<?php
/**
 * Subsys_JsHttpRequest_Php: PHP backend for JavaScript DHTML loader.
 * (C) 2005 Dmitry Koterov, http://forum.dklab.ru/users/DmitryKoterov/
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * See http://www.gnu.org/copyleft/lesser.html
 *
 * Do not remove this comment if you want to use the script!
 * Не удаляйте данный комментарий, если вы хотите использовать скрипт!
 *
 * This backend library also supports POST requests additionally to GET.
 *
 * @author Dmitry Koterov
 * @version 3.35
 */

class Subsys_JsHttpRequest_Php
{
  var $SCRIPT_ENCODING = "windows-1251";
  var $SCRIPT_DECODE_MODE = '';
  var $UNIQ_HASH;
  var $SCRIPT_ID;
  var $LOADER = null;
  var $QUOTING = null;

  /**
   * Constructor.
   *
   * Create new Subsys_JsHttpRequest_Php backend object and attach it
   * to script output buffer. As a result - script will always return
   * correct JavaScript code, even in case of fatal errors.
   */
  function Subsys_JsHttpRequest_Php($enc)
  {
    // QUERY_STRING is in form: PHPSESSID=<sid>&a=aaa&b=bbb&<id>
    // where <id> is request ID, <sid> - session ID (if present),
    // PHPSESSID - session parameter name (by default = "PHPSESSID").

    // Parse QUERY_STRING wrapper format.
    $this->LOADER = "SCRIPT";
    if (preg_match('/(\d+)((?:-\w+)?)$/s', $_SERVER['QUERY_STRING'], $m))
    {
      $this->SCRIPT_ID = $m[1];
      // XMLHttpRequest is used if URI ends with "&".
      if ($m[2] == '-xml')
        $this->LOADER = "XMLHttpRequest";
    }
    else
    {
      $this->SCRIPT_ID = 0;
    }

    // Start OB handling early.
    $this->UNIQ_HASH = md5(microtime().getmypid());
    ini_set('error_prepend_string', ini_get('error_prepend_string').$this->UNIQ_HASH);
    ini_set('error_append_string',  ini_get('error_append_string') .$this->UNIQ_HASH);
    ob_start(array(&$this, "_obHandler"));

    // Set up encoding.
    $this->setEncoding($enc);

    // Check if headers are already sent (see Content-Type library usage).
    // If true - generate debug message and exit.
    $file = $line = null;
    if (headers_sent($file, $line))
    {
      trigger_error(
        "HTTP headers are already sent" . ($line !== null? " in $file on line $line" : "") . ". "
          . "Possibly you have extra spaces (or newlines) before first line of the script or any library. "
          . "Please note that Subsys_JsHttpRequest uses its own Content-Type header and fails if "
          . "this header cannot be set. See header() function documentation for details",
          E_USER_ERROR
      );
      exit();
    }
  }


  /**
   * string getJsCode()
   *
   * Return JavaScript part of library.
   */
  function getJsCode()
  {
    return file_get_contents(dirname(__FILE__).'/Js.js');
  }


  /**
   * void setEncoding(string $encoding)
   *
   * Set active script encoding & correct QUERY_STRING according to it.
   * Examples:
   *   "windows-1251"          - set plain encoding (non-windows characters,
   *                             e.g. hieroglyphs, are totally ignored)
   *   "windows-1251 entities" - set windows encoding, BUT additionally replace:
   *                             "&"         ->  "&amp;"
   *                             hieroglyph  ->  &#XXXX; entity
   */
  function setEncoding($enc)
  {
    // Parse encoding.
    preg_match('/^(\S*)(?:\s+(\S*))$/', $enc, $p);
    $this->SCRIPT_ENCODING    = strtolower(@$p[1]? $p[1] : $enc);
    $this->SCRIPT_DECODE_MODE = @$p[2]? $p[2] : '';
    // Manually parse QUERY_STRING because of damned Unicode's %uXXXX.
    $this->_correctQueryString();
  }


  /**
   * string quoteInput(string $input)
   *
   * Quote string according to input decoding mode.
   * If entities is used (see setEncoding()), no '&' character is quoted,
   * only '"', '>' and '<' (we presume than '&' is already quoted by
   * input reader function).
   *
   * Use this function INSTEAD of htmlspecialchars() for $_GET data
   * in your scripts.
   */
  function quoteInput($s)
  {
    if ($this->SCRIPT_DECODE_MODE == 'entities')
      return str_replace(array('"', '<', '>'), array('&quot;', '&lt;', '&gt;'), $s);
    else
      return htmlspecialchars($s);
  }


  /**
   * Convert PHP scalar, array or hash to JS scalar/array/hash.
   */
  function php2js($a)
  {
    if (is_null($a)) return 'null';
    if ($a === false) return 'false';
    if ($a === true) return 'true';
    if (is_scalar($a))
    {
      $a = addslashes($a);
      $a = str_replace("\n", '\n', $a);
      $a = str_replace("\r", '\r', $a);
      $a = preg_replace('{(</)(script)}i', "$1'+'$2", $a); // for FORM loader
      return "'$a'";
    }
    $isList = true;
    for ($i=0, reset($a); $i<count($a); $i++, next($a))
     if (key($a) !== $i)
     {
       $isList = false; break;
     }
    $result = array();
    if ($isList)
    {
      foreach ($a as $v)
        $result[] = Subsys_JsHttpRequest_Php::php2js($v);
      return '[ ' . join(',', $result) . ' ]';
    }
    else
    {
      foreach ($a as $k=>$v)
        $result[] = Subsys_JsHttpRequest_Php::php2js($k) . ': ' . Subsys_JsHttpRequest_Php::php2js($v);
      return '{ ' . join(',', $result) . ' }';
    }
  }


  /**
   * Internal methods.
   */

  /**
   * Parse & decode QUERY_STRING.
   */
  function _correctQueryString()
  {
    // ATTENTION!!!
    // HTTP_RAW_POST_DATA is only accessible when Content-Type of POST request
    // is NOT default "application/x-www-form-urlencoded"!!!
    // Library frontend sets "application/octet-stream" for that purpose,
    // see JavaScript code.
    foreach (array('_GET'=>$_SERVER['QUERY_STRING'], '_POST'=>@$GLOBALS['HTTP_RAW_POST_DATA']) as $dst=>$src)
    {
      if (isset($GLOBALS[$dst]))
      {
        // First correct all 2-byte entities.
        $s = preg_replace('/%(?!5B)(?!5D)([0-9a-f]{2})/si', '%u00\\1', $src);
        // Now we can use standard parse_str() with no worry!
        $data = null;
        parse_str($s, $data);
        $GLOBALS[$dst] = $this->_ucs2EntitiesDecode($data);
      }
    }
    $_REQUEST =
      (isset($_COOKIE)? $_COOKIE : array()) +
      (isset($_POST)? $_POST : array()) +
      (isset($_GET)? $_GET : array());
    if (ini_get('register_globals'))
    {
      // TODO?
    }
  }


  /**
   * Called in case of error too!
   */
  function _obHandler($text)
  {
    // Check for error.
    if (preg_match('{'.$this->UNIQ_HASH.'(.*?)'.$this->UNIQ_HASH.'}sx', $text))
    {
      $text = str_replace($this->UNIQ_HASH, '', $text);
      $this->WAS_ERROR = 1;
    }
    // Content-type header.
    // In XMLHttpRRequest mode we must return text/plain - damned stupid Opera 8.0. :(
    header("Content-type: " . ($this->LOADER=="SCRIPT"? "text/javascript" : "text/plain") . "; charset=" . $this->SCRIPT_ENCODING);
    // Make resulting hash.
    if (!isset($this->RESULT)) $this->RESULT = @$GLOBALS['_RESULT'];
    $result = $this->php2js($this->RESULT);
    $text =
      "// BEGIN Subsys_JsHttpRequest_Js\n" .
        "Subsys_JsHttpRequest_Js.dataReady(\n" .
          "  " . $this->php2js($this->SCRIPT_ID) . ", // this ID is passed from JavaScript frontend\n" .
          "  " . $this->php2js(trim($text)) . ",\n" .
          "  " . $result . "\n" .
          ")\n" .
      "// END Subsys_JsHttpRequest_Js\n" .
      "";
    // $f = fopen("debug", "w"); fwrite($f, $text); fclose($f);
    return $text;
  }


  /**
   * Decode all %uXXXX entities in string or array (recurrent).
   * String must not contain %XX entities - they are ignored!
   */
  function _ucs2EntitiesDecode($data)
  {
    if (is_array($data))
    {
      $d = array();
      foreach ($data as $k=>$v)
      {
        $d[$this->_ucs2EntitiesDecode($k)] = $this->_ucs2EntitiesDecode($v);
      }
      return $d;
    }
    else
    {
      if (strpos($data, '%u') !== false)
      { // improve speed
        $data = preg_replace_callback('/%u([0-9A-F]{1,4})/si', array(&$this, '_ucs2EntitiesDecodeCallback'), $data);
      }
      return $data;
    }
  }


  /**
   * Decode one %uXXXX entity (RE callback).
   */
  function _ucs2EntitiesDecodeCallback($p)
  {
    $hex = $p[1];
    $dec = hexdec($hex);
    if ($dec === "38" && $this->SCRIPT_DECODE_MODE == 'entities')
    {
      // Process "&" separately in "entities" decode mode.
      $c = "&amp;";
    }
    else
    {
      if (is_callable('iconv'))
      {
        $c = @iconv('UCS-2BE', $this->SCRIPT_ENCODING, pack('n', $dec));
      }
      else
      {
        $c = $this->_decUcs2Decode($dec, $this->SCRIPT_ENCODING);
      }
      if (!strlen($c))
      {
        if ($this->SCRIPT_DECODE_MODE == 'entities')
        {
          $c = '&#'.$dec.';';
        }
        else
        {
          $c = '?';
        }
      }
    }
    return $c;
  }


  /**
   * If there is no ICONV, try to decode 1-byte characters manually
   * (for most popular charsets only).
   */

  /**
   * Convert from UCS-2BE decimal to $toEnc.
   */
  function _decUcs2Decode($code, $toEnc)
  {
    if ($code < 128) return chr($code);
    if (isset($this->_encTables[$toEnc]))
    {
      $p = array_search($code, $this->_encTables[$toEnc]);
      if ($p !== false)
        return chr(128 + $p);
    }
    return "";
  }


  /**
   * UCS-2BE -> 1-byte encodings (from #128).
   */
  var $_encTables = array
  (
    'windows-1251' => array
    (
      0x0402, 0x0403, 0x201A, 0x0453, 0x201E, 0x2026, 0x2020, 0x2021,
      0x20AC, 0x2030, 0x0409, 0x2039, 0x040A, 0x040C, 0x040B, 0x040F,
      0x0452, 0x2018, 0x2019, 0x201C, 0x201D, 0x2022, 0x2013, 0x2014,
      0x0098, 0x2122, 0x0459, 0x203A, 0x045A, 0x045C, 0x045B, 0x045F,
      0x00A0, 0x040E, 0x045E, 0x0408, 0x00A4, 0x0490, 0x00A6, 0x00A7,
      0x0401, 0x00A9, 0x0404, 0x00AB, 0x00AC, 0x00AD, 0x00AE, 0x0407,
      0x00B0, 0x00B1, 0x0406, 0x0456, 0x0491, 0x00B5, 0x00B6, 0x00B7,
      0x0451, 0x2116, 0x0454, 0x00BB, 0x0458, 0x0405, 0x0455, 0x0457,
      0x0410, 0x0411, 0x0412, 0x0413, 0x0414, 0x0415, 0x0416, 0x0417,
      0x0418, 0x0419, 0x041A, 0x041B, 0x041C, 0x041D, 0x041E, 0x041F,
      0x0420, 0x0421, 0x0422, 0x0423, 0x0424, 0x0425, 0x0426, 0x0427,
      0x0428, 0x0429, 0x042A, 0x042B, 0x042C, 0x042D, 0x042E, 0x042F,
      0x0430, 0x0431, 0x0432, 0x0433, 0x0434, 0x0435, 0x0436, 0x0437,
      0x0438, 0x0439, 0x043A, 0x043B, 0x043C, 0x043D, 0x043E, 0x043F,
      0x0440, 0x0441, 0x0442, 0x0443, 0x0444, 0x0445, 0x0446, 0x0447,
      0x0448, 0x0449, 0x044A, 0x044B, 0x044C, 0x044D, 0x044E, 0x044F,
    ),
    'koi8-r' => array
    (
      0x2500, 0x2502, 0x250C, 0x2510, 0x2514, 0x2518, 0x251C, 0x2524,
      0x252C, 0x2534, 0x253C, 0x2580, 0x2584, 0x2588, 0x258C, 0x2590,
      0x2591, 0x2592, 0x2593, 0x2320, 0x25A0, 0x2219, 0x221A, 0x2248,
      0x2264, 0x2265, 0x00A0, 0x2321, 0x00B0, 0x00B2, 0x00B7, 0x00F7,
      0x2550, 0x2551, 0x2552, 0x0451, 0x2553, 0x2554, 0x2555, 0x2556,
      0x2557, 0x2558, 0x2559, 0x255A, 0x255B, 0x255C, 0x255d, 0x255E,
      0x255F, 0x2560, 0x2561, 0x0401, 0x2562, 0x2563, 0x2564, 0x2565,
      0x2566, 0x2567, 0x2568, 0x2569, 0x256A, 0x256B, 0x256C, 0x00A9,
      0x044E, 0x0430, 0x0431, 0x0446, 0x0434, 0x0435, 0x0444, 0x0433,
      0x0445, 0x0438, 0x0439, 0x043A, 0x043B, 0x043C, 0x043d, 0x043E,
      0x043F, 0x044F, 0x0440, 0x0441, 0x0442, 0x0443, 0x0436, 0x0432,
      0x044C, 0x044B, 0x0437, 0x0448, 0x044d, 0x0449, 0x0447, 0x044A,
      0x042E, 0x0410, 0x0411, 0x0426, 0x0414, 0x0415, 0x0424, 0x0413,
      0x0425, 0x0418, 0x0419, 0x041A, 0x041B, 0x041C, 0x041d, 0x041E,
      0x041F, 0x042F, 0x0420, 0x0421, 0x0422, 0x0423, 0x0416, 0x0412,
      0x042C, 0x042B, 0x0417, 0x0428, 0x042d, 0x0429, 0x0427, 0x042A
    ),
  );
}

?>
