#!/usr/bin/env perl
# $Id$
# Return information given a TL package name (i.e., a tpm file name).
# We use local copies of CTAN and the TeX Catalogue.
# 
exit (&main ());

sub main
{
  $CTAN = $ENV{"CTAN"} || "/home/ftp/tex-archive";
  $TMPDIR = $ENV{"TMPDIR"} || "/tmp";
  $CATALOGUE = $ENV{"TEX_CATALOGUE"} || "/home/httpd/html/catalogue/entries";
  -d "$CATALOGUE/k"
    || die "$0: TEX_CATALOGUE ($CATALOGUE) must point to entries/ subdir"
           . " of a TeX Catalogue checkout.\n";
  
  if ($ARGV[0] eq "--ctan-dir") {
    return &find_ctan_dir ($ARGV[1]);

  } elsif ($ARGV[0] eq "--ctan-root") {
    print "$CTAN\n";
    return 0;

  } else {
    die "Usage: $0 --ctan-dir PKGNAME  or  --ctan-root  (not \"@ARGV\").\n";
  }
}


# 
# Return 0 for success if we find a path (and print it on stdout), else
# return 1.
# 
sub find_ctan_dir
{
  my ($me) = @_;
  return 1 unless $me;  
  
  # regrettably, this list of amslatex packages is duplicated in ctan2tl.
  # unavoidable since ctan throws them all together, but we don't want
  # to, to preserve the package-per-directory name.
  if ($me =~ /^(ams|amscls|amsltx2|amsmath|amsrefs)$/) {
    $me = "amslatex";
  }
  
  # The CTAN path to a package is sometimes stored in the TeX Catalogue,
  # but old entries don't have it, etc.  Still, we want to use it if present.
  my $ctan_dir = &catalogue_find_ctan_path ($me);
  if (! $ctan_dir) {
    # fall back on many special cases
    (my $menobin = $me) =~ s,^bin-,,;
    (my $menopowerdot = $me) =~ s,^powerdot-,,;
    (my $menotype1 = $me) =~ s,-type1$,,;

    for my $dir (
      "macros/latex/contrib/$me",			# most everything
      "macros/latex/contrib/\L$me",		# HA-prosper
      "macros/latex/contrib/powerdot/contrib/$menopowerdot", # powerdot-doc-vn
      "macros/latex/exptl/$me",			# semioneside
      "macros/latex/required/$me",		# babel
      "macros/plain/$me",			# plnfss
      "macros/xetex/latex/$me",			# xetex
      "macros/generic/$me",			# abbr
      "macros/generic/diagrams/$me",		# circ
      "macros/$me",				# eplain
      "support/$me",				# thumbpdf
      "support/$menobin",				# bin-thumbpdf
      "language/vietnamese/$me/unpacked",		# vntex
      "language/hyphenation/$me",			# bghyphen
      "language/hebrew/$me",			# cjhebrew
      "language/greek/package-babel/$me",		# ibycus-babel
      "language/devanagari/$me",		# velthuis
      "language/croatian/$me",			# hrlatex
      "language/coptic/$me",			# cbcoptic
      "info/spanish/$me",			# guia-bibtex
      "info/symbols/$me",			# comprehensive
      "info/math/voss/$me",			# mathmode
      "info/bibtex/$me",				# tamethebeast
      "info/$me",					# Type1fonts
      "help/$me",				# es-tex-faq
      "graphics/$me",				# sparklines
      "graphics/metapost/contrib/macros/$me",	# mpattern
      "graphics/pstricks/contrib/pedigree/$me",	# pst-pdgr
      "graphics/pstricks/contrib/$me",		# pstricks-add
      "fonts/$me",				# MnSymbol
      "fonts/utilities/$me",			# accfonts
      "fonts/ps-type1/$me",			# cm-super
      "fonts/ps-type1/$menotype1",		# esint-type1
      "fonts/greek/$me",				# lfb
      "fonts/gothic/$me",				# blacklettert1
      "fonts/cyrillic/$me/texmf",			# lh
      "fonts/chess/$me",				# skaknew
      "biblio/bibtex/contrib/$me",		# dk-bib
                 ) {
      if (-d "$CTAN/$dir") {
        $ctan_dir = $dir;
        last;
      }
    }

    # names totally dissimilar
    $ctan_dir = "fonts/fourier-GUT" if $me eq "fourier";
    $ctan_dir = "graphics/pdftex" if $me eq "pdftex-def";
    $ctan_dir = "info/biblio" if $me eq "beebe";
    $ctan_dir = "info/epslatex/french" if $me eq "epslatex-fr";
    $ctan_dir = "info/italian/amsldoc" if $me eq "amsldoc-it";
    $ctan_dir = "info/italian/amsthdoc" if $me eq "amsthdoc-it";
    $ctan_dir = "info/tex-references" if $me eq "tex-refs";
    $ctan_dir = "info/translations/vn" if $me eq "ntheorem-vn";
    $ctan_dir = "language/armenian/armtex" if $me eq "armenian";
    $ctan_dir = "language/basque" if $me eq "hyphen-basque";
    $ctan_dir = "language/hungarian/babel" if $me eq "magyar";
    $ctan_dir = "language/hyphenation/elhyphen" if $me eq "hyphen-greek";
    $ctan_dir = "macros/latex/contrib/misc" if $me eq "ltxmisc";
    $ctan_dir = "macros/generic" if $me eq "genmisc";

    # do last, for sake of subdirs above.
    $ctan_dir = "language/hyphenation"
      if $me =~ /^hyphen-/ && ! $ctan_dir;
  }
  
  # prepend ctan root if not an absolute dir (this happens when we make
  # a temp dir).
  $ctan_dir = "$CTAN/$ctan_dir" if $ctan_dir =~ m,^[^/],;
  print "$ctan_dir\n" if $ctan_dir;
  return $ctan_dir ? 0 : 1;
}


# look up ctan path for given package name in catalogue entry.
# xml is too hard to parse, so just look for the <ctan path...> entry.
# Sometimes there is a single file, but worry about that later.
# 
# Return the ctan path if found (without leading /), or undef.
# 
sub catalogue_find_ctan_path
{
  my ($pkgname) = @_;
  
  my $firstchar = substr ($pkgname, 0, 1);
  my $catfile =  "$CATALOGUE/$firstchar/$pkgname.xml";
  return undef unless -r $catfile;

  # get the raw line from the catalogue file.  (let's hope it's one line.)
  my $ctan_path = `sed -n "s,^ *<ctan path='/,,p" $catfile`;
  return undef unless $ctan_path;  # in case it's not present at all

  # extract just the dir or file name, without options, etc.
  (my $ctan_loc = $ctan_path) =~ s,'/>,,;
  $ctan_loc =~ s,' .*,,;
  chomp ($ctan_loc);

  # if the Catalogue lists the path as a single file, there are two
  # possibilities: (1) it really is a single file, e.g., texilikecover,
  # in which case we copy that file into a temp dir and return that temp
  # dir; (2) it is actually in its own directory, e.g., ifxetex, in
  # which case we return undef here and let the code above find it.
  # (The Catalogue maintainers do not consider this a problem for
  # various reasons.)
  # 
  if ($ctan_path =~ /file='true'/) {
    return undef if $ctan_path =~ m,/$pkgname/,;  # pkg dir somewhere in path

    # ok, we will copy to temp dir.
    my $pkgdir = "$TMPDIR/tl.$pkgname";
    system ("rm -rf $pkgdir");
    mkdir ($pkgdir, 0777);
    
    warn "$0: copying single file:\n";
    warn "$0: $CTAN/$ctan_loc\n";
    unless (system ("cp -p '$CTAN/$ctan_loc' '$pkgdir/'") == 0) {
      warn "$0: copy of $CTAN/$ctan_loc to $pkgdir failed?!\n";
      return undef;
    }
    return $pkgdir;
  }

  # ok, we will use the ctan path.  
  return $ctan_loc;
}