functions.php

<?php

/**
 * convert timeframe array to normal time array
 *
 * @param timestamp $lecture_date
 * @param array $timeframe_time
 * @return array
 */
function build_times_array_from_timeframe($lecture_date, $timeframe_time)
{
  return array(0 => $timeframe_time[0],
               1 => $timeframe_time[1],
               2 => date('j.n.Y', $lecture_date),
               3 => $timeframe_time[2],
               4 => $timeframe_time[3],
               5 => $timeframe_time[4],
               6 => $timeframe_time[5],
               7 => $timeframe_time[6],
               8 => $timeframe_time[7],
               9 => $timeframe_time[8],
               10 => $timeframe_time[9],
               11 => $timeframe_time[10]
              );
}

/**
 * insert time to lectures array
 *
 * @param array $lectures
 * @param timestamp $current_time
 * @param bool $old_items
 * @param array $times
 * @param string $subject
 * @return boolean
 */
function insert_time(&$lectures, $current_time, $old_items, $times, $subject)
{
  if (!strlen($times[6])) $times[6] = '00';
  if (!strlen($times[10])) $times[10] = '00';

  $start  = strtotime($times[2].' '.$times[4].':'.$times[6]);
  $end    = strtotime($times[2].' '.$times[8].':'.$times[10]);

  $year   = (int)date('Y', $start);
  $week   = (int)date('W', $start);
  $day    = (int)date('w', $start);
  $length = $end-$start;

  if (!$start || !$end || !$week || !$year || !$length) return false;

  if (!$old_items && $current_time > $end) return true;

  $lectures[$year][$week][$day][$times[4]][$times[6]][$subject] = array('start_h' => $times[4],
      'start_m' => $times[6],
      'end_h'   => $times[8],
      'end_m'   => $times[10],
      'info'	  => $times[11],
      'start'   => $start,
      'end'     => $end,
      'length'  => $length,
  );

  return true;
}

/**
 * Check if $day array has overlapping items with $item
 *
 * @param array $day
 * @param array $item
 * @return bool
 */
function items_in_day_array_overlap($day, $item)
{
  foreach ($day as $hour)
  {
    if (items_in_hour_array_overlap($hour, $item)) return true;
  }
  return false;
}

/**
 * Check if $hour array has overlapping times with $item
 *
 * @param array $hour
 * @param array $item
 * @return bool
 */
function items_in_hour_array_overlap($hour, $item)
{

  foreach ($hour as $mu_h_minute => $mu_h_subjects)
  {
    foreach ($mu_h_subjects as $mu_h_subject => $mu_h_item)
    {
      if ($mu_h_item == $item) continue;

      if (items_overlap($item, $mu_h_item)) return true;
    }
  }

  return false;
}

/**
 * check if items overlap
 *
 * @param array $item1
 * @param array $item2
 * @return bool
 */
function items_overlap($item1, $item2)
{
  if ($item1['start'] < $item2['start'] && $item2['start'] < $item1['end']) return true;
  if ($item2['start'] < $item1['start'] && $item1['start'] < $item2['end']) return true;

  return false;
}


/**
 * get class for hour slot
 *
 * @param int $reserved_space
 * @param bool $red
 * @param int $next_ending
 * @param bool $subject
 * @param int $extra_slots
 * @return string
 */
function get_class_for_hour_slot($reserved_space, &$red, $next_ending, $subject = false, $extra_slots = false)
{
  static $last_red = false;
  static $last_red2 = false;

  $red = (($red || ($last_red2 && $reserved_space > 0 )) && $reserved_space >= 0);

  $class = ($reserved_space >= 0 || $subject) ? (($reserved_space > 0) ? 'subject_continues' : 'subject') : 'subject empty';

  $class .= $red ? ' red' : '';

  $class .= ($red && $next_ending == 0 && $reserved_space > 0) ? ' dashed' : '';

  $class .= ($last_red && $red && $extra_slots !== false) ? ' dashed_top' : '';

  $last_red2 = $last_red = $red;

  if ($reserved_space <= 0) $last_red2 = false;

  //echo $reserved_space.' '.$next_ending;

  //echo $class;

  return $class;
}

/**
 * Get max hour
 *
 * @param array $week
 */
function get_max_hour($week)
{
  $max = 0;
  for ($day=1; $day<6; $day++)
  {
    if (!isset($week[$day])) continue;

    for($hour=1; $hour<25; $hour++)
    {
      if (!isset($week[$day][$hour])) continue;

      foreach ($week[$day][$hour] as $minute => $subjects)
      {
        if ($max < $hour) $max = $hour;

        foreach ($subjects as $item)
        {
          if ($item['end_h'] > $max && $item['end_m'] != '00') $max = $item['end_h'];
          if ($item['end_h'] > $max && $item['end_m'] == '00') $max = $item['end_h']-1;
        }
      }
    }
  }
  return $max;
}

/**
 * echo page break if needed
 *
 * @param int $week_counter
 * @param int $max_hours
 * @param int $page_hours
 * @param bool $no_break
 */
function echo_page_break(&$week_counter, $max_hours, &$page_hours, &$no_break)
{
  $page_hours += $max_hours;

  if ($page_hours > 48)
  {
    echo '<span  class="page_break "/>';
    $week_counter =  1;
    $page_hours = $max_hours;
  }
  else if ($week_counter++%3 === 0 && !$no_break)
  {
    echo '<span  class="page_break "/>';
    $page_hours = $max_hours;
  }
  else $no_break = false;
}

/**
 * Authenticate user using http digest authentication
 * (http://php.net/manual/en/features.http-auth.php)
 *
 */
function authenticate()
{
  global $valid_users, $l;

  if (empty($_SERVER['PHP_AUTH_DIGEST']))
  {
      header('HTTP/1.1 401 Unauthorized');
      header('WWW-Authenticate: Digest realm="'.$l->auth_realm.
             '",qop="auth",nonce="'.uniqid().'",opaque="'.md5($l->auth_realm).'"');

      die($l->auth_cancel);
  }

  if (!($data = http_digest_parse($_SERVER['PHP_AUTH_DIGEST'])) || !isset($valid_users[$data['username']])) die($l->auth_wrong_credentials);

  // generate the valid response
  $A1 = md5($data['username'] . ':' . $l->auth_realm . ':' . $valid_users[$data['username']]);
  $A2 = md5($_SERVER['REQUEST_METHOD'].':'.$data['uri']);
  $valid_response = md5($A1.':'.$data['nonce'].':'.$data['nc'].':'.$data['cnonce'].':'.$data['qop'].':'.$A2);

  if ($data['response'] != $valid_response) die($l->auth_wrong_credentials);

  // ok, valid username & password
}

/**
 * parse http basic authentication
 * (http://php.net/manual/en/features.http-auth.php)
 *
 * @param string $txt
 * @return array
 */
function http_digest_parse($txt)
{
  // protect against missing data
  $needed_parts = array('nonce'=>1, 'nc'=>1, 'cnonce'=>1, 'qop'=>1, 'username'=>1, 'uri'=>1, 'response'=>1);
  $data = array();
  $keys = implode('|', array_keys($needed_parts));

  preg_match_all('@(' . $keys . ')=(?:([\'"])([^\2]+?)\2|([^\s,]+))@', $txt, $matches, PREG_SET_ORDER);

  foreach ($matches as $m)
  {
    $data[$m[1]] = $m[3] ? $m[3] : $m[4];
    unset($needed_parts[$m[1]]);
  }

  return $needed_parts ? false : $data;
}


/**
 * echo html header
 *
 * @param string $file_prefix
 */
function echo_header($file_prefix = '')
{
  echo <<<END
<html>
<head>
<title>Timetable</title>
<link href="{$file_prefix}style.css" rel="stylesheet" type="text/css">
</head>
<body>
END;
}

/**
 * Echo html footer
 *
 */
function echo_footer()
{
  echo <<<END
</body>
</html>
END;
}