#![cfg_attr(coverage, allow(unused_imports))]

use anyhow::Result;
use std::sync::Arc;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::time::Duration;
use tokio::sync::{broadcast, mpsc};
use tokio_stream::{StreamExt, wrappers::BroadcastStream};
use tonic::{Request, transport::Channel};
use tracing::{debug, error, info, trace, warn};
use winit::{
    event::Event,
    event_loop::{ControlFlow, EventLoopBuilder},
    platform::wayland::EventLoopBuilderExtWayland,
};

use lesavka_common::lesavka::{
    AudioPacket, KeyboardReport, MonitorRequest, MouseReport, VideoPacket,
    relay_client::RelayClient,
};

#[cfg(not(coverage))]
use crate::output::video::{MonitorWindow, UnifiedMonitorWindow};
use crate::{
    app_support, handshake, input::camera::CameraCapture, input::inputs::InputAggregator,
    input::microphone::MicrophoneCapture, output::audio::AudioOut, paste,
};

pub struct LesavkaClientApp {
    aggregator: Option<InputAggregator>,
    server_addr: String,
    dev_mode: bool,
    headless: bool,
    kbd_tx: broadcast::Sender<KeyboardReport>,
    mou_tx: broadcast::Sender<MouseReport>,
    paste_rx: Option<mpsc::UnboundedReceiver<String>>,
}

impl LesavkaClientApp {
    pub fn new() -> Result<Self> {
        let dev_mode = std::env::var("LESAVKA_DEV_MODE").is_ok();
        let headless = std::env::var("LESAVKA_HEADLESS").is_ok();
        let capture_remote_boot = std::env::var("LESAVKA_CAPTURE_REMOTE")
            .map(|value| value != "0")
            .unwrap_or(true);
        let args = std::env::args().skip(1).collect::<Vec<_>>();
        let env_addr = std::env::var("LESAVKA_SERVER_ADDR").ok();
        let server_addr = app_support::resolve_server_addr(&args, env_addr.as_deref());

        let (kbd_tx, _) = broadcast::channel(1024);
        let (mou_tx, _) = broadcast::channel(4096);
        let (paste_tx, paste_rx) = mpsc::unbounded_channel();

        let agg = if headless {
            None
        } else {
            Some(InputAggregator::new_with_capture_mode(
                dev_mode,
                kbd_tx.clone(),
                mou_tx.clone(),
                Some(paste_tx),
                capture_remote_boot,
            ))
        };

        Ok(Self {
            aggregator: agg,
            server_addr,
            dev_mode,
            headless,
            kbd_tx,
            mou_tx,
            paste_rx: Some(paste_rx),
        })
    }

    #[cfg(coverage)]
    pub async fn run(&mut self) -> Result<()> {
        info!(server = %self.server_addr, "🚦 starting handshake");
        let _caps = handshake::negotiate(&self.server_addr).await;
        if self.headless {
            info!("🧪 headless mode: skipping HID input capture");
        } else {
            info!("🧪 coverage mode: skipping runtime stream wiring");
        }
        std::future::pending::<Result<()>>().await
    }

    #[cfg(not(coverage))]
    pub async fn run(&mut self) -> Result<()> {
        /*────────── handshake / feature-negotiation ───────────────*/
        info!(server = %self.server_addr, "🚦 starting handshake");
        let caps = handshake::negotiate(&self.server_addr).await;
        tracing::info!("🤝 server capabilities = {:?}", caps);
        let camera_cfg = app_support::camera_config_from_caps(&caps);

        /*────────── persistent gRPC channels ──────────*/
        let hid_ep = Channel::from_shared(self.server_addr.clone())?
            .tcp_nodelay(true)
            .concurrency_limit(4)
            .http2_keep_alive_interval(Duration::from_secs(15))
            .connect_lazy();

        let vid_ep = Channel::from_shared(self.server_addr.clone())?
            .initial_connection_window_size(4 << 20)
            .initial_stream_window_size(4 << 20)
            .tcp_nodelay(true)
            .connect_lazy();

        let mut agg_task = None;
        let mut kbd_loop = None;
        let mut mou_loop = None;
        let mut paste_task = None;
        let paste_rx = self.paste_rx.take();
        if !self.headless {
            /*────────── input aggregator task (grab after handshake) ─────────────*/
            let mut aggregator = self.aggregator.take().expect("InputAggregator present");
            info!("⌛ grabbing input devices…");
            aggregator.init()?; // grab devices now that handshake succeeded
            agg_task = Some(tokio::spawn(async move {
                let mut a = aggregator;
                a.run().await
            }));

            /*────────── HID streams (never return) ────────*/
            kbd_loop = Some(self.stream_loop_keyboard(hid_ep.clone()));
            mou_loop = Some(self.stream_loop_mouse(hid_ep.clone()));
            if let Some(rx) = paste_rx {
                paste_task = Some(Self::paste_loop(hid_ep.clone(), rx));
            }
        } else {
            info!("🧪 headless mode: skipping HID input capture");
        }

        /*───────── optional 300 s auto-exit in dev mode */
        let suicide = async {
            if self.dev_mode {
                tokio::time::sleep(Duration::from_secs(300)).await;
                warn!("💀 dev-mode timeout");
                std::process::exit(0);
            } else {
                std::future::pending::<()>().await
            }
        };

        if !self.headless {
            let view_mode = std::env::var("LESAVKA_VIEW_MODE")
                .unwrap_or_else(|_| "breakout".to_string())
                .to_ascii_lowercase();
            let unified_view = view_mode == "unified";
            let disable_video_render = std::env::var("LESAVKA_DISABLE_VIDEO_RENDER")
                .map(|value| value.trim() != "0")
                .unwrap_or(false);
            info!(
                "🪟 video layout selected: {}",
                if unified_view { "unified" } else { "breakout" }
            );

            if disable_video_render {
                info!("🪟 launcher preview active; skipping standalone client video windows");
            } else {
                /*────────── video rendering thread (winit) ────*/
                let video_queue = app_support::sanitize_video_queue(
                    std::env::var("LESAVKA_VIDEO_QUEUE")
                        .ok()
                        .and_then(|v| v.parse::<usize>().ok()),
                );
                let dump_video = std::env::var("LESAVKA_DUMP_VIDEO").is_ok();
                let (video_tx, mut video_rx) =
                    tokio::sync::mpsc::channel::<VideoPacket>(video_queue);

                std::thread::spawn(move || {
                    gtk::init().expect("GTK initialisation failed");
                    #[allow(deprecated)]
                    {
                        let el = EventLoopBuilder::<()>::new()
                            .with_any_thread(true)
                            .build()
                            .unwrap();
                        enum Renderer {
                            Unified(UnifiedMonitorWindow),
                            Breakout {
                                left: MonitorWindow,
                                right: MonitorWindow,
                            },
                        }
                        let renderer = if unified_view {
                            Renderer::Unified(
                                UnifiedMonitorWindow::new().expect("unified-window")
                            )
                        } else {
                            Renderer::Breakout {
                                left: MonitorWindow::new(0).expect("win0"),
                                right: MonitorWindow::new(1).expect("win1"),
                            }
                        };

                        let _ = el.run(move |_: Event<()>, elwt| {
                            elwt.set_control_flow(ControlFlow::WaitUntil(
                                std::time::Instant::now() + std::time::Duration::from_millis(16),
                            ));
                            static CNT: std::sync::atomic::AtomicU64 =
                                std::sync::atomic::AtomicU64::new(0);
                            while let Ok(pkt) = video_rx.try_recv() {
                                CNT.fetch_add(1, std::sync::atomic::Ordering::Relaxed);
                                if CNT.load(std::sync::atomic::Ordering::Relaxed) % 300 == 0 {
                                    debug!(
                                        "🎥 received {} video packets",
                                        CNT.load(std::sync::atomic::Ordering::Relaxed)
                                    );
                                }
                                if dump_video {
                                    static DUMP_CNT: std::sync::atomic::AtomicU32 =
                                        std::sync::atomic::AtomicU32::new(0);
                                    let n =
                                        DUMP_CNT.fetch_add(1, std::sync::atomic::Ordering::Relaxed);
                                    let eye = if pkt.id == 0 { "l" } else { "r" };
                                    let path = format!("/tmp/eye{eye}-cli-{n:05}.h264");
                                    std::fs::write(&path, &pkt.data).ok();
                                }
                                match &renderer {
                                    Renderer::Unified(window) => window.push_packet(pkt),
                                    Renderer::Breakout { left, right } => match pkt.id {
                                        0 => left.push_packet(pkt),
                                        1 => right.push_packet(pkt),
                                        _ => {}
                                    },
                                }
                            }
                        });
                    }
                });

                /*────────── start video gRPC pullers ──────────*/
                let ep_video = vid_ep.clone();
                tokio::spawn(Self::video_loop(ep_video, video_tx));
            }

            /*────────── audio renderer & puller ───────────*/
            let audio_out = AudioOut::new()?;
            let ep_audio = vid_ep.clone();

            tokio::spawn(Self::audio_loop(ep_audio, audio_out));
        } else {
            info!("🧪 headless mode: skipping video/audio renderers");
        }
        /*────────── camera & mic tasks (gated by caps) ───────────*/
        if caps.camera && std::env::var("LESAVKA_CAM_DISABLE").is_err() {
            if let Some(cfg) = camera_cfg {
                info!(
                    codec = ?cfg.codec,
                    width = cfg.width,
                    height = cfg.height,
                    fps = cfg.fps,
                    "📸 using camera settings from server"
                );
            }
            let cam = Arc::new(CameraCapture::new(
                std::env::var("LESAVKA_CAM_SOURCE").ok().as_deref(),
                camera_cfg,
            )?);
            tokio::spawn(Self::cam_loop(vid_ep.clone(), cam));
        }
        if caps.microphone && std::env::var("LESAVKA_MIC_DISABLE").is_err() {
            let mic = Arc::new(MicrophoneCapture::new()?);
            tokio::spawn(Self::voice_loop(vid_ep.clone(), mic)); // renamed
        }

        /*────────── central reactor ───────────────────*/
        if self.headless {
            tokio::select! {
                _ = suicide => { /* handled above */ },
            }
        } else {
            let kbd_loop = kbd_loop.expect("kbd_loop");
            let mou_loop = mou_loop.expect("mou_loop");
            let agg_task = agg_task.expect("agg_task");
            let paste_task = paste_task.expect("paste_task");
            tokio::select! {
                _ = kbd_loop  => { warn!("⚠️⌨️ keyboard stream finished"); },
                _ = mou_loop  => { warn!("⚠️🖱️ mouse stream finished"); },
                _ = paste_task => { warn!("⚠️📋 paste loop finished"); },
                _ = suicide   => { /* handled above */ },
                r = agg_task  => {
                    match r {
                        Ok(Ok(()))        => warn!("input aggregator terminated cleanly"),
                        Ok(Err(e))        => error!("input aggregator error: {e:?}"),
                        Err(join_err)     => error!("aggregator task panicked: {join_err:?}"),
                    }
                    return Ok(());
                }
            }
        }

        // The branches above either loop forever or exit the process; this
        // point is unreachable but satisfies the type checker.
        #[allow(unreachable_code)]
        Ok(())
    }

    /*──────────────── paste loop ───────────────*/
    #[cfg(not(coverage))]
    fn paste_loop(
        ep: Channel,
        mut rx: mpsc::UnboundedReceiver<String>,
    ) -> tokio::task::JoinHandle<()> {
        tokio::spawn(async move {
            let mut cli = RelayClient::new(ep.clone());
            while let Some(text) = rx.recv().await {
                match paste::build_paste_request(&text) {
                    Ok(req) => match cli.paste_text(Request::new(req)).await {
                        Ok(resp) => {
                            let reply = resp.get_ref();
                            if !reply.ok {
                                warn!("📋 paste rejected: {}", reply.error);
                            } else {
                                debug!("📋 paste delivered");
                            }
                        }
                        Err(e) => {
                            warn!("📋 paste failed: {e}");
                            cli = RelayClient::new(ep.clone());
                        }
                    },
                    Err(e) => {
                        warn!("📋 paste build failed: {e}");
                    }
                }
            }
        })
    }

    /*──────────────── keyboard stream ───────────────*/
    #[cfg(not(coverage))]
    async fn stream_loop_keyboard(&self, ep: Channel) {
        loop {
            info!("⌨️🤙 Keyboard dial {}", self.server_addr);
            let mut cli = RelayClient::new(ep.clone());

            let outbound = BroadcastStream::new(self.kbd_tx.subscribe()).filter_map(|r| r.ok());

            match cli.stream_keyboard(Request::new(outbound)).await {
                Ok(mut resp) => {
                    while let Some(msg) = resp.get_mut().message().await.transpose() {
                        if let Err(e) = msg {
                            warn!("⌨️ server err: {e}");
                            break;
                        }
                    }
                }
                Err(e) => warn!("❌⌨️ connect failed: {e}"),
            }
            tokio::time::sleep(Duration::from_secs(1)).await; // retry
        }
    }

    /*──────────────── mouse stream ──────────────────*/
    #[cfg(not(coverage))]
    async fn stream_loop_mouse(&self, ep: Channel) {
        loop {
            info!("🖱️🤙 Mouse dial {}", self.server_addr);
            let mut cli = RelayClient::new(ep.clone());

            let outbound = BroadcastStream::new(self.mou_tx.subscribe()).filter_map(|r| r.ok());

            match cli.stream_mouse(Request::new(outbound)).await {
                Ok(mut resp) => {
                    while let Some(msg) = resp.get_mut().message().await.transpose() {
                        if let Err(e) = msg {
                            warn!("🖱️ server err: {e}");
                            break;
                        }
                    }
                }
                Err(e) => warn!("❌🖱️ connect failed: {e}"),
            }
            tokio::time::sleep(Duration::from_secs(1)).await;
        }
    }

    /*──────────────── monitor stream ────────────────*/
    #[cfg(not(coverage))]
    async fn video_loop(ep: Channel, tx: tokio::sync::mpsc::Sender<VideoPacket>) {
        let max_bitrate = std::env::var("LESAVKA_VIDEO_MAX_KBIT")
            .ok()
            .and_then(|v| v.parse::<u32>().ok())
            .unwrap_or(6_000);
        for monitor_id in 0..=1 {
            let ep = ep.clone();
            let tx = tx.clone();
            tokio::spawn(async move {
                loop {
                    let mut cli = RelayClient::new(ep.clone());
                    let req = MonitorRequest {
                        id: monitor_id,
                        max_bitrate,
                    };
                    match cli.capture_video(Request::new(req)).await {
                        Ok(mut stream) => {
                            debug!("🎥🏁 cli video{monitor_id}: stream opened");
                            while let Some(res) = stream.get_mut().message().await.transpose() {
                                match res {
                                    Ok(pkt) => {
                                        trace!(
                                            "🎥📥 cli video{monitor_id}: got {} bytes",
                                            pkt.data.len()
                                        );
                                        if tx.send(pkt).await.is_err() {
                                            warn!("⚠️🎥 cli video{monitor_id}: GUI thread gone");
                                            break;
                                        }
                                    }
                                    Err(e) => {
                                        error!("❌🎥 cli video{monitor_id}: gRPC error: {e}");
                                        break;
                                    }
                                }
                            }
                            warn!("⚠️🎥 cli video{monitor_id}: stream ended");
                        }
                        Err(e) => error!("❌🎥 video {monitor_id}: {e}"),
                    }
                    tokio::time::sleep(Duration::from_secs(1)).await;
                }
            });
        }
    }

    /*──────────────── audio stream ───────────────*/
    #[cfg(not(coverage))]
    async fn audio_loop(ep: Channel, out: AudioOut) {
        loop {
            let mut cli = RelayClient::new(ep.clone());
            let req = MonitorRequest {
                id: 0,
                max_bitrate: 0,
            };
            match cli.capture_audio(Request::new(req)).await {
                Ok(mut stream) => {
                    while let Some(res) = stream.get_mut().message().await.transpose() {
                        if let Ok(pkt) = res {
                            out.push(pkt);
                        }
                    }
                }
                Err(e) => tracing::warn!("❌🔊 audio stream err: {e}"),
            }
            tokio::time::sleep(Duration::from_secs(1)).await;
        }
    }

    /*──────────────── mic stream ─────────────────*/
    #[cfg(not(coverage))]
    async fn voice_loop(ep: Channel, mic: Arc<MicrophoneCapture>) {
        let mut delay = Duration::from_secs(1);
        static FAIL_CNT: AtomicUsize = AtomicUsize::new(0);
        loop {
            let mut cli = RelayClient::new(ep.clone());

            // 1. create a Tokio MPSC channel
            let (tx, rx) = tokio::sync::mpsc::channel::<AudioPacket>(256);
            let (stop_tx, stop_rx) = std::sync::mpsc::channel::<()>();

            // 2. spawn a real thread that does the blocking `pull()`
            let mic_clone = mic.clone();
            std::thread::spawn(move || {
                while stop_rx.try_recv().is_err() {
                    if let Some(pkt) = mic_clone.pull() {
                        trace!("🎤📤 cli  {} bytes → gRPC", pkt.data.len());
                        let _ = tx.blocking_send(pkt);
                    }
                }
            });

            // 3. turn `rx` into an async stream for gRPC
            let outbound = tokio_stream::wrappers::ReceiverStream::new(rx);
            match cli.stream_microphone(Request::new(outbound)).await {
                Ok(mut resp) => while resp.get_mut().message().await.transpose().is_some() {},
                Err(e) => {
                    // first failure → warn, subsequent ones → debug
                    if FAIL_CNT.fetch_add(1, Ordering::Relaxed) == 0 {
                        warn!("❌🎤 connect failed: {e}");
                        warn!("⚠️🎤 further microphone‑stream failures will be logged at DEBUG");
                    } else {
                        debug!("❌🎤 reconnect failed: {e}");
                    }
                    delay = app_support::next_delay(delay);
                }
            }
            let _ = stop_tx.send(());
            tokio::time::sleep(delay).await;
        }
    }

    /*──────────────── cam stream ───────────────────*/
    #[cfg(not(coverage))]
    async fn cam_loop(ep: Channel, cam: Arc<CameraCapture>) {
        let mut delay = Duration::from_secs(1);
        loop {
            let mut cli = RelayClient::new(ep.clone());
            let (tx, rx) = tokio::sync::mpsc::channel::<VideoPacket>(256);
            let (stop_tx, stop_rx) = std::sync::mpsc::channel::<()>();
            let cam_worker = std::thread::spawn({
                let cam = cam.clone();
                move || loop {
                    if stop_rx.try_recv().is_ok() {
                        break;
                    }
                    let Some(pkt) = cam.pull() else {
                        std::thread::sleep(Duration::from_millis(5));
                        continue;
                    };
                    // TRACE every 120 frames only
                    static CNT: std::sync::atomic::AtomicU64 = std::sync::atomic::AtomicU64::new(0);
                    let n = CNT.fetch_add(1, std::sync::atomic::Ordering::Relaxed);
                    if n < 10 || n % 120 == 0 {
                        tracing::trace!("📸 cli  frame#{n}  {} B", pkt.data.len());
                    }
                    tracing::trace!("📸⬆️ sent webcam AU pts={} {} B", pkt.pts, pkt.data.len());
                    if tx.blocking_send(pkt).is_err() {
                        break;
                    }
                }
            });

            let outbound = tokio_stream::wrappers::ReceiverStream::new(rx);
            match cli.stream_camera(Request::new(outbound)).await {
                Ok(mut resp) => {
                    delay = Duration::from_secs(1); // got a stream → reset
                    while resp.get_mut().message().await.transpose().is_some() {}
                }
                Err(e) if e.code() == tonic::Code::Unimplemented => {
                    tracing::warn!("📸 server does not support StreamCamera – giving up");
                    let _ = stop_tx.send(());
                    let _ = cam_worker.join();
                    return; // stop the task completely  (#3)
                }
                Err(e) => {
                    tracing::warn!("❌📸 connect failed: {e:?}");
                    delay = app_support::next_delay(delay); // back-off      (#2)
                }
            }
            let _ = stop_tx.send(());
            let _ = cam_worker.join();
            tokio::time::sleep(delay).await;
        }
    }
}