#include "common.h"

constexpr size_t THREADS_NO    = std::min(max_no_threads, 8);
constexpr size_t key_range     = 1e4;
constexpr size_t op_per_thread = 1e5;
// Depending on value there is a possiblity of numerical overflow
constexpr size_t max_number               = 10;
constexpr size_t no_insert_for_one_delete = 1;

/**
 * This test checks MultiIterator remove method.
 * Each thread removes random data. So removes are joint and scattered on same
 * key values. Calls of remove method are interleaved with insert calls which
 * always succeed.
 */
int main()
{
    init_log();

    memory_check(THREADS_NO, [] {
        multimap_t skiplist;

        auto futures = run<std::pair<long long, std::vector<long long>>>(
            THREADS_NO, skiplist, [](auto acc, auto index) {
                auto rand           = rand_gen(key_range);
                auto rand_op        = rand_gen_bool(no_insert_for_one_delete);
                long long downcount = op_per_thread;
                std::vector<long long> set(key_range, 0);
                long long sum = 0;

                do
                {
                    size_t num = rand();
                    auto data  = rand() % max_number;
                    if (rand_op())
                    {

                        int len = 0;
                        for (auto it = acc.find_multi(num); it.has_value();
                             it++)
                        {
                            len++;
                        }
                        if (len > 0)
                        {
                            int pos = rand() % len;
                            for (auto it = acc.find_multi(num); it.has_value();
                                 it++)
                            {
                                if (pos == 0)
                                {
                                    auto data_r = it->second;
                                    if (it.remove())
                                    {
                                        downcount--;
                                        set[num]--;
                                        sum -= data_r;
                                        permanent_assert(
                                            it.is_removed(),
                                            "is_removed method doesn't work");
                                    }
                                    break;
                                }
                                pos--;
                            }
                        }
                    }
                    else
                    {
                        acc.insert(num, data);
                        downcount--;
                        set[num]++;
                        sum += data;
                    }
                } while (downcount > 0);

                return std::pair<long long, std::vector<long long>>(sum, set);
            });

        long set[key_range] = {0};
        long long sums      = 0;
        for (auto &data : collect(futures))
        {
            sums += data.second.first;
            for (int i = 0; i < key_range; i++)
            {
                set[i] += data.second.second[i];
            }
        }

        auto accessor = skiplist.access();
        check_multi_iterator(accessor, key_range, set);

        for (auto &e : accessor)
        {
            set[e.first]--;
            sums -= e.second;
        }
        permanent_assert(sums == 0, "Aproximetly Same values are present");

        check_zero(key_range, set, "MultiMap");

        check_order<multimap_t>(accessor);
    });
}