use crate::bus::{Response, RequestEnvelope};
use async_std::sync::{Arc, Mutex};
use std::fmt::{Formatter, Debug, Error};
use futures::Stream;

#[async_trait]
pub trait BusConnection: Send + Stream<Item=RequestEnvelope> + Unpin {
    async fn close(&mut self);
    async fn ack(&mut self, id: u64);
    async fn send(&mut self, id: u64, message: Response);
}

#[derive(Clone)]
pub struct Receiver(Arc<Mutex<Box<dyn RawReceiver>>>, String);

impl Debug for Receiver {
    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> {
        write!(f, "Receiver {{ {} }}", self.1)
    }
}

impl Receiver {
    pub fn new(receiver: Box<dyn RawReceiver>) -> Receiver {
        let name = receiver.name();
        Receiver(Arc::new(Mutex::new(receiver)), name.to_string())
    }

    pub async fn get(&mut self) -> Option<Box<dyn BusConnection>> {
        self.0.lock().await.get().await
    }
}

#[async_trait]
pub trait RawReceiver: Send {
    fn name<'s>(&self) -> &'s str;
    async fn disconnect(&mut self);
    async fn get(&mut self) -> Option<Box<dyn BusConnection>>;
}