package com.mattfleming;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.text.MessageFormat;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.axis.Message;
import org.apache.axis.MessageContext;
import org.apache.axis.client.AxisClient;
import org.apache.axis.configuration.NullProvider;
import org.apache.axis.utils.XMLUtils;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.methods.RequestEntity;
import org.apache.commons.httpclient.methods.StringRequestEntity;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.apache.ws.security.WSConstants;
import org.apache.ws.security.WSSConfig;
import org.apache.ws.security.components.crypto.Crypto;
import org.apache.ws.security.components.crypto.CryptoFactory;
import org.apache.ws.security.message.WSSignEnvelope;
import org.w3c.dom.Document;

/**
 * Prototype of a proxy class that signs an inbound SOAP message using legacy
 * (OASIS 2006) security headers.
 * 
 */
public class WSSecurityWrapperProxy extends javax.servlet.http.HttpServlet
		implements javax.servlet.Servlet {
	private static final long serialVersionUID = 1L;

	private static final Crypto crypto = CryptoFactory.getInstance();

	protected void doPost(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		response.setContentType("text/xml");
		// set the true destination of the SOAP request
		PostMethod httppost = new PostMethod("https://therealdestination.com");
		try {
			// setup the outbound message format
			AxisClient engine = new AxisClient(new NullProvider());
			MessageContext msgContext = new MessageContext(engine);
			WSSConfig config = WSSConfig.getNewInstance();
			config.setWsseNS(WSConstants.WSSE_NS_OASIS_2003_06);
			config.setWsuNS(WSConstants.WSU_NS_OASIS_2003_06);
			config.setBSTAttributesQualified(false);
			config.setBSTValuesPrefixed(true);
			WSSignEnvelope signer = new WSSignEnvelope(config, null, true);

			// setup the message signer
			String alias = "key_for_signing";
			String password = "key_for_signing_password";
			signer.setUserInfo(alias, password);
			signer.setKeyIdentifierType(WSConstants.BST_DIRECT_REFERENCE);

			// create an axis message from the posted contents
			Message axisMessage = new Message(request.getInputStream());
			axisMessage.setMessageContext(msgContext);
			Document signedDoc = signer.build(axisMessage.getSOAPEnvelope()
					.getAsDocument(), crypto);
			Writer sw = new StringWriter();
			XMLUtils.DocumentToWriter(signedDoc, sw);
			String signedString = sw.toString();

			// send the message to the real end point
			HttpClient httpclient = new HttpClient();
			// need to use corporate proxy
			httpclient.getHostConfiguration().setProxy(
					"draconian.proxy.company.com", 8080);

			RequestEntity ent = new StringRequestEntity(signedString);
			HttpMethodParams params = new HttpMethodParams();
			params.setSoTimeout(20000);
			httppost.setParams(params);
			httppost.setRequestEntity(ent);
			// must be set to be a SOAP request
			httppost.addRequestHeader("SOAPAction", "");
			httpclient.executeMethod(httppost);
			response.getWriter().print(httppost.getResponseBodyAsString());
		} catch (Exception e) {
			StringWriter sw = new StringWriter();
			e.printStackTrace(new PrintWriter(sw));
			response.getWriter().print(
					MessageFormat.format(ERROR_SOAP, new Object[] {
							e.getMessage(), sw.toString() }));
		} finally {
			httppost.releaseConnection();
		}
	}

	private static final String ERROR_SOAP = "<?xml version=\"1.0\" encoding=\"utf-8\"?><soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\"><soapenv:Body><soapenv:Fault><faultcode>soapenv:Client</faultcode><faultstring>{0}</faultstring>><detail><stackTrace>{1}</stackTrace></detail></soapenv:Fault></soapenv:Body></soapenv:Envelope>";

}