#!/bin/bash
# drac-extend: expose iDRAC IPMI temperature SDRs via snmpd extend [#625]
#
# Deployed to /usr/local/bin/drac-extend on pfv-tsys6 / pfv-tsys7.
# Creds live in /etc/snmp/drac-env (0600 root): DRAC_HOST, IPMI_USER, IPMI_PASS.
# Output: "<label> <celsius>" per enabled sensor, e.g. "inlet_temp 22".
# Consumed by Home Assistant SNMP sensors via value_template regex.
#
# Why extend and not the DRAC's own SNMP agent: iDRAC6/7 hardware MIB tables
# are unpopulated on this firmware generation (verified 2026-09-02), while
# IPMI SDR works. [#625]
set -euo pipefail

ENV_FILE="${DRAC_ENV:-/etc/snmp/drac-env}"
if [ ! -r "$ENV_FILE" ]; then
    echo "drac-extend: missing $ENV_FILE" >&2
    exit 1
fi
# shellcheck disable=SC1090  # env file is host-local by design (creds)
. "$ENV_FILE"
: "${DRAC_HOST:?DRAC_HOST unset}" "${IPMI_USER:?IPMI_USER unset}" "${IPMI_PASS:?IPMI_PASS unset}"
export IPMI_PASSWORD="${IPMI_PASS}"

ipmitool -I lanplus -E -H "$DRAC_HOST" -U "$IPMI_USER" \
    sdr type temperature 2>/dev/null |
    awk -F'|' '
        $3 ~ /ok/ && $5 ~ /degrees C/ {
            label = tolower($1)
            gsub(/[^a-z0-9]+/, "_", label)
            gsub(/^_+|_+$/, "", label)
            value = $5
            gsub(/[^0-9]/, "", value)
            print label, value
        }'