package org.crosswire.xml;

/**
 * Copyright (c) 2001 CrossWire Bible Society. 
 * Distributable under the terms of the GNU GPL V2.
 */


import java.sql.Timestamp;

import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Node;

 /** The Resolver class contains all
 * the "write" functionality of the XMLBlock, XMLTag,
 * and XMLDataExement classes.
 * All of the "read" functionality of the three listed
 * class can be found in the Resolver interface and
 * classes.
 *
 * @version $Id: LocalXMLResolver.java,v 1.9.2.6 2001/06/13 00:21:01 troy Exp $
 */

public class LocalXMLResolver implements java.io.Serializable, XMLResolver {

     Node node = null;
     XMLMetaData myMetaData = null;


     public LocalXMLResolver(Node node, XMLMetaData xmd) {
		this.node = node;
		this.myMetaData = xmd;
     }

     public LocalXMLResolver(Node node) {
          this.node = node;
     }


     public LocalXMLResolver() {
     }

    /** Sets a value for a tag block (eg. <TAG>VALUE</TAG>) that is a child
     *  of this XMLBlock.  The tag block will be created if it does not exist.
     *  @param key the tag name to find/create and for which to set the value.
     *  @param value the value text to set for the tag block.
     *  @return the XMLDataElement that was set/created.
     */

    public XMLDataElement setValue(String key, String value) {
        XMLDataElement target = null;
        XMLDataElement []elements = LocalXMLProvider.getElements(node, key);
        for (int i = 1; i < elements.length; i++)	// remove all but first
            removeChild(elements[i]);

        if (elements.length > 0) {
            target = elements[0];
            target.setText(value);
        }
        else
            target = createValue(key, value);
        
        setModified();
        
        return target;
    }

    void setModified() { setModified(true); }
    void setModified(boolean val) {
    	Boolean mod = new Boolean(val);
   		node.getOwnerDocument().setUserData("modified", mod, null);
    }
    /** Creates and sets a value for a tag block (eg. &lt;TAG&gt;VALUE&lt;/TAG&gt;) as a
     *  child of this XMLBlock.  The tag block will be created regardless if
     *  another tag block with the same key value already exists.
     *  @param key the tag name to create and for which to set the value.
     *  @param value the value text to set for the tag block.
     *  @return the XMLDataElement that was created.
     */

     public XMLDataElement createValue(String key, String value) {
          XMLDataElement data;
          Node newNode = node.getOwnerDocument().createElement(key);
          node.appendChild(newNode);
          data = new XMLDataElement(newNode);
          data.setText(value);

          setModified();
          return data;
     }

    /** Copies an XMLBlock to this document as a child of this XMLBlock.
     *  @param newBlk the block to import.
     *  @return the new XMLBlock child of this XMLBlock.
     */

     public XMLBlock addBlock(XMLBlock newBlk) {
          XMLBlock localBlock = new XMLBlock(XMLBlock.createXMLBlock(newBlk.toString()));
          //TODO: remove this toString call when next version of xerces released.
          localBlock.toString(); 	// realize entire block before importing (xerces bug 1.3.0)
          Node newNode = node.getOwnerDocument().importNode(localBlock.getNode(), true);
          node.appendChild(newNode);

          setModified();
          return new XMLBlock(newNode);
     }


    /** Creates a new block as a child of this XMLBlock.  The block will be
     *  created regardless if another block with the same key value already
     *  exists.
     *  @param key the tag name to give the newly created block.
     *  @return the XMLBlock that was created.
     */

     public XMLBlock createBlock(String key) {
          Node newNode = node.getOwnerDocument().createElement(key);
          node.appendChild(newNode);
          
          setModified();
          return new XMLBlock(newNode);
     }


    /** Removes a child from this XMLBlock.  All XMLObjects extend from XMLTag,
     *  so sending any XMLObject previously retrieved from this block will
     *  remove it from this block.
     *  @param tag any XMLObject that is a child of this XMLBlock.
     */

     public void removeChild(XMLTag tag) {
          node.removeChild(tag.getNode());
          
          setModified();
     }

/** Start of XMLDataElement method **/

/**
 * This method set the text data for the XMLDataElement.
 *
**/
     public void setText(String text) {
    	 int i;
          for (i = 0; i < node.getChildNodes().getLength(); i++) {
               if (node.getChildNodes().item(i).getNodeType() == Node.TEXT_NODE) {
                    node.getChildNodes().item(i).setNodeValue(text);
                    break;
               }
          }
          if (i == node.getChildNodes().getLength())
        	  node.appendChild(node.getOwnerDocument().createTextNode(text));
          
          setModified();
     }

/** Start of XMLTag methods **/

/**
 * This method sets a named attribute to a specific value
 * @param key attribute name.
 * @param value attribute value.
 *
**/

    public void setAttribute(String key, String value) {
        Document d = node.getOwnerDocument();
        Attr attr = d.createAttribute(key);
        attr.setNodeValue((value==null)?"":value);
        node.getAttributes().setNamedItem(attr);
        if (value == null)  // we still add above to be sure remove doesn't fail
            node.getAttributes().removeNamedItem(key);
        
        setModified();
    }

/**
 * Sets the node.
*/
    public void setNode(Node node) {
        this.node = node;
    }

/**
 * Sets the XMLMetaData.
 */
    public void setXMLMetaData(XMLMetaData xmd) {
        this.myMetaData = xmd;
    }


/******** Default Serialization should work.
    private void writeObject(java.io.ObjectOutputStream out)
    throws IOException
    {
        out.writeObject(node);
    }
    private void readObject(java.io.ObjectInputStream in)
    throws IOException, ClassNotFoundException
    {
        node = (Node) in.readObject();
    }
*****/



/** XMLMetaData Methods */



/** Sets the status of an xmlobject, the four
 *  statuses avaliable are ready = R,
 *  done = D, cancel = C, and
 *  Not Applicable = _
 */
    public void setObjectState(char value) {
            myMetaData.setObjectState(value);
        }


/** Sets one of the three key value for
 *  xmlobject's metadata
 */
        public void setKey(int keyConstant, String value) {
            myMetaData.setKey(keyConstant, value);
        }


/** Sets any of the three Timestamps
 *  for an xmlobject with a
 *  timestamp value.
 */
        public void setTimeStamp(int keyConstant, Timestamp value) {
            myMetaData.setTimeStamp(keyConstant, value);
        }

/** Sets the Status of the xmlobject
 */
        public void setStatus(String sm) {
            myMetaData.setStatus(sm);
        }

/** Sets the StatusMaskBit
 */
        public void setStatusMaskBit(int bit, char option){
           myMetaData.setStatusMaskBit(bit, option);
        }

/** Sets the StatusMask
 */
        public void setStatusMask(long mask, char option) {
           myMetaData.setStatusMask(mask, option);
        }


/**
 * Sets the XML
 */
    public void setXML(String xml) throws XMLParseException {
        try {
            setNode(LocalXMLProvider.stringToNode(xml));
        }
        catch (Exception e) {
            throw new XMLParseException(e.getMessage());
        }
    }

    public boolean equals(Object obj) {
        LocalXMLResolver other = null;

        try {
            other = (LocalXMLResolver) obj;
            if (node == other.node)
                return true;
        }
        catch (Exception e) { }
        return false;
    }

}