#!/usr/bin/env bash

: "${ISCSIADM_HOST_STRATEGY:=chroot}"
: "${ISCSIADM_HOST_PATH:=iscsiadm}"

echoerr() { printf "%s\n" "$*" >&2; }

P="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/run/current-system/sw/bin"

case ${ISCSIADM_HOST_STRATEGY} in
  chroot)
    # https://www.docker.com/blog/road-to-containing-iscsi/

    if [[ "${ISCSIADM_HOST_PATH}" =~ ^\/ && -f "/host${ISCSIADM_HOST_PATH}" ]]; then
      chroot /host "${ISCSIADM_HOST_PATH}" "${@:1}"
      exit $?
    fi

    for p in $(echo $P | cut -d ":" -f 1- --output-delimiter=" "); do
      if [[ -f "/host${p}/iscsiadm" ]]; then
        chroot /host "${p}/iscsiadm" "${@:1}"
        exit $?
      fi
    done

    chroot /host /usr/bin/env -i PATH="${P}" ${ISCSIADM_HOST_PATH} "${@:1}"
    exit $?
    ;;

  nsenter)
    # https://github.com/siderolabs/extensions/issues/38#issuecomment-1125403043
    iscsid_pid=$(pgrep --exact --oldest iscsid)
    if [[ "${iscsid_pid}x" == "x" ]]; then
      echoerr "failed to find iscsid pid for nsenter"
      exit 1
    fi
    nsenter --mount="/proc/${iscsid_pid}/ns/mnt" --net="/proc/${iscsid_pid}/ns/net" -- ${ISCSIADM_HOST_PATH} "${@:1}"
    exit $?
    ;;

  *)
    echoerr "invalid ISCSIADM_HOST_STRATEGY: ${ISCSIADM_HOST_STRATEGY}"
    exit 1
    ;;
esac