#!/bin/zsh
set -euo pipefail

readonly LAUNCH_DAEMON="/Library/LaunchDaemons/org.hol.guard.machine-health.plist"
readonly ROLLBACK_PLIST="/private/var/root/org.hol.guard.machine-health.rollback.plist"

[[ "$(uname -s)" == "Darwin" ]] || exit 1
[[ "$(uname -m)" == "arm64" || "$(uname -m)" == "x86_64" ]] || exit 1
df -Pk / | awk 'NR == 2 { exit !($4 >= 524288) }'
if [[ -L "${LAUNCH_DAEMON}" || ( -e "${LAUNCH_DAEMON}" && ! -f "${LAUNCH_DAEMON}" ) ]]; then
  exit 1
fi
if [[ -f "${LAUNCH_DAEMON}" ]]; then
  /usr/bin/install -o root -g wheel -m 0600 "${LAUNCH_DAEMON}" "${ROLLBACK_PLIST}"
else
  /bin/rm -f "${ROLLBACK_PLIST}"
fi
exit 0
