///////////////////////////////////////////////////////////////
// MT2-Q4 - what does this code do?                          //
//                                                           //
// Jim Fawcett, CSE687 - Object Oriented Design, Spring 2018 //
///////////////////////////////////////////////////////////////

#include <iostream>

template<typename T>
class P {
public:
  P(T t) :t_(t)
  {
    std::cout << "\n  ctor P(T t) invoked";
  }
  T operator()()
  {
    std::cout << "\n  operator()() invoked";
    return t_;
  }
  void operator()(T t)
  {
    std::cout << "\n  operator()(T t) invoked";
    t_ = t;
  }
  ~P()
  {
    std::cout << "\n  dtor ~P() invoked";
  }
private:
  T t_;
};

template<typename W>
class Wrapped
{
public:
  Wrapped(const W& w) : w_(w) 
  {
    std::cout << "\n  Wrapped promoted " << w;
  }
  Wrapped(const Wrapped& wr) : w_(wr.w_)
  {
    std::cout << "\n  " << w_ << " copied";
  }
  Wrapped(Wrapped&& wr) : w_(std::move(wr.w_))
  {
    std::cout << "\n  " << w_ << " moved";
  }
  Wrapped& operator=(const Wrapped& wr)
  {
    if (&wr == this) return *this;
    w_ = wr.w_;
    std::cout << "\n  Wrapped copy assigned";
    return *this;
  }
  Wrapped& operator=(Wrapped&& wr)
  {
    if (&wr == this) return *this;
    w_ = std::move(wr.w_);
    std::cout << "\n  Wrapped move assigned";
  }
  operator W& ()
  {
    std::cout << "\n  Wrapped cast";
    return w_;
  }

  ~Wrapped()
  {
    std::cout << "\n  Wrapped destroyed\n";
  }
private:
  W w_;
};

int main()
{
  std::cout << "\n  MT2-Q4 - what does this code do? (it's a property)";
  std::cout << "\n ----------------------------------------------------\n";

  std::cout << "\n  using P<double>";
  std::cout << "\n -----------------";
  P<double> p(3.14159);
  std::cout << "\n  " << p();
  p(0.3333);
  std::cout << "\n  " << p();
  std::cout << "\n";

  std::cout << "\n  using P<Wrapped<double>> to show details";
  std::cout << "\n ------------------------------------------";
  P<Wrapped<double>> pw(3.14159);
  std::cout << "\n  " << pw();
  pw(0.3333);
  std::cout << "\n  " << pw();
}