/* ************************************************************************
 * Copyright 2018-2022 Advanced Micro Devices, Inc.
 * ************************************************************************ */

#pragma once

#include "rocblas.h"
#include "rocblas_init.hpp"
#include "rocblas_test.hpp"
#include "singletons.hpp"
#include <cinttypes>

#define MEM_MAX_GUARD_PAD 8192

/* ============================================================================================ */
/*! \brief  base-class to allocate/deallocate device memory */
template <typename T>
class d_vector
{
private:
    size_t m_size;
    size_t m_pad, m_guard_len;
    size_t m_bytes;

    static bool m_init_guard;

protected:
    inline size_t nmemb() const noexcept
    {
        return m_size;
    }

public:
    bool use_HMM = false;

public:
    static T m_guard[MEM_MAX_GUARD_PAD];

#ifdef GOOGLE_TEST
    d_vector(size_t s, bool HMM = false)
        : m_size(s)
        , m_pad(std::min(g_DVEC_PAD, size_t(MEM_MAX_GUARD_PAD)))
        , m_guard_len(m_pad * sizeof(T))
        , m_bytes((s + m_pad * 2) * sizeof(T))
        , use_HMM(HMM)
    {
        // Initialize m_guard with random data
        if(!m_init_guard)
        {
            rocblas_init_nan(m_guard, MEM_MAX_GUARD_PAD);
            m_init_guard = true;
        }
    }
#else
    d_vector(size_t s, bool HMM = false)
        : m_size(s)
        , m_pad(0) // save current pad length
        , m_guard_len(0 * sizeof(T))
        , m_bytes(s ? s * sizeof(T) : sizeof(T))
        , use_HMM(HMM)
    {
    }
#endif

    T* device_vector_setup()
    {
        T* d = nullptr;
        if(use_HMM ? hipMallocManaged(&d, m_bytes) : (hipMalloc)(&d, m_bytes) != hipSuccess)
        {
            rocblas_cerr << "Warning: hip can't allocate " << m_bytes << " bytes ("
                         << (m_bytes >> 30) << " GB)" << std::endl;

            d = nullptr;
        }
#ifdef GOOGLE_TEST
        else
        {
            if(m_guard_len > 0)
            {
                // Copy m_guard to device memory before allocated memory
                hipMemcpy(d, m_guard, m_guard_len, hipMemcpyHostToDevice);

                // Point to allocated block
                d += m_pad;

                // Copy m_guard to device memory after allocated memory
                hipMemcpy(d + m_size, m_guard, m_guard_len, hipMemcpyHostToDevice);
            }
        }
#endif
        return d;
    }

    void device_vector_check(T* d)
    {
#ifdef GOOGLE_TEST
        if(m_guard_len > 0)
        {
            T host[m_pad];

            // Copy device memory after allocated memory to host
            hipMemcpy(host, d + this->m_size, m_guard_len, hipMemcpyDeviceToHost);

            // Make sure no corruption has occurred
            EXPECT_EQ(memcmp(host, m_guard, m_guard_len), 0);

            // Point to m_guard before allocated memory
            d -= m_pad;

            // Copy device memory after allocated memory to host
            hipMemcpy(host, d, m_guard_len, hipMemcpyDeviceToHost);

            // Make sure no corruption has occurred
            EXPECT_EQ(memcmp(host, m_guard, m_guard_len), 0);
        }
#endif
    }

    void device_vector_teardown(T* d)
    {
        if(d != nullptr)
        {
#ifdef GOOGLE_TEST
            if(m_pad > 0)
            {
                T host[m_pad];

                // Copy device memory after allocated memory to host
                hipMemcpy(host, d + this->m_size, m_guard_len, hipMemcpyDeviceToHost);

                // Make sure no corruption has occurred
                EXPECT_EQ(memcmp(host, m_guard, m_guard_len), 0);

                // Point to m_guard before allocated memory
                d -= m_pad;

                // Copy device memory after allocated memory to host
                hipMemcpy(host, d, m_guard_len, hipMemcpyDeviceToHost);

                // Make sure no corruption has occurred
                EXPECT_EQ(memcmp(host, m_guard, m_guard_len), 0);
            }
#endif
            // Free device memory
            CHECK_HIP_ERROR((hipFree)(d));
        }
    }
};

template <typename T>
T d_vector<T>::m_guard[MEM_MAX_GUARD_PAD] = {};

template <typename T>
bool d_vector<T>::m_init_guard = false;

#undef MEM_MAX_GUARD_PAD