/**
    * 
    */
   package de.tivsource.page.admin.security;
   
   
   import java.io.IOException;
   import java.util.List;
   import java.util.Map;
  
  import javax.naming.Context;
  import javax.naming.InitialContext;
  import javax.naming.NamingException;
  import javax.persistence.NoResultException;
  import javax.security.auth.Subject;
  import javax.security.auth.callback.Callback;
  import javax.security.auth.callback.CallbackHandler;
  import javax.security.auth.callback.NameCallback;
  import javax.security.auth.callback.PasswordCallback;
  import javax.security.auth.callback.UnsupportedCallbackException;
  import javax.security.auth.login.LoginException;
  import javax.security.auth.spi.LoginModule;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  
  import de.tivsource.page.dao.administration.UserDaoLocal;
  import de.tivsource.page.entity.administration.Role;
  import de.tivsource.page.entity.administration.User;
  import de.tivsource.page.valve.security.RemoteAddressThreadLocal;
  
  /**
   * @author Marc Michele
   *
   */
  public class AdminLoginModule implements LoginModule {
  
  	private static final Logger LOGGER = LogManager.getLogger("AuthLogger");
  	
  	private CallbackHandler handler;
  	private Subject subject;
  	private User userPrincipal;
  	private List<Role> rolePrincipals;
  	
  	@Override
  	public void initialize(Subject subject, CallbackHandler callbackHandler,
  			Map<String, ?> sharedState, Map<String, ?> options) {
  		handler = callbackHandler;
  		this.subject = subject;
  	}// Ende initialize()
  
  	@Override
  	public boolean login() throws LoginException {
  	    Callback[] callbacks = new Callback[2];
  	    callbacks[0] = new NameCallback("login");
  	    callbacks[1] = new PasswordCallback("password", true);
  
  
  	    try {
  	      handler.handle(callbacks);
  	      String name = ((NameCallback) callbacks[0]).getName();
  	      String password = String.valueOf(((PasswordCallback) callbacks[1]).getPassword());
  	      
  	      // Überprüfen ob der Name und
  	      // das Passwort gesetzt wurden
  	      if (name != null &&
  	          password != null) {
  
  	    	  Context initialContext = new InitialContext();
  	    	  UserDaoLocal userDaoLocal = (UserDaoLocal) initialContext.lookup("java:global/tiv-page/dao-0.0.1/UserDao");
  	    	  
  	    	  // Versuche benutzer mit dem Namen aus der Datenbank zu holen.
  	    	  User dbUser = userDaoLocal.findByUsername(name);
  
  	    	  
  	    	  // Überprüfen ob ein Benutzer gefunden wurde
  	    	  // und ob die Daten stimmen.
  	    	  if(dbUser != null &&
  	    	     name.equals(dbUser.getName()) && 
  	    	     password.equals(dbUser.getPassword())) {
  	    		  LOGGER.info("Login ok - "
  	    		  		+ "Auth-User: " + dbUser.getUsername()
  	    		  		+ " - "
  	    		  		+ "IP-Adresse: " + RemoteAddressThreadLocal.getKey()
  	    		  );
  	    		  userPrincipal = dbUser;
  	    		  return true;
  	    	  }// Ende if
  
  	      }// Ende if
  	      
  	      
  	      LOGGER.info("Login failed - "
  	      		+ "Auth-User: " + ((NameCallback) callbacks[0]).getName() + " - "
  	      		+ "Auth-Password: " + String.valueOf(((PasswordCallback) callbacks[1]).getPassword()) + " - "
  	      		+ "IP-Adresse: " + RemoteAddressThreadLocal.getKey()
  	      );
  
  	      // If credentials are NOT OK we throw a LoginException
 	      throw new LoginException("Authentication failed");
 	    } catch (UnsupportedCallbackException e) {
 		      LOGGER.info("Login failed - "
 			      		+ "Auth-User: " + ((NameCallback) callbacks[0]).getName() + " - "
 			      		+ "Auth-Password: " + String.valueOf(((PasswordCallback) callbacks[1]).getPassword()) + " - "
 			      		+ "IP-Adresse: " + RemoteAddressThreadLocal.getKey()
 		      );
 			throw new LoginException("Authentication failed (UnsupportedCallbackException)");			
 	    } catch (NamingException e) {
 		      LOGGER.info("Login failed - "
 			      		+ "Auth-User: " + ((NameCallback) callbacks[0]).getName() + " - "
 			      		+ "Auth-Password: " + String.valueOf(((PasswordCallback) callbacks[1]).getPassword()) + " - "
 			      		+ "IP-Adresse: " + RemoteAddressThreadLocal.getKey()
 		      );
 			throw new LoginException("Authentication failed (LoginException)");			
 		} catch (NoResultException e) {
 		      LOGGER.info("Login failed - "
 			      		+ "Auth-User: " + ((NameCallback) callbacks[0]).getName() + " - "
 			      		+ "Auth-Password: " + String.valueOf(((PasswordCallback) callbacks[1]).getPassword()) + " - "
 			      		+ "IP-Adresse: " + RemoteAddressThreadLocal.getKey()
 		      );
 			throw new LoginException("Authentication failed (NoResultException)");			
 		} catch (IOException e) {
 		      LOGGER.info("Login failed - "
 			      		+ "Auth-User: " + ((NameCallback) callbacks[0]).getName() + " - "
 			      		+ "Auth-Password: " + String.valueOf(((PasswordCallback) callbacks[1]).getPassword()) + " - "
 			      		+ "IP-Adresse: " + RemoteAddressThreadLocal.getKey()
 		      );
 			throw new LoginException("Authentication failed (IOException)");
 		}
 	}
 
 	@Override
 	public boolean commit() throws LoginException {
 	    subject.getPrincipals().add(userPrincipal);
 	    rolePrincipals = userPrincipal.getRoles();
 
 	    for (Role roleName : rolePrincipals) {
 	    	subject.getPrincipals().add(roleName);
 	    }
 	    return true;
 	}
 
 	@Override
 	public boolean abort() throws LoginException {
 		return false;
 	}
 
 	@Override
 	public boolean logout() throws LoginException {
 		subject.getPrincipals().remove(userPrincipal);
 	    subject.getPrincipals().remove(rolePrincipals);
 	    return true;
 	}
 
 }// Ende class