#!/bin/bash

set -eu

##
## This script must match the API the temporary Steam UI updater wants of us, including this file
##

unset tmpdir
cleanup() { rm -rf /tmp/steamos-update.pid; [[ -z ${tmpdir-} ]] || rm -rf --one-file-system -- "$tmpdir"; }
trap cleanup EXIT
touch /tmp/steamos-update.pid
info() { echo >&2 "$*"; }
die() { info "!! $*"; exit 1; }


checkmode=""
error=""
beta=""
debug=""

while [[ $# -ge 1 ]]; do
  case "$1" in
    "check") checkmode=1 ;;
    "--beta") beta=1 ;;
    "-d") debug=1 ;;
    *)
      error=1
      info "Unknown option \"$1\""
    ;;
  esac
  shift
done

if [[ -n $error ]]; then
  echo >&2 "!! Usage: $0 [check]"
  exit 1
fi

atomupd_args=(--manifest "/usr/share/steamos-update/manifest-0.json")
[[ -n $debug ]] && atomupd_args+=(-d)

# Determine which branches to check.
check_rel=0
check_rc=0
check_beta=0
check_bc=0
check_main=0

if [[ -n $beta ]]; then
  info "'--beta' is deprecated; use 'steamos-select-branch beta' then 'steamos-update'"
  check_beta=1
else
  branch_path="/var/lib/steamos-branch"
  branch=$(cat "$branch_path" 2> /dev/null || echo "rel")
  case "$branch" in
    "rel")
      check_rel=1
      ;;
    "rc")
      check_rel=1
      check_rc=1
      ;;
    "beta")
      check_beta=1
      ;;
    "bc")
      check_beta=1
      check_bc=1
      ;;
    "main")
      check_main=1
      ;;
    *)
      echo "unknown branch name in $branch_path: $branch" 1>&2
      exit 1
      ;;
  esac
fi

# Get the buildid for each variant.
get_buildid () {
  if [[ $1 = 0 ]]; then
    exit 0
  fi

  query="$(sudo steamos-atomupd-client "${atomupd_args[@]}" --variant="$2" --query-only)"
  if [[ -z $query ]]; then
    info "Failed to check for updates"
    exit 1 # Unknown failure
  fi

  jq -r '.minor.candidates[0].image.buildid | select(type == "string")' <<< "$query"
}

buildid_rel="$(get_buildid $check_rel steamdeck)"
buildid_rc="$(get_buildid $check_rc steamdeck-rc)"
buildid_beta="$(get_buildid $check_beta steamdeck-beta)"
buildid_bc="$(get_buildid $check_bc steamdeck-bc)"
buildid_main="$(get_buildid $check_main steamdeck-main)"

if [[ -n $debug ]]; then
  info "buildid_rel=$buildid_rel"
  info "buildid_rc=$buildid_rc"
  info "buildid_beta=$buildid_beta"
  info "buildid_bc=$buildid_bc"
  info "buildid_main=$buildid_main"
fi

# Choose the variant with the newest buildid.
chosen_buildid=""
chosen_variant=""

if [[ "$buildid_rel" > "$chosen_buildid" ]]; then
  chosen_buildid="$buildid_rel"
  chosen_variant="steamdeck"
fi
if [[ "$buildid_rc" > "$chosen_buildid" ]]; then
  chosen_buildid="$buildid_rc"
  chosen_variant="steamdeck-rc"
fi
if [[ "$buildid_beta" > "$chosen_buildid" ]]; then
  chosen_buildid="$buildid_beta"
  chosen_variant="steamdeck-beta"
fi
if [[ "$buildid_bc" > "$chosen_buildid" ]]; then
  chosen_buildid="$buildid_bc"
  chosen_variant="steamdeck-bc"
fi
if [[ "$buildid_main" > "$chosen_buildid" ]]; then
  chosen_buildid="$buildid_main"
  chosen_variant="steamdeck-main"
fi

if [[ -z "$chosen_variant" ]]; then
  info "No update available"
  exit 7
fi

manifest_path="/etc/steamos-atomupd/manifest.json"
current_buildid=$(jq -r .buildid < "$manifest_path")
if [[ "$current_buildid" = "$chosen_buildid" ]]; then
  info "No update available"
  exit 7
fi

if [[ -n $debug ]]; then
  info "chosen_buildid=$chosen_buildid"
  info "chosen_variant=$chosen_variant"
fi

# Update is available
info "Update available"

# Check mode, return success for update available
if [[ -n ${checkmode-} ]]; then
  echo "$chosen_buildid"
  exit 0
fi

# Not check mode. Update!
do_atomupd() { sudo steamos-atomupd-client "${atomupd_args[@]}" --variant="$chosen_variant" "$@"; }

if do_atomupd; then
  info "Applied an update"
  exit 0
else
  info "Update failed"
  exit 1
fi