/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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
 *
 * http://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 nokogiri.internals.c14n;

import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;
//import nokogiri.internals.org.apache.xml.security.exceptions.XMLSecurityException;
//import nokogiri.internals.org.apache.xml.security.transforms.TransformParam;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

/**
 * This Object serves as Content for the ds:Transforms for exclusive
 * Canonicalization.
 * <BR />
 * It implements the {@link Element} interface
 * and can be used directly in a DOM tree.
 *
 * @author Christian Geuer-Pollmann
 */
//public class InclusiveNamespaces extends ElementProxy implements TransformParam {
public class InclusiveNamespaces extends ElementProxy
{

  /** Field _TAG_EC_INCLUSIVENAMESPACES */
  public static final String _TAG_EC_INCLUSIVENAMESPACES =
    "InclusiveNamespaces";

  /** Field _ATT_EC_PREFIXLIST */
  public static final String _ATT_EC_PREFIXLIST = "PrefixList";

  /** Field ExclusiveCanonicalizationNamespace */
  public static final String ExclusiveCanonicalizationNamespace =
    "http://www.w3.org/2001/10/xml-exc-c14n#";

  /**
   * Constructor XPathContainer
   *
   * @param doc
   * @param prefixList
   */
  public
  InclusiveNamespaces(Document doc, String prefixList)
  {
    this(doc, InclusiveNamespaces.prefixStr2Set(prefixList));
  }

  /**
   * Constructor InclusiveNamespaces
   *
   * @param doc
   * @param prefixes
   */
  public
  InclusiveNamespaces(Document doc, Set<String> prefixes)
  {
    super(doc);

    SortedSet<String> prefixList;
    if (prefixes instanceof SortedSet<?>) {
      prefixList = (SortedSet<String>)prefixes;
    } else {
      prefixList = new TreeSet<String>(prefixes);
    }

    StringBuilder sb = new StringBuilder(prefixList.size() * 8);
    for (String prefix : prefixList) {
      if (prefix.equals("xmlns")) {
        sb.append("#default ");
      } else {
        sb.append(prefix).append(' ');
      }
    }
    int last = sb.length() - 1;
    while (last >= 0 && sb.charAt(last) == ' ') { sb.setLength(last--); } // trim

    this.constructionElement.setAttributeNS(null, InclusiveNamespaces._ATT_EC_PREFIXLIST, sb.toString());
  }

  /**
   * Constructor InclusiveNamespaces
   *
   * @param element
   * @param BaseURI
   * @throws XMLSecurityException
   */
  public
  InclusiveNamespaces(Element element, String BaseURI)
  throws CanonicalizationException
  {
    super(element, BaseURI);
  }

  /**
   * Method getInclusiveNamespaces
   *
   * @return The Inclusive Namespace string
   */
  public String
  getInclusiveNamespaces()
  {
    return this.constructionElement.getAttributeNS(null, InclusiveNamespaces._ATT_EC_PREFIXLIST);
  }

  /**
   * Decodes the <code>inclusiveNamespaces</code> String and returns all
   * selected namespace prefixes as a Set. The <code>#default</code>
   * namespace token is represented as an empty namespace prefix
   * (<code>"xmlns"</code>).
   * <BR/>
   * The String <code>inclusiveNamespaces=" xenc    ds #default"</code>
   * is returned as a Set containing the following Strings:
   * <UL>
   * <LI><code>xmlns</code></LI>
   * <LI><code>xenc</code></LI>
   * <LI><code>ds</code></LI>
   * </UL>
   *
   * @param inclusiveNamespaces
   * @return A set to string
   */
  public static SortedSet<String>
  prefixStr2Set(String inclusiveNamespaces)
  {
    SortedSet<String> prefixes = new TreeSet<String>();

    if ((inclusiveNamespaces == null) || (inclusiveNamespaces.length() == 0)) {
      return prefixes;
    }

    String[] tokens = inclusiveNamespaces.split("\\s");
    for (String prefix : tokens) {
      if (prefix.equals("#default")) {
        prefixes.add("xmlns");
      } else {
        prefixes.add(prefix);
      }
    }

    return prefixes;
  }

  /**
   * Method getBaseNamespace
   *
   * @inheritDoc
   */
  public String
  getBaseNamespace()
  {
    return InclusiveNamespaces.ExclusiveCanonicalizationNamespace;
  }

  /**
   * Method getBaseLocalName
   *
   * @inheritDoc
   */
  public String
  getBaseLocalName()
  {
    return InclusiveNamespaces._TAG_EC_INCLUSIVENAMESPACES;
  }
}
