/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserve.

   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. */

#include "paddle/operators/conv3dtranspose_op.h"

namespace paddle {
namespace operators {

void Conv3DTransposeOp::InferShape(framework::InferShapeContext* ctx) const {
  PADDLE_ENFORCE(ctx->HasInput("Input"),
                 "Input(Input) of Conv3DTransposeOp should not be null.");
  PADDLE_ENFORCE(ctx->HasInput("Filter"),
                 "Input(Filter) of Conv3DTransposeOp should not be null.");
  PADDLE_ENFORCE(ctx->HasOutput("Output"),
                 "Output(Output) of Conv3DTransposeOp should not be null.");

  auto in_dims = ctx->GetInputDim("Input");
  auto filter_dims = ctx->GetInputDim("Filter");
  std::vector<int> strides = ctx->Attrs().Get<std::vector<int>>("strides");
  std::vector<int> paddings = ctx->Attrs().Get<std::vector<int>>("paddings");

  for (size_t i = 0; i < paddings.size(); ++i) {
    PADDLE_ENFORCE_EQ(paddings[i], 0,
                      "No Padding allowed in conv transpose op.");
  }

  PADDLE_ENFORCE_EQ(in_dims.size(), 5,
                    "Conv3DTransposeOp input should be 5-D tensor.");
  PADDLE_ENFORCE_EQ(filter_dims.size(), 5,
                    "Conv3DTransposeOp filter should be 5-D tensor.");
  PADDLE_ENFORCE_EQ(in_dims[1], filter_dims[0],
                    "input and kernel input dimension should be equal.");

  std::vector<int64_t> output_shape({in_dims[0], filter_dims[1]});
  for (size_t i = 0; i < paddings.size(); ++i) {
    output_shape.push_back((in_dims[i + 2] - 1) * strides[i] +
                           filter_dims[i + 2]);
  }
  ctx->SetOutputDim("Output", framework::make_ddim(output_shape));
}

Conv3DTransposeOpMaker::Conv3DTransposeOpMaker(
    framework::OpProto* proto, framework::OpAttrChecker* op_checker)
    : OpProtoAndCheckerMaker(proto, op_checker) {
  AddInput(
      "Input",
      "(Tensor) The input tensor of convolution transpose operator."
      "The format of input tensor is NCDHW. Where N is batch size, C is "
      "the number of channels, D, H and W is the depth, height and width of "
      "feature.");
  AddInput("Filter",
           "(Tensor) The filter tensor of convolution transpose operator."
           "The format of the filter tensor is CMDHW, where C is the number of "
           "output image channels, M is the number of input image channels, "
           "D, H and W is depth, height and width of filter. "
           "We enforce groups number == 1 and padding == 0 in "
           "convolution transpose Scenario.");
  AddOutput("Output",
            "(Tensor) The output tensor of convolution transpose operator."
            "The format of output tensor is also NCDHW."
            "Where N is batch size, C is "
            "the number of channels, D, H and W is the depth, height and "
            "width of feature.");
  AddAttr<std::vector<int>>("strides",
                            "strides of convolution transpose operator.")
      .SetDefault({1, 1, 1});
  AddAttr<std::vector<int>>("paddings",
                            "paddings of convolution transpose operator.")
      .SetDefault({0, 0, 0});
  AddComment(R"DOC(
The convolution transpose operation calculates the output based on the input, filter
and strides, paddings, groups parameters. The size of each dimension of the
parameters is checked in the infer-shape.
)DOC");
}

void Conv3DTransposeOpGrad::InferShape(
    framework::InferShapeContext* ctx) const {
  auto in_dims = ctx->GetInputDim("Input");
  auto filter_dims = ctx->GetInputDim("Filter");
  if (ctx->HasOutput(framework::GradVarName("Input"))) {
    ctx->SetOutputDim(framework::GradVarName("Input"), in_dims);
  }
  if (ctx->HasOutput(framework::GradVarName("Filter"))) {
    ctx->SetOutputDim(framework::GradVarName("Filter"), filter_dims);
  }
}

}  // namespace operators
}  // namespace paddle

namespace ops = paddle::operators;
REGISTER_OP(conv3dtranspose, ops::Conv3DTransposeOp,
            ops::Conv3DTransposeOpMaker, conv3dtranspose_grad,
            ops::Conv3DTransposeOpGrad);

REGISTER_OP_CPU_KERNEL(
    conv3dtranspose,
    ops::GemmConv3DTransposeKernel<paddle::platform::CPUPlace, float>);
REGISTER_OP_CPU_KERNEL(
    conv3dtranspose_grad,
    ops::GemmConv3DTransposeGradKernel<paddle::platform::CPUPlace, float>);