/* Copyright 2019 The fast_sparse_interpolation Authors. 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.
==============================================================================*/

#pragma once

#include <Interpolation.hpp>
#include <Iterators.hpp>
#include <chrono>
#include <cmath>
#include <iostream>
#include <vector>

inline double f(std::vector<double> point) {
  double prod = 1.0;
  for (size_t dim = 0; dim < point.size(); ++dim) {
    prod *= point[dim];
  }
  return prod;
}

class GoldenPointDistribution {
  static constexpr double golden_ratio = 0.5 * (1.0 + sqrt(5));

 public:
  double operator()(size_t idx) {
    double value = (idx + 1) * golden_ratio;
    return value - int(value);
  }
};

class SimplePointDistribution {
 public:
  double operator()(size_t idx) {
    if (idx == 0) {
      return 0.0;
    } else if (idx == 1) {
      return 1.0;
    } else {
      return 0.5;
    }
  }
};

class MonomialFunctions {
 public:
  std::function<double(double)> operator()(size_t idx) {
    return [=](double x) { return pow(x, idx); };
  }
};

template <class T>
inline std::ostream &operator<<(std::ostream &os, const std::vector<T> &v) {
  os << "[";
  for (auto ii = v.begin(); ii != v.end(); ++ii) {
    os << " " << *ii;
  }
  os << " ]";
  return os;
}

template <typename It>
std::ostream &operator<<(std::ostream &os, fsi::MultiDimVector<It> const &v) {
  for (size_t i = 0; i < v.data.size(); ++i) {
    std::cout << v.data[i] << "\n\n";
  }

  return os;
}

inline double measure_execution_time(std::function<void()> f) {
  auto start = std::chrono::high_resolution_clock::now();
  f();
  auto finish = std::chrono::high_resolution_clock::now();
  std::chrono::duration<double> elapsed = finish - start;
  return elapsed.count();
}

class Timer {
  std::chrono::system_clock::time_point start;

 public:
  Timer() : start(std::chrono::high_resolution_clock::now()){};
  void reset() { start = std::chrono::high_resolution_clock::now(); }
  double elapsed() {
    auto finish = std::chrono::high_resolution_clock::now();
    std::chrono::duration<double> elapsed = finish - start;
    return elapsed.count();
  }
};

void measurePerformance();