import { cache } from "react";
import { auth } from "@/auth";
import { prisma } from "@/lib/db/prisma";
import { isSuperAdmin } from "@/lib/auth/permissions";
import { getPrimaryBusiness } from "@/lib/business/get-primary-business";

/**
 * Resolves "which business is the signed-in user acting on behalf of" for
 * pages/actions that only need the business id/name/timezone — not full
 * staff identity (see getActingStaff for that, which stays the right
 * choice for anything that needs a real StaffProfile id, e.g. loyalty
 * stamp authorship or appointment reassignment).
 *
 * A regular staff member/owner resolves via their StaffProfile, same as
 * getActingStaff. A Super Administrator (see scripts/ensure-super-admin.ts)
 * deliberately has no StaffProfile at all — that's what keeps them out of
 * the Team list/barber picker/appointment FKs by construction rather than
 * a filter — so they resolve straight to the app's one business instead
 * (v1 is single-business, same assumption getPrimaryBusiness() already
 * makes everywhere else). Returns null only for a signed-in user who is
 * neither staff nor a super admin.
 */
export const getActingBusinessContext = cache(async () => {
  const session = await auth();
  if (!session?.user?.id) return null;

  const staffProfile = await prisma.staffProfile.findUnique({
    where: { userId: session.user.id },
    select: { id: true, businessId: true, business: { select: { name: true, timezone: true } } },
  });
  if (staffProfile) {
    return {
      userId: session.user.id,
      staffId: staffProfile.id,
      businessId: staffProfile.businessId,
      businessName: staffProfile.business.name,
      businessTimezone: staffProfile.business.timezone,
    };
  }

  if (!(await isSuperAdmin(session.user.id))) return null;

  const business = await getPrimaryBusiness();
  return {
    userId: session.user.id,
    // A Super Administrator has no StaffProfile by design (see isSuperAdmin) —
    // null here is what lets callers tell "acting as real staff" apart from
    // "acting as a Super Administrator with no personal staff identity",
    // e.g. to withhold note authorship (see CustomerNotes' actingStaffId).
    staffId: null,
    businessId: business.id,
    businessName: business.name,
    businessTimezone: business.timezone,
  };
});

export type ActingBusinessContext = NonNullable<Awaited<ReturnType<typeof getActingBusinessContext>>>;