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#include "prediction/suggestion_filter.h"

#include "base/base.h"
#include "base/singleton.h"
#include "base/util.h"
#include "storage/existence_filter.h"

namespace mozc {
namespace {

#include "prediction/suggestion_filter_data.h"

class SuggestionFilterImpl {
 public:
  bool IsBadSuggestion(const string &text) const {
    if (filter_.get() == NULL) {
      return false;
    }
    string lower_text = text;
    Util::LowerString(&lower_text);
    return filter_->Exists(Util::Fingerprint(lower_text.data(),
                                             lower_text.size()));
  }

  SuggestionFilterImpl() : filter_(NULL) {
    // kSuggestionFilterData_data and kSuggestionFilterData_size
    // are defined in suggest_filter_data.h
    filter_.reset(ExistenceFilter::Read(kSuggestionFilterData_data,
                                        kSuggestionFilterData_size));
    LOG_IF(ERROR, filter_.get() == NULL)
        << "SuggestionFilterData is broken";
  }

 private:
  scoped_ptr<ExistenceFilter> filter_;
};
}  // namespace

bool SuggestionFilter::IsBadSuggestion(const string &text) {
  return Singleton<SuggestionFilterImpl>::get()->IsBadSuggestion(text);
}
}  // namespace mozc