class NavigationRenderer

final class NavigationRenderer {
    
    /**
     * Use the default Drupal logo in the navigation.
     */
    const LOGO_PROVIDER_DEFAULT = 'default';
    
    /**
     * Hide the logo in the navigation.
     */
    const LOGO_PROVIDER_HIDE = 'hide';
    
    /**
     * Use the custom provided logo in the navigation.
     */
    const LOGO_PROVIDER_CUSTOM = 'custom';
    
    /**
     * A list of all the link paths of enabled content entities.
     *
     * @var array
     */
    protected array $contentEntityPaths;
    
    /**
     * The navigation local tasks render array.
     *
     * @var array
     */
    protected array $localTasks;
    
    /**
     * Construct a new NavigationRenderer object.
     */
    public function __construct(ConfigFactoryInterface $configFactory, ModuleHandlerInterface $moduleHandler, RouteMatchInterface $routeMatch, LocalTaskManagerInterface $localTaskManager, EntityTypeManagerInterface $entityTypeManager, ImageFactory $imageFactory, FileUrlGeneratorInterface $fileUrlGenerator, SectionStorageManagerInterface $sectionStorageManager, RequestStack $requestStack, ModuleExtensionList $moduleExtensionList) {
    }
    
    /**
     * Remove the toolbar provided by Toolbar module.
     *
     * @param array $page_top
     *   A renderable array representing the top of the page.
     *
     * @see toolbar_page_top()
     * @see hook_page_top()
     */
    public function removeToolbar(array &$page_top) : void {
        if (isset($page_top['toolbar'])) {
            unset($page_top['toolbar']);
        }
    }
    
    /**
     * Build out the navigation bar.
     *
     * @param array $page_top
     *   A renderable array representing the top of the page.
     *
     * @see toolbar_page_top()
     * @see hook_page_top()
     */
    public function buildNavigation(array &$page_top) : void {
        $logo_settings = $this->configFactory
            ->get('navigation.settings');
        $logo_provider = $logo_settings->get('logo.provider');
        $cacheability = new CacheableMetadata();
        $contexts = [
            'navigation' => new Context(ContextDefinition::create('string'), 'navigation'),
        ];
        $storage = $this->sectionStorageManager
            ->findByContext($contexts, $cacheability);
        $build = [];
        if ($storage) {
            foreach ($storage->getSections() as $delta => $section) {
                $build[$delta] = $section->toRenderArray([]);
            }
        }
        // The render array is built based on decisions made by SectionStorage
        // plugins and therefore it needs to depend on the accumulated
        // cacheability of those decisions.
        $cacheability->addCacheableDependency($logo_settings)
            ->addCacheableDependency($this->configFactory
            ->get('navigation.block_layout'));
        $cacheability->applyTo($build);
        $module_path = $this->requestStack
            ->getCurrentRequest()
            ->getBasePath() . '/' . $this->moduleExtensionList
            ->getPath('navigation');
        $asset_url = $module_path . '/assets/fonts/inter-var.woff2';
        $defaults = [
            'settings' => [
                'hide_logo' => $logo_provider === self::LOGO_PROVIDER_HIDE,
            ],
            '#attached' => [
                'html_head_link' => [
                    [
                        [
                            'rel' => 'preload',
                            'href' => $asset_url,
                            'as' => 'font',
                            'crossorigin' => 'anonymous',
                        ],
                    ],
                ],
            ],
        ];
        $build[0] = NestedArray::mergeDeepArray([
            $build[0],
            $defaults,
        ]);
        $page_top['navigation'] = $build;
        if ($logo_provider === self::LOGO_PROVIDER_CUSTOM) {
            $logo_path = $logo_settings->get('logo.path');
            if (!empty($logo_path) && is_file($logo_path)) {
                $logo_managed_url = $this->fileUrlGenerator
                    ->generateAbsoluteString($logo_path);
                $image = $this->imageFactory
                    ->get($logo_path);
                $page_top['navigation'][0]['settings']['logo_path'] = $logo_managed_url;
                if ($image->isValid()) {
                    $page_top['navigation'][0]['settings']['logo_width'] = $image->getWidth();
                    $page_top['navigation'][0]['settings']['logo_height'] = $image->getHeight();
                }
            }
        }
    }
    
    /**
     * Build the top bar for content entity pages.
     *
     * @param array $page_top
     *   A renderable array representing the top of the page.
     *
     * @see navigation_page_top()
     * @see hook_page_top()
     */
    public function buildTopBar(array &$page_top) : void {
        if (!$this->moduleHandler
            ->moduleExists('navigation_top_bar')) {
            return;
        }
        $page_top['top_bar'] = [
            '#theme' => 'top_bar',
            '#attached' => [
                'library' => [
                    'navigation/internal.navigation',
                ],
            ],
            '#cache' => [
                'contexts' => [
                    'url.path',
                    'user.permissions',
                ],
            ],
        ];
        // Local tasks for content entities.
        if ($this->hasLocalTasks()) {
            $local_tasks = $this->getLocalTasks();
            $page_top['top_bar']['#local_tasks'] = [
                '#theme' => 'top_bar_local_tasks',
                '#local_tasks' => $local_tasks['tasks'],
            ];
            assert($local_tasks['cacheability'] instanceof CacheableMetadata);
            CacheableMetadata::createFromRenderArray($page_top['top_bar'])->addCacheableDependency($local_tasks['cacheability'])
                ->applyTo($page_top['top_bar']);
        }
    }
    
    /**
     * Alter the build of any local_tasks_block plugin block.
     *
     * If we are showing the local tasks in the top bar, hide the local tasks
     * from display to avoid duplicating the links.
     *
     * @param array $build
     *   A renderable array representing the local_tasks_block plugin block to be
     *   rendered.
     * @param \Drupal\Core\Block\BlockPluginInterface $block
     *   Block plugin object representing a local_tasks_block.
     *
     * @see navigation_block_build_local_tasks_block_alter()
     */
    public function removeLocalTasks(array &$build, BlockPluginInterface $block) : void {
        if ($block->getPluginId() !== 'local_tasks_block') {
            return;
        }
        if ($this->hasLocalTasks() && $this->moduleHandler
            ->moduleExists('navigation_top_bar')) {
            $build['#access'] = FALSE;
        }
    }
    
    /**
     * Local tasks list based on user access.
     *
     * @return array
     *   Local tasks keyed by route name.
     */
    private function getLocalTasks() : array {
        if (isset($this->localTasks)) {
            return $this->localTasks;
        }
        $cacheability = new CacheableMetadata();
        $cacheability->addCacheableDependency($this->localTaskManager);
        $this->localTasks = [
            'tasks' => [],
            'cacheability' => $cacheability,
        ];
        // For now, we're only interested in local tasks corresponding to a content
        // entity.
        if (!$this->meetsContentEntityRoutesCondition()) {
            return $this->localTasks;
        }
        $entity_local_tasks = $this->localTaskManager
            ->getLocalTasks($this->routeMatch
            ->getRouteName());
        foreach ($entity_local_tasks['tabs'] as $route_name => $local_task) {
            // The $local_task array that we get here is tailor-made for use
            // with the menu-local-tasks.html.twig, eg. the menu_local_task
            // theme hook. It has all the information we need, but we're not
            // rendering local tasks, or tabs, we're rendering a simple list of
            // links. Here we're taking advantage of all the good stuff found in
            // the render array, namely the #link, and #access properties, using
            // them to render a simple link.
            // @see \Drupal\Core\Menu\LocalTaskManager::getTasksBuild()
            $link = $local_task['#link'];
            $link['localized_options'] += [
                'set_active_class' => TRUE,
            ];
            $this->localTasks['tasks'][$route_name] = [
                '#theme' => 'top_bar_local_task',
                '#link' => [
                    '#type' => 'link',
                    '#title' => $link['title'],
                    '#url' => $link['url'],
                    '#options' => $link['localized_options'],
                ],
                '#access' => $local_task['#access'],
            ];
        }
        $this->localTasks['cacheability'] = $cacheability->merge($entity_local_tasks['cacheability']);
        return $this->localTasks;
    }
    
    /**
     * Do we have local tasks that we want to show in the top bar?
     *
     * @return bool
     *   TRUE if there are local tasks available for the top bar, FALSE otherwise.
     */
    private function hasLocalTasks() : bool {
        $local_tasks = $this->getLocalTasks();
        return !empty($local_tasks['tasks']);
    }
    
    /**
     * Determines if content entity route condition is met.
     *
     * @return bool
     *   TRUE if the content entity route condition is met, FALSE otherwise.
     */
    protected function meetsContentEntityRoutesCondition() : bool {
        return array_key_exists($this->routeMatch
            ->getRouteObject()
            ->getPath(), $this->getContentEntityPaths());
    }
    
    /**
     * Returns the paths for the link templates of all content entities.
     *
     * @return array
     *   An array of all content entity type IDs, keyed by the corresponding link
     *   template paths.
     */
    protected function getContentEntityPaths() : array {
        if (isset($this->contentEntityPaths)) {
            return $this->contentEntityPaths;
        }
        $this->contentEntityPaths = [];
        $entity_types = $this->entityTypeManager
            ->getDefinitions();
        foreach ($entity_types as $entity_type) {
            if ($entity_type->entityClassImplements(ContentEntityInterface::class)) {
                $entity_paths = $this->getContentEntityTypePaths($entity_type);
                $this->contentEntityPaths = array_merge($this->contentEntityPaths, $entity_paths);
            }
        }
        return $this->contentEntityPaths;
    }
    
    /**
     * Returns the path for the link template for a given content entity type.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
     *   The entity type definition.
     *
     * @return array
     *   Array containing the paths for the given content entity type.
     */
    protected function getContentEntityTypePaths(EntityTypeInterface $entity_type) : array {
        $paths = array_filter($entity_type->getLinkTemplates(), fn($template) => $template !== 'collection', ARRAY_FILTER_USE_KEY);
        if ($this->isLayoutBuilderEntityType($entity_type)) {
            $paths[] = $entity_type->getLinkTemplate('canonical') . '/layout';
        }
        return array_fill_keys($paths, $entity_type->id());
    }
    
    /**
     * Determines if a given entity type is layout builder relevant or not.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
     *   The entity type.
     *
     * @return bool
     *   Whether this entity type is a Layout builder candidate or not
     *
     * @see \Drupal\layout_builder\Plugin\SectionStorage\OverridesSectionStorage::getEntityTypes()
     */
    protected function isLayoutBuilderEntityType(EntityTypeInterface $entity_type) : bool {
        return $entity_type->entityClassImplements(FieldableEntityInterface::class) && $entity_type->hasHandlerClass('form', 'layout_builder') && $entity_type->hasViewBuilderClass() && $entity_type->hasLinkTemplate('canonical');
    }

}