// Ex8_04.cpp
// Implementing the comparison operators
#include <iostream>                    // For stream I/O
#include <utility>                     // For operator overload templates
using std::cout;
using std::endl;
using namespace std::rel_ops;

class CBox                             // Class definition at global scope
{
public:
  // Constructor definition
  explicit CBox(double lv = 1.0, double wv = 1.0, double hv = 1.0) :
    m_Length{ lv }, m_Width{ wv }, m_Height{ hv }
  {
    cout << "Constructor called." << endl;
  }

  // Function to calculate the volume of a box
  double volume() const
  {
    return m_Length*m_Width*m_Height;
  }

  // Operator function for 'less than' that
  // compares volumes of CBox objects.
  bool operator<(const CBox& aBox) const
  {
    return this->volume() < aBox.volume();
  }
  // 'Less than' operator function to compare a CBox object volume with a constant
  bool operator<(const double value) const
  {
    return this->volume() < value;
  }
  // 'Greater than' function to compare a CBox object volume with a constant
  bool operator>(const double value) const
  {
    return this->volume() > value;
  }

  // Overloaded equality operator
  bool operator==(const CBox& aBox) const
  {
    return this->volume() == aBox.volume();
  }

  // Destructor definition
  ~CBox()
  {
    cout << "Destructor called." << endl;
  }

private:
  double m_Length;                   // Length of a box in inches
  double m_Width;                    // Width of a box in inches
  double m_Height;                   // Height of a box in inches
};

// Function comparing a constant with a CBox object
inline bool operator<(const double value, const CBox& aBox)
{
  return value < aBox.volume();
}

int main()
{
  CBox smallBox{ 4.0, 2.0, 1.0 };
  CBox mediumBox{ 10.0, 4.0, 2.0 };
  CBox otherBox{ 2.0, 1.0, 4.0 };
  if (mediumBox != smallBox)
    cout << "mediumBox is not equal to smallBox" << endl;

  if (mediumBox > smallBox)
    cout << "mediumBox is bigger than smallBox" << endl;
  else
    cout << "mediumBox is not bigger than smallBox" << endl;

  if (otherBox >= smallBox)
    cout << "otherBox is greater than or equal to smallBox" << endl;
  else
    cout << "otherBox is smaller than smallBox" << endl;

  if (otherBox >= mediumBox)
    cout << "otherBox is greater than or equal to mediumBox" << endl;
  else
    cout << "otherBox is smaller than mediumBox" << endl;

  if (mediumBox > 50.0)
    cout << "mediumBox capacity is more than 50" << endl;
  else
    cout << "mediumBox capacity is not more than 50" << endl;

  if (10.0 < smallBox)
    cout << "smallBox capacity is more than 10" << endl;
  else
    cout << "smallBox capacity is not more than 10" << endl;

  return 0;
}