//! # `chanora_state`
//!
//! Authoritative client-side mirror of server state: server identity,
//! channel tree, client list, our own connection state. Owns the
//! reducers that fold protocol events into a snapshot, and the
//! deltas that the bridge publishes to Flutter view-models
//! (per SAD §7.2 and SDD §5).
//!
//! ## Status
//!
//! Scaffold only.

#![forbid(unsafe_code)]
#![warn(missing_docs)]

use thiserror::Error;

/// Errors raised while reducing protocol events into state or
/// producing deltas for the bridge.
#[derive(Debug, Error)]
pub enum StateError {
    /// Reducer received an event referencing an unknown entity.
    #[error("unknown entity: {0}")]
    Unknown(&'static str),
    /// A reducer invariant was violated (e.g. two clients claiming
    /// the same id).
    #[error("state invariant: {0}")]
    Invariant(&'static str),
}

/// Coarse connection lifecycle states surfaced to the bridge.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum ConnectionState {
    /// No connection attempt yet, or fully disconnected.
    Idle,
    /// Handshake in progress.
    Connecting,
    /// Initial state snapshot has been received; ready for use.
    Ready,
    /// Connection lost; will not auto-reconnect at this stage.
    Lost,
}

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

    #[test]
    fn state_transitions_compile() {
        let _ = ConnectionState::Idle;
    }
}