use redis::AsyncCommands;
use tracing::info;

use crate::inference::Detection;

const ALERT_CHANNEL: &str = "channel:print_alerts";

/// Fast-paths a failure alert out to whatever's listening.
pub struct Reporter {
    redis: redis::aio::MultiplexedConnection,
}

impl Reporter {
    pub async fn connect(redis_url: &str) -> anyhow::Result<Self> {
        let client = redis::Client::open(redis_url)?;
        let redis = client.get_multiplexed_tokio_connection().await?;
        Ok(Self { redis })
    }

    /// Publishes to Redis (real — this is what `continuum-backend`'s
    /// WebSocket fan-out subscribes to, for live operator-console alerts).
    ///
    /// A real version would also `INSERT` into Postgres here via `sqlx` for
    /// the permanent audit trail — that's left as a `println!` for now;
    /// come back to it once async SQL feels comfortable.
    pub async fn report(&mut self, printer_id: &str, detections: &[Detection]) -> anyhow::Result<()> {
        let best = &detections[0];
        info!(printer_id, label = %best.label, confidence = best.confidence, "reporting print failure");

        let payload = serde_json::json!({
            "printerId": printer_id,
            "label": best.label,
            "confidence": best.confidence,
        });
        self.redis.publish::<_, _, ()>(ALERT_CHANNEL, payload.to_string()).await?;

        println!("(would also INSERT this alert into Postgres for the audit trail)");

        Ok(())
    }
}