//! Network service for Synor.

use crate::behaviour::SynorBehaviour;
use crate::config::NetworkConfig;
use crate::message::{BlockAnnouncement, TransactionAnnouncement};
use crate::peer::{Direction, PeerInfo, PeerManager, reputation};
use crate::protocol::{SynorRequest, SynorResponse};
use crate::rate_limit::{PerPeerLimiter, RateLimitConfig as TokenBucketConfig};
use crate::ratelimit::{RateLimitResult, RateLimiters};
use crate::reputation::{ReputationManager, ViolationType};
use crate::sync::{SyncManager, SyncStatus};
use crate::topics;
use futures::StreamExt;
use libp2p::{
    gossipsub,
    identify,
    kad,
    mdns,
    ping,
    request_response,
    swarm::SwarmEvent,
    Multiaddr, PeerId, Swarm, SwarmBuilder,
};
use parking_lot::RwLock;
use std::sync::Arc;
use synor_types::{Block, BlockHeader, Hash256};
use thiserror::Error;
use tokio::sync::{broadcast, mpsc, oneshot};
use tracing::{debug, info, trace, warn};

/// Network events.
#[derive(Clone, Debug)]
pub enum NetworkEvent {
    /// New block received from network.
    NewBlock(BlockAnnouncement),
    /// New transaction received from network.
    NewTransaction(TransactionAnnouncement),
    /// Peer connected.
    PeerConnected(PeerId),
    /// Peer disconnected.
    PeerDisconnected(PeerId),
    /// Sync status changed.
    SyncStatusChanged(SyncStatus),
    /// Request blocks from peer.
    BlocksReceived(Vec<Block>),
    /// Headers received.
    HeadersReceived(Vec<BlockHeader>),
}

/// Commands to the network service.
pub enum NetworkCommand {
    /// Dial a peer.
    Dial(Multiaddr),
    /// Disconnect a peer.
    Disconnect(PeerId),
    /// Ban a peer.
    Ban(PeerId),
    /// Unban a peer.
    Unban(PeerId),
    /// Broadcast a block.
    BroadcastBlock(BlockAnnouncement),
    /// Broadcast a transaction.
    BroadcastTransaction(TransactionAnnouncement),
    /// Request blocks from a peer.
    RequestBlocks {
        peer: PeerId,
        block_ids: Vec<synor_types::BlockId>,
        response: oneshot::Sender<Result<Vec<Block>, NetworkError>>,
    },
    /// Request headers from a peer.
    RequestHeaders {
        peer: PeerId,
        start: synor_types::BlockId,
        max_count: u32,
        response: oneshot::Sender<Result<Vec<BlockHeader>, NetworkError>>,
    },
    /// Get peer count.
    GetPeerCount(oneshot::Sender<usize>),
    /// Get sync status.
    GetSyncStatus(oneshot::Sender<SyncStatus>),
    /// Start sync.
    StartSync,
    /// Stop the service.
    Shutdown,
}

/// Handle for interacting with the network service.
#[derive(Clone)]
pub struct NetworkHandle {
    command_tx: mpsc::Sender<NetworkCommand>,
    event_rx: broadcast::Sender<NetworkEvent>,
}

impl NetworkHandle {
    /// Dials a peer at the given address.
    pub async fn dial(&self, addr: Multiaddr) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::Dial(addr))
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }

    /// Disconnects a peer.
    pub async fn disconnect(&self, peer_id: PeerId) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::Disconnect(peer_id))
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }

    /// Bans a peer.
    pub async fn ban(&self, peer_id: PeerId) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::Ban(peer_id))
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }

    /// Unbans a peer.
    pub async fn unban(&self, peer_id: PeerId) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::Unban(peer_id))
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }

    /// Broadcasts a block to the network.
    pub async fn broadcast_block(&self, announcement: BlockAnnouncement) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::BroadcastBlock(announcement))
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }

    /// Broadcasts a transaction to the network.
    pub async fn broadcast_transaction(&self, announcement: TransactionAnnouncement) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::BroadcastTransaction(announcement))
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }

    /// Requests blocks from a peer.
    pub async fn request_blocks(
        &self,
        peer: PeerId,
        block_ids: Vec<synor_types::BlockId>,
    ) -> Result<Vec<Block>, NetworkError> {
        let (tx, rx) = oneshot::channel();
        self.command_tx
            .send(NetworkCommand::RequestBlocks {
                peer,
                block_ids,
                response: tx,
            })
            .await
            .map_err(|_| NetworkError::ServiceStopped)?;
        rx.await.map_err(|_| NetworkError::ServiceStopped)?
    }

    /// Requests headers from a peer.
    pub async fn request_headers(
        &self,
        peer: PeerId,
        start: synor_types::BlockId,
        max_count: u32,
    ) -> Result<Vec<BlockHeader>, NetworkError> {
        let (tx, rx) = oneshot::channel();
        self.command_tx
            .send(NetworkCommand::RequestHeaders {
                peer,
                start,
                max_count,
                response: tx,
            })
            .await
            .map_err(|_| NetworkError::ServiceStopped)?;
        rx.await.map_err(|_| NetworkError::ServiceStopped)?
    }

    /// Gets the current peer count.
    pub async fn peer_count(&self) -> Result<usize, NetworkError> {
        let (tx, rx) = oneshot::channel();
        self.command_tx
            .send(NetworkCommand::GetPeerCount(tx))
            .await
            .map_err(|_| NetworkError::ServiceStopped)?;
        rx.await.map_err(|_| NetworkError::ServiceStopped)
    }

    /// Gets the current sync status.
    pub async fn sync_status(&self) -> Result<SyncStatus, NetworkError> {
        let (tx, rx) = oneshot::channel();
        self.command_tx
            .send(NetworkCommand::GetSyncStatus(tx))
            .await
            .map_err(|_| NetworkError::ServiceStopped)?;
        rx.await.map_err(|_| NetworkError::ServiceStopped)
    }

    /// Starts synchronization.
    pub async fn start_sync(&self) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::StartSync)
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }

    /// Subscribes to network events.
    pub fn subscribe(&self) -> broadcast::Receiver<NetworkEvent> {
        self.event_rx.subscribe()
    }

    /// Shuts down the network service.
    pub async fn shutdown(&self) -> Result<(), NetworkError> {
        self.command_tx
            .send(NetworkCommand::Shutdown)
            .await
            .map_err(|_| NetworkError::ServiceStopped)
    }
}

/// Network service errors.
#[derive(Debug, Error)]
pub enum NetworkError {
    #[error("Service has stopped")]
    ServiceStopped,

    #[error("Transport error: {0}")]
    Transport(String),

    #[error("Dial error: {0}")]
    DialError(String),

    #[error("Request timeout")]
    Timeout,

    #[error("Request failed: {0}")]
    RequestFailed(String),

    #[error("Peer not found")]
    PeerNotFound,

    #[error("Invalid response")]
    InvalidResponse,

    #[error("Serialization error: {0}")]
    Serialization(String),

    #[error("Rate limited: retry after {0} seconds")]
    RateLimited(u64),

    #[error("Peer in cooldown: wait {0} seconds")]
    PeerCooldown(u64),

    #[error("Peer is banned")]
    PeerBanned,
}

/// The network service.
pub struct NetworkService {
    /// The libp2p swarm.
    swarm: Swarm<SynorBehaviour>,
    /// Peer manager.
    peer_manager: Arc<PeerManager>,
    /// Sync manager.
    sync_manager: Arc<SyncManager>,
    /// Reputation manager for peer banning.
    reputation_manager: Arc<ReputationManager>,
    /// Rate limiters for DoS protection (sliding window).
    rate_limiters: RateLimiters,
    /// Token bucket rate limiter for incoming messages.
    token_bucket_limiter: PerPeerLimiter,
    /// Configuration.
    config: NetworkConfig,
    /// Command receiver.
    command_rx: mpsc::Receiver<NetworkCommand>,
    /// Event sender.
    event_tx: broadcast::Sender<NetworkEvent>,
    /// Pending requests.
    pending_requests: RwLock<std::collections::HashMap<
        request_response::OutboundRequestId,
        PendingRequest,
    >>,
}

struct PendingRequest {
    response_tx: Option<oneshot::Sender<Result<SynorResponse, NetworkError>>>,
}

impl NetworkService {
    /// Creates a new network service.
    pub async fn new(config: NetworkConfig) -> Result<(Self, NetworkHandle), Box<dyn std::error::Error>> {
        // Generate keypair
        let local_keypair = libp2p::identity::Keypair::generate_ed25519();
        let local_peer_id = PeerId::from(local_keypair.public());

        info!("Local peer ID: {}", local_peer_id);

        // Build swarm
        let swarm = SwarmBuilder::with_existing_identity(local_keypair)
            .with_tokio()
            .with_tcp(
                libp2p::tcp::Config::default(),
                libp2p::noise::Config::new,
                libp2p::yamux::Config::default,
            )?
            .with_quic()
            .with_dns()?
            .with_behaviour(|key| {
                SynorBehaviour::new(key, &config).expect("Behaviour creation failed")
            })?
            .with_swarm_config(|cfg| {
                cfg.with_idle_connection_timeout(config.idle_timeout)
            })
            .build();

        // Create peer, sync, and reputation managers
        let peer_manager = Arc::new(PeerManager::new(config.max_inbound, config.max_outbound));
        let sync_manager = Arc::new(SyncManager::new(
            config.sync.clone(),
            Arc::clone(&peer_manager),
            Hash256::from_bytes([0u8; 32]), // Will be set properly when genesis is known
        ));
        let reputation_manager = Arc::new(ReputationManager::new());

        // Create channels
        let (command_tx, command_rx) = mpsc::channel(256);
        let (event_tx, _) = broadcast::channel(1024);

        let handle = NetworkHandle {
            command_tx,
            event_rx: event_tx.clone(),
        };

        // Create token bucket limiter with default config: 100 req/s, burst of 200
        let token_bucket_config = TokenBucketConfig::default();
        let token_bucket_limiter = PerPeerLimiter::new(token_bucket_config);

        let service = NetworkService {
            swarm,
            peer_manager,
            sync_manager,
            reputation_manager,
            rate_limiters: RateLimiters::default(),
            token_bucket_limiter,
            config,
            command_rx,
            event_tx,
            pending_requests: RwLock::new(std::collections::HashMap::new()),
        };

        Ok((service, handle))
    }

    /// Starts the network service.
    pub async fn run(mut self) -> Result<(), Box<dyn std::error::Error>> {
        // Listen on configured addresses
        for addr in &self.config.listen_addresses {
            match self.swarm.listen_on(addr.clone()) {
                Ok(_) => info!("Listening on {}", addr),
                Err(e) => warn!("Failed to listen on {}: {}", addr, e),
            }
        }

        // Subscribe to topics
        if let Err(e) = self.swarm.behaviour_mut().subscribe_topics() {
            warn!("Failed to subscribe to topics: {}", e);
        }

        // Connect to bootstrap peers
        for addr in &self.config.bootstrap_peers {
            if let Err(e) = self.swarm.dial(addr.clone()) {
                warn!("Failed to dial bootstrap peer {}: {}", addr, e);
            }
        }

        // Main event loop
        loop {
            tokio::select! {
                // Handle swarm events
                event = self.swarm.select_next_some() => {
                    self.handle_swarm_event(event).await;
                }

                // Handle commands
                Some(cmd) = self.command_rx.recv() => {
                    if !self.handle_command(cmd).await {
                        break;
                    }
                }
            }
        }

        info!("Network service shutting down");
        Ok(())
    }

    /// Handles a swarm event.
    async fn handle_swarm_event(&mut self, event: SwarmEvent<crate::behaviour::SynorBehaviourEvent>) {
        match event {
            SwarmEvent::NewListenAddr { address, .. } => {
                info!("Listening on {}", address);
            }

            SwarmEvent::ConnectionEstablished { peer_id, endpoint, .. } => {
                // Check if peer is banned via reputation system
                if self.reputation_manager.is_banned(&peer_id) {
                    warn!("Rejecting connection from banned peer: {}", peer_id);
                    let _ = self.swarm.disconnect_peer_id(peer_id);
                    return;
                }

                let direction = if endpoint.is_dialer() {
                    Direction::Outbound
                } else {
                    Direction::Inbound
                };

                let addr = endpoint.get_remote_address().clone();
                let info = if direction == Direction::Inbound {
                    PeerInfo::new_inbound(peer_id)
                } else {
                    PeerInfo::new_outbound(peer_id, addr.clone())
                };

                if self.peer_manager.add_peer(peer_id, info) {
                    info!("Connected to peer: {} ({:?})", peer_id, direction);
                    self.swarm.behaviour_mut().add_address(&peer_id, addr);
                    let _ = self.event_tx.send(NetworkEvent::PeerConnected(peer_id));
                }
            }

            SwarmEvent::ConnectionClosed { peer_id, .. } => {
                self.peer_manager.remove_peer(&peer_id);
                // Clean up rate limiter state for disconnected peer
                self.rate_limiters.reset(&peer_id);
                self.token_bucket_limiter.reset_peer(&peer_id);
                info!("Disconnected from peer: {}", peer_id);
                let _ = self.event_tx.send(NetworkEvent::PeerDisconnected(peer_id));
            }

            SwarmEvent::Behaviour(behaviour_event) => {
                self.handle_behaviour_event(behaviour_event).await;
            }

            _ => {}
        }
    }

    /// Handles a behaviour event.
    async fn handle_behaviour_event(&mut self, event: crate::behaviour::SynorBehaviourEvent) {
        use crate::behaviour::SynorBehaviourEvent;

        match event {
            SynorBehaviourEvent::Gossipsub(gossipsub::Event::Message {
                propagation_source,
                message_id: _,
                message,
            }) => {
                self.handle_gossip_message(propagation_source, message).await;
            }

            SynorBehaviourEvent::RequestResponse(request_response::Event::Message {
                peer,
                message,
            }) => {
                match message {
                    request_response::Message::Request { request, channel, .. } => {
                        self.handle_request(peer, request, channel).await;
                    }
                    request_response::Message::Response { request_id, response } => {
                        self.handle_response(peer, request_id, response).await;
                    }
                }
            }

            SynorBehaviourEvent::RequestResponse(request_response::Event::OutboundFailure {
                peer,
                request_id,
                error,
            }) => {
                warn!("Request to {} failed: {:?}", peer, error);
                self.sync_manager.on_request_failed(request_id);
                self.peer_manager.update_peer(&peer, |p| p.record_failure());
                // Record violation in reputation system (no response from peer)
                let auto_banned = self.reputation_manager.record_violation(&peer, ViolationType::NoResponse);
                if auto_banned {
                    warn!("Auto-banned peer {} for repeated failures", peer);
                    let _ = self.swarm.disconnect_peer_id(peer);
                }
            }

            SynorBehaviourEvent::Identify(identify::Event::Received { peer_id, info, .. }) => {
                debug!("Identified peer {}: {}", peer_id, info.agent_version);
                self.peer_manager.update_peer(&peer_id, |p| {
                    p.user_agent = Some(info.agent_version.clone());
                    for addr in &info.listen_addrs {
                        if !p.addresses.contains(addr) {
                            p.addresses.push(addr.clone());
                        }
                    }
                });

                // Add addresses to Kademlia
                for addr in info.listen_addrs {
                    self.swarm.behaviour_mut().add_address(&peer_id, addr);
                }
            }

            SynorBehaviourEvent::Ping(ping::Event { peer, result, .. }) => {
                match result {
                    Ok(rtt) => {
                        trace!("Ping to {} succeeded: {:?}", peer, rtt);
                        self.peer_manager.update_peer(&peer, |p| {
                            p.latency = Some(rtt);
                        });
                    }
                    Err(e) => {
                        debug!("Ping to {} failed: {}", peer, e);
                    }
                }
            }

            SynorBehaviourEvent::Mdns(mdns::Event::Discovered(peers)) => {
                for (peer_id, addr) in peers {
                    debug!("mDNS discovered peer: {} at {}", peer_id, addr);
                    if self.peer_manager.can_connect_outbound() {
                        self.swarm.behaviour_mut().add_address(&peer_id, addr.clone());
                        if let Err(e) = self.swarm.dial(addr) {
                            debug!("Failed to dial discovered peer: {}", e);
                        }
                    }
                }
            }

            SynorBehaviourEvent::Mdns(mdns::Event::Expired(peers)) => {
                for (peer_id, _) in peers {
                    debug!("mDNS peer expired: {}", peer_id);
                }
            }

            SynorBehaviourEvent::Kademlia(kad::Event::OutboundQueryProgressed { result, .. }) => {
                match result {
                    kad::QueryResult::GetClosestPeers(Ok(ok)) => {
                        for peer in ok.peers {
                            debug!("Kademlia found peer: {:?}", peer);
                        }
                    }
                    kad::QueryResult::Bootstrap(Ok(_)) => {
                        info!("Kademlia bootstrap complete");
                    }
                    _ => {}
                }
            }

            _ => {}
        }
    }

    /// Handles a gossip message.
    async fn handle_gossip_message(&mut self, source: PeerId, message: gossipsub::Message) {
        let topic = message.topic.as_str();

        match topic {
            t if t == topics::BLOCKS => {
                if let Ok(announcement) = borsh::from_slice::<BlockAnnouncement>(&message.data) {
                    debug!("Received block announcement from {}: {}", source, announcement.hash);
                    let _ = self.event_tx.send(NetworkEvent::NewBlock(announcement));
                }
            }
            t if t == topics::TRANSACTIONS => {
                if let Ok(announcement) = borsh::from_slice::<TransactionAnnouncement>(&message.data) {
                    debug!("Received tx announcement from {}: {}", source, announcement.txid);
                    let _ = self.event_tx.send(NetworkEvent::NewTransaction(announcement));
                }
            }
            _ => {
                trace!("Received message on unknown topic: {}", topic);
            }
        }
    }

    /// Handles a request from a peer.
    async fn handle_request(
        &mut self,
        peer: PeerId,
        request: SynorRequest,
        channel: request_response::ResponseChannel<SynorResponse>,
    ) {
        debug!("Received {} request from {}", request.request_type(), peer);

        // Check if peer is banned via reputation system
        if self.reputation_manager.is_banned(&peer) {
            warn!("Ignoring request from banned peer: {}", peer);
            let response = SynorResponse::Error("You are banned".to_string());
            if let Err(e) = self.swarm.behaviour_mut().send_response(channel, response) {
                warn!("Failed to send banned response to {}: {:?}", peer, e);
            }
            return;
        }

        // First layer: Token bucket rate limiting (100 req/s with burst of 200)
        if !self.token_bucket_limiter.check_rate_limit(&peer) {
            // Check if peer is in cooldown
            if let Some(remaining) = self.token_bucket_limiter.cooldown_remaining(&peer) {
                warn!(
                    "Token bucket: Peer {} in cooldown for {} request ({:?} remaining)",
                    peer,
                    request.request_type(),
                    remaining
                );
                self.peer_manager.update_peer(&peer, |p| {
                    p.add_reputation(reputation::INVALID_DATA);
                });
                // Record spam violation in reputation system (may auto-ban)
                let auto_banned = self.reputation_manager.record_violation(&peer, ViolationType::Spam);
                if auto_banned {
                    warn!("Auto-banned peer {} for repeated spam violations", peer);
                    let _ = self.swarm.disconnect_peer_id(peer);
                }
                let response = SynorResponse::Error(format!(
                    "Rate limited (cooldown). Wait {} seconds.",
                    remaining.as_secs()
                ));
                if let Err(e) = self.swarm.behaviour_mut().send_response(channel, response) {
                    warn!("Failed to send cooldown response to {}: {:?}", peer, e);
                }
                return;
            }

            // Rate limited but not in cooldown
            warn!(
                "Token bucket: Rate limited {} request from {} (violations: {})",
                request.request_type(),
                peer,
                self.token_bucket_limiter.violations(&peer)
            );
            self.peer_manager.update_peer(&peer, |p| {
                p.add_reputation(reputation::TIMEOUT);
            });
            // Record spam violation in reputation system
            let auto_banned = self.reputation_manager.record_violation(&peer, ViolationType::Spam);
            if auto_banned {
                warn!("Auto-banned peer {} for spam violations", peer);
                let _ = self.swarm.disconnect_peer_id(peer);
            }
            let response = SynorResponse::Error(
                "Rate limited. Too many requests per second.".to_string()
            );
            if let Err(e) = self.swarm.behaviour_mut().send_response(channel, response) {
                warn!("Failed to send rate limit response to {}: {:?}", peer, e);
            }
            return;
        }

        // Record the request in token bucket limiter
        self.token_bucket_limiter.record_request(&peer);

        // Second layer: Apply type-specific rate limiting (sliding window)
        let rate_limit_result = match &request {
            SynorRequest::GetBlock(_) | SynorRequest::GetBlocks(_) => {
                self.rate_limiters.check_block_request(&peer)
            }
            SynorRequest::GetHeader(_) | SynorRequest::GetHeaders { .. } => {
                self.rate_limiters.check_header_request(&peer)
            }
            SynorRequest::GetTransaction(_) | SynorRequest::GetTransactions(_) => {
                self.rate_limiters.check_transaction_request(&peer)
            }
            _ => {
                // For other requests (peers, status, tips), use global limiter
                self.rate_limiters.global.check(&peer)
            }
        };

        // Handle rate limit violations
        match rate_limit_result {
            RateLimitResult::Denied { retry_after } => {
                warn!(
                    "Rate limited {} request from {} (retry after {:?})",
                    request.request_type(),
                    peer,
                    retry_after
                );
                // Penalize reputation for hitting rate limit
                self.peer_manager.update_peer(&peer, |p| {
                    p.add_reputation(reputation::TIMEOUT);
                });
                // Record slow response violation
                self.reputation_manager.record_violation(&peer, ViolationType::SlowResponse);
                let response = SynorResponse::Error(format!(
                    "Rate limited. Retry after {} seconds.",
                    retry_after.as_secs()
                ));
                if let Err(e) = self.swarm.behaviour_mut().send_response(channel, response) {
                    warn!("Failed to send rate limit response to {}: {:?}", peer, e);
                }
                return;
            }
            RateLimitResult::Cooldown { remaining } => {
                warn!(
                    "Peer {} in cooldown for {} request ({:?} remaining)",
                    peer,
                    request.request_type(),
                    remaining
                );
                // Stronger reputation penalty for repeated violations
                self.peer_manager.update_peer(&peer, |p| {
                    p.add_reputation(reputation::INVALID_DATA);
                });
                // Record spam violation (may auto-ban)
                let auto_banned = self.reputation_manager.record_violation(&peer, ViolationType::Spam);
                if auto_banned {
                    warn!("Auto-banned peer {} for repeated rate limit violations", peer);
                    let _ = self.swarm.disconnect_peer_id(peer);
                }
                let response = SynorResponse::Error(format!(
                    "In cooldown. Wait {} seconds.",
                    remaining.as_secs()
                ));
                if let Err(e) = self.swarm.behaviour_mut().send_response(channel, response) {
                    warn!("Failed to send cooldown response to {}: {:?}", peer, e);
                }
                return;
            }
            RateLimitResult::Allowed => {
                // Record the request for rate limiting
                match &request {
                    SynorRequest::GetBlock(_) | SynorRequest::GetBlocks(_) => {
                        self.rate_limiters.record_block_request(&peer);
                    }
                    SynorRequest::GetHeader(_) | SynorRequest::GetHeaders { .. } => {
                        self.rate_limiters.record_header_request(&peer);
                    }
                    SynorRequest::GetTransaction(_) | SynorRequest::GetTransactions(_) => {
                        self.rate_limiters.record_transaction_request(&peer);
                    }
                    _ => {
                        self.rate_limiters.global.record(&peer);
                    }
                }
            }
        }

        // Process the request - actual implementation would query storage
        let response = match request {
            SynorRequest::GetBlock(_) => SynorResponse::Block(None),
            SynorRequest::GetBlocks(_) => SynorResponse::Blocks(vec![]),
            SynorRequest::GetHeader(_) => SynorResponse::Header(None),
            SynorRequest::GetHeaders { .. } => SynorResponse::Headers(vec![]),
            SynorRequest::GetTransaction(_) => SynorResponse::Transaction(None),
            SynorRequest::GetTransactions(_) => SynorResponse::Transactions(vec![]),
            SynorRequest::GetPeers => {
                let addrs: Vec<String> = self
                    .peer_manager
                    .active_peers()
                    .iter()
                    .flat_map(|p| p.addresses.iter().map(|a| a.to_string()))
                    .take(20)
                    .collect();
                SynorResponse::Peers(addrs)
            }
            SynorRequest::GetStatus => {
                // Would need actual chain state
                SynorResponse::Error("Not implemented".to_string())
            }
            SynorRequest::GetTips => SynorResponse::Tips(vec![]),
            SynorRequest::GetPruningPoint => SynorResponse::PruningPoint(None),
            _ => SynorResponse::Error("Unknown request".to_string()),
        };

        if let Err(e) = self.swarm.behaviour_mut().send_response(channel, response) {
            warn!("Failed to send response to {}: {:?}", peer, e);
        }
    }

    /// Handles a response from a peer.
    async fn handle_response(
        &mut self,
        peer: PeerId,
        request_id: request_response::OutboundRequestId,
        response: SynorResponse,
    ) {
        debug!("Received response from {}", peer);

        // Record success in both peer manager and reputation system
        self.peer_manager.update_peer(&peer, |p| p.record_success());
        self.reputation_manager.record_success(&peer);

        match response {
            SynorResponse::Headers(headers) => {
                self.sync_manager.on_headers_response(headers.clone());
                let _ = self.event_tx.send(NetworkEvent::HeadersReceived(headers));
            }
            SynorResponse::Blocks(blocks) => {
                self.sync_manager.on_blocks_response(request_id, blocks.clone());
                let _ = self.event_tx.send(NetworkEvent::BlocksReceived(blocks));
            }
            _ => {}
        }
    }

    /// Handles a command.
    async fn handle_command(&mut self, cmd: NetworkCommand) -> bool {
        match cmd {
            NetworkCommand::Dial(addr) => {
                if let Err(e) = self.swarm.dial(addr.clone()) {
                    warn!("Failed to dial {}: {}", addr, e);
                }
            }

            NetworkCommand::Disconnect(peer_id) => {
                let _ = self.swarm.disconnect_peer_id(peer_id);
            }

            NetworkCommand::Ban(peer_id) => {
                self.peer_manager.ban(&peer_id);
                let _ = self.swarm.disconnect_peer_id(peer_id);
            }

            NetworkCommand::BroadcastBlock(announcement) => {
                if let Ok(data) = borsh::to_vec(&announcement) {
                    if let Err(e) = self.swarm.behaviour_mut().publish_block(data) {
                        warn!("Failed to publish block: {:?}", e);
                    }
                }
            }

            NetworkCommand::BroadcastTransaction(announcement) => {
                if let Ok(data) = borsh::to_vec(&announcement) {
                    if let Err(e) = self.swarm.behaviour_mut().publish_transaction(data) {
                        warn!("Failed to publish transaction: {:?}", e);
                    }
                }
            }

            NetworkCommand::RequestBlocks { peer, block_ids, response } => {
                let request = SynorRequest::GetBlocks(block_ids);
                let _request_id = self.swarm.behaviour_mut().send_request(&peer, request);
                // Would need to track the response sender
                let _ = response.send(Err(NetworkError::RequestFailed("Not implemented".to_string())));
            }

            NetworkCommand::RequestHeaders { peer, start, max_count, response } => {
                let request = SynorRequest::GetHeaders { start, max_count };
                let _request_id = self.swarm.behaviour_mut().send_request(&peer, request);
                let _ = response.send(Err(NetworkError::RequestFailed("Not implemented".to_string())));
            }

            NetworkCommand::GetPeerCount(response) => {
                let _ = response.send(self.peer_manager.connected_count());
            }

            NetworkCommand::GetSyncStatus(response) => {
                let _ = response.send(self.sync_manager.status());
            }

            NetworkCommand::StartSync => {
                self.sync_manager.start_sync();
            }

            NetworkCommand::Shutdown => {
                return false;
            }
        }

        true
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[tokio::test]
    async fn test_network_handle_clone() {
        let (tx, _rx) = mpsc::channel(1);
        let (event_tx, _) = broadcast::channel(1);

        let handle = NetworkHandle {
            command_tx: tx,
            event_rx: event_tx,
        };

        let _handle2 = handle.clone();
    }
}
