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#include "rewriter/remove_redundant_candidate_rewriter.h"

#include "converter/segments.h"
#include "protocol/commands.pb.h"
#include "request/conversion_request.h"

namespace mozc {

RemoveRedundantCandidateRewriter::RemoveRedundantCandidateRewriter() {}

RemoveRedundantCandidateRewriter::~RemoveRedundantCandidateRewriter() {}

int RemoveRedundantCandidateRewriter::capability(
    const ConversionRequest &request) const {
  if (request.request().mixed_conversion()) {
    return RewriterInterface::ALL;
  }
  return RewriterInterface::NOT_AVAILABLE;
}

bool RemoveRedundantCandidateRewriter::Rewrite(const ConversionRequest &request,
                                               Segments *segments) const {
  // For mobile, we don't return the single result that is same as a preedit.
  // However we want to have T13N candidates if we have T13N candidates.
  // http://b/5389342
  if (segments->conversion_segments_size() == 1 &&
      segments->conversion_segment(0).candidates_size() == 1 &&
      segments->conversion_segment(0).candidate(0).value ==
          segments->conversion_segment(0).key()) {
    segments->mutable_conversion_segment(0)->clear_candidates();
    return true;
  } else {
    return false;
  }
}
}  // namespace mozc
