class YamlFileLoader

class YamlFileLoader {
    private const DEFAULTS_KEYWORDS = [
        'public' => 'public',
        'tags' => 'tags',
        'autowire' => 'autowire',
    ];
    
    /**
     * @var \Drupal\Core\DependencyInjection\ContainerBuilder $container
     */
    protected $container;
    
    /**
     * File cache object.
     *
     * @var \Drupal\Component\FileCache\FileCacheInterface
     */
    protected $fileCache;
    public function __construct(ContainerBuilder $container) {
        $this->container = $container;
        $this->fileCache = FileCacheFactory::get('container_yaml_loader');
    }
    
    /**
     * Loads a Yaml file.
     *
     * @param mixed $file
     *   The resource
     */
    public function load($file) {
        // Load from the file cache, fall back to loading the file.
        $content = $this->fileCache
            ->get($file);
        if (!$content) {
            $content = $this->loadFile($file);
            $this->fileCache
                ->set($file, $content);
        }
        // Not supported.
        
        //$this->container->addResource(new FileResource($path));
        // empty file
        if (null === $content) {
            return;
        }
        // imports
        // Not supported.
        
        //$this->parseImports($content, $file);
        // parameters
        if (isset($content['parameters'])) {
            if (!is_array($content['parameters'])) {
                throw new InvalidArgumentException(sprintf('The "parameters" key should contain an array in %s. Check your YAML syntax.', $file));
            }
            foreach ($content['parameters'] as $key => $value) {
                $this->container
                    ->setParameter($key, $this->resolveServices($value));
            }
        }
        // extensions
        // Not supported.
        
        //$this->loadFromExtensions($content);
        // services
        $this->parseDefinitions($content, $file);
    }
    
    /**
     * Parses definitions
     *
     * @param array $content
     * @param string $file
     */
    private function parseDefinitions($content, $file) {
        if (!isset($content['services'])) {
            return;
        }
        if (!is_array($content['services'])) {
            throw new InvalidArgumentException(sprintf('The "services" key should contain an array in %s. Check your YAML syntax.', $file));
        }
        // Some extensions split up their dependencies into multiple files.
        if (isset($content['_provider'])) {
            $provider = $content['_provider'];
        }
        else {
            $basename = basename($file);
            [
                $provider,
            ] = explode('.', $basename, 2);
        }
        $defaults = $this->parseDefaults($content, $file);
        $defaults['tags'][] = [
            'name' => '_provider',
            'provider' => $provider,
        ];
        foreach ($content['services'] as $id => $service) {
            $this->parseDefinition($id, $service, $file, $defaults);
        }
    }
    
    /**
     * @param array  $content
     * @param string $file
     *
     * @return array
     *
     * @throws InvalidArgumentException
     */
    private function parseDefaults(array &$content, string $file) : array {
        if (!\array_key_exists('_defaults', $content['services'])) {
            return [];
        }
        $defaults = $content['services']['_defaults'];
        unset($content['services']['_defaults']);
        if (!\is_array($defaults)) {
            throw new InvalidArgumentException(sprintf('Service "_defaults" key must be an array, "%s" given in "%s".', \gettype($defaults), $file));
        }
        foreach ($defaults as $key => $default) {
            if (!isset(self::DEFAULTS_KEYWORDS[$key])) {
                throw new InvalidArgumentException(sprintf('The configuration key "%s" cannot be used to define a default value in "%s". Allowed keys are "%s".', $key, $file, implode('", "', self::DEFAULTS_KEYWORDS)));
            }
        }
        if (isset($defaults['tags'])) {
            if (!\is_array($tags = $defaults['tags'])) {
                throw new InvalidArgumentException(sprintf('Parameter "tags" in "_defaults" must be an array in "%s". Check your YAML syntax.', $file));
            }
            foreach ($tags as $tag) {
                if (!\is_array($tag)) {
                    $tag = [
                        'name' => $tag,
                    ];
                }
                if (!isset($tag['name'])) {
                    throw new InvalidArgumentException(sprintf('A "tags" entry in "_defaults" is missing a "name" key in "%s".', $file));
                }
                $name = $tag['name'];
                unset($tag['name']);
                if (!\is_string($name) || '' === $name) {
                    throw new InvalidArgumentException(sprintf('The tag name in "_defaults" must be a non-empty string in "%s".', $file));
                }
                foreach ($tag as $attribute => $value) {
                    if (!is_scalar($value) && null !== $value) {
                        throw new InvalidArgumentException(sprintf('Tag "%s", attribute "%s" in "_defaults" must be of a scalar-type in "%s". Check your YAML syntax.', $name, $attribute, $file));
                    }
                }
            }
        }
        return $defaults;
    }
    
    /**
     * Parses a definition.
     *
     * @param string $id
     * @param array $service
     * @param string $file
     * @param array $defaults
     *
     * @throws InvalidArgumentException
     *   When tags are invalid.
     */
    private function parseDefinition(string $id, $service, string $file, array $defaults) {
        if (\is_string($service) && 0 === strpos($service, '@')) {
            $this->container
                ->setAlias($id, $alias = new Alias(substr($service, 1)));
            if (isset($defaults['public'])) {
                $alias->setPublic($defaults['public']);
            }
            return;
        }
        if (null === $service) {
            $service = [];
        }
        if (!is_array($service)) {
            throw new InvalidArgumentException(sprintf('A service definition must be an array or a string starting with "@" but %s found for service "%s" in %s. Check your YAML syntax.', gettype($service), $id, $file));
        }
        if (isset($service['alias'])) {
            $this->container
                ->setAlias($id, $alias = new Alias($service['alias']));
            if (isset($service['public'])) {
                $alias->setPublic($service['public']);
            }
            elseif (isset($defaults['public'])) {
                $alias->setPublic($defaults['public']);
            }
            if (array_key_exists('deprecated', $service)) {
                if (method_exists($alias, 'getDeprecation')) {
                    $deprecation = \is_array($service['deprecated']) ? $service['deprecated'] : [
                        'message' => $service['deprecated'],
                    ];
                    $alias->setDeprecated($deprecation['package'] ?? '', $deprecation['version'] ?? '', $deprecation['message']);
                }
                else {
                    // @todo Remove when we no longer support Symfony 4 in
                    // https://www.drupal.org/project/drupal/issues/3197729
                    $alias->setDeprecated(true, $service['deprecated']);
                }
            }
            return;
        }
        if (isset($service['parent'])) {
            $definition = new ChildDefinition($service['parent']);
        }
        else {
            $definition = new Definition();
            // Drupal services are public by default.
            $definition->setPublic(true);
            if (isset($defaults['public'])) {
                $definition->setPublic($defaults['public']);
            }
            if (isset($defaults['autowire'])) {
                $definition->setAutowired($defaults['autowire']);
            }
            $definition->setChanges([]);
        }
        if (isset($service['class'])) {
            $definition->setClass($service['class']);
        }
        if (isset($service['shared'])) {
            $definition->setShared($service['shared']);
        }
        if (isset($service['synthetic'])) {
            $definition->setSynthetic($service['synthetic']);
        }
        if (isset($service['lazy'])) {
            $definition->setLazy($service['lazy']);
        }
        if (isset($service['public'])) {
            $definition->setPublic($service['public']);
        }
        if (isset($service['abstract'])) {
            $definition->setAbstract($service['abstract']);
        }
        if (array_key_exists('deprecated', $service)) {
            if (method_exists($definition, 'getDeprecation')) {
                $deprecation = \is_array($service['deprecated']) ? $service['deprecated'] : [
                    'message' => $service['deprecated'],
                ];
                $definition->setDeprecated($deprecation['package'] ?? '', $deprecation['version'] ?? '', $deprecation['message']);
            }
            else {
                // @todo Remove when we no longer support Symfony 4 in
                // https://www.drupal.org/project/drupal/issues/3197729
                $definition->setDeprecated(true, $service['deprecated']);
            }
        }
        if (isset($service['factory'])) {
            if (is_string($service['factory'])) {
                if (strpos($service['factory'], ':') !== false && strpos($service['factory'], '::') === false) {
                    $parts = explode(':', $service['factory']);
                    $definition->setFactory(array(
                        $this->resolveServices('@' . $parts[0]),
                        $parts[1],
                    ));
                }
                else {
                    $definition->setFactory($service['factory']);
                }
            }
            else {
                $definition->setFactory(array(
                    $this->resolveServices($service['factory'][0]),
                    $service['factory'][1],
                ));
            }
        }
        if (isset($service['factory_class'])) {
            $definition->setFactory($service['factory_class']);
        }
        if (isset($service['factory_method'])) {
            $definition->setFactory($service['factory_method']);
        }
        if (isset($service['factory_service'])) {
            $definition->setFactory($service['factory_service']);
        }
        if (isset($service['file'])) {
            $definition->setFile($service['file']);
        }
        if (isset($service['arguments'])) {
            $definition->setArguments($this->resolveServices($service['arguments']));
        }
        if (isset($service['properties'])) {
            $definition->setProperties($this->resolveServices($service['properties']));
        }
        if (isset($service['configurator'])) {
            if (is_string($service['configurator'])) {
                $definition->setConfigurator($service['configurator']);
            }
            else {
                $definition->setConfigurator(array(
                    $this->resolveServices($service['configurator'][0]),
                    $service['configurator'][1],
                ));
            }
        }
        if (isset($service['calls'])) {
            if (!is_array($service['calls'])) {
                throw new InvalidArgumentException(sprintf('Parameter "calls" must be an array for service "%s" in %s. Check your YAML syntax.', $id, $file));
            }
            foreach ($service['calls'] as $call) {
                if (isset($call['method'])) {
                    $method = $call['method'];
                    $args = isset($call['arguments']) ? $this->resolveServices($call['arguments']) : array();
                }
                else {
                    $method = $call[0];
                    $args = isset($call[1]) ? $this->resolveServices($call[1]) : array();
                }
                $definition->addMethodCall($method, $args);
            }
        }
        $tags = $service['tags'] ?? [];
        if (!\is_array($tags)) {
            throw new InvalidArgumentException(sprintf('Parameter "tags" must be an array for service "%s" in "%s". Check your YAML syntax.', $id, $file));
        }
        if (isset($defaults['tags'])) {
            $tags = array_merge($tags, $defaults['tags']);
        }
        foreach ($tags as $tag) {
            if (!\is_array($tag)) {
                $tag = [
                    'name' => $tag,
                ];
            }
            if (!isset($tag['name'])) {
                throw new InvalidArgumentException(sprintf('A "tags" entry is missing a "name" key for service "%s" in "%s".', $id, $file));
            }
            $name = $tag['name'];
            unset($tag['name']);
            if (!\is_string($name) || '' === $name) {
                throw new InvalidArgumentException(sprintf('The tag name for service "%s" in "%s" must be a non-empty string.', $id, $file));
            }
            foreach ($tag as $attribute => $value) {
                if (!is_scalar($value) && null !== $value) {
                    throw new InvalidArgumentException(sprintf('A "tags" attribute must be of a scalar-type for service "%s", tag "%s", attribute "%s" in "%s". Check your YAML syntax.', $id, $name, $attribute, $file));
                }
            }
            $definition->addTag($name, $tag);
        }
        if (isset($service['decorates'])) {
            $renameId = $service['decoration_inner_name'] ?? null;
            $priority = $service['decoration_priority'] ?? 0;
            $definition->setDecoratedService($service['decorates'], $renameId, $priority);
        }
        if (isset($service['autowire'])) {
            $definition->setAutowired($service['autowire']);
        }
        $this->container
            ->setDefinition($id, $definition);
    }
    
    /**
     * Loads a YAML file.
     *
     * @param string $file
     *
     * @return array The file content
     *
     * @throws InvalidArgumentException
     *   When the given file is not a local file or when it does not exist.
     */
    protected function loadFile($file) {
        if (!stream_is_local($file)) {
            throw new InvalidArgumentException(sprintf('This is not a local file "%s".', $file));
        }
        if (!file_exists($file)) {
            throw new InvalidArgumentException(sprintf('The service file "%s" is not valid.', $file));
        }
        return $this->validate(Yaml::decode(file_get_contents($file)), $file);
    }
    
    /**
     * Validates a YAML file.
     *
     * @param mixed $content
     * @param string $file
     *
     * @return array
     *
     * @throws InvalidArgumentException
     *   When service file is not valid.
     */
    private function validate($content, $file) {
        if (null === $content) {
            return $content;
        }
        if (!is_array($content)) {
            throw new InvalidArgumentException(sprintf('The service file "%s" is not valid. It should contain an array. Check your YAML syntax.', $file));
        }
        if ($invalid_keys = array_diff_key($content, array(
            'parameters' => 1,
            'services' => 1,
        ))) {
            throw new InvalidArgumentException(sprintf('The service file "%s" is not valid: it contains invalid keys %s. Services have to be added under "services" and Parameters under "parameters".', $file, $invalid_keys));
        }
        return $content;
    }
    
    /**
     * Resolves services.
     *
     * @param string|array $value
     *
     * @return array|string|Reference
     */
    private function resolveServices($value) {
        if (is_array($value)) {
            $value = array_map(array(
                $this,
                'resolveServices',
            ), $value);
        }
        elseif (is_string($value) && 0 === strpos($value, '@=')) {
            // Not supported.
            
            //return new Expression(substr($value, 2));
            throw new InvalidArgumentException(sprintf("'%s' is an Expression, but expressions are not supported.", $value));
        }
        elseif (is_string($value) && 0 === strpos($value, '@')) {
            if (0 === strpos($value, '@@')) {
                $value = substr($value, 1);
                $invalidBehavior = null;
            }
            elseif (0 === strpos($value, '@?')) {
                $value = substr($value, 2);
                $invalidBehavior = ContainerInterface::IGNORE_ON_INVALID_REFERENCE;
            }
            else {
                $value = substr($value, 1);
                $invalidBehavior = ContainerInterface::EXCEPTION_ON_INVALID_REFERENCE;
            }
            if ('=' === substr($value, -1)) {
                $value = substr($value, 0, -1);
                $strict = false;
            }
            else {
                $strict = true;
            }
            if (null !== $invalidBehavior) {
                $value = new Reference($value, $invalidBehavior, $strict);
            }
        }
        return $value;
    }

}