#pragma once

#include "fesa/Core/Types.hpp"

#include <cstddef>
#include <vector>

namespace fesa {

class DenseMatrix {
 public:
  DenseMatrix() = default;
  DenseMatrix(LocalIndex rows, LocalIndex cols) : rows_(rows), cols_(cols), values_(static_cast<std::size_t>(rows * cols), 0.0) {}

  LocalIndex rows() const {
    return rows_;
  }

  LocalIndex cols() const {
    return cols_;
  }

  Real& operator()(LocalIndex row, LocalIndex col) {
    return values_[static_cast<std::size_t>(row * cols_ + col)];
  }

  Real operator()(LocalIndex row, LocalIndex col) const {
    return values_[static_cast<std::size_t>(row * cols_ + col)];
  }

  void add(LocalIndex row, LocalIndex col, Real value) {
    (*this)(row, col) += value;
  }

  std::vector<Real> multiply(const std::vector<Real>& x) const {
    std::vector<Real> y(static_cast<std::size_t>(rows_), 0.0);
    for (LocalIndex i = 0; i < rows_; ++i) {
      Real sum = 0.0;
      for (LocalIndex j = 0; j < cols_; ++j) {
        sum += (*this)(i, j) * x[static_cast<std::size_t>(j)];
      }
      y[static_cast<std::size_t>(i)] = sum;
    }
    return y;
  }

 private:
  LocalIndex rows_ = 0;
  LocalIndex cols_ = 0;
  std::vector<Real> values_;
};

}  // namespace fesa