date.h

#ifndef __SHAREWIZ_DATE_H__
#define __SHAREWIZ_DATE_H__
 
// Jan 1 4713 BC is used by astronomers as their starting point.
// Monday Jan 1, 1 AD.  //   1721425 days diff from Jan 1 4713 BC.
// 1992 and 2000 were leapyears.  1800 was not.
 
const int Sun = 0;
const int Mon = Sun + 1;
const int Tue = Mon + 1;
const int Wed = Tue + 1;
const int Thu = Wed + 1;
const int Fri = Thu + 1;
const int Sat = Fri + 1;
 
 
class Date
{
protected:
  long date;
 
public:
  Date();
 
  friend long operator- (const Date& a, const Date& b);
  friend Date operator+ (const Date& a, const long& b);
 
  long getDate();
 
  void setDate(long _date);
  void setWeekdayOnOrBefore(int _weekday);
};
 
 
class DateGregorian : public Date
{
protected:
  int year;
  int month;
  int day;
 
  bool isLeapYear(int _year)
  {
    if ((_year % 400) == 0) return true;
    if ((_year % 100) == 0) return false;
    if ((_year % 4) == 0) return true;
    return false;
  }
 
  int daysInMonth(int _year, int _month)
  {
    int m[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
    if (_month == 2 && isLeapYear(_year))
      return 29;
    return m[_month - 1];
  }
 
public:
  DateGregorian();
  DateGregorian(int _year, int _month, int _day);
  DateGregorian(Date _date);
 
  int getDayOfWeek();
 
  void setDate(int _year, int _month, int _day);
  void setDate(long _date);
  void print();
  void easter(int _year);
};
 
 
class DateJulian : public DateGregorian
{
  /*
protected:
  int year;
  int month;
  int day;
  */
  bool isLeapYear(int _year)
  {
    if ((_year % 4) == 0) return true;
    return false;
  }
 
public:
  DateJulian();
  DateJulian(int _year, int _month, int _day);
  DateJulian(Date d);
 
  void setDate(int _year, int _month, int _day);
  void setDate(long d);
 
  //void print();
  void easter(int _year);
};
 
 
 
#endif