#!/bin/bash
  # Copyright 2010-2011 Microsoft Corporation
  
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #  http://www.apache.org/licenses/LICENSE-2.0
  #
  # THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  # KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
  # WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
  # MERCHANTABLITY OR NON-INFRINGEMENT.
  # See the Apache 2 License for the specific language governing permissions and
  # limitations under the License.
  
  
  # This script creates a fully expanded decoding graph (HCLG) that represents
  # all the language-model, pronunciation dictionary (lexicon), context-dependency,
  # and HMM structure in our model.  The output is a Finite State Transducer
  # that has word-ids on the output, and pdf-ids on the input (these are indexes
  # that resolve to Gaussian Mixture Models).  
  # See
  #  http://kaldi-asr.org/doc/graph_recipe_test.html
  # (this is compiled from this repository using Doxygen,
  # the source for this part is in src/doc/graph_recipe_test.dox)
  
  
  N=3
  P=1
  clean=false
  
  for x in 1 2 3; do 
    if [ $1 == "--mono" ]; then
      N=1;
      P=0;
      shift;
    fi
    if [ $1 == "--clean" ]; then
      clean=true
      shift;
    fi
  
  done
  
  if [ $# != 3 ]; then
     echo "Usage: scripts/mkgraph.sh <test-lang-dir> <model-dir> <graphdir>"
     echo "e.g.: scripts/mkgraph.sh data/lang_test exp/tri1/ exp/tri1/graph"
     exit 1;
  fi
  
  if [ -f path.sh ]; then . ./path.sh; fi
  
  lang=$1
  tree=$2/tree
  model=$2/final.mdl
  dir=$3
  
  if $clean; then rm -r $lang/tmp; fi
  
  mkdir -p $dir
  
  tscale=1.0
  loopscale=0.1
  
  # If $lang/tmp/LG.fst does not exist or is older than its sources, make it...
  # (note: the [[ ]] brackets make the || type operators work (inside [ ], we
  # would have to use -o instead),  -f means file exists, and -ot means older than).
  
  required="$lang/L.fst $lang/G.fst $lang/phones_disambig.txt $lang/words.txt $lang/silphones.csl $model $tree"
  for f in $required; do
    [ ! -f $f ] && echo "mkgraph.sh: expected $f to exist" && exit 1;
  done
  
  mkdir -p $lang/tmp
  if [[ ! -f $lang/tmp/LG.fst || $lang/tmp/LG.fst -ot $lang/G.fst || \
        $lang/tmp/LG.fst -ot $lang/L_disambig.fst ]]; then
    fsttablecompose $lang/L_disambig.fst $lang/G.fst | fstdeterminizestar --use-log=true | \
      fstminimizeencoded  > $lang/tmp/LG.fst || exit 1;
    fstisstochastic $lang/tmp/LG.fst || echo "warning: LG not stochastic."
  fi
  
  if [ ! -f $lang/phones_disambig.txt ]; then
    echo "No such file $lang/phones_disambig.txt (supplied a training lang/ directory?)"
    exit 1;
  fi
  
  grep '#' $lang/phones_disambig.txt | awk '{print $2}' > $lang/tmp/disambig_phones.list
  
  
  clg=$lang/tmp/CLG_${N}_${P}.fst
  
  if [[ ! -f $clg || $clg -ot $lang/tmp/LG.fst ]]; then
    fstcomposecontext --context-size=$N --central-position=$P \
     --read-disambig-syms=$lang/tmp/disambig_phones.list \
     --write-disambig-syms=$lang/tmp/disambig_ilabels_${N}_${P}.list \
      $lang/tmp/ilabels_${N}_${P} < $lang/tmp/LG.fst >$clg
    fstisstochastic $clg  || echo "warning: CLG not stochastic."
  fi
  
  if [[ ! -f $dir/Ha.fst || $dir/Ha.fst -ot $model  \
      || $dir/Ha.fst -ot $lang/tmp/ilabels_${N}_${P} ]]; then
    make-h-transducer --disambig-syms-out=$dir/disambig_tid.list \
      --transition-scale=$tscale $lang/tmp/ilabels_${N}_${P} $tree $model \
       > $dir/Ha.fst  || exit 1;
  fi
  
  if [[ ! -f $dir/HCLGa.fst || $dir/HCLGa.fst -ot $dir/Ha.fst || \
        $dir/HCLGa.fst -ot $clg ]]; then
    fsttablecompose $dir/Ha.fst $clg | fstdeterminizestar --use-log=true \
      | fstrmsymbols $dir/disambig_tid.list | fstrmepslocal | \
       fstminimizeencoded > $dir/HCLGa.fst || exit 1;
    fstisstochastic $dir/HCLGa.fst || echo "HCLGa is not stochastic"
  fi
  
  if [[ ! -f $dir/HCLG.fst || $dir/HCLG.fst -ot $dir/HCLGa.fst ]]; then
    add-self-loops --self-loop-scale=$loopscale --reorder=true \
      $model < $dir/HCLGa.fst > $dir/HCLG.fst || exit 1;
  
    if [ $tscale == 1.0 -a $loopscale == 1.0 ]; then
      # No point doing this test if transition-scale not 1, as it is bound to fail. 
      fstisstochastic $dir/HCLG.fst || echo "Final HCLG is not stochastic."
    fi
  fi
  
  # keep a copy of the lexicon and a list of silence phones with HCLG...
  # this means we can decode without refrence to the $lang directory.
  cp $lang/words.txt $dir/
  cp $lang/silphones.csl $dir/
  
  # to make const fst:
  # fstconvert --fst_type=const $dir/HCLG.fst $dir/HCLG_c.fst
  
  echo "Finished making decoding graphs in $dir"