text: // Copyright 2020 Google LLC
  //
  // 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
  //
  //     https://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  //
  
  #ifndef LIBTEXTCLASSIFIER_ANNOTATOR_VOCAB_VOCAB_LEVEL_TABLE_H_
  #define LIBTEXTCLASSIFIER_ANNOTATOR_VOCAB_VOCAB_LEVEL_TABLE_H_
  
  #include "annotator/model_generated.h"
  #include "annotator/types.h"
  #include "utils/container/bit-vector.h"
  #include "marisa-aosp/marisa/trie.h"
  
  namespace libtextclassifier3 {
  
  struct LookupResult {
    // Whether to trigger define for users of beginner proficiency.
    bool beginner_level;
    // Whether if we should avoid triggering define if the leading character is in
    // upper case.
    bool do_not_trigger_in_upper_case;
  };
  
  // A table of vocabs and their levels which is backed by a marisa trie.
  // See http://www.s-yata.jp/marisa-trie/docs/readme.en.html.
  class VocabLevelTable {
   public:
    static std::unique_ptr<VocabLevelTable> Create(const VocabModel* model);
  
    Optional<LookupResult> Lookup(const std::string& vocab) const;
  
   private:
    explicit VocabLevelTable(const VocabModel* model,
                             std::unique_ptr<marisa::Trie> vocab_trie,
                             const BitVector beginner_level,
                             const BitVector do_not_trigger_in_upper_case);
    static const VocabModel* LoadAndVerifyModel();
  
    const VocabModel* model_;
    const std::unique_ptr<marisa::Trie> vocab_trie_;
    const BitVector beginner_level_;
    const BitVector do_not_trigger_in_upper_case_;
  };
  
  }  // namespace libtextclassifier3
  
  #endif  // LIBTEXTCLASSIFIER_ANNOTATOR_VOCAB_VOCAB_LEVEL_TABLE_H_
  