<?php

/*

 * This file is part of the Symfony framework.

 *

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

 *

 * This source file is subject to the MIT license that is bundled

 * with this source code in the file LICENSE.

 */

namespace Symfony\Bundle\AsseticBundle\Twig;

use Assetic\Extension\Twig\AsseticFilterFunction;

/**

 * Assetic node visitor.

 *

 * @author Kris Wallsmith <kris@symfony.com>

 */

class AsseticNodeVisitor implements \Twig_NodeVisitorInterface

{

    public function enterNode(\Twig_NodeInterface $node, \Twig_Environment $env)

    {

        return $node;

    }

    public function leaveNode(\Twig_NodeInterface $node, \Twig_Environment $env)

    {

        if (!$formula = $this->checkNode($node, $env)) {

            return $node;

        }

        list($input, $filters, $options) = $formula;

        $line = $node->getLine();

        // check context and call either asset() or path()

        return new \Twig_Node_Expression_Conditional(

            new \Twig_Node_Expression_GetAttr(

                new \Twig_Node_Expression_Name('assetic', $line),

                new \Twig_Node_Expression_Constant('use_controller', $line),

                new \Twig_Node(),

                \Twig_TemplateInterface::ARRAY_CALL,

                $line

            ),

            new \Twig_Node_Expression_Function(

                new \Twig_Node_Expression_Name('path', $line),

                new \Twig_Node(array(

                    new \Twig_Node_Expression_Constant('_assetic_'.$options['name'], $line),

                )),

                $line

            ),

            new \Twig_Node_Expression_Function(

                new \Twig_Node_Expression_Name('asset', $line),

                new \Twig_Node(array($node, new \Twig_Node_Expression_Constant(isset($options['package']) ? $options['package'] : null, $line))),

                $line

            ),

            $line

        );

    }

    /**

     * Extracts formulae from filter function nodes.

     *

     * @return array|null The formula

     */

    private function checkNode(\Twig_NodeInterface $node, \Twig_Environment $env)

    {

        if ($node instanceof \Twig_Node_Expression_Function) {

            $name = $node->getNode('name')->getAttribute('name');

            if ($env->getFunction($name) instanceof AsseticFilterFunction) {

                $arguments = array();

                foreach ($node->getNode('arguments') as $argument) {

                    $arguments[] = eval('return '.$env->compile($argument).';');

                }

                $invoker = $env->getExtension('assetic')->getFilterInvoker($name);

                $factory = $invoker->getFactory();

                $inputs = isset($arguments[0]) ? (array) $arguments[0] : array();

                $filters = $invoker->getFilters();

                $options = array_replace($invoker->getOptions(), isset($arguments[1]) ? $arguments[1] : array());

                if (!isset($options['name'])) {

                    $options['name'] = $factory->generateAssetName($inputs, $filters);

                }

                return array($inputs, $filters, $options);

            }

        }

    }

    public function getPriority()

    {

        return 0;

    }

}