/*
 * Copyright (c) 2021-2023, NVIDIA CORPORATION. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#pragma once

#include <cassert>
#include <cstring>
#include <type_traits>
#include <vector>

#include <iostream>
using std::cerr;
using std::cout;
using std::endl;

template<typename T>
inline void serialize_value(void** buffer, T const& value);

template<typename T>
inline void deserialize_value(void const** buffer, size_t* buffer_size, T* value);

namespace {

template<typename T, class Enable = void>
struct Serializer {
};

template<typename T>
struct Serializer<
    T,
    typename std::enable_if<std::is_arithmetic<T>::value || std::is_enum<T>::value || std::is_pod<T>::value>::type> {
    static size_t serialized_size(T const& value)
    {
        return sizeof(T);
    }
    static void serialize(void** buffer, T const& value)
    {
        ::memcpy(*buffer, &value, sizeof(T));
        reinterpret_cast<char*&>(*buffer) += sizeof(T);
    }
    static void deserialize(void const** buffer, size_t* buffer_size, T* value)
    {
        assert(*buffer_size >= sizeof(T));
        ::memcpy(value, *buffer, sizeof(T));
        reinterpret_cast<char const*&>(*buffer) += sizeof(T);
        *buffer_size -= sizeof(T);
    }
};

template<>
struct Serializer<const char*> {
    static size_t serialized_size(const char* value)
    {
        return strlen(value) + 1;
    }
    static void serialize(void** buffer, const char* value)
    {
        ::strcpy(static_cast<char*>(*buffer), value);
        reinterpret_cast<char*&>(*buffer) += strlen(value) + 1;
    }
    static void deserialize(void const** buffer, size_t* buffer_size, const char** value)
    {
        *value           = static_cast<char const*>(*buffer);
        size_t data_size = strnlen(*value, *buffer_size) + 1;
        assert(*buffer_size >= data_size);
        reinterpret_cast<char const*&>(*buffer) += data_size;
        *buffer_size -= data_size;
    }
};

template<typename T>
struct Serializer<
    std::vector<T>,
    typename std::enable_if<std::is_arithmetic<T>::value || std::is_enum<T>::value || std::is_pod<T>::value>::type> {
    static size_t serialized_size(std::vector<T> const& value)
    {
        return sizeof(value.size()) + value.size() * sizeof(T);
    }
    static void serialize(void** buffer, std::vector<T> const& value)
    {
        serialize_value(buffer, value.size());
        size_t nbyte = value.size() * sizeof(T);
        ::memcpy(*buffer, value.data(), nbyte);
        reinterpret_cast<char*&>(*buffer) += nbyte;
    }
    static void deserialize(void const** buffer, size_t* buffer_size, std::vector<T>* value)
    {
        size_t size;
        deserialize_value(buffer, buffer_size, &size);
        value->resize(size);
        size_t nbyte = value->size() * sizeof(T);
        assert(*buffer_size >= nbyte);
        ::memcpy(value->data(), *buffer, nbyte);
        reinterpret_cast<char const*&>(*buffer) += nbyte;
        *buffer_size -= nbyte;
    }
};

}  // namespace

template<typename T>
inline size_t serialized_size(T const& value)
{
    return Serializer<T>::serialized_size(value);
}

template<typename T>
inline void serialize_value(void** buffer, T const& value)
{
    return Serializer<T>::serialize(buffer, value);
}

template<typename T>
inline void deserialize_value(void const** buffer, size_t* buffer_size, T* value)
{
    return Serializer<T>::deserialize(buffer, buffer_size, value);
}
