/**
* oAuth2 authorization. If the acess_token needs to be refreshed pass $refresh_token as first parameter,
* if this is the first time getting access_token from user, then set the first parameter to false, pass the auth code
* in the second.
* @param bool $refresh_token
* @param bool $auth_code
* @return array $tokens
*/
function authorize($refresh_token = FALSE, $auth_code = FALSE)
{
$auth = new Authorize($this->conn, $this->api_key, $this->api_secret);
$tokens = $refresh_token ? $auth->refreshAccessToken($refresh_token) : $auth->getAccessToken($auth_code);
!$tokens ? $auth->getAuthorizationCode() : $this->conn->setAccessData($tokens['access_token'], $tokens['refresh_token']);
return $tokens;
}