/* 
    * 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
    *
    * 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 org.esigate.xml;
  
  import java.io.FilterWriter;
  import java.io.IOException;
  import java.io.Writer;
  import java.util.Arrays;
  
  import nu.validator.htmlparser.sax.HtmlSerializer;
  
  import org.xml.sax.Attributes;
  import org.xml.sax.SAXException;
  
  /**
   * Serializer that extends HtmlSerializer in order to close properly all html elements the xhtml way.
   * 
   * @author Francois-Xavier Bonnet
   * 
   */
  public class XhtmlSerializer extends HtmlSerializer {
      private static final String[] VOID_ELEMENTS = {"area", "base", "basefont", "bgsound", "br", "col", "command",
              "embed", "frame", "hr", "img", "input", "keygen", "link", "meta", "param", "source", "track", "wbr"};
      private final TagClosingWriter tagClosingWriter;
  
      private static class TagClosingWriter extends FilterWriter {
          private boolean fix = false;
  
          protected TagClosingWriter(Writer out) {
              super(out);
          }
  
          @Override
          public void write(int c) throws IOException {
              if (fix && c == '>') {
                  super.write(' ');
                  super.write('/');
              }
              super.write(c);
          }
  
      }
  
      public XhtmlSerializer(Writer out) {
          this(new TagClosingWriter(out));
      }
  
      private XhtmlSerializer(TagClosingWriter out) {
          super(out);
          this.tagClosingWriter = out;
      }
  
      @Override
      public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException {
          if (Arrays.binarySearch(VOID_ELEMENTS, localName) > -1) {
              tagClosingWriter.fix = true;
          }
          super.startElement(uri, localName, qName, atts);
          tagClosingWriter.fix = false;
      }
  
      @Override
      public void startDocument() {
          // Don't generate DOCTYPE declaration
      }
  
  }