"use server";

import { redirect } from "next/navigation";
import { z } from "zod";
import { db } from "@/lib/db";
import { auth } from "@/lib/auth";
import { getCart, cartTotal, setCartItems } from "@/lib/cart";

const CheckoutSchema = z.object({
  name: z.string().min(2, "Zadej jméno a příjmení"),
  email: z.string().email("Neplatný e-mail"),
  phone: z.string().optional(),
  street: z.string().min(3, "Zadej ulici a číslo popisné"),
  city: z.string().min(2, "Zadej město"),
  zip: z.string().regex(/^\d{3}\s?\d{2}$/, "Neplatné PSČ (např. 110 00)"),
  country: z.string().default("CZ"),
  note: z.string().optional(),
});

export type CheckoutFormState = {
  error?: string;
  fieldErrors?: Record<string, string[]>;
};

export async function createOrder(
  _prev: CheckoutFormState,
  formData: FormData
): Promise<CheckoutFormState> {
  const parsed = CheckoutSchema.safeParse({
    name: formData.get("name"),
    email: formData.get("email"),
    phone: formData.get("phone"),
    street: formData.get("street"),
    city: formData.get("city"),
    zip: formData.get("zip"),
    country: formData.get("country") || "CZ",
    note: formData.get("note"),
  });

  if (!parsed.success) {
    return { fieldErrors: parsed.error.flatten().fieldErrors };
  }

  const items = await getCart();
  if (items.length === 0) {
    return { error: "Košík je prázdný." };
  }

  const session = await auth();
  const total = cartTotal(items);

  const order = await db.order.create({
    data: {
      userId: session?.user?.id ?? null,
      guestEmail: session ? null : parsed.data.email,
      status: "PENDING",
      totalAmount: total,
      shippingName: parsed.data.name,
      shippingEmail: parsed.data.email,
      shippingPhone: parsed.data.phone || null,
      shippingStreet: parsed.data.street,
      shippingCity: parsed.data.city,
      shippingZip: parsed.data.zip.replace(/\s/g, ""),
      shippingCountry: parsed.data.country,
      items: {
        create: items.map((item) => ({
          productId: item.variant.product.id,
          variantId: item.variantId,
          quantity: item.quantity,
          unitPrice: item.variant.price,
        })),
      },
    },
  });

  // Vyprázdnit košík
  await setCartItems([]);

  redirect(`/objednavka/${order.id}`);
}

// ── Admin: změna stavu objednávky ─────────────────────────────────────────

export async function updateOrderStatus(id: string, status: string) {
  await db.order.update({
    where: { id },
    data: { status: status as never },
  });
}