#!/bin/bash
#
# SPDX-FileCopyrightText: 2023 David Runge <dave@sleepmap.de>
# SPDX-License-Identifier: LGPL-3.0-or-later
#
# This post-install handler adjusts labels and UUIDs after updating.
# It applies to scenarios in which btrfs is used as root filesystem, which can only be handled using a RAUC slot type "raw".
# The modifications for btrfs are necessary, as otherwise two partitions will potentially have the same UUIDs after
# update, which leads to a filesystem error upon reboot (btrfs generation error).

set -eu

printf "Adjusting partitions after installation of update...\n"

for i in $RAUC_TARGET_SLOTS; do
  eval RAUC_SLOT_DEVICE=\$"RAUC_SLOT_DEVICE_${i}"
  eval RAUC_SLOT_BOOTNAME=\$"RAUC_SLOT_BOOTNAME_${i}"
  eval RAUC_SLOT_CLASS=\$"RAUC_SLOT_CLASS_${i}"
  eval RAUC_SLOT_TYPE=\$"RAUC_SLOT_TYPE_${i}"

  case $RAUC_SLOT_BOOTNAME in
    system0)
      if [[ "$RAUC_SLOT_TYPE" == raw ]]; then
        printf "Set new (random) UUID for updated raw (btrfs) partition %s\n" "$RAUC_SLOT_DEVICE"
        btrfstune -fu "$RAUC_SLOT_DEVICE"
      fi

      case $RAUC_SLOT_CLASS in
        efi)
          printf "Set new label for updated EFI partition %s\n" "$RAUC_SLOT_DEVICE"
          fatlabel "$RAUC_SLOT_DEVICE" 'ESP_A' 
        ;;
        rootfs)
          printf "Set new label for updated (btrfs) rootfs partition %s\n" "$RAUC_SLOT_DEVICE"
          btrfs filesystem label "$RAUC_SLOT_DEVICE" 'root_b'
        ;;
      esac
    ;;
    system1)
      if [[ "$RAUC_SLOT_TYPE" == raw ]]; then
        printf "Set new (random) UUID for updated raw (btrfs) partition %s\n" "$RAUC_SLOT_DEVICE"
        btrfstune -fu "$RAUC_SLOT_DEVICE"
      fi

      case $RAUC_SLOT_CLASS in
        efi)
          printf "Set new label for updated EFI partition %s\n" "$RAUC_SLOT_DEVICE"
          fatlabel "$RAUC_SLOT_DEVICE" 'ESP_B' 
        ;;
        rootfs)
          printf "Set new label for updated (btrfs) rootfs partition %s\n" "$RAUC_SLOT_DEVICE"
          btrfs filesystem label "$RAUC_SLOT_DEVICE" 'root_b'
        ;;
      esac
    ;;
  esac
done