/**
* display a message to the user before redirecting him to facebook
*/
protected function executeRedirectScreen()
{
$appId = $this->getFromConfig(FacebookConstants::FACEBOOK_APP_ID_REQUEST_PARAM);
$appSecret = $this->getFromConfig(FacebookConstants::FACEBOOK_APP_SECRET_REQUEST_PARAM);
$permissions = explode(',', base64_decode($this->getRequestParameter(FacebookConstants::FACEBOOK_PERMISSIONS_REQUEST_PARAM)));
$providerId = base64_decode($this->getRequestParameter(FacebookConstants::FACEBOOK_PROVIDER_ID_REQUEST_PARAM));
$requestPartnerId = base64_decode($this->getRequestParameter(FacebookConstants::FACEBOOK_PARTNER_ID_REQUEST_PARAM));
$ksStr = $this->getRequestParameter(FacebookConstants::FACEBOOK_KS_REQUEST_PARAM);
$this->ksError = null;
$this->partnerError = null;
$ksValid = $this->processKs($ksStr);
if (!$ksValid) {
$this->ksError = true;
return;
}
$ks = kCurrentContext::$ks_object;
$contextPartnerId = $ks->partner_id;
if (empty($requestPartnerId) || $contextPartnerId != $requestPartnerId) {
$this->partnerError = true;
return;
}
$ks = $this->generateTimeLimitedKs($contextPartnerId);
$params = $this->getForwardParameters();
$params[FacebookConstants::FACEBOOK_KS_REQUEST_PARAM] = $ks;
$params[FacebookConstants::FACEBOOK_NEXT_ACTION_REQUEST_PARAM] = base64_encode(self::SUB_ACTION_PROCESS_OAUTH2_RESPONSE);
$accessURL = $this->getFacebookDistributionAccessURL($providerId, $ks);
$dataHandler = new kDistributionPersistentDataHandler($accessURL);
$redirectUrl = $this->getController()->genUrl('extservices/facebookoauth2?' . http_build_query($params, null, '&'), true);
$reRequestPermissions = base64_decode($this->getRequestParameter(FacebookConstants::FACEBOOK_RE_REQUEST_PERMISSIONS_REQUEST_PARAM));
$this->oauth2Url = FacebookGraphSdkUtils::getLoginUrl($appId, $appSecret, $redirectUrl, $permissions, $dataHandler, $reRequestPermissions);
}
