set -o errexit
set -o nounset
set -o pipefail
shopt -s lastpipe

MACHINE=""
HOSTFWD=""

while getopts 'p:o:h' opt; do
  case "$opt" in
  p)
    HOSTFWD=",hostfwd=tcp::$OPTARG$HOSTFWD"
    ;;

  o)
    MACHINE="$OPTARG"
    ;;

  h | ?)
    echo "Usage: $(basename "$0") [-p hostport-:guestport] -o MACHINE"
    exit 1
    ;;
  esac
done
shift "$((OPTIND - 1))"

if [ -z "$MACHINE" ]; then
  echo "-o option needed"
  exit 1
fi

DRV_PATH=$(colmena eval --instantiate -E "{nodes, ...}: nodes.$MACHINE.config.system.build.vm")

echo "Realising $DRV_PATH"
RESULT=$(nix-store -r "$DRV_PATH")

echo "Built $RESULT, launching VM ..."

"$RESULT/bin/run-$MACHINE-vm" -device e1000,netdev=net0 -netdev "user,id=net0$HOSTFWD"