//! Whether the agent's own harness paused its turn loop, as the agent itself
//! reports it.
//!
//! Part of the turn-state header the agent publishes on
//! `swarm_queue_client::agent_state_subject`, beside [`crate::agent_login::Login`];
//! swarm-controller decodes it out of that header with this same type.

/// The hive-pause fields of an agent's turn-state header.
#[derive(Debug, Clone, Default, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
pub struct HivePause {
    /// Why the harness paused its own turn loop; present only while that
    /// pause is in force. An operator's pause (`hivectl pause`, the
    /// dashboard) is not reported here, and neither is any pause by a harness
    /// that predates the field, so absence says nothing about `agent_state`.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub paused_by_hive: Option<String>,
}

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

    #[test]
    fn a_header_without_the_field_decodes_as_not_paused_by_the_hive() {
        let header = serde_json::json!({ "agent_state": "paused", "needs_login": false });
        let decoded: HivePause = serde_json::from_value(header).expect("an old header decodes");
        assert_eq!(decoded.paused_by_hive, None);
    }

    #[test]
    fn the_reason_round_trips_and_an_absent_one_is_not_sent() {
        let sent = HivePause {
            paused_by_hive: Some("skipped get_loose_ends".to_owned()),
        };
        let value = serde_json::to_value(&sent).expect("serialises");
        assert_eq!(value["paused_by_hive"], "skipped get_loose_ends");
        let decoded: HivePause = serde_json::from_value(value).expect("decodes");
        assert_eq!(decoded, sent);

        let none = serde_json::to_value(HivePause::default()).expect("serialises");
        assert!(none.as_object().expect("an object").is_empty());
    }
}