struct Lease {
    _permit: OwnedSemaphorePermit,
    metrics: Arc<Metrics>,
}
impl Drop for Lease {
    fn drop(&mut self) {
        self.metrics
            .http3_active_connections
            .fetch_sub(1, Ordering::Relaxed);
        self.metrics
            .active_connections
            .fetch_sub(1, Ordering::Relaxed);
    }
}
#[allow(clippy::too_many_arguments)]
fn log_protocol_error(
    state: &App,
    kind: &'static str,
    detail: impl std::fmt::Display,
    peer: SocketAddr,
    local: SocketAddr,
    status: u16,
    authority: Option<String>,
    host: Option<String>,
    sni: Option<String>,
) {
    let resolved = state.config.load().resolve_logging_vhost(
        local,
        true,
        None,
        authority.as_deref(),
        host.as_deref(),
        sni.as_deref(),
    );
    let (vhost, matched_by) = resolved
        .map(|resolved| (Some(resolved.vhost), resolved.matched_by))
        .unwrap_or((None, "none"));
    state.logs.push_protocol_error_attributed(
        kind,
        detail,
        peer,
        local,
        "quic",
        "3",
        status,
        sni,
        authority.or(host),
        vhost,
        matched_by,
    );
}

/// Service-level breadcrumbs for a full HTTP/3 GET / navigation. User-provided
/// query strings, headers and error details must not reach this diagnostic.
#[allow(clippy::too_many_arguments)]
fn log_root_navigation(
    stage: &'static str,
    peer: SocketAddr,
    local: SocketAddr,
    sni: &Option<String>,
    stream_id: &str,
    phase: &'static str,
    response_status: u16,
    body_bytes_sent: u64,
    cancelled: bool,
) {
    match stage {
        "started" => tracing::info!(
            peer=%peer, local=%local, sni=?sni, stream_id=%stream_id,
            method="GET", path="/", "http3_navigation_started"
        ),
        "complete" => tracing::info!(
            peer=%peer, local=%local, sni=?sni, stream_id=%stream_id,
            method="GET", path="/", response_status, body_bytes_sent,
            "http3_navigation_complete"
        ),
        "interrupted" => tracing::warn!(
            peer=%peer, local=%local, sni=?sni, stream_id=%stream_id,
            method="GET", path="/", phase, response_status, body_bytes_sent,
            cancelled, "http3_navigation_interrupted"
        ),
        _ => {}
    }
}

fn log_h3_response_complete(peer: SocketAddr, stream_id: &str, response_status: u16, body_bytes_sent: u64) {
    tracing::debug!(
        peer=%peer, stream_id=%stream_id, response_status, body_bytes_sent,
        "HTTP/3 response completed"
    );
}