// client/src/app.rs
#![forbid(unsafe_code)]
use anyhow::Result;
use std::time::Duration;
use tokio::{sync::broadcast, task::JoinHandle};
use tokio_stream::{wrappers::BroadcastStream, StreamExt};
use tonic::Request;
use tracing::{info, warn, error, debug};

use navka_common::navka::{relay_client::RelayClient, HidReport};
use crate::input::inputs::InputAggregator;

pub struct NavkaClientApp {
    aggregator: Option<InputAggregator>,
    server_addr: String,
    dev_mode: bool,
    tx: broadcast::Sender<HidReport>,
}

impl NavkaClientApp {
    pub fn new() -> Result<Self> {
        info!("Creating navka-client app!");
        let dev_mode = std::env::var("NAVKA_DEV_MODE").is_ok();
        let addr = std::env::args()
            .nth(1)
            .or_else(|| std::env::var("NAVKA_SERVER_ADDR").ok())
            .unwrap_or_else(|| "http://127.0.0.1:50051".to_owned());

        let (tx, _) = broadcast::channel::<HidReport>(2048);   // 🖱️ + ⌨️ burst‑proof
        let mut aggregator = InputAggregator::new(dev_mode, tx.clone());
        aggregator.init()?;   // discover & grab

        Ok(Self {
            aggregator: Some(aggregator),
            server_addr: addr,
            dev_mode,
            tx,
        })
    }

    pub async fn run(&mut self) -> Result<()> {
        info!("Running navka-client app!");
        // spawn aggregator
        let mut aggregator = std::mem::take(&mut self.aggregator).expect("aggregator must exist");
        let aggregator_task: JoinHandle<Result<()>> = tokio::spawn(async move {
            aggregator.run().await
        });

        // dev-mode kill future
        let suicide_future = async {
            if self.dev_mode {
                info!("DEV-mode: will kill itself in 30s");
                tokio::time::sleep(Duration::from_secs(30)).await;
                Err::<(), _>(anyhow::anyhow!("dev-mode timer expired - goodbye cruel world..."))
            } else {
                futures::future::pending().await
            }
        };

        // Combine aggregator + dev + reconnect logic
        tokio::select! {
            // aggregator finishes
            agg_res = aggregator_task => {
                match agg_res {
                    Ok(Ok(())) => {
                        error!("Aggregator ended normally, exiting.");
                        std::process::exit(0);
                    }
                    Ok(Err(e)) => {
                        error!("Aggregator ended with error: {e}");
                        std::process::exit(1);
                    }
                    Err(join_err) => {
                        error!("Aggregator task panicked or was cancelled: {join_err}");
                        std::process::exit(1);
                    }
                }
            },
            // dev-mode
            res = suicide_future => {
                warn!("Dev-mode: {res:?}");
                std::process::exit(0);
            },
            // reconnect loop
            _ = self.reconnect_loop() => {
                warn!("Reconnect loop ended??");
                std::process::exit(0);
            }
        }
    }

    /// The loop that dials the server, sets up gRPC streaming,
    /// and waits for inbound to end. Then tries again, unless aggregator ended.
    async fn reconnect_loop(&self) {
        loop {
            // dial the servers
            info!("📞 dialling {}", self.server_addr);
            let mut client = match RelayClient::connect(self.server_addr.clone()).await {
                Ok(c) => c,
                Err(e) => {
                    error!("connect error {e}, sleeping 1s");
                    tokio::time::sleep(Duration::from_secs(1)).await;
                    continue;
                }
            };

            // fresh reader over the *same* broadcast channel
            let outbound = BroadcastStream::new(self.tx.subscribe()).filter_map(|r| r.ok());

            info!("🛫 spawning stream()");
            let response = match client.stream(Request::new(outbound)).await {
                Ok(r) => { info!("✅ stream established"); r },
                Err(e) => {
                    error!("stream RPC error: {e}, sleeping 1s");
                    tokio::time::sleep(Duration::from_secs(1)).await;
                    continue;
                }
            };

            let mut inbound = response.into_inner();
            while let Some(res) = inbound.message().await.transpose() {
                match res {
                    Ok(report) => {
                        debug!(?report.kind, "↩️  echo from server");
                    },
                    Err(e) => {
                        error!("Inbound error: {e}");
                        break;
                    }
                }
            }
            warn!("🔌 disconnected – retrying in 1 s");
            tokio::time::sleep(Duration::from_secs(1)).await;
        }
    }
}