class Recipe

final class Recipe {
    const COMPOSER_PROJECT_TYPE = 'drupal-recipe';
    
    /**
     * @param string $name
     *   The human-readable name of the recipe.
     * @param string $description
     *   A short description of the recipe.
     * @param string $type
     *   The recipe type.
     * @param \Drupal\Core\Recipe\RecipeConfigurator $recipes
     *   The recipe configurator, which lists the recipes that will be applied
     *   before this one.
     * @param \Drupal\Core\Recipe\InstallConfigurator $install
     *   The install configurator, which lists the extensions this recipe will
     *   install.
     * @param \Drupal\Core\Recipe\ConfigConfigurator $config
     *   The config configurator, which lists the config that this recipe will
     *   install, and what config actions will be taken.
     * @param \Drupal\Core\Recipe\InputConfigurator $input
     *   The input configurator, which collects any input values used by the
     *   recipe.
     * @param \Drupal\Core\DefaultContent\Finder $content
     *   The default content finder.
     * @param string $path
     *   The recipe's path.
     */
    public function __construct(string $name, string $description, string $type, RecipeConfigurator $recipes, InstallConfigurator $install, ConfigConfigurator $config, InputConfigurator $input, Finder $content, string $path) {
    }
    
    /**
     * Creates a recipe object from the provided path.
     *
     * @param string $path
     *   The path to a recipe.
     *
     * @return static
     *   The Recipe object.
     */
    public static function createFromDirectory(string $path) : static {
        $recipe_data = self::parse($path . '/recipe.yml');
        $recipes = new RecipeConfigurator(is_array($recipe_data['recipes']) ? $recipe_data['recipes'] : [], dirname($path));
        $install = new InstallConfigurator($recipe_data['install'], \Drupal::service('extension.list.module'), \Drupal::service('extension.list.theme'));
        $config = new ConfigConfigurator($recipe_data['config'], $path, \Drupal::service('config.storage'));
        $input = new InputConfigurator($recipe_data['input'] ?? [], $recipes, basename($path), \Drupal::typedDataManager());
        $content = new Finder($path . '/content');
        return new static($recipe_data['name'], $recipe_data['description'], $recipe_data['type'], $recipes, $install, $config, $input, $content, $path);
    }
    
    /**
     * Parses and validates a recipe.yml file.
     *
     * @param string $file
     *   The path of a recipe.yml file.
     *
     * @return mixed[]
     *   The parsed and validated data from the file.
     *
     * @throws \Drupal\Core\Recipe\RecipeFileException
     *   Thrown if the recipe.yml file is unreadable, invalid, or cannot be
     *   validated.
     */
    private static function parse(string $file) : array {
        if (!file_exists($file)) {
            throw new RecipeFileException($file, "There is no {$file} file");
        }
        $recipe_contents = file_get_contents($file);
        if (!$recipe_contents) {
            throw new RecipeFileException($file, "{$file} does not exist or could not be read.");
        }
        // Certain parts of our validation need to be able to scan for other
        // recipes.
        // @see ::validateRecipeExists()
        // @see ::validateConfigActions()
        $include_path = dirname($file, 2);
        $constraints = new Collection([
            'name' => new Required([
                new Type('string'),
                new NotBlank(),
                // Matching `type: label` in core.data_types.schema.yml.
new RegexConstraint(pattern: '/([^\\PC])/u', message: 'Recipe names cannot span multiple lines or contain control characters.', match: FALSE),
            ]),
            'description' => new Optional([
                new NotBlank(),
                // Matching `type: text` in core.data_types.schema.yml.
new RegexConstraint(pattern: '/([^\\PC\\x09\\x0a\\x0d])/u', message: 'The recipe description cannot contain control characters, only visible characters.', match: FALSE),
            ]),
            'type' => new Optional([
                new Type('string'),
                new NotBlank(),
                // Matching `type: label` in core.data_types.schema.yml.
new RegexConstraint(pattern: '/([^\\PC])/u', message: 'Recipe type cannot span multiple lines or contain control characters.', match: FALSE),
            ]),
            'recipes' => new Optional([
                new All([
                    new Type('string'),
                    new NotBlank(),
                    // If recipe depends on itself, ::validateRecipeExists() will set off
                    // an infinite loop. We can avoid that by skipping that validation if
                    // the recipe depends on itself, which is what Sequentially does.
new Sequentially([
                        new NotIdenticalTo(value: basename(dirname($file)), message: 'The {{ compared_value }} recipe cannot depend on itself.'),
                        new Callback(callback: self::validateRecipeExists(...), payload: $include_path),
                    ]),
                ]),
            ]),
            // @todo https://www.drupal.org/i/3424603 Validate the corresponding
            //   import.
'install' => new Optional([
                new All([
                    new Type('string'),
                    new Sequentially([
                        new NotBlank(),
                        new Callback(self::validateExtensionIsAvailable(...)),
                    ]),
                ]),
            ]),
            'input' => new Optional([
                new Type('associative_array'),
                new All([
                    new Collection(fields: [
                        // Every input definition must have a description.
'description' => [
                            new Type('string'),
                            new NotBlank(),
                        ],
                        // There can be an optional set of constraints, which is an
                        // associative array of arrays, as in config schema.
'constraints' => new Optional([
                            new Type('associative_array'),
                        ]),
                        'data_type' => [
                            // The data type must be known to the typed data system.
\Drupal::service('validation.constraint')->createInstance('PluginExists', [
                                'manager' => 'typed_data_manager',
                                // Only primitives are supported because it's not always clear
                                // how to collect, validate, and cast complex structures.
'interface' => PrimitiveInterface::class,
                            ]),
                        ],
                        // The `prompt` and `form` elements, though optional, have their
                        // own sets of constraints,
'prompt' => new Optional([
                            new Collection([
                                'method' => [
                                    new Choice([
                                        'ask',
                                        'askHidden',
                                        'confirm',
                                        'choice',
                                    ]),
                                ],
                                'arguments' => new Optional([
                                    new Type('associative_array'),
                                ]),
                            ]),
                        ]),
                        'form' => new Optional([
                            new Sequentially([
                                new Type('associative_array'),
                                // Every element in the `form` array has to be a form API
                                // property, prefixed with `#`. Because recipe inputs can only
                                // be primitive data types, child elements aren't allowed.
new Callback(function (array $element, ExecutionContextInterface $context) : void {
                                    if (Element::children($element)) {
                                        $context->addViolation('Form elements for recipe inputs cannot have child elements.');
                                    }
                                }),
                            ]),
                        ]),
                        // Every input must define a default value.
'default' => new Required([
                            new Collection([
                                'source' => new Required([
                                    new Choice([
                                        'value',
                                        'config',
                                    ]),
                                ]),
                                'value' => new Optional(),
                                'config' => new Optional([
                                    new Sequentially([
                                        new Type('list'),
                                        new Count(2),
                                        new All([
                                            new Type('string'),
                                            new NotBlank(),
                                        ]),
                                    ]),
                                ]),
                            ]),
                            new Callback(self::validateDefaultValueDefinition(...)),
                        ]),
                    ]),
                ]),
            ]),
            'config' => new Optional([
                new Collection([
                    // Each entry in the `import` list can either be `*` (import all of
                    // the extension's config), or a list of config names to import from
                    // the extension.
                    // @todo https://www.drupal.org/i/3439716 Validate config file name,
                    //   if given.
'import' => new Optional([
                        new All([
                            new AtLeastOneOf([
                                new IdenticalTo('*'),
                                new All([
                                    new Type('string'),
                                    new NotBlank(),
                                    new Regex('/^.+\\./'),
                                ]),
                            ]),
                        ]),
                    ]),
                    'strict' => new Optional([
                        new AtLeastOneOf([
                            new Type('boolean'),
                            new All([
                                new Type('string'),
                                new NotBlank(),
                                new Regex('/^.+\\./'),
                            ]),
                        ], message: 'This value must be a boolean, or a list of config names.', includeInternalMessages: FALSE),
                    ]),
                    'actions' => new Optional([
                        new All([
                            new Type('array'),
                            new NotBlank(),
                            new Callback(callback: self::validateConfigActions(...), payload: $include_path),
                        ]),
                    ]),
                ]),
            ]),
            'content' => new Optional([
                new Type('array'),
            ]),
        ]);
        $recipe_data = Yaml::decode($recipe_contents);
        
        /** @var \Symfony\Component\Validator\ConstraintViolationList $violations */
        $violations = Validation::createValidator()->validate($recipe_data, $constraints);
        if (count($violations) > 0) {
            throw RecipeFileException::fromViolationList($file, $violations);
        }
        $recipe_data += [
            'description' => '',
            'type' => '',
            'recipes' => [],
            'install' => [],
            'config' => [],
            'content' => [],
        ];
        return $recipe_data;
    }
    
    /**
     * Validates the definition of an input's default value.
     *
     * @param array $definition
     *   The array to validate (part of a single input definition).
     * @param \Symfony\Component\Validator\Context\ExecutionContextInterface $context
     *   The validator execution context.
     *
     * @see ::parse()
     */
    public static function validateDefaultValueDefinition(array $definition, ExecutionContextInterface $context) : void {
        $source = $definition['source'];
        if (!array_key_exists($source, $definition)) {
            $context->addViolation("The '{$source}' key is required.");
        }
    }
    
    /**
     * Validates that the value is an available module/theme (installed or not).
     *
     * @param string $value
     *   The value to validate.
     * @param \Symfony\Component\Validator\Context\ExecutionContextInterface $context
     *   The validator execution context.
     *
     * @see \Drupal\Core\Extension\ExtensionList::getAllAvailableInfo()
     */
    private static function validateExtensionIsAvailable(string $value, ExecutionContextInterface $context) : void {
        $name = Dependency::createFromString($value)->getName();
        $all_available = \Drupal::service(ModuleExtensionList::class)->getAllAvailableInfo() + \Drupal::service(ThemeExtensionList::class)->getAllAvailableInfo();
        if (!array_key_exists($name, $all_available)) {
            $context->addViolation('"%extension" is not a known module or theme.', [
                '%extension' => $name,
            ]);
        }
    }
    
    /**
     * Validates that a recipe exists.
     *
     * @param string $name
     *   The machine name of the recipe to look for.
     * @param \Symfony\Component\Validator\Context\ExecutionContextInterface $context
     *   The validator execution context.
     * @param string $include_path
     *   The recipe's include path.
     */
    private static function validateRecipeExists(string $name, ExecutionContextInterface $context, string $include_path) : void {
        if (empty($name)) {
            return;
        }
        try {
            RecipeConfigurator::getIncludedRecipe($include_path, $name);
        } catch (UnknownRecipeException) {
            $context->addViolation('The %name recipe does not exist.', [
                '%name' => $name,
            ]);
        }
    }
    
    /**
     * Validates that the corresponding extension is enabled for a config action.
     *
     * @param mixed $value
     *   The config action; not used.
     * @param \Symfony\Component\Validator\Context\ExecutionContextInterface $context
     *   The validator execution context.
     * @param string $include_path
     *   The recipe's include path.
     */
    private static function validateConfigActions(mixed $value, ExecutionContextInterface $context, string $include_path) : void {
        $config_name = str_replace([
            '[config][actions]',
            '[',
            ']',
        ], '', $context->getPropertyPath());
        [
            $config_provider,
        ] = explode('.', $config_name);
        if ($config_provider === 'core') {
            return;
        }
        $recipe_being_validated = $context->getRoot();
        assert(is_array($recipe_being_validated));
        $configurator = new RecipeConfigurator($recipe_being_validated['recipes'] ?? [], $include_path);
        
        /** @var \Drupal\Core\Extension\ModuleExtensionList $module_list */
        $module_list = \Drupal::service('extension.list.module');
        // The config provider must either be an already-installed module or theme,
        // or an extension being installed by this recipe or a recipe it depends on.
        $all_extensions = [
            array_keys($module_list->getAllInstalledInfo()),
            array_keys(\Drupal::service('extension.list.theme')->getAllInstalledInfo()),
            $recipe_being_validated['install'] ?? [],
            $configurator->listAllExtensions(),
        ];
        // Explicitly treat required modules as installed, even if Drupal isn't
        // installed yet, because we know they WILL be installed.
        foreach ($module_list->getAllAvailableInfo() as $name => $info) {
            if (!empty($info['required'])) {
                $all_extensions[] = $name;
            }
        }
        if (!in_array($config_provider, $all_extensions, TRUE)) {
            $context->addViolation('Config actions cannot be applied to %config_name because the %config_provider extension is not installed, and is not installed by this recipe or any of the recipes it depends on.', [
                '%config_name' => $config_name,
                '%config_provider' => $config_provider,
            ]);
        }
    }

}