#!/bin/bash
# Set hostname from DHCP lease
# Runs before k3s-agent to ensure proper node name

set -euo pipefail

log() { echo "[hostname] $*"; logger -t set-hostname "$*"; }

# Wait for DHCP lease
MAX_WAIT=60
for i in $(seq 1 $MAX_WAIT); do
    # Check for lease files from systemd-networkd
    for lease in /run/systemd/netif/leases/*; do
        if [ -f "$lease" ]; then
            HOSTNAME=$(grep -oP '^HOSTNAME=\K.*' "$lease" 2>/dev/null || true)
            if [ -n "$HOSTNAME" ]; then
                log "Found hostname in DHCP lease: $HOSTNAME"
                hostnamectl set-hostname "$HOSTNAME"
                log "Hostname set to: $(hostname)"
                exit 0
            fi
        fi
    done
    sleep 1
done

log "Warning: No DHCP hostname found after ${MAX_WAIT}s, using default"
exit 0