pub mod asset_status;
pub mod backfill;
pub mod websocket;

use super::{clock, guard::Guard};
use crate::{
    config::{
        Config, ALPACA_CRYPTO_WEBSOCKET_URL, ALPACA_NEWS_WEBSOCKET_URL, ALPACA_STOCK_WEBSOCKET_URL,
    },
    types::{Class, Subset},
    utils::authenticate,
};
use futures_util::StreamExt;
use std::sync::Arc;
use tokio::{
    join, select, spawn,
    sync::{mpsc, Mutex, RwLock},
};
use tokio_tungstenite::connect_async;

#[derive(Clone, Copy, Debug)]
pub enum ThreadType {
    Bars(Class),
    News,
}

pub async fn run(
    app_config: Arc<Config>,
    mut asset_receiver: mpsc::Receiver<asset_status::Message>,
    mut clock_receiver: mpsc::Receiver<clock::Message>,
) {
    let (bars_us_equity_asset_status_sender, bars_us_equity_backfill_sender) =
        init_thread(app_config.clone(), ThreadType::Bars(Class::UsEquity)).await;
    let (bars_crypto_asset_status_sender, bars_crypto_backfill_sender) =
        init_thread(app_config.clone(), ThreadType::Bars(Class::Crypto)).await;
    let (news_asset_status_sender, news_backfill_sender) =
        init_thread(app_config.clone(), ThreadType::News).await;

    loop {
        select! {
            Some(asset_message) = asset_receiver.recv() => {
                spawn(handle_asset_message(
                    bars_us_equity_asset_status_sender.clone(),
                    bars_crypto_asset_status_sender.clone(),
                    news_asset_status_sender.clone(),
                    asset_message,
                ));
            }
            Some(_) = clock_receiver.recv() => {
                spawn(handle_clock_message(
                    bars_us_equity_backfill_sender.clone(),
                    bars_crypto_backfill_sender.clone(),
                    news_backfill_sender.clone(),
                ));
            }
            else => {
                panic!("Communication channel unexpectedly closed.")
            }
        }
    }
}

async fn init_thread(
    app_config: Arc<Config>,
    thread_type: ThreadType,
) -> (
    mpsc::Sender<asset_status::Message>,
    mpsc::Sender<backfill::Message>,
) {
    let guard = Arc::new(RwLock::new(Guard::new()));

    let websocket_url = match thread_type {
        ThreadType::Bars(Class::UsEquity) => format!(
            "{}/{}",
            ALPACA_STOCK_WEBSOCKET_URL, &app_config.alpaca_source
        ),
        ThreadType::Bars(Class::Crypto) => ALPACA_CRYPTO_WEBSOCKET_URL.into(),
        ThreadType::News => ALPACA_NEWS_WEBSOCKET_URL.into(),
    };

    let (websocket, _) = connect_async(websocket_url).await.unwrap();
    let (mut websocket_sender, mut websocket_receiver) = websocket.split();
    authenticate(&app_config, &mut websocket_sender, &mut websocket_receiver).await;
    let websocket_sender = Arc::new(Mutex::new(websocket_sender));

    let (asset_status_sender, asset_status_receiver) = mpsc::channel(100);
    spawn(asset_status::run(
        app_config.clone(),
        thread_type,
        guard.clone(),
        asset_status_receiver,
        websocket_sender.clone(),
    ));

    let (backfill_sender, backfill_receiver) = mpsc::channel(100);
    spawn(backfill::run(
        app_config.clone(),
        thread_type,
        guard.clone(),
        backfill_receiver,
    ));

    spawn(websocket::run(
        app_config.clone(),
        thread_type,
        guard.clone(),
        websocket_sender,
        websocket_receiver,
        backfill_sender.clone(),
    ));

    (asset_status_sender, backfill_sender)
}

async fn handle_asset_message(
    bars_us_equity_asset_status_sender: mpsc::Sender<asset_status::Message>,
    bars_crypto_asset_status_sender: mpsc::Sender<asset_status::Message>,
    news_asset_status_sender: mpsc::Sender<asset_status::Message>,
    asset_status_message: asset_status::Message,
) {
    let (us_equity_assets, crypto_assets): (Vec<_>, Vec<_>) = asset_status_message
        .assets
        .clone()
        .into_iter()
        .partition(|asset| asset.class == Class::UsEquity);

    let bars_us_equity_future = async {
        if !us_equity_assets.is_empty() {
            let (bars_us_equity_asset_status_message, bars_us_equity_asset_status_receiver) =
                asset_status::Message::new(asset_status_message.action.clone(), us_equity_assets);
            bars_us_equity_asset_status_sender
                .send(bars_us_equity_asset_status_message)
                .await
                .unwrap();
            bars_us_equity_asset_status_receiver.await.unwrap();
        }
    };

    let bars_crypto_future = async {
        if !crypto_assets.is_empty() {
            let (crypto_asset_status_message, crypto_asset_status_receiver) =
                asset_status::Message::new(asset_status_message.action.clone(), crypto_assets);
            bars_crypto_asset_status_sender
                .send(crypto_asset_status_message)
                .await
                .unwrap();
            crypto_asset_status_receiver.await.unwrap();
        }
    };

    let news_future = async {
        if !asset_status_message.assets.is_empty() {
            let (news_asset_status_message, news_asset_status_receiver) =
                asset_status::Message::new(
                    asset_status_message.action.clone(),
                    asset_status_message.assets,
                );
            news_asset_status_sender
                .send(news_asset_status_message)
                .await
                .unwrap();
            news_asset_status_receiver.await.unwrap();
        }
    };

    join!(bars_us_equity_future, bars_crypto_future, news_future);
    asset_status_message.response.send(()).unwrap();
}

async fn handle_clock_message(
    bars_us_equity_backfill_sender: mpsc::Sender<backfill::Message>,
    bars_crypto_backfill_sender: mpsc::Sender<backfill::Message>,
    news_backfill_sender: mpsc::Sender<backfill::Message>,
) {
    let bars_us_equity_future = async {
        let (bars_us_equity_backfill_message, bars_us_equity_backfill_receiver) =
            backfill::Message::new(backfill::Action::Backfill, Subset::All);
        bars_us_equity_backfill_sender
            .send(bars_us_equity_backfill_message)
            .await
            .unwrap();
        bars_us_equity_backfill_receiver.await.unwrap();
    };

    let bars_crypto_future = async {
        let (bars_crypto_backfill_message, bars_crypto_backfill_receiver) =
            backfill::Message::new(backfill::Action::Backfill, Subset::All);
        bars_crypto_backfill_sender
            .send(bars_crypto_backfill_message)
            .await
            .unwrap();
        bars_crypto_backfill_receiver.await.unwrap();
    };

    let news_future = async {
        let (news_backfill_message, news_backfill_receiver) =
            backfill::Message::new(backfill::Action::Backfill, Subset::All);
        news_backfill_sender
            .send(news_backfill_message)
            .await
            .unwrap();
        news_backfill_receiver.await.unwrap();
    };

    join!(bars_us_equity_future, bars_crypto_future, news_future);
}