// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

part of $LIBRARYNAME;

$(ANNOTATIONS)$(NATIVESPEC)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS {
$!MEMBERS
  /**
   * Checks to see if the mutation observer API is supported on the current
   * platform.
   */
  static bool get supported {
    return JS('bool',
        '!!(window.MutationObserver || window.WebKitMutationObserver)');
  }

  /**
   * Observes the target for the specified changes.
   *
   * Some requirements for the optional parameters:
   *
   * * Either childList, attributes or characterData must be true.
   * * If attributeOldValue is true then attributes must also be true.
   * * If attributeFilter is specified then attributes must be true.
   * * If characterDataOldValue is true then characterData must be true.
   */
  void observe(Node target,
               {bool childList,
                bool attributes,
                bool characterData,
                bool subtree,
                bool attributeOldValue,
                bool characterDataOldValue,
                List<String> attributeFilter}) {

    // Parse options into map of known type.
    var parsedOptions = _createDict();

    // Override options passed in the map with named optional arguments.
    override(key, value) {
      if (value != null) _add(parsedOptions, key, value);
    }

    override('childList', childList);
    override('attributes', attributes);
    override('characterData', characterData);
    override('subtree', subtree);
    override('attributeOldValue', attributeOldValue);
    override('characterDataOldValue', characterDataOldValue);
    if (attributeFilter != null) {
      override('attributeFilter', _fixupList(attributeFilter));
    }

    _call(target, parsedOptions);
  }

   // TODO: Change to a set when const Sets are available.
  static final _boolKeys =
    const {'childList': true,
           'attributes': true,
           'characterData': true,
           'subtree': true,
           'attributeOldValue': true,
           'characterDataOldValue': true };


  static _createDict() => JS('var', '{}');
  static _add(m, String key, value) { JS('void', '#[#] = #', m, key, value); }
  static _fixupList(list) => list;  // TODO: Ensure is a JavaScript Array.

  // Call native function with no conversions.
  @JSName('observe')
  void _call(target, options) native;

  factory MutationObserver(MutationCallback callback) {
    // Dummy statement to mark types as instantiated.
    JS('MutationObserver|MutationRecord', '0');

    return JS('MutationObserver',
        'new(window.MutationObserver||window.WebKitMutationObserver||'
        'window.MozMutationObserver)(#)',
        convertDartClosureToJS(_wrapBinaryZone(callback), 2));
  }
}