string LCD::GetDate()
{
char buf[20];
string tmp = GetDayOfTheWeek((int) _timed->day, (int) _timed->month, (int) _timed->year);
sprintf(buf, "%02d.%02d.%02d",_timed->day,_timed->month, _timed->year);
tmp.append(buf);
return tmp;
}
/*!
\brief Get the year, month, and day in month from a week in year
\details An ISO week-numbering year has 52 or 53 full weeks (364 or 371 days)
\param year [in, out] Gregorian year
\param weekInYear [in] Gregorian week in a year
\param month [out] Gregorian month
\param dayInMonth [out] Gregorian day in month
\returns \c True if success or \c False if error
*/
bool GetDayAndMonthFromWeekInYear(int *year, int weekInYear, int *month,
int *dayInMonth)
{
int daysInMonth;
int weeksInYear;
*month = ISO_FIRST_MONTH_IN_YEAR;
bool hasChanged;
do
{
hasChanged = false;
weeksInYear = GetNumberOfWeeksInYear(*year);
if (weekInYear > weeksInYear)
{
weekInYear -= weeksInYear;
(*year)++;
hasChanged = true;
}
} while(hasChanged);
int dayInYear = (weekInYear - 1) * ISO_DAYS_A_WEEK + 1;
// Since the first day of week 1 in a year in the Gregorian calendar is not usually January 1st we need to handle the offset
static int t[] = {0, 0, -1, -2, -3, 3, 2, 1};
int jan1DayOfWeek = GetDayOfTheWeek(*year, 1, 1);
dayInYear += t[jan1DayOfWeek];
if (dayInYear <= 0)
{
// dayInYear is in the previous year
(*year)--;
dayInYear += GetDaysInYear(*year);
}
else
{
int daysInYear = GetDaysInYear(*year);
if (dayInYear > daysInYear)
{
// dayInYear is in the next year
(*year)++;
dayInYear -= daysInYear;
}
}
if (!GetDayAndMonthFromDayInYear(*year, dayInYear, month, dayInMonth))
return false;
return true;
}
/*!
\brief Get the number of weeks in a year
\par Algorithm
There are 52 weeks in most years however, years that begin on a Thursday and leap years that begin on a Wednesday have 53 weeks.
*/
int GetNumberOfWeeksInYear(int year)
{
int jan1DayOfWeek = GetDayOfTheWeek(year, 1, 1);
return jan1DayOfWeek == 4 || (jan1DayOfWeek == 3 && IsALeapYear(year)) ? 53 : 52;
}
