#!/usr/bin/perl -w

#
# Alex Linke <alex@use-strict.de>
#
# A short introduction on the filter's usage can be found here:
#       http://www.use-strict.de/software/fst2dot.html
#
# The filter is available under the terms of the MIT license:
#       http://www.use-strict.de/files/software/LICENSE.txt
#
# Changelog:
#   2009-10-10 (0.2) -- Updated to new fst-print(1) format (SFST >= 1.3)
#                    -- Various cleanups and tiny improvements
#   2006-05-17 (0.1) -- Initial release
#     

use strict;

my $VERSION = "0.2";

die "fst2dot v$VERSION\n\nusage: $0 [file|-]\n" if (scalar(@ARGV) != 1);

my $input = $ARGV[0] eq '-' ? '/dev/stdin' : $ARGV[0];

open FH, $input or die "$input: $!\n";


my @nodes;

foreach my $line (<FH>)
{
    chomp($line);

    # i.e.: "0    1    B    B"
    if ($line =~ /^(\d+)\t(\d+)\t([^\s]+)\t([^\s]+)$/)
    {
        my $label = $3 eq $4 ? $3 : "$3:$4";

        push @nodes, qq(\n\t$1 -> $2 [label="$label"];);
    }
    elsif ($line =~ /^(\d+)$/)
    {
        push @nodes, qq(\n\t$1 [shape="doublecircle"]);
    }
    else
    {
        die "Error parsing line: '$line'\n";
    }
}

close FH;


die "No nodes extracted\n" unless scalar(@nodes);


@nodes = sort(@nodes);

print <<DOTFILE;
# automatically generated by fst2dot v$VERSION

digraph agraph
{
\trankdir="LR";
\tnode [shape="circle", label=""];
@nodes
}
DOTFILE


# vim: sts=4 sw=4 enc=utf-8 ai et