#!/bin/bash

if [ "$#" -lt 3 ]; then
    echo "Usage: $0 <group> [subcommand] [options] -- /backup/..."
    exit 1
fi

# Check "end of options" delimiter

delimiter_arg="${@: -2:1}"

if [[ "$delimiter_arg" != -- ]]; then
    echo "Error: 'end of options' delimiter missing."
    exit 1
fi

# Check path

path_arg="${@: -1:1}"

if ! path=$(realpath --canonicalize-existing "$path_arg"); then
    echo "Error: Could not resolve the path '$path_arg'."
    exit 1
fi

if [[ "$path" != /backup* ]]; then
    echo "Error: The resolved path '$path' does not start with '/backup'."
    exit 1
fi

exec sudo /usr/sbin/btrfs "$@"
