/**
 * @author Hyacinthe MENIET
 * Created on 25 août 07
 */
package net.dotmyself.restclient.yahoosearch;

import java.io.ByteArrayInputStream;
import java.util.List;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * Web services Client which calls the Yahoo! Term Extraction service.
 */
public class TermExtractionWSClient {

	/**
	 * The main method.
	 * @param args
	 * 	The block of text that the terms will be extracted from.
	 * @throws Exception 
	 */
	public static void main(String[] args) throws Exception {
		if(args == null || args.length < 1) {
			throw new IllegalArgumentException("You must indicate the text you want to extract important terms.");
		}
		// Reads and parse the given XML with DOM
		DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
		DocumentBuilder constructor = factory.newDocumentBuilder();
		ByteArrayInputStream str = new ByteArrayInputStream(args[0].getBytes("ISO-8859-1"));
		Document document = constructor.parse(str);
		Element root = document.getDocumentElement();
		String context = getTagValue("context",root);
		String query = getTagValue("query",root);
		// Displays results
		List<String> terms = TermExtractionMapper.getTerms(context, query);
		for(String term : terms) {
			System.out.println(term);
		}
	}
	/**
	 * Returns the text content of the given tag.
	 * @param tag
	 * 	The tag.
	 * @param root
	 * 	The root Element.
	 * @return
	 * 	The String or <code>null</code> if
     * 	no String could be found.
	 */
	private static String getTagValue(String tag, Element root) {
        NodeList listOfTags = root.getElementsByTagName(tag);
        if(listOfTags != null && listOfTags.getLength() > 0) {
	        Node node = listOfTags.item(0);
	        return node.getTextContent();
        }
        return null;
	}

}