class Resize

class Resize extends GDImageToolkitOperationBase {
    
    /**
     * {@inheritdoc}
     */
    protected function arguments() {
        return [
            'width' => [
                'description' => 'The new width of the resized image, in pixels',
            ],
            'height' => [
                'description' => 'The new height of the resized image, in pixels',
            ],
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    protected function validateArguments(array $arguments) {
        // Assure integers for all arguments.
        $arguments['width'] = (int) round($arguments['width']);
        $arguments['height'] = (int) round($arguments['height']);
        // Fail when width or height are 0 or negative.
        if ($arguments['width'] <= 0) {
            throw new \InvalidArgumentException("Invalid width ('{$arguments['width']}') specified for the image 'resize' operation");
        }
        if ($arguments['height'] <= 0) {
            throw new \InvalidArgumentException("Invalid height ('{$arguments['height']}') specified for the image 'resize' operation");
        }
        return $arguments;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function execute(array $arguments = []) {
        // Create a new image of the required dimensions, and copy and resize
        // the original image on it with resampling.
        $original_image = $this->getToolkit()
            ->getImage();
        $data = [
            'width' => $arguments['width'],
            'height' => $arguments['height'],
            'extension' => image_type_to_extension($this->getToolkit()
                ->getType(), FALSE),
            'transparent_color' => $this->getToolkit()
                ->getTransparentColor(),
            'is_temp' => TRUE,
        ];
        if ($this->getToolkit()
            ->apply('create_new', $data)) {
            if (imagecopyresampled($this->getToolkit()
                ->getImage(), $original_image, 0, 0, 0, 0, $arguments['width'], $arguments['height'], imagesx($original_image), imagesy($original_image))) {
                return TRUE;
            }
            // In case of failure, restore the original image.
            $this->getToolkit()
                ->setImage($original_image);
        }
        return FALSE;
    }

}