#!/bin/bash

# Path to Nginx configuration file
NGINX_CONFIG="/etc/nginx/vhosts.d/dougal.conf"

# Extract the first hostname matching 'lan.dougal' from the config
# Assumes server_name lines like: server_name hostname1 hostname2;
HOSTNAME=$(grep -oE '[a-zA-Z0-9.-]*lan\.dougal[a-zA-Z0-9.-]*' "$NGINX_CONFIG" | head -n 1)

if [ -z "$HOSTNAME" ]; then
  echo "Error: No matching hostname found in $NGINX_CONFIG"
  exit 1
fi

# Path to IP retrieval script
IP_SCRIPT="$HOME/software/sbin/get-ip.sh"

# Get the current IPv4 address
IP_ADDRESS=$("$IP_SCRIPT" |head -n1)

if [ -z "$IP_ADDRESS" ]; then
  echo "Error: Failed to retrieve IP address from $IP_SCRIPT"
  exit 1
fi

# Check for DYNDNS_PASSWD environment variable
if [ -z "$DYNDNS_PASSWD" ]; then
  echo "Error: DYNDNS_PASSWD environment variable is not set"
  exit 1
fi

# Hurricane Electric DynDNS update URL
UPDATE_URL="https://dyn.dns.he.net/nic/update?hostname=$HOSTNAME&password=$DYNDNS_PASSWD&myip=$IP_ADDRESS"

# Send the update request and capture the response
RESPONSE=$(curl -s "$UPDATE_URL")

# Output the response for logging/debugging
echo "Update response for $HOSTNAME ($IP_ADDRESS): $RESPONSE"