// Time class
// Version 1.4
//
// New in this version: operators.

#include <fstream>
using std::ifstream;

#include <iostream>
using std::cout;
using std::cin;
using std::istream;
using std::ostream;

class Time
{
public:
    friend istream & operator>>(istream & in, Time & t);

    Time() : Time(99, 99) {}
    Time(int h) : Time(h, 0) {}
    Time(int h, int m) : hours_(h), minutes_(m) {}

//    double operator-(const Time & t2) const;

    int hours() const { return hours_; }
    int minutes() const { return minutes_; }

    void set_hours(int new_hours) { hours_ = new_hours; }
    void set_minutes(int new_minutes) { minutes_ = new_minutes; }

    void set(int new_hours, int new_minutes = 0);

private:
    int hours_;
    int minutes_;
};

inline void Time::set(int new_hours, int new_minutes)
{
    hours_ = new_hours;
    minutes_ = new_minutes;
}

//inline double Time::operator-(const Time & t2) const
//{
//    return (hours_ + minutes_/60.0) -
//        (t2.hours_ + t2.minutes_/60.0);
//}

inline double operator-( const Time & t1, const Time & t2 )
{
    return (t1.hours() + t1.minutes()/60.0) -
        (t2.hours() + t2.minutes()/60.0);
}

inline istream & operator>>(istream & in, Time & t)
{
//    int new_hours;
//    in >> new_hours;
//    t.set_hours(new_hours);
    in >> t.hours_;
    in.get(); // colon
    in >> t.minutes_;
    return in;
}

inline ostream & operator<<(ostream & out, const Time & t)
{
    out << t.hours() << ':';
    if ( t.minutes() < 10 ) out << '0';
    out << t.minutes();
    return out;
}

int main()
{
    cout << "Testing subtraction operator...\n";
    Time t1(8,30), t2(6,15);
    cout << t1 - t2 << '\n';

    cout << t2 - 6 << '\n';
    cout << 7 - t2 << '\n';

    cout << "\nTesting input and output operators...\n";
    ifstream f("times.txt");
    Time t;
    while (f >> t) cout << t << '\n';

    cout << "\nTesting chains of input and output operators...\n"
         << "Enter two times: ";
    cin >> t1 >> t2;
    cout << t1 << ' ' << t2 << '\n';

    return 0;
}