class ScaleAndCrop

class ScaleAndCrop extends GDImageToolkitOperationBase {
    
    /**
     * {@inheritdoc}
     */
    protected function arguments() {
        return [
            'x' => [
                'description' => 'The horizontal offset for the start of the crop, in pixels',
                'required' => FALSE,
                'default' => NULL,
            ],
            'y' => [
                'description' => 'The vertical offset for the start the crop, in pixels',
                'required' => FALSE,
                'default' => NULL,
            ],
            'width' => [
                'description' => 'The target width, in pixels',
            ],
            'height' => [
                'description' => 'The target height, in pixels',
            ],
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    protected function validateArguments(array $arguments) {
        $actualWidth = $this->getToolkit()
            ->getWidth();
        $actualHeight = $this->getToolkit()
            ->getHeight();
        $scaleFactor = max($arguments['width'] / $actualWidth, $arguments['height'] / $actualHeight);
        $arguments['x'] = isset($arguments['x']) ? (int) round($arguments['x']) : (int) round(($actualWidth * $scaleFactor - $arguments['width']) / 2);
        $arguments['y'] = isset($arguments['y']) ? (int) round($arguments['y']) : (int) round(($actualHeight * $scaleFactor - $arguments['height']) / 2);
        $arguments['resize'] = [
            'width' => (int) round($actualWidth * $scaleFactor),
            'height' => (int) round($actualHeight * $scaleFactor),
        ];
        // Fail when width or height are 0 or negative.
        if ($arguments['width'] <= 0) {
            throw new \InvalidArgumentException("Invalid width ('{$arguments['width']}') specified for the image 'scale_and_crop' operation");
        }
        if ($arguments['height'] <= 0) {
            throw new \InvalidArgumentException("Invalid height ('{$arguments['height']}') specified for the image 'scale_and_crop' operation");
        }
        return $arguments;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function execute(array $arguments = []) {
        return $this->getToolkit()
            ->apply('resize', $arguments['resize']) && $this->getToolkit()
            ->apply('crop', $arguments);
    }

}