// Pure helpers: choose which URL a service tile opens, based on whether the dashboard
// is being viewed on-network (LAN) or remotely. No DOM / no network access here.

const PRIVATE_RE = /^(localhost$|127\.|10\.|192\.168\.|172\.(1[6-9]|2\d|3[01])\.)/;

// True when `hostname` is NOT a private/local address — i.e. the dashboard is being
// accessed remotely (e.g. via void.hynesy.com).
export function isRemoteHost(hostname = '') {
  const h = String(hostname).toLowerCase();
  if (!h) return false;
  if (PRIVATE_RE.test(h)) return false;
  if (h.endsWith('.local') || h.endsWith('.lan')) return false;
  if (!h.includes('.')) return false;            // bare hostname (e.g. "ct311")
  return true;
}

// For a service ({ url, external }) and whether we're remote, return the primary URL
// the tile opens, an optional alt (the other URL) for one-click fallback, and whether
// the service is LAN-only while remote.
export function pickServiceUrls(svc = {}, remote = false) {
  const url = svc.url || '';
  const external = svc.external || '';
  let primary, alt;
  if (remote) { primary = external || url; alt = external ? url : ''; }
  else        { primary = url;             alt = external || ''; }
  if (alt && alt === primary) alt = '';
  return { primary, alt: alt || null, lanOnly: remote && !external };
}