<?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.

 */

/**

 * A collection of MIME headers.

 * 

 * @package Swift

 * @subpackage Mime

 * 

 * @author Chris Corbyn

 */

class Swift_Mime_SimpleHeaderSet implements Swift_Mime_HeaderSet

{

  /** HeaderFactory */

  private $_factory;

  /** Collection of set Headers */

  private $_headers = array();

  /** Field ordering details */

  private $_order = array();

  /** List of fields which are required to be displayed */

  private $_required = array();

  /** The charset used by Headers */

  private $_charset;

  /**

   * Create a new SimpleHeaderSet with the given $factory.

   * 

   * @param Swift_Mime_HeaderFactory $factory

   * @param string $charset

   */

  public function __construct(Swift_Mime_HeaderFactory $factory,

    $charset = null)

  {

    $this->_factory = $factory;

    if (isset($charset))

    {

      $this->setCharset($charset);

    }

  }

  /**

   * Set the charset used by these headers.

   * 

   * @param string $charset

   */

  public function setCharset($charset)

  {

    $this->_charset = $charset;

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

    $this->_notifyHeadersOfCharset($charset);

  }

  /**

   * Add a new Mailbox Header with a list of $addresses.

   * 

   * @param string $name

   * @param array|string $addresses

   */

  public function addMailboxHeader($name, $addresses = null)

  {

    $this->_storeHeader($name,

      $this->_factory->createMailboxHeader($name, $addresses));

  }

  /**

   * Add a new Date header using $timestamp (UNIX time).

   * 

   * @param string $name

   * @param int $timestamp

   */

  public function addDateHeader($name, $timestamp = null)

  {

    $this->_storeHeader($name,

      $this->_factory->createDateHeader($name, $timestamp));

  }

  /**

   * Add a new basic text header with $name and $value.

   * 

   * @param string $name

   * @param string $value

   */

  public function addTextHeader($name, $value = null)

  {

    $this->_storeHeader($name,

      $this->_factory->createTextHeader($name, $value));

  }

  /**

   * Add a new ParameterizedHeader with $name, $value and $params.

   * 

   * @param string $name

   * @param string $value

   * @param array $params

   */

  public function addParameterizedHeader($name, $value = null,

    $params = array())

  {

    $this->_storeHeader($name,

      $this->_factory->createParameterizedHeader($name, $value,

      $params));

  }

  /**

   * Add a new ID header for Message-ID or Content-ID.

   * 

   * @param string $name

   * @param string|array $ids

   */

  public function addIdHeader($name, $ids = null)

  {

    $this->_storeHeader($name, $this->_factory->createIdHeader($name, $ids));

  }

  /**

   * Add a new Path header with an address (path) in it.

   * 

   * @param string $name

   * @param string $path

   */

  public function addPathHeader($name, $path = null)

  {

    $this->_storeHeader($name, $this->_factory->createPathHeader($name, $path));

  }

  /**

   * Returns true if at least one header with the given $name exists.

   * 

   * If multiple headers match, the actual one may be specified by $index.

   * 

   * @param string $name

   * @param int $index

   * 

   * @return boolean

   */

  public function has($name, $index = 0)

  {

    $lowerName = strtolower($name);

    return array_key_exists($lowerName, $this->_headers)

      && array_key_exists($index, $this->_headers[$lowerName]);

  }

  /**

   * Set a header in the HeaderSet.

   * 

   * The header may be a previously fetched header via {@link get()} or it may

   * be one that has been created separately.

   * 

   * If $index is specified, the header will be inserted into the set at this

   * offset.

   * 

   * @param Swift_Mime_Header $header

   * @param int $index

   */

  public function set(Swift_Mime_Header $header, $index = 0)

  {

    $this->_storeHeader($header->getFieldName(), $header, $index);

  }

  /**

   * Get the header with the given $name.

   * 

   * If multiple headers match, the actual one may be specified by $index.

   * Returns NULL if none present.

   * 

   * @param string $name

   * @param int $index

   * 

   * @return Swift_Mime_Header

   */

  public function get($name, $index = 0)

  {

    if ($this->has($name, $index))

    {

      $lowerName = strtolower($name);

      return $this->_headers[$lowerName][$index];

    }

  }

  /**

   * Get all headers with the given $name.

   * 

   * @param string $name

   * 

   * @return array

   */

  public function getAll($name = null)

  {

    if (!isset($name))

    {

      $headers = array();

      foreach ($this->_headers as $collection)

      {

        $headers = array_merge($headers, $collection);

      }

      return $headers;

    }

    $lowerName = strtolower($name);

    if (!array_key_exists($lowerName, $this->_headers))

    {

      return array();

    }

    return $this->_headers[$lowerName];

  }

  /**

   * Remove the header with the given $name if it's set.

   * 

   * If multiple headers match, the actual one may be specified by $index.

   * 

   * @param string $name

   * @param int $index

   */

  public function remove($name, $index = 0)

  {

    $lowerName = strtolower($name);

    unset($this->_headers[$lowerName][$index]);

  }

  /**

   * Remove all headers with the given $name.

   * 

   * @param string $name

   */

  public function removeAll($name)

  {

    $lowerName = strtolower($name);

    unset($this->_headers[$lowerName]);

  }

  /**

   * Create a new instance of this HeaderSet.

   * 

   * @return Swift_Mime_HeaderSet

   */

  public function newInstance()

  {

    return new self($this->_factory);

  }

  /**

   * Define a list of Header names as an array in the correct order.

   * 

   * These Headers will be output in the given order where present.

   * 

   * @param array $sequence

   */

  public function defineOrdering(array $sequence)

  {

    $this->_order = array_flip(array_map('strtolower', $sequence));

  }

  /**

   * Set a list of header names which must always be displayed when set.

   * 

   * Usually headers without a field value won't be output unless set here.

   * 

   * @param array $names

   */

  public function setAlwaysDisplayed(array $names)

  {

    $this->_required = array_flip(array_map('strtolower', $names));

  }

  /**

   * Notify this observer that the entity's charset has changed.

   * 

   * @param string $charset

   */

  public function charsetChanged($charset)

  {

    $this->setCharset($charset);

  }

  /**

   * Returns a string with a representation of all headers.

   * 

   * @return string

   */

  public function toString()

  {

    $string = '';

    $headers = $this->_headers;

    if ($this->_canSort())

    {

      uksort($headers, array($this, '_sortHeaders'));

    }

    foreach ($headers as $collection)

    {

      foreach ($collection as $header)

      {

        if ($this->_isDisplayed($header) || $header->getFieldBody() != '')

        {

          $string .= $header->toString();

        }

      }

    }

    return $string;

  }

  /**

   * Returns a string representation of this object.

   *

   * @return string

   *

   * @see toString()

   */

  public function __toString()

  {

    return $this->toString();

  }

  // -- Private methods

  /** Save a Header to the internal collection */

  private function _storeHeader($name, Swift_Mime_Header $header, $offset = null)

  {

    if (!isset($this->_headers[strtolower($name)]))

    {

      $this->_headers[strtolower($name)] = array();

    }

    if (!isset($offset))

    {

      $this->_headers[strtolower($name)][] = $header;

    }

    else

    {

      $this->_headers[strtolower($name)][$offset] = $header;

    }

  }

  /** Test if the headers can be sorted */

  private function _canSort()

  {

    return count($this->_order) > 0;

  }

  /** uksort() algorithm for Header ordering */

  private function _sortHeaders($a, $b)

  {

    $lowerA = strtolower($a);

    $lowerB = strtolower($b);

    $aPos = array_key_exists($lowerA, $this->_order)

      ? $this->_order[$lowerA]

      : -1;

    $bPos = array_key_exists($lowerB, $this->_order)

      ? $this->_order[$lowerB]

      : -1;

    if ($aPos == -1)

    {

      return 1;

    }

    elseif ($bPos == -1)

    {

      return -1;

    }

    return ($aPos < $bPos) ? -1 : 1;

  }

  /** Test if the given Header is always displayed */

  private function _isDisplayed(Swift_Mime_Header $header)

  {

    return array_key_exists(strtolower($header->getFieldName()), $this->_required);

  }

  /** Notify all Headers of the new charset */

  private function _notifyHeadersOfCharset($charset)

  {

    foreach ($this->_headers as $headerGroup)

    {

      foreach ($headerGroup as $header)

      {

        $header->setCharset($charset);

      }

    }

  }

}