// online2/online-gmm-decodable.h

// Copyright 2012  Cisco Systems (author: Matthias Paulik)
//           2013  Vassil Panayotov
//           2014  Johns Hopkins Universithy (author: Daniel Povey)


// 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.

#ifndef KALDI_ONLINE2_ONLINE_GMM_DECODABLE_H_
#define KALDI_ONLINE2_ONLINE_GMM_DECODABLE_H_

#include "itf/online-feature-itf.h"
#include "matrix/matrix-lib.h"
#include "itf/decodable-itf.h"
#include "gmm/am-diag-gmm.h"
#include "hmm/transition-model.h"

namespace kaldi {


class DecodableDiagGmmScaledOnline : public DecodableInterface {
 public:
  DecodableDiagGmmScaledOnline(const AmDiagGmm &am,
                               const TransitionModel &trans_model,
                               const BaseFloat scale,
                               OnlineFeatureInterface *input_feats);


  /// Returns the scaled log likelihood
  virtual BaseFloat LogLikelihood(int32 frame, int32 index);

  virtual bool IsLastFrame(int32 frame) const;

  virtual int32 NumFramesReady() const;

  /// Indices are one-based!  This is for compatibility with OpenFst.
  virtual int32 NumIndices() const { return trans_model_.NumTransitionIds(); }

 private:
  void CacheFrame(int32 frame);

  OnlineFeatureInterface *features_;
  const AmDiagGmm &ac_model_;
  BaseFloat ac_scale_;
  const TransitionModel &trans_model_;
  const int32 feat_dim_;  // dimensionality of the input features
  Vector<BaseFloat> cur_feats_;
  int32 cur_frame_;
  std::vector<std::pair<int32, BaseFloat> > cache_;

  KALDI_DISALLOW_COPY_AND_ASSIGN(DecodableDiagGmmScaledOnline);
};

} // namespace kaldi

#endif // KALDI_ONLINE2_ONLINE_GMM_DECODABLE_H_