typedef struct datetime
{
	struct date {
		int year;
		int month; // 0-11
		int day;   // 0-6
	} date;

	struct time {
		int hours;   // 0-23
		int minutes; // 0-59
		int seconds; // 0-60 (not 59 because leap seconds)
	} time;
} datetime;

void datetime_init(datetime* dt);

// Times are expected to be UTC
void datetime_set_date(datetime* dt, int year, int month, int day);
void datetime_set_time(datetime* dt, int hours, int minutes, int seconds);

void datetime_diff(datetime* dt_from, datetime* dt_to, datetime* dt_res);

void datetime_print(datetime* dt);