#!/usr/bin/env bash
# Summary: Configure the shell environment for pyenv-virtualenv
# Usage: eval "$(pyenv virtualenv-init - [<shell>])"
#
# Automatically activates a Python virtualenv environment based on current
# pyenv version.
#

set -e
[ -n "$PYENV_DEBUG" ] && set -x

print=""
for args in "$@"
do
  if [ "$args" = "-" ]; then
    print=1
    shift
  fi
done

shell="$1"
if [ -z "$shell" ]; then
  shell="$(ps c -p "$PPID" -o 'ucomm=' 2>/dev/null || true)"
  shell="${shell##-}"
  shell="${shell%% *}"
  shell="$(basename "${shell:-$SHELL}")"
fi

if [ -z "$print" ]; then
  case "$shell" in
  bash )
    profile='~/.bash_profile'
    ;;
  zsh )
    profile='~/.zshrc'
    ;;
  ksh )
    profile='~/.profile'
    ;;
  fish )
    profile='~/.config/fish/config.fish'
    ;;
  * )
    profile='your profile'
    ;;
  esac

  { echo "# Load pyenv-virtualenv automatically by adding"
    echo "# the following to ${profile}:"
    echo
    case "$shell" in
    fish )
      echo 'status --is-interactive; and . (pyenv virtualenv-init -|psub)'
      ;;
    * )
      echo 'eval "$(pyenv virtualenv-init -)"'
      ;;
    esac
    echo
  } >&2

  exit 1
fi

case "$shell" in
bash )
  cat <<EOS
export PYENV_VIRTUALENV_INIT=1
_pyenv_virtualenv_hook() {
  if [[ "\$(pyenv version-name)" == "system" ]]; then
    pyenv deactivate || true;
  elif [[ "\$VIRTUAL_ENV" != "\$(pyenv prefix)" ]]; then
    pyenv deactivate || true;
    pyenv activate 2>/dev/null || true
  fi
};
if ! [[ "\$PROMPT_COMMAND" =~ _pyenv_virtualenv_hook ]]; then
  PROMPT_COMMAND="_pyenv_virtualenv_hook;\$PROMPT_COMMAND";
fi
EOS
  ;;
fish )
  cat <<EOS
setenv PYENV_VIRTUALENV_INIT 1;
function _pyenv_virtualenv_hook --on-event fish_prompt;
  if [ (pyenv version-name) = "system" ]
    eval (pyenv sh-deactivate); or true
  else if [ "\$VIRTUAL_ENV" != (pyenv prefix) ]
    eval (pyenv sh-deactivate); or true
    eval (pyenv sh-activate 2>/dev/null); or true
  end
end
EOS
  ;;
zsh )
  cat <<EOS
export PYENV_VIRTUALENV_INIT=1
_pyenv_virtualenv_hook() {
  if [[ "\$(pyenv version-name)" == "system" ]]; then
    pyenv deactivate || true
  elif [[ "\$VIRTUAL_ENV" != "\$(pyenv prefix)" ]]; then
    pyenv deactivate || true
    pyenv activate 2>/dev/null || true
  fi
}
typeset -a precmd_functions
if [[ -z \$precmd_functions[(r)_pyenv_virtualenv_hook] ]]; then
  precmd_functions+=_pyenv_virtualenv_hook;
fi
EOS
  ;;
* )
  # FIXME: what should i do here??
  ;;
esac