#!/bin/bash

if mount | grep -q "on / type aufs"; then
    cat <<EOF >&2
WARNING: Generation of wic images will fail!

Your docker host setup uses broken aufs as storage driver. Adjust the docker
configuration to use a different driver (overlay, overlay2, devicemapper). You
may also need to update the host distribution (e.g. Debian Jessie -> Stretch).

EOF
fi

USER_ID=${USER_ID:-30000}
GROUP_ID=${GROUP_ID:-30000}

if [ $USER_ID == 0 ]; then
	# We shall run everything as root
	mkdir -p /builder

	GOSU=""
elif [ $USER_ID == $UID ]; then
	GOSU=""
else
	if ! grep -q "^builder:" /etc/group; then
		groupadd -o --gid $GROUP_ID builder
	fi
	if ! id builder >/dev/null 2>&1; then
		# Create a non-root user that will perform the actual build
		useradd -o --uid $USER_ID --gid $GROUP_ID --create-home \
			--home-dir /builder builder
	fi

	GOSU="gosu builder"
fi

if [ "$PWD" = / ]; then
	cd /builder
fi

if [ -n "$1" ]; then
	case "$1" in
	build|checkout|for-all-repos|menu|shell|-*)
		exec $GOSU kas "$@"
		;;
	*)
		exec $GOSU "$@"
		;;
	esac
else
	exec $GOSU bash
fi