#!/bin/bash

# mount.sh - Mount a disk image with btrfs subvolumes (CI mode compatible)

# Usage: ./mount.sh <image_file> [mount_point]

set -e

if [ "$EUID" -ne 0 ]; then

echo "Error: This script must be run as root"

exit 1

fi

if [ -z "$1" ]; then

echo "Usage: $0 <image_file> [mount_point]"

echo "Example: $0 img.img /mnt"

exit 1

fi

IMAGE_FILE="$1"

MOUNT_POINT="${2:-/mnt/img}"

if [ ! -f "$IMAGE_FILE" ]; then

echo "Error: Image file '$IMAGE_FILE' not found"

exit 1

fi

echo "==> Attaching image to loop device..."

LOOP_DEV=$(losetup -f)

losetup -P "$LOOP_DEV" "$IMAGE_FILE"

echo " Loop device: $LOOP_DEV"

echo "==> Creating device mapper symlink (CI mode)..."

MAPPER_DEV="/dev/mapper/$(basename $LOOP_DEV)"

ln -sf "$LOOP_DEV" "$MAPPER_DEV"

echo "==> Creating partition mappings with kpartx..."

kpartx -avf "$LOOP_DEV"

sleep 1 # Give udev time to create devices

# In CI mode, partitions are available as /dev/mapper/loopXpY

ROOT_PART="${MAPPER_DEV}p3"

if [ ! -b "$ROOT_PART" ]; then

echo "Error: Root partition $ROOT_PART not found"

echo "Available devices:"

ls -la /dev/mapper/

kpartx -d "$LOOP_DEV"

losetup -d "$LOOP_DEV"

unlink "$MAPPER_DEV" 2>/dev/null || true

exit 1

fi

echo "==> Creating mount point: $MOUNT_POINT"

mkdir -p "$MOUNT_POINT"

echo "==> Mounting root subvolume (@) from $ROOT_PART..."

mount -t btrfs -o compress=zstd,subvol=/@ "$ROOT_PART" "$MOUNT_POINT"

echo "==> Creating subdirectories..."

mkdir -p "$MOUNT_POINT/home"

mkdir -p "$MOUNT_POINT/var/log"

mkdir -p "$MOUNT_POINT/var/cache/pacman/pkg"

mkdir -p "$MOUNT_POINT/.snapshots"

echo "==> Mounting btrfs subvolumes..."

mount -t btrfs -o compress=zstd,subvol=/@home "$ROOT_PART" "$MOUNT_POINT/home"

mount -t btrfs -o compress=zstd,subvol=/@log "$ROOT_PART" "$MOUNT_POINT/var/log"

mount -t btrfs -o compress=zstd,subvol=/@pkg "$ROOT_PART" "$MOUNT_POINT/var/cache/pacman/pkg"

mount -t btrfs -o compress=zstd,subvol=/@.snapshots "$ROOT_PART" "$MOUNT_POINT/.snapshots"

echo ""

echo "==> Successfully mounted image!"

echo " Image: $IMAGE_FILE"

echo " Loop device: $LOOP_DEV"

echo " Root part: $ROOT_PART"

echo " Mount point: $MOUNT_POINT"

echo ""

echo "Mount layout:"

lsblk "$LOOP_DEV"

echo ""

echo "To unmount, run: umount -R $MOUNT_POINT && kpartx -d $LOOP_DEV && losetup -d $LOOP_DEV && unlink $MAPPER_DEV"