#!/bin/bash
  
  # Copyright 2014  Guoguo Chen
  # Apache 2.0
  
  # This script reads in an Arpa format language model, and converts it into the
  # ConstArpaLm format language model.
  
  # begin configuration section
  # end configuration section
  
  [ -f path.sh ] && . ./path.sh;
  
  . utils/parse_options.sh
  
  if [ $# != 3 ]; then
    echo "Usage: "
    echo "  $0 [options] <arpa-lm-path> <old-lang-dir> <new-lang-dir>"
    echo "e.g.:"
    echo "  $0 data/local/lm/3-gram.full.arpa.gz data/lang/ data/lang_test_tgmed"
    echo "Options"
    exit 1;
  fi
  
  export LC_ALL=C
  
  arpa_lm=$1
  old_lang=$2
  new_lang=$3
  
  mkdir -p $new_lang
  
  mkdir -p $new_lang
  cp -r $old_lang/* $new_lang
  
  unk=`cat $new_lang/oov.int`
  bos=`grep "^<s>\s" $new_lang/words.txt | awk '{print $2}'`
  eos=`grep "^</s>\s" $new_lang/words.txt | awk '{print $2}'`
  if [[ -z $bos || -z $eos ]]; then
    echo "$0: <s> and </s> symbols are not in $new_lang/words.txt"
    exit 1
  fi
  
  
  arpa-to-const-arpa --bos-symbol=$bos \
    --eos-symbol=$eos --unk-symbol=$unk \
    "gunzip -c $arpa_lm | utils/map_arpa_lm.pl $new_lang/words.txt|"  $new_lang/G.carpa  || exit 1;
  
  exit 0;