#!/usr/bin/env bash
# orca-watchdog.sh — lead-side watchdog meta-timer (P09, C-11).
#
# Runs every 30s via orca-watchdog.timer. Checks whether
# orca-aggregate.sh has run in the last N seconds (default 30s — 3x the
# 10s cadence). If not: fires a structured alert via
# `logger -t orca-watchdog -p user.err "aggregator starvation detected"`.
# The check compares the mtime of /etc/orca/state/cluster.json to the
# current time.

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=lib/orca-log.sh
. "$SCRIPT_DIR/lib/orca-log.sh"

ORCA_LOG_ACTOR="spiffe://orca/cli/watchdog"

STATE_DIR="${ORCA_STATE_DIR:-/etc/orca/state}"
CLUSTER_JSON="$STATE_DIR/cluster.json"
STARVATION_THRESHOLD="${ORCA_WATCHDOG_THRESHOLD:-30}"

alert() {
	logger -t orca-watchdog -p user.err "aggregator starvation detected: $1"
}

if [ ! -f "$CLUSTER_JSON" ]; then
	alert "cluster.json absent at $CLUSTER_JSON"
	orca_log_error "watchdog" "-" "starved" "cluster.json absent"
	exit 0
fi

now="$(date +%s)"
mtime="$(stat -c %Y "$CLUSTER_JSON" 2>/dev/null || stat -f %m "$CLUSTER_JSON" 2>/dev/null || echo 0)"
age=$((now - mtime))

if [ "$age" -ge "$STARVATION_THRESHOLD" ]; then
	alert "cluster.json age ${age}s >= threshold ${STARVATION_THRESHOLD}s"
	orca_log_error "watchdog" "-" "starved" "age=${age}s threshold=${STARVATION_THRESHOLD}s"
else
	orca_log_info "watchdog" "-" "ok" "age=${age}s threshold=${STARVATION_THRESHOLD}s"
fi