// js handling the login procedures

 

 // constants

 var NORMAL_STATE = 4;

 var LOGIN_PREFIX = 'login.php?';

 

 // variables

 var http = getHTTPObject(); // We create the HTTP Object

 var hasSeed = false;

 var loggedIn = false;

 var seed_id = 0;

 var seed = 0;

 var fullname = '';

 var messages = '';

 

 // getSeed method:  gets a seed from the server for this transaction

 function getSeed() 

 {		// only get a seed if we're not logged in and we don't already have one

 		if (!loggedIn && !hasSeed) {

 			// open up the path

 			http.open('GET', LOGIN_PREFIX + 'task=getseed', true);

 			http.onreadystatechange = handleHttpGetSeed;

 			http.send(null);

 		}

 }

 

 // handleHttpGetSeed method: called when the seed is returned from the server

 function handleHttpGetSeed()

 {

 	// if there hasn't been any errors

 	if (http.readyState == NORMAL_STATE) {

 		// split by the divider |

 		results = http.responseText.split('|');

 		

 		// id is the first element

 		seed_id = results[0];

 		

 		// seed is the second element

 		seed = results[1];

 		

 		// now we have the seed

 		hasSeed = true;

 	}

 }

 

 // validateLogin method: validates a login request

 function validateLogin()

 {

 	// ignore request if we are already logged in

 	if (loggedIn)

 		return;

 

 	// get form form elements 'username' and 'password'

 	username = document.getElementById('username').value;

 	password = document.getElementById('password').value;

 

 	// ignore if either is empty

 	if (username != '' && password  != '') {

 		// compute the hash of the hash of the password and the seed

 		hash = hex_md5(hex_md5(password) + seed);

 		

 		// open the http connection

 		http.open('GET', LOGIN_PREFIX + 'task=checklogin&username='+username+'&id='+seed_id+'&hash='+hash, true);

 		

 		// where to go

 		http.onreadystatechange = handleHttpValidateLogin;

 		http.send(null);

 	}

 }

 

 // handleHttpValidateLogin method: called when the validation results are returned from the server

 function handleHttpValidateLogin()

 {

 	// did the connection work?

 	if (http.readyState == NORMAL_STATE) {

 		// split by the pipe

 		results = http.responseText.split('|');

 		if (results[0] == 'true')

 		{

 			hasSeed = false;

 			loggedIn = true;

 			fullname = results[1];

 			messages = '';

 		}

 		else

 		{

 			messages = results[1];

 		}

 		showLogin();

 	}

 }

 

 // resetLogin method: if logged in, 'logs out' and allows a different user/pass to be entered

 function resetLogin()

 {

 	loggedIn = false;

 	hasSeed = false;

 }