robert@0: // js handling the login procedures
robert@0: 
robert@0: // constants
robert@0: var NORMAL_STATE = 4;
robert@0: var LOGIN_PREFIX = 'login.php?';
robert@0: 
robert@0: // variables
robert@0: var http = getHTTPObject(); // We create the HTTP Object
robert@0: var hasSeed = false;
robert@0: var loggedIn = false;
robert@0: var seed_id = 0;
robert@0: var seed = 0;
robert@0: var fullname = '';
robert@0: var messages = '';
robert@0: 
robert@0: // getSeed method:  gets a seed from the server for this transaction
robert@0: function getSeed() 
robert@0: {		// only get a seed if we're not logged in and we don't already have one
robert@0: 		if (!loggedIn && !hasSeed) {
robert@0: 			// open up the path
robert@0: 			http.open('GET', LOGIN_PREFIX + 'task=getseed', true);
robert@0: 			http.onreadystatechange = handleHttpGetSeed;
robert@0: 			http.send(null);
robert@0: 		}
robert@0: }
robert@0: 
robert@0: // handleHttpGetSeed method: called when the seed is returned from the server
robert@0: function handleHttpGetSeed()
robert@0: {
robert@0: 	// if there hasn't been any errors
robert@0: 	if (http.readyState == NORMAL_STATE) {
robert@0: 		// split by the divider |
robert@0: 		results = http.responseText.split('|');
robert@0: 		
robert@0: 		// id is the first element
robert@0: 		seed_id = results[0];
robert@0: 		
robert@0: 		// seed is the second element
robert@0: 		seed = results[1];
robert@0: 		
robert@0: 		// now we have the seed
robert@0: 		hasSeed = true;
robert@0: 	}
robert@0: }
robert@0: 
robert@0: // validateLogin method: validates a login request
robert@0: function validateLogin()
robert@0: {
robert@0: 	// ignore request if we are already logged in
robert@0: 	if (loggedIn)
robert@0: 		return;
robert@0: 
robert@0: 	// get form form elements 'username' and 'password'
robert@0: 	username = document.getElementById('username').value;
robert@0: 	password = document.getElementById('password').value;
robert@0: 
robert@0: 	// ignore if either is empty
robert@0: 	if (username != '' && password  != '') {
robert@0: 		// compute the hash of the hash of the password and the seed
robert@0: 		hash = hex_md5(hex_md5(password) + seed);
robert@0: 		
robert@0: 		// open the http connection
robert@0: 		http.open('GET', LOGIN_PREFIX + 'task=checklogin&username='+username+'&id='+seed_id+'&hash='+hash, true);
robert@0: 		
robert@0: 		// where to go
robert@0: 		http.onreadystatechange = handleHttpValidateLogin;
robert@0: 		http.send(null);
robert@0: 	}
robert@0: }
robert@0: 
robert@0: // handleHttpValidateLogin method: called when the validation results are returned from the server
robert@0: function handleHttpValidateLogin()
robert@0: {
robert@0: 	// did the connection work?
robert@0: 	if (http.readyState == NORMAL_STATE) {
robert@0: 		// split by the pipe
robert@0: 		results = http.responseText.split('|');
robert@0: 		if (results[0] == 'true')
robert@0: 		{
robert@0: 			hasSeed = false;
robert@0: 			loggedIn = true;
robert@0: 			fullname = results[1];
robert@0: 			messages = '';
robert@0: 		}
robert@0: 		else
robert@0: 		{
robert@0: 			messages = results[1];
robert@0: 		}
robert@0: 		showLogin();
robert@0: 	}
robert@0: }
robert@0: 
robert@0: // resetLogin method: if logged in, 'logs out' and allows a different user/pass to be entered
robert@0: function resetLogin()
robert@0: {
robert@0: 	loggedIn = false;
robert@0: 	hasSeed = false;
robert@0: }