// Copyright 2018 Xiaomi, Inc.  All rights reserved.
//
// 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
// limitations under the License.
#ifndef MACE_OPS_OPENCL_IMAGE_POOLING_H_
#define MACE_OPS_OPENCL_IMAGE_POOLING_H_

#include "mace/ops/opencl/pooling.h"

#include <algorithm>
#include <memory>
#include <vector>
#include <set>
#include <string>

#include "mace/core/op_context.h"
#include "mace/core/tensor.h"
#include "mace/ops/opencl/helper.h"

namespace mace {
namespace ops {
namespace opencl {
namespace image {
namespace pooling {
inline std::vector<uint32_t> LocalWS(OpenCLRuntime *runtime,
                                     const uint32_t *gws,
                                     const uint32_t kwg_size) {
  std::vector<uint32_t> lws(4, 0);
  if (kwg_size == 0) {
    lws[0] = lws[1] = lws[2] = 1;
  } else {
    uint64_t
        cache_size = runtime->device_global_mem_cache_size();
    uint32_t base = std::max<uint32_t>(cache_size / kBaseGPUMemCacheSize, 1);
    lws[1] = std::min<uint32_t>(gws[1], kwg_size);
    lws[2] =
        std::min<uint32_t>(std::min<uint32_t>(gws[2], base), kwg_size / lws[1]);
    const uint32_t lws_size = lws[1] * lws[2];
    lws[0] = gws[0] / 4;
    if (lws[0] == 0) {
      lws[0] = gws[0];
    }
    lws[0] = std::max<uint32_t>(std::min<uint32_t>(lws[0], kwg_size / lws_size),
                                1);
  }
  return lws;
}
}  // namespace pooling


template <typename T>
class PoolingKernel : public OpenCLPoolingKernel {
 public:
  MaceStatus Compute(
      OpContext *context,
      const Tensor *input,
      const PoolingType pooling_type,
      const int *kernels,
      const int *strides,
      const Padding &padding_type,
      const std::vector<int> &padding_data,
      const int *dilations,
      Tensor *output) override;

 private:
  cl::Kernel kernel_;
  uint32_t kwg_size_;
  std::vector<index_t> input_shape_;
};

template <typename T>
MaceStatus PoolingKernel<T>::Compute(
    OpContext *context,
    const Tensor *input,
    const PoolingType pooling_type,
    const int *kernels,
    const int *strides,
    const Padding &padding_type,
    const std::vector<int> &padding_data,
    const int *dilations,
    Tensor *output) {
  MACE_CHECK(dilations[0] == 1 && dilations[1] == 1)
    << "Pooling opencl kernel not support dilation yet";

  std::vector<index_t> output_shape(4);
  std::vector<index_t> filter_shape = {input->dim(3), input->dim(3),
                                       kernels[0], kernels[1]};

  std::vector<int> paddings(2);
  if (padding_data.empty()) {
    ops::CalcNHWCPaddingAndOutputSize(
        input->shape().data(), filter_shape.data(), dilations, strides,
        padding_type, output_shape.data(), paddings.data());
  } else {
    paddings = padding_data;
    CalcOutputSize(input->shape().data(), filter_shape.data(),
                   padding_data.data(), dilations, strides, RoundType::CEIL,
                   output_shape.data());
  }

  std::vector<size_t> output_image_shape;
  CalImage2DShape(output_shape, BufferType::IN_OUT_CHANNEL,
                  &output_image_shape);
  MACE_RETURN_IF_ERROR(output->ResizeImage(output_shape, output_image_shape));

  auto runtime = context->device()->opencl_runtime();
  MACE_OUT_OF_RANGE_DEFINITION;

  if (kernel_.get() == nullptr) {
    const DataType dt = DataTypeToEnum<T>::value;
    std::set<std::string> built_options;
    MACE_OUT_OF_RANGE_CONFIG;
    MACE_NON_UNIFORM_WG_CONFIG;
    std::string kernel_name = MACE_OBFUSCATE_SYMBOL("pooling");
    built_options.emplace("-Dpooling=" + kernel_name);

    if (pooling_type == MAX && input->dtype() == output->dtype()) {
      built_options.emplace("-DDATA_TYPE=" + DtToCLDt(dt));
      built_options.emplace("-DCMD_DATA_TYPE=" + DtToCLCMDDt(dt));
    } else {
      built_options.emplace("-DDATA_TYPE=" + DtToUpCompatibleCLDt(dt));
      built_options.emplace("-DCMD_DATA_TYPE=" + DtToUpCompatibleCLCMDDt(dt));
    }
    if (pooling_type == AVG) {
      built_options.emplace("-DPOOL_AVG");
    }
    MACE_RETURN_IF_ERROR(runtime->BuildKernel("pooling",
                                              kernel_name,
                                              built_options,
                                              &kernel_));

    kwg_size_ =
        static_cast<uint32_t>(runtime->GetKernelMaxWorkGroupSize(kernel_));
  }

  const uint32_t gws[3] = {
      static_cast<uint32_t>(RoundUpDiv4(output->dim(3))),
      static_cast<uint32_t>(output->dim(2)),
      static_cast<uint32_t>(output->dim(0) * output->dim(1)),
  };
  MACE_OUT_OF_RANGE_INIT(kernel_);

  if (!IsVecEqual(input_shape_, input->shape())) {
    uint32_t idx = 0;
    MACE_OUT_OF_RANGE_SET_ARGS(kernel_);
    MACE_SET_3D_GWS_ARGS(kernel_, gws);
    kernel_.setArg(idx++, *(input->opencl_image()));
    kernel_.setArg(idx++, static_cast<int32_t>(input->dim(1)));
    kernel_.setArg(idx++, static_cast<int32_t>(input->dim(2)));
    kernel_.setArg(idx++, static_cast<int32_t>(output->dim(1)));
    kernel_.setArg(idx++, paddings[0] / 2);
    kernel_.setArg(idx++, paddings[1] / 2);
    kernel_.setArg(idx++, strides[0]);
    kernel_.setArg(idx++, strides[1]);
    kernel_.setArg(idx++, kernels[0]);
    kernel_.setArg(idx++, kernels[1]);
    kernel_.setArg(idx++, *(output->opencl_image()));

    input_shape_ = input->shape();
  }

  const std::vector<uint32_t> lws = pooling::LocalWS(runtime, gws, kwg_size_);
  std::string tuning_key =
      Concat("pooling_opencl_kernel_", output->dim(0), output->dim(1),
             output->dim(2), output->dim(3));
  MACE_RETURN_IF_ERROR(TuningOrRun3DKernel(runtime, kernel_, tuning_key,
                                           gws, lws, context->future()));

  MACE_OUT_OF_RANGE_VALIDATION;
  return MaceStatus::MACE_SUCCESS;
}

}  // namespace image
}  // namespace opencl
}  // namespace ops
}  // namespace mace

#endif  // MACE_OPS_OPENCL_IMAGE_POOLING_H_
