if test -e env/bin/activate
then
  . ./env/bin/activate
fi

if test -f pyproject.toml; then
  backend=$(sed -nr 's/^build-backend *= *\"([a-z]+).*/\1/p' pyproject.toml)
  case $backend in
    poetry|pdm|hatchling)
      backend_command=${backend%ling}
      if ! command -v $backend_command >/dev/null 2>&1; then
        echo WARNING: $backend_command is not installed, the Python environment will not be loaded >/dev/stderr
      else
        while IFS= read -r -d $'\0' pair; do
          export "$pair"
        done < <($backend_command run env -0)
      fi
      ;;
    ,*)
      echo "WARNING: Unsupported build backend '$backend', the Python environment will not be loaded" >/dev/stderr
  esac
fi