<?php
/**
 * URI normalization routines.
 *
 * @package OpenID
 * @author JanRain, Inc. <openid@janrain.com>
 * @copyright 2005-2008 Janrain, Inc.
 * @license http://www.apache.org/licenses/LICENSE-2.0 Apache
 */

require_once 'Auth/Yadis/Misc.php';

// from appendix B of rfc 3986 (http://www.ietf.org/rfc/rfc3986.txt)
function Auth_OpenID_getURIPattern() {
  return '&^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?&';
}

function Auth_OpenID_getAuthorityPattern() {
  return '/^([^@]*@)?([^:]*)(:.*)?/';
}

function Auth_OpenID_getEncodedPattern() {
  return '/%([0-9A-Fa-f]{2})/';
}

# gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
#
# sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
#                  / "*" / "+" / "," / ";" / "="
#
# unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
function Auth_OpenID_getURLIllegalCharRE() {
  return "/([^-A-Za-z0-9:\/\?#\[\]@\!\$&'\(\)\*\+,;=\._~\%])/";
}

function Auth_OpenID_getUnreserved() {
  $_unreserved = array();
  for ($i = 0; $i < 256; $i ++) {
    $_unreserved[$i] = false;
  }
  
  for ($i = ord('A'); $i <= ord('Z'); $i ++) {
    $_unreserved[$i] = true;
  }
  
  for ($i = ord('0'); $i <= ord('9'); $i ++) {
    $_unreserved[$i] = true;
  }
  
  for ($i = ord('a'); $i <= ord('z'); $i ++) {
    $_unreserved[$i] = true;
  }
  
  $_unreserved[ord('-')] = true;
  $_unreserved[ord('.')] = true;
  $_unreserved[ord('_')] = true;
  $_unreserved[ord('~')] = true;
  
  return $_unreserved;
}

function Auth_OpenID_getEscapeRE() {
  $parts = array();
  foreach (array_merge(Auth_Yadis_getUCSChars(), Auth_Yadis_getIPrivateChars()) as $pair) {
    list($m, $n) = $pair;
    $parts[] = sprintf("%s-%s", chr($m), chr($n));
  }
  
  return sprintf('[%s]', implode('', $parts));
}

function Auth_OpenID_pct_encoded_replace_unreserved($mo) {
  $_unreserved = Auth_OpenID_getUnreserved();
  
  $i = intval($mo[1], 16);
  if ($_unreserved[$i]) {
    return chr($i);
  } else {
    return strtoupper($mo[0]);
  }
  
  return $mo[0];
}

function Auth_OpenID_pct_encoded_replace($mo) {
  return chr(intval($mo[1], 16));
}

function Auth_OpenID_remove_dot_segments($path) {
  $result_segments = array();
  
  while ($path) {
    if (Auth_Yadis_startswith($path, '../')) {
      $path = substr($path, 3);
    } else if (Auth_Yadis_startswith($path, './')) {
      $path = substr($path, 2);
    } else if (Auth_Yadis_startswith($path, '/./')) {
      $path = substr($path, 2);
    } else if ($path == '/.') {
      $path = '/';
    } else if (Auth_Yadis_startswith($path, '/../')) {
      $path = substr($path, 3);
      if ($result_segments) {
        array_pop($result_segments);
      }
    } else if ($path == '/..') {
      $path = '/';
      if ($result_segments) {
        array_pop($result_segments);
      }
    } else if (($path == '..') || ($path == '.')) {
      $path = '';
    } else {
      $i = 0;
      if ($path[0] == '/') {
        $i = 1;
      }
      $i = strpos($path, '/', $i);
      if ($i === false) {
        $i = strlen($path);
      }
      $result_segments[] = substr($path, 0, $i);
      $path = substr($path, $i);
    }
  }
  
  return implode('', $result_segments);
}

function Auth_OpenID_urinorm($uri) {
  $uri_matches = array();
  preg_match(Auth_OpenID_getURIPattern(), $uri, $uri_matches);
  
  if (count($uri_matches) < 9) {
    for ($i = count($uri_matches); $i <= 9; $i ++) {
      $uri_matches[] = '';
    }
  }
  
  $illegal_matches = array();
  preg_match(Auth_OpenID_getURLIllegalCharRE(), $uri, $illegal_matches);
  if ($illegal_matches) {
    return null;
  }
  
  $scheme = $uri_matches[2];
  if ($scheme) {
    $scheme = strtolower($scheme);
  }
  
  $scheme = $uri_matches[2];
  if ($scheme === '') {
    // No scheme specified
    return null;
  }
  
  $scheme = strtolower($scheme);
  if (! in_array($scheme, array('http', 'https'))) {
    // Not an absolute HTTP or HTTPS URI
    return null;
  }
  
  $authority = $uri_matches[4];
  if ($authority === '') {
    // Not an absolute URI
    return null;
  }
  
  $authority_matches = array();
  preg_match(Auth_OpenID_getAuthorityPattern(), $authority, $authority_matches);
  if (count($authority_matches) === 0) {
    // URI does not have a valid authority
    return null;
  }
  
  if (count($authority_matches) < 4) {
    for ($i = count($authority_matches); $i <= 4; $i ++) {
      $authority_matches[] = '';
    }
  }
  
  list($_whole, $userinfo, $host, $port) = $authority_matches;
  
  if ($userinfo === null) {
    $userinfo = '';
  }
  
  if (strpos($host, '%') !== - 1) {
    $host = strtolower($host);
    $host = preg_replace_callback(Auth_OpenID_getEncodedPattern(), 'Auth_OpenID_pct_encoded_replace', $host);
    // NO IDNA.
  // $host = unicode($host, 'utf-8').encode('idna');
  } else {
    $host = strtolower($host);
  }
  
  if ($port) {
    if (($port == ':') || ($scheme == 'http' && $port == ':80') || ($scheme == 'https' && $port == ':443')) {
      $port = '';
    }
  } else {
    $port = '';
  }
  
  $authority = $userinfo . $host . $port;
  
  $path = $uri_matches[5];
  $path = preg_replace_callback(Auth_OpenID_getEncodedPattern(), 'Auth_OpenID_pct_encoded_replace_unreserved', $path);
  
  $path = Auth_OpenID_remove_dot_segments($path);
  if (! $path) {
    $path = '/';
  }
  
  $query = $uri_matches[6];
  if ($query === null) {
    $query = '';
  }
  
  $fragment = $uri_matches[8];
  if ($fragment === null) {
    $fragment = '';
  }
  
  return $scheme . '://' . $authority . $path . $query . $fragment;
}
