#!/usr/bin/perl -w
######################################################################
#
# Copyright 2007-2018 by Wilson Snyder.  This package is free software; you
# can redistribute it and/or modify it under the terms of either the GNU
# Lesser General Public License Version 3 or the Perl Artistic License
# Version 2.0.
#
# This program 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.
#
######################################################################

# DESCRIPTION: Diff bison files

use Getopt::Long;
use IO::File;
use strict;

our $Debug;
our $Opt_Unsup;

if (! GetOptions (
	  #"help"	=> \&usage,
	  "debug"	=> sub { $Debug = 1; },
	  "unsup!"	=> \$Opt_Unsup,		# Ignore unsupported
    )) {
    die "usage();"
}

diff($ARGV[0],$ARGV[1]);

sub diff {
    my $a=shift;
    my $b=shift;

    my $ta = "/tmp/bisondiff.$$.a";
    my $tb = "/tmp/bisondiff.$$.b";

    prep($a,$ta);
    prep($b,$tb);

    system("diff -u -w $ta $tb");
}

sub prep {
    my $filename = shift;
    my $wfilename = shift;

    my $fh = IO::File->new("<$filename") or die "%Error: $! $filename";
    my $fho = IO::File->new(">$wfilename") or die "%Error: $! writing $wfilename";

    my %declared;
    my %used;

    my $body = 0;
    my $rule = "";
    my $skip = 1;
    while (defined(my $line = $fh->getline)) {
	if ($skip == 1) {
	    next if $line !~ /%token/;
	    $skip = 2;
	}

	if ($Opt_Unsup) {
	    $line =~ s!//UNSUP!|!g;
	    $line =~ s!(\s+)\|(\s+)!$1$2!g;  # As "UNSUP" often replaces "|"
	}

	# %type<foo>
	$line =~ s/^(%\S+)<(\S+)>/$1/;
	# rule<foo>
	$line =~ s/^([a-zA-Z0-9_]+)<\S+>:/$1:/;
	# Productions
	$line =~ s/[ \t]{[^}]*?}/\t{}/g;

	$fho->print($line);
    }
}

# Local Variables:
# compile-command: "./bisondiff --unsup $VP/Parser/VParseBison.y ../src/verilog.y"
# End:
