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#include "rewriter/normalization_rewriter.h"

#include <string>
#include <vector>

#include "base/logging.h"
#include "base/text_normalizer.h"
#include "base/util.h"
#include "converter/segments.h"
#include "request/conversion_request.h"

namespace mozc {
namespace {

enum CandidateType { CANDIDATE, TRANSLITERATION };

bool NormalizeCandidate(Segment::Candidate *candidate, CandidateType type) {
  DCHECK(candidate);
  if (candidate->attributes & Segment::Candidate::USER_DICTIONARY) {
    return false;
  }

  std::string value, content_value;
  switch (type) {
    case CANDIDATE:  // Go through to TRANSLITERATION
    case TRANSLITERATION:
      TextNormalizer::NormalizeText(candidate->value, &value);
      TextNormalizer::NormalizeText(candidate->content_value, &content_value);
      break;
    default:
      LOG(ERROR) << "unknown type";
      return false;
  }

  const bool modified =
      (content_value != candidate->content_value || value != candidate->value);
  candidate->value = value;
  candidate->content_value = content_value;

  return modified;
}
}  // namespace

NormalizationRewriter::NormalizationRewriter() {}

NormalizationRewriter::~NormalizationRewriter() {}

int NormalizationRewriter::capability(const ConversionRequest &request) const {
  return RewriterInterface::ALL;
}

bool NormalizationRewriter::Rewrite(const ConversionRequest &request,
                                    Segments *segments) const {
  DCHECK(segments);

  bool modified = false;
  for (size_t i = 0; i < segments->conversion_segments_size(); ++i) {
    Segment *segment = segments->mutable_conversion_segment(i);
    DCHECK(segment);

    // Meta candidate
    for (size_t j = 0; j < segment->meta_candidates_size(); ++j) {
      Segment::Candidate *candidate =
          segment->mutable_candidate(-static_cast<int>(j) - 1);
      DCHECK(candidate);
      modified |= NormalizeCandidate(candidate, TRANSLITERATION);
    }

    // Regular candidate.
    for (size_t j = 0; j < segment->candidates_size(); ++j) {
      Segment::Candidate *candidate = segment->mutable_candidate(j);
      DCHECK(candidate);
      modified |= NormalizeCandidate(candidate, CANDIDATE);
    }
  }

  return modified;
}
}  // namespace mozc
