// 22.5HV2 Software Engineering II
// Unit 3 Exercise 1

#include <iostream.h>
#include <iomanip.h>
#include "clock.h"

Clock::Clock(int h, int m, int s): hour(h), minute(m), second(s) {normalise();}

Clock& Clock::operator++(int) {
  second++;
  normalise();
  return *this;  // allows increment expression to be used on rhs of assignment
}

void Clock::normalise() {
    minute = minute + second / 60; // change minute if second > 60
    hour = hour + minute/60;       // change hour if minute > 60
    minute = minute%60;            // modulo 60 minutes             
    hour = hour%24;                // modulo 24 hours
    second = second%60;            // modulo 60 seconds
    if (second < 0)
      {
	second+=60;
	minute--;
      }
    if (minute < 0)
      {
	minute+=60;
	hour--;
      }
    if (hour < 0)
      {
	hour += 24;
      }
}

Clock& Clock::operator--(int) {
  
  second--;
  normalise();
  return *this;
}   

ostream& operator<<(ostream& ostr, const Clock& c) {
   return ostr << setfill('0') << setw(2) << c.hour << ":" 
               << setw(2) << c.minute << ":" << setw(2) << c.second;
}