// ----------------------------------------------------------------------------
// Copyright 2017 Nervana Systems Inc.
// 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
// ----------------------------------------------------------------------------

#include <fstream>
#include <sstream>

#include <mpi.h>

#include "gtest/gtest.h"

#include "ngraph/file_util.hpp"
#include "ngraph/ngraph.hpp"
#include "ngraph/serializer.hpp"
#include "util/random.hpp"

using namespace std;
using namespace ngraph;

TEST(distributed_${BACKEND_NAME}, allreduce)
{
    auto shape = Shape{2, 2};
    auto A = make_shared<op::Parameter>(element::f32, shape);
    auto f = make_shared<Function>(make_shared<op::AllReduce>(A), op::ParameterVector{A});

    auto manager = runtime::Manager::get("${BACKEND_NAME}");
    auto external = manager->compile(f);
    auto backend = manager->allocate_backend();
    auto cf = backend->make_call_frame(external);

    auto v = vector<float>{1, 2, 3, 4};
    int comm_size;

    MPI_Comm_size(MPI_COMM_WORLD, &comm_size);

    auto a = backend->make_primary_tensor_view(element::f32, shape);
    copy_data(a, vector<float>{1, 2, 3, 4});

    auto result = backend->make_primary_tensor_view(element::f32, shape);

    std::transform(
        v.begin(), v.end(), v.begin(), std::bind1st(std::multiplies<float>(), comm_size));

    cf->call({a}, {result});
    EXPECT_EQ(v, read_vector<float>(result));
}