// Simple hash-based SPA router
const routes = {};
let currentCleanup = null;

export function route(path, handler) {
  routes[path] = handler;
}

export function navigate(path) {
  window.location.hash = path;
}

export function currentPath() {
  return window.location.hash.slice(1) || '/';
}

export function getParam(name) {
  const path = currentPath();
  // Match patterns like /services/:id
  for (const pattern of Object.keys(routes)) {
    const paramNames = [];
    const regex = pattern.replace(/:(\w+)/g, (_, name) => {
      paramNames.push(name);
      return '([^/]+)';
    });
    const match = path.match(new RegExp(`^${regex}$`));
    if (match) {
      const idx = paramNames.indexOf(name);
      if (idx >= 0) return match[idx + 1];
    }
  }
  return null;
}

export function startRouter(container) {
  function handleRoute() {
    const path = currentPath();

    // Cleanup previous page
    if (currentCleanup) { currentCleanup(); currentCleanup = null; }

    // Find matching route
    for (const [pattern, handler] of Object.entries(routes)) {
      const paramNames = [];
      const regex = pattern.replace(/:(\w+)/g, (_, n) => { paramNames.push(n); return '([^/]+)'; });
      const match = path.match(new RegExp(`^${regex}$`));
      if (match) {
        const params = {};
        paramNames.forEach((n, i) => params[n] = match[i + 1]);
        const cleanup = handler(container, params);
        if (typeof cleanup === 'function') currentCleanup = cleanup;
        updateActiveLink(path);
        return;
      }
    }

    // Default: redirect to /
    navigate('/');
  }

  window.addEventListener('hashchange', handleRoute);
  handleRoute();
}

function updateActiveLink(path) {
  document.querySelectorAll('.sidebar-link[data-path]').forEach(el => {
    const linkPath = el.dataset.path;
    if (linkPath === '/') {
      el.classList.toggle('active', path === '/');
    } else {
      el.classList.toggle('active', path.startsWith(linkPath));
    }
  });
}