/* Copyright (c) 2016 Baidu, Inc. 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 <cmath>
#include <gtest/gtest.h>
#include "paddle/math/Matrix.h"

using namespace paddle;  // NOLINT
using namespace std;     // NOLINT

namespace autotest {

class AssertEqual {
public:
  AssertEqual(real err = 0) : err_(err) {}

  inline bool operator()(real a, real b) {
    if (err_ == 0) {
      if (a != b) {
        return false;
      }
    } else {
      if (std::fabs(a - b) > err_) {
        if ((std::fabs(a - b) / std::fabs(a)) > (err_ / 10.0f)) {
          return false;
        }
      }
    }
    return true;
  }

private:
  real err_;
};

template <typename Tensor>
class CopyToCpu;

template <>
class CopyToCpu<CpuMatrix> {
public:
  explicit CopyToCpu(const CpuMatrix& arg) : arg_(arg) {}
  const CpuMatrix& copiedArg() const { return arg_; }

private:
  const CpuMatrix& arg_;
};

template <>
class CopyToCpu<GpuMatrix> {
public:
  explicit CopyToCpu(const GpuMatrix& arg)
    : arg_(arg.getHeight(), arg.getWidth()) {
    arg_.copyFrom(arg);
  }
  CpuMatrix& copiedArg() { return arg_; }

private:
  CpuMatrix arg_;
};

template<typename AssertEq>
void TensorCheck(AssertEq compare,
                 const CpuMatrix& matrix1,
                 const CpuMatrix& matrix2) {
  CHECK(matrix1.getHeight() == matrix2.getHeight());
  CHECK(matrix1.getWidth() == matrix2.getWidth());

  int height = matrix1.getHeight();
  int width = matrix1.getWidth();
  const real* data1 = matrix1.getData();
  const real* data2 = matrix2.getData();
  int count = 0;
  for (int i = 0; i < height; i++) {
    for (int j = 0; j < width; j++) {
      real a = data1[i * width + j];
      real b = data2[i * width + j];
      if (!compare(a, b)) {
        count++;
      }
    }
  }
  EXPECT_EQ(count, 0) << "There are " << count << " different element.";
}

template<typename AssertEq, typename Tensor1, typename Tensor2>
extern void TensorCheck(AssertEq compare,
                        const Tensor1& tensor1,
                        const Tensor2& tensor2) {
  TensorCheck(
    compare,
    CopyToCpu<Tensor1>(tensor1).copiedArg(),
    CopyToCpu<Tensor2>(tensor2).copiedArg());
}

}  // namespace autotest