<?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.
 */

require_once dirname(__FILE__) . '/../HeaderEncoder.php';
require_once dirname(__FILE__) . '/../../Encoder/QpEncoder.php';
require_once dirname(__FILE__) . '/../../CharacterStream.php';

/**
 * Handles Quoted Printable (Q) Header Encoding in Swift Mailer.
 * @package Swift
 * @subpackage Mime
 * @author Chris Corbyn
 */
class Swift_Mime_HeaderEncoder_QpHeaderEncoder extends Swift_Encoder_QpEncoder
  implements Swift_Mime_HeaderEncoder
{

  /**
   * Creates a new QpHeaderEncoder for the given CharacterStream.
   * @param Swift_CharacterStream $charStream to use for reading characters
   */
  public function __construct(Swift_CharacterStream $charStream)
  {
    parent::__construct($charStream);
  }
  
  protected function initSafeMap()
  {
    foreach (array_merge(
      range(0x61, 0x7A), range(0x41, 0x5A),
      range(0x30, 0x39), array(0x20, 0x21, 0x2A, 0x2B, 0x2D, 0x2F)
      ) as $byte)
    {
      $this->_safeMap[$byte] = chr($byte);
    }
  }

  /**
   * Get the name of this encoding scheme.
   * Returns the string 'Q'.
   * @return string
   */
  public function getName()
  {
    return 'Q';
  }

  /**
   * Takes an unencoded string and produces a Q encoded string from it.
   * @param string $string to encode
   * @param int $firstLineOffset, optional
   * @param int $maxLineLength, optional, 0 indicates the default of 76 chars
   * @return string
   */
  public function encodeString($string, $firstLineOffset = 0,
    $maxLineLength = 0)
  {
    return str_replace(array(' ', '=20', "=\r\n"), array('_', '_', "\r\n"),
      parent::encodeString($string, $firstLineOffset, $maxLineLength)
      );
  }

}
