<?php

function umlaute($string) {
   $string = str_replace("ä", "&auml;", $string);
   $string = str_replace("ü", "&uuml;", $string);
   $string = str_replace("ö", "&ouml;", $string);
   $string = str_replace("Ä", "&Auml;", $string);
   $string = str_replace("Ü", "&Uuml;", $string);
   $string = str_replace("Ö", "&Ouml;", $string);
   
   return $string;
}

function escape($connection, $string) {
  return str_replace('\n','', trim(mysqli_real_escape_string($connection, $string)));
}

function timeLessThan($hour1, $minute1, $hour2, $minute2) {
	$val1 = $hour1 * 60 + $minute1;
	$val2 = $hour2 * 60 + $minute2;

	if( $val1 < $val2 ){
		return true;
	} else {
		return false;
	}
}

function timeI2S( $hour, $minute, $separator ) {
	return str_pad($hour, 2, '0') . $separator . str_pad($minute, 2, '0');
}

function stepCount($hour1, $minute1, $hour2, $minute2, $intervall) {
	$val1 = $hour1 * 60 + $minute1;
	$val2 = $hour2 * 60 + $minute2;

	$retval = (($val2 - $val1) / $intervall);
	return $retval;
}

function login( $token ) {
	$expectedToken = sha1( MAGIC_WORD . date(MAGIC_DATE) );
	return ($expectedToken === $token);
}

function registrationDate() {
    $today = new DateTime();
    $currentYear = $today->format('Y');
    $currentMonth = $today->format('m');
    $currentDate = $today->format('d');

    if ($currentDate === 1) {
        return new DateTime("$currentYear-$currentMonth-01"); // Today is the 1st of the month.
    } elseif ($currentDate <= 20) {
        return new DateTime("$currentYear-$currentMonth-15"); // Return the 15th of the current month.
    } else {
      $nextMonth = $today->modify('first day of next month'); // Advance to the first day of the next month.
      return $nextMonth;
    }
}

?>