#!/bin/bash
  
  # Copyright 2013  (Author: Daniel Povey, Bagher BabaAli)
  # Apache 2.0
  
  # This script takes data prepared in a corpus-dependent way
  # in data/local/, and converts it into the "canonical" form,
  # in various subdirectories of data/, e.g. data/lang, data/train, etc.
  
  . ./path.sh || exit 1;
  
  echo "Preparing train, dev and test data"
  srcdir=data/local/data
  lmdir=data/local/nist_lm
  tmpdir=data/local/lm_tmp
  lexicon=data/local/dict/lexicon.txt
  mkdir -p $tmpdir
  
  # Next, for each type of language model, create the corresponding FST
  # and the corresponding lang_test_* directory.
  
  echo Preparing language models for test
  
  for lm_suffix in bg; do
    test=data/lang_test_${lm_suffix}
    mkdir -p $test
    cp -r data/lang/* $test
  
    gunzip -c $lmdir/lm_phone_${lm_suffix}.arpa.gz | \
      arpa2fst --disambig-symbol=#0 \
               --read-symbol-table=$test/words.txt - $test/G.fst
    fstisstochastic $test/G.fst
   # The output is like:
   # 9.14233e-05 -0.259833
   # we do expect the first of these 2 numbers to be close to zero (the second is
   # nonzero because the backoff weights make the states sum to >1).
   # Because of the <s> fiasco for these particular LMs, the first number is not
   # as close to zero as it could be.
  
   # Everything below is only for diagnostic.
   # Checking that G has no cycles with empty words on them (e.g. <s>, </s>);
   # this might cause determinization failure of CLG.
   # #0 is treated as an empty word.
    mkdir -p $tmpdir/g
    awk '{if(NF==1){ printf("0 0 %s %s
  ", $1,$1); }} END{print "0 0 #0 #0"; print "0";}' \
      < "$lexicon"  >$tmpdir/g/select_empty.fst.txt
    fstcompile --isymbols=$test/words.txt --osymbols=$test/words.txt $tmpdir/g/select_empty.fst.txt | \
     fstarcsort --sort_type=olabel | fstcompose - $test/G.fst > $tmpdir/g/empty_words.fst
    fstinfo $tmpdir/g/empty_words.fst | grep cyclic | grep -w 'y' &&
      echo "Language model has cycles with empty words" && exit 1
    rm -r $tmpdir/g
  done
  
  utils/validate_lang.pl data/lang_test_bg || exit 1
  
  echo "Succeeded in formatting data."
  rm -r $tmpdir