+ // Handle a normalized duration value.
+ if (preg_match('/^\d{1,3}:[0-5][0-9]$/', $duration )) { // 0:00 - 999:59
+ $time_array = explode(':', $duration);
+ $minutes = (int)@$time_array[1] + ((int)@$time_array[0]) * 60;
+ return $minutes > $max ? false : $minutes;
+ }
+
+ // Handle localized fractional hours.
+ global $user;
+ $localizedPattern = '/^(\d{1,3})?['.$user->decimal_mark.'][0-9]{1,4}h?$/';
+ if (preg_match($localizedPattern, $duration )) { // decimal values like .5, 1.25h, ... .. 999.9999h (or with comma)
+ if ($user->decimal_mark == ',')
+ $duration = str_replace (',', '.', $duration);
+
+ $minutes = (int)round(60 * floatval($duration));
+ return $minutes > $max ? false : $minutes;
+ }
+
+ // Handle minutes. Some users enter durations like 10m (meaning 10 minutes).
+ if (preg_match('/^\d{1,5}m$/', $duration )) { // 0m - 99999m
+ $minutes = (int) trim($duration, 'm');
+ return $minutes > $max ? false : $minutes;
+ }
+
+ // Everything else is not a valid duration.
+ return false;
+ }
+
+ // minutesToDuration converts an integer number of minutes into duration string.
+ // Formats returned HH:MM, HHH:MM, HH, or HHH.
+ static function minutesToDuration($minutes, $abbreviate = false) {
+ if ($minutes < 0) return false;
+
+ $hours = (string) (int)($minutes / 60);
+ $mins = (string) round(fmod($minutes, 60));
+ if (strlen($mins) == 1)
+ $mins = '0' . $mins;
+ if ($abbreviate && $mins == '00')
+ return $hours;
+
+ return $hours.':'.$mins;