use std::sync::Arc;

use anyhow::Result;
use tokio::sync::{
    Mutex,
    mpsc::{Receiver, Sender},
};

use crate::{
    database::Database,
    model::{Mail, MailQuery},
};

struct MailProcessor {
    rx: Receiver<Mail>,
    tx: Sender<Mail>,
    db: Arc<Mutex<Database>>,
}

// TODO: Store first then forward. On complete forward remove from db, otherwise save db with the
// emails to send to.
impl MailProcessor {
    async fn run(&mut self) -> Result<()> {
        // TODO: Check againts self.rx.is_closed() instead to stop the program before consuming all
        // of the queue. Store the emails not yet processed and restore the queue upon startup.
        while let Some(mail) = self.rx.recv().await {
            // TODO: should this be replaced with a send to another actor to pipeline the work? Is
            // the complexity worth the speedup?
            match self.do_processing(mail).await {
                Ok(_) => todo!(),
                Err(_) => todo!(),
            }
        }

        Ok(())
    }

    async fn do_processing(&mut self, mail: Mail) -> Result<()> {
        let mut db_guard = self.db.lock().await;
        db_guard.execute(MailQuery::Insert(&mail))?;
        drop(db_guard);

        todo!();
    }
}

mod tests {
    // TODO: Think of a way to test
}