#!/usr/bin/env perl
# $Id$
# Originally written by Norbert Preining and Karl Berry, 2015.  Public domain.
# 
# Determine the files on which each format (fmt/base) depends
#   (by running fmtutil -recorder),
# then map those files to TL packages,
# then check that exactly those packages are listed as triggers in the
#   corresponding tlpsrc files.
# 
# Cleaner approach: should output exact list of deps for each format,
# and then use it. That would be easier to maintain than the current
# complicated set of variables.

my $vc_id = '$Id$';
my $Master;

BEGIN {
  $^W = 1;
  $| = 1;
  (my $mydir = $0) =~ s,/[^/]*$,,;
  my $tlroot = "$mydir/../..";
  unshift (@INC, "$tlroot/tlpkg");
  chomp ($Master = `cd $mydir/../.. && pwd`);
}

use File::Find;
use Getopt::Long;
use Pod::Usage;

use TeXLive::TLConfig;
use TeXLive::TLUtils qw(info debug ddebug debug_hash tlwarn tldie);

my $prg = TeXLive::TLUtils::basename($0);

my $opt_analyze = 0;
my $opt_fmtargs = "--all";
my $opt_fmtdir = "/tmp/fmttriggers";
my $opt_rerecord = 1;
my $opt_tlpdb = undef;
my $opt_help = 0;
my $opt_version = 0;

TeXLive::TLUtils::process_logging_options ();
GetOptions (
  "analyze"    => \$opt_analyze,
  "fmtargs=s"  => \$opt_fmtargs,
  "fmtdir=s"   => \$opt_fmtdir,
  "rerecord!"  => \$opt_rerecord,
  "tlpdb=s"    => \$opt_tlpdb,
  "version"    => \$opt_version,
  "help|?"     => \$help) || pod2usage(1);

pod2usage ("-exitstatus" => 0, "-verbose" => 2) if $help;
if ($opt_version) { print "$vc_id\n"; exit 0; } 

# These don't have triggers, and that's ok.
my $no_triggers_ok = '^(mf-nowin\.mf|(pdf|xe)tex\.cont-en)$';

exit (&main());


sub main {
  $::installerdir = $Master;  # TLUtils.pm should be smarter
  $ENV{'PATH'} = "$Master/bin/" . TeXLive::TLUtils::platform() . ":$ENV{PATH}";

  # no interference from TEXMFHOME, etc.
  $ENV{'TEXMFHOME'}   = "/nonesuch-home";
  $ENV{'TEXMFVAR'}    = "/nonesuch-uvar";
  $ENV{'TEXMFCONFIG'} = "/nonesuch-uconfig";
  $ENV{'TEXMFLOCAL'}  = "/nonesuch-local";

  if ($opt_rerecord && ! $opt_analyze) {  # remake recorder files?
    my $status = &run_fmtutil ($opt_fmtdir);
    return $status if $status;
  }
  #system ("bytime $opt_fmtdir");
  
  # read tlpdb.
  my $tlpdb_file = $opt_tlpdb || "$Master/tlpkg/texlive.tlpdb";
  my ($tlpdb,$fmttriggers,$fmtpkgcontainers) = &tlpdb_by_file ($tlpdb_file);
 
  # if reporting on the trigger subsets, just do that and we're done.
  if ($opt_analyze) {
    &analyze_triggers ($fmttriggers);
    return 0;
  }
  
  # read recorder files.
  my %files_per_format = &files_per_format ($opt_fmtdir);

  # map files used in the format builds to packages.
  my %pkgs_per_format = &pkgs_per_format ($tlpdb, %files_per_format);
  
  # check that those packages are exactly what's listed as needed.
  my $ret = &compare_pkgs_and_triggers (\%pkgs_per_format,
                                        $fmttriggers,
                                        $fmtpkgcontainers);
  info ("Exit status: $ret\n");
  return $ret;
}


# Run fmtutil --fmtdir=$OUTDIR --recorder ..., to recreate the recorder
# files which are the basis for finding the dependencies.
# 
# OUTDIR is completely removed first (!!), on the theory that this job
# should only be done in temporary directories.
# 
sub run_fmtutil {
  my ($outdir) = @_;
  
  # yep, destroy output directory tree.
  TeXLive::TLUtils::rmtree ($outdir);
  mkdir ($outdir, 0775) || die "$prg: mkdir($outdir) failed: $!";
  
  # the output from fmtutil can be useful in debugging.
  my $logfile = "$outdir/fmtutil.log";
  my $cmd = "fmtutil --sys --recorder --strict --fmtdir=$outdir "
             . "$opt_fmtargs >$logfile 2>&1";
  &info ("Running $cmd\n");
  my $retval = system ($cmd);
  $retval >>= 8 if $retval > 0;
  if ($retval) {
    tlwarn ("fmtutil exit status = $retval; contents of $logfile =\n");
    tlwarn (`cat $logfile`);
    tldie ("fmtutil failed, goodbye.\n");
  }
  return $retval;
}


# Return a hash with each key being a string of the form ENGINE.FORMAT,
# and the corresponding value a reference to the list of files used to
# make that format with that engine.  This is based on reading the
# recorder files (format.fls/.ofl) for the format in FMTDIR.
# Uninteresting files are removed from the list, as is the Master
# directory prefix.
# 
sub files_per_format {
  my ($fmtdir) = @_;
  my %ret;
  
  # gather all fls files.
  my @fls = ();
  my $recorder_files = sub {
    # fun with perl: we use an anonymous sub because it's lexically scoped,
    #   hence we can update a my variable (@fls) inside.  Explanation at, e.g.,
    #   http://stackoverflow.com/questions/8839005
    # In this case, we could also pass a lambda sub to find, since
    #   this sub is so simple, but for purposes of example, do it this way.
    push (@fls, $File::Find::name)
      if $File::Find::name =~ /\.(fls|ofl)$/
  };
  File::Find::find ($recorder_files, $fmtdir);
  
  # each fls file will become an entry in the return hash.
  my $fls_count = @fls;
  &info ("Reading $fls_count fls file(s): @fls\n");
  for my $fls_name (@fls) {
    open (my $fls, $fls_name) || die "open($fls_name) failed: $!";
    my @files = ();
    while (<$fls>) {
      next unless s/^INPUT //;
      next if m,/web2c/texmf\.cnf$,;       # read internally by kpathsea
      next if m,/fontname/texfonts\.map$,; # likewise
      next if m,/texsys\.aux$,;            # aux file created during run
      chomp;
      s,^${Master}/,,;			   # rm prefix
      push (@files, $_);
    }
    close ($fls) || warn "close($fls_name) failed: $!";
    
    # The engine name is the directory above the format file,
    # and the format name is the format file without extension.
    my ($engine,$format) = ($fls_name =~ m!^.*/([^/]+)/([^/.]+)\.[^/]+$!);
    #
    # we'd have to have a similar special case for mpost if mem files
    # were still used (see rebuild_one_format in fmtutil).
    $engine = "mf-nowin" if $engine eq "metafont";
    #
    my $ef = "$engine.$format";

    # Unfortunately, format filenames themselves are not unique, due to
    # cont-en and pdfcsplain.  Shouldn't be any engine+format dups, though.
    # 
    tldie ("$prg: already saw format $ef\n (with files @{$ret{$ef}}),\n"
           . "  files now = @files\n")
      if exists $ret{$ef};
    $ret{$ef} = \@files;
  }

  #&debug_hash ("files_per_format returning hash", %ret);
  return %ret;
}


# Read TLPDB_FILE and return references to three hashes:
# the first mapping contained files to TL package names, 
# the second mapping engine.format names to their specified fmttriggers,
# the third mapping engine.format names to the package defining them.
# 
# Instead of using the general TeXLive::TLPDB functions, read the tlpdb
# file ourselves.  We want to build the file->package mapping just once,
# for all files, or things become noticeably slow.  (The tlpfiles script
# does this too, but we repeat that code here because we want to find
# the fmttriggers too.)
#
sub tlpdb_by_file {
  my ($tlpdb_file) = @_;
  my (%tlpfiles, %fmttriggers, %fmtpkgcontainers);
  
  open (my $tlpdb, $tlpdb_file) || die "open($tlpdb_file) failed: $!";
  my $pkg;
  while (<$tlpdb>) {
    chomp;
    if (/^name /) {  # notice package names
      (undef,$pkg) = split (/ /);

    } elsif (s/^execute +AddFormat +//) {  # notice AddFormat lines
      my %af = TeXLive::TLUtils::parse_AddFormat_line ($_);
      if (exists $af{"error"}) {
        tldie ("$prg: parse_AddFormat_line failed: $af{error}\n"
               . "line = $_\n");
      }
      
      next if $af{"mode"} == 0; # skip disabled.
      
      my $ef = "$af{engine}.$af{name}";
      if ($af{"fmttriggers"}) {
        if (exists ($fmttriggers{$ef})) {
          tldie ("$prg: already saw triggers for $ef ($fmttriggers{$ef}),"
                 . "  triggers now = $af{fmttriggers}\n");
        }
        $fmttriggers{$ef} = $af{"fmttriggers"};
        $fmtpkgcontainers{$ef} = $pkg;
        #warn "  fmtpkgcontainers{$ef} = $pkg\n";
      } else {
        tlwarn ("$prg: no fmttriggers: $_\n") unless $ef =~ /$no_triggers_ok/;
      }

    } elsif (s/^ //) { # notice file names
      # we carefully designed the format so that the only lines with
      # leading spaces are the files.
      # The installer "package" isn't one, just ignore it.
      next if $pkg eq "00texlive.installer";
      my $f = $_;
      tlwarn ("$prg: already saw file $f (package $tlpfiles{$f}),"
              . " now in package $pkg\n")
        if exists $tlpfiles{$f}; # should never happen
      $tlpfiles{$f} = $pkg;
    }
  }
  close ($tlpdb) || warn "close($tlpdb_file) failed: $!";
  
  &info ("TLPDB files: " . scalar (keys %tlpfiles)
         . "  triggers: " . scalar (keys %fmttriggers)
         . "  file: $tlpdb_file\n" );
  return (\%tlpfiles, \%fmttriggers, \%fmtpkgcontainers);
}
  

# Return a hash with each key being a format name and the corresponding
# value a reference to the list of TL packages which contain the files
# used to make that format, based on the incoming TLPDB and FILES_PER_FORMAT.
# 
sub pkgs_per_format {
  my ($tlpdb,%files_per_format) = @_;
  my %ret;  # format->pkgs mapping

  for my $format (sort keys %files_per_format) {
    &debug ("finding packages for $format...\n");
    my %pkgs_for_this_format;
    my $files_ref = $files_per_format{$format};
    for my $f (@$files_ref) {
      next if $f eq "/dev/null";
      if (exists $tlpdb->{$f}) {
        my $pkg = $tlpdb->{$f};
        $pkgs_for_this_format{$pkg} = 1;
      } else {
        tlwarn ("$prg: tl package not found for file: $f\n");
      }
    }

    # looked up all files for this format; save our list of packages.
    my @pkgs = sort keys %pkgs_for_this_format;
    &debug ("  packages for $format: @pkgs\n");
    if (@pkgs == 0) {
      tlwarn ("$prg: no packages for format $format?  files = @$files_ref\n");
    }
    $ret{$format} = \@pkgs;
  }

  &info ("Formats found: " . scalar (keys %ret) . "\n");
  #&debug_hash ("pkgs_per_format returning", %ret);
  return %ret;
}


# Compare lists of packages required by building (PKGS_PER_FORMAT) with
# lists of existing trigger directives (FMTTRIGGERS). Return 0 if
# identical, 1 otherwise (and report differences). Ignore some
# hyphenation dependencies, the package itself containing the trigger
# directive (FMTPKGCONTAINERS), and various other dependencies we
# specify to ease maintenance.
# 
sub compare_pkgs_and_triggers {
  my ($pkgs_per_format,$fmttriggers,$fmtpkgcontainers) = @_;
  my $bad_p = 0;
  my $all_pkgs = 0;
  
  for my $ef (sort keys %$pkgs_per_format) {
    my @recorded_pkgs = @{$pkgs_per_format->{$ef}};
    $all_pkgs += @recorded_pkgs;

    my %recorded_pkgs;
    @recorded_pkgs{@recorded_pkgs} = ();  # hash slice for recorded pkgs

    if (defined $fmttriggers->{$ef}) {
      my @tlpdb_pkgs = @{$fmttriggers->{$ef}};
      my %tlpdb_pkgs;
      @tlpdb_pkgs{@tlpdb_pkgs} = ();       # hash slice for tlpdb pkgs

      my @recorded_only = ();
      for my $r (keys %recorded_pkgs) {
        # no need for a package to include itself as a fmttrigger.
        next if $r eq $fmtpkgcontainers->{$ef};
        
        if (exists $tlpdb_pkgs{$r}) {
          delete $tlpdb_pkgs{$r}; # ok, in both
        } else {
          # The hyphen-* packages get loaded anyway? Not sure.
          next if $r =~ /hyph-utf8|hyphen-.*/;
          next if $r =~ /dehyph|dehyph-exptl|ruhyph|ukrhyph/;
          push (@recorded_only, $r);
        }
      }
      if (keys %tlpdb_pkgs) {
        # These packages are included as fmttriggers even though they
        # are not always used, usually to simplify maintenance of the
        # package lists. So don't worry about them if they are present.
        # See 00texlive.autopatterns.tlpsrc for more.
        # 
        # luaotfload doesn't show up in the recorder output,
        # unfortunately. It's used in the lualatex patterns.
        # 
        my @skip_tlpdb = qw(firstaid l3backend l3kernel latex
                            luaotfload
                            tex-ini-files unicode-data);
        my %skip_tlpdb; @skip_tlpdb{@skip_tlpdb} = 1; # make into hash
        
        for my $t (keys %tlpdb_pkgs) {
          delete $tlpdb_pkgs{$t} if exists $skip_tlpdb{$t};
        }
        if (keys %tlpdb_pkgs) {
          tlwarn ("$prg: $ef triggers only in tlpdb: "
                  . join (",", sort keys %tlpdb_pkgs)
                  . "\n");
          $bad_p = 1;
        }
      }
      if (@recorded_only) {
        tlwarn ("$prg: $ef triggers only in recorder: "
                . join (",", sort @recorded_only) . "\n");
        $bad_p = 1;
      }
      
      delete $fmttriggers->{$ef};

    } else {
      # not in tlpdb at all; in a few cases, that is expected.
      # Otherwise, complain and output needed fmttriggers directive.
      if ($ef =~ /$no_triggers_ok/) {
        delete $fmttriggers->{$ef}; # ok
      } else {
        tlwarn ("$prg: no fmttriggers in tlpdb: $ef\n"
                . "  fmttriggers=" . join (",", @recorded_pkgs) . "\n");
        $bad_p = 1;
      }
    }
  }
  
  for my $ef (sort keys %$fmttriggers) {
    my $trig = join (",", sort @{$fmttriggers->{$ef}});
    tlwarn ("$prg: format in tlpdb only: "
            . "$ef ($trig)\n");
    $bad_p = 1;
  }
  
  info ("Triggers checked: $all_pkgs (includes duplicates)\n");
  return $bad_p;
}


sub analyze_triggers {
  my ($fmttriggers) = @_;
  my %fmttriggers = %$fmttriggers;
  
  my %by_pkg;
  for my $ef (sort keys %fmttriggers) {
    next if $ef =~ /(aleph|lamed|jadetex|mex)$/; # these are taken care of
    my @pkgs = @{$fmttriggers{$ef}};
    #print "$ef => @pkgs\n";
    for my $p (@pkgs) {
      $by_pkg{$p} .= " $ef";
    }
  }
  
  for my $p (sort { ($by_pkg{$b} =~ tr/ //) 
                <=> ($by_pkg{$a} =~ tr/ //) } keys %by_pkg) {
    printf "%-14s %2d %s\n", $p, ($by_pkg{$p} =~ tr/ //), $by_pkg{$p};
  }
}

__END__

=head1 NAME

tl-check-fmttriggers - check that all needed packages trigger format rebuilds

=head1 SYNOPSIS

check-fmttriggers [I<option>]...

=head1 OPTIONS

=over 4

=item B<--analyze>

Instead of the usual dependency check described below, merely report the
list of I<engine>.I<format> which each package is a dependency for,
sorted by the number of I<engine>.I<format>s. This provides some
information for creating common dependencies, which can then be defined
as C<global_> tlpvars in C<00texlive.autopatterns.tlpsrc>, to increase
maintainability. (It does not actually try to figure out any tlpvars or
which packages to use them in, just reports counts.)

=item B<--fmtargs> I<str>

Pass I<str> to C<fmtutil>, overriding C<--all>; e.g., for debugging you
might want C<--fmtargs=--byfmt=tex> to build only C<tex.fmt>.  (Many
inconsistencies with the TLPDB will be reported, naturally.)

=item B<--fmtdir> I<dir>

Rebuild formats in I<dir>; default C</tmp/fmttriggers>.  This directory
is completely removed before rebuilding, so do not use any system
directory.

=item B<--no-rerecord>

Do not rebuild all formats to remake the recorder files; the default
(C<--rerecord>) is to do so.

=item B<--help>

Display this documentation and exit.

=item B<--version>

Display version information and exit.

=back

The standard options B<-q>, B<-v>, and B<-logfile>=I<file> are also
accepted; see the C<process_logging_options> function in
L<TeXLive::TLUtils> for details.  In particular, with B<-v> or higher,
the packages found to be needed for each I<engine.format> combination
will be reported.

=head1 DESCRIPTION

Compare the fmttriggers= listed in the tlpsrc files with the actual
dependencies found by running fmtutil -recorder and inspecting the
recorder (.fls) files.

=head1 AUTHORS AND COPYRIGHT

This script and its documentation were written for the TeX Live
distribution (L<http://tug.org/texlive>) and both are licensed under the
GNU General Public License Version 2 or later.

=cut

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