#!/usr/bin/env bash
# Daily AUR rebuild for the [tanin] binary repo.
#
#   aur-autoupdate.sh setup   # one-time: install devtools + create the chroot
#   aur-autoupdate.sh run     # the daily job (driven by the systemd user timer)
#   aur-autoupdate.sh status  # show what each package would do, without building
#
# What it does on `run`:
#   * fetch each AUR package's PKGBUILD repo into a cache,
#   * build it in a clean chroot (devtools) — no build deps leak into the host,
#       no interactive sudo (see the shipped sudoers drop-in),
#   * but skip non -git packages whose AUR version is unchanged (calamares etc.
#       don't get rebuilt every day for nothing); -git packages always rebuild,
#   * repo-add the fresh packages into tanin.db, prune superseded files,
#   * if TANIN_PUBLISH_CMD is set, run it to upload (hosting is not wired yet,
#       so by default this only refreshes the LOCAL repo dir).
#
# Config (env overrides):
#   TANIN_REPO_DIR    output repo dir            (default ~/projects/tanin-repo)
#   TANIN_CHROOT      clean chroot location      (default ~/.cache/tanin-chroot)
#   TANIN_AUR_CACHE   AUR clone + state cache    (default ~/.cache/tanin-aur)
#   TANIN_PUBLISH_CMD upload hook, e.g. an rsync (default empty = local only)
set -uo pipefail

REPO_NAME="tanin"
OUT="${TANIN_REPO_DIR:-$HOME/projects/tanin-repo}"
DB="$OUT/$REPO_NAME.db.tar.zst"
CHROOT="${TANIN_CHROOT:-$HOME/.cache/tanin-chroot}"
CACHE="${TANIN_AUR_CACHE:-$HOME/.cache/tanin-aur}"
PUBLISH="${TANIN_PUBLISH_CMD:-}"

# AUR-only deps of TANINUX (not in the official repos). Mirrors the list in
# finish-tanin-repo.sh — keep them in sync.
AUR_PKGS=(eww-git tiramisu-git waypaper calamares librewolf-bin
          arch-update timeshift-autosnap xdg-terminal-exec paru)

log() { printf '[%s] %s\n' "$REPO_NAME-aur" "$*"; }

# --- one-time setup --------------------------------------------------------
setup() {
  sudo pacman -S --needed --noconfirm devtools git jq curl
  mkdir -p "$CHROOT" "$CACHE" "$OUT"
  if [ ! -d "$CHROOT/root" ]; then
    log "creating clean chroot at $CHROOT (base-devel) …"
    mkarchroot "$CHROOT/root" base-devel
  else
    log "chroot already present at $CHROOT"
  fi
  log "setup done."
}

# latest AUR version (ver-rel, may include epoch) via the RPC; empty on failure.
aur_version() {
  curl -fsSL "https://aur.archlinux.org/rpc/v5/info?arg%5B%5D=$1" 2>/dev/null \
    | jq -r '.results[0].Version // empty' 2>/dev/null
}

# best-effort version of the newest built package file in a dir (ver-rel).
built_version() {
  local f; f="$(ls -t "$1"/*.pkg.tar.zst 2>/dev/null | head -1)" || return 1
  [ -n "$f" ] || return 1
  basename "$f" | sed -E 's/.*-([^-]+-[0-9]+)-[^-]+\.pkg\.tar\.zst$/\1/'
}

# decide whether $1 needs a rebuild. -git: always. others: AUR ver != last built.
should_build() {
  local p="$1"
  [[ "$p" == *-git ]] && return 0
  local rpc; rpc="$(aur_version "$p")"
  [ -z "$rpc" ] && return 0                      # RPC down → build to be safe
  local last; last="$(cat "$CACHE/$p.ver" 2>/dev/null || echo)"
  [ "$rpc" != "$last" ]
}

# fetch/refresh the AUR PKGBUILD repo for $1 into the cache.
fetch() {
  local p="$1" dir="$CACHE/$p"
  if [ -d "$dir/.git" ]; then
    git -C "$dir" pull -q --ff-only 2>/dev/null || { rm -rf "$dir"; }
  fi
  [ -d "$dir/.git" ] || git clone -q "https://aur.archlinux.org/$p.git" "$dir"
}

# build $1 in the clean chroot and copy results into the repo dir.
build_one() {
  local p="$1" dir="$CACHE/$p"
  fetch "$p" || { log "FETCH FAILED: $p"; return 1; }
  if ! should_build "$p"; then
    log "up to date: $p"
    return 2
  fi
  log "building: $p"
  rm -f "$dir"/*.pkg.tar.zst
  # -c = clean copy of the chroot each time; -r = which chroot; -- = makepkg args
  if ( cd "$dir" && makechrootpkg -c -r "$CHROOT" -- --noconfirm ); then
    cp "$dir"/*.pkg.tar.zst "$OUT"/ && log "   ok: $p"
    built_version "$dir" > "$CACHE/$p.ver" 2>/dev/null || true
    return 0
  fi
  log "   BUILD FAILED: $p"
  return 1
}

run() {
  [ -d "$CHROOT/root" ] || { log "no chroot — run '$0 setup' first"; exit 1; }
  mkdir -p "$OUT" "$CACHE"
  local built=0 failed=0
  for p in "${AUR_PKGS[@]}"; do
    build_one "$p"; case $? in 0) built=$((built+1));; 1) failed=$((failed+1));; esac
  done

  if [ "$built" -gt 0 ]; then
    log "refreshing DB ($built rebuilt)"
    repo-add -q "$DB" "$OUT"/*.pkg.tar.zst >/dev/null
    # keep only the newest file per package on disk
    command -v paccache >/dev/null && paccache -rq -k1 -c "$OUT" >/dev/null 2>&1 || true
    if [ -n "$PUBLISH" ]; then
      log "publishing via TANIN_PUBLISH_CMD"
      eval "$PUBLISH" || log "PUBLISH FAILED"
    else
      log "no TANIN_PUBLISH_CMD set — local repo only (hosting not wired yet)"
    fi
  else
    log "nothing rebuilt — DB untouched"
  fi
  log "done (rebuilt=$built failed=$failed)"
  [ "$failed" -eq 0 ]
}

status() {
  for p in "${AUR_PKGS[@]}"; do
    if [[ "$p" == *-git ]]; then
      printf '%-22s -git → always rebuild\n' "$p"
    else
      local rpc last; rpc="$(aur_version "$p")"; last="$(cat "$CACHE/$p.ver" 2>/dev/null || echo -)"
      printf '%-22s aur=%-16s built=%-16s %s\n' "$p" "${rpc:-?}" "$last" \
        "$([ "$rpc" != "$last" ] && echo '→ REBUILD' || echo 'up-to-date')"
    fi
  done
}

case "${1:-run}" in
  setup)  setup ;;
  run)    run ;;
  status) status ;;
  *) echo "usage: $0 {setup|run|status}" >&2; exit 2 ;;
esac