<%@ page language="java" import="java.security.*" %>
<%

	//! Tradetracker Redirect-Page.

	// Set domain name on which the redirect-page runs, WITHOUT "www.".
	String domainName = "";

	// Set the P3P compact policy.
	response.setHeader("P3P", "CP=\"ALL PUR DSP CUR ADMi DEVi CONi OUR COR IND\"");

	// Define parameters.
	String campaignID = "";
	String materialID = "";
	String affiliateID = "";
	String redirectURL = "";
	String reference = "";

	Boolean canRedirect = true;

	// Set parameters.
	if (request.getParameter("campaignID") != null)
	{
		campaignID = request.getParameter("campaignID");
		materialID = request.getParameter("materialID") == null ? "" : request.getParameter("materialID");
		affiliateID = request.getParameter("affiliateID") == null ? "" : request.getParameter("affiliateID");
		redirectURL = request.getParameter("redirectURL") == null ? "" : request.getParameter("redirectURL");
	}
	else if (request.getParameter("tt") != null)
	{
		String[] trackingData = request.getParameter("tt").split("_");

		campaignID = trackingData.length >= 1 ? trackingData[0] : "";
		materialID = trackingData.length >= 2 ? trackingData[1] : "";
		affiliateID = trackingData.length >= 3 ? trackingData[2] : "";
		reference = trackingData.length >= 4 ? trackingData[3] : "";

		redirectURL = request.getParameter("r") == null ? "" : request.getParameter("r");
	}
	else
		canRedirect = false;

	if (canRedirect)
	{
		// Calculate MD5 checksum.
		MessageDigest md = MessageDigest.getInstance("MD5");
		String MD5String = "CHK_" + campaignID + "::" + materialID + "::" + affiliateID + "::" + reference;

		byte[] ba_md5string = MD5String.getBytes();
		byte[] ba_md5string_encoded = md.digest(ba_md5string);

		StringBuffer sb = new StringBuffer();

		for (int i = 0; i < ba_md5string_encoded.length; ++i)
			sb.append(Integer.toHexString((ba_md5string_encoded[i] & 0xFF) | 0x100) . substring(1, 3));

		String MD5Checksum = sb.toString();

		// Calculate unix time stamp.
		long timeStamp = System.currentTimeMillis() / 1000;

		// Set session/cookie arguments.
		String cookieName = "TT2_" + campaignID;
		String cookieValue = materialID + "::" + affiliateID + "::" + reference + "::" + MD5Checksum + "::" + timeStamp;

		// Create tracking cookie.
		Cookie trackingCookie = new Cookie(cookieName, cookieValue);
		trackingCookie.setMaxAge(60 * 60 * 24 * 365);
		trackingCookie.setPath("/");

		if (domainName != "")
			trackingCookie.setDomain("." + domainName);

		response.addCookie(trackingCookie);

		// Set session data.
		session.setAttribute(cookieName, cookieValue);

		// Set track-back URL.
		String trackBackURL = "http://tc.tradetracker.net/?c=" + campaignID + "&m=" + materialID + "&a=" + affiliateID + "&r=" + java.net.URLEncoder.encode(reference) + "&u=" + java.net.URLEncoder.encode(redirectURL);

		// Redirect to TradeTracker.
		response.setStatus(301);
		response.setHeader("Location", trackBackURL);
	}

%>