function getResponse()
{
global $RESPONSE, $SESSION;
if (!isset($_POST['sessionID'])) {
$RESPONSE = 'missing session ID';
return;
}
try {
$SESSION = Session::fromSessionID($_POST['sessionID']);
} catch (DoesNotExistException $e) {
$RESPONSE = 'invalid session ID';
return;
}
switch ($SESSION->getStatus()) {
case Session::awaiting_user_input:
processInput();
break;
case Session::group_request_pending:
// assuming a request is pending in the queue, has it expired?
if ($request = GroupRequestQueue::retrieveRequest($SESSION)) {
if ($request->expired()) {
// okay, we're done with this request
// delete it from the database
GroupRequestQueue::deleteRequests(array($request));
// $RESPONSE = 'no partner found! exiting. (TODO: exit trail)'; //TODO: exit trail
$SESSION->startExitTrail();
startStep();
return;
}
}
// nothing to do, except wait, because if a suitable partner comes along, the request pending status will be changed
$RESPONSE = array('action' => 'wait');
// TODO: countdown?
break;
case Session::group_request_fulfilled:
startStep();
break;
case Session::finished_step:
if (readyToMoveOn()) {
executeGroupCallbacks();
advanceStep();
} else {
/*
* readyToMoveOn sets the RESPONSE to the HTML of the waiting file.
* But because their status was already finished_step,
* we can assume that the waiting screen has already been loaded.
* So we just tell them to wait (overriding the response).
*/
// $RESPONSE = array('action' => 'wait');
}
break;
case Session::callback_done:
advanceStep();
break;
case Session::finished:
case Session::terminated:
$RESPONSE = 'session ended';
break;
default:
throw new Exception('unknown session status');
break;
}
}
