use rumqtt;
use rumqtt::LastWill;
use rumqtt::MqttClient;
use rumqtt::Notification;
use rumqtt::Receiver;
use rumqtt::{ConnectionMethod, MqttOptions, QoS, ReconnectOptions};

pub struct Mqtt {
    pub client: MqttClient,
    pub notifications: Receiver<Notification>,
}

impl Mqtt {
    pub fn connect(host: &str, port: u16) -> Result<Self, String> {
        let last_will = LastWill {
            topic: format!("{}/status", crate::MQTT_ID),
            message: "disconnected".to_string(),
            qos: QoS::AtLeastOnce,
            retain: true,
        };
        let options = MqttOptions::new(crate::MQTT_ID, host, port);
        let options = options
            .set_connection_method(ConnectionMethod::Tcp)
            .set_keep_alive(10)
            .set_last_will(last_will)
            .set_reconnect_opts(ReconnectOptions::Always(20));

        match MqttClient::start(options) {
            Ok((mut client, notifications)) => {
                match client.publish(
                    format!("{}/status", crate::MQTT_ID),
                    QoS::AtLeastOnce,
                    true,
                    "connected",
                ) {
                    Ok(()) => Ok(Mqtt {
                        client,
                        notifications,
                    }),
                    Err(conn_err) => Err(conn_err.to_string()),
                }
            }
            Err(conn_err) => Err(conn_err.to_string()),
        }
    }
}