/*
    * Copyright (c) 2002-2025 Gargoyle Software Inc.
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    * https://www.apache.org/licenses/LICENSE-2.0
    *
    * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.htmlunit.platform.util;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Objects;
  
  import org.apache.xerces.dom.DeferredDocumentImpl;
  import org.apache.xerces.dom.DeferredNode;
  import org.htmlunit.platform.XmlUtilsHelperAPI;
  import org.w3c.dom.Document;
  import org.w3c.dom.NamedNodeMap;
  import org.w3c.dom.Node;
  
  /**
   * <span style="color:red">INTERNAL API - SUBJECT TO CHANGE AT ANY TIME - USE AT YOUR OWN RISK.</span><br>
   *
   * Special processing if the Xerces parser is in use.
   *
   * @author Ronald Brill
   */
  public final class XmlUtilsXercesHelper implements XmlUtilsHelperAPI {
  
      // private static final Log LOG = LogFactory.getLog(XmlUtilsXerces.class);
  
      /**
       * Ctor.
       */
      public XmlUtilsXercesHelper() {
          // Force eager loading of classes in order to flush out any linkage errors early
          Objects.hash(DeferredDocumentImpl.class, DeferredNode.class);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public Map<Integer, List<String>> getAttributesOrderMap(final Document document) {
          if (document instanceof DeferredDocumentImpl) {
              final Map<Integer, List<String>> map = new HashMap<>();
              final DeferredDocumentImpl deferredDocument = (DeferredDocumentImpl) document;
              final int fNodeCount = getPrivate(deferredDocument, "fNodeCount");
              for (int i = 0; i < fNodeCount; i++) {
                  final int type = deferredDocument.getNodeType(i, false);
                  if (type == Node.ELEMENT_NODE) {
                      int attrIndex = deferredDocument.getNodeExtra(i, false);
                      final List<String> attributes = new ArrayList<>();
                      map.put(i, attributes);
                      while (attrIndex != -1) {
                          attributes.add(deferredDocument.getNodeName(attrIndex, false));
                          attrIndex = deferredDocument.getPrevSibling(attrIndex, false);
                      }
                  }
              }
              return map;
          }
          return null;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public int getIndex(final NamedNodeMap namedNodeMap, final Map<Integer, List<String>> attributesOrderMap,
              final Node element, final int requiredIndex) {
          if (attributesOrderMap != null && element instanceof DeferredNode) {
              final int elementIndex = ((DeferredNode) element).getNodeIndex();
              final List<String> attributesOrderList = attributesOrderMap.get(elementIndex);
              if (attributesOrderList != null) {
                  final String attributeName = attributesOrderList.get(requiredIndex);
                  for (int i = 0; i < namedNodeMap.getLength(); i++) {
                      if (namedNodeMap.item(i).getNodeName().equals(attributeName)) {
                          return i;
                      }
                  }
              }
              return requiredIndex;
          }
          return -1;
      }
  }