Ajax response return undefined - php

Question

Hi I have been using ajax for many times. But I can't figure out whats the problem with my code this time. My head is blowing up since 2 days. I am using pusher for the realtime notification in CodeIgniter. Here's my code.
$(document).on("click", ".myonoffswitch", function () {
if (confirm("Sure!!! You want to Change the post status?"))
{
var thiss = $(this);
var prod_id = $(this).attr('id');
var status = $(this).attr('value');
var tdid = $(this).parent().prev().attr('class');
var td = $(this).parent().prev();
var adsstatus = $.ajax({type: "POST", dataType: "json", url: base_url + 'init/ads_status', data: {'prod_id': prod_id, 'status': status}});
$.when(adsstatus).done(function (adsstatuss) {
var msg;
msg = adsstatuss;
alert(msg.length);
var updated_status = msg[0].post_status;
alert(updated_status);
//alert(updated_status);
if (updated_status == "0" && tdid == prod_id) {
td.css("background", "#ccffcc");
td.text("On");
thiss.val(updated_status);
}
if (updated_status == "1" && tdid == prod_id) {
td.css("background", "#ffcccc");
td.text("Off");
thiss.val(updated_status);
}
});
}
});
ads_status (method in CodeIgniter)
public function ads_status() {
$prod_id = $_POST['prod_id'];
$status = $_POST['status'];
if ($status == "1") {
$new_status = "0";
$this->cmsdbmodel->ads_status($prod_id, $new_status);
$dat = $this->cmsdbmodel->get_updated_status($prod_id);
$ads_type = "product";
$emailreturn = $this->send_email_ads_status($prod_id, $ads_type);
//send user alert of product//
if ($dat[0]->post_status == "0") {
$lastInsertedId = $prod_id;
$modelNBrandId = $this->dbmodel->checkProductContainsAlert($lastInsertedId);
$getAlertEmail = $this->dbmodel->getAlertEmailFromBrandNModelId($modelNBrandId);
if (!empty($getAlertEmail)) {
foreach ($getAlertEmail as $alerts) {
$alertsEmail = $alerts->email;
}
}
$alertsPost = $this->dbmodel->getPostAlerts($lastInsertedId);
$sendPostAlerts = json_encode($alertsPost);
$encrytpEmail = hash('sha256', $alertsEmail);
$this->pusher->trigger($encrytpEmail, 'alerts', $sendPostAlerts);
}
//send user alert of product//
$realtime = $this->realTime_charts();
$realtime["post_status"] = $dat[0]->post_status;
$realtime["emailres"] = $emailreturn;
$data = $realtime;
$this->pusher->trigger('recent_activity', 'new_event1', $data);
echo json_encode($data);
}
}
Here I want to trigger event in pusher as well as echo json object. But in ajax, response is undefined. Also in console I can see json but when alerting the reponse it says undefined. Wheres problem in my code. Please help me.