nodedb 0.0.0-beta.1

use std::net::SocketAddr;

use serde::{Deserialize, Serialize};

/// Distributed cluster configuration.
///
/// Example TOML:
/// ```toml
/// [cluster]
/// node_id = 1
/// listen = "0.0.0.0:9400"
/// seed_nodes = ["10.0.0.1:9400", "10.0.0.2:9400"]
/// num_groups = 4
/// replication_factor = 3
/// ```
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ClusterSettings {
    /// Unique node ID within the cluster. Must be unique and non-zero.
    pub node_id: u64,

    /// Address to bind the Raft RPC QUIC listener.
    pub listen: SocketAddr,

    /// Seed node addresses for cluster formation or joining.
    /// On first startup, the first reachable seed bootstraps the cluster.
    /// Subsequent nodes join by contacting any seed.
    pub seed_nodes: Vec<SocketAddr>,

    /// Number of Raft groups to create on bootstrap. Each group owns
    /// a subset of the 1024 vShards. Default: 4.
    #[serde(default = "default_num_groups")]
    pub num_groups: u64,

    /// Replication factor — number of replicas per Raft group.
    /// Default: 3. Single-node clusters use RF=1 automatically.
    #[serde(default = "default_replication_factor")]
    pub replication_factor: usize,
}

fn default_num_groups() -> u64 {
    4
}

fn default_replication_factor() -> usize {
    3
}

impl ClusterSettings {
    /// Validate cluster configuration.
    pub fn validate(&self) -> crate::Result<()> {
        if self.node_id == 0 {
            return Err(crate::Error::Config {
                detail: "cluster.node_id must be non-zero".into(),
            });
        }
        if self.seed_nodes.is_empty() {
            return Err(crate::Error::Config {
                detail: "cluster.seed_nodes must contain at least one address".into(),
            });
        }
        if self.num_groups == 0 {
            return Err(crate::Error::Config {
                detail: "cluster.num_groups must be at least 1".into(),
            });
        }
        if self.replication_factor == 0 {
            return Err(crate::Error::Config {
                detail: "cluster.replication_factor must be at least 1".into(),
            });
        }
        Ok(())
    }
}