xenon54

<?php

class thumbnail {



	private $types = array(

		IMAGETYPE_JPEG => 'jpeg',

		IMAGETYPE_GIF => 'gif',

		IMAGETYPE_BMP => 'wbmp',

		IMAGETYPE_PNG => 'png'

	);



	private $thumbnaildir = './';



	public $maxWidth = 0;

	public $maxHeight = 0;





	public function __construct($thumbnaildir=NULL) {



		if (FALSE === extension_loaded('gd')) {

			throw new Exception('gd must be compiled to use this class.');

		}



		if (FALSE === extension_loaded('exif')) {

			throw new Exception('libexif must be compiled to use this class.');

		}



		$this->thumbnaildir = $thumbnaildir;



	}



	public function execute($filename) {



		if (FALSE === file_exists($filename)) {

			throw new Exception('No such file.');

		}



		if (FALSE === $type = exif_imagetype($filename)) {

			throw new Exception('File is not an image.');

		}





		if (FALSE === array_key_exists($type, $this->types)) {

			throw new Exception('Image type is not supported by this class.');

		} else {

			$type = $this->types[$type];

		}



		try {

			$this->validation();

			$result = $this->resize($filename, $type);

		} catch ( Exception $e ) {

			throw $e;

		}



		return $result;

	}



	private function resize($filename, $type) {



		if (0 === $this->maxHeight && 0 === $this->maxWidth) {

			return TRUE;

		}



		list($width, $height) = getimagesize($filename);



		if ($width <= $this->maxWidth && $height <= $this->maxHeight) {

			return TRUE;

		}



		if ($width > $height) {

			$thumbnail_width = $this->maxWidth;

			$thumbnail_height = (int) ($this->maxWidth * $height / $width);

		} else {

			$thumbnail_width = (int) ($this->maxHeight * $width / $height);

			$thumbnail_height = $this->maxHeight;

		}



		$read = 'imagecreatefrom' . $type;

		$write = 'image' . $type;



		if (FALSE === function_exists($write) ) {

			throw new Exception('Image type is not supported by your GD library.');

		}



		if (FALSE === $img = $read($filename) ) {

			throw new Exception('An exception occured while opening original file.');

		}



		if ('gif' === $type) {

			$des = imagecreate($thumbnail_width, $thumbnail_height);

			$resize = 'imagecopyresized';

		} else {

			$des = imagecreatetruecolor($thumbnail_width, $thumbnail_height);

			$resize = 'imagecopyresampled';

		}



		if ('png' === $type) {



			if (FALSE === imagealphablending($des, FALSE) ) {

				throw new Exception('Enable to activate full alpha information.');

			}

			if (FALSE === imagesavealpha($des, TRUE)) {

				throw new Exception('Enable to activate full alpha information.');

			}

		}



		if (FALSE === $resize($des, $img, 0, 0, 0, 0, $thumbnail_width, $thumbnail_height, $width, $height)) {

			throw new Exception('An exception occured while resizing the original file.');

		}



		if (FALSE === $write($des, $this->thumbnaildir . '/' . $filename)) {

			throw new Exception('An exception occured while writing thumbnail file.');

		}



		return TRUE;

	}





	private function validation() {



		if (FALSE === is_writable($this->thumbnaildir)) {

			throw new Exception('Thumbnails directory is not writable.');

		}



		if (FALSE === is_int($this->maxWidth) || FALSE === is_int($this->maxHeight)) {

			throw new Exception('Maximum dimensions must be integer.');

		}



		if (0 > $this->maxWidth || 0 > $this->maxHeight) {

			throw new Exception('Maximum dimensions must be positive integer.');

		}

	}





}



// Exemple d'utilisation

try {

	$thumb = new thumbnail('./thumbs/');

	$thumb->maxWidth = 80;

	$thumb->maxHeight = 60;

	$thumb->execute('image.png');

} catch (Exception $e) {



	echo '';

	echo 'Error message: ' , $e->getMessage() , '';

	echo 'Error code: ' , $e->getCode() , '';

	echo 'Script Name: ' , $e->getFile() , '';

	echo 'Line Number: ' , $e->getLine() , ''; 

}

?>