<?php
/**
 * PHP Reader Library
 *
 * Copyright (c) 2008 The PHP Reader Project Workgroup. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  - Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  - Neither the name of the project workgroup nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @package    php-reader
 * @subpackage ID3
 * @copyright  Copyright (c) 2008 The PHP Reader Project Workgroup
 * @license    http://code.google.com/p/php-reader/wiki/License New BSD License
 * @version    $Id: WXXX.php 105 2008-07-30 14:56:47Z svollbehr $
 */

/**#@+ @ignore */
require_once("ID3/Frame/AbstractLink.php");
require_once("ID3/Encoding.php");
/**#@-*/

/**
 * This frame is intended for URL links concerning the audio file in a similar
 * way to the other "W"-frames. The frame body consists of a description of the
 * string, represented as a terminated string, followed by the actual URL. The
 * URL is always encoded with ISO-8859-1. There may be more than one "WXXX"
 * frame in each tag, but only one with the same description.
 * 
 * @package    php-reader
 * @subpackage ID3
 * @author     Sven Vollbehr <svollbehr@gmail.com>
 * @author     Ryan Butterfield <buttza@gmail.com>
 * @copyright  Copyright (c) 2008 The PHP Reader Project Workgroup
 * @license    http://code.google.com/p/php-reader/wiki/License New BSD License
 * @version    $Rev: 105 $
 */
final class ID3_Frame_WXXX extends ID3_Frame_AbstractLink
  implements ID3_Encoding
{
  /** @var integer */
  private $_encoding = ID3_Encoding::UTF8;
  
  /** @var string */
  private $_description;
  
  /**
   * Constructs the class with given parameters and parses object related data.
   *
   * @param Reader $reader The reader object.
   * @param Array $options The options array.
   */
  public function __construct($reader = null, &$options = array())
  {
    ID3_Frame::__construct($reader, $options);
    
    if ($reader === null)
      return;
    
    $this->_encoding = Transform::fromUInt8($this->_data[0]);
    $this->_data = substr($this->_data, 1);
    
    switch ($this->_encoding) {
    case self::UTF16:
      list($this->_description, $this->_link) = 
        $this->explodeString16($this->_data, 2);
      $this->_description = Transform::fromString16($this->_description);
      break;
    case self::UTF16BE:
        list($this->_description, $this->_link) = 
          $this->explodeString16($this->_data, 2);
        $this->_description = Transform::fromString16BE($this->_description);
      break;
    default:
      list($this->_description, $this->_link) =
        $this->explodeString8($this->_data, 2);
      break;
    }
    $this->_link = implode($this->explodeString8($this->_link, 1), "");
  }
  
  /**
   * Returns the text encoding.
   * 
   * @return integer The encoding.
   */
  public function getEncoding() { return $this->_encoding; }

  /**
   * Sets the text encoding.
   * 
   * @see ID3_Encoding
   * @param integer $encoding The text encoding.
   */
  public function setEncoding($encoding) { $this->_encoding = $encoding; }
  
  /**
   * Returns the link description.
   * 
   * @return string
   */
  public function getDescription() { return $this->_description; }
  
  /**
   * Sets the content description text using given encoding.
   * 
   * @param string $description The content description text.
   * @param integer $encoding The text encoding.
   */
  public function setDescription($description, $encoding = false)
  {
    $this->_description = $description;
    if ($encoding !== false)
      $this->_encoding = $encoding;
  }
  
  /**
   * Returns the frame raw data.
   *
   * @return string
   */
  public function __toString()
  {
    $data = Transform::toUInt8($this->_encoding);
    switch ($this->_encoding) {
    case self::UTF16:
    case self::UTF16LE:
      $data .= Transform::toString16
        ($this->_description, $this->_encoding == self::UTF16 ?
         Transform::MACHINE_ENDIAN_ORDER : Transform::LITTLE_ENDIAN_ORDER) .
        "\0\0";
      break;
    case self::UTF16BE:
      $data .= Transform::toString16BE($this->_description) . "\0\0";
      break;
    default:
      $data .= $this->_description . "\0";
    }
    $this->setData($data . $this->_link);
    return ID3_Frame::__toString();
  }
}