#!/usr/bin/env bash

# https://www.dynu.com/DynamicDNS/IPUpdateClient/cURL

#### OPTIONS

set -o errexit -o pipefail

#### DEFINITIONS

PROG=$(basename "${0}")
DDNS_USERNAME="${DDNS_USERNAME:-}"
DDNS_PASSWORD="${DDNS_PASSWORD:-}"
DDNS_HOSTNAME="${DDNS_HOSTNAME:-}"
DDNS_ALIAS="${DDNS_ALIAS:-}"
IPV4="${DDNS_IPV4:-auto}"
IPV6="${DDNS_IPV6:-no}"

#### FUNCTIONS

## Function to throw an error
function throw_error() {
  local error_input="${1}"
  printf "[ERROR]: %s\n" "${error_input}" >&2
  exit 1
}

function is_installed(){
  local input="${1}"
  if ! command -v "${input}" >/dev/null 2>&1; then
    throw_error "Cannot find '${input}' in PATH. Please make sure '${input}' is installed and is in your PATH"
  fi
}


#### MAIN

is_installed "curl"
curl                                         \
  --location                                 \
  --user "${DDNS_USERNAME}:${DDNS_PASSWORD}" \
  "https://api.dynu.com/nic/update?hostname=${DDNS_HOSTNAME}&myip=${IPV4}&myipv6=${IPV6}"