/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:  
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Xalan" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation and was
 * originally based on software copyright (c) 1999, Lotus
 * Development Corporation., http://www.lotus.com.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
package org.apache.xalan.stree;

import org.w3c.dom.Node;
import org.w3c.dom.Text;

import org.xml.sax.ContentHandler;
import javax.xml.transform.TransformerException;

import org.apache.xml.utils.FastStringBuffer;

/**
 * <meta name="usage" content="internal"/>
 * Class to hold information about a Text node.
 */
public class TextImpl extends Child implements Text
{

  /** Text from this Text node          */
  protected String m_data;

  /** Start of text from this Text node          */
  protected int m_start;
  
  /** Get the start of text in the text buffer. 
   *  @return the start of text in the text buffer. */
  public int getStartOffsetInBuffer()
  {
    return m_start;
  }

  /** The length of text in the text buffer. */
  protected int m_length;
  
  /** Get the length of text in the text buffer.
   *  @return the length of text in the text buffer. */
  public int getLengthInBuffer()
  {
    return m_length;
  }

  /**
   * Constructor TextImpl
   *
   *
   * @param doc Document object
   * @param data Text from node 
   */
  public TextImpl(DocumentImpl doc, String data)
  {

    super(doc);

    m_data = data;
    m_length = data.length();
    m_start = -1;
  }

  /**
   * Constructor TextImpl
   *
   *
   * @param doc Document object
   * @param ch Array containing text from node 
   * @param start Start location of text in array
   * @param length Length of text in array 
   */
  public TextImpl(DocumentImpl doc, char ch[], int start, int length)
  {

    super(doc);

    // m_data = new String(ch, start, start+length);
    FastStringBuffer fsb = doc.m_chars;

    synchronized(fsb)
    {
      m_start = fsb.length(); // Isolate from internal representation
      m_length = length;
      fsb.append(ch, start, length);
    }
  }

  /**
   * Send content of this text node as a SAX Characters event. Handles both
   * the case where the Text node has stored its data as a local string and
   * that in which the data has been placed in a FastStringBuffer pool.
   *
   * @param ch Content handler to handle SAX events
   *
   * @throws SAXException if the content handler characters event throws a SAXException.
   */
  public void dispatchCharactersEvent(ContentHandler ch) 
    throws org.xml.sax.SAXException
  {

    if (-1 == m_start)
      ch.characters(m_data.toCharArray(), 0, m_data.length());
    else
    {
      synchronized(m_doc.m_chars)
      {
		m_doc.m_chars.sendSAXcharacters(ch,m_start,m_length);
      }
    }
  }

  /**
   * A short integer indicating what type of node this is. The named
   * constants for this value are defined in the org.w3c.dom.Node interface.
   *
   * @return TEXT_NODE node type
   */
  public short getNodeType()
  {
    return Node.TEXT_NODE;
  }

  /**
   * Returns the node name. 
   *
   * @return Text node name 
   */
  public String getNodeName()
  {
    return "#text";
  }

  /**
   * Returns the local part of the qualified name of this node.
   * <br>For nodes created with a DOM Level 1 method, such as
   * <code>createElement</code> from the <code>Document</code> interface,
   * it is <code>null</code>.
   * @since DOM Level 2
   *
   * @return Text node name 
   */
  public String getLocalName()
  {
    return "#text";
  }

  /**
   * Retrieve character data currently stored in this node.
   *
   *
   * @return Text from this text node 
   * @throws DOMExcpetion(DOMSTRING_SIZE_ERR) In some implementations,
   * the stored data may exceed the permitted length of strings. If so,
   * getData() will throw this DOMException advising the user to
   * instead retrieve the data in chunks via the substring() operation.
   */
  public String getData()
  {

    if (null == m_data)
    {
      synchronized(m_doc.m_chars)
      {   
        m_data = m_doc.m_chars.getString(m_start, m_length);
      }
    }

    return m_data;
  }

  /**
   * Report number of characters currently stored in this node's
   * data. It may be 0, meaning that the value is an empty string.
   *
   * @return number of characters in this node's data.
   */
  public int getLength()
  {
    return m_length;
  }

  /**
   * Return the text that constitutes this node's data. 
   *
   *
   * @return this node's data
   */
  public String getNodeValue()
  {

    if (null == m_data)
    {
      synchronized(m_doc.m_chars)
      {   
        m_data = m_doc.m_chars.getString(m_start, m_length);
      }
    }

    return m_data;
  }
  
  /**
   * Append this text to the text of this node.
   *
   *
   * @param ch The characters from the XML document.
   * @param start The start position in the array.
   * @param length The number of characters to read from the array. 
   *
   */
  void appendText(char ch[], int start, int length)
  {   
    if (null == m_data)
    {
      FastStringBuffer fsb = m_doc.m_chars;
      synchronized(fsb)
      {   
        fsb.append(ch, start, length);
      }      
    }
    else
      m_data.concat(ch.toString());
    
    m_length += length;
  }
  
  public boolean isWhitespace()
  {
	  return m_doc.m_chars.isWhitespace(m_start,m_length);
  }
  
}