#!/bin/bash
set -e

echo ">>> [fix-bootentry] Running INSIDE target system"

ENTRYDIR="/boot/loader/entries"
[ -d "${ENTRYDIR}" ] || { echo ">>> [fix-bootentry] No ${ENTRYDIR}, skipping."; exit 0; }

ROOT_UUID="$(findmnt -no UUID / || true)"
if [ -z "${ROOT_UUID}" ]; then
  ROOT_UUID="$(awk '$2 == "/" && $1 ~ /^UUID=/ {print $1; exit}' /etc/fstab | sed 's/^UUID=//')"
fi

if [ -z "${ROOT_UUID}" ]; then
  echo ">>> [fix-bootentry] Could not determine root UUID, leaving entries untouched."
  exit 0
fi

SWAP_UUID="$(awk '$3 == "swap" && $1 ~ /^UUID=/ {print $1; exit}' /etc/fstab | sed 's/^UUID=//')"
ROOT_OPTS="$(awk '$2 == "/" {print $4; exit}' /etc/fstab)"
SUBVOL="$(echo "$ROOT_OPTS" | tr ',' '\n' | grep '^subvol=' | head -1 || true)"

echo ">>> [fix-bootentry] root UUID: ${ROOT_UUID} | swap UUID: ${SWAP_UUID:-nincs} | subvol: ${SUBVOL:-nincs}"

for f in "${ENTRYDIR}"/*.conf; do
  [ -f "$f" ] || continue
  grep -qE '^options[[:space:]]' "$f" || continue

  if grep -qE '^options[[:space:]].*\broot=' "$f"; then
    sed -i -E "s#root=[^[:space:]]*#root=UUID=${ROOT_UUID}#" "$f"
  else
    sed -i -E "s#^options[[:space:]]+#options root=UUID=${ROOT_UUID} #" "$f"
  fi

  if [ -n "${SWAP_UUID}" ]; then
    if grep -qE '\bresume=' "$f"; then
      sed -i -E "s#resume=[^[:space:]]*#resume=UUID=${SWAP_UUID}#" "$f"
    else
      sed -i -E "s#^(options[[:space:]].*)#\1 resume=UUID=${SWAP_UUID}#" "$f"
    fi
  else
    sed -i -E "s#[[:space:]]+resume=[^[:space:]]*##g" "$f"
  fi

  if [ -n "${SUBVOL}" ]; then
    if grep -qE '\brootflags=subvol=' "$f"; then
      sed -i -E "s#rootflags=subvol=[^[:space:]]*#rootflags=${SUBVOL}#" "$f"
    else
      sed -i -E "s#^(options[[:space:]].*)#\1 rootflags=${SUBVOL}#" "$f"
    fi
  fi

  echo ">>> [fix-bootentry] Fixed: $f"
done

echo ">>> [fix-bootentry] Done."
exit 0