// nac-multi-jurisdiction/src/discovery.rs
// Issue #59: 辖区感知节点发现

use crate::jurisdiction::JurisdictionId;

/// 辖区感知节点发现
pub struct NodeDiscovery {
    known_nodes: Vec<NodeInfo>,
}

#[derive(Debug, Clone)]
pub struct NodeInfo {
    pub node_id: [u8; 32],
    pub jurisdiction_id: JurisdictionId,
    pub endpoint: String,
    pub is_active: bool,
}

impl NodeDiscovery {
    pub fn new() -> Self {
        NodeDiscovery { known_nodes: Vec::new() }
    }

    /// 注册节点
    pub fn register_node(&mut self, info: NodeInfo) {
        self.known_nodes.push(info);
    }

    /// 查找指定辖区的节点
    pub fn find_by_jurisdiction(&self, jid: &JurisdictionId) -> Vec<&NodeInfo> {
        self.known_nodes.iter()
            .filter(|n| &n.jurisdiction_id == jid && n.is_active)
            .collect()
    }

    /// 获取所有活跃节点数量
    pub fn active_count(&self) -> usize {
        self.known_nodes.iter().filter(|n| n.is_active).count()
    }
}

impl Default for NodeDiscovery {
    fn default() -> Self {
        Self::new()
    }
}

/// 辖区感知路由器
pub struct JurisdictionAwareRouter {
    discovery: NodeDiscovery,
}

impl JurisdictionAwareRouter {
    pub fn new(discovery: NodeDiscovery) -> Self {
        JurisdictionAwareRouter { discovery }
    }

    /// 路由到目标辖区
    pub fn route_to(&self, target_jid: &JurisdictionId) -> Option<&NodeInfo> {
        self.discovery.find_by_jurisdiction(target_jid).into_iter().next()
    }
}