use std::sync::Arc;

use crate::{control, event::EventManager, router::build_router};
use axum::extract::FromRef;
use plc_platform_core::{bootstrap, websocket::WebSocketManager};
use plc_platform_core::{
    config::ServerConfig, connection::ConnectionManager, platform_context::PlatformContext,
};
use tokio::sync::mpsc;

#[derive(Clone)]
pub struct AppState {
    pub config: ServerConfig,
    pub platform: PlatformContext,
    pub event_manager: Arc<EventManager>,
    pub control_runtime: Arc<control::runtime::ControlRuntimeStore>,
}

impl FromRef<AppState> for PlatformContext {
    fn from_ref(state: &AppState) -> Self {
        state.platform.clone()
    }
}

pub async fn run() {
    let Some(_single_instance) = bootstrap::init_process(
        "PLCControl.FeederDistributor",
        "Another feeder distributor instance is already running",
    ) else {
        return;
    };

    let config = ServerConfig::from_env("HOST", "0.0.0.0", "PORT", 60309)
        .expect("Failed to load server configuration");
    let builder = bootstrap::bootstrap_platform(&config.database_url)
        .await
        .expect("Failed to bootstrap platform");

    let control_runtime = Arc::new(control::runtime::ControlRuntimeStore::new());
    let platform = builder.build();

    let event_manager = Arc::new(EventManager::new(
        platform.pool.clone(),
        Some(platform.ws_manager.clone()),
        platform.metadata.clone(),
    ));

    bootstrap::connect_all_enabled_sources(&platform)
        .await
        .expect("Failed to connect enabled sources");

    let state = AppState {
        config: config.clone(),
        platform,
        event_manager,
        control_runtime: control_runtime.clone(),
    };
    control::engine::start(state.clone(), control_runtime);

    if control::simulate::enabled() {
        tracing::info!("SIMULATE_PLC enabled: starting chaos simulation");
        control::simulate::start(state.clone());
    }

    let app = build_router(state.clone());
    let ui_url = config.local_ui_url();
    let (shutdown_tx, shutdown_rx) = mpsc::channel::<()>(1);
    let rt_handle = tokio::runtime::Handle::current();
    init_tray(ui_url, shutdown_tx.clone(), rt_handle);

    let connection_manager_for_shutdown = state.platform.connection_manager.clone();
    bootstrap::install_ctrl_c_shutdown(shutdown_tx);

    bootstrap::serve_app_with_graceful_shutdown(
        &config,
        "feeder distributor",
        app,
        bootstrap::disconnect_all_on_shutdown(
            shutdown_rx,
            connection_manager_for_shutdown,
            "feeder",
        ),
    )
    .await
    .unwrap();
}

pub fn test_state() -> AppState {
    let database_url = "postgres://plc:plc@localhost/plc_control_test".to_string();
    let pool = sqlx::postgres::PgPoolOptions::new()
        .connect_lazy(&database_url)
        .expect("lazy pool should build");
    let connection_manager = Arc::new(ConnectionManager::new());
    let ws_manager = Arc::new(WebSocketManager::new());
    let platform = PlatformContext::new(pool.clone(), connection_manager, ws_manager.clone());
    let event_manager = Arc::new(EventManager::new(
        pool,
        Some(ws_manager),
        platform.metadata.clone(),
    ));

    AppState {
        config: ServerConfig {
            database_url,
            server_host: "127.0.0.1".to_string(),
            server_port: 0,
        },
        platform,
        event_manager,
        control_runtime: Arc::new(control::runtime::ControlRuntimeStore::new()),
    }
}

#[cfg(windows)]
fn init_tray(ui_url: String, shutdown_tx: mpsc::Sender<()>, rt_handle: tokio::runtime::Handle) {
    std::thread::spawn(move || {
        if let Err(err) = tray::run_tray(ui_url, shutdown_tx, rt_handle) {
            tracing::warn!("Tray init failed: {}", err);
        }
    });
}

#[cfg(not(windows))]
fn init_tray(_ui_url: String, _shutdown_tx: mpsc::Sender<()>, _rt_handle: tokio::runtime::Handle) {}

#[cfg(windows)]
mod tray {
    use std::error::Error;

    use tokio::sync::mpsc;
    use tray_icon::{
        menu::{Menu, MenuEvent, MenuItem},
        Icon, TrayIconBuilder,
    };
    use winit::application::ApplicationHandler;
    use winit::event_loop::{ActiveEventLoop, ControlFlow, EventLoop};
    use winit::platform::windows::EventLoopBuilderExtWindows;

    pub fn run_tray(
        ui_url: String,
        shutdown_tx: mpsc::Sender<()>,
        rt_handle: tokio::runtime::Handle,
    ) -> Result<(), Box<dyn Error>> {
        let mut builder = EventLoop::builder();
        builder.with_any_thread(true);
        let event_loop = builder.build()?;

        let menu = Menu::new();
        let open_item = MenuItem::new("Open UI", true, None);
        let exit_item = MenuItem::new("Exit", true, None);
        menu.append(&open_item)?;
        menu.append(&exit_item)?;

        let icon = Icon::from_rgba(vec![0, 120, 212, 255], 1, 1)?;
        let _tray = TrayIconBuilder::new()
            .with_tooltip("PLC Feeder Distributor")
            .with_menu(Box::new(menu))
            .with_icon(icon)
            .build()?;

        let menu_rx = MenuEvent::receiver();
        let mut app = TrayApp {
            menu_rx,
            open_id: open_item.id().clone(),
            exit_id: exit_item.id().clone(),
            ui_url,
            shutdown_tx,
            rt_handle,
        };

        event_loop.run_app(&mut app).map_err(|err| err.into())
    }

    struct TrayApp {
        menu_rx: &'static tray_icon::menu::MenuEventReceiver,
        open_id: tray_icon::menu::MenuId,
        exit_id: tray_icon::menu::MenuId,
        ui_url: String,
        shutdown_tx: mpsc::Sender<()>,
        rt_handle: tokio::runtime::Handle,
    }

    impl ApplicationHandler for TrayApp {
        fn resumed(&mut self, _event_loop: &ActiveEventLoop) {}

        fn window_event(
            &mut self,
            _event_loop: &ActiveEventLoop,
            _window_id: winit::window::WindowId,
            _event: winit::event::WindowEvent,
        ) {
        }

        fn about_to_wait(&mut self, event_loop: &ActiveEventLoop) {
            event_loop.set_control_flow(ControlFlow::Wait);
            while let Ok(menu_event) = self.menu_rx.try_recv() {
                if menu_event.id == self.open_id {
                    let _ = webbrowser::open(&self.ui_url);
                }
                if menu_event.id == self.exit_id {
                    let _ = self.rt_handle.block_on(self.shutdown_tx.send(()));
                    event_loop.exit();
                }
            }
        }
    }
}