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ImageHandler.php

<?php
namespace GdWrapper;

interface Image {
	public function getPath();
	public function getWidth();
	public function getHeight();
	public function getType();
}

class ImageInfo {
	private $width;
	private $height;
	
	public function __consctuct($path) {
		$dimensions = getimagesize($path);
		$this->width = $dimensions[0];
		$this->height = $dimensions[1];
	}
	
	public function getWidth() {
		return $this->width;
	}
	
	public function getHeight() {
		return $this->height;
	}
}

class AbstractImage extends SplFileInfo implements Image {
	private $width:
	private $height;
	private $info;
	private $resource;
	
	public function __clone() {
		$this->resource = clone $this->resource;
	}
	
	private function getInfo() {
		if($this->info === null) {
			$this->info = new ImageInfo($this->getPath());
		}
		return $this->info;
	}
	
	public function getWidth() {
		return $this->getInfo()->getWidth();
	}
	
	public function getHeight() {
		return $this->getInfo()->getHeight();
	}

	protected function setResource(ImageResource $resource) {
		$this->resource = $resource;
	}
	
	public function getResource() {
		return $this->resource;
	}

	public static function factory($path) {
		$type = pathinfo($path, FILEINFO_PATH);
		$className = __NAMESPACE__ . "\\Image" . ucfirst(strtolower($type));
		try {
			$reflection = new \ReflectionClass($className);
			return $reflection->newInstance($path);
		} catch(\ReflectionException $e) {
			throw new UnsupportedFileExtensionException("Extension ${path} not supported!");
		}
	}
}

abstract class ImageResource {
	const IMAGE_QUALITY_MAX = 100;
	const IMAGE_QUALITY_HIGH = 90;
	const IMAGE_QUALITY_MED = 75;
	const IMAGE_QUALITY_LOW = 50;
	const IMAGE_QUALITY_DRAFT = 30;
	
	private $resource;
	
	final protected function setRaw($resource) {
		$this->resource = $resource;
	}
	
	final public function __clone() {
		ob_start();
		imagegd2($this->resource);
		$this->resource = imagecreatefromstring(ob_get_clean());
	}
	
	public function raw() {
		return $resource;
	}
	
	public function output($filename = null, $quality = self::IMAGE_QUALITY_MAX, 
			$addtionalParameters = null) {
		$args = func_get_args();
		call_user_func_array($thi->getOutputFn(), $args);
	}
	
	abstract protected function getOutputFn();
	
	final public __destruct() {
		if($this->resource !== null)
			imagedestroy($this->resource);
	}
}

class ImageJpegResource extends ImageResource {
	public function __construct($path) {
		$this->setRaw(imagecreatefromjpeg($path));
	}
	
	protected function getOutputFn() {
		return 'imagejpeg';
	}
}

class ImagePngResource extends ImageResource {
	public function __construct($path) {
		$this->setRaw(imagecreatefrompng($path));
	}
	
	protected function getOutputFn() {
		return 'imagepng';
	}
}

class ImageGifResource extends ImageResource {
	public function __construct($path) {
		$this->setRaw(imagecreatefromgif($path));
	}
	
	protected function getOutputFn() {
		return 'imagegif';
	}
}

class ImageJpeg extends AbstractImage {
	public function __construct($path) {
		parent::__construct($path);
		$this->setResource(new ImageJpegResource($path));
	}
}

class ImageJpg extends ImageJpeg {
	public function getType() {
		return 'jpeg';
	}
}

class ImagePng extends AbstractImage {
	public function __construct($path) {
		parent::__construct($path);
		$this->setResource(new ImagePngResource($path));
	}
}

class ImageGif extends AbstractImage {
    public function __construct($path) {
		parent::__construct($path);
		$this->setResource(new ImageGifResource($path));
	}
}