// mod to communicate with api-grub and preproc services
// using Unix-Socket Client

use anyhow::{Error, Result};
use integr_structs::api::ApiConfigV2;
use tokio::time::{sleep, Duration};
use tokio::net::UnixStream;
use std::env;
use tokio::sync::mpsc::Receiver;
use log::{info, error};
use serde_json::to_string_pretty;

#[derive(Debug)]
enum UnixSocketConsumer {
    ApiGrubber,
    Preproc,
}
// to create us-client
struct UnixSocketClient;  
// to catch new configs from integr submod
type ConfigGateway = Receiver<ApiConfigV2>;

pub async fn init_delivery_mech(rx: ConfigGateway) -> Result<()> {
    let mut rx = rx; 
    loop {
        while rx.is_empty() {
            continue;
        };
        info!("New config was pulled. Redirecting it ...");
        let config = rx.recv().await.unwrap();
        match UnixSocketConsumer::ApiGrubber.get_stream_object().await {
            Ok(socket) => {
                socket.try_write(to_string_pretty(&config)?.as_bytes())?;
                info!("New api config was pulled");
            },
            Err(er) => {
                error!("Cannot coonect to ApiGrubber Unix-Socket due to {er}");
            }
        }
        sleep(Duration::from_secs(3)).await;
    }
    // let api_sock = UnixSocketConsumer::ApiGrubber.get_stream_object().await?;
    // let preproc_sock = UnixSocketConsumer::Preproc.get_stream_object().await?;
}

impl UnixSocketConsumer {
    pub async fn get_stream_object(&self) -> Result<UnixStream> {
        let socket_file = match self {
            UnixSocketConsumer::ApiGrubber => env::var("API_GRUBBER_SOCKET")?,
            UnixSocketConsumer::Preproc => env::var("PREPROC_SOCKET")?,
        };
        UnixStream::connect(socket_file).await.or_else(|_| Err(Error::msg(format!("Cannot create {:?} Unix-Socket client", self))))
    } 
}

// async fn check_unix_socket_file(path: &str) -> bool {
//     std::path::Path::new(path).exists()
// }

#[cfg(test)]
mod delivery_unittests {
    #[allow(unused_imports)]
    use super::*;
    use tokio::test;

    // 
    #[test]
    async fn check_api_unix_socket_client_creation() { assert!(true); }
    
    #[test]
    async fn check_preproc_unix_socket_client_creation() { assert!(true); }
    // 
}