//time.cpp
//an example of a simple time class

//header file(s)
#include <iostream>  //for cin, cout, and endl
using namespace std;

//class declaration

class Time {
  public:
    //use default constructors and 
    //destructors
    bool Set12(int hr, int min, char ap);
    //returns false if an invalid time 
    //is entered
    //noon is 12:00 am, 
    //midnight is 12:00 pm.

    bool Set24(int hr, int min);
    //returns false if an invalid time 
    //is entered
    //noon is 12:00, midnight is 00:00.

    int GetMinutes();
    int GetHour12();
    int GetHour24();
    char GetAMPM();
    void Display12();
    void Display24();
  private:
    int hour;  //stored on 24 hour clock
    int minute;
  }; //end of time class

//implementation of class functions

bool Time::Set12(int hr, int min, char ap)
//Sets time when given hours and minutes
//in 12 hour format.
//When an invalid time 
//is entered, sets time to noon and 
//returns false.
//noon is 12:00 am, midnight is 12:00 pm.
  {
  //set to a valid time, noon
  hour=12;
  minute=0;
  if ((hr<1) || (min<0) || (min>59) 
             || (hr>12))
        // || is OR
    return 0;  //0 is false

  if ((ap!='a') && (ap!='A') && (ap!='p')
                && (ap!='P'))
        // && is AND
        // symbols in single quotes 
        // are characters
    return 0;
    
  //Got here only if valid time
  if ((ap=='a') || (ap=='A')) // am
        // == is comparison EQUAL
    hour=hr;
        // = is ASSIGNMENT
  else  // pm
    hour=hr+12;
  minute=min;
  if (hour == 24)
    hour = 0;

  return 1; //any nonzero integer is true
  } //end set12

bool Time::Set24(int hr, int min)
//Sets time when given hours and minutes
//in 24 hour format.
//When an invalid time 
//is entered, sets time to noon and 
//returns false.
//noon is 12:00, midnight is 0:00.

  //set default time

  {
  hour = 12;
  minute = 0;
  if ((hr<0) || (min<0) || (min>59) 
             || (hr>=24))
        // || is OR
    return 0;  //0 is false

  hour=hr;
  minute=min;
  return 1; //any nonzero integer is true
  } //end set24
  

int Time::GetMinutes()
  {return minute;}

int Time::GetHour12()
  {
  if ((hour<=12) && (hour>=1))
    return hour;
  else if (hour==0)
    return 12;
  else
    return hour-12;
  }

int Time::GetHour24()
  {return hour;}

char Time::GetAMPM()
  {
  if (hour>0 && hour<=11)
    return 'A';
  else if ((hour==12) && (minute==0))
    return 'A';
  else if ((hour==0) && (minute>0))
    return 'A';
  else 
    return 'P';
  }  //end GetAMPM

void Time::Display12()
  {
  cout << GetHour12() << ':'
    << minute << ' '
    << GetAMPM() << 'M';
  return;
  }  //end Display12

void Time::Display24()
  {
  cout << hour << ':' << minute;
  }

//end of Time implementation

int main()
  {
  Time dawn;
  cout << "Before anything"
    << " has been set: ";
  dawn.Display24();
  dawn.Set12(5,30,'a');
  cout << "\nOnce set properly: ";
  dawn.Display12();
  cout << "\nor on a 24 hour clock: ";
  dawn.Display24();

  Time dusk;
  dusk.Set24(20,14);
  cout << "\n\nDusk in Denmark:  ";
  dusk.Display24();
  cout << "\nDusk in Syracuse:  ";
  dusk.Display12();
  
  Time bad;
  bad.Set12(5, 70, 'a');
  cout << "\n\nBad time:  ";
  bad.Display12();
  cout << endl;
  if (bad.Set24(36,00))
    {
    //Only gets here if request
    //to set was a good one.
    cout << "Good time: ";
    bad.Display24();
    cout << '\n';
    }
  else
    cout << "Invalid time.\n";

  //You can't use private information
  //outside the member functions.
  //Try
  //minute=75;
  //dusk.minute=-32;

  return 0;
  } //end main