use tokio::net::UdpSocket;
use tokio::sync::RwLock;
use std::error::Error;
use std::net::SocketAddr;
use std::sync::Arc;
use std::time::Duration;
use dashmap::DashMap;
use tokio::task::AbortHandle;
use tokio::time::{sleep, Instant};
use crate::domain::client::Client;
use crate::domain::event::{Event, EventBus};
use crate::network::protocol::{UdpClientMessage, UdpServerMessage};

#[derive(Clone)]
pub struct UdpServer {
    event_bus: EventBus,
    socket: Arc<UdpSocket>,
    abort_handle: Option<AbortHandle>,
    clients: Arc<DashMap<SocketAddr, Client>>,
}

impl UdpServer {
    pub async fn new(event_bus: EventBus, addr: &str) -> Self {
        let socket = UdpSocket::bind(addr).await.unwrap();
        let addr = socket.local_addr().unwrap();
        println!("Socket UDP lié avec succès on {}", addr);

        Self {
            event_bus,
            socket: Arc::new(socket),
            abort_handle: None,
            clients: Arc::new(DashMap::new()),
        }
    }

    pub async fn start(&mut self) -> Result<(), Box<dyn Error>> {
        println!("Démarrage du serveur UDP...");
        let event_bus = self.event_bus.clone();
        let socket = self.socket.clone();
        let clients = self.clients.clone();

        let recv_task = tokio::spawn(async move {
            let mut buf = [0u8; 1500];
            loop {
                match socket.recv_from(&mut buf).await {
                    Ok((size, address)) => {
                        // Ajouter le client à la liste
                        // todo : solution vraiment pas idéal, il faudrait vraiment la repenser avec un système helo/bye
                        if !clients.contains_key(&address) {
                            let client = Client::new(address);
                            clients.insert(address, client);
                            println!("Nouveau client connecté: {}", address);
                        }else {
                            let mut client = clients.get_mut(&address).unwrap();
                            client.update_last_seen();
                        }

                        if let Ok(message) = UdpClientMessage::from_bytes(&buf[..size]) {
                            let event = Event::UdpIn { address, size, message };
                            event_bus.emit(event).await;
                        } else {
                            println!("Erreur lors du parsing du message de {}: {:?}", address, &buf[..size]);
                        }
                    }
                    Err(e) => {
                        match e.kind() {
                            std::io::ErrorKind::ConnectionReset |
                            std::io::ErrorKind::ConnectionAborted => {
                                // Silencieux pour les déconnexions normales
                                continue;
                            }
                            _ => {
                                println!("Erreur UDP: {}", e);
                                continue;
                            }
                        }
                    }
                }
            }
        });

        self.abort_handle = Some(recv_task.abort_handle());
        Ok(())
    }

    pub async fn send(&self, address: SocketAddr, message: UdpServerMessage) -> bool {
        let event_bus = self.event_bus.clone();
        match self.socket.send_to(&message.to_byte(), address).await {
            Ok(size) => {
                event_bus.emit(Event::UdpOut { address, size, message }).await;
                true
            }
            Err(e) => {
                println!("Erreur lors de l'envoi du message à {}: {}", address, e);
                // Optionnel : retirer le client si l'adresse est invalide
                self.remove_client(address).await;
                false
            }
        }
    }

    pub async fn group_send(&self, addr_list: Vec<SocketAddr>, message: UdpServerMessage) -> bool {
        if addr_list.is_empty() {
            return true;
        }

        let socket = self.socket.clone();
        let clients = self.clients.clone();

        let send_tasks: Vec<_> = addr_list.into_iter().map(|address| {
            let event_bus = self.event_bus.clone();
            let message_clone = message.clone();
            let socket_clone = socket.clone();
            let clients_clone = clients.clone();

            tokio::spawn(async move {
                match socket_clone.send_to(&message_clone.to_byte(), address).await {
                    Ok(size) => {
                        event_bus.emit(Event::UdpOut { address, size, message: message_clone }).await;
                        true
                    }
                    Err(e) => {
                        println!("Erreur lors de l'envoi du message à {}: {}", address, e);
                        // Optionnel : retirer le client si l'adresse est invalide
                        if clients_clone.contains_key(&address) {
                            clients_clone.remove(&address);
                            println!("Client {} retiré de la liste", address);
                        }
                        false
                    }
                }
            })
        }).collect();

        let mut all_success = true;
        for task in send_tasks {
            match task.await {
                Ok(success) => {
                    if !success {
                        all_success = false;
                    }
                }
                Err(_) => {
                    all_success = false;
                }
            }
        }

        all_success
    }

    pub async fn all_send(&self, message: UdpServerMessage) -> bool {
        let client_addresses = self.get_clients().await;
        self.group_send(client_addresses, message).await
    }

    pub async fn get_clients(&self) -> Vec<SocketAddr> {
        self.clients.iter()
            .map(|entry| *entry.key())
            .collect()
    }

    // Nouvelle méthode pour nettoyer les clients déconnectés
    async fn remove_client(&self, address: SocketAddr) {
        if self.clients.contains_key(&address){
            self.clients.remove(&address);
            println!("Client {} retiré de la liste", address);
        }else {
            println!("Client {} n'est pas dans la liste", address);
        }
    }

    // Méthode pour nettoyer les clients inactifs
    pub async fn cleanup_inactive_clients(&self) {
        let timeout = Duration::from_secs(10);
        let now = Instant::now();
        let mut to_remove = Vec::new();

        for entry in self.clients.iter() {
            let address = *entry.key();
            let client = entry.value();

            if now.duration_since(client.last_seen()) > timeout {
                to_remove.push(address);
            }
        }

        for address in &to_remove {
            println!("Suppression du client {}", address);
            self.clients.remove(address);
        }
    }
}