/*
 Hossien Vismeh  ( IRAN-ARAK )   hepco_kid@yahoo.com  1384/6/26  2005/09/17
 hegri shamsi to miladi and reverse code with C for use in any C compiler
 ( specialy in Microcontrolelr )
  ----- ba tashakor az doost azizam Reza Gamshidi --------
 */

#include <stdio.h>
#include <conio.h>
#include <dos.h>

void miladi_to_shamsi(int y,int *year,char *month,char *day)
{
 const int FST_SIZE = 12;
 int FST[FST_SIZE]  = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };

 int  leap  = 0;
 int  leaps = 0;
 int  tmp;

 (*year) %= 100;

 if(((*year) % 4) == 0) leap = 1;

 for(int idx=2; idx<FST_SIZE; idx++) FST[idx] += leap;

 tmp   = (*year) / 4 + 1;
 leaps = tmp;

 if(((*year)%4) == 0) leaps--;

 tmp = (*year) * 365 + leaps + FST[(*month)-1] + (*day) - 80;

 *year  = y;
 *month = 1;
 *day   = 1;

 for(int i=1;i<=tmp;i++)
 {
  leap = ((*year)+1) % 4;
  (*day)++;

  if( (*day == 32 && *month <= 6) ||
      (*day == 31 && *month >  6) ||
      (*day == 30 && leap != 0 && *month == 12))
				{
					*day = 1;
					(*month)++;
				}

  if(*month == 13)
   {
	*month = 1;
	(*year)++;
   }
  }

  *year += 1300 - (y - 79);

}






void shamsi_to_miladi(int *iyear,char *imonth,char *iday)
{
   if(((*imonth) < 10) || ((*imonth) == 10 && (*iday) < 11))
	    (*iyear) += 621;
   else
	    (*iyear) += 622;

   switch(*imonth)
   {
     case 1:  if ((*iday) < 12)
			  {
		*imonth = 3;
				(*iday) += 20;
			  } else
			  {
				*imonth = 4;
				(*iday) -= 11;
			  } break;

     case 2:  if ((*iday) < 11)
			  {
		*imonth = 4;
				(*iday) += 20;
			  } else
			  {
				*imonth = 5;
				(*iday) -= 10;
			  } break;

     case 3:  if ((*iday) < 11)
			  {
		*imonth = 5;
				(*iday) += 21;
			  } else
			  {
				*imonth = 6;
				(*iday) -= 10;
			  } break;

     case 4:  if ((*iday) < 10)
			  {
		*imonth = 6;
				(*iday) += 21;
			  } else
			  {
				*imonth = 7;
				(*iday) -= 9;
			  } break;

     case 5:
     case 6:
     case 8:  if ((*iday) < 10)
			  {
		(*imonth) += 2;
				(*iday) += 22;
			  } else
			  {
				(*imonth) += 3;
				(*iday) -= 9;
			  } break;

	 case 7:  if ((*iday) < 9)
			  {
		*imonth = 9;
				(*iday) += 22;
			  } else
			  {
				*imonth = 10;
				(*iday) -= 8;
			  } break;

     case 9:  if ((*iday) < 10)
			  {
		*imonth = 11;
				(*iday) += 21;
			  } else
			  {
				*imonth = 12;
				(*iday) -= 9;
			  } break;

     case 10:  if ((*iday) < 11)
			  {
		*imonth = 12;
				(*iday) += 21;
			  } else
			  {
				*imonth = 1;
				(*iday) -= 10;
			  } break;

     case 11:  if ((*iday) < 12)
			  {
		*imonth = 1;
				(*iday) += 20;
			  } else
			  {
				*imonth = 2;
				(*iday) -= 11;
			  } break;

     case 12:  if ((*iday) < 10)
			  {
		*imonth = 2;
				(*iday) += 19;
			  } else
			  {
				*imonth = 3;
				(*iday) -= 9;
			  }
   }

}










void main()
{
int  year_miladi=2005;
char month_miladi=9;
char day_miladi=17;

int year_shamsi=1384;
char month_shamsi=6;
char day_shamsi=28;
printf("\n---------------------------------\n");

printf("Miladi to Shamsi:\n");
printf("Miladi date is: %d/%02d/%02d\r\n",year_miladi,month_miladi,day_miladi);
miladi_to_shamsi(83,&year_miladi,&month_miladi,&day_miladi);
printf("Shamsi date is: %d/%02d/%02d\r\n",year_miladi,month_miladi,day_miladi);

printf("\nShamsi to Miladi:\n");
printf("Miladi date is: %d/%02d/%02d\r\n",year_shamsi,month_shamsi,day_shamsi);
shamsi_to_miladi(&year_shamsi,&month_shamsi,&day_shamsi);
printf("Shamsi date is: %d/%02d/%02d\r\n",year_shamsi,month_shamsi,day_shamsi);

getch();
}