//  Calendar Information (copyright 1992, Information Disciplines, Inc.)
//  --------------------

//  This pseudo-class defines public constants and utility functions
//  used in manipulating dates.  It is independent of any date representation
//  or Date class.  (It is used by IDI's Date class -- see Date.hpp.)

#ifndef CALENDAR
#define CALENDAR

#include "global.hpp"
#include "SimpleString.hpp"

namespace Calendar {

//  Constants
//  ---------

  static SHORT   days_per_year      =  365;
  static LONG    days_per_4_years   =  1 +  4 * days_per_year;
  static LONG    days_per_100_years = -1 + 25 * days_per_4_years;
  static LONG    days_per_400_years =  1 +  4 * days_per_100_years;

  static SHORT   days_in_month     [13] = {0, 31, 28, 31, 30, 31, 30,
                                              31, 31, 30, 31, 30, 31};
  static SHORT   days_before_month [13] = {0,  0, 31, 59, 90,120,151,
                                             181,212,243,273,304,334};
  
  static const char *const  month_name        [13]
    = {"","January", "February", "March"    , "April"  , "May"     , "June" ,
       "July"   , "August"  , "September", "October", "November", "December"};
  
  static const char *const  day_name          [ 7] = 
     {"Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"};


//  Utility function declarations (defined in Calendar.cpp)
//  -----------------------------
   
   bool isLeapYear(INT yyyy);

   bool isLegalYMD(INT yyyy, SHORT mm, SHORT dd); // Validate year-month-day

   short dayNumber(INT yyyy, INT mm, INT dd);

   void ymd       (INT yyyy_in, short& mm_out, short& ddd_in_out);

   SimpleString toEnglish(INT yyyy, SHORT mm, SHORT dd);
 
   SimpleString toString(INT yyyy, SHORT mm, SHORT dd);

 };

#endif