// lm/arpa-lm-compiler.h
  
  // Copyright 2009-2011 Gilles Boulianne
  // Copyright 2016 Smart Action LLC (kkm)
  
  // 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_LM_ARPA_LM_COMPILER_H_
  #define KALDI_LM_ARPA_LM_COMPILER_H_
  
  #include <fst/fstlib.h>
  
  #include "lm/arpa-file-parser.h"
  
  namespace kaldi {
  
  class ArpaLmCompilerImplInterface;
  
  class ArpaLmCompiler : public ArpaFileParser {
   public:
    ArpaLmCompiler(ArpaParseOptions options, int sub_eps,
                   fst::SymbolTable* symbols)
        : ArpaFileParser(options, symbols),
          sub_eps_(sub_eps), impl_(NULL) {
    }
    ~ArpaLmCompiler();
  
    const fst::StdVectorFst& Fst() const { return fst_; }
    fst::StdVectorFst* MutableFst() { return &fst_; }
  
   protected:
    // ArpaFileParser overrides.
    virtual void HeaderAvailable();
    virtual void ConsumeNGram(const NGram& ngram);
    virtual void ReadComplete();
  
  
   private:
    // this function removes states that only have a backoff arc coming
    // out of them.
    void RemoveRedundantStates();
    void Check() const;
  
    int sub_eps_;
    ArpaLmCompilerImplInterface* impl_;  // Owned.
    fst::StdVectorFst fst_;
    template <class HistKey> friend class ArpaLmCompilerImpl;
  };
  
  }  // namespace kaldi
  
  #endif  // KALDI_LM_ARPA_LM_COMPILER_H_