/**
* @param int $nDays
* @return static
*/
public static function fromInteger($nDays)
{
$fourCentury = 365 * 400 + static::nLeapYears(400);
$century = 365 * 100 + static::nLeapYears(100);
$fourYear = 365 * 4 + 1;
$year = 1 + floor($nDays / $fourCentury) * 400;
$nDays %= $fourCentury;
$year += floor($nDays / $century) * 100;
$nDays %= $century;
$year += floor($nDays / $fourYear) * 4;
$nDays %= $fourYear;
$year += floor($nDays / 365);
$nDays %= 365;
if (static::isLeapYear($year) && $nDays >= 60) {
if ($nDays == 60) {
$month = 2;
$day = 29;
} else {
$month = MiscHelpers::binarySearch($nDays, static::$cumulativeDaysInMonth);
$day = $nDays - static::$cumulativeDaysInMonth[$month - 1] - 2;
}
} else {
$month = MiscHelpers::binarySearch($nDays, static::$cumulativeDaysInMonth);
$day = $nDays - static::$cumulativeDaysInMonth[$month - 1] - 1;
}
return new static($year, $month, $day);
}
public function test_search()
{
$this->assertEquals(0, MiscHelpers::binarySearch(0, [0, 1]));
$this->assertEquals(1, MiscHelpers::binarySearch(1, [0, 2]));
$this->assertEquals(2, MiscHelpers::binarySearch(2, [0, 1]));
$this->assertEquals(0, MiscHelpers::binarySearch(-1, [0, 1]));
$this->assertEquals(1, MiscHelpers::binarySearch(1, [0, 1]));
$this->assertEquals(0, MiscHelpers::binarySearch(0, [0, 1, 2, 3, 4, 5]));
$this->assertEquals(1, MiscHelpers::binarySearch(1, [0, 2, 5, 6, 7]));
$this->assertEquals(5, MiscHelpers::binarySearch(10, [0, 2, 5, 6, 7]));
}
protected function numberOfLeapYearsPast()
{
$y = $this->getYear();
/** @var int $nHops number of 365-day-years followed a five-leap-year*/
$nHops = MiscHelpers::binarySearch($y + 1, static::$fiveLeapYears);
return (int) (($y - $nHops) / 4);
}
