<?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\HttpKernel\Controller;

use Symfony\Component\HttpKernel\Log\LoggerInterface;

use Symfony\Component\HttpFoundation\Request;

/**

 * ControllerResolver.

 *

 * This implementation uses the '_controller' request attribute to determine

 * the controller to execute and uses the request attributes to determine

 * the controller method arguments.

 *

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

 *

 * @api

 */

class ControllerResolver implements ControllerResolverInterface

{

    private $logger;

    /**

     * Constructor.

     *

     * @param LoggerInterface $logger A LoggerInterface instance

     */

    public function __construct(LoggerInterface $logger = null)

    {

        $this->logger = $logger;

    }

    /**

     * Returns the Controller instance associated with a Request.

     *

     * This method looks for a '_controller' request attribute that represents

     * the controller name (a string like ClassName::MethodName).

     *

     * @param Request $request A Request instance

     *

     * @return mixed|Boolean A PHP callable representing the Controller,

     *                       or false if this resolver is not able to determine the controller

     *

     * @throws \InvalidArgumentException|\LogicException If the controller can't be found

     *

     * @api

     */

    public function getController(Request $request)

    {

        if (!$controller = $request->attributes->get('_controller')) {

            if (null !== $this->logger) {

                $this->logger->warn('Unable to look for the controller as the "_controller" parameter is missing');

            }

            return false;

        }

        if (is_array($controller) || (is_object($controller) && method_exists($controller, '__invoke'))) {

            return $controller;

        }

        if (false === strpos($controller, ':') && method_exists($controller, '__invoke')) {

            return new $controller;

        }

        list($controller, $method) = $this->createController($controller);

        if (!method_exists($controller, $method)) {

            throw new \InvalidArgumentException(sprintf('Method "%s::%s" does not exist.', get_class($controller), $method));

        }

        return array($controller, $method);

    }

    /**

     * Returns the arguments to pass to the controller.

     *

     * @param Request $request    A Request instance

     * @param mixed   $controller A PHP callable

     *

     * @throws \RuntimeException When value for argument given is not provided

     *

     * @api

     */

    public function getArguments(Request $request, $controller)

    {

        if (is_array($controller)) {

            $r = new \ReflectionMethod($controller[0], $controller[1]);

        } elseif (is_object($controller)) {

            $r = new \ReflectionObject($controller);

            $r = $r->getMethod('__invoke');

        } else {

            $r = new \ReflectionFunction($controller);

        }

        return $this->doGetArguments($request, $controller, $r->getParameters());

    }

    protected function doGetArguments(Request $request, $controller, array $parameters)

    {

        $attributes = $request->attributes->all();

        $arguments = array();

        foreach ($parameters as $param) {

            if (array_key_exists($param->getName(), $attributes)) {

                $arguments[] = $attributes[$param->getName()];

            } elseif ($param->getClass() && $param->getClass()->isInstance($request)) {

                $arguments[] = $request;

            } elseif ($param->isDefaultValueAvailable()) {

                $arguments[] = $param->getDefaultValue();

            } else {

                if (is_array($controller)) {

                    $repr = sprintf('%s::%s()', get_class($controller[0]), $controller[1]);

                } elseif (is_object($controller)) {

                    $repr = get_class($controller);

                } else {

                    $repr = $controller;

                }

                throw new \RuntimeException(sprintf('Controller "%s" requires that you provide a value for the "$%s" argument (because there is no default value or because there is a non optional argument after this one).', $repr, $param->getName()));

            }

        }

        return $arguments;

    }

    /**

     * Returns a callable for the given controller.

     *

     * @param string $controller A Controller string

     *

     * @return mixed A PHP callable

     */

    protected function createController($controller)

    {

        if (false === strpos($controller, '::')) {

            throw new \InvalidArgumentException(sprintf('Unable to find controller "%s".', $controller));

        }

        list($class, $method) = explode('::', $controller);

        if (!class_exists($class)) {

            throw new \InvalidArgumentException(sprintf('Class "%s" does not exist.', $class));

        }

        return array(new $class(), $method);

    }

}