import type { V2NavItem } from '@/types/v2/nav'

/**
 * Pure helper — determines whether a V2NavItem is "active" given the current
 * route name.
 *
 * Active rules (simplest correct definition):
 * 1. Exact match: currentRouteName === item.to.name
 * 2. Prefix match for nested routes: currentRouteName starts with
 *    item.to.name + '-'  (e.g. item "organisation" is active on
 *    "organisation-settings"). The dash boundary prevents "org" from
 *    spuriously matching "organisation-settings".
 *
 * Only `to` values that are a plain object with a string `name` property are
 * compared — string/array `to` values always return false (router-push
 * style not used in v1 nav).
 */
export function isNavItemActive(
  item: V2NavItem,
  currentRouteName: string | symbol | null | undefined,
): boolean {
  if (typeof currentRouteName !== 'string')
    return false

  const to = item.to

  if (typeof to !== 'object' || to === null || Array.isArray(to))
    return false

  const itemName = (to as { name?: unknown }).name

  if (typeof itemName !== 'string')
    return false

  return currentRouteName === itemName
    || currentRouteName.startsWith(`${itemName}-`)
}