omelet

#!/bin/sh

# A manager for Glorious-Eggroll's custom proton versions
# https://github.com/GloriousEggroll/proton-ge-custom/tags

ERR_MISSING_DEP=11
ERR_BAD_USAGE=12
ERR_BROKEN_DOWNLOAD=13
ERR_TAG_ALREADY_PRESENT=14
ERR_TAG_NOT_FOUND=15
_myname="$(basename "$0")"

__usage () {
  cat << EOH
$0 get [latest|<version>]
$0 list [-l]

Manage Glorious-Eggroll's custom proton versions.

- get: download and extirp a version to the right location(s)
  'latest' is an alias to the most recent release name in the list of published
  releases
- list: get a list of available versions.
  -l: only locally available versions
EOH
}

__req () {
  command -v "$1" >/dev/null 2>&1
}

__err () {
  echo "$@" >&2
}

__die () {
  __err "$1"
  exit "${2:-10}"
}

for _dep in curl jq bsdtar; do
  __req "$_dep" || __die "missing $_dep" $ERR_MISSING_DEP
done

if [ -z "$OMELET_DEST" ]; then
  for _dest in \
   ~/.var/app/com.valvesoftware.Steam/.local/share/Steam/compatibilitytools.d \
   ; do
    [ -d "$_dest" ] && OMELET_DEST="$_dest"
  done
fi

## TODO: only create tmpdir if needed

_tmpdir="$(mktemp -d -t "$_myname.XXXXXX")"

__cleanup () {
  [ -d "$_tmpdir" ] && rm -r "$_tmpdir"
}

trap __cleanup INT TERM

__get_releases () {
  curl --location \
   --header "Accept: application/vnd.github+json" \
   --header "X-GitHub-Api-Version: 2022-11-28" \
   --output versions.json \
   https://api.github.com/repos/GloriousEggroll/proton-ge-custom/releases
}

__do_get () {
  cd "$_tmpdir"
  [ -r versions.json ] || __get_releases
  case "$1" in
    latest)
      # I didn't write that jq(1) code. Don't ask.
      jq -r '.[] | [.published_at, .tag_name] | join(",")' < versions.json |
       sort |
       tail -n 1 |
       # we get a single line of sorted releases (the latest one)
       while IFS=',' read -r _date _tag; do
         __do_get "$_tag"
       done
    ;;
    *)
      _tag="$1"
      # bail if we already have a matching release in the
      # compatibilitytools.d dir.
      if [ -d "$OMELET_DEST/$_tag" ]; then
        __die "$OMELET_DEST/$_tag already exists, nothing to do" $ERR_TAG_ALREADY_PRESENT
      fi
      if [ "$(jq -r --arg _tag "$_tag" '.[]|select(.tag_name == $_tag ).assets[]' < versions.json | wc -l)" -lt 1 ]; then
        __die "Couldn't find any release named '$_tag' (it might just be too old and $0 can't deal with it)." $ERR_TAG_NOT_FOUND
      fi
      jq -r --arg _tag "$_tag" '.[]|select(.tag_name == $_tag ).assets[]| [.browser_download_url, .name] | join(",")' < versions.json |
       while IFS=',' read -r _url _name; do
         # we download the assets for that release
         curl --location --output "$_name" "$_url"
       done
      find . -iname '*.sha*sum' |
       while IFS= read -r _f; do
         # shasum checks never hurt
         case "$_f" in
           *.sha512sum) sha512sum -c "$_f" || __die "broken download" $ERR_BROKEN_DOWNLOAD ;;
           *.sha256sum) sha256sum -c "$_f" || __die "broken download" $ERR_BROKEN_DOWNLOAD ;;
         esac
       done
      find . -iname '*.tar.gz' |
       while IFS= read -r _archive; do
         bsdtar xvf "$_archive" -C "$OMELET_DEST"
       done
    ;;
  esac
}

case "$1" in
  get) shift; __do_get "$@" ;;
  list) shift; __do_list "$@" ;;
  -h|help) __usage ; exit 0;;
  *) __die "$(__usage)" $ERR_BAD_USAGE ;;
esac

__cleanup