#!/bin/sh

set -eu
umask 077

community="public"

mqtt_send() {
    topic="$1"
    value="$2"

    tlsdir="$(openssl version -d | sed -e 's/^OPENSSLDIR: "\(.\+\)"$/\1/')"
    mosquitto_pub -h mqtt02.home.foo.sh -t "$topic" -m "$value" \
        --cafile "${tlsdir}/certs/ca.crt" \
        --key "${tlsdir}/private/$(hostname -f).key" \
        --cert "${tlsdir}/certs/$(hostname -f).crt"
}

snmp_get() {
    host="$1"
    key="$2"
    snmpget -v 1 -c "$community" "$host" -Oqv -m MIKROTIK-MIB "$key" | tr -d '"'
}

# only run script if first vrrp interface is in master state
for state in /run/keepalived/*.state ; do
    if [ "$(cat "$state")" != "MASTER" ]; then
        exit 0
    fi
    break
done

ldapsearch -Q -LLL "(&(objectClass=device)(description=MikroTik *))" cn | \
    awk '{ if ($1 == "cn:") print $2 }' | while read -r name
do
    snmpwalk -v 1 -c "$community" "$name" -Oq -m MIKROTIK-MIB \
        MIKROTIK-MIB::mtxrPOEStatus | while read -r port status
    do
        port="$(echo "$port" | cut -d "." -f 2)"
        [ "$status" = "poweredOn" ] || continue

        device="$(snmp_get "$name" "SNMPv2-SMI::mib-2.31.1.1.1.18.${port}")"
        [ -z "$device" ] && continue
        location="$(ldapsearch -Q -LLL "(&(objectClass=device)(cn=${device}))" l | \
            sed -n 's/^l: \(.\+\)/\1/p' | tr '[:upper:]' '[:lower:]' | tr ' ' '_')"
        [ -z "$location" ] && continue

        for key in Current Power Voltage ; do
            topic="home/${location}/${device}/$(echo "$key" | tr '[:upper:]' '[:lower:]')"
            value="$(snmp_get "$name" "MIKROTIK-MIB::mtxrPOE${key}.${port}")"
            mqtt_send "$topic" "$value"
        done
    done
done