/*

 * Copyright (C) 2017 - 2018 Intel Corporation.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 * 1. Redistributions of source code must retain the above copyright notice(s),

 *    this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright notice(s),

 *    this list of conditions and the following disclaimer in the documentation

 *    and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO

 * EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE

 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF

 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#pragma once

#include "memory_manager.h"

#include <vector>

#include <random>

class RandomSizesAllocator

{

private:

    std::vector<MemoryManager> allocated_memory;

    memkind_t kind;

    std::default_random_engine generator;

    std::uniform_int_distribution<int> memory_distribution;

    size_t get_random_size()

    {

        return memory_distribution(generator);

    }

public:

    RandomSizesAllocator(memkind_t kind, size_t min_size, size_t max_size,

                         int max_allocations_number) :

        kind(kind),

        memory_distribution(min_size, max_size)

    {

        allocated_memory.reserve(max_allocations_number);

    }

    size_t malloc_random_memory()

    {

        size_t size = get_random_size();

        allocated_memory.emplace_back(kind, size);

        return size;

    }

    size_t free_random_memory()

    {

        if (empty())

            return 0;

        std::uniform_int_distribution<int> distribution(0, allocated_memory.size() - 1);

        int random_index = distribution(generator);

        auto it = std::begin(allocated_memory) + random_index;

        size_t size = it->size();

        allocated_memory.erase(it);

        return size;

    }

    bool empty()

    {

        return allocated_memory.empty();

    }

};