// Hash router. URLs are stable and shareable: the view, its filters, and paging
// all live in the hash, so a reload restores exactly what was on screen.
export function parseHash() {
  const raw = location.hash.slice(1) || "/workflow";
  const [path, queryString = ""] = raw.split("?");
  return { path, params: Object.fromEntries(new URLSearchParams(queryString)) };
}

export function navigate(path, params = {}) {
  const clean = Object.fromEntries(
    Object.entries(params).filter(([, v]) => v !== undefined && v !== null && v !== "")
  );
  const query = Object.keys(clean).length ? "?" + new URLSearchParams(clean) : "";
  location.hash = path + query;
}

export function onRouteChange(handler) {
  window.addEventListener("hashchange", handler);
  window.addEventListener("DOMContentLoaded", handler);
}