facade

<?php
class Book {
    private $author;
    private $title;
    function __construct($title_in, $author_in) {
        $this->author = $author_in;
        $this->title  = $title_in;
    }
    function getAuthor() {
        return $this->author;
    }
    function getTitle() {
        return $this->title;
    }
    function getAuthorAndTitle() {
        return $this->getTitle().' by '.$this->getAuthor();
    }
}
class CaseReverseFacade {
    public static function reverseStringCase($stringIn) {
        $arrayFromString = ArrayStringFunctions::stringToArray($stringIn);
        $reversedCaseArray = ArrayCaseReverse::reverseCase($arrayFromString);
        $reversedCaseString = ArrayStringFunctions::arrayToString($reversedCaseArray);
        return $reversedCaseString;
    }
}
class ArrayCaseReverse {
    private static $uppercase_array =
        array('A', 'B', 'C', 'D', 'E', 'F',
              'G', 'H', 'I', 'J', 'K', 'L',
              'M', 'N', 'O', 'P', 'Q', 'R',
              'S', 'T', 'U', 'V', 'W', 'X',
              'Y', 'Z');
    private static $lowercase_array =
        array('a', 'b', 'c', 'd', 'e', 'f',
              'g', 'h', 'i', 'j', 'k', 'l',
              'm', 'n', 'o', 'p', 'q', 'r',
              's', 't', 'u', 'v', 'w', 'x',
              'y', 'z');
    public static function reverseCase($arrayIn) {
        $array_out = array();
        for ($x = 0; $x < count($arrayIn); $x++) {
         if (in_array($arrayIn[$x], self::$uppercase_array)) {
                 $key = array_search($arrayIn[$x], self::$uppercase_array);
         $array_out[$x] = self::$lowercase_array[$key];
         } elseif (in_array($arrayIn[$x], self::$lowercase_array)) {
                 $key = array_search($arrayIn[$x], self::$lowercase_array);
         $array_out[$x] = self::$uppercase_array[$key];
             } else {
         $array_out[$x] = $arrayIn[$x];
             }
        }
    return $array_out;
    }
}
class ArrayStringFunctions {
    public static function arrayToString($arrayIn) {
      $string_out = NULL;
      foreach ($arrayIn as $oneChar) {
        $string_out .= $oneChar;
      }
      return $string_out;
    }
    public static function stringToArray($stringIn) {
      return str_split($stringIn);
    }
}
writeln('BEGIN TESTING FACADE PATTERN');
writeln('');
$book = new Book('Design Patterns', 'Gamma, Helm, Johnson, and Vlissides');
writeln('Original book title: '.$book->getTitle());
writeln('');
$bookTitleReversed = CaseReverseFacade::reverseStringCase($book->getTitle());
writeln('Reversed book title: '.$bookTitleReversed);
writeln('');
writeln('END TESTING FACADE PATTERN');
function writeln($line_in) {
  echo $line_in."&lt;br/&gt;";
}
?>