#!/bin/bash 
  
  # Copyright 2012-2015 Brno University of Technology (author: Karel Vesely)
  # Apache 2.0
  # To be run from .. (one directory up from here)
  # see ../run.sh for example
  
  # Begin configuration section.
  nj=4
  cmd=run.pl
  use_gpu=no
  ivector=
  # End configuration section.
  
  echo "$0 $@"  # Print the command line for logging
  
  if [ -f path.sh ]; then . ./path.sh; fi
  . parse_options.sh || exit 1;
  
  set -euo pipefail
  
  if [ $# != 2 ]; then
     echo "usage: $0 [options] <data-dir> <nnet-dir>";
     echo "options: "
     echo "  --cmd 'queue.pl <queue opts>'   # how to run jobs."
     echo "  --nj <nj>                       # number of parallel jobs"
     echo "  --remove-last-components <N>    # number of NNet Components to remove from the end"
     echo "  --use-gpu (no|yes|optional)     # forwarding on GPU"
     exit 1;
  fi
  
  if [ -f path.sh ]; then . ./path.sh; fi
  
  data=$1
  nndir=$2
  
  ######## CONFIGURATION
  
  required="$data/feats.scp $nndir/final.nnet $nndir/final.feature_transform"
  for f in $required; do
    [ ! -f $f ] && echo "$0: Missing $f" && exit 1;
  done
  
  sdata=$data/split$nj
  [[ -d $sdata && $data/feats.scp -ot $sdata ]] || split_data.sh $data $nj || exit 1;
  
  echo "Accumulating prior stats by forwarding '$data' with '$nndir'"
  
  # We estimate priors on 10k utterances, selected randomly from the splitted data,
  N=$((10000/nj))
  
  # PREPARE FEATURE EXTRACTION PIPELINE
  # import config,
  cmvn_opts=
  delta_opts=
  D=$nndir
  [ -e $D/norm_vars ] && cmvn_opts="--norm-means=true --norm-vars=$(cat $D/norm_vars)" # Bwd-compatibility,
  [ -e $D/cmvn_opts ] && cmvn_opts=$(cat $D/cmvn_opts)
  [ -e $D/delta_order ] && delta_opts="--delta-order=$(cat $D/delta_order)" # Bwd-compatibility,
  [ -e $D/delta_opts ] && delta_opts=$(cat $D/delta_opts)
  #
  # Create the feature stream,
  feats="ark:cat $sdata/JOB/feats.scp | utils/shuffle_list.pl --srand 777 | head -n$N | copy-feats scp:- ark:- |"
  # apply-cmvn (optional),
  [ ! -z "$cmvn_opts" -a ! -f $sdata/1/cmvn.scp ] && echo "$0: Missing $sdata/1/cmvn.scp" && exit 1
  [ ! -z "$cmvn_opts" ] && feats="$feats apply-cmvn $cmvn_opts --utt2spk=ark:$sdata/JOB/utt2spk scp:$sdata/JOB/cmvn.scp ark:- ark:- |"
  # add-deltas (optional),
  [ ! -z "$delta_opts" ] && feats="$feats add-deltas $delta_opts ark:- ark:- |"
  # add-pytel transform (optional),
  [ -e $D/pytel_transform.py ] && feats="$feats /bin/env python $D/pytel_transform.py |"
  
  # add-ivector (optional),
  if [ -e $D/ivector_dim ]; then
    [ -z $ivector ] && echo "Missing --ivector, they were used in training!" && exit 1
    # Get the tool, 
    ivector_append_tool=append-vector-to-feats # default,
    [ -e $D/ivector_append_tool ] && ivector_append_tool=$(cat $D/ivector_append_tool)
    # Check dims,
    feats_job_1=$(sed 's:JOB:1:g' <(echo $feats))
    dim_raw=$(feat-to-dim "$feats_job_1" -)
    dim_raw_and_ivec=$(feat-to-dim "$feats_job_1 $ivector_append_tool ark:- '$ivector' ark:- |" -)
    dim_ivec=$((dim_raw_and_ivec - dim_raw))
    [ $dim_ivec != "$(cat $D/ivector_dim)" ] && \
      echo "Error, i-vector dim. mismatch (expected $(cat $D/ivector_dim), got $dim_ivec in '$ivector')" && \
      exit 1
    # Append to feats,
    feats="$feats $ivector_append_tool ark:- '$ivector' ark:- |"
  fi
  
  # Run the forward pass,
  $cmd JOB=1:$nj $nndir/log/prior_stats.JOB.log \
    nnet-forward --use-gpu=$use_gpu --feature-transform=$nndir/final.feature_transform $nndir/final.nnet "$feats" ark:- \| \
    compute-cmvn-stats --binary=false ark:- $nndir/JOB.prior_cmvn_stats || exit 1
  
  sum-matrices --binary=false $nndir/prior_cmvn_stats $nndir/*.prior_cmvn_stats 2>$nndir/log/prior_sum_matrices.log || exit 1
  rm $nndir/*.prior_cmvn_stats
  
  awk 'NR==2{ $NF=""; print "[",$0,"]"; }' $nndir/prior_cmvn_stats >$nndir/prior_counts || exit 1
      
  echo "Succeeded creating prior counts '$nndir/prior_counts' from '$data'"