class HttpConnection {
  private $host;
  private $port;
  private $headers;
  
  public function __construct($host, $port) {
    $this->host    = $host;
    $this->port    = $port;
    $this->headers = new HeaderList(array(), "\r\n");
  }
  
  public function get($path, $params = array(), $headers = array()) {
    return $this->send($path, 'get', $params, $headers);
  }
  
  public function post($path, $params = array(), $headers = array()) {
    return $this->send($path, 'post', $params, $headers);
  }
  
  public static function serialize_auth($user, $pass) {
    return base64_encode("$user:$pass");
  }
  
  public static function serialize_params($params) {
   $query_string = array();
    foreach ($params as $key => $value) {
      $query_string[] = urlencode($key) . '=' . urlencode($value);
    }
    return implode('&', $query_string);
  }
  
  private function send($path, $method, $params = array(), $headers = array()) {  
    $this->headers->add($headers);  
    $params = self::serialize_params($params);
    
    $this->request = strtoupper($method) . " http://{$this->host}{$path}?{$params} HTTP/1.0\r\n";
    $this->request .= $this->headers->to_s() . "\r\n";    

    if ($fp = fsockopen($this->host, $this->port, $errno, $errstr, 15)) {
      if (fwrite($fp, $this->request)) {
        while (!feof($fp)) {
         $this->response .= fread($fp, 4096);
       }
      }
      fclose($fp);
    } else {
      throw new Exception("could not establish connection with $host");
    }
    
    return $this->parse_response();
  }
  
  private function parse_response() {
    $this->response = str_replace("\r\n", "\n", $this->response);
    list($headers, $body) = explode("\n\n", $this->response, 2);
    $headers = new HeaderList($headers);
    return array('headers' => $headers->to_a(), 'body' => $body, 'code' => $headers->get_response_code());
  }
}

class HeaderList {
  private $headers;
  private $response_code;
  private $linebreak;
  
  public function __construct($headers = array(), $linebreak = "\n") {
    $this->linebreak = $linebreak;
    $this->headers   = $headers;
    if (is_string($this->headers)) {
      $this->parse_headers_string();
    }
  }
  
  public function to_s() {
    $headers = '';
    foreach ($this->headers as $header => $value) {
      $headers .= "$header: $value{$this->linebreak}";
    }
    return $headers;
  }
  
  public function to_a() {
    return $this->headers;
  }
  
  public function __toString() {
    return $this->to_s();
  }
  
  public function add($headers) {
    $this->headers = array_merge($this->headers, $headers);
  }
  
  public function get($header) {
    return $this->headers[$header];
  }
  
  public function get_response_code() {
    return $this->response_code;
  }
  
  private function parse_headers_string() {
    $replace = ($this->linebreak == "\n" ? "\r\n" : "\n");
    $headers = str_replace($replace, $this->linebreak, trim($this->headers));
    $headers = explode($this->linebreak, $headers);
    $this->headers = array();
    if (preg_match('/^HTTP\/\d\.\d (\d{3})/', $headers[0], $matches)) {
      $this->response_code = $matches[1];
      array_shift($headers);
    }
    foreach ($headers as $string) {
      list($header, $value) = explode(': ', $string, 2);
      $this->headers[$header] = $value;
    }
  }
}