<?php

  include_once('OnTheBookShelf.php'); 

  class SeveralBooks extends OnTheBookShelf {

    private $oneBooks = array();
    private $bookCount;

    public function __construct() {
      $this->setBookCount(0);
    }

    public function getBookCount() {
      return $this->bookCount;
    }
    public function setBookCount($newCount) {
      $this->bookCount = $newCount;
    }

    public function getBookInfo($bookToGet) {	
      if ($bookToGet <= $this->bookCount) {
        return $this->oneBooks[$bookToGet]->getBookInfo(1);
      } else {
        return FALSE;
      }
    }

    public function addBook($oneBook) {
      $this->setBookCount($this->getBookCount() + 1);
      $this->oneBooks[$this->getBookCount()] = $oneBook;
      return $this->getBookCount();
    }

    public function removeBook($oneBook) {
      $counter = 0;
      while (++$counter <= $this->getBookCount()) {
        if ($oneBook->getBookInfo(1) == 
          $this->oneBooks[$counter]->getBookInfo(1)) {
          for ($x = $counter; $x < $this->getBookCount(); $x++) {
            $this->oneBooks[$x] = $this->oneBooks[$x + 1];
          }
          $this->setBookCount($this->getBookCount() - 1);
        }
      }
      return $this->getBookCount();
    }

  }
?>