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#ifndef _RGSW_ACC_DM_H_
#define _RGSW_ACC_DM_H_

#include "rgsw-acc.h"

#include <memory>

namespace lbcrypto {

/**
 * @brief Ring GSW accumulator schemes described in
 * https://eprint.iacr.org/2014/816 and https://eprint.iacr.org/2020/086
 */
class RingGSWAccumulatorDM final : public RingGSWAccumulator {
public:
    RingGSWAccumulatorDM() = default;

    /**
   * Key generation for internal Ring GSW as described in https://eprint.iacr.org/2020/086
   *
   * @param params a shared pointer to RingGSW scheme parameters
   * @param skNTT secret key polynomial in the EVALUATION representation
   * @param LWEsk the secret key
   * @return a shared pointer to the resulting keys
   */
    RingGSWACCKey KeyGenAcc(const std::shared_ptr<RingGSWCryptoParams>& params, const NativePoly& skNTT,
                            ConstLWEPrivateKey& LWEsk) const override;

    /**
   * Main accumulator function used in bootstrapping - AP variant
   *
   * @param params a shared pointer to RingGSW scheme parameters
   * @param ek the accumulator key
   * @param acc previous value of the accumulator
   * @param a value to update the accumulator with
   */
    void EvalAcc(const std::shared_ptr<RingGSWCryptoParams>& params, ConstRingGSWACCKey& ek, RLWECiphertext& acc,
                 const NativeVector& a) const override;

private:
    /**
   * DM Key generation for internal Ring GSW as described in https://eprint.iacr.org/2014/816
   *
   * @param params a shared pointer to RingGSW scheme parameters
   * @param skNTT secret key polynomial in the EVALUATION representation
   * @param m a plaintext
   * @return a shared pointer to the resulting keys
   */
    RingGSWEvalKey KeyGenDM(const std::shared_ptr<RingGSWCryptoParams>& params, const NativePoly& skNTT,
                            LWEPlaintext m) const;

    /**
   * DM Accumulation as described in https://eprint.iacr.org/2020/086
   *
   * @param params a shared pointer to RingGSW scheme parameters
   * @param ek evaluation key for Ring GSW
   * @param acc previous value of the accumulator
   * @return
   */
    void AddToAccDM(const std::shared_ptr<RingGSWCryptoParams>& params, ConstRingGSWEvalKey& ek,
                    RLWECiphertext& acc) const;
};

}  // namespace lbcrypto

#endif  // _RGSW_ACC_DM_H_
