/*******************************************************************************
 * Copyright (c) 2015-2018 Skymind, Inc.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Apache License, Version 2.0 which is available at
 * https://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 limitations
 * under the License.
 *
 * SPDX-License-Identifier: Apache-2.0
 ******************************************************************************/

//
// @author saudet
// @author raver119@gmail.com
//

#include <ops/declarable/PlatformHelper.h>
#include <ops/declarable/OpRegistrator.h>
#include <platform_boilerplate.h>

#include <helpers/MKLDNNStream.h>
#include "mkldnnUtils.h"
#include <ops/declarable/helpers/convolutions.h>

using namespace mkldnn;

namespace nd4j {
    namespace ops {
        namespace platforms {
            PLATFORM_IMPL(conv3dnew_bp) {
                auto input = INPUT_VARIABLE(
                        0);                                                // [bS, iD, iH, iW, iC] (NDHWC) or [bS, iC, iD, iH, iW] (NCDHW)
                auto weights = INPUT_VARIABLE(
                        1);                                                // [kD, kH, kW, iC, oC] always
                auto bias = block.width() > 3 ? INPUT_VARIABLE(2) : nullptr;                  // [oC]
                auto gradO = block.width() > 3 ? INPUT_VARIABLE(3) : INPUT_VARIABLE(
                        2);        // [bS, oD, oH, oW, oC] (NDHWC) or [bS, oC, oD, oH, oW] (NCDHW), epsilon_next

                auto gradI = OUTPUT_VARIABLE(
                        0);                                                 // [bS, iD, iH, iW, iC] (NDHWC) or [bS, iC, iD, iH, iW] (NCDHW), epsilon
                auto gradW = OUTPUT_VARIABLE(
                        1);                                                 // [kD, kH, kW, iC, oC] always
                auto gradB = block.width() > 3 ? OUTPUT_VARIABLE(2) : nullptr;                   // [oC]

                REQUIRE_TRUE(input->rankOf() == 5, 0,
                             "CUSTOM CONV3D_BP OP: rank of input array must be equal to 5, but got %i instead !",
                             input->rankOf());
                REQUIRE_TRUE(weights->rankOf() == 5, 0,
                             "CUSTOM CONV3D_BP OP: rank of weights array must be equal to 5, but got %i instead !",
                             weights->rankOf());
                REQUIRE_TRUE(gradO->rankOf() == 5, 0,
                             "CUSTOM CONV3D_BP OP: rank of output gradients (next epsilon) array must be equal to 5, but got %i instead !",
                             gradO->rankOf());

                int kD = INT_ARG(0) > 0 ? INT_ARG(0) : static_cast<int>(weights->sizeAt(0));// filter(kernel) depth
                int kH = INT_ARG(1) > 0 ? INT_ARG(1) : static_cast<int>(weights->sizeAt(1));// filter(kernel) height
                int kW = INT_ARG(2) > 0 ? INT_ARG(2) : static_cast<int>(weights->sizeAt(2));// filter(kernel) width
                int sD = INT_ARG(3);                                                        // strides depth
                int sH = INT_ARG(4);                                                        // strides height
                int sW = INT_ARG(5);                                                        // strides width
                int pD = INT_ARG(6);                                                        // paddings depth
                int pH = INT_ARG(7);                                                        // paddings height
                int pW = INT_ARG(8);                                                        // paddings width
                int dD = INT_ARG(9);                                                        // dilations depth
                int dH = INT_ARG(10);                                                       // dilations height
                int dW = INT_ARG(11);                                                       // dilations width
                int isSameMode = INT_ARG(12);                                               // 1-SAME,  0-VALID
                int isNDHWC =
                        block.getIArguments()->size() > 13 ? !INT_ARG(13) : 1;       // INT_ARG(13): 1-NDHWC, 0-NCDHW

                int bS, iC, iD, iH, iW, oC, oD, oH, oW;                     // batch size, input channels, input depth/height/width, output channels, output depth/height/width;
                int indIOioC, indIOioD, indWoC, indWiC, indWkD;             // corresponding indexes
                ConvolutionUtils::getSizesAndIndexesConv3d(isNDHWC, *input, *gradO, bS, iC, iD, iH, iW, oC, oD, oH, oW,
                                                           indIOioC, indIOioD, indWiC, indWoC, indWkD);

                int trueoD, trueoH, trueoW;          // true output depth/height/width
                ConvolutionUtils::calcOutSizePool3D(trueoD, trueoH, trueoW, kD, kH, kW, sD, sH, sW, pD, pH, pW, dD, dH,
                                                    dW, iD, iH, iW, isSameMode);

                std::string expectedGradOShape = ShapeUtils::shapeAsString(ShapeUtils::composeShapeUsingDimsAndIdx(
                        {bS, oC, trueoD, trueoH, trueoW, 0, indIOioC, indIOioD, indIOioD + 1, indIOioD + 2}));
                std::string expectedWeightsShape = ShapeUtils::shapeAsString({kD, kH, kW, iC, oC});
                REQUIRE_TRUE(expectedGradOShape == ShapeUtils::shapeAsString(gradO), 0,
                             "CUSTOM CONV3D_BP OP: wrong shape of output gradients (next epsilon) array, expected is %s, but got %s instead !",
                             expectedGradOShape.c_str(), ShapeUtils::shapeAsString(gradO).c_str());
                REQUIRE_TRUE(expectedWeightsShape == ShapeUtils::shapeAsString(weights), 0,
                             "CUSTOM CONV3D_BP OP: wrong shape of weights array, expected is %s, but got %s instead !",
                             expectedWeightsShape.c_str(), ShapeUtils::shapeAsString(weights).c_str());
                if (bias)
                    REQUIRE_TRUE(bias->rankOf() <= 2 && oC == bias->lengthOf(), 0,
                                 "CUSTOM CONV3D_BP OP: wrong shape of array with biases, expected rank, length: <=2, %i, but got %i, %i instead !",
                                 oC, bias->rankOf(), bias->lengthOf());


                mkldnn_memory_desc_t empty;
                mkldnn::memory::desc conv_src_md(empty), conv_diff_src_md(empty), conv_weights_md(empty),
                        conv_diff_weights_md(empty), conv_bias_md(empty), conv_dst_md(empty);
                mkldnn::memory::desc user_src_md(empty), user_diff_src_md(empty), user_weights_md(empty),
                        user_diff_weights_md(empty), user_bias_md(empty), user_dst_md(empty);
                mkldnn::memory::dims conv_strides, conv_padding, conv_padding_r;
                mkldnnUtils::getMKLDNNMemoryDescConv3d(kD, kH, kW, sD, sH, sW, pD, pH, pW, dD, dH, dW, isSameMode,
                                                       isNDHWC,
                                                       bS, iC, iD, iH, iW, oC, oD, oH, oW, input, gradI, weights,
                                                       gradW, gradB, gradO,
                                                       &conv_src_md, &conv_diff_src_md, &conv_weights_md,
                                                       &conv_diff_weights_md, &conv_bias_md, &conv_dst_md,
                                                       &user_src_md, &user_diff_src_md, &user_weights_md,
                                                       &user_diff_weights_md, &user_bias_md, &user_dst_md,
                                                       conv_strides, conv_padding, conv_padding_r);
                auto conv_desc = gradB != nullptr
                                 ? convolution_forward::desc(prop_kind::forward,
                                                             algorithm::convolution_auto, conv_src_md,
                                                             conv_weights_md, conv_bias_md,
                                                             conv_dst_md, conv_strides, conv_padding,
                                                             conv_padding_r)
                                 : convolution_forward::desc(prop_kind::forward,
                                                             algorithm::convolution_auto, conv_src_md,
                                                             conv_weights_md,
                                                             conv_dst_md, conv_strides, conv_padding,
                                                             conv_padding_r);
                auto conv_prim_desc = convolution_forward::primitive_desc(conv_desc, mkldnnUtils::getEngine(
                        LaunchContext::defaultContext()->engine()));
                if (gradW != nullptr) {
                    auto convW_desc = gradB != nullptr
                                      ? convolution_backward_weights::desc(
                                    algorithm::convolution_auto, conv_src_md, conv_diff_weights_md, conv_bias_md,
                                    conv_dst_md, conv_strides, conv_padding, conv_padding_r)
                                      : convolution_backward_weights::desc(
                                    algorithm::convolution_auto, conv_src_md, conv_diff_weights_md,
                                    conv_dst_md, conv_strides, conv_padding, conv_padding_r);

                    auto engine = mkldnnUtils::getEngine(LaunchContext::defaultContext()->engine());
                    mkldnn::stream stream(engine);
                    auto convW_prim_desc = convolution_backward_weights::primitive_desc(convW_desc, engine,
                                                                                        conv_prim_desc);
                    auto userW_src_memory = mkldnn::memory(user_src_md, engine,
                                                           const_cast<NDArray *>(input)->buffer());
                    auto userW_weights_memory = mkldnn::memory(user_diff_weights_md, engine, gradW->buffer());
                    auto userW_dst_memory = mkldnn::memory(user_dst_md, engine,
                                                           const_cast<NDArray *>(gradO)->buffer());

                    auto convW_src_memory = userW_src_memory;
                    if (convW_prim_desc.src_desc() != userW_src_memory.get_desc()) {
                        convW_src_memory = mkldnn::memory(convW_prim_desc.src_desc(), engine);
                        reorder(userW_src_memory, convW_src_memory).execute(stream, userW_src_memory,
                                                                            convW_src_memory);
                    }

                    auto convW_weights_memory = userW_weights_memory;
                    if (convW_prim_desc.diff_weights_desc() != userW_weights_memory.get_desc()) {
                        convW_weights_memory = mkldnn::memory(convW_prim_desc.diff_weights_desc(), engine);
                    }

                    auto convW_dst_memory = userW_dst_memory;
                    if (convW_prim_desc.diff_dst_desc() != userW_dst_memory.get_desc()) {
                        convW_dst_memory = mkldnn::memory(convW_prim_desc.diff_dst_desc(), engine);
                        reorder(userW_dst_memory, convW_dst_memory).execute(stream, userW_dst_memory,
                                                                            convW_dst_memory);
                    }

                    if (gradB != nullptr) {
                        auto convW_bias_memory = mkldnn::memory(convW_prim_desc.diff_bias_desc(), engine,
                                                                gradB->buffer());
                        convolution_backward_weights(convW_prim_desc).execute(stream,
                                                                              {{MKLDNN_ARG_SRC,          convW_src_memory},
                                                                               {MKLDNN_ARG_DIFF_DST,     convW_dst_memory},
                                                                               {MKLDNN_ARG_DIFF_WEIGHTS, convW_weights_memory},
                                                                               {MKLDNN_ARG_DIFF_BIAS,    convW_bias_memory}});
                    } else {
                        convolution_backward_weights(convW_prim_desc).execute(stream,
                                                                              {{MKLDNN_ARG_SRC,          convW_src_memory},
                                                                               {MKLDNN_ARG_DIFF_DST,     convW_dst_memory},
                                                                               {MKLDNN_ARG_DIFF_WEIGHTS, convW_weights_memory}});
                    }

                    if (convW_prim_desc.diff_weights_desc() != userW_weights_memory.get_desc()) {
                        reorder(convW_weights_memory, userW_weights_memory).execute(stream, convW_weights_memory,
                                                                                    userW_weights_memory);
                    }

                    stream.wait();
                }
                if (gradI != nullptr) {
                    auto convI_desc = convolution_backward_data::desc(algorithm::convolution_auto,
                                                                      conv_diff_src_md, conv_weights_md,
                                                                      conv_dst_md, conv_strides, conv_padding,
                                                                      conv_padding_r);

                    auto engine = mkldnnUtils::getEngine(LaunchContext::defaultContext()->engine());
                    mkldnn::stream stream(engine);
                    auto convI_prim_desc = convolution_backward_data::primitive_desc(convI_desc, engine,
                                                                                     conv_prim_desc);
                    auto userI_src_memory = mkldnn::memory(user_diff_src_md, engine, gradI->buffer());
                    auto userI_weights_memory = mkldnn::memory(user_weights_md, engine,
                                                               const_cast<NDArray *>(weights)->buffer());
                    auto userI_dst_memory = mkldnn::memory(user_dst_md, engine,
                                                           const_cast<NDArray *>(gradO)->buffer());

                    auto convI_src_memory = userI_src_memory;
                    if (convI_prim_desc.diff_src_desc() != userI_src_memory.get_desc()) {
                        convI_src_memory = mkldnn::memory(convI_prim_desc.diff_src_desc(), engine);
                    }

                    auto convI_weights_memory = userI_weights_memory;
                    if (convI_prim_desc.weights_desc() != userI_weights_memory.get_desc()) {
                        convI_weights_memory = mkldnn::memory(convI_prim_desc.weights_desc(), engine);
                        reorder(userI_weights_memory, convI_weights_memory).execute(stream, userI_weights_memory,
                                                                                    convI_weights_memory);
                    }

                    auto convI_dst_memory = userI_dst_memory;
                    if (convI_prim_desc.diff_dst_desc() != userI_dst_memory.get_desc()) {
                        convI_dst_memory = mkldnn::memory(convI_prim_desc.diff_dst_desc(), engine);
                        reorder(userI_dst_memory, convI_dst_memory).execute(stream, userI_dst_memory,
                                                                            convI_dst_memory);
                    }

                    convolution_backward_data(convI_prim_desc).execute(stream,
                                                                       {{MKLDNN_ARG_DIFF_DST, convI_dst_memory},
                                                                        {MKLDNN_ARG_WEIGHTS,  convI_weights_memory},
                                                                        {MKLDNN_ARG_DIFF_SRC, convI_src_memory}});

                    if (convI_prim_desc.diff_src_desc() != userI_src_memory.get_desc()) {
                        reorder(convI_src_memory, userI_src_memory).execute(stream, convI_src_memory,
                                                                            userI_src_memory);
                    }

                    stream.wait();
                }

                return Status::OK();
            }

            PLATFORM_CHECK(conv3dnew_bp) {
                // we don't want to use mkldnn if cpu doesn't support avx/avx2
                if (::optimalLevel() < 2)
                    return false;

                auto input = INPUT_VARIABLE(
                        0);                                                // [bS, iD, iH, iW, iC] (NDHWC) or [bS, iC, iD, iH, iW] (NCDHW)
                auto weights = INPUT_VARIABLE(
                        1);                                                // [kD, kH, kW, iC, oC] always
                auto bias = block.width() > 3 ? INPUT_VARIABLE(2) : nullptr;                  // [oC]
                auto gradO = block.width() > 3 ? INPUT_VARIABLE(3) : INPUT_VARIABLE(
                        2);        // [bS, oD, oH, oW, oC] (NDHWC) or [bS, oC, oD, oH, oW] (NCDHW), epsilon_next

                auto gradI = OUTPUT_VARIABLE(
                        0);                                                 // [bS, iD, iH, iW, iC] (NDHWC) or [bS, iC, iD, iH, iW] (NCDHW), epsilon
                auto gradW = OUTPUT_VARIABLE(
                        1);                                                 // [kD, kH, kW, iC, oC] always
                auto gradB = block.width() > 3 ? OUTPUT_VARIABLE(2) : nullptr;                   // [oC]

                return block.isUseMKLDNN() &&
                       nd4j::MKLDNNStream::isSupported({input, weights, bias, gradO, gradI, gradW, gradB});
            }
        }
    }
}