package org.honours.greenstone;

import java.io.*;

import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.apache.log4j.Logger;
import org.expeditee.items.Text;
import org.greenstone.gsdl3.util.GSXML;
import org.greenstone.gsdl3.util.XMLConverter;
import org.w3c.dom.*;


public class ArchiveFileEditor {

	static Logger logger = Logger.getLogger(org.honours.greenstone.ArchiveFileEditor.class.getName());
	private XMLConverter _xmlConverter;
	private Document _document;
	private String _archiveDocFile;
	
	public ArchiveFileEditor(String docXML){
		_xmlConverter = new XMLConverter();
		_archiveDocFile = docXML;
		_document = _xmlConverter.getDOM(new File(_archiveDocFile));
	}
	
	public void editArchiveDocFile(Text text){
		try{
			String newText = text.getText();
			String data = (text.getData() != null) ? text.getData().get(0) : "";
			
			if(data.equals(""))
				return;
			
			
			NodeList nl = _document.getDocumentElement().getElementsByTagName("Description");
			Element description = (Element)nl.item(0);
			
			nl = description.getChildNodes();
			boolean found = false;
			for(int i = 0; i < nl.getLength(); i++){
				Node node = nl.item(i);
				
				if(node.getNodeType() == Node.ELEMENT_NODE){
					Element e = (Element)node;
					String originalText = e.getTextContent();
					
					if(e.getTagName().equals("Metadata") && e.getAttribute("name").equals(data)){
						
						if(!originalText.equals(newText)){
							GSXML.setNodeText(e, newText);
						}
						found = true;
					}
				}
			}
			
			if(!found){
				System.err.println("Create a new metadata");
				Element newElem = _document.createElement("Metadata");
				newElem.setAttribute("name",data);
				newElem.setTextContent(newText);
				description.appendChild(newElem);
				description.appendChild(_document.createTextNode("\n\t"));
				found = true;
			}
			
		}catch(Exception e){
			e.printStackTrace();
		}
	}
	
	/**
	 * Write out new stuff to doc.xml
	 */
	public void write(){
		
		try{
			TransformerFactory tf = TransformerFactory.newInstance();
			Transformer trans = tf.newTransformer();
			
			//generating string from xml tree.
			StringWriter sw = new StringWriter();
			StreamResult result = new StreamResult(sw);
			DOMSource source = new DOMSource(_document);
			
			trans.transform(source,result);
			String xmlString = sw.toString();
			
			//Saving XML content back to doc.xml file
			//System.err.println(_archiveDocFile);
			OutputStream os = new FileOutputStream(_archiveDocFile);
			byte[] buf = xmlString.getBytes();
			
			for(int i = 0; i < buf.length; i++)
				os.write(buf[i]);
			
			os.close();
			buf = null;
			
		}catch(Exception e){
			e.printStackTrace();
			return;
		}
	}
	
}