/*
    * Copyright (c) 2002-2026 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.html;
  
  import java.io.PrintWriter;
  
  import org.htmlunit.SgmlPage;
  import org.htmlunit.html.impl.SelectionDelegate;
  import org.htmlunit.html.impl.SimpleSelectionDelegate;
  import org.htmlunit.util.StringUtils;
  import org.w3c.dom.DOMException;
  import org.w3c.dom.Text;
  
  /**
   * Representation of a text node in the HTML DOM.
   *
   * @author David K. Taylor
   * @author Christian Sell
   * @author Rodney Gitzel
   * @author Ahmed Ashour
   * @author Sudhan Moghe
   * @author Philip Graf
   * @author Ronald Brill
   * @author Ronny Shapiro
   */
  public class DomText extends DomCharacterData implements Text {
  
      private SelectionDelegate selectionDelegate_;
      private DoTypeProcessor doTypeProcessor_;
  
      /** The symbolic node name. */
      public static final String NODE_NAME = "#text";
  
      /**
       * Creates an instance of DomText.
       *
       * @param page the Page that contains this element
       * @param data the string data held by this node
       */
      public DomText(final SgmlPage page, final String data) {
          super(page, data);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public DomText splitText(final int offset) {
          if (offset < 0 || offset > getLength()) {
              throw new IllegalArgumentException("offset: " + offset + " data.length: " + getLength());
          }
  
          // split text into two separate nodes
          final DomText newText = createSplitTextNode(offset);
          setData(getData().substring(0, offset));
  
          // insert new text node
          if (getParentNode() != null) {
              getParentNode().insertBefore(newText, getNextSibling());
          }
          return newText;
      }
  
      /**
       * Creates a new text node split from another text node. This method allows
       * the derived type of the new text node to match the original node type.
       *
       * @param offset the character position at which to split the DomText node
       * @return the newly created Text node
       */
      protected DomText createSplitTextNode(final int offset) {
          return new DomText(getPage(), getData().substring(offset));
      }
  
      /**
       * {@inheritDoc}
       * Not yet implemented.
       */
      @Override
      public boolean isElementContentWhitespace() {
          throw new UnsupportedOperationException("DomText.isElementContentWhitespace is not yet implemented.");
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
     public String getWholeText() {
         // I couldn't find a way to have a nearby EntityReference node (either sibling or parent)
         // if this is found, have a look at xerces TextImpl.
         return getNodeValue();
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public Text replaceWholeText(final String content) throws DOMException {
         throw new UnsupportedOperationException("DomText.replaceWholeText is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public short getNodeType() {
         return org.w3c.dom.Node.TEXT_NODE;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getNodeName() {
         return NODE_NAME;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     protected boolean printXml(final String indent, final boolean indentBefore, final PrintWriter printWriter) {
         String data = getData();
         boolean indBefore = indentBefore;
         if (StringUtils.isNotBlank(data)) {
             if (!(getParentNode() instanceof HtmlStyle) || !data.startsWith("<!--") || !data.endsWith("-->")) {
                 data = StringUtils.escapeXmlChars(data);
             }
             printWriter.print(data);
             indBefore = false;
         }
         else if (data != null && !data.isEmpty()) {
             indBefore = true;
         }
         return printChildrenAsXml(indent, indBefore, printWriter);
     }
 
     /**
      * Gives a simple representation to facilitate debugging.
      * @return a simple representation
      */
     @Override
     public String toString() {
         return asNormalizedText();
     }
 
     /**
      * Performs the effective type action, called after the keyPress event and before the keyUp event.
      * @param c the character you with to simulate typing
      * @param htmlElement the element in which typing occurs
      * @param lastType is this the last character to type
      */
     protected void doType(final char c, final HtmlElement htmlElement, final boolean lastType) {
         initDoTypeProcessor();
         doTypeProcessor_.doType(getData(), selectionDelegate_, c, htmlElement, lastType);
     }
 
     /**
      * Performs the effective type action, called after the keyPress event and before the keyUp event.
      *
      * @param keyCode the key code wish to simulate typing
      * @param htmlElement the element in which typing occurs
      * @param lastType is this the last character to type
      */
     protected void doType(final int keyCode, final HtmlElement htmlElement, final boolean lastType) {
         initDoTypeProcessor();
         doTypeProcessor_.doType(getData(), selectionDelegate_, keyCode, htmlElement, lastType);
     }
 
     private void initDoTypeProcessor() {
         if (selectionDelegate_ == null) {
             selectionDelegate_ = new SimpleSelectionDelegate();
             doTypeProcessor_ = new DoTypeProcessor(this);
         }
     }
 
     /**
      * Indicates if the provided character can be "typed" in the element.
      * @param c the character
      * @return {@code true} if it is accepted
      */
     protected boolean acceptChar(final char c) {
         // This range is this is private use area
         // see http://www.unicode.org/charts/PDF/UE000.pdf
         return (c < '\uE000' || c > '\uF8FF') && (c == ' ' || !Character.isWhitespace(c));
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public DomNode cloneNode(final boolean deep) {
         final DomText newnode = (DomText) super.cloneNode(deep);
         selectionDelegate_ = new SimpleSelectionDelegate();
         doTypeProcessor_ = new DoTypeProcessor(this);
 
         return newnode;
     }
 
     /**
      * Moves the selection to the end.
      */
     public void moveSelectionToEnd() {
         initDoTypeProcessor();
         selectionDelegate_.setSelectionStart(getData().length());
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setPrefix(final String prefix) {
         // Empty.
     }
 }