/src/sk/ibm/sa/utils/LoginUtils.java

package sk.ibm.sa.utils;



import java.math.BigInteger;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

import java.util.regex.Matcher;

import java.util.regex.Pattern;



import javax.faces.context.FacesContext;

import javax.servlet.http.HttpSession;



public class LoginUtils {



	public static final Pattern VALID_EMAIL_ADDRESS_REGEX = Pattern.compile("^[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,6}$",

			Pattern.CASE_INSENSITIVE);



	public static final String NICK_NAME = "nickName";



	public static void setHttpSessionEmailAttribute(String nickName) {

		getHttpSession().setAttribute(NICK_NAME, nickName);

	}



	/**

	 * 

	 * @return String email if user is logged, otherwise return null

	 */

	public static String getHttpSessionEmailAttribute() {

		HttpSession httpSession = getHttpSession();

		if (httpSession == null) {

			return null;

		} else {

			return (String) httpSession.getAttribute(NICK_NAME);

		}

	}



	public static boolean isEmailValid(String email) {

		Matcher matcher = VALID_EMAIL_ADDRESS_REGEX.matcher(email);

		return matcher.find();

	}



	public static String hash(String s) {

		try {

			MessageDigest md = MessageDigest.getInstance("md5");

			md.reset();

			md.update(s.getBytes());

			byte[] digest = md.digest();

			BigInteger bigInt = new BigInteger(1, digest);

			return bigInt.toString(16);

		} catch (NoSuchAlgorithmException e) {

			e.printStackTrace();

			return null;

		}

	}



	public static HttpSession getHttpSession() {

		return (HttpSession) FacesContext.getCurrentInstance().getExternalContext().getSession(false);

	}



}