package it.bigatti.soap;

import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

import javax.xml.messaging.*;
import javax.xml.soap.*;

public class MathServlet extends JAXMServlet implements ReqRespListener {

	public void init(ServletConfig sc) throws ServletException {
		super.init(sc);
	}
	
	public SOAPMessage onMessage(SOAPMessage message) {
		SOAPMessage response = null;
		String values = null;
		
		try {
			message.writeTo( System.out );
			
			SOAPPart sp = message.getSOAPPart();
			SOAPEnvelope env = sp.getEnvelope();
			SOAPHeader hdr = env.getHeader();
			SOAPBody bdy = env.getBody();
			
			Iterator ii = bdy.getChildElements();
			while( ii.hasNext() ) {
				
				SOAPElement e = (SOAPElement)ii.next();
				Iterator kk = e.getChildElements();
				
				while( kk.hasNext() ) {
					
					SOAPElement ee = (SOAPElement)kk.next();
					String name = ee.getElementName().getLocalName();
					
					if( name != null && name.equals("values") ) {
						values = ee.getValue();
						System.out.println("values = " + values);
						break;
					}
					
				}
			}
			
			if( values != null ) {
				response = createResponse( new MathSupport( values ) );
				response.writeTo( System.out );
			}
			
		} catch(Exception e) {
			e.printStackTrace(); 
		}
		
		return response;
	}

    protected SOAPMessage createResponse( MathSupport ms ) throws SOAPException {
		MessageFactory mf = MessageFactory.newInstance();
		SOAPMessage msg = mf.createMessage();
		SOAPPart sp = msg.getSOAPPart();
		SOAPEnvelope env = sp.getEnvelope();
		SOAPHeader hdr = env.getHeader();
		SOAPBody bdy = env.getBody();
		
		String xsi = "http://www.w3.org/2001/XMLSchema-instance";
		env.addNamespaceDeclaration("xsi", xsi); 
		env.addNamespaceDeclaration("xsd", "http://www.w3.org/2001/XMLSchema");
		env.addNamespaceDeclaration("soapenc", "http://schemas.xmlsoap.org/soap/encoding/");
		env.setEncodingStyle("http://schemas.xmlsoap.org/soap/encoding/");
		Name xsiTypeString = env.createName("type", "xsi", xsi);
		
		SOAPBodyElement gltp = bdy.addBodyElement(
			env.createName("CalculateResponse", "ns1", "http://namespaces.bigatti.it")
		);
		
		SOAPElement e1 = gltp.addChildElement(
			env.createName("Summary")
		);

		SOAPElement e2 = e1.addChildElement(
			env.createName("Mean")
		).addTextNode("" + ms.getMean() );
		e2.addAttribute( xsiTypeString, "xsd:float" );

		e2 = e1.addChildElement(
			env.createName("StandardDeviation")
		).addTextNode("" + ms.getStandardDeviation() );
		e2.addAttribute( xsiTypeString, "xsd:float" );

		e2 = e1.addChildElement(
			env.createName("CoefficientOfVariation")
		).addTextNode("" + ms.getCoefficientOfVariation() );
		e2.addAttribute( xsiTypeString, "xsd:float" );

		e2 = e1.addChildElement(
			env.createName("Sum")
		).addTextNode("" + ms.getSum() );
		e2.addAttribute( xsiTypeString, "xsd:double" );

		e2 = e1.addChildElement(
			env.createName("Min")
		).addTextNode("" + ms.getMin() );
		e2.addAttribute( xsiTypeString, "xsd:float" );

		e2 = e1.addChildElement(
			env.createName("Max")
		).addTextNode("" + ms.getMax() );
		e2.addAttribute( xsiTypeString, "xsd:float" );
		
		e1 = gltp.addChildElement(
			env.createName("Values")
		);
		
		int counter = 0;
		Iterator valuesList = ms.getRecognizedValues();
		while( valuesList.hasNext() ) {
			String value = (String)valuesList.next();
			
			e2 = e1.addChildElement(
				env.createName("Value")
			).addTextNode("" + value );
			
			e2.addAttribute( env.createName("id"), "" + counter );
			e2.addAttribute( xsiTypeString, "xsd:float" );
			
			counter++;
		}
			
		return msg;
    }
	
	class MathSupport {
		List values = new LinkedList();
		double sum = 0;
		double squaredSum = 0;
		int counter = 0;
		float min;
		float max;

		public MathSupport( String valueString ) {
			
			StringTokenizer valueTokenizer = new StringTokenizer( valueString );
			while( valueTokenizer.hasMoreTokens() ) {
				try {
					String stringValue = valueTokenizer.nextToken();
					float value = Float.parseFloat( stringValue );
					
					values.add( stringValue );
					
					sum += value;
					squaredSum += value * value;
					
					min = ( value < min || counter == 0 ) ? value : min;
					max = ( value > max) ? value : max;
					
					counter++;
				} catch( NumberFormatException ex ) {
					//ignore errors
				}
			}
		}
		
		public float getCoefficientOfVariation() {
			return getStandardDeviation() / getMean();
		}
		
		public float getStandardDeviation() {
			float mean = getMean();
			return (float)( Math.sqrt( squaredSum - ( mean * mean ) / (counter-1) ) );
		}
		
		public float getMean() {
			return (float)(sum / counter);
		}
		
		public double getSum() {
			return sum;
		}
		
		public float getMin() {
			return min;
		}
		
		public float getMax() {
			return max;
		}
		
		public Iterator getRecognizedValues() {
			return values.iterator();
		}
	}
}