/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"
interface nsIAtom;

[scriptable, uuid(72152f7f-7e8d-43fd-8477-3f29ae8d240d)]
interface nsIXTFAttributeHandler : nsISupports
{
  // If 'false' the given attribute will be handled by the wrapper.
  // Namespaced attributes will always be handled by the wrapper. The
  // set of attributes handled by the attribute handler should remain
  // constant for its complete lifetime.
  boolean handlesAttribute(in nsIAtom name);
  
  void setAttribute(in nsIAtom name, in AString newValue);
  
  void removeAttribute(in nsIAtom name);

  // If the attribute 'name' is unknown the implementation should mark
  // the returned string as being 'null' (i.e. return 'null' in JS;
  // call SetIsVoid(PR_TRUE) in C++) rather than throw an exception.
  // A 'void' result will be translated into the attribute missing
  // by the wrapper. An empty result will be translated into
  // the attribute having no value.
  AString getAttribute(in nsIAtom name);
  
  boolean hasAttribute(in nsIAtom name);
  
  unsigned long getAttributeCount();

  // note that this method should return an *atom* not a string.
  nsIAtom getAttributeNameAt(in unsigned long index);
};