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use tokio::sync::watch;
use bat_markets_core::{ErrorKind, HealthReport, MarketError, Result};
/// RAII-style watcher for runtime status changes.
///
/// Dropping the watcher releases the local subscription. There is no global
/// `un_watch` method because Rust ownership already scopes the subscription.
pub struct StatusWatch {
receiver: watch::Receiver<HealthReport>,
}
impl StatusWatch {
pub(crate) const fn new(receiver: watch::Receiver<HealthReport>) -> Self {
Self { receiver }
}
/// Return the current cached status snapshot without waiting.
#[must_use]
pub fn current(&self) -> HealthReport {
self.receiver.borrow().clone()
}
/// Wait for the next status change.
pub async fn recv(&mut self) -> Result<HealthReport> {
self.receiver.changed().await.map_err(|error| {
MarketError::new(
ErrorKind::TransportError,
format!("status watch receive failed: {error}"),
)
})?;
Ok(self.current())
}
/// Explicitly end the watch.
///
/// This mirrors other watch handles. Dropping the handle is equivalent for
/// the local health subscription.
pub async fn shutdown(self) -> Result<()> {
Ok(())
}
}