/*
 * DomText.java
 * Copyright (C) 1999-2001 David Brownell
 * Copyright (C) 2004 The Free Software Foundation
 * 
 * This file is part of GNU JAXP, a library.
 *
 * GNU JAXP is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * GNU JAXP is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Linking this library statically or dynamically with other modules is
 * making a combined work based on this library.  Thus, the terms and
 * conditions of the GNU General Public License cover the whole
 * combination.
 *
 * As a special exception, the copyright holders of this library give you
 * permission to link this library with independent modules to produce an
 * executable, regardless of the license terms of these independent
 * modules, and to copy and distribute the resulting executable under
 * terms of your choice, provided that you also meet, for each linked
 * independent module, the terms and conditions of the license of that
 * module.  An independent module is a module which is not derived from
 * or based on this library.  If you modify this library, you may extend
 * this exception to your version of the library, but you are not
 * obliged to do so.  If you do not wish to do so, delete this
 * exception statement from your version. 
 */

package gnu.xml.dom;

import org.w3c.dom.DOMException;
import org.w3c.dom.Text;

/**
 * <p> "Text" implementation.  </p>
 *
 * @author David Brownell 
 * @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
 */
public class DomText
  extends DomCharacterData
  implements Text
{
  
  // NOTE:  deleted unused per-instance "isIgnorable"
  // support to reclaim its space.
  
  /**
   * Constructs a text node associated with the specified
   * document and holding the specified data.
   *
   * <p>This constructor should only be invoked by a Document object
   * as part of its createTextNode functionality, or through a subclass
   * which is similarly used in a "Sub-DOM" style layer. 
   */
  protected DomText(DomDocument owner, String value)
  {
    super(TEXT_NODE, owner, value);
  }

  protected DomText(DomDocument owner, char[] buf, int off, int len)
  {
    super(TEXT_NODE, owner, buf, off, len);
  }

  // Used by DomCDATA
  DomText(short nodeType, DomDocument owner, String value)
  {
    super(nodeType, owner, value);
  }

  DomText(short nodeType, DomDocument owner, char[] buf, int off, int len)
  {
    super(nodeType, owner, buf, off, len);
  }

  /**
   * <b>DOM L1</b>
   * Returns the string "#text".
   */
  // can't be 'final' with CDATA subclassing
  public String getNodeName()
  {
    return "#text";
  }

  /**
   * <b>DOM L1</b>
   * Splits this text node in two parts at the offset, returning
   * the new text node (the sibling with the second part).
   */
  public Text splitText(int offset)
  {
    if (isReadonly())
      {
        throw new DomEx(DomEx.NO_MODIFICATION_ALLOWED_ERR);
      }
    try
      {
        String text = getNodeValue();
        String before = text.substring(0, offset);
        String after = text.substring(offset);
        Text next;
        
        if (getNodeType() == TEXT_NODE)
          {
            next = owner.createTextNode(after);
          }
        else // CDATA_SECTION_NODE
          {
            next = owner.createCDATASection(after);
          }
        
        if (this.next != null)
          {
            parent.insertBefore(next, this.next);
          }
        else
          {
            parent.appendChild(next);
          }
        setNodeValue(before);
        return next;
        
      }
    catch (IndexOutOfBoundsException x)
      {
        throw new DomEx(DomEx.INDEX_SIZE_ERR);
      }
  }
    
  // DOM Level 3
  
  public boolean isElementContentWhitespace()
  {
    if (parent != null)
      {
        DomDoctype doctype = (DomDoctype) owner.getDoctype();
        if (doctype != null)
          {
            DTDElementTypeInfo info =
              doctype.getElementTypeInfo(parent.getNodeName());
            if (info != null)
              {
                if (info.model == null && info.model.indexOf("#PCDATA") != -1)
                  {
                    return false;
                  }
                return getNodeValue().trim().length() == 0;
              }
          }
      }
    return false;
  }

  public String getWholeText()
  {
    DomNode ref = this;
    DomNode ctx;
    for (ctx = previous; ctx != null &&
         (ctx.nodeType == TEXT_NODE || ctx.nodeType == CDATA_SECTION_NODE);
         ctx = ctx.previous)
      {
        ref = ctx;
      }
    StringBuffer buf = new StringBuffer(ref.getNodeValue());
    for (ctx = ref.next; ctx != null &&
         (ctx.nodeType == TEXT_NODE || ctx.nodeType == CDATA_SECTION_NODE);
         ctx = ctx.next)
      {
        buf.append(ctx.getNodeValue());
      }
    return buf.toString ();
  }

  public Text replaceWholeText(String content)
    throws DOMException
  {
    boolean isEmpty = (content == null || content.length () == 0);
    if (!isEmpty)
      {
        setNodeValue(content);
      }
    
    DomNode ref = this;
    DomNode ctx;
    for (ctx = previous; ctx != null &&
         (ctx.nodeType == TEXT_NODE || ctx.nodeType == CDATA_SECTION_NODE);
         ctx = ctx.previous)
      {
        ref = ctx;
      }
    ctx = ref.next;
    if ((isEmpty || ref != this) && parent != null)
      {
        parent.removeChild(ref);
      }
    for (; ctx != null &&
         (ctx.nodeType == TEXT_NODE || ctx.nodeType == CDATA_SECTION_NODE);
         ctx = ref)
      {
        ref = ctx.next;
        if ((isEmpty || ctx != this) && parent != null)
          {
            parent.removeChild(ctx);
          }
      }
    return (isEmpty) ? null : this;
  }
    
}
