import {
  LayoutDashboard,
  ClipboardList,
  FileInput,
  Users,
  Building2,
  UsersRound,
  FileText,
  FolderOpen,
  Settings,
  type LucideIcon,
} from "lucide-react";
import type { ModuleKey } from "@/lib/modules";
import type { Permission } from "@/server/rbac";

/**
 * Sidebar-Navigation des Backoffice (src/app/(app)/layout.tsx).
 *
 * Ein Eintrag ist sichtbar, wenn
 *   - sein Modul (falls gesetzt) für den Mandanten aktiv ist UND
 *   - die Session mindestens EINE der `permissions` hat (leer = immer).
 * Das ist reiner Komfort — Seiten und Actions prüfen Modul + Rechte serverseitig selbst.
 *
 * Neue Backoffice-Seite ⇒ hier eintragen; `label` ist ein Schlüssel in messages nav.*.
 * Mobile-Einträge (/m, /m/emergency) gehören NICHT hierher (eigene Mobile-Navigation).
 */
export interface NavItem {
  href: string;
  label: string;
  icon: LucideIcon;
  module?: ModuleKey;
  permissions?: readonly Permission[];
  section: "main" | "admin";
}

export const NAV_ITEMS: readonly NavItem[] = [
  { href: "/dashboard", label: "dashboard", icon: LayoutDashboard, section: "main" },
  {
    href: "/work-orders",
    label: "workOrders",
    icon: ClipboardList,
    module: "work_orders",
    permissions: ["work_order:read_all", "work_order:read_team"],
    section: "main",
  },
  { href: "/imports", label: "imports", icon: FileInput, module: "imports", permissions: ["import:write"], section: "main" },
  { href: "/customers", label: "customers", icon: Users, module: "customers", permissions: ["customer:read"], section: "main" },
  { href: "/sites", label: "sites", icon: Building2, module: "sites", permissions: ["site:read"], section: "main" },
  { href: "/teams", label: "teams", icon: UsersRound, module: "teams", permissions: ["team:read"], section: "main" },
  { href: "/reports", label: "reports", icon: FileText, module: "reports", permissions: ["report:read"], section: "main" },
  { href: "/documents", label: "documents", icon: FolderOpen, module: "documents", permissions: ["document:read"], section: "main" },
  { href: "/settings", label: "settings", icon: Settings, permissions: ["tenant:manage"], section: "admin" },
];

/** Filtert die Navigation nach aktiven Modulen und Rechten der Session. */
export function visibleNavItems(
  items: readonly NavItem[],
  opts: { disabledModules: ReadonlySet<string>; permissions: readonly string[] },
): NavItem[] {
  return items.filter(
    (item) =>
      (!item.module || !opts.disabledModules.has(item.module)) &&
      (!item.permissions?.length || item.permissions.some((p) => opts.permissions.includes(p))),
  );
}