#!/usr/bin/env bash

# CONSTANTS

BASEDIR=$(dirname "$0")
CONTAINER=''
USER=''

# FUNCTIONS

function usage {
	echo "$(basename "$0") <CONTAINER_NAME> [--user|-u USER]"
}

function parse_options {
	while [[ $# -gt 0 ]]; do
		case "$1" in
			--help | -h)
				usage && exit 0
				;;
			--user | -u)
				shift 1
				[[ -z ${1:-} ]] && >&2 echo 'ERROR: user expected!' && usage && exit 5
				USER="$1"
				;;
			*)
				if [[ -z $CONTAINER ]]; then
					CONTAINER=$1
				else
					echo >&2 "Unknown option: $1" && usage && exit 2
				fi
				;;
		esac

		shift 1 # Move to the next argument
	done
	[[ -n $CONTAINER ]] || (usage && exit 1)
}

function incus_su {
	incus exec "$CONTAINER" -- su - $1
}

function incus_user_exists {
	incus exec "$CONTAINER" -- id $1 &> /dev/null
}

function login {
	if [[ -n $USER ]]; then
		incus_su $USER
	else
		local current=$(whoami)
		incus_user_exists $current && incus_su $current || incus_su root
	fi
}

# MAIN

set -Eue
parse_options $*
login