {$extension};
    reg_delete_recurse($classes_key, "script".$extension);
  } else {
    $classes_key = $Registry -> Open("CUser/Software/Classes/",
        {Access => KEY_ALL_ACCESS()});
    $k = $classes_key->CreateKey($extension);
    $k -> ArrayValues(0);
    $k -> {"/"} = "script".$extension;
    $k = $classes_key->CreateKey("script".$extension."/Shell/Open/Command/");
    $k -> ArrayValues(1);
    $k -> {"/"} = [ '"'.$command.'" "%1" %*',
      ($command =~ /%/) ? REG_EXPAND_SZ : REG_SZ ];
  }
}

=pod

=item C<unregister_script_type($extension)>

Reversal of register_script_type.

=cut

sub unregister_script_type {
  # we don't error check; we just do the best we can.
  my $extension = shift;
  $extension = '.'.$extension unless $extension =~ /^\./; # ensure leading dot
  $extension = uc($extension);
  tllog ($::LOG_DDEBUG, "unregistering $extension\n");
  my $user_env = get_user_env();
  my $system_env = get_system_env();
  my ($pathext, @newpe, $newpex, $e);

  # pathext
  if (!$::opt_portable) {
    tllog ($::LOG_DDEBUG, "Reverting PATHEXT\n");
    if ($is_admin) {
      $pathext = $system_env -> {'/PATHEXT'};
      @newpe = ();
      foreach $e (split(/;/,$pathext)) {
        push @newpe, $e unless (uc($e) eq $extension);
      }
      $newpex = join(";",@newpe);
      setenv_reg("PATHEXT", $newpex, "system");

      $pathext = $user_env -> {'/PATHEXT'};
      if ($pathext) {
        @newpe = ();
        foreach $e (split(/;/,$pathext)) {
          push @newpe, $e unless (uc($e) eq $extension);
        }
        $newpex = join(";",@newpe);
        if ($newpex eq ($system_env -> {"/PATHEXT"})) {
          unsetenv_reg("PATHEXT", "user");
        } else {
          setenv_reg("PATHEXT", $newpex, "user");
        }
      }
    } else {
      $pathext = $user_env -> {'/PATHEXT'};
      $pathext = $system_env -> {'/PATHEXT'} unless $pathext;
      @newpe = ();
      foreach $e (split(/;/,$pathext)) {
        push @newpe, $e unless (uc($e) eq $extension);
      }
      $newpex = join(";",@newpe);
      if ($newpex eq ($system_env -> {"/PATHEXT"})) {
        unsetenv_reg("PATHEXT", "user");
      } else {
        setenv_reg("PATHEXT", $newpex, "user");
      }
    }
  }

  # file type
  tllog ($::LOG_DDEBUG, "Deleting texlua filetype\n");
  $extension = lc($extension);
  my $classes_key = $Registry -> Open("CUser/Software/Classes/",
    {Access => KEY_ALL_ACCESS()});
  if ($classes_key) {
    reg_delete_recurse ($classes_key, $extension."/");
    reg_delete_recurse ($classes_key, "script".$extension."/");
  } else {
    tllog ($::LOG_DDEBUG, "Cannot open HKCU classes for write\n");
  }
  if ($is_admin) {
    $classes_key = $Registry -> Open("LMachine/Software/Classes/",
    {Access => KEY_ALL_ACCESS()});
    if ($classes_key) {
      reg_delete_recurse ($classes_key, $extension."/");
      reg_delete_recurse ($classes_key, "script".$extension."/");
    } else {
    tllog ($::LOG_DDEBUG, "Cannot open HKLM classes for write\n");
    }
    reg_delete_recurse ($classes_key, "script$extension");
  }
}

=pod

=back

=head2 ACTIVATING CHANGES IMMEDIATELY

=over 6

=item C<broadcast_env>

Broadcasts system message that enviroment has changed. This only has
an effect on newly-started programs, not on running programs and the
processes they spawn.

=cut

sub broadcast_env() {
  use constant HWND_BROADCAST	=> 0xffff;
  use constant WM_SETTINGCHANGE	=> 0x001A;
  my $result = "";
  my $SendMessage;
  $wg_error = 0;
  tllog($::LOG_DDEBUG, "Broadcasting \"Enviroment settings changed\" message...\n");
  $SendMessage = new Win32::API('user32', 'SendMessage', 'LLPP', 'L');
  $result = $SendMessage->Call(HWND_BROADCAST, WM_SETTINGCHANGE,
      0, 'Environment') if $SendMessage;
  tllog ($::LOG_DDEBUG, "Broadcast complete; result: $result.\n");
}

=pod

=item C<update_assocs>

Notifies the system that filetypes have changed.

=cut

sub update_assocs() {
  use constant SHCNE_ASSOCCHANGED	=> 0x8000000;
  use constant SHCNF_IDLIST =>	0;
  my $update_fu = new Win32::API('shell32', 'SHChangeNotify', 'LIPP', 'V');
  if ($update_fu) {
    tllog ($::LOG_DDEBUG, "Notifying changes in filetypes...\n");
    $update_fu->Call (SHCNE_ASSOCCHANGED, SHCNF_IDLIST, 0, 0);
    tllog ($::LOG_DDEBUG, "Done notifying\n");
  } else {
    tllog ($::LOG_DDEBUG, "No update_fu\n");
  }
}

=pod

=item C<create_uninstaller>

Writes registry entries for add/remove programs which  reference
the uninstaller script and creates uninstaller batchfiles to finish
the job.

=cut

sub create_uninstaller {
  my $tdfw = shift;
  $tdfw =~ s![\\/]$!!;
  my $td = $tdfw;
  $td =~ s!/!\\!g;

  my $uninst_key = $Registry -> Open((admin() ? "LMachine" : "CUser") .
    "/software/microsoft/windows/currentversion/",
    {Access => KEY_ALL_ACCESS()});
  my $k = $uninst_key->CreateKey("uninstall/TeXLive/");
  $k->{"/DisplayName"} = "TeXLive ".$::texlive_release;
  $k->{"/UninstallString"} = "\"$td\\tlpkg\\installer\\uninst.bat\"";
  $k->{'/DisplayVersion'} = $::texlive_release;
  $k->{'/URLInfoAbout'} = "http://www.tug.org/texlive";

  open UNINST, ">$tdfw/tlpkg/installer/uninst.bat";
  print UNINST <<UNEND;
\@echo off
set PERL5LIB=
\"$td\\tlpkg\\tlperl\\bin\\perl.exe\" \"$td\\texmf\\scripts\\texlive\\uninstall-win32.pl\"
copy \"$td\\tlpkg\\installer\\uninst2.bat\" \"\%TEMP\%\"
\"\%TEMP\%\\uninst2.bat\"
UNEND
  close UNINST;

  open UNINST2, ">$tdfw/tlpkg/installer/uninst2.bat";
  print UNINST2 <<UNEND2;
rmdir /s /q \"$td\\texmf-dist\"
rmdir /s /q \"$td\\texmf-doc\"
rmdir /s /q \"$td\\texmf-var\"
rmdir /s /q \"$td\\texmf-config\"
rmdir /s /q \"$td\\texmf\"
rmdir /s /q \"$td\\temp\"
rmdir /s /q \"$td\\bin\"
rmdir /s /q \"$td\\tlpkg\"
del \"$td\\install-tl.log\"
set test=
for \%\%f in (\"$td\\*.*\") do \@set test=nonempty
if x\%test\%==x rd \"$td\"
\@echo Done uninstalling TeXLive.
\@pause
del %0
UNEND2
  close UNINST2;
}

=pod

=item C<unregister_uninstaller>

Removes TeXLive from Add/Remove Programs.

=cut

sub unregister_uninstaller {
  my $regkey_uninst;
  $regkey_uninst = $Registry->Open(
    "CUser/software/microsoft/windows/currentversion/uninstall/",
    {Access => KEY_ALL_ACCESS()});
  reg_delete_recurse($regkey_uninst, 'texlive') if $regkey_uninst;
  return unless admin();
  $regkey_uninst = $Registry->Open(
    "LMachine/software/microsoft/windows/currentversion/uninstall/",
    {Access => KEY_ALL_ACCESS()});
  reg_delete_recurse($regkey_uninst, 'texlive') if $regkey_uninst;
}

=pod

=back

=cut

# needs a terminal 1 for require to succeed!
1;

__END__