#!/usr/bin/env bash
# Pin Dankserver's fleet NIC (eno1, 192.168.0.235) as the primary default route.
#
# The 2026-09-20 board swap (TUF GAMING B650-E -> ProArt B850-Creator WiFi NEO)
# brought up a second port, eno2, which took DHCP and — with NetworkManager's
# default per-connection metric of 100 — came up with metric 101 while eno1's
# static gateway got 102. Outbound traffic therefore started leaving by eno2
# even though every fleet peer, Caddy upstream and monitoring target addresses
# this host as .235. Keep eno2 (it is a real second link) but make it secondary:
# route metrics decide the default route, so eno1 wins while eno2 stays a
# failover.
#
# Run on Dankserver.  Idempotent; NetworkManager owns these connections (the
# netplan files under /etc/netplan are its generated shim, so edit via nmcli).
#
#   bash scripts/dankserver-route-primary.sh [--check]
set -euo pipefail

PRIMARY='Wired connection 1'      # eno1, static 192.168.0.235, fleet address
SECONDARY='Wired connection 2'    # eno2, DHCP 192.168.0.247
PRIMARY_IF='eno1'
SECONDARY_IF='eno2'
PRIMARY_METRIC=100
SECONDARY_METRIC=200

show() {
    printf 'routes:\n'; ip route show default
    printf 'wanted: %s metric %s, %s metric %s\n' \
        "$PRIMARY" "$PRIMARY_METRIC" "$SECONDARY" "$SECONDARY_METRIC"
}

if [[ "${1:-}" == '--check' ]]; then
    for conn in "$PRIMARY" "$SECONDARY"; do
        printf '%s: ipv4=%s ipv6=%s\n' "$conn" \
            "$(nmcli -g ipv4.route-metric connection show "$conn")" \
            "$(nmcli -g ipv6.route-metric connection show "$conn")"
    done
    show
    exit 0
fi

nmcli connection modify "$PRIMARY" \
    ipv4.route-metric "$PRIMARY_METRIC" ipv6.route-metric "$PRIMARY_METRIC"
nmcli connection modify "$SECONDARY" \
    ipv4.route-metric "$SECONDARY_METRIC" ipv6.route-metric "$SECONDARY_METRIC"

# `nmcli device reapply <ifname>` pushes the edited profile without tearing the
# link down.  `nmcli connection up` would re-run DHCP and briefly drop the route
# this session rides on, and `connection reapply` is not a verb (NM 1.54).
nmcli device reapply "$PRIMARY_IF"
nmcli device reapply "$SECONDARY_IF"

show
if [[ "$(ip route show default | head -1)" != *"dev $PRIMARY_IF"* ]]; then
    printf 'ERROR: eno1 is still not the preferred default route\n' >&2
    exit 1
fi
printf 'eno1 is the preferred default route; eno2 remains up as failover.\n'