*   Adds a new class to the schedule.

   *

   * \param $slot

   *   Currently, the Schedule class is not smart enough to understand

   *   CourseSlots. At a lower level, we split Courses with multiple

   *   CourseSlots into multiple Course objects with redundant

   *   information.

   */

  function addCourse($course_id, $title)

  {

    $this->courses[] = new Course($course_id, $title);

  }

  /**

   * \brief

   *   Adds a section to this semester after finding the class.

   *

   * \param $instructor

   *   The instructor of this section/section_meeting.

   *

   * \return

   *   NULL on success, a string on error which is a message for the

   *   user and a valid XHTML fragment.

   */

  {

    if (empty($letter) && (empty($time_start) || !strcmp($time_start, 'none')) && (empty($time_end) || !strcmp($time_end, 'none')) && empty($days)

	&& empty($synonym) && empty($instructor) && empty($location) && (empty($type) || !strcmp($type, 'lecture'))

	&& (empty($slot) || !strcmp($slot, 'default')))

      return;

    /* reject invalid times */

    if (!strcmp($time_start, 'none') || !strcmp($time_end, 'none')

	|| $time_start > $time_end)

      {

	return 'Invalid time specifications for ' . htmlentities($course_name) . '-' . htmlentities($letter)

	  . '. Start time: <tt>' . htmlentities($time_start) . '</tt>. End time: <tt>' . htmlentities($time_end) . '</tt>.';

      }

    if (!empty($credit_hours) && !is_numeric($credit_hours))

      {

        return 'Invalid credit-hour specification of <tt>' . htmlentities($credit_hours) . '</tt> for ' . htmlentities($course_name) . '-' . htmlentities($letter) . '. Please use a floating point number or do not enter anything if the number of credit hours is not known.';

      }

    foreach ($this->courses as $course)

      if (!strcmp($course_name, $course->getName()))

	{

	  $section = $course->section_get($letter);

	  if (!$section)

	    {

              $section = new Section($letter, array(), $synonym, $credit_hours);

	      $course->section_add($section, $slot);

	    }

	  return;

	}

    error_log('Could not find class when parsing schedule from postData: ' . $course_name);

    echo 'Could not find class: ' . $course_name . "<br />\n";

  }

  /**

   * \brief

   *   Get the school associated with this schedule.

   *

   * \return

   *   The school associated with this schedule or some fallback.

   */

  public function school_get()

  {

    $school = NULL;

    if (!empty($this->school_id))

      /*

       * May return NULL, so we don't just return this value right

       * away -- we fall through.

       */

/*

 * Copyright 2010 Nathan Gelderloos, Ethan Zonca, Nathan Phillip Brink

 *

 * This file is part of SlatePermutate.

 *

 * SlatePermutate is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Affero General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * SlatePermutate is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Affero General Public License for more details.

 *

 * You should have received a copy of the GNU Affero General Public License

 * along with SlatePermutate.  If not, see <http://www.gnu.org/licenses/>.

 */

require_once dirname(__FILE__) . DIRECTORY_SEPARATOR . 'class.section_meeting.inc';

/**

 * \brief

 *   Represent a Section associated with a Course.

 */

{

  private $letter;	// Section letter

  private $prof;	// Professor, preserved for Section::__wakeup()

  /* meeting times, array of SectionMeeting */

  private $meetings;

  /* the section synonym which uniquely identifies this section/course combination */

  private $synonym;

  /**

   * \brief

   *   The number of credit hours this course has.

   */

  private $credit_hours;

  /**

   * \brief

   *   Construct a Section.

   *

   * \param $letter

   *   The identifier (often a letter or numeral) of this section. For

   *   CS-262-A, this would be 'a'.

   * \param $section_meetings

   *   An array of SectionMeeting objects which describe all the

   *   different types of meetings this particular section has. It

   *   will be very uncommon for a course to have more than one such

   *   meeting time for a section. For example, Calvin doesn't have

   *   this. Another example, Cedarville lists different meeting times

   *   inside of a single section. Cedarville also lists all lectures

   *   and lab meeting times directly in a section's listing.

   * \param $synonym

   *   Some schools have a unique number for each section. This field

   *   is for that number.

   * \param $credit_hours

   *   The number of credit hours this course is worth.

   */

  function __construct ($letter, array $section_meetings = array(), $synonym = NULL, $credit_hours = -1.0)

  {

    $this->letter = $letter;

    $this->meetings = $section_meetings;

    $this->synonym = $synonym;

    $this->credit_hours = (float)$credit_hours;

  }

  public function getLetter()

  {

    return $this->letter;

  }

  /**

   * \return

   *   This section's synonym -- a unique numeric identifier for this

   *   course. NULL if undefined.

   */

  public function getSynonym()

  {

    return $this->synonym;

  }

  /**

   * \brief

   *   Get an array of section meetings for this section.

   *

   * \return

   *   An array of SectionMeeting objects.

   */

  public function getMeetings()

  {

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Affero General Public License for more details.

 *

 * You should have received a copy of the GNU Affero General Public License

 * along with SlatePermutate.  If not, see <http://www.gnu.org/licenses/>.

 */

/**

 * \brief

 *   Represent a time/location that a Section meets during/at.

 *

 * A Calvin student might ask ``Why is there a need for a

 * SectionMeeting class? Doesn't every Section have a unique

 * prof/time/location?'' A Cedarville student would retort ``Huh?

 * Don't some of your classes have labs in addition to lecture? How do

 * you know that you have to go to both a lecture and lab -- and how

 * do you handle that some classes have different lecture times for

 * different days of the week?''. A Calvin section _is_ a unique

 * prof/time/location. At Cedarville, a Section refers to a prof and a

 * _set_ of time/location pairs. The generalization is to make each

 * Section support a list of meeting times/locations.

 */

class SectionMeeting

{

  private $time_start;

  private $time_end;

  private $days;

  private $location;

  private $instructor;

  /**

   * \brief

   *   Construct a SectionMeeting.

   *

   * \param $days

   *   A string of single-char day upon which a section meets. Sunday

   *   is represented with 'u', Monday with 'm', Tuesday with 't',

   *   Wednesday with 'w', Thursday with 'h', Friday with 'f', and

   *   Saturday with 's'.

   * \param $time_start

   *   The time of day when the section meeting starts. Use

   *   school_crawl_time_format() or ensure that the time is formatted

   *   in 24-hour, 0-padded, 4-digit form (HHMM).

   * \param $time_end

   *   The time of day when the section meeting ends.

   * \param $location

   *   Where the meeting occurs. Often a room number of some sort.

   * \param $type

   *   The type of meeting this is. For lectures, please use

   *   'lecture'. For labs, please use 'lab'. For others, use the

   *   school's notation.

   * \param $instructor

   *   The instructor for this section meeting.

   */

  {

    $this->days_set($days);

    $this->time_start = $time_start;

    $this->time_end = $time_end;

    $this->location = $location;

    $this->type = $type;

    $this->instructor = $instructor;

  }

  /**

   * \brief

   *   Take a days of week string and store it into our $days of week array.

   *

   * \param $days_str

   *   The days of the week in a string format. One char per

   *   day. Sun-Sat is represented with 'u', 'm', 't', 'w', 'h', 'f',

   *   's'.

   */

  private function days_set($days_str)

  {

    $this->days = array(0 => FALSE, 1 => FALSE, 2 => FALSE, 3 => FALSE, 4 => FALSE, 5 => FALSE, 6 => FALSE);

    $days_str_strlen = strlen($days_str);

    for ($i = 0; $i < $days_str_strlen; $i ++)

      $this->days[self::day_atoi($days_str[$i])] = TRUE;

  {

    return $this->time_end;

  }

  /**

   * \brief

   *   Get the type of section meeting this is.

   *

   * Examples of Section meeting types include 'lecture' and

   * 'lab'. Currently, any string may be used as a Section meeting

   * type; the possibilities for this field are controlled by the

   * crawl scripts authors' choices about what they pass to

   * SectionMeeting().

   *

   * \return

   *   A string indicating the type of section meeting.

   */

  public function type_get()

  {

    return $this->type;

  }

  /**

   * \brief

   *   Check if this section conflicts with the given section.

   *

   * \param $that

   *   The other section for which I should check for conflicts.

   * \return

   *   TRUE if there is a conflict, FALSE otherwise.

   */

  public function conflictsWith(SectionMeeting $that)

  {

    /*

     * The two sections meetings can't conflict if the start/end times

     * don't overlap. Also, use >= or <= here so that one can say ``I

     * have gym from 10 through 11 and then latin from 11 though 12''.

     */	

    if ($this->getStartTime() >= $that->getEndTime()

	|| $this->getEndTime() <= $that->getStartTime())

      {

	return FALSE;

      }

    /*

     * Now we know that the sections meetings overlap in start/end

     * times. But if they don't both meet on the same day at least

     * once, they don't conflict.

	  return TRUE;

      }

    /*

     * The sections meetings don't both share a day of the week.

     */

    return FALSE;

  }

  /**

   * \brief

   *   Return an array of JSON keys specific to this section meeting

   *   time.

   *

   * Currently, the AJAX UI doesn't recognize that a given section may

   * have multiple meeting times. Thus, we simulate this by having

   * multiple instances of the same section but just with different

   * times in the UI.

   */

  public function to_json_array()

  {

    static $daymap = array(0 => 'm', 1 => 't', 2 => 'w', 3 => 'h', 4 => 'f', 5 => 's', 6 => 'u');

    $json_array = array(

			'time_start' => $this->time_start,

			'time_end' => $this->time_end,

			'days' => array(),

			'location' => $this->location,

			'instructor' => $this->instructor,

			'type' => $this->type,

			);

    for ($day = 0; $day < 7; $day ++)

      $json_array['days'][$daymap[$day]] = $this->getDay($day);

    return $json_array;

  }

  /**

   * \brief

   *   Parse a JSON array into a SectionMeeting.

   *

   * \param $json_array

   *   The JSON array to parse.

   * \return

   *   A shiny, new SectionMeeting.

   */

  public static function from_json_array(array $json_array)

  {

    $days = '';

    foreach ($json_array['days'] as $day => $meets)

      if ($meets)

	$days .= $day;

  }

}

    $this->time_ends = array();

    $this->season = $season;

    if (strlen($year) != 4 || !is_numeric($year))

      throw new ErrorException('Attempt to construct a Semester with an invalid year. The given year is `' . $year . '\'');

    $this->year = $year;

    $this->departments = array();

    $this->department_names = array();

  }

  /**

   * \brief

   *   Add a class to this Semester.

   *

   * \param $class

   *   The class/course to add.

   */

  public function class_add(Course $class)

  {

    $class_parts = Course::parse($class->getName());

    if (!isset($class_parts['course']))

      throw new ErrorException('I was given a class with an invalid name: `' . $class->getName() . '\'');

    if (!isset($this->departments[$class_parts['department']]))

      $this->departments[$class_parts['department']] = array();

    $department =& $this->departments[$class_parts['department']];

    $department[$class_parts['course']] = $class;

  }

  /**

   * \brief

   *   Retrieve a class.

   *

   * \param $dept

   *   The class's department. 'CS' for 'CS-262'.

   * \param $class

   *   The course/class number. '262' for 'cs-262'.

   * \return

   *   A Course or NULL if not found.

   */

  public function class_get($dept, $class)

  {

    if (!isset($this->departments[$dept][$class]))

      return NULL;

    return $this->departments[$dept][$class];

   * \brief

   *   Utility function to add a section to the semester,

   *   automatically creating classes as necessary.

   *

   * Crawler functions should generally use this instead of

   * Semester::class_add().

   *

   * \param $dept

   *   The department this section belongs to.

   * \param $class

   *   The class this section belongs to.

   * \param $section

   *   The section itself.

   * \param $title

   *   The course human-friendly title.

   * \param $course_slot_id

   *   The slot of the course which this section should be added

   *   to. Use 'default' (or don't pass this parameter) if your school

   *   does not have the concept of course slots. Ask binki for help

   *   figuring this out. Course slots are a sort of

   *   inverse/complement to section_meetings.

   */

  public function section_add($dept, $class, Section $section, $title = NULL, $course_slot_id = 'default')

  {

    $dept = strtoupper($dept);

    $class = strtoupper($class);

    if (!isset($this->departments[$dept])

	|| !isset($this->departments[$dept][$class]))

      {

	$classobj = new Course($dept . '-' . $class, $title);

	$this->class_add($classobj);

      }

    else

      {

	$classobj = $this->departments[$dept][$class];

      }

    $classobj->section_add($section, $course_slot_id);

  }

  /**

   * \brief

   *   Add a section_meeting, calling Semester::section_add() as

   *   necessary.

   *

   * To be used by crawlers when parsing data which only presents one

   * section_meeting at a time. I.e., when they do tabular data right.

   * \param $dept

   *   The department this section_meeting's course belongs to.

   * \param $course

   *   The course number this section_meeting's section belongs to.

   * \param $title

   *   The course title of the given course the section_meeting or

   *   NULL. If the section has already been added, this parameter

   *   will be ignored.

   * \param $section

   *   The letter or numbers which make up the section's name.

   * \param $synonym

   *   The section synonym or NULL.

   * \param $section_meeting

   *   The SectionMeeting to be added to a section which may or may

   *   not already be in this Semester.

   * \param $course_slot_id

   *   The name of the new CourseSlot to create if the given section

   *   does not yet exist.

   * \param $credit_hours

   *   The number of credit hours of the associated course or a

   *   negative value if unknown.

   */

  public function section_meeting_add($dept, $course, $title, $section, $synonym, $section_meeting, $course_slot_id = 'default', $credit_hours = -1.0)

  {

    $dept = strtoupper($dept);

    $course = strtoupper($course);

    if (empty($this->departments[$dept][$course]))

      $course_obj = NULL;

    else

      {

	$course_obj = $this->departments[$dept][$course];

	$section_obj = $course_obj->section_get($section);

      }

    if (empty($course_obj) || empty($section_obj))

      return $this->section_add($dept, $course, new Section($section, array($section_meeting), $synonym, $credit_hours), $title, $course_slot_id);

    $section_obj->meeting_add($section_meeting);

    return;

  }

  /**

   * \brief

   *   Update the time_end.

   *

   * The time_end is a unix timestamp roughly estimating the time at

   * which a semester starts. It is used when guessing what semester a

   * user is interested in.

   * The idea is that there might be erroneous entries in a school's

   * database (

   * http://www.facebook.com/CalvinRegistrar/posts/299438720070457 )

   * which would skew the detected start time. Use statistics to

   * detect and kill outliers by using a pool of endtimes :-D.

   */

  public function time_start_pool_add($time_start)

  {

    $this->time_starts[] = $time_start;

  }

  public function time_start_get()

  {

    if (count($this->time_starts))

      {

        $times = filter_outliers($this->time_starts);

        $this->time_end = min($times);

      }

    return $this->time_start;

  }

  /**

   * \brief

   *   Get a semester's year.

   */

  public function year_get()

  {

    return $this->year;

  }

  /**

   * \brief

   *   Get a semester's season.

   */

  public function season_get()

  {

    return $this->season;

  }

  /**

   * \brief

   *   Get a semester's friendly name:

   *

   * \return

   *   A string, the semester's friendly name.

   */

  public function name_get()

elseif ($errors_fix)

  {

    foreach ($_POST['postData'] as $course)

      if (is_array($course))

	{

	  $title = '';

	  if (!empty($course['title']))

	    $title = $course['title'];

	  if (empty($course['name']))

	    $my_hc .= '    class_last = add_class();' . PHP_EOL;

	  else

	    $my_hc .= '    class_last = add_class_n(' . json_encode($course['name']) . ', ' . json_encode($title) . ');' . PHP_EOL;

	  foreach ($course as $section)

	    if (is_array($section))

	      $my_hc .= '    add_section_n(class_last, ' . json_encode($section['letter']) . ', '

		. json_encode($section['synonym']) . ', ' . json_encode($section['start']) . ', '

		. json_encode($section['end']) . ', '

		. json_encode(array('m' => !empty($section['days'][0]), 't' => !empty($section['days'][1]), 'w' => !empty($section['days'][2]),

				    'h' => !empty($section['days'][3]), 'f' => !empty($section['days'][4]),

				    's' => !empty($section['days'][5])))

		. ', ' . json_encode($section['professor']) . ', '

		. json_encode($section['location']) . ', '

		. json_encode($section['type']) . ', '

		. json_encode($section['slot']) . ', '

	  $my_hc .= PHP_EOL;

	}

  }

else

  {

    $default_courses = school_default_courses($school);

    foreach ($default_courses as $default_class)

      $my_hc .= input_course_js($default_class, '    ');

  }

$my_hc .= '    class_last = add_class();' . PHP_EOL;

if ($qtips_always || !isset($_SESSION['saw_qtips']))

  {

    $my_hc .= '    addTips();' . PHP_EOL;

    $_SESSION['saw_qtips'] = TRUE;

  }

$my_hc .= '  });

';

$inputPage->headcode_add('scheduleInput', $inputPage->script_wrap($my_hc), TRUE);

if ($school['id'] != 'default'

    && empty($_REQUEST['selectschool'])

    && empty($_REQUEST['selectsemester']))

  {

	$allClasses = new Schedule($name, $parent_schedule_id, $school, $semester);

	$errors = array();

	foreach($postData as $course)

	  {

	    /*

	     * Only add classes if the user added at least one

	     * section to the class. We know that $course['name']

	     * is not a section, so count() needs to be > 1 and

	     * we need to skip over 'name' in our loop.

	     */

	    if(is_array($course) && count($course) > 1)

	      {

		if (empty($course['title']))

		  $course['title'] = '';

		if (empty($course['credit_hours']))

		  $course['credit_hours'] = -1;

		$allClasses->addCourse($course['name'], $course['title']);

				foreach($course as $section)

				  /* Skip the section name, which isn't a section */

					if(is_array($section))

					  {

					    if ($error_string !== NULL)

					      $errors[] = $error_string;

					  }

			}

		}

		/*

		 * Tell the user that his input is erroneous and

		 * require him to fix it.

		 */

		if (count($errors))

		  {

		    $error_page = page::page_create('Process Schedule — Errors', array('qTip2'), $page_create_options);

		    $error_page->head();

		    echo '        <p>' . PHP_EOL

		      . '          You have the following errors in your input:' . PHP_EOL

		      . '        </p>' . PHP_EOL

		      . '        <ul>' . PHP_EOL;

		    foreach ($errors as $error)

		      echo '          <li>' . $error . '</li>' . PHP_EOL;

		    echo '        </ul>' . PHP_EOL

		      . '        <h3>Solving Errors</h3>' . PHP_EOL

		      . '        <ul>' . PHP_EOL

	    {

	      school_crawl_logf($school_crawl_log, 8, 'Unable to parse calvin section meeting info string into start/end/days information for '

				. implode('-', $section_id) . ': ``' . $sec_meeting_info . '\'\'');

	      $skipped_sections['invalid meeting info format'] ++;

	      /*

	       * Still add at least the course to the semester so that

	       * it shows up in autocmoplete.

	       */

	      calvin_crawl_course_add($semester, $section_id['department'], $section_id['course'], $title);

	      continue;

	    }

	  $date_start = $meeting_info_matches[1];

	  $date_end = $meeting_info_matches[2];

	  /* e.g., 'Lecture', 'Practicum' */

	  $meeting_type = school_crawl_meeting_type($meeting_info_matches[3]);

	  $days = school_crawl_days_format($school_crawl_log, explode(', ', $meeting_info_matches[5]));

	  $time_start = school_crawl_time_format(strptime($meeting_info_matches[6], '%I:%M%p'));

	  $time_end = school_crawl_time_format(strptime($meeting_info_matches[7], '%I:%M%p'));

	  $meeting_place = $meeting_info_matches[8];

	  foreach (array('date_start', 'date_end', 'meeting_type', 'days', 'time_start', 'time_end', 'meeting_place', 'meeting_type') as $var)

	    school_crawl_logf($school_crawl_log, 10, "%s:%s", $var, ${$var});

	  $date_start_time = strptime($date_start, '%m/%d/%Y');

	  $date_end_time = strptime($date_end, '%m/%d/%Y');

	  if ($date_start_time !== FALSE)

	      $date_start_time = school_crawl_gmmktime($date_start_time, -5 * 60*60);

	  if ($date_end_time !== FALSE)

	}

	}

      if (!preg_match(';Page ([0-9]+) of ([0-9]+)\</td\>$;m', $html, $pages))

	{