#!/usr/bin/perl

#
# 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's license is available here:
# 	http://www.use-strict.de/files/software/LICENSE.txt

# There's no warranty at all - Use at own risk!

use strict;

die "usage: $0 [file|-]\n" if (@ARGV != 1);

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

open FH, $input or die "Cannot open file '$input':\n\t$!\n";

my @dotfile;
push @dotfile, "# automatically generated by $0\n" .
    "digraph agraph {\n\tnode [shape=\"circle\",label=\"\"];\n";
        
foreach(<FH>){
    chomp;
    if (/^(\d+)\t([^\t]+)\t(\d+)$/) {
        push @dotfile, "\n\t$1 -> $3 [label=\"$2\"];";
    }
    elsif (/^final: (\d+)$/) {
        push @dotfile, "\n\t$1 [shape=\"doublecircle\"]";
    }
    else {
        print STDERR "error parsing line: '$_'\n";
        exit 1;
    }
}

print @dotfile, "\n}\n";