use std::sync::{Arc, Mutex};
use std::task::{Context, Poll};

use anyhow::Result;
use boitalettres::server::accept::addr::AddrStream;
use boitalettres::errors::Error as BalError;
use boitalettres::proto::{Request, Response};
use futures::future::BoxFuture;
use imap_codec::types::command::CommandBody;
use tower::Service;

use crate::command;
use crate::login::Credentials;
use crate::mailstore::Mailstore;
use crate::mailbox::Mailbox;

pub struct Instance {
    pub mailstore: Arc<Mailstore>,
}
impl Instance {
    pub fn new(mailstore: Arc<Mailstore>) -> Self {
        Self { mailstore }
    }
}
impl<'a> Service<&'a AddrStream> for Instance {
    type Response = Connection;
    type Error = anyhow::Error;
    type Future = BoxFuture<'static, Result<Self::Response>>;

    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        Poll::Ready(Ok(()))
    }

    fn call(&mut self, addr: &'a AddrStream) -> Self::Future {
        tracing::info!(remote_addr = %addr.remote_addr, local_addr = %addr.local_addr, "accept");
        let ms = self.mailstore.clone();
        Box::pin(async { Ok(Connection::new(ms)) })
    }
}

pub struct Session {
    pub creds: Option<Credentials>,
    pub selected: Option<Mailbox>,
}

pub struct Connection {
    pub mailstore: Arc<Mailstore>,
    pub session: Arc<Mutex<Session>>,
}
impl Connection {
    pub fn new(mailstore: Arc<Mailstore>) -> Self {
        Self { mailstore, session: Arc::new(Mutex::new(Session { creds: None, selected: None, })) }
    }
}
impl Service<Request> for Connection {
    type Response = Response;
    type Error = BalError;
    type Future = BoxFuture<'static, Result<Self::Response, Self::Error>>;

    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        Poll::Ready(Ok(()))
    }

    fn call(&mut self, req: Request) -> Self::Future {
        tracing::debug!("Got request: {:#?}", req);
        let cmd = command::Command::new(req.tag, self.mailstore.clone(), self.session.clone());
        Box::pin(async move {
            match req.body {
                CommandBody::Capability => cmd.capability().await,
                CommandBody::Login { username, password } => cmd.login(username, password).await,
                CommandBody::Lsub { reference, mailbox_wildcard } => cmd.lsub(reference, mailbox_wildcard).await,
                CommandBody::List { reference, mailbox_wildcard } => cmd.list(reference, mailbox_wildcard).await,
                CommandBody::Select { mailbox } => cmd.select(mailbox).await,
                CommandBody::Fetch { sequence_set, attributes, uid } => cmd.fetch(sequence_set, attributes, uid).await,
               _ => Response::bad("Error in IMAP command received by server."),
            }
        })
    }
}