/**
* Validate the input value and set the value of @see validPattern if the input machtes a pattern
*
* @param string $value The format string to validate
* @param null $context The form context (ignored)
*
* @return bool True when the input is valid, otherwise false
*
* @see Zend_Validate_Abstract::isValid()
*/
public function isValid($value, $context = null)
{
$this->validPattern = false;
if (!is_string($value) && !is_int($value)) {
$this->error('INVALID_TYPE');
return false;
}
if ($this->isUnixTimestamp($value)) {
$dt = DateTimeFactory::create();
$dt->setTimestamp($value);
} else {
if (!isset($this->patterns)) {
throw new ProgrammingError('There are no allowed timeformats configured');
}
$match_found = false;
foreach ($this->patterns as $pattern) {
$dt = DateTimeFactory::parse($value, $pattern);
if ($dt !== false && $dt->format($pattern) === $value) {
$match_found = true;
$this->validPattern = $pattern;
break;
}
}
if (!$match_found) {
$this->_error('NO_MATCHING_PATTERN');
return false;
}
}
return true;
}
/**
* Calculate the labels for this dataset
*
* @param integer $unit The unit to use as the basis for calculation
*/
private function calculateLabels($unit)
{
$fac = DateTimeFactory::create();
$duration = $this->getMax() - $this->getMin();
// Calculate number of ticks, but not more than 30
$tickCount = $duration / $unit * 10;
if ($tickCount > 30) {
$tickCount = 30;
}
$step = $duration / $tickCount;
$format = $this->timeFormat;
if ($unit === self::DAY) {
$format = $this->dateFormat;
} elseif ($unit === self::MONTH) {
$format = $this->dateFormat;
}
for ($i = 0; $i <= $duration; $i += $step) {
$this->labels[] = $fac->setTimestamp($this->getMin() + $i)->format($format);
}
}
/**
* @param $weekday
*
* @return string
*/
private function weekdayName($weekday)
{
$sun = DateTimeFactory::create('last Sunday');
$interval = new DateInterval('P' . $weekday . 'D');
$sun->add($interval);
return $sun->format('D');
}
