use std::sync::Arc;

use anyhow::{bail, Result};
use futures::{try_join, StreamExt};
use log::*;
use rusoto_signature::Region;
use tokio::sync::watch;

use crate::config::*;
use crate::lmtp::*;
use crate::login::{ldap_provider::*, static_provider::*, *};
use crate::mailbox::Mailbox;

pub struct Server {
    pub login_provider: Arc<dyn LoginProvider + Send + Sync>,
    pub lmtp_server: Option<Arc<LmtpServer>>,
}

impl Server {
    pub fn new(config: Config) -> Result<Self> {
        let s3_region = Region::Custom {
            name: config.aws_region.clone(),
            endpoint: config.s3_endpoint,
        };
        let k2v_region = Region::Custom {
            name: config.aws_region,
            endpoint: config.k2v_endpoint,
        };
        let login_provider: Arc<dyn LoginProvider + Send + Sync> =
            match (config.login_static, config.login_ldap) {
                (Some(st), None) => Arc::new(StaticLoginProvider::new(st, k2v_region, s3_region)?),
                (None, Some(ld)) => Arc::new(LdapLoginProvider::new(ld, k2v_region, s3_region)?),
                (Some(_), Some(_)) => {
                    bail!("A single login provider must be set up in config file")
                }
                (None, None) => bail!("No login provider is set up in config file"),
            };

        let lmtp_server = config
            .lmtp
            .map(|cfg| LmtpServer::new(cfg, login_provider.clone()));

        Ok(Self {
            login_provider,
            lmtp_server,
        })
    }

    pub async fn run(&self) -> Result<()> {
        let (exit_signal, provoke_exit) = watch_ctrl_c();
        let exit_on_err = move |err: anyhow::Error| {
            error!("Error: {}", err);
            let _ = provoke_exit.send(true);
        };

        try_join!(async {
            match self.lmtp_server.as_ref() {
                None => Ok(()),
                Some(s) => s.run(exit_signal.clone()).await,
            }
        })?;
        Ok(())
    }

    pub async fn test(&self) -> Result<()> {
        let creds = self.login_provider.login("lx", "plop").await?;

        let mut mailbox = Mailbox::new(&creds, "TestMailbox".to_string()).await?;

        mailbox.test().await?;

        Ok(())
    }
}

pub fn watch_ctrl_c() -> (watch::Receiver<bool>, Arc<watch::Sender<bool>>) {
    let (send_cancel, watch_cancel) = watch::channel(false);
    let send_cancel = Arc::new(send_cancel);
    let send_cancel_2 = send_cancel.clone();
    tokio::spawn(async move {
        tokio::signal::ctrl_c()
            .await
            .expect("failed to install CTRL+C signal handler");
        info!("Received CTRL+C, shutting down.");
        send_cancel.send(true).unwrap();
    });
    (watch_cancel, send_cancel_2)
}