<?php

/**
 * @file
 * Contains \Drupal\Core\Routing\NestedRouteProvider.
 */

namespace Drupal\Core\Routing;

use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\Routing\Exception\RouteNotFoundException;
use Symfony\Component\Routing\RouteCollection;
use Symfony\Component\Validator\Constraints\Collection;

/**
 * Implements a route provider which takes multiple route providers into
 * account.
 */
class NestedRouteProvider implements RouteProviderInterface {

  /**
   * The route providers.
   *
   * @var array|\Drupal\Core\Routing\RouteProviderInterface[]
   */
  protected $routeProviders = [];

  /**
   * @param \Drupal\Core\Routing\RouteProviderInterface[] $route_providers
   *   The route providers.
   */
  public function __construct(array $route_providers) {
    $this->routeProviders = $route_providers;
  }

  /**
   * {@inheritdoc}
   */
  public function getRoutesByPattern($pattern) {
    $collection = new RouteCollection();
    foreach ($this->routeProviders as $provider) {
      $collection->addCollection($provider->getRoutesByPattern($pattern));
    }
    return $collection;
  }

  /**
   * {@inheritdoc}
   */
  public function getAllRoutes() {
    $collection = new RouteCollection();
    foreach ($this->routeProviders as $provider) {
      $collection->addCollection(new RouteCollection($provider->getAllRoutes()));
    }
    return $collection;
  }

  /**
   * {@inheritdoc}
   */
  public function reset() {
    foreach ($this->routeProviders as $provider) {
      $provider->reset();
    }
  }

  /**
   * {@inheritdoc}
   */
  public function getRouteCollectionForRequest(Request $request) {
    $collection = new RouteCollection();
    foreach ($this->routeProviders as $provider) {
      $collection->addCollection($provider->getRouteCollectionForRequest($request));
    }
    return $collection;
  }

  /**
   * {@inheritdoc}
   */
  public function getRouteByName($name) {
    foreach ($this->routeProviders as $provider) {
      try {
        $route = $provider->getRouteByName($name);
        return $route;
      }
      catch (RouteNotFoundException $e) {
        continue;
      }
    }
    throw new RouteNotFoundException();
  }

  /**
   * {@inheritdoc}
   */
  public function getRoutesByNames($names) {
    $routes = [];
    foreach ($this->routeProviders as $provider) {
      $routes += $provider->getRoutesByNames($names);
      $names = array_diff($names, array_keys($routes));
    }
    return $routes;
  }

}