#!/usr/bin/env bash
# Install the failure notifier and hook every fleet user unit on this box.
#   services/althing-notify-failure/install.sh [--dry-run]
#
# Idempotent. Re-running adds hooks for units that appeared since last time.
set -euo pipefail
cd "$(dirname "$0")"
DRY="${1:-}"
UD="${HOME}/.config/systemd/user"
BIN="${HOME}/.local/bin"

# dbus.service is systemd's own plumbing, not a fleet service -- excluded.
# althing-notify-failure@ is excluded because a notifier must never report
# itself (see the template's comment).
SKIP_RE='^(dbus|althing-notify-failure@).*'

run() { if [ "$DRY" = "--dry-run" ]; then echo "  would: $*"; else "$@"; fi; }

echo "== installing the notifier =="
run install -Dm755 althing-notify-failure "${BIN}/althing-notify-failure"
run install -Dm644 althing-notify-failure@.service "${UD}/althing-notify-failure@.service"

echo "== hooking fleet user units =="
mapfile -t UNITS < <(systemctl --user list-units --type=service --state=running --no-pager \
                     | awk '{print $1}' | grep '\.service$' | grep -Ev "$SKIP_RE")
for u in "${UNITS[@]}"; do
  d="${UD}/${u}.d"
  run mkdir -p "$d"
  run install -m644 onfailure-drop-in.conf "${d}/10-onfailure-althing.conf"
  echo "  hooked ${u}"
done

run systemctl --user daemon-reload
echo "== ${#UNITS[@]} unit(s) hooked =="