use std::sync::Arc;

use actix_web::{App, HttpRequest, HttpResponse, HttpServer, web};

use crate::engine::heartbeat::HeartbeatManager;
use crate::engine::packet::Packet;
use crate::engine::session::SessionStore;

#[derive(Debug, Clone)]
pub struct EngineConfig {
    pub ping_interval: u64,
    pub ping_timeout: u64,
    pub max_payload: usize,
    pub path: String,
}

impl Default for EngineConfig {
    fn default() -> Self {
        Self {
            ping_interval: 25000,
            ping_timeout: 20000,
            max_payload: 1_000_000,
            path: "/engine.io/".to_string(),
        }
    }
}

pub struct EngineServer {
    pub config: EngineConfig,
    pub store: SessionStore,
    on_message: Arc<dyn Fn(String, Packet) + Send + Sync>,
}

#[derive(Debug, serde::Deserialize)]
pub struct EngineQuery {
    #[serde(rename = "EIO")]
    pub eio: Option<String>,
    pub transport: Option<String>,
    pub sid: Option<String>,
}

pub async fn engine_get(
    req: HttpRequest,
    body: web::Payload,
    query: web::Query<EngineQuery>,
    store: web::Data<SessionStore>,
    config: web::Data<EngineConfig>,
    on_message: web::Data<Arc<dyn Fn(String, Packet) + Send + Sync>>,
) -> Result<HttpResponse, actix_web::Error> {
    match query.transport.as_deref() {
        Some("websocket") => {
            crate::engine::websocket::websocket_handler(
                req,
                body,
                web::Query(crate::engine::websocket::WsQuery {
                    eio: query.eio.clone(),
                    transport: query.transport.clone(),
                    sid: query.sid.clone(),
                }),
                store,
                config,
                on_message,
            )
            .await
        }
        _ => Ok(crate::engine::polling::polling_get(
            req,
            web::Query(crate::engine::polling::PollingQuery {
                eio: query.eio.clone(),
                transport: query.transport.clone(),
                sid: query.sid.clone(),
            }),
            store,
            config,
            on_message,
        )
        .await),
    }
}

impl EngineServer {
    pub fn new(
        config: EngineConfig,
        on_message: impl Fn(String, Packet) + Send + Sync + 'static,
    ) -> Self {
        Self {
            config,
            store: SessionStore::new(),
            on_message: Arc::new(on_message),
        }
    }

    pub fn with_store(
        config: EngineConfig,
        store: SessionStore,
        on_message: impl Fn(String, Packet) + Send + Sync + 'static,
    ) -> Self {
        Self {
            config,
            store,
            on_message: Arc::new(on_message),
        }
    }

    pub async fn run_http(self: Arc<Self>, addr: &str) -> std::io::Result<()> {
        let store = self.store.clone();
        let config = self.config.clone();
        let on_message = self.on_message.clone();

        // Start heartbeat manager to clean up stale sessions
        let heartbeat = Arc::new(HeartbeatManager::new(
            store.clone(),
            config.ping_interval,
            config.ping_timeout,
        ));
        let heartbeat_handle = heartbeat.start();

        tracing::info!("Engine.IO HTTP server listening on {}", addr);

        let result = HttpServer::new(move || {
            App::new()
                .app_data(web::Data::new(store.clone()))
                .app_data(web::Data::new(config.clone()))
                .app_data(web::Data::new(on_message.clone()))
                .route(
                    "/health",
                    web::get().to(crate::engine::health::health_check),
                )
                .route("/engine.io/", web::get().to(engine_get))
                .route(
                    "/engine.io/",
                    web::post().to(crate::engine::polling::polling_post),
                )
        })
        .bind(addr)?
        .run()
        .await;

        heartbeat_handle.abort();
        result
    }

    pub async fn run_webtransport(
        &self,
        port: u16,
        cert_path: &str,
        key_path: &str,
    ) -> crate::ImksResult<()> {
        crate::engine::webtransport::run_webtransport_server(
            port,
            cert_path,
            key_path,
            self.store.clone(),
            self.config.clone(),
            self.on_message.clone(),
        )
        .await
    }
}