/**
* Pre-filter actions any submission, or prepares the form.
*
* @param T_Response $response encapsulated response to filter
*/
protected function doPreFilter(T_Response $response)
{
$t_field = $this->form->getAlias() . '_timeout';
$l_field = $this->form->getAlias() . '_thread_lock';
$s_field = $this->form->getAlias() . '_salt';
// prepare form:
// (a) add thread lock if required
// (b) add timeout
$timeout = new T_Form_Hidden($t_field, $this->timeout + time());
$this->form->addChild($timeout);
if ($this->lock_to) {
$lock_to = new T_Form_Hidden($l_field, $this->lock_to);
$this->form->addChild($lock_to);
}
// process form if is POST:
if ($this->env->isMethod('POST')) {
try {
// create salt field and validate to get salt
$salt = new T_Form_Hidden($s_field, null);
if ($salt->isSubmitted($this->env->input('POST'))) {
$salt->validate($this->env->input('POST'));
}
// salt form and validate
if ($salt->isPresent() && $salt->isValid()) {
$salt = $salt->getValue();
$this->form->setFieldnameSalt($salt, $this->hash);
if ($this->form->isSubmitted($this->env->input('POST'))) {
$this->form->validate($this->env->input('POST'));
}
}
// check timeout and thread lock
if ($this->form->isPresent() && $this->form->isValid()) {
// check timeout
$timeout = $this->form->search($t_field)->getValue();
if ($timeout < time()) {
$msg = 'This form has expired. Please submit the form ' . 'again to complete your request.';
throw new T_Exception_Filter($msg);
}
// check lock thread
if ($this->lock_to) {
$lock_to = $this->form->search($l_field)->getValue();
if (strcmp($lock_to, $this->lock_to) !== 0) {
$msg = 'A technical error occurred at our end, sorry. ' . 'Please submit the form again.';
throw new T_Exception_Filter($msg);
}
}
}
} catch (T_Exception_Filter $e) {
$this->form->setError(new T_Form_Error($e->getMessage()));
}
}
// ready form for redisplay (remember an error may be added in the POST
// method so make even a valid form ready for display).
// (a) Set form forward as same page
// (b) Salt form and add salt hidden input
// (c) Reset timeout from now
$this->form->setForward($this->env->getRequestUrl()->setParameters($this->env->input('GET')->uncage()));
$salt = uniqid(rand(), true);
$this->form->setFieldnameSalt($salt, $this->hash);
$this->form->addChild(new T_Form_Hidden($s_field, $salt));
// note that the salt hidden input is added *after* the form is
// salted as this input needs to be plain.
$this->form->search($t_field)->setValue($this->timeout + time());
}