#!/usr/bin/env bash
#
# Homelab monitoring, Part 6: Internet traffic with pfSense
# https://www.zadran.net/guides/homelab-monitoring-6-internet-traffic-pfsense
# Generated from the guide, last updated 2026-10-13.
#
# NO WARRANTY. This script is provided as is. You are responsible for
# understanding what it does before running it, and for the consequences.
# Take a backup first. See https://www.zadran.net/disclaimer
#
# Destructive steps are left commented out on purpose -- uncomment them
# only once you have understood what they do.
#
# Where the guide writes a file with <<'EOF' and your values are in it,
# this script uses <<EOF so that they expand. Every other $, ` and \
# gets a backslash, so the rest comes out exactly as the guide shows it.

set -euo pipefail

# ---- Set these for your environment ----
# From Part 1
CTID='140'
# pfSense's IP in your LAN
PFSENSE_IP='192.168.1.1'
# pfSense: Interfaces -> Assignments
WAN_IF='igc0'
# pfSense: Interfaces -> Assignments
LAN_IF='igc1'
# Total size, not the amount to add
DISK_SIZE='100G'
# About 15 % below the disk size
RETENTION_SIZE='85GB'
# The speed you pay for
CONTRACT_DOWN='250'
# The speed you pay for
CONTRACT_UP='50'

pct exec ${CTID} -- df -h /
pct exec ${CTID} -- du -sh /var/lib/docker/volumes/monitoring_prometheus-data
pct exec ${CTID} -- bash -c "curl -s localhost:9090/api/v1/query --data-urlencode 'query=prometheus_tsdb_head_series' | grep -o '\"value\":\[[^]]*\]'"

pct resize ${CTID} rootfs ${DISK_SIZE}
pct exec ${CTID} -- df -h /

pct exec ${CTID} -- bash -c "cd /opt/monitoring && mkdir -p backup && cp compose.yaml backup/compose.yaml.\$(date +%Y%m%d-%H%M%S) && (grep -q retention.size compose.yaml || sed -i 's|^\(\s*\)- --storage.tsdb.retention.time=\(.*\)$|&\n\1- --storage.tsdb.retention.size=${RETENTION_SIZE}|' compose.yaml) && grep -n retention compose.yaml && docker compose up -d prometheus"
pct exec ${CTID} -- bash -c "curl -s localhost:9090/api/v1/status/flags | grep -o '\"storage.tsdb.retention.[a-z]*\":\"[^\"]*\"'"

pct exec ${CTID} -- bash -c "cd /opt/monitoring && sed -i 's|retention.time=.*|retention.time=730d|' compose.yaml && docker compose up -d prometheus"

pct exec ${CTID} -- bash -c "curl -s --max-time 5 http://${PFSENSE_IP}:9100/metrics | grep -E '^node_network_(receive|transmit)_bytes_total\{device=\"(${WAN_IF}|${LAN_IF})\"'"

pct enter ${CTID}

P=/opt/monitoring/prometheus/prometheus.yml
cp $P /opt/monitoring/backup/prometheus.yml.$(date +%Y%m%d-%H%M%S)
cat >> $P <<EOF

  - job_name: pfsense
    static_configs:
      - targets: ['${PFSENSE_IP}:9100']
        labels:
          host: pfsense
    metric_relabel_configs:
      - source_labels: [device]
        regex: ${WAN_IF}
        target_label: iface
        replacement: WAN
      - source_labels: [device]
        regex: ${LAN_IF}
        target_label: iface
        replacement: LAN
EOF
docker exec prometheus promtool check config /etc/prometheus/prometheus.yml && curl -fsS -X POST localhost:9090/-/reload && echo reloaded

D=${CONTRACT_DOWN}; U=${CONTRACT_UP}
curl -fsSL https://www.zadran.net/downloads/grafana/dashboards/internet-pfsense.json | sed -e "s/777000000/$((D*1000000))/g; s/621600000/$((D*800000))/g; s/388500000/$((D*500000))/g; s/77000000/$((U*1000000))/g; s/61600000/$((U*800000))/g; s/38500000/$((U*500000))/g; s/777 Mbit/$D Mbit/g; s/77 Mbit/$U Mbit/g" > /opt/monitoring/grafana/provisioning/dashboards/files/Network/internet-pfsense.json
grep -c '"title"' /opt/monitoring/grafana/provisioning/dashboards/files/Network/internet-pfsense.json

cd /root
curl -fsSLO https://www.zadran.net/downloads/grafana/tools/vnstat2prom.py
T0=$(pct exec ${CTID} -- bash -c "curl -fsS -G localhost:9090/api/v1/query --data-urlencode 'query=min_over_time(timestamp(up{job=\"pfsense\"})[90d:5m])'" | grep -o '"value":\[[^]]*\]' | sed -E 's/.*,"([^"]+)"\]/\1/' | cut -d. -f1)
echo "Live pfSense data starts at: $(date -d @$T0)"
python3 vnstat2prom.py vnstat.json wan-history.om --iface ${WAN_IF} --until $T0

pct push ${CTID} wan-history.om /tmp/wan-history.om --perms 644
pct exec ${CTID} -- bash -c "docker cp /tmp/wan-history.om prometheus:/tmp/ && rm /tmp/wan-history.om"
pct exec ${CTID} -- docker exec prometheus sh -c 'promtool tsdb create-blocks-from openmetrics -q /tmp/wan-history.om /prometheus/backfill && mv /prometheus/backfill/* /prometheus/ && rmdir /prometheus/backfill'
pct exec ${CTID} -- docker restart prometheus
rm wan-history.om