#!/usr/bin/env bash
set -Eeuo pipefail

PATH=/usr/local/bin:/usr/bin:/usr/sbin:/sbin:/bin
export PATH
umask 077

# Manual updater for operators without using the web control. The same
# verified TypeScript updater used by the systemd queue performs download,
# extraction and atomic release switching.
PREFIX=${TALLYNOTE_INSTALL_PREFIX:-${TALLYNOTE_PREFIX:-/opt/tallynote}}
DATA_DIR=${TALLYNOTE_DATA_DIR:-/var/lib/tallynote}
CONFIG_DIR=${TALLYNOTE_CONFIG_DIR:-/etc/tallynote}
CONFIG_FILE="$CONFIG_DIR/tallynote.env"
REQUEST_FILE=${TALLYNOTE_UPDATE_REQUEST_FILE:-$DATA_DIR/update-request.json}
NODE=${TALLYNOTE_NODE:-}

node_is_usable() {
  local candidate=$1 major
  [[ -n "$candidate" && -x "$candidate" ]] || return 1
  major=$("$candidate" -p 'process.versions.node.split(".")[0]' 2>/dev/null || true)
  [[ "$major" =~ ^[0-9]+$ && "$major" -ge 24 ]]
}

if [[ -z "$NODE" && -f "$CONFIG_FILE" && ! -L "$CONFIG_FILE" ]]; then
  NODE=$(sed -n 's/^TALLYNOTE_NODE=//p' "$CONFIG_FILE" | head -n 1)
fi

die() { printf 'tallynote update: %s\n' "$*" >&2; exit 1; }
version_sort_desc() {
  if sort -V </dev/null >/dev/null 2>&1; then
    sort -V -r
    return
  fi
  awk -F'[.-]' '{ printf "%020d.%020d.%020d.%s\t%s\n", $1, $2, $3, ($4 == "" ? "~" : $4), $0 }' \
    | sort -r | cut -f2-
}
[[ ${EUID:-$(id -u)} -eq 0 ]] || die 'must run as root'

if [[ "${1:-}" == "--rollback" ]]; then
  current="$PREFIX/current"
  [[ -L "$current" ]] || die 'current release is not a symlink'
  current_target=$(readlink -f -- "$current")
  current_name=$(basename -- "$current_target")
  [[ "$current_name" =~ ^[0-9]+\.[0-9]+\.[0-9]+(-[0-9A-Za-z.-]+)?(\+[0-9A-Za-z.-]+)?$ ]] || die 'current release version is invalid'
  mapfile -t releases < <(
    find "$PREFIX/releases" -mindepth 1 -maxdepth 1 -type d -printf '%p\n' \
      | awk -F/ '$NF ~ /^[0-9]+\.[0-9]+\.[0-9]+([.-][0-9A-Za-z.-]+)?$/' \
      | version_sort_desc
  )
  previous=''
  found_current=0
  for release in "${releases[@]}"; do
    release_target=$(readlink -f -- "$release")
    if [[ "$release_target" == "$current_target" ]]; then
      found_current=1
      continue
    fi
    if (( found_current )); then
      previous=$release
      break
    fi
  done
  [[ -n "$previous" && -d "$previous" ]] || die 'no previous release available'
  was_active=0
  if systemctl is-active --quiet tallynote.service; then was_active=1; fi
  if (( was_active )); then systemctl stop tallynote.service; fi
  tmp="$PREFIX/.current-rollback-$$-${RANDOM}"
  [[ ! -e "$tmp" && ! -L "$tmp" ]] || die 'rollback temporary path already exists'
  ln -s -- "$previous" "$tmp"
  mv -Tf -- "$tmp" "$current"
  if (( was_active )); then systemctl start tallynote.service; fi
  printf 'rolled back to %s\n' "$(basename -- "$previous")"
  exit 0
fi

[[ -f "$REQUEST_FILE" ]] || die "no queued update request at $REQUEST_FILE"
[[ -L "$PREFIX/current" ]] || die 'current release is not a symlink'

# Prefer the systemd runner, which performs the post-switch health check and
# rollback. The fallback remains useful in development installations where the
# privileged helper has not been installed yet.
if [[ -x /usr/local/libexec/tallynote-update-runner ]]; then
  exec /usr/local/libexec/tallynote-update-runner
fi
if [[ -z "$NODE" ]]; then
  NODE=$(command -v node || true)
fi
node_is_usable "$NODE" || die 'Node.js 24+ not found'
CLI="$PREFIX/current/dist/server/cli/update.js"
[[ -f "$CLI" ]] || die 'update CLI not found'

was_active=0
if systemctl is-active --quiet tallynote.service; then was_active=1; fi
if (( was_active )); then systemctl stop tallynote.service; fi
set +e
"$NODE" "$CLI" --request-file "$REQUEST_FILE"
result=$?
set -e
if (( result != 0 )); then
  rm -f -- "$REQUEST_FILE"
  if (( was_active )); then systemctl start tallynote.service || true; fi
  die 'update failed; the previous release remains active'
fi
if (( was_active )); then systemctl start tallynote.service || { rm -f -- "$REQUEST_FILE"; die 'updated service failed to start'; }; fi
rm -f -- "$REQUEST_FILE"
printf 'update completed; inspect the update page for details\n'