<?php

/*

 * This file is part of the Symfony package.

 *

 * (c) Fabien Potencier <fabien@symfony.com>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

namespace Symfony\Component\Routing\Loader;

use Symfony\Component\Routing\RouteCollection;

use Symfony\Component\Routing\Route;

use Symfony\Component\Config\Resource\FileResource;

use Symfony\Component\Yaml\Yaml;

use Symfony\Component\Config\Loader\FileLoader;

/**

 * YamlFileLoader loads Yaml routing files.

 *

 * @author Fabien Potencier <fabien@symfony.com>

 *

 * @api

 */

class YamlFileLoader extends FileLoader

{

    private static $availableKeys = array(

        'type', 'resource', 'prefix', 'pattern', 'options', 'defaults', 'requirements'

    );

    /**

     * Loads a Yaml file.

     *

     * @param string $file A Yaml file path

     * @param string $type The resource type

     *

     * @return RouteCollection A RouteCollection instance

     *

     * @throws \InvalidArgumentException When route can't be parsed

     *

     * @api

     */

    public function load($file, $type = null)

    {

        $path = $this->locator->locate($file);

        $config = Yaml::parse($path);

        $collection = new RouteCollection();

        $collection->addResource(new FileResource($path));

        // empty file

        if (null === $config) {

            $config = array();

        }

        // not an array

        if (!is_array($config)) {

            throw new \InvalidArgumentException(sprintf('The file "%s" must contain a YAML array.', $file));

        }

        foreach ($config as $name => $config) {

            $config = $this->normalizeRouteConfig($config);

            if (isset($config['resource'])) {

                $type = isset($config['type']) ? $config['type'] : null;

                $prefix = isset($config['prefix']) ? $config['prefix'] : null;

                $this->setCurrentDir(dirname($path));

                $collection->addCollection($this->import($config['resource'], $type, false, $file), $prefix);

            } else {

                $this->parseRoute($collection, $name, $config, $path);

            }

        }

        return $collection;

    }

    /**

     * Returns true if this class supports the given resource.

     *

     * @param mixed  $resource A resource

     * @param string $type     The resource type

     *

     * @return Boolean True if this class supports the given resource, false otherwise

     *

     * @api

     */

    public function supports($resource, $type = null)

    {

        return is_string($resource) && 'yml' === pathinfo($resource, PATHINFO_EXTENSION) && (!$type || 'yaml' === $type);

    }

    /**

     * Parses a route and adds it to the RouteCollection.

     *

     * @param RouteCollection $collection A RouteCollection instance

     * @param string          $name       Route name

     * @param array           $config     Route definition

     * @param string          $file       A Yaml file path

     *

     * @throws \InvalidArgumentException When config pattern is not defined for the given route

     */

    protected function parseRoute(RouteCollection $collection, $name, $config, $file)

    {

        $defaults = isset($config['defaults']) ? $config['defaults'] : array();

        $requirements = isset($config['requirements']) ? $config['requirements'] : array();

        $options = isset($config['options']) ? $config['options'] : array();

        if (!isset($config['pattern'])) {

            throw new \InvalidArgumentException(sprintf('You must define a "pattern" for the "%s" route.', $name));

        }

        $route = new Route($config['pattern'], $defaults, $requirements, $options);

        $collection->add($name, $route);

    }

    /**

     * Normalize route configuration.

     *

     * @param array  $config A resource config

     *

     * @return array

     *

     * @throws InvalidArgumentException if one of the provided config keys is not supported

     */

    private function normalizeRouteConfig(array $config)

    {

        foreach ($config as $key => $value) {

            if (!in_array($key, self::$availableKeys)) {

                throw new \InvalidArgumentException(sprintf(

                    'Yaml routing loader does not support given key: "%s". Expected one of the (%s).',

                    $key, implode(', ', self::$availableKeys)

                ));

            }

        }

        return $config;

    }

}