<?php

/*
 * This file is part of Twig.
 *
 * (c) 2010 Fabien Potencier
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

/**
 * Marks a section of a template as untrusted code that must be evaluated in the sandbox mode.
 *
 * <pre>
 * {% sandbox %}
 *     {% include 'user.html' %}
 * {% endsandbox %}
 * </pre>
 *
 * @see http://www.twig-project.org/doc/api.html#sandbox-extension for details
 */
class Twig_TokenParser_Sandbox extends Twig_TokenParser
{
  /**
   * Parses a token and returns a node.
   *
   * @param Twig_Token $token A Twig_Token instance
   *
   * @return Twig_NodeInterface A Twig_NodeInterface instance
   */
  public function parse(Twig_Token $token)
  {
    $this->parser->getStream()->expect(Twig_Token::BLOCK_END_TYPE);
    $body = $this->parser->subparse([$this, 'decideBlockEnd'], true);
    $this->parser->getStream()->expect(Twig_Token::BLOCK_END_TYPE);

    // in a sandbox tag, only include tags are allowed
    if (!$body instanceof Twig_Node_Include) {
      foreach ($body as $node) {
        if ($node instanceof Twig_Node_Text && ctype_space($node->getAttribute('data'))) {
          continue;
        }

        if (!$node instanceof Twig_Node_Include) {
          throw new Twig_Error_Syntax('Only "include" tags are allowed within a "sandbox" section', $node->getLine(), $this->parser->getFilename());
        }
      }
    }

    return new Twig_Node_Sandbox($body, $token->getLine(), $this->getTag());
  }

  public function decideBlockEnd(Twig_Token $token)
  {
    return $token->test('endsandbox');
  }

  /**
   * Gets the tag name associated with this token parser.
   *
   * @return string The tag name
   */
  public function getTag()
  {
    return 'sandbox';
  }
}
