/**
* Returns date of the first day of the month in the number of months
* from the given date
*
* @param int $months the number of months from the date provided.
* Positive numbers go into the future.
* Negative numbers go into the past.
* 0 is the month presented in $month.
* @param string $month the month, default is current local month
* @param string $year the year in four digit format, default is the
* current local year
* @param string $format the string indicating how to format the output
*
* @return string the date in the desired format
* @access public
* @static
* @since Method available since Release 1.4.4
*/
function beginOfMonthBySpan($months = 0, $month = 0, $year = null, $format = DATE_CALC_FORMAT)
{
if (is_null($year)) {
$year = Date_Calc::dateNow('%Y');
}
if (empty($month)) {
$month = Date_Calc::dateNow('%m');
}
return Date_Calc::addMonths($months, Date_Calc::getFirstDayOfMonth($month, $year), $month, $year, $format);
}
/**
* Returns day on which Summer time starts or ends for given year
*
* The limit (start or end) code can take the following forms:
* 5 the fifth of the month
* lastSun the last Sunday in the month
* lastMon the last Monday in the month
* Sun>=8 first Sunday on or after the 8th
* Sun<=25 last Sunday on or before the 25th
*
* @param string $ps_summertimelimitcode code which specifies Summer time
* limit day
* @param int $pn_month start or end month
* @param int $pn_year year for which to calculate Summer
* time limit day
*
* @return int
* @access private
* @since Method available since Release 1.5.0
*/
function getSummerTimeLimitDay($ps_summertimelimitcode, $pn_month, $pn_year)
{
if (preg_match('/^[0-9]+$/', $ps_summertimelimitcode)) {
$hn_day = $ps_summertimelimitcode;
} else {
if (!isset($ha_daysofweek)) {
static $ha_daysofweek = array("Sun" => 0, "Mon" => 1, "Tue" => 2, "Wed" => 3, "Thu" => 4, "Fri" => 5, "Sat" => 6);
}
if (preg_match('/^last(Sun|Mon|Tue|Wed|Thu|Fri|Sat)$/', $ps_summertimelimitcode, $ha_matches)) {
list($hn_nmyear, $hn_nextmonth, $hn_nmday) = explode(" ", Date_Calc::beginOfMonthBySpan(1, $pn_month, $pn_year, "%Y %m %d"));
list($hn_year, $hn_month, $hn_day) = explode(" ", Date_Calc::prevDayOfWeek($ha_daysofweek[$ha_matches[1]], $hn_nmday, $hn_nextmonth, $hn_nmyear, "%Y %m %d", false));
// not including
// this day
if ($hn_month != $pn_month) {
// This code happen legitimately if the calendar jumped some days
// e.g. in a calendar switch, or the limit day is badly defined:
//
$hn_day = Date_Calc::getFirstDayOfMonth($pn_month, $pn_year);
}
} else {
if (preg_match('/^(Sun|Mon|Tue|Wed|Thu|Fri|Sat)([><]=)([0-9]+)$/', $ps_summertimelimitcode, $ha_matches)) {
if ($ha_matches[2] == "<=") {
list($hn_year, $hn_month, $hn_day) = explode(" ", Date_Calc::prevDayOfWeek($ha_daysofweek[$ha_matches[1]], $ha_matches[3], $pn_month, $pn_year, "%Y %m %d", true));
// including
// this day
if ($hn_month != $pn_month) {
$hn_day = Date_Calc::getFirstDayOfMonth($pn_month, $pn_year);
}
} else {
list($hn_year, $hn_month, $hn_day) = explode(" ", Date_Calc::nextDayOfWeek($ha_daysofweek[$ha_matches[1]], $ha_matches[3], $pn_month, $pn_year, "%Y %m %d", true));
// including
// this day
if ($hn_month != $pn_month) {
$hn_day = Date_Calc::daysInMonth($pn_month, $pn_year);
}
}
}
}
}
return $hn_day;
}