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#ifndef MOZC_BASE_HASH_H_
#define MOZC_BASE_HASH_H_

#include <type_traits>

#include "base/port.h"
#include "base/string_piece.h"

namespace mozc {

class Hash {
 public:
  // Calculates 64-bit fingerprint.
  static uint64 Fingerprint(StringPiece str);
  static uint64 FingerprintWithSeed(StringPiece str, uint32 seed);

  // Calculates 32-bit fingerprint.
  static uint32 Fingerprint32(StringPiece str);
  static uint32 Fingerprint32WithSeed(StringPiece str, uint32 seed);

  // Calculates 64-bit fingerprint for integral types.
  // Note: This function depends on endian.
  template <typename T>
  static typename std::enable_if<std::is_integral<T>::value, uint64>::type
  Fingerprint(T num) {
    return Fingerprint(
        StringPiece(reinterpret_cast<const char*>(&num), sizeof(num)));
  }

  template <typename T>
  static typename std::enable_if<std::is_integral<T>::value, uint64>::type
  FingerprintWithSeed(T num, uint32 seed) {
    return FingerprintWithSeed(
        StringPiece(reinterpret_cast<const char*>(&num), sizeof(num)), seed);
  }

  // Calculates 32-bit fingerprint for integral types.
  // Note: This function depends on endian.
  template <typename T>
  static typename std::enable_if<std::is_integral<T>::value, uint32>::type
  Fingerprint32(T num) {
    return Fingerprint32(
        StringPiece(reinterpret_cast<const char*>(&num), sizeof(num)));
  }

  template <typename T>
  static typename std::enable_if<std::is_integral<T>::value, uint32>::type
  Fingerprint32WithSeed(T num, uint32 seed) {
    return Fingerprint32WithSeed(
        StringPiece(reinterpret_cast<const char*>(&num), sizeof(num)), seed);
  }

 private:
  DISALLOW_IMPLICIT_CONSTRUCTORS(Hash);
};

}  // namespace mozc

#endif  // MOZC_BASE_HASH_H_