#!/usr/bin/env bash
# ZFS scrub annotation script for Grafana
# Usage: zfs-scrub-annotations.sh {start|stop}
# Required env: GRAFANA_URL, STATE_DIR
# Required on PATH: zpool, curl, jq, paste, date, grep, sed

set -euo pipefail

ACTION="${1:-}"
GRAFANA_URL="${GRAFANA_URL:?GRAFANA_URL required}"
STATE_DIR="${STATE_DIR:?STATE_DIR required}"

case "$ACTION" in
  start)
    POOLS=$(zpool list -H -o name | paste -sd ', ')
    NOW_MS=$(date +%s%3N)

    RESPONSE=$(curl -sf --max-time 5 \
      -X POST "$GRAFANA_URL/api/annotations" \
      -H "Content-Type: application/json" \
      -d "$(jq -n --arg text "ZFS scrub: $POOLS" --argjson time "$NOW_MS" \
        '{time: $time, text: $text, tags: ["zfs-scrub"]}')" \
    ) || exit 0

    echo "$RESPONSE" | jq -r '.id' > "$STATE_DIR/annotation-id"
    ;;

  stop)
    ANN_ID=$(cat "$STATE_DIR/annotation-id" 2>/dev/null) || exit 0
    [ -z "$ANN_ID" ] && exit 0

    NOW_MS=$(date +%s%3N)

    RESULTS=""
    while IFS= read -r pool; do
      scan_line=$(zpool status "$pool" | grep "scan:" | sed 's/^[[:space:]]*//')
      RESULTS="${RESULTS}${pool}: ${scan_line}"$'\n'
    done < <(zpool list -H -o name)

    TEXT=$(printf "ZFS scrub completed\n%s" "$RESULTS")

    curl -sf --max-time 5 \
      -X PATCH "$GRAFANA_URL/api/annotations/$ANN_ID" \
      -H "Content-Type: application/json" \
      -d "$(jq -n --arg text "$TEXT" --argjson timeEnd "$NOW_MS" \
        '{timeEnd: $timeEnd, text: $text}')" || true

    rm -f "$STATE_DIR/annotation-id"
    ;;

  *)
    echo "Usage: $0 {start|stop}" >&2
    exit 1
    ;;
esac