<?php
class http
{
  /** Choose the best choice from user choices.
      Can be used for languages (HTTP_ACCEPT_LANGUAGE), type of pages 
      (HTTP_ACCEPT)...
      Ex. fr, en-gb;q=0.8, en;q=0.7
      Ex. text/html,application/xhtml+xml,application/xml;q=0.9,* /*;q=0.8
      If available is empty, then return the best priority defined by user,
      and throw an exception if nothing is provided for by the user.
      If nothing match, return $default
    */
  function bestChoice ($uservar, $available=array(), $default=FALSE)
  {
    $uservar = str_replace (" ", "", $uservar);
    $userchoices = explode (",", $uservar);
    if (!isset ($userchoices[0]))
    {
      if ($default === FALSE)
        throw new Exception ("No user choice provided to bestChoice", 500);
      return $default;
    }
    // Remove weights (provided by the order of the user)
    // TODO : Reorganise the order if the weights are not in the right order
    foreach ($userchoices as $key=>$val)
    {
      $vals = @explode (";q", $val);
      $userchoices[$key] = $vals[0];
    }

    if (count ($available) === 0)
      return $userchoices[0];

    // Look at the best existing solution
    foreach ($userchoices as $choice)
    {
      foreach ($available as $avail)
      {
        if (strtolower ($avail) === strtolower ($choice))
          return $avail;
        // Case en_US
        $availTmp = str_replace ("_", "-", $avail);
        if (strtolower ($availTmp) === strtolower ($choice))
          return $avail;
        // Case text/xml, application/csv (just compare xml or csv)
        $mimes = explode ("/", $choice);
        if (isset ($mimes[1]) && strtolower ($availTmp) === $mimes[1])
          return $avail;
      }
    }

    // No best solution found. Use the default available solution
    return $default;
  }

  /** Return the associated text for a HTTP code */
  function codetext ($code)
  {
    switch ($code) 
    {
    case 100: $text = 'Continue'; break;
    case 101: $text = 'Switching Protocols'; break;
    case 200: $text = 'OK'; break;
    case 201: $text = 'Created'; break;
    case 202: $text = 'Accepted'; break;
    case 203: $text = 'Non-Authoritative Information'; break;
    case 204: $text = 'No Content'; break;
    case 205: $text = 'Reset Content'; break;
    case 206: $text = 'Partial Content'; break;
    case 300: $text = 'Multiple Choices'; break;
    case 301: $text = 'Moved Permanently'; break;
    case 302: $text = 'Moved Temporarily'; break;
    case 303: $text = 'See Other'; break;
    case 304: $text = 'Not Modified'; break;
    case 305: $text = 'Use Proxy'; break;
    case 400: $text = 'Bad Request'; break;
    case 401: $text = 'Unauthorized'; break;
    case 402: $text = 'Payment Required'; break;
    case 403: $text = 'Forbidden'; break;
    case 404: $text = 'Not Found'; break;
    case 405: $text = 'Method Not Allowed'; break;
    case 406: $text = 'Not Acceptable'; break;
    case 407: $text = 'Proxy Authentication Required'; break;
    case 408: $text = 'Request Time-out'; break;
    case 409: $text = 'Conflict'; break;
    case 410: $text = 'Gone'; break;
    case 411: $text = 'Length Required'; break;
    case 412: $text = 'Precondition Failed'; break;
    case 413: $text = 'Request Entity Too Large'; break;
    case 414: $text = 'Request-URI Too Large'; break;
    case 415: $text = 'Unsupported Media Type'; break;
    case 500: $text = 'Internal Server Error'; break;
    case 501: $text = 'Not Implemented'; break;
    case 502: $text = 'Bad Gateway'; break;
    case 503: $text = 'Service Unavailable'; break;
    case 504: $text = 'Gateway Time-out'; break;
    case 505: $text = 'HTTP Version not supported'; break;
    default:
      exit('Unknown http status code "'.htmlentities ($code).'"');
    }

    return $text;
  }
}