#!/usr/bin/env bash
#
# Summary: Display real_prefix for a Python virtualenv version
# Usage: pyenv virtualenv-prefix [<virtualenv>]
#

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

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

if [ -n "$1" ]; then
  versions=($@)
  IFS=: PYENV_VERSION="${versions[*]}"
  export PYENV_VERSION
else
  IFS=: versions=($(pyenv-version-name))
fi

VIRTUALENV_PREFIX_PATHS=()
for version in "${versions[@]}"; do
  if [ "$version" = "system" ]; then
    echo "pyenv-virtualenv: version \`${version}' is not a virtualenv" 1>&2
    exit 1
  fi
  PYENV_PREFIX_PATH="$(pyenv-prefix "${version}")"
  if [ -x "${PYENV_PREFIX_PATH}/bin/python" ]; then
    if [ -f "${PYENV_PREFIX_PATH}/bin/activate" ]; then
      if [ -f "${PYENV_PREFIX_PATH}/bin/conda" ]; then
        # conda
        VIRTUALENV_PREFIX_PATH="${PYENV_PREFIX_PATH}"
      else
        if [ -f "${PYENV_ROOT}/versions/${version}/pyvenv.cfg" ]; then
          # pyvenv
          virtualenv_binpath="$(cut -b 1-1024 "${PYENV_ROOT}/versions/${version}/pyvenv.cfg" | sed -n '/^ *home *= */s///p' || true)"
          VIRTUALENV_PREFIX_PATH="${virtualenv_binpath%/bin}"
        else
          # virtualenv
          shopt -s nullglob
          VIRTUALENV_PREFIX_PATH="$(cat "${PYENV_ROOT}/versions/${version}/lib/"*"/orig-prefix.txt" </dev/null 2>&1 || true)"
          shopt -u nullglob
        fi
      fi
      if [ -d "${VIRTUALENV_PREFIX_PATH}" ]; then
        VIRTUALENV_PREFIX_PATHS=("${VIRTUALENV_PREFIX_PATHS[@]}" "${VIRTUALENV_PREFIX_PATH:-${PYENV_PREFIX_PATH}}")
      else
        echo "pyenv-virtualenv: version \`${version}' is not a virtualenv" 1>&2
        exit 1
      fi
    else
      echo "pyenv-virtualenv: version \`${version}' is not a virtualenv" 1>&2
      exit 1
    fi
  else
    echo "pyenv-virtualenv: \`python' not found in version \`${version}'" 1>&2
    exit 1
  fi
done

IFS=: echo "${VIRTUALENV_PREFIX_PATHS[*]}"