// latbin/lattice-add-trans-probs.cc

// Copyright 2009-2011  Microsoft Corporation

// See ../../COPYING for clarification regarding multiple authors
//
// 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.


#include "base/kaldi-common.h"
#include "util/common-utils.h"
#include "fstext/fstext-lib.h"
#include "lat/kaldi-lattice.h"
#include "lat/lattice-functions.h"
#include "hmm/transition-model.h"
#include "hmm/hmm-utils.h"

int main(int argc, char *argv[]) {
  try {
    using namespace kaldi;
    typedef kaldi::int32 int32;
    typedef kaldi::int64 int64;
    using fst::SymbolTable;
    using fst::VectorFst;
    using fst::StdArc;

    const char *usage =
        "Add transition probabilities into graph part of lattice scores,\n"
        "controlled by options --transition-scale and --self-loop-scale, which\n"
        "for compatibility with the original graph, would normally be set to the same\n"
        "values used in graph compilatoin\n"
        "\n"
        "Usage: lattice-add-trans-probs [options] model lattice-rspecifier lattice-wspecifier\n"
        " e.g.: lattice-add-trans-probs --transition-scale=1.0 --self-loop-scale=0.1 1.mdl ark:in.lats ark:out.lats\n";
      
    ParseOptions po(usage);

    BaseFloat transition_scale = 1.0, self_loop_scale = 1.0;
    
    po.Register("transition-scale", &transition_scale,
                "Scale for transition probabilities (excluding self-loops)");
    po.Register("self-loop-scale", &self_loop_scale,
                "Probability scale for self-loop vs. non-self-loop "
                "probability mass.");

    po.Read(argc, argv);
    
    if (po.NumArgs() != 3) {
      po.PrintUsage();
      exit(1);
    }

    std::string
        model_rxfilename = po.GetArg(1),
        lats_rspecifier = po.GetArg(2),
        lats_wspecifier = po.GetArg(3);
    
    int32 n_done = 0;

    TransitionModel trans_model;
    
    ReadKaldiObject(model_rxfilename, &trans_model);
    
    SequentialLatticeReader lattice_reader(lats_rspecifier); // read as
    // regular lattice.
    CompactLatticeWriter clat_writer(lats_wspecifier); // write as compact.
    for (; !lattice_reader.Done(); lattice_reader.Next(), n_done++) {
      Lattice lat(lattice_reader.Value());
      AddTransitionProbs(trans_model, transition_scale, self_loop_scale, &lat);
      CompactLattice clat;
      ConvertLattice(lat, &clat);
      clat_writer.Write(lattice_reader.Key(), clat);
      n_done++;
    }
    KALDI_LOG << "Done adding transition probabilities to " << n_done << " lattices.";
    return (n_done != 0 ? 0 : 1);
  } catch(const std::exception &e) {
    std::cerr << e.what();
    return -1;
  }
}