#!/bin/bash
  
  # Copyright 2016    Vimal Manohar
  #           2017    Hossein Hadian
  # Apache 2.0
  
  echo "$0 $@"  # Print the command line for logging
  if [ -f path.sh ]; then . ./path.sh; fi
  . parse_options.sh || exit 1;
  
  if [ $# != 3 ]; then
    echo " Usage: $0 <frame-shift> <srcdir> <destdir>"
    echo "e.g.: $0 -1 data/train data/train_fs-1"
    echo "The script creates a new data directory with the features modified"
    echo "using the program shift-feats with the specified frame-shift."
    echo "This program automatically adds the prefix 'fs<frame-shift>-' to the"
    echo "utterance and speaker names. See also utils/data/shift_and_combine_feats.sh"
    exit 1
  fi
  
  frame_shift=$1
  srcdir=$2
  destdir=$3
  
  
  if [ "$destdir" == "$srcdir" ]; then
    echo "$0: this script requires <srcdir> and <destdir> to be different."
    exit 1
  fi
  
  if [ ! -f $srcdir/feats.scp ]; then
    echo "$0: no such file $srcdir/feats.scp"
    exit 1;
  fi
  
  utt_prefix="fs$frame_shift-"
  spk_prefix="fs$frame_shift-"
  
  mkdir -p $destdir
  utils/copy_data_dir.sh --utt-prefix $utt_prefix --spk-prefix $spk_prefix \
    $srcdir $destdir
  
  if grep --quiet "'" $srcdir/feats.scp; then
    echo "$0: the input features already use single quotes. Can't proceed."
    exit 1;
  fi
  
  awk -v shift=$frame_shift 'NF == 2 {uttid=$1; feat=$2; qt="";} \
  NF > 2 {idx=index($0, " "); uttid=$1; feat=substr($0, idx + 1); qt="\x27";} \
  NF {print uttid " shift-feats --print-args=false --shift=" shift, qt feat qt " - |";}' \
    $destdir/feats.scp >$destdir/feats_shifted.scp
  mv -f $destdir/feats_shifted.scp $destdir/feats.scp
  
  echo "$0: Done"