<?php
/*PLEASE DO NOT EDIT THIS CODE*/
/*This code was generated using the UMPLE 1.35.0.7523.c616a4dce modeling language!*/

class Mentor
{

  //------------------------
  // MEMBER VARIABLES
  //------------------------

  //Mentor Attributes
  private $name;

  //Mentor Associations
  private $students;

  //------------------------
  // CONSTRUCTOR
  //------------------------

  public function __construct($aName)
  {
    $this->name = $aName;
    $this->students = array();
  }

  //------------------------
  // INTERFACE
  //------------------------

  public function setName($aName)
  {
    $wasSet = false;
    $this->name = $aName;
    $wasSet = true;
    return $wasSet;
  }

  public function getName()
  {
    return $this->name;
  }

  public function getStudent_index($index)
  {
    $aStudent = $this->students[$index];
    return $aStudent;
  }

  public function getStudents()
  {
    $newStudents = $this->students;
    return $newStudents;
  }

  public function numberOfStudents()
  {
    $number = count($this->students);
    return $number;
  }

  public function hasStudents()
  {
    $has = $this->numberOfStudents() > 0;
    return $has;
  }

  public function indexOfStudent($aStudent)
  {
    $wasFound = false;
    $index = 0;
    foreach($this->students as $student)
    {
      if ($student->equals($aStudent))
      {
        $wasFound = true;
        break;
      }
      $index += 1;
    }
    $index = $wasFound ? $index : -1;
    return $index;
  }

  public function isNumberOfStudentsValid()
  {
    $isValid = $this->numberOfStudents() >= self::minimumNumberOfStudents() && $this->numberOfStudents() <= self::maximumNumberOfStudents();
    return $isValid;
  }

  public static function requiredNumberOfStudents()
  {
    return 4;
  }

  public static function minimumNumberOfStudents()
  {
    return 4;
  }

  public static function maximumNumberOfStudents()
  {
    return 4;
  }

  public function addStudentVia($aNumber)
  {
    if ($this->numberOfStudents() >= self::maximumNumberOfStudents())
    {
      return null;
    }
    else
    {
      return new Student($aNumber, $this);
    }
  }

  public function addStudent($aStudent)
  {
    $wasAdded = false;
    if ($this->indexOfStudent($aStudent) !== -1) { return false; }
    if ($this->numberOfStudents() >= self::maximumNumberOfStudents())
    {
      return $wasAdded;
    }

    $existingMentor = $aStudent->getMentor();
    $isNewMentor = $existingMentor != null && $this !== $existingMentor;

    if ($isNewMentor && $existingMentor->numberOfStudents() <= self::minimumNumberOfStudents())
    {
      return $wasAdded;
    }

    if ($isNewMentor)
    {
      $aStudent->setMentor($this);
    }
    else
    {
      $this->students[] = $aStudent;
    }
    $wasAdded = true;
    return $wasAdded;
  }

  public function removeStudent($aStudent)
  {
    $wasRemoved = false;
    //Unable to remove aStudent, as it must always have a mentor
    if ($this === $aStudent->getMentor())
    {
      return $wasRemoved;
    }

    //mentor already at minimum (4)
    if ($this->numberOfStudents() <= self::minimumNumberOfStudents())
    {
      return $wasRemoved;
    }

    unset($this->students[$this->indexOfStudent($aStudent)]);
    $this->students = array_values($this->students);
    $wasRemoved = true;
    return $wasRemoved;
  }

  public function equals($compareTo)
  {
    return $this == $compareTo;
  }

  public function delete()
  {
    foreach ($this->students as $aStudent)
    {
      $aStudent->delete();
    }
  }

}
?>
<?php
/*PLEASE DO NOT EDIT THIS CODE*/
/*This code was generated using the UMPLE 1.35.0.7523.c616a4dce modeling language!*/

class Student
{

  //------------------------
  // MEMBER VARIABLES
  //------------------------

  //Student Attributes
  private $number;

  //Student Associations
  private $mentor;

  //------------------------
  // CONSTRUCTOR
  //------------------------

  public function __construct($aNumber, $aMentor)
  {
    $this->number = $aNumber;
    $didAddMentor = $this->setMentor($aMentor);
    if (!$didAddMentor)
    {
      throw new Exception("Unable to create student due to mentor. See https://manual.umple.org?RE002ViolationofAssociationMultiplicity.html");
    }
  }

  //------------------------
  // INTERFACE
  //------------------------

  public function setNumber($aNumber)
  {
    $wasSet = false;
    $this->number = $aNumber;
    $wasSet = true;
    return $wasSet;
  }

  public function getNumber()
  {
    return $this->number;
  }

  public function getMentor()
  {
    return $this->mentor;
  }

  public function setMentor($aMentor)
  {
    $wasSet = false;
    //Must provide mentor to student
    if ($aMentor == null)
    {
      return $wasSet;
    }

    //mentor already at maximum (4)
    if ($aMentor->numberOfStudents() >= Mentor::maximumNumberOfStudents())
    {
      return $wasSet;
    }
    
    $existingMentor = $this->mentor;
    $this->mentor = $aMentor;
    if ($existingMentor != null && $existingMentor != $aMentor)
    {
      $didRemove = $existingMentor->removeStudent($this);
      if (!$didRemove)
      {
        $this->mentor = $existingMentor;
        return $wasSet;
      }
    }
    $this->mentor->addStudent($this);
    $wasSet = true;
    return $wasSet;
  }

  public function equals($compareTo)
  {
    return $this == $compareTo;
  }

  public function delete()
  {
    $placeholderMentor = $this->mentor;
    $this->mentor = null;
    $placeholderMentor->removeStudent($this);
  }

}
?>