/**
* This function calculates the difference in years, quarters, months,
* weeks, weekdays, days, hours, minutes and seconds between the object
* and another date passed.
*
* @param $date The other date to be compared. A YDDate object,
* timestamp, array or string. If null, the current date.
*
* @returns An array with all the difference information.
*
* @todo Not very efficient for big differences.
*/
function getDifference($date)
{
if (!extension_loaded('calendar')) {
trigger_error('The PHP calendar extension must be enabled', YD_ERROR);
}
if ($this->isDateEmpty()) {
trigger_error('Cannot make calculations with an empty date', YD_ERROR);
}
$start = $this;
$end = new YDDate($date);
$span = array();
$span['years'] = 0;
$span['quarters'] = 0;
$span['months'] = 0;
$span['weeks'] = 0;
$span['days'] = 0;
$span['weekdays'] = 0;
$span['hours'] = 0;
$span['minutes'] = 0;
$span['seconds'] = 0;
if ($start->timestamp_string == $end->timestamp_string) {
return $span;
}
$julian_start = GregoriantoJD($start->month, $start->day, $start->year);
$julian_end = GregoriantoJD($end->month, $end->day, $end->year);
$days = abs($julian_end - $julian_start);
$years = 0;
$quarters = 0;
$months = 0;
$weeks = 0;
$weekdays = 0;
$hours = 0;
$minutes = 0;
$seconds = 0;
$neg = 1;
$s =& $start;
$e =& $end;
if ($start->timestamp_string > $end->timestamp_string) {
$neg = -1;
$s =& $end;
$e =& $start;
}
$hours += 24 - $s->hours + $e->hours;
if ($s->minutes != $e->minutes) {
$minutes += 60 - $s->minutes + $e->minutes;
}
if ($s->seconds != $s->seconds) {
$seconds += 60 - $s->seconds + $e->seconds;
}
if ($days > 1) {
$hours += $days * 24;
}
$minutes += $hours * 60;
$seconds += $minutes * 60;
$count = $days;
$weekend = $s->isWeekend();
$monthend = $s->isEndOfMonth();
$quarterend = $s->isEndOfQuarter();
$yearend = $s->isEndOfYear();
while ($count > 0) {
if (!$s->isWeekend()) {
if ($weekend) {
$weeks++;
}
$weekdays++;
$weekend = false;
} else {
$weekend = true;
}
if (!$s->isEndOfMonth()) {
if ($monthend) {
$months++;
}
$monthend = false;
} else {
$monthend = true;
}
if (!$s->isEndOfQuarter()) {
if ($quarterend) {
$quarters++;
}
$quarterend = false;
} else {
$quarterend = true;
}
if (!$s->isEndOfYear()) {
if ($yearend) {
$years++;
}
$yearend = false;
} else {
$yearend = true;
}
$s->addDay();
$count--;
}
$span['years'] = $neg * $years;
$span['quarters'] = $neg * $quarters;
$span['months'] = $neg * $months;
$span['weeks'] = $neg * $weeks;
$span['days'] = $neg * $days;
$span['weekdays'] = $neg * $weekdays;
$span['hours'] = $neg * $hours;
$span['minutes'] = $neg * $minutes;
$span['seconds'] = $neg * $seconds;
return $span;
}
/**
* This function adds a number of days to the date.
*
* @param $value (Optional) The number of days. Default: 1.
*
* @returns The date in the 'ISO' format.
*/
function addDay($value = 1)
{
if ($value == 0) {
return $this->get();
}
if (!extension_loaded('calendar')) {
trigger_error('The PHP calendar extension must be enabled', YD_ERROR);
}
if ($this->isDateEmpty()) {
trigger_error('Cannot make calculations with an empty date', YD_ERROR);
}
$julian = GregoriantoJD($this->month, $this->day, $this->year);
$julian += $value;
$gregorian = JDtoGregorian($julian);
list($month, $day, $year) = split('[/]', $gregorian);
$this->day = $day;
$this->month = $month;
$this->year = $year;
$this->reset();
return $this->get();
}
