//! Reporter wrapper that forwards finalization events to the
//! simulation harness.
//!
//! Custom [`EngineDefinition`](super::engine::EngineDefinition)
//! implementations should include a [`MonitorReporter`] in their
//! reporter chain so the harness can track finalization progress.

use super::tracker::FinalizationUpdate;
use commonware_actor::Feedback;
use commonware_consensus::{Block, Reporter, marshal::Update};
use commonware_cryptography::PublicKey;
use commonware_utils::channel::mpsc;

/// Wraps another [`Reporter`] and forwards marshal [`Update`]
/// finalization events to the simulation harness via a monitor channel.
///
/// Place this in the marshal reporter chain so it intercepts
/// [`Update::Tip`] events before delegation.
#[derive(Clone)]
pub struct MonitorReporter<P: PublicKey, R> {
    inner: R,
    monitor: mpsc::UnboundedSender<FinalizationUpdate<P>>,
    pk: P,
}

impl<P: PublicKey, R> MonitorReporter<P, R> {
    /// Create a new monitor reporter.
    ///
    /// - `pk`: the public key of the validator this reporter belongs to.
    /// - `monitor`: channel for sending finalization updates to the harness.
    /// - `inner`: the wrapped reporter to delegate to after interception.
    pub const fn new(
        pk: P,
        monitor: mpsc::UnboundedSender<FinalizationUpdate<P>>,
        inner: R,
    ) -> Self {
        Self { inner, monitor, pk }
    }
}

impl<P, B, R> Reporter for MonitorReporter<P, R>
where
    P: PublicKey,
    B: Block,
    R: Reporter<Activity = Update<B>>,
{
    type Activity = Update<B>;

    fn report(&mut self, activity: Self::Activity) -> Feedback {
        if let Update::Tip(round, height, ref digest) = activity {
            let _ = self.monitor.send(FinalizationUpdate {
                pk: self.pk.clone(),
                round,
                height,
                block_digest: digest.as_ref().to_vec(),
            });
        }
        self.inner.report(activity)
    }
}