Web.php

<?php
/**
 * © 2010 frederic.glorieux@fictif.org et École nationale des chartes
 * © 2012 frederic.glorieux@fictif.org
 * © 2014 frederic.glorieux@fictif.org et LABEX OBVIL
 * LGPL http://www.gnu.org/licenses/lgpl.html
 *
 * This program is a free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License
 * http://www.gnu.org/licenses/lgpl.html
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 */
/**
 * Tools to deal with PHP Http oddities
 */
if ( get_magic_quotes_gpc() ) {
  function stripslashes_gpc( &$value ) {
    $value = stripslashes( $value );
  }
  array_walk_recursive( $_GET, 'stripslashes_gpc' );
  array_walk_recursive( $_POST, 'stripslashes_gpc' );
  array_walk_recursive( $_COOKIE, 'stripslashes_gpc' );
  array_walk_recursive( $_REQUEST, 'stripslashes_gpc' );
}
class Teinte_Web {
  /** web parameters */
  static $pars;
  /** pathinfo, relative to base application */
  static $pathinfo;
  /** relative path to base application, calculated with pathinfo */
  static $basehref;
  /** Content-Type header */
  static $mime = array(
    "css"  => 'text/css; charset=UTF-8',
    "epub" => 'application/epub+zip',
    "html" => 'text/html; charset=UTF-8',
    "iramuteq" => "text/plain; charset=UTF-8",
    "jpg"  => 'image/jpeg',
    "js"  => 'text/javascript; charset=UTF-8',
    "md" => "text/plain; charset=UTF-8",
    "markdown" => "text/plain; charset=UTF-8",
    "naked" => "text/plain; charset=UTF-8",
    "png"  => 'image/png',
    "xml"  => 'text/xml',
    "xhtml" => 'text/html; charset=UTF-8',
  );
  /** Langs */
  static $langs=array(
    "en" => "English",
    "fr" => "Français",
  );
  /** lang found */
  static $lang;
  /**
   * Give pathinfo with priority order of different values.
   * The possible variables are not equally robust
   *
   * http://localhost/~user/teipot/doc/install&sons?a=1&a=2#ancre
   *
   * — $_SERVER['REQUEST_URI'] OK /~user/teipot/doc/install&sons?a=1&a=2
   * — $_SERVER['SCRIPT_NAME'] OK /~user/teipot/index.php
   * — $_SERVER['PHP_SELF'] /~user/teipot/index.php/doc/install&sons (not always given by mod_rewrite)
   * — $_SERVER['PATH_INFO'] sometimes unavailable, ex: through mod_rewrite /doc/install&sons
   * — $_SERVER['SCRIPT_URI'] sometimes, ex : http://teipot.x10.mx/install&bon
   * — $_SERVER['PATH_ORIG_INFO'] found on the web
   *
   */
  public static function pathinfo()
  {
    if (self::$pathinfo) return self::$pathinfo;
    $pathinfo = "";
    if (!isset($_SERVER['REQUEST_URI'])) return $pathinfo; // command line
    list($request) = explode('?', $_SERVER['REQUEST_URI']);
    if(strpos($request, '%') !== false) $request = urldecode($request);
    if (strpos($request, $_SERVER['SCRIPT_NAME']) === 0)
      $pathinfo = substr($request, strlen($_SERVER['SCRIPT_NAME']));
    else if (strpos($request, dirname($_SERVER['SCRIPT_NAME'])) === 0)
      $pathinfo = substr($request, strlen(dirname($_SERVER['SCRIPT_NAME'])));
    // if nothing found, try other variables
    if ($pathinfo); // something found, keep it
    else if (isset($_SERVER['PATH_ORIG_INFO'])) $pathinfo = $_SERVER['PATH_ORIG_INFO'];
    else if (isset($_SERVER['PATH_INFO'])) $pathinfo = $_SERVER['PATH_INFO'];
    else if (isset($_REQUEST['id'])) $pathinfo = $_REQUEST['id'];
    // should I trim last / ?
    $pathinfo = ltrim($pathinfo, '/');
    $pathinfo = preg_replace('@/+@', '/', $pathinfo);
    // html injection ?
    $pathinfo = strip_tags($pathinfo);
    self::$pathinfo = $pathinfo;
    return self::$pathinfo;
  }
  /**
   * Relative path to context
   */
  public static function basehref( $path=null )
  {
    if ($path) { // return a result, no store
      $path = preg_replace('@/+@', '/', ltrim($path, '/'));
      $path = str_repeat("../", substr_count($path, '/'));
      if (!$path) $path="./"; // with /toto, go up with ./
      return $path;
    }
    if (isset(self::$basehref)) return self::$basehref;
    $pathinfo = self::pathinfo();
    self::$basehref = str_repeat("../", substr_count($pathinfo, '/'));
    if (!self::$basehref) self::$basehref="./"; // with /toto, go up with ./
    return self::$basehref;
  }
  /**
   * Handle repeated parameters values, especially in multiple select.
   * $_REQUEST propose a strange PHP centric interpretation of http protocol, with the bracket keys
   * &lt;select name="var[]">
   *
   * $query : optional, a "query string" ?cl%C3%A9=%C3%A9%C3%A9&param=valeur1&param=&param=valeur2
   * return : Array (
   *   "clé" => array("éé"),
   *   "param" => array("valeur1", "", "valeur2")
   * )
   */
  public static function pars( $name = FALSE, $expire = 0, $pattern = null, $default = null, $query = FALSE )
  {
    // store params array extracted from query
    if (!self::$pars) {
      if (!$query) $query = Teinte_Web::query();
      // populate an array
      self::$pars = array();
      $a = explode('&', $query);
      foreach ($a as $p) {
        if (!$p) continue;
        if (!strpos($p,'=')) continue;
        list($k, $v) = preg_split('/=/', $p);
        $k = urldecode($k);
        $v = urldecode($v);
        // seems ISO, translate accents
        if (preg_match('/[\xC0-\xFD]/', $k+$v)) {
          $k = utf8_encode ($k);
          $v = utf8_encode ($v);
        }
        self::$pars[$k][] = $v;
      }
    }
    // no key requested, return all params, do not store cookies
    if (!$name) return self::$pars;
    // a param is requested, values found
    else if (isset(self::$pars[$name])) $pars = self::$pars[$name];
    // no param for this name
    else $pars = array();


    // no cookie store requested
    if(!$expire);
    // if empty ?, delete cookie
    else if (count($pars)==1 && !$pars[0]) {
      setcookie($name);
    }
    // if a value, set cookie, do not $_COOKIE[$name] = $value
    else if (count($pars)) {
      // if a number
      if ($expire > 60) setcookie($name, serialize($pars), time()+ $expire);
      // session time
      else setcookie($name, serialize($pars));
    }
    // if cookie stored, load it
    else if(isset($_COOKIE[$name])) $pars = unserialize($_COOKIE[$name]);
    // validate
    if ($pattern) {
      $newPars = array();
      foreach($pars as $value) if (preg_match($pattern, $value)) $newPars[] = $value;
      $pars = $newPars;
    }
    // default
    if (count($pars));
    else if (!$default);
    else if (is_array($default)) $pars = $default;
    else $pars = array($default);
    return $pars;
  }

  /**
   * Search for a lang in an accpted list
   */
  public static function lang( $langs=null )
  {
    if (!$langs || !is_array($langs) || !count($langs)) $langs = self::$langs;
    // check browser request
    $lang=false;
    // http param, set a lang
    if (isset($_GET['lang'])) {
      // empty value, reset cookie
      if(!$_GET['lang']) setcookie("lang", "", time() - 3600);
      // lang not available, do nothing
      else if (!isset($langs[$_GET['lang']]));
      // language requested should be available
      else {
        $lang=$_GET['lang'];
        setcookie ( "lang", $lang);
      }
    }
    // coookie persistancy
    if (!$lang && isset($_COOKIE['lang'])) {
      // language in cookie is not available, maybe setted from elsewhere in the site, do nothing
      if(!isset($langs[$_COOKIE['lang']]));
      else $lang=$_COOKIE['lang'];
    }
    // browser request
    if(!$lang) {
      $http_accept_language = isset($_SERVER['HTTP_ACCEPT_LANGUAGE']) ? $_SERVER['HTTP_ACCEPT_LANGUAGE'] : '';
      preg_match_all("/(\w\w)(-\w+)*/", $http_accept_language, $matches);
      // array_values() reindex the keys starting at 0
      $accepted=array_values(array_intersect(array_keys(array_flip($matches[1])), array_keys($langs)));
      if(isset($accepted[0])) $lang=$accepted[0];
    }
    // no lang found, take the first lang available
    if(!$lang) {
      reset($langs);
      $lang=key($langs);
    }
    self::$lang = $lang;
    return self::$lang;
  }
  /**
   * build a clean query string from get or post, especially
   * to get multiple params from select
   *
   * query: ?A=1&A=2&A=&B=3
   * return: ?A=1&A=2&B=3
   * $keep=true : keep empty params -> ?A=1&A=2&A=&B=3
   * $exclude=array() : exclude some parameters
   */
  public static function query( $keep = false, $exclude = array(), $query = null )
  {
    // query given as param
    if ($query) $query = preg_replace( '/&amp;/', '&', $p1);
    // POST
    else if ($_SERVER['REQUEST_METHOD'] == "POST") {
      if (isset($HTTP_RAW_POST_DATA)) $query = $HTTP_RAW_POST_DATA;
      else $query = file_get_contents("php://input");
    }
    // GET
    else $query = $_SERVER['QUERY_STRING'];
    // exclude some params
    if (count($exclude)) $query = preg_replace( '/&('.implode('|',$exclude).')=[^&]*/', '', '&'.$query);
    // delete empty params
    if (!$keep) $query = preg_replace( array('/[^&=]+=&/', '/&$/'), array('', ''), $query.'&');
    return $query;
  }
  /**
   * Send the best headers for cache, according to the request and a timestamp
   */
  public static function notModified( $file, $expires = null, $force = false )
  {
    if (!$file) return false;
    $filemtime = false;
    // seems already a filemtime
    if (is_int($file)) $filemtime = $file;
    // if array of file, get the newest
    else if (is_array($file)) foreach($file as $f) {
      // if not file exists, no error
      if (!file_exists($f)) continue;
      $i = filemtime($f);
      if ($i && $i > $filemtime) $filemtime = $i;
    }
    else $filemtime = filemtime($file);
    if(!$filemtime) return $filemtime;
    // Default expires
    if (filemtime($_SERVER['SCRIPT_FILENAME']) > $filemtime) {
      $filemtime = filemtime($_SERVER['SCRIPT_FILENAME']);
    }
    $if_modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ? stripslashes($_SERVER['HTTP_IF_MODIFIED_SINCE']) :false;
    // $if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH']) ? stripslashes($_SERVER['HTTP_IF_NONE_MATCH']) : false; // etag
    $modification = gmdate('D, d M Y H:i:s', $filemtime).' GMT';
    // tests for 304
    if($force);
    else if (self::noCache());
    // ($if_none_match && $if_none_match == $etag) ||
    else if ( $if_modified_since == $modification) {
      header('HTTP/1.x 304 Not Modified');
      exit;
    }
    // header("X-Date: ". substr(gmdate('r'), 0, -5).'GMT');
    /*
    // According to google, https://developers.google.com/speed/docs/best-practices/caching
    // exclude etag if last-Modified, and last-Modified is better
    $etag = '"'.md5($modification).'"';
    header("ETag: $etag");
    */
    // it seems there is something to send
    header("Cache control: public"); // for FireFox over https
    header("Last-Modified: $modification");
    // it's good to
    if ($expires) header('Expires: ' . gmdate('D, d M Y H:i:s', time()+$expires) . ' GMT');
  }

  /**
   * If client ask a forced reload.
   */
  public static function noCache()
  {
    // pas de cache en POST
    if ($_SERVER['REQUEST_METHOD'] == 'POST') return 'POST';
    if (isset ($_SERVER['HTTP_PRAGMA']) && stripos($_SERVER['HTTP_PRAGMA'], "no-cache") !== false) return "Pragma: no-cache";
    if (isset ($_SERVER['HTTP_CACHE_CONTROL']) && stripos($_SERVER['HTTP_CACHE_CONTROL'], "no-cache") !== false) return "Cache-Control: no-cache";
    if (isset($_REQUEST['no-cache'])) return '?no-cache=';
    if (isset($_REQUEST['force'])) return '?force=';
    return false;
  }
  /**
   * Get link to un upload file, by key or first one if no key
   * return a file record like ine $_FILES
   * http://php.net/manual/features.file-upload.post-method.php
   */
   public static function upload( $key=null )
   {
    // no post, return nothing
    if ( $_SERVER['REQUEST_METHOD'] != 'POST' ) return false;
    $lang = self::lang(array('en'=>'', 'fr'=>''));
    $mess = array(
      UPLOAD_ERR_INI_SIZE => array(
        'en' => 'The uploaded file exceeds a directive in php.ini; upload_max_filesize='.ini_get('upload_max_filesize').', post_max_size='.ini_get('post_max_size'),
        "fr" => 'Le fichier téléchargé dépasse la limite acceptée par la configuration du serveur (php.ini) ; upload_max_filesize='.ini_get('upload_max_filesize').', post_max_size='.ini_get('post_max_size'),
      ),
      UPLOAD_ERR_FORM_SIZE => array(
        'en' => 'The uploaded file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form.',
        'fr' => 'Le fichier téléchargé dépasse la directive MAX_FILE_SIZE spécifiée dans le formulaire.',
      ),
      UPLOAD_ERR_PARTIAL => array(
        'en' => 'The uploaded file was only partially uploaded. ',
        'fr' => 'Le fichier téléchargé est incomplet',
      ),
      UPLOAD_ERR_NO_FILE => array(
        'en' => 'No file was uploaded.',
        'fr' => 'Pas de fichier téléchargé.',
      ),
      UPLOAD_ERR_NO_TMP_DIR => array(
        'en' => 'Server configuration error, missing a temporary folder.',
        'fr' => 'Erreur de configuration serveur, pas de dossier temporaire.',
      ),
      UPLOAD_ERR_CANT_WRITE => array(
        'en' => 'Server system error, failed to write file to disk.',
        'fr' => 'Erreur système sur le serveur, impossible d’écrire le fichier sur le disque.',
      ),
      UPLOAD_ERR_EXTENSION => array(
        'en' => 'PHP server problem, a PHP extension stopped the file upload.',
        'fr' => 'Erreur de configuration PHP, une extension a arrêté le téléchargement du fichier.',
      ),
      'nokey' => array(
        'en' => "Teinte_Web::upload(), no field $key in submitted form.",
        'fr' => "Teinte_Web::upload(), pas de champ $key dans le formulaire soumis.",
      ),
      'nofile' => array(
        'en' => 'Teinte_Web::upload(), no file found. Too big ? Directives in php.ini: upload_max_filesize='.ini_get('upload_max_filesize').', post_max_size='.ini_get('post_max_size'),
        'fr' => 'Teinte_Web::upload(), pas de fichier trouvé. Trop gros ? Directives php.ini: upload_max_filesize='.ini_get('upload_max_filesize').', post_max_size='.ini_get('post_max_size'),
      ),
    );
    if ($key && !isset($_FILES[$key])) throw new Exception($mess['nokey'][$lang]);
    if ($key) $file = $_FILES[$key];
    else $file = reset($_FILES);
    if (!$file || !is_array($file) || !isset($file['error'])) throw new Exception($mess['nofile'][$lang]);
    // validation, no matter for an exception
    if ($file['error'] == UPLOAD_ERR_NO_FILE) return false;
    if ($file['error']) throw new Exception($mess[$file['error']][$lang]);
    // return the array to have the tmp link, and the original name of the file, and some more useful fields
    $file["filename"] = pathinfo($file['name'], PATHINFO_FILENAME);
    $file["extension"] = pathinfo($file['name'], PATHINFO_EXTENSION);
    return $file;
  }

}

?>