automatically source venv using direnv

virtualenv_direnv.sh

# .envrc — prefer `workon py_env`, fallback to common venv locations
project_env='py_env'

# if workon is already available, use it
if type workon >/dev/null 2>&1; then
  workon "$project_env"
  return
fi

# try to source virtualenvwrapper to get workon
if [ -z "${VIRTUALENVWRAPPER_SCRIPT:-}" ]; then
  if [ -f "$HOME/.local/bin/virtualenvwrapper.sh" ]; then
    export VIRTUALENVWRAPPER_SCRIPT="$HOME/.local/bin/virtualenvwrapper.sh"
  elif [ -f "/usr/local/bin/virtualenvwrapper.sh" ]; then
    export VIRTUALENVWRAPPER_SCRIPT="/usr/local/bin/virtualenvwrapper.sh"
  fi
fi

if [ -n "${VIRTUALENVWRAPPER_SCRIPT:-}" ] && [ -f "$VIRTUALENVWRAPPER_SCRIPT" ]; then
  source "$VIRTUALENVWRAPPER_SCRIPT"
  if type workon >/dev/null 2>&1; then
    workon "$project_env"
    return
  fi
fi

# final fallback: add venv bin to PATH
if [ -d "./$project_env" ]; then
  export VIRTUAL_ENV="$PWD/$project_env"
  PATH_add "$VIRTUAL_ENV/bin"
elif [ -d "$HOME/.virtualenvs/$project_env" ]; then
  export VIRTUAL_ENV="$HOME/.virtualenvs/$project_env"
  PATH_add "$VIRTUAL_ENV/bin"
elif [ -d "./.venv" ]; then
  export VIRTUAL_ENV="$PWD/.venv"
  PATH_add "$VIRTUAL_ENV/bin"
else
  echo "direnv: virtualenv '$project_env' not found"
fi