#!/usr/bin/env bash
set -e

# ============================
# CONFIG
# ============================
HEADSCALE_URL="https://headscale.rozic-dev.com"
TAILSCALE_BIN="tailscale"
DEFAULT_HOSTNAME="$(hostname)"

require_cmd() {
  if ! command -v "$1" >/dev/null 2>&1; then
    echo "ERROR: Command '$1' not found. Please install it first." >&2
    exit 1
  fi
}

require_cmd "$TAILSCALE_BIN"

if ! command -v sudo >/dev/null 2>&1 && [[ $EUID -ne 0 ]]; then
  echo "WARNING: 'sudo' not found and you are not root."
  echo "You must run this script as root for 'tailscale up' to work."
  exit 1
fi

AUTHKEY="${1:-}"

if [[ -z "$AUTHKEY" ]]; then
  echo -n "Enter Headscale pre-auth key: "
  read -r AUTHKEY
fi

if [[ -z "$AUTHKEY" ]]; then
  echo "ERROR: No auth key provided." >&2
  exit 1
fi

echo -n "Hostname to register on Headscale [${DEFAULT_HOSTNAME}]: "
read -r CUSTOM_HOSTNAME
HOSTNAME_TO_USE="${CUSTOM_HOSTNAME:-$DEFAULT_HOSTNAME}"

echo
echo "Connecting this device to Headscale:"
echo "  Server : ${HEADSCALE_URL}"
echo "  Host   : ${HOSTNAME_TO_USE}"
echo

TS_CMD=(
  "$TAILSCALE_BIN" up
  --reset
  --login-server="${HEADSCALE_URL}"
  --auth-key="${AUTHKEY}"
  --hostname="${HOSTNAME_TO_USE}"
)

if [[ $EUID -ne 0 ]]; then
  echo "Running: sudo ${TS_CMD[*]}"
  sudo "${TS_CMD[@]}"
else
  echo "Running: ${TS_CMD[*]}"
  "${TS_CMD[@]}"
fi

echo
echo "✅ Done! This device should now be visible in Headscale."