#!/usr/bin/env perl
  #===============================================================================
  # Copyright (c) 2017  Johns Hopkins University
  #                        (Author: Jan "Yenda" Trmal <jtrmal@gmail.com>)
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #  http://www.apache.org/licenses/LICENSE-2.0
  #
  # THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  # KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
  # WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
  # MERCHANTABLITY OR NON-INFRINGEMENT.
  # See the Apache 2 License for the specific language governing permissions and
  # limitations under the License.
  #===============================================================================
  
  use strict;
  use warnings;
  use utf8;
  
  use List::Util qw(max);
  
  binmode(STDOUT, ":utf8");
  binmode(STDERR, ":utf8");
  
  if (@ARGV != 2) {
    print STDERR "Incorrect number of parameters: $ARGV
  ";
    print STDERR "Script expects only one parameter, symbol of unk
  ";
    die "Example: $0 \"<unk>\" data/train/text
  ";
  }
  
  my $unk = $ARGV[0];
  open(my $text, "<:encoding(utf-8)", $ARGV[1])
    or die "Cannot open file $ARGV[1]: $!";
  while(<$text>) {
    chomp;
    next if /<foreign/;
    next if /\[\[NS\]\]/;
    next if /<unclear/;
    (my $utt, my $line) = split / /, $_, 2;
    $line =~ s/{/</g;
    $line =~ s/}/>/g;
    $line =~ s/[,.?^+*]//g;
    $line =~ s/%([^ ]+)/"<" . lc($1) . ">"/ge;
    $line = " $line ";
    $line =~ s/(?<= )[\w]+-(?= )/"$unk"/ge;
    $line =~ s/(?<= )-[\w]+(?= )/"$unk"/ge;
    $line =~ s/(?<= )-[\w]+-(?= )/"$unk"/ge;
    $line =~ s/(?<= )_[\w_]+(?= )/"$unk"/ge;
  
    $line =~ s/^ +//g;
    $line =~ s/ +$//g;
    print "$utt $line
  ";
  }
  close($text);