#!/usr/bin/env bash
#
# Summary: Uninstall a specific Python virtualenv
#
# Usage: pyenv virtualenv-delete [-f|--force] <virtualenv>
#
#    -f  Attempt to remove the specified virtualenv without prompting
#        for confirmation. If the virtualenv does not exist, do not
#        display an error message.
#
# See `pyenv virtualenvs` for a complete list of installed versions.
#
set -e
[ -n "$PYENV_DEBUG" ] && set -x

if [ -z "${PYENV_ROOT}" ]; then
  PYENV_ROOT="$(pyenv-root)"
fi

# Provide pyenv completions
if [ "$1" = "--complete" ]; then
  exec pyenv virtualenvs --bare
fi

resolve_link() {
  $(type -p greadlink readlink | head -1) "$1"
}

usage() {
  pyenv-help virtualenv-delete 2>/dev/null
  [ -z "$1" ] || exit "$1"
}

if [ -z "$PYENV_ROOT" ]; then
  PYENV_ROOT="${HOME}/.pyenv"
fi

if [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
  usage 0
fi

unset FORCE
if [ "$1" = "-f" ] || [ "$1" = "--force" ]; then
  FORCE=true
  shift
fi

[ "$#" -eq 1 ] || usage 1 >&2

DEFINITION="$1"
case "$DEFINITION" in
"" | -* )
  usage 1 >&2
  ;;
esac

VERSION_NAME="${DEFINITION##*/}"
COMPAT_PREFIX="${PYENV_ROOT}/versions/${VERSION_NAME}"

if [[ "${DEFINITION}" != "${DEFINITION%/envs/*}" ]]; then
  PREFIX="${PYENV_ROOT}/versions/${DEFINITION}"
  if [ -L "${COMPAT_PREFIX}" ]; then
    if [[ "${PREFIX}" != "$(resolve_link "${COMPAT_PREFIX}" 2>/dev/null || true)" ]]; then
      unset COMPAT_PREFIX
    fi
  fi
else
  if [ -L "${COMPAT_PREFIX}" ]; then
    PREFIX="$(resolve_link "${COMPAT_PREFIX}" 2>/dev/null || true)"
    if [[ "${PREFIX%/*/envs/*}" != "${PYENV_ROOT}/versions" ]]; then
      echo "pyenv-virtualenv: \`${COMPAT_PREFIX}' is a symlink for unknown location." 1>&2
      exit 1
    fi
  else
    if pyenv-virtualenv-prefix "${VERSION_NAME}" 1>/dev/null 2>&1; then
      PREFIX="${PYENV_ROOT}/versions/${VERSION_NAME}"
      unset COMPAT_PREFIX
    elif [ -z "$FORCE" ]; then
      echo "pyenv-virtualenv: \`${DEFINITION}' is not a virtualenv." 1>&2
      exit 1
    fi
  fi
fi

if [ -z "$FORCE" ]; then
  if [ ! -d "$PREFIX" ]; then
    echo "pyenv-virtualenv: virtualenv \`$VERSION_NAME' not installed" >&2
    exit 1
  fi

  read -p "pyenv-virtualenv: remove $PREFIX? (y/N) "
  case "$REPLY" in
  y* | Y* ) ;;
  * ) exit 1 ;;
  esac
fi

if [ -d "$PREFIX" ]; then
  rm -rf "$PREFIX"
  if [ -L "$COMPAT_PREFIX" ]; then
    rm -rf "$COMPAT_PREFIX"
  fi
  pyenv-rehash
fi