index.php

<?php 

class FakeImage {
  function rotate($deg) {
    echo "Rotating $deg degrees\n";
    return $this;
  }
  function mirror(){
    echo "Mirroring\n";
    return $this;
  }
  function copy() {
    echo "Copying\n";
    return $this;
  }
  function saveToFile($path) {
    echo "Saving image to $path\n";
    return $this;
  }
}

class WideImage_Operation_ExifOrient
{
  // orientation constants
  const MIRROR = 2;
  const ROTATE_180 = 3;
  const ROTATE_180_MIRROR = 4;
  const ROTATE_90_MIRROR = 5;
  const ROTATE_90 = 6;
  const ROTATE_270_MIRROR = 7;
  const ROTATE_270 = 8;
  
  function execute($image, $orientation)
  {
    if (!isset($image))  throw new Exception('No image given');
    if (!isset($orientation))  throw new Exception('No orientation given');
    
    switch ($orientation) {
      case self::MIRROR:
        return $image->mirror();

      case self::ROTATE_180:
        return $image->rotate(180);

      case self::ROTATE_180_MIRROR:
        return $image->rotate(180)->mirror();

      case self::ROTATE_90_MIRROR:
        return $image->rotate(90)->mirror();
        
      case self::ROTATE_90:
        return $image->rotate(90);
        
      case self::ROTATE_270_MIRROR:
        return $image->rotate(-90)->mirror();
        
      case self::ROTATE_270:
        return $image->rotate(-90);
        
      default: 
        return $image->copy();
    }
  }
}

// fake data for testing
$exif = array('Orientation' => 7);
$image = new FakeImage();
$imageWithText = "/tmp/image.jpg";

// use the class
$transformation = new WideImage_Operation_ExifOrient();
$transformation->execute($image, $exif['Orientation']);
$image->saveToFile($imageWithText);