/* 	HW1 Onyedi Anyansi
	Calendar */

#include <stdio.h>
#include <math.h>

//2000 starts on saturday
int 	findstartday(int year)
{

	int 	i = 0;
	int 	yc = 2006;
	if (year > 2006)
	{
		while (year > yc)
		{
			if(yc%4 == 0)
			{
				if(yc % 100 == 0)
				{
					if (yc % 400 == 0) i = i + 2;
					else i++;
				}
				else i = i + 2;
			}
			else i++;
			yc++;
		}
		i = i % 7;
	}
	if (year < 2006)
	{
		while (year < yc)
		{
			if((yc-1) % 4 == 0)
			{
				if((yc-1) % 100 == 0)
				{
					if ((yc-1) % 400 == 0) i = i + 2;
					else i++;
				}
				else i = i + 2;
			}
			else i++;
			yc--;
		}
		i = i % 7;
		if (i == 6) i = 1;
		else if (i == 5) i = 2;
		else if (i == 4) i = 3;
		else if (i == 3) i = 4;
		else if (i == 2) i = 5;
		else if (i == 1) i = 6;
	}

return i;
}

int 	printMonthName(int year, int month)
{
	switch(month)
	{
		case 1:
			printf("January %d \n\n",year);
			break;
		case 2:
			printf("February %d \n\n",year);
			break;
		case 3:
			printf("March %d \n\n",year);
			break;
		case 4:
			printf("April %d \n\n",year);
			break;
		case 5:
			printf("May %d \n\n",year);
			break;
		case 6:
			printf("June %d \n\n",year);
			break;
		case 7:
			printf("July %d \n\n",year);
			break;
		case 8:
			printf("August %d \n\n",year);
			break;
		case 9:
			printf("September %d \n\n",year);
			break;
		case 10:
			printf("October %d \n\n",year);
			break;
		case 11:
			printf("November %d \n\n",year);
			break;
		case 12:
			printf("December %d \n\n",year);
			break;

	}
	if (month <= 7)
	{
		if (month % 2 == 1) return 31;
		else if (month == 2)
		{
			if(year % 4 == 0)
			{
				if(year % 100 == 0)
				{
					if (year % 400 == 0) return 29;
					else return 28;
				}
				else return 29;
			}
			else return 28;
		}
		else return 30;
	}
	else
	{
		if (month % 2 == 1) return 30;
		else return 31;
	}
}

int 	printMonth(int year, int month, int day)
{
	int 	days;
	int 	i = 0;
	int 	count = 1;

	days = printMonthName (year, month);
	printf("Sun	Mon	Tue	Wed	Thu	Fri	Sat\n");
	while (i < day)
	{
		//if (day == 0) break;
		printf("	");
		i++;
	}
	while (count <= days)
	{
		if (i >= 6)
		{
			printf("%d	\n", count);
			i = -1;
		}
		else printf("%d	", count);
		i++;
		count++;
	}
	return i;
}

int 	printCalendar(int year, int day)
{
	int	i = 1;
	int 	sday;
	sday = day;

	printf("\n \n!!Calendar for %d!! \n\n",year);
	for (i = 1; i <= 12; i++)
	{
		sday = printMonth(year, i, sday);
		printf("\n \n");
	}
	return 0;
}

int 	main(void)
{
	int 	year, i, lol;
	printf("Enter the year for this calendar:-");
	scanf("%d", &year);
	i = findstartday(year);
	lol = printCalendar(year, i);
	return 0;
}