VirgilOperationKDF.h

#ifndef VIRGIL_CRYPTO_VIRGIL_KDF_H
#define VIRGIL_CRYPTO_VIRGIL_KDF_H

#include "../VirgilByteArray.h"

#include <memory>

namespace virgil { namespace crypto { inline namespace primitive {

class VirgilOperationKDF {
private:
    template<class Impl>
    struct Model;

public:
    template<class Impl>
    VirgilOperationKDF(Impl impl):self_(std::make_shared<Model<Impl>>(std::move(impl))) {}

    VirgilByteArray derive(
        const VirgilByteArray& keyMaterial, const VirgilByteArray& salt,
        const VirgilByteArray& info, size_t size) const {
        return self_->doDerive(keyMaterial, salt, info, size);
    }

    static VirgilOperationKDF getDefault();

private:
    struct Concept {
        virtual VirgilByteArray doDerive(
            const VirgilByteArray& keyMaterial, const VirgilByteArray& salt,
            const VirgilByteArray& info, size_t size) const = 0;

        virtual ~Concept() noexcept = default;
    };

    template<class Impl>
    struct Model : Concept {

        explicit Model(Impl impl) : impl_(std::move(impl)) {}

        VirgilByteArray doDerive(
            const VirgilByteArray& keyMaterial, const VirgilByteArray& salt,
            const VirgilByteArray& info, size_t size) const override {

            return impl_.derive(keyMaterial, salt, info, size);
        }

    private:
        Impl impl_;
    };

private:
    std::shared_ptr<const Concept> self_;
};

}}}

#endif //VIRGIL_CRYPTO_VIRGIL_KDF_H