#!/usr/bin/perl
# Copyright      2000 Free Software Foundation, Inc.
#           2023-2026 G. Branden Robinson
#
# This file is part of mm, a reimplementation of the Documenter's
# Workbench (DWB) troff memorandum macro package for use with GNU troff.
#
# mm is distributed with groff, the GNU roff typesetting system.
#
# groff is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free
# Software Foundation, either version 3 of the License, or (at your
# option) any later version.
#
# groff is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Please submit bug reports using groff's 'BUG-REPORT' file to
# http://savannah.gnu.org/bugs/?group=groff.

use strict;
use warnings;

use Config;

(my $progname = $0) =~s @.*/@@;

# Locate groff executable.
my $groff = "groff";
$groff=$ENV{GROFF_COMMAND} if exists ($ENV{GROFF_COMMAND});

sub abort
{
    my $message=shift(@_);
    print STDERR "$progname: fatal error: $message";
    exit 1;
}

sub autopsy
{
    my $waitstatus=shift(@_);
    my $finding;

    if ($waitstatus == -1) {
	$finding = "cannot run $groff: $!\n";
    }
    elsif ($? & 127) {
	$finding = sprintf("$groff died with signal %d, %s core dump\n",
	    ($? & 127),  ($? & 128) ? 'with' : 'without');
    }
    else {
	$finding = sprintf("$groff exited with status %d\n", $? >> 8);
    }

    return $finding;
}

# runs groff in safe mode, that seems to be the default
# installation now. That means that I have to fix all nice
# features outside groff. Sigh.
# I do agree however that the previous way opened a whole bunch
# of security holes.

my $want_only_ref_update = 0;

if (grep(/^--help$/, @ARGV)) {
	print <<EOF;
usage: mmroff [-x] [groff-argument ...]
usage: mmroff --version
usage: mmroff --help

$progname is a simple wrapper for groff(1), used to expand internal
references in mm documents; see groff_mm(7).  It also handles the
inclusion of PostScript images.  Documents that do not use these
features of groff mm (the INITI, IND, INDP, INITR, SETR, GETHN, GETPN,
GETR, GETST, PIC macros) do not require mmroff.  See the mmroff(1)
manual page.
EOF
	exit;
}

if (grep(/^--version$/, @ARGV)) {
	print "mmroff (groff) 1.25.0\n";
	exit;
}

# check for -x and remove it
if (grep(/^-x$/, @ARGV)) {
	$want_only_ref_update = 1;
	@ARGV = grep(!/^-x$/, @ARGV);
}

# mmroff should always have -mm, but not twice
@ARGV = grep(!/^-mm$/, @ARGV);
my $first_pass = "$groff -rRef=1 -z -mm @ARGV";
my $second_pass = "$groff -mm @ARGV";

my (%cur, $rfilename, $imacro, @out, @indi);
my $max_height = 0;
my $max_width = 0;
open(MACRO, "$first_pass 2>&1 |")
	or abort("cannot run pipeline \"$first_pass\": $!");
while(<MACRO>) {
	if (m#^\.\\" Rfilename: (\S+)#) {
		# remove all directories just to be more secure
		($rfilename = $1) =~ s#.*/##;
		next;
	}
	if (m#^\.\\" Imacro: (\S+)#) {
		# remove all directories just to be more secure
		($imacro = $1) =~ s#.*/##;
		next;
	}
	if (m#^\.\\" Index: (\S+)#) {
		# remove all directories just to be more secure
		my $f;
		($f = $1) =~ s#.*/##;
		&print_index($f, \@indi, $imacro);
		@indi = ();
		$imacro = '';
		next;
	}
	my $x;
	if (($x) = m#^\.\\" IND (.+)#) {
		$x =~ s#\\##g;
		my @x = split(/\t/, $x);
		grep(s/\s+$//, @x);
		push(@indi, join("\t", @x));
		next;
	}
	if (m#^\.\\" PIC id (\d+)#) {
		%cur = ('id' => $1);
		next;
	}
	if (m#^\.\\" PIC file (\S+)#) {
		&psbb($1);
		&ps_calc($1);
		next;
	}
	if (m#^\.\\" PIC (\w+)\s+(\S+)#) {
		$cur{"$1"} = '$2';
		next;
	}
	s#\\ \\ $##;
	push(@out, $_);
}
my $waitstatus = close(MACRO);
abort(autopsy($?)) unless $waitstatus == 1; # roughly `WIFEXITED()`

# TODO: We should write out references only if there are any; a document
# that uses only `PIC` might lack them.

if ($rfilename) {
	push(@out, ".nr pict*max-height $max_height\n") if defined $max_height;
	push(@out, ".nr pict*max-width $max_width\n") if defined $max_width;

	open(OUT, ">$rfilename")
		or abort("cannot create file \"$rfilename\": $!");
	print OUT '.\" references', "\n";
	my $i;
	for $i (@out) {
		print OUT $i;
	}
	close(OUT);
}

exit 0 if $want_only_ref_update;
exit system($second_pass);

sub print_index {
	my ($f, $ind, $macro) = @_;

	open(OUT, ">$f") or abort("cannot create file \"$f\": $!");
	my $i;
	for $i (sort @$ind) {
		if ($macro) {
			$i = '.'.$macro.' "'.join('" "', split(/\t/, $i)).'"';
		}
		print OUT "$i\n";
	}
	close(OUT);
}

sub ps_calc {
	return unless exists($cur{'llx'});
	my ($f) = @_;
	my $w = abs($cur{'llx'}-$cur{'urx'});
	my $h = abs($cur{'lly'}-$cur{'ury'});
	$max_width = $w if $w > $max_width;
	$max_height = $h if $h > $max_height;

	my $id = $cur{'id'};
	push(@out, ".ds pict*file!$id $f\n");
	push(@out, ".ds pict*id!$f $id\n");
	push(@out, ".nr pict*llx!$id $cur{'llx'}\n");
	push(@out, ".nr pict*lly!$id $cur{'lly'}\n");
	push(@out, ".nr pict*urx!$id $cur{'urx'}\n");
	push(@out, ".nr pict*ury!$id $cur{'ury'}\n");
	push(@out, ".nr pict*w!$id $w\n");
	push(@out, ".nr pict*h!$id $h\n");
}

sub psbb {
	my ($f) = @_;

	unless (open(IN, $f)) {
		print STDERR "$progname: warning: cannot open"
			. " PostScript file $f: $!\n";
		return;
	}
	while(<IN>) {
		if (/^%%BoundingBox:\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/) {
			$cur{'llx'} = $1;
			$cur{'lly'} = $2;
			$cur{'urx'} = $3;
			$cur{'ury'} = $4;
		}
	}
	close(IN);
}

1;
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