#!/bin/bash
  
  # Compute scores from RNNLM.  This script takes a directory
  # $dir (e.g. dir=local/rnnlm/rnnlm.voc30.hl30 ),
  # where it expects the files:
  #  rnnlm  wordlist.rnn  unk.probs,
  # and also an input file location where it can get the sentences to score, and
  # an output file location to put the scores (negated logprobs) for each
  # sentence.  This script uses the Kaldi-style "archive" format, so the input and
  # output files will have a first field that corresponds to some kind of
  # utterance-id or, in practice, utterance-id-1, utterance-id-2, etc., for the
  # N-best list.
  #
  # Here, "wordlist.rnn" is the set of words, like a vocabulary,
  # that the RNN was trained on (note, it won't include <s> or </s>),
  # plus <RNN_UNK> which is a kind of class where we put low-frequency
  # words; unk.probs gives the probs for words given this class, and it
  # has, on each line, "word prob".
  
  . ./path.sh || exit 1;
  
  rnnlm=$KALDI_ROOT/tools/rnnlm-0.3e/rnnlm
  
  [ ! -f $rnnlm ] && echo No such program $rnnlm && exit 1;
  
  if [ $# != 4 ]; then
    echo "Usage: rnnlm_compute_scores.sh <rnn-dir> <temp-dir> <input-text> <output-scores>"
    exit 1;
  fi
  
  dir=$1
  tempdir=$2
  text_in=$3
  scores_out=$4
  
  for x in rnnlm wordlist.rnn unk.probs; do
    if [ ! -f $dir/$x ]; then 
      echo "rnnlm_compute_scores.sh: expected file $dir/$x to exist."
      exit 1;
    fi
  done
  
  mkdir -p $tempdir
  cat $text_in | awk '{for (x=2;x<=NF;x++) {printf("%s ", $x)} printf("
  ");}' >$tempdir/text
  cat $text_in | awk '{print $1}' > $tempdir/ids # e.g. utterance ids.
  cat $tempdir/text | awk -v voc=$dir/wordlist.rnn -v unk=$dir/unk.probs \
    -v logprobs=$tempdir/loglikes.oov \
   'BEGIN{ while((getline<voc)>0) { invoc[$1]=1; } while ((getline<unk)>0){ unkprob[$1]=$2;} }
    { logprob=0; for (x=1;x<=NF;x++) { w=$x;  
      if (invoc[w]) { printf("%s ",w); } else {
        printf("<RNN_UNK> ");
        if (unkprob[w] != 0) { logprob += log(unkprob[w]); }
        else { print "Warning: unknown word ", w >"/dev/stderr"; logprob += log(1.0e-07); }}}
      printf("
  "); print logprob > logprobs } ' > $tempdir/text.nounk
  
  # OK, now we compute the scores on the text with OOVs replaced
  # with <RNN_UNK>
  
  $rnnlm -independent -rnnlm $dir/rnnlm -test $tempdir/text.nounk -nbest -debug 0 | \
     awk '{print $1*log(10);}' > $tempdir/loglikes.rnn
  
  [ `cat $tempdir/loglikes.rnn | wc -l` -ne `cat $tempdir/loglikes.oov | wc -l` ] && \
    echo "rnnlm rescoring failed" && exit 1;
  
  paste $tempdir/loglikes.rnn $tempdir/loglikes.oov | awk '{print -($1+$2);}' >$tempdir/scores
  
  # scores out, with utterance-ids.
  paste $tempdir/ids $tempdir/scores  > $scores_out