class GenerateProxyClassCommand

class GenerateProxyClassCommand extends Command {
    
    /**
     * The proxy builder.
     *
     * @var \Drupal\Component\ProxyBuilder\ProxyBuilder
     */
    protected $proxyBuilder;
    
    /**
     * Constructs a new GenerateProxyClassCommand instance.
     *
     * @param \Drupal\Component\ProxyBuilder\ProxyBuilder $proxy_builder
     *   The proxy builder.
     */
    public function __construct(ProxyBuilder $proxy_builder) {
        parent::__construct();
        $this->proxyBuilder = $proxy_builder;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function configure() {
        $this->setName('generate-proxy-class')
            ->setDefinition([
            new InputArgument('class_name', InputArgument::REQUIRED, 'The class to be proxied'),
            new InputArgument('namespace_root_path', InputArgument::REQUIRED, 'The filepath to the root of the namespace.'),
        ])
            ->setDescription('Dumps a generated proxy class into its appropriate namespace.')
            ->addUsage('\'Drupal\\Core\\Batch\\BatchStorage\' "core/lib/Drupal/Core"')
            ->addUsage('\'Drupal\\block\\BlockRepository\' "core/modules/block/src"')
            ->addUsage('\'Drupal\\my_module\\MyClass\' "modules/contrib/my_module/src"');
    }
    
    /**
     * {@inheritdoc}
     */
    protected function execute(InputInterface $input, OutputInterface $output) : int {
        $class_name = ltrim($input->getArgument('class_name'), '\\');
        $namespace_root = $input->getArgument('namespace_root_path');
        $match = [];
        preg_match('/([a-zA-Z0-9_]+\\\\[a-zA-Z0-9_]+)\\\\(.+)/', $class_name, $match);
        if ($match) {
            $root_namespace = $match[1];
            $rest_fqcn = $match[2];
            $proxy_filename = $namespace_root . '/ProxyClass/' . str_replace('\\', '/', $rest_fqcn) . '.php';
            $proxy_class_name = $root_namespace . '\\ProxyClass\\' . $rest_fqcn;
            $proxy_class_string = $this->proxyBuilder
                ->build($class_name);
            $file_string = <<<EOF
<?php
// phpcs:ignoreFile

/**
 * This file was generated via php core/scripts/generate-proxy-class.php '{<span class="php-variable">$class_name</span>}' "{<span class="php-variable">$namespace_root</span>}".
 */
{{ proxy_class_string }}
EOF;
            $file_string = str_replace([
                '{{ proxy_class_name }}',
                '{{ proxy_class_string }}',
            ], [
                $proxy_class_name,
                $proxy_class_string,
            ], $file_string);
            mkdir(dirname($proxy_filename), 0775, TRUE);
            file_put_contents($proxy_filename, $file_string);
            $output->writeln(sprintf('Proxy of class %s written to %s', $class_name, $proxy_filename));
        }
        return 0;
    }

}