<?php

/*
 * This file is part of the symfony package.
 * (c) 2004-2006 Fabien Potencier <fabien.potencier@symfony-project.com>
 * (c) 2004-2006 Sean Kerr <sean@code-box.org>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

/**
 * sfFilterConfigHandler allows you to register filters with the system.
 *
 * @package    symfony
 * @subpackage config
 * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
 * @author     Sean Kerr <sean@code-box.org>
 * @version    SVN: $Id$
 */
class sfFilterConfigHandler extends sfYamlConfigHandler
{
  /**
   * Executes this configuration handler
   *
   * @param array $configFiles An array of absolute filesystem path to a configuration file
   *
   * @return string Data to be written to a cache file
   *
   * @throws sfConfigurationException If a requested configuration file does not exist or is not readable
   * @throws sfParseException If a requested configuration file is improperly formatted
   */
  public function execute($configFiles)
  {
    // parse the yaml
    $config = self::getConfiguration($configFiles);

    // init our data and includes arrays
    $data     = array();
    $includes = array();

    $execution = false;
    $rendering = false;

    // let's do our fancy work
    foreach ($config as $category => $keys)
    {
      if (isset($keys['enabled']) && !$keys['enabled'])
      {
        continue;
      }

      if (!isset($keys['class']))
      {
        // missing class key
        throw new sfParseException(sprintf('Configuration file "%s" specifies category "%s" with missing class key.', $configFiles[0], $category));
      }

      $class = $keys['class'];

      if (isset($keys['file']))
      {
        if (!is_readable($keys['file']))
        {
          // filter file doesn't exist
          throw new sfParseException(sprintf('Configuration file "%s" specifies class "%s" with nonexistent or unreadable file "%s".', $configFiles[0], $class, $keys['file']));
        }

        // append our data
        $includes[] = sprintf("require_once('%s');\n", $keys['file']);
      }

      $condition = true;
      if (isset($keys['param']['condition']))
      {
        $condition = $keys['param']['condition'];
        unset($keys['param']['condition']);
      }

      $type = isset($keys['param']['type']) ? $keys['param']['type'] : null;
      unset($keys['param']['type']);

      if ($condition)
      {
        // parse parameters
        $parameters = isset($keys['param']) ? var_export($keys['param'], true) : 'null';

        // append new data
        if ('security' == $type)
        {
          $data[] = $this->addSecurityFilter($category, $class, $parameters);
        }
        else
        {
          $data[] = $this->addFilter($category, $class, $parameters);
        }

        if ('rendering' == $type)
        {
          $rendering = true;
        }

        if ('execution' == $type)
        {
          $execution = true;
        }
      }
    }

    if (!$rendering)
    {
      throw new sfParseException(sprintf('Configuration file "%s" must register a filter of type "rendering".', $configFiles[0]));
    }

    if (!$execution)
    {
      throw new sfParseException(sprintf('Configuration file "%s" must register a filter of type "execution".', $configFiles[0]));
    }

    // compile data
    $retval = sprintf("<?php\n".
                      "// auto-generated by sfFilterConfigHandler\n".
                      "// date: %s\n%s\n%s\n\n", date('Y/m/d H:i:s'),
                      implode("\n", $includes), implode("\n", $data));

    return $retval;
  }

  /**
   * Adds a filter statement to the data.
   *
   * @param string $category   The category name
   * @param string $class      The filter class name
   * @param array  $parameters Filter default parameters
   *
   * @return string The PHP statement
   */
  protected function addFilter($category, $class, $parameters)
  {
    return sprintf("\nlist(\$class, \$parameters) = (array) sfConfig::get('sf_%s_filter', array('%s', %s));\n".
                      "\$filter = new \$class(sfContext::getInstance(), \$parameters);\n".
                      "\$this->register(\$filter);",
                      $category, $class, $parameters);
  }

  /**
   * Adds a security filter statement to the data.
   *
   * @param string $category   The category name
   * @param string $class      The filter class name
   * @param array  $parameters Filter default parameters
   *
   * @return string The PHP statement
   */
  protected function addSecurityFilter($category, $class, $parameters)
  {
    return <<<EOF

// does this action require security?
if (\$actionInstance->isSecure())
{
  {$this->addFilter($category, $class, $parameters)}
}
EOF;
  }

  /**
   * @see sfConfigHandler
   */
  static public function getConfiguration(array $configFiles)
  {
    $config = self::parseYaml($configFiles[0]);
    foreach (array_slice($configFiles, 1) as $i => $configFile)
    {
      // we get the order of the new file and merge with the previous configurations
      $previous = $config;

      $config = array();
      foreach (self::parseYaml($configFile) as $key => $value)
      {
        $value = (array) $value;
        $config[$key] = isset($previous[$key]) ? sfToolkit::arrayDeepMerge($previous[$key], $value) : $value;
      }

      // check that every key in previous array is still present (to avoid problem when upgrading)
      foreach (array_keys($previous) as $key)
      {
        if (!isset($config[$key]))
        {
          throw new sfConfigurationException(sprintf('The filter name "%s" is defined in "%s" but not present in "%s" file. To disable a filter, add a "enabled" key with a false value.', $key, $configFiles[$i], $configFile));
        }
      }
    }

    $config = self::replaceConstants($config);

    foreach ($config as $category => $keys)
    {
      if (isset($keys['file']))
      {
        $config[$category]['file'] = self::replacePath($keys['file']);
      }
    }

    return $config;
  }
}