#!/bin/bash
set -euo pipefail

# pve-nag-buster (v03) https://github.com/foundObjects/pve-nag-buster
# Copyright (C) 2019 /u/seaQueue (reddit.com/u/seaQueue)
#
# Removes Proxmox VE 5.x+ license nags automatically after updates
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

# ensure a predictable environment
PATH=/usr/sbin:/usr/bin:/sbin:/bin
unalias -a

# installer main body:
_main() {
  # ensure $1 exists so 'set -u' doesn't error out
  (("$#" == 0)) && { set -- ""; } >&/dev/null

  case "$1" in
    "--emit")
      # call the emit_script() function to stdout and exit, use this to verify
      # that the base64 encoded script below isn't doing anything malicious
      # does not require root
      emit_script
      ;;
    "--uninstall")
      # uninstall, requires root
      assert_root
      _uninstall
      ;;
    "--install" | "--offline" | "")
      # install dpkg hooks, requires root
      assert_root
      _install "$@"
      ;;
    *)
      # unknown flags, print usage and exit
      _usage
      ;;
  esac
  exit 0
}

_uninstall() {
  set -x
  [ -f "/etc/apt/apt.conf.d/86pve-nags" ] &&
    rm -f "/etc/apt/apt.conf.d/86pve-nags"
  [ -f "/usr/share/pve-nag-buster.sh" ] &&
    rm -f "/usr/share/pve-nag-buster.sh"

  echo "Script and dpkg hooks removed, please manually remove /etc/apt/sources.list.d/pve-no-subscription.list if desired"
  exit 0
}

_install() {
  # create hooks and no-subscription repo list, install hook script, run once

  RELEASE=$(awk -F"[)(]+" '/VERSION=/ {print $2}' /etc/os-release)

  # create the pve-no-subscription list
  echo "Creating PVE no-subscription repo list ..."
  cat <<- EOF > "/etc/apt/sources.list.d/pve-no-subscription.list"
	# .list file automatically generated by pve-nag-buster at $(date)
	#
	# If pve-nag-buster is installed again this file will be overwritten
	#

	deb http://download.proxmox.com/debian/pve $RELEASE pve-no-subscription
	EOF

  # create dpkg pre/post install hooks for persistence
  echo "Creating dpkg hooks in /etc/apt/apt.conf.d ..."
  cat <<- 'EOF' > "/etc/apt/apt.conf.d/86pve-nags"
	DPkg::Pre-Install-Pkgs {
	    "while read -r pkg; do case $pkg in *proxmox-widget-toolkit* | *pve-manager*) touch /tmp/.pve-nag-buster && exit 0; esac done < /dev/stdin";
	};

	DPkg::Post-Invoke {
	    "[ -f /tmp/.pve-nag-buster ] && { /usr/share/pve-nag-buster.sh; rm -f /tmp/.pve-nag-buster; }; exit 0";
	};
	EOF

  echo "Installing script to /usr/share/pve-nag-buster.sh"
  temp=''
  if [[ "$1" == "--offline" ]]; then
    # offline mode, emit stored script
    temp="$(mktemp)" && trap "rm -f $temp" EXIT
    emit_script > "$temp"
  elif [ -f "pve-nag-buster.sh" ]; then
    # local copy available
    temp="pve-nag-buster.sh"
  else
    # fetch from github
    temp="$(mktemp)" && trap "rm -f $temp" EXIT
    wget https://raw.githubusercontent.com/foundObjects/pve-nag-buster/master/pve-nag-buster.sh \
      -O "$temp"
  fi
  install -o root -m 0550 "$temp" "/usr/share/pve-nag-buster.sh"
  /usr/share/pve-nag-buster.sh
  return 0
}

# emit a stored copy of pve-nag-buster.sh offline -- this is intended to be used during
# offline provisioning where we don't have access to github or a full cloned copy of the
# project

# run 'install.sh --emit' to dump stored script to stdout

# Important: if you're not me you should probably decode this and read it to make sure I'm not doing
#            something malicious like mining dogecoin or stealing your valuable cat pictures

# pve-nag-buster.sh (v03) encoded below:

emit_script() {
  base64 -d << 'YEET' | unxz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YEET
}

assert_root() { [ $(id -u) -eq '0' ] || { echo "This action requires root." && exit 0; }; }
err() { echo "Err '${FUNCNAME[1]}': $*" >&2; }
_usage() { echo "Usage: $(basename "$0") (--emit|--offline|--uninstall)"; }

_main "$@"