#!/bin/bash
  
  # Copyright 2012  Johns Hopkins University (Author: Daniel Povey).  Apache 2.0.
  
  # This script does decoding with an SGMM system, by rescoring lattices
  # generated from a previous SGMM system.  The directory with the lattices
  # is assumed to contain speaker vectors, if used.  Basically it rescores
  # the lattices one final time, using the same setup as the final decoding
  # pass of the source dir.  The assumption is that the model may have
  # been discriminatively trained.
  
  # If the system was built on top of fMLLR transforms from a conventional system,
  # you should provide the --transform-dir option.
  
  # Begin configuration section.
  transform_dir=    # dir to find fMLLR transforms.
  cmd=run.pl
  iter=final
  skip_scoring=false
  scoring_opts=
  # End configuration section.
  
  echo "$0 $@"  # Print the command line for logging
  
  [ -f ./path.sh ] && . ./path.sh; # source the path.
  . parse_options.sh || exit 1;
  
  if [ $# -ne 4 ]; then
    echo "Usage: steps/decode_sgmm2_rescore.sh [options] <graph-dir|lang-dir> <data-dir> <old-decode-dir> <decode-dir>"
    echo " e.g.: steps/decode_sgmm2_rescore.sh --transform-dir exp/tri3b/decode_dev93_tgpr \\"
    echo "      exp/sgmm3a/graph_tgpr data/test_dev93 exp/sgmm3a/decode_dev93_tgpr exp/sgmm3a_mmi/decode_dev93_tgpr"
    echo "main options (for others, see top of script file)"
    echo "  --transform-dir <decoding-dir>           # directory of previous decoding"
    echo "                                           # where we can find transforms for SAT systems."
    echo "  --config <config-file>                   # config containing options"
    echo "  --cmd <cmd>                              # Command to run in parallel with"
    echo "  --iter <iter>                            # iteration of model to use (default: final)"
    exit 1;
  fi
  
  graphdir=$1
  data=$2
  olddir=$3
  dir=$4
  srcdir=`dirname $dir`; # Assume model directory one level up from decoding directory.
  
  for f in $graphdir/words.txt $data/feats.scp $olddir/lat.1.gz $olddir/gselect.1.gz \
     $srcdir/$iter.mdl; do
    [ ! -f $f ] && echo "$0: no such file $f" && exit 1;
  done
  
  nj=`cat $olddir/num_jobs` || exit 1;
  sdata=$data/split$nj;
  gselect_opt="--gselect=ark,s,cs:gunzip -c $olddir/gselect.JOB.gz|"
  splice_opts=`cat $srcdir/splice_opts 2>/dev/null`
  cmvn_opts=`cat $srcdir/cmvn_opts 2>/dev/null`
  
  mkdir -p $dir/log
  [[ -d $sdata && $data/feats.scp -ot $sdata ]] || split_data.sh $data $nj || exit 1;
  echo $nj > $dir/num_jobs
  
  if [ -f $olddir/vecs.1 ]; then
    echo "$0: using speaker vectors from $olddir"
    spkvecs_opt="--spk-vecs=ark:$olddir/vecs.JOB --utt2spk=ark:$sdata/JOB/utt2spk"
  else
    echo "$0: no speaker vectors found."
    spkvecs_opt=
  fi
  
  
  ## Set up features.
  if [ -f $srcdir/final.mat ]; then feat_type=lda; else feat_type=delta; fi
  echo "$0: feature type is $feat_type"
  
  case $feat_type in
    delta) feats="ark,s,cs:apply-cmvn $cmvn_opts --utt2spk=ark:$sdata/JOB/utt2spk scp:$sdata/JOB/cmvn.scp scp:$sdata/JOB/feats.scp ark:- | add-deltas ark:- ark:- |";;
    lda) feats="ark,s,cs:apply-cmvn $cmvn_opts --utt2spk=ark:$sdata/JOB/utt2spk scp:$sdata/JOB/cmvn.scp scp:$sdata/JOB/feats.scp ark:- | splice-feats $splice_opts ark:- ark:- | transform-feats $srcdir/final.mat ark:- ark:- |"
      ;;
    *) echo "$0: invalid feature type $feat_type" && exit 1;
  esac
  if [ ! -z "$transform_dir" ]; then
    echo "$0: using transforms from $transform_dir"
    [ ! -f $transform_dir/trans.1 ] && echo "$0: no such file $transform_dir/trans.1" && exit 1;
    [ "$nj" -ne "`cat $transform_dir/num_jobs`" ] \
      && echo "$0: #jobs mismatch with transform-dir." && exit 1;
    feats="$feats transform-feats --utt2spk=ark:$sdata/JOB/utt2spk ark,s,cs:$transform_dir/trans.JOB ark:- ark:- |"
  elif grep 'transform-feats --utt2spk' $srcdir/log/acc.0.1.log 2>/dev/null; then
    echo "$0: **WARNING**: you seem to be using an SGMM system trained with transforms,"
    echo "  but you are not providing the --transform-dir option in test time."
  fi
  
  if [ -f $olddir/trans.1 ]; then
    echo "$0: using (in addition to any previous transforms) transforms from $olddir"
    feats="$feats transform-feats --utt2spk=ark:$sdata/JOB/utt2spk ark,s,cs:$olddir/trans.JOB ark:- ark:- |"
  fi
  ##
  
  # Rescore the state-level lattices with the model provided.  Just
  # one command in this script.
  echo "$0: rescoring lattices with SGMM model in $srcdir/$iter.mdl"
  $cmd JOB=1:$nj $dir/log/rescore.JOB.log \
    sgmm2-rescore-lattice "$gselect_opt" $spkvecs_opt \
    $srcdir/$iter.mdl "ark:gunzip -c $olddir/lat.JOB.gz|" "$feats" \
    "ark:|gzip -c > $dir/lat.JOB.gz" || exit 1;
  
  if ! $skip_scoring ; then
    [ ! -x local/score.sh ] && \
      echo "Not scoring because local/score.sh does not exist or not executable." && exit 1;
    local/score.sh $scoring_opts --cmd "$cmd" $data $graphdir $dir ||
      { echo "$0: Scoring failed. (ignore by '--skip-scoring true')"; exit 1; }
  fi
  
  exit 0;