/*
    * 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.parser.future;
  
  import java.io.IOException;
  import java.util.concurrent.Future;
  
  import org.esigate.HttpErrorPage;
  
  /**
   * Handle unknown tag.
   * 
   * @author Alexis thaveau
   */
  public class UnknownElement implements FutureElement {
      /***
       * UnknownElement type.
       */
      public static final FutureElementType TYPE = new FutureElementType() {
  
          private final UnknownElement instance = new UnknownElement();
  
          @Override
          public boolean isStartTag(String tag) {
              return true;
          }
  
          @Override
          public boolean isEndTag(String tag) {
              return false;
          }
  
          @Override
          public FutureElement newInstance() {
              return instance;
          }
  
          @Override
          public boolean isSelfClosing(String tag) {
              return true;
          }
      };
  
      @Override
      public boolean onTagStart(String tag, FutureParserContext ctx) throws IOException, HttpErrorPage {
  
          ctx.characters(new CharSequenceFuture(tag));
          return true;
      }
  
      @Override
      public void onTagEnd(String tag, FutureParserContext ctx) throws IOException, HttpErrorPage {
  
      }
  
      @Override
      public boolean onError(Exception e, FutureParserContext ctx) {
          return false;
      }
  
      @Override
      public void characters(Future<CharSequence> csq) throws IOException {
          throw new UnsupportedOperationException("characters are appended in onTagStart method");
      }
  
      @Override
      public FutureElement getParent() {
          return null;
      }
  }