// MIT License
//
// Copyright (c) 2020 Advanced Micro Devices, Inc. All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

// CUB's implementation of single_pass_scan_operators has maybe uninitialized
// parameters, disable the warning because all warnings are threated as errors:
#ifdef __HIP_PLATFORM_NVIDIA__
    #pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
#endif

#include "common_benchmark_header.hpp"

// HIP API
#include <hipcub/device/device_reduce.hpp>

#ifndef DEFAULT_N
const size_t DEFAULT_N = 1024 * 1024 * 32;
#endif

const unsigned int batch_size  = 10;
const unsigned int warmup_size = 5;

template<class Key, class Value, class BinaryFunction>
void run_benchmark(benchmark::State& state,
                   size_t            max_length,
                   hipStream_t       stream,
                   size_t            size,
                   BinaryFunction    reduce_op)
{
    using key_type   = Key;
    using value_type = Value;

    // Generate data
    std::vector<key_type> keys_input(size);

    unsigned int        unique_count = 0;
    std::vector<size_t> key_counts
        = benchmark_utils::get_random_data<size_t>(100000, 1, max_length);
    size_t offset = 0;
    while(offset < size)
    {
        const size_t key_count = key_counts[unique_count % key_counts.size()];
        const size_t end       = std::min(size, offset + key_count);
        for(size_t i = offset; i < end; i++)
        {
            keys_input[i] = unique_count;
        }

        unique_count++;
        offset += key_count;
    }

    std::vector<value_type> values_input(size);
    std::iota(values_input.begin(), values_input.end(), 0);

    key_type* d_keys_input;
    HIP_CHECK(hipMalloc(&d_keys_input, size * sizeof(key_type)));
    HIP_CHECK(
        hipMemcpy(d_keys_input, keys_input.data(), size * sizeof(key_type), hipMemcpyHostToDevice));

    value_type* d_values_input;
    HIP_CHECK(hipMalloc(&d_values_input, size * sizeof(value_type)));
    HIP_CHECK(hipMemcpy(d_values_input,
                        values_input.data(),
                        size * sizeof(value_type),
                        hipMemcpyHostToDevice));

    key_type*     d_unique_output;
    value_type*   d_aggregates_output;
    unsigned int* d_unique_count_output;
    HIP_CHECK(hipMalloc(&d_unique_output, unique_count * sizeof(key_type)));
    HIP_CHECK(hipMalloc(&d_aggregates_output, unique_count * sizeof(value_type)));
    HIP_CHECK(hipMalloc(&d_unique_count_output, sizeof(unsigned int)));

    void*  d_temporary_storage     = nullptr;
    size_t temporary_storage_bytes = 0;

    HIP_CHECK(hipcub::DeviceReduce::ReduceByKey(nullptr,
                                                temporary_storage_bytes,
                                                d_keys_input,
                                                d_unique_output,
                                                d_values_input,
                                                d_aggregates_output,
                                                d_unique_count_output,
                                                reduce_op,
                                                size,
                                                stream));

    HIP_CHECK(hipMalloc(&d_temporary_storage, temporary_storage_bytes));
    HIP_CHECK(hipDeviceSynchronize());

    // Warm-up
    for(size_t i = 0; i < warmup_size; i++)
    {
        HIP_CHECK(hipcub::DeviceReduce::ReduceByKey(d_temporary_storage,
                                                    temporary_storage_bytes,
                                                    d_keys_input,
                                                    d_unique_output,
                                                    d_values_input,
                                                    d_aggregates_output,
                                                    d_unique_count_output,
                                                    reduce_op,
                                                    size,
                                                    stream));
    }
    HIP_CHECK(hipDeviceSynchronize());

    for(auto _ : state)
    {
        auto start = std::chrono::high_resolution_clock::now();

        for(size_t i = 0; i < batch_size; i++)
        {
            HIP_CHECK(hipcub::DeviceReduce::ReduceByKey(d_temporary_storage,
                                                        temporary_storage_bytes,
                                                        d_keys_input,
                                                        d_unique_output,
                                                        d_values_input,
                                                        d_aggregates_output,
                                                        d_unique_count_output,
                                                        reduce_op,
                                                        size,
                                                        stream));
        }
        HIP_CHECK(hipStreamSynchronize(stream));

        auto end = std::chrono::high_resolution_clock::now();
        auto elapsed_seconds
            = std::chrono::duration_cast<std::chrono::duration<double>>(end - start);
        state.SetIterationTime(elapsed_seconds.count());
    }
    state.SetBytesProcessed(state.iterations() * batch_size * size
                            * (sizeof(key_type) + sizeof(value_type)));
    state.SetItemsProcessed(state.iterations() * batch_size * size);

    HIP_CHECK(hipFree(d_temporary_storage));
    HIP_CHECK(hipFree(d_keys_input));
    HIP_CHECK(hipFree(d_values_input));
    HIP_CHECK(hipFree(d_unique_output));
    HIP_CHECK(hipFree(d_aggregates_output));
    HIP_CHECK(hipFree(d_unique_count_output));
}

#define CREATE_BENCHMARK(Key, Value, REDUCE_OP)                                                \
    benchmark::RegisterBenchmark(std::string("device_reduce_by_key"                            \
                                             "<key_data_type:" #Key ",value_data_type:" #Value \
                                             ",reduce_op:" #REDUCE_OP ">."                     \
                                             "(random_number_range:[1, "                       \
                                             + std::to_string(max_length) + "])")              \
                                     .c_str(),                                                 \
                                 &run_benchmark<Key, Value, REDUCE_OP>,                        \
                                 max_length,                                                   \
                                 stream,                                                       \
                                 size,                                                         \
                                 REDUCE_OP())

#define CREATE_BENCHMARKS(REDUCE_OP)                                                   \
    CREATE_BENCHMARK(int, float, REDUCE_OP), CREATE_BENCHMARK(int, double, REDUCE_OP), \
        CREATE_BENCHMARK(int, custom_double2, REDUCE_OP),                              \
        CREATE_BENCHMARK(int8_t, int8_t, REDUCE_OP),                                   \
        CREATE_BENCHMARK(long long, float, REDUCE_OP),                                 \
        CREATE_BENCHMARK(long long, double, REDUCE_OP)

void add_benchmarks(size_t                                        max_length,
                    std::vector<benchmark::internal::Benchmark*>& benchmarks,
                    hipStream_t                                   stream,
                    size_t                                        size)
{
    using custom_double2 = benchmark_utils::custom_type<double, double>;

    std::vector<benchmark::internal::Benchmark*> bs = {
        CREATE_BENCHMARKS(hipcub::Sum),
        CREATE_BENCHMARK(long long, custom_double2, hipcub::Sum),
        CREATE_BENCHMARKS(hipcub::Min),
#ifdef HIPCUB_ROCPRIM_API
        CREATE_BENCHMARK(long long, custom_double2, hipcub::Min),
#endif
    };

    benchmarks.insert(benchmarks.end(), bs.begin(), bs.end());
}

int main(int argc, char* argv[])
{
    cli::Parser parser(argc, argv);
    parser.set_optional<size_t>("size", "size", DEFAULT_N, "number of values");
    parser.set_optional<int>("trials", "trials", -1, "number of iterations");
    parser.run_and_exit_if_error();

    // Parse argv
    benchmark::Initialize(&argc, argv);
    const size_t size   = parser.get<size_t>("size");
    const int    trials = parser.get<int>("trials");

    std::cout << "benchmark_device_reduce_by_key" << std::endl;

    // HIP
    hipStream_t     stream = 0; // default
    hipDeviceProp_t devProp;
    int             device_id = 0;
    HIP_CHECK(hipGetDevice(&device_id));
    HIP_CHECK(hipGetDeviceProperties(&devProp, device_id));
    std::cout << "[HIP] Device name: " << devProp.name << std::endl;

    // Add benchmarks
    std::vector<benchmark::internal::Benchmark*> benchmarks;
    add_benchmarks(1000, benchmarks, stream, size);
    add_benchmarks(10, benchmarks, stream, size);

    // Use manual timing
    for(auto& b : benchmarks)
    {
        b->UseManualTime();
        b->Unit(benchmark::kMillisecond);
    }

    // Force number of iterations
    if(trials > 0)
    {
        for(auto& b : benchmarks)
        {
            b->Iterations(trials);
        }
    }

    // Run benchmarks
    benchmark::RunSpecifiedBenchmarks();
    return 0;
}