<?php

/*

 * This file is part of SwiftMailer.

 * (c) 2004-2009 Chris Corbyn

 *

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

 * file that was distributed with this source code.

 */

/**

 * An abstract base MIME Header.

 * @package Swift

 * @subpackage Mime

 * @author Chris Corbyn

 */

class Swift_Mime_Headers_ParameterizedHeader

  extends Swift_Mime_Headers_UnstructuredHeader

  implements Swift_Mime_ParameterizedHeader

{

  /**

   * The Encoder used to encode the parameters.

   * @var Swift_Encoder

   * @access private

   */

  private $_paramEncoder;

  /**

   * The parameters as an associative array.

   * @var string[]

   * @access private

   */

  private $_params = array();

  /**

   * RFC 2231's definition of a token.

   * @var string

   * @access private

   */

  private $_tokenRe;

  /**

   * Creates a new ParameterizedHeader with $name.

   * @param string $name

   * @param Swift_Mime_HeaderEncoder $encoder

   * @param Swift_Encoder $paramEncoder, optional

   * @param Swift_Mime_Grammar $grammar

   */ 

  public function __construct($name, Swift_Mime_HeaderEncoder $encoder,

    Swift_Encoder $paramEncoder = null, Swift_Mime_Grammar $grammar)

  {

    parent::__construct($name, $encoder, $grammar);

    $this->_paramEncoder = $paramEncoder;

    $this->_tokenRe = '(?:[\x21\x23-\x27\x2A\x2B\x2D\x2E\x30-\x39\x41-\x5A\x5E-\x7E]+)';

  }

  /**

   * Get the type of Header that this instance represents.

   * @return int

   * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX

   * @see TYPE_DATE, TYPE_ID, TYPE_PATH

   */

  public function getFieldType()

  {

    return self::TYPE_PARAMETERIZED;

  }

  /**

   * Set the character set used in this Header.

   * @param string $charset

   */

  public function setCharset($charset)

  {

    parent::setCharset($charset);

    if (isset($this->_paramEncoder))

    {

      $this->_paramEncoder->charsetChanged($charset);

    }

  }

  /**

   * Set the value of $parameter.

   * @param string $parameter

   * @param string $value

   */

  public function setParameter($parameter, $value)

  {

    $this->setParameters(array_merge($this->getParameters(), array($parameter => $value)));

  }

  /**

   * Get the value of $parameter.

   * @return string

   */

  public function getParameter($parameter)

  {

    $params = $this->getParameters();

    return array_key_exists($parameter, $params)

      ? $params[$parameter]

      : null;

  }

  /**

   * Set an associative array of parameter names mapped to values.

   * @param string[]

   */

  public function setParameters(array $parameters)

  {

    $this->clearCachedValueIf($this->_params != $parameters);

    $this->_params = $parameters;

  }

  /**

   * Returns an associative array of parameter names mapped to values.

   * @return string[]

   */

  public function getParameters()

  {

    return $this->_params;

  }

  /**

   * Get the value of this header prepared for rendering.

   * @return string

   */

  public function getFieldBody() //TODO: Check caching here

  {

    $body = parent::getFieldBody();

    foreach ($this->_params as $name => $value)

    {

      if (!is_null($value))

      {

        //Add the parameter

        $body .= '; ' . $this->_createParameter($name, $value);

      }

    }

    return $body;

  }

  // -- Protected methods

  /**

   * Generate a list of all tokens in the final header.

   * This doesn't need to be overridden in theory, but it is for implementation

   * reasons to prevent potential breakage of attributes.

   * @return string[]

   * @access protected

   */

  protected function toTokens($string = null)

  {

    $tokens = parent::toTokens(parent::getFieldBody());

    //Try creating any parameters

    foreach ($this->_params as $name => $value)

    {

      if (!is_null($value))

      {

        //Add the semi-colon separator

        $tokens[count($tokens)-1] .= ';';

        $tokens = array_merge($tokens, $this->generateTokenLines(

          ' ' . $this->_createParameter($name, $value)

          ));

      }

    }

    return $tokens;

  }

  // -- Private methods

  /**

   * Render a RFC 2047 compliant header parameter from the $name and $value.

   * @param string $name

   * @param string $value

   * @return string

   * @access private

   */

  private function _createParameter($name, $value)

  {

    $origValue = $value;

    $encoded = false;

    //Allow room for parameter name, indices, "=" and DQUOTEs

    $maxValueLength = $this->getMaxLineLength() - strlen($name . '=*N"";') - 1;

    $firstLineOffset = 0;

    //If it's not already a valid parameter value...

    if (!preg_match('/^' . $this->_tokenRe . '$/D', $value))

    {

      //TODO: text, or something else??

      //... and it's not ascii

      if (!preg_match('/^' . $this->getGrammar()->getDefinition('text') . '*$/D', $value))

      {

        $encoded = true;

        //Allow space for the indices, charset and language

        $maxValueLength = $this->getMaxLineLength() - strlen($name . '*N*="";') - 1;

        $firstLineOffset = strlen(

          $this->getCharset() . "'" . $this->getLanguage() . "'"

          );

      }

    }

    //Encode if we need to

    if ($encoded || strlen($value) > $maxValueLength)

    {

      if (isset($this->_paramEncoder))

      {

        $value = $this->_paramEncoder->encodeString(

          $origValue, $firstLineOffset, $maxValueLength

          );

      }

      else //We have to go against RFC 2183/2231 in some areas for interoperability

      {

        $value = $this->getTokenAsEncodedWord($origValue);

        $encoded = false;

      }

    }

    $valueLines = isset($this->_paramEncoder) ? explode("\r\n", $value) : array($value);

    //Need to add indices

    if (count($valueLines) > 1)

    {

      $paramLines = array();

      foreach ($valueLines as $i => $line)

      {

        $paramLines[] = $name . '*' . $i .

          $this->_getEndOfParameterValue($line, $encoded, $i == 0);

      }

      return implode(";\r\n ", $paramLines);

    }

    else

    {

      return $name . $this->_getEndOfParameterValue(

        $valueLines[0], $encoded, true

        );

    }

  }

  /**

   * Returns the parameter value from the "=" and beyond.

   * @param string $value to append

   * @param boolean $encoded

   * @param boolean $firstLine

   * @return string

   * @access private

   */

  private function _getEndOfParameterValue($value, $encoded = false, $firstLine = false)

  {

    if (!preg_match('/^' . $this->_tokenRe . '$/D', $value))

    {

      $value = '"' . $value . '"';

    }

    $prepend = '=';

    if ($encoded)

    {

      $prepend = '*=';

      if ($firstLine)

      {

        $prepend = '*=' . $this->getCharset() . "'" . $this->getLanguage() .

          "'";

      }

    }

    return $prepend . $value;

  }

}